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https://en.wikipedia.org/wiki/Self-shrinking%20generator
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A self-shrinking generator is a pseudorandom generator that is based on the shrinking generator concept. Variants of the self-shrinking generator based on a linear-feedback shift register (LFSR) are studied for use in cryptography.
Algorithm
In difference to the shrinking generator, which uses a second feedback shift register to control the output of the first, the self-shrinking generator uses alternating output bits of a single register to control its final output. The procedure for clocking this kind of generator is as follows:
Clock the LFSR twice to obtain a pair of bits as LFSR output.
If the pair is 10 output a zero.
If the pair is 11 output a one.
Otherwise, output nothing.
Return to step one.
Example
This example will use the connection polynomial x8 + x4 + x3 + x2 + 1,
and an initial register fill of 1 0 1 1 0 1 1 0.
Below table lists, for each iteration of the LFSR, its intermediate output before self-shrinking, as well as the final generator output. The tap positions defined by the connection polynomial are marked with blue headings. The state of the zeroth iteration represents the initial input.
At the end of four iterations, the following sequence of intermediate bits is produced: 0110.
The first pair of bits, 01, is discarded since it does not match either 10 or 11.
The second pair of bits, 10, matches the second step of the algorithm so a zero is output.
More bits are created by continuing to clock the LFSR and shrinking its output as described above.
Cryptanalysis
In their paper, Meier and Steffelbach prove that a LFSR-based self-shrinking generator with a connection polynomial of length L results in an output sequence period of at least 2L/2, and a linear complexity of at least 2L/2-1.
Furthermore, they show that any self-shrinking generator can be represented as a shrinking-generator. The inverse is also true:
Any shrinking generator can be implemented as a self-shrinking generator, although the resultant generator may not be of
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https://en.wikipedia.org/wiki/Missing%20dollar%20riddle
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The missing dollar riddle is a famous riddle that involves an informal fallacy. It dates to at least the 1930s, although similar puzzles are much older.
Statement
Although the wording and specifics can vary, the puzzle runs along these lines:
Three guests check into a hotel room. The manager says the bill is $30, so each guest pays $10. Later the manager realizes the bill should only have been $25. To rectify this, he gives the bellhop $5 as five one-dollar bills to return to the guests.
On the way to the guests' room to refund the money, the bellhop realizes that he cannot equally divide the five one-dollar bills among the three guests. As the guests are not aware of the total of the revised bill, the bellhop decides to just give each guest $1 back and keep $2 as a tip for himself, and proceeds to do so.
As each guest got $1 back, each guest only paid $9, bringing the total paid to $27. The bellhop kept $2, which when added to the $27, comes to $29. So if the guests originally handed over $30, what happened to the remaining $1?
There seems to be a discrepancy, as there cannot be two answers ($29 and $30) to the math problem. On the one hand it is true that the $25 in the register, the $3 returned to the guests, and the $2 kept by the bellhop add up to $30, but on the other hand, the $27 paid by the guests and the $2 kept by the bellhop add up to only $29.
Solution
The misdirection in this riddle is in the second half of the description, where unrelated amounts are added together and the person to whom the riddle is posed assumes those amounts should add up to 30, and is then surprised when they do not — there is, in fact, no reason why the (10 − 1) × 3 + 2 = 29 sum should add up to 30.
The exact sum mentioned in the riddle is computed as:
SUM = $9 (payment by Guest 1) +
$9 (payment by Guest 2) +
$9 (payment by Guest 3) +
$2 (money in bellhop's pocket)
The trick here is to realize that this is not a sum of t
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https://en.wikipedia.org/wiki/The%20Eidolon
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The Eidolon was one of two games that were part of Lucasfilm Games' second wave in December 1985. The other was Koronis Rift. Both took advantage of the fractal technology developed for Rescue on Fractalus!, further enhancing it. In The Eidolon, Rescue'''s fractal mountains were turned upside down and became the inside of a cave.
In addition to common cassette formats, the Atari and Commodore 64 versions were supplied on a floppy disk. One side had the Atari version, and the other had the Commodore 64 version. The Atari version required an XL/XE with 64kB or more memory.
Plot
The player discovers the Eidolon, a strange 19th-century vehicle, in an abandoned laboratory. As the player investigates this device, he is accidentally transported to another dimension and is trapped in a vast, maze-like cave. The creatures in this cave, sensing the energy emanating from the Eidolon, are woken from a long slumber, and the player soon finds that his only chance of survival lies in this mysterious vehicle and its powerful energy weapon.
Gameplay
The objective of The Eidolon is to successfully navigate through all of the game's levels, defeating the dragon guardian at the end of each level. The player navigates through each maze and collects energy orbs, which come in four different colors (red, yellow, green and blue). Along the way, various enemies wake up and attack the Eidolon, attempting to absorb its energy. Some enemies also fire orbs at the Eidolon, of which all but the red orbs can be absorbed by pressing the space bar at the right time to replenish the Eidolon's limited energy.
Green orbs also have the power to transform other enemies into different kinds of enemies. Blue orbs can freeze enemies temporarily, giving the player a momentary advantage in a fight.
Each level contains three diamonds, each guarded by an enemy of a specific color. After defeating each of these enemies and collecting the diamonds, the player can proceed to the dragon that guards the exit.
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https://en.wikipedia.org/wiki/Koronis%20Rift
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Koronis Rift is a 1985 computer game from Lucasfilm Games. It was produced and designed by Noah Falstein. Originally developed for the Atari 8-bit family and the Commodore 64, Koronis Rift was ported to the Amstrad CPC, Apple II, MSX2, Tandy Color Computer 3, and ZX Spectrum.
The Atari and C64 version shipped on a flippy disk, with one version of the game on each side. A cassette version was also released for the Commodore 64. The Atari version required computers with the GTIA chip installed in order to display properly.
Koronis Rift was one of two games in Lucasfilm Games' second wave (December 1985). The other was The Eidolon. Both enhanced the fractal technology developed for Rescue on Fractalus!. In Koronis Rift, the Atari 8-bit family's additional colors (over those of the Commodore 64) allowed the programmers to gradually fade in the background rather than it suddenly popping in as in Rescue, an early example of depth cueing in a computer game.
Gameplay
The player controls a surface rover vehicle to enter several "rifts" on an alien planet which are effectively fractal mazes. A lost civilisation known as the Ancients has left strange machinery, so-called "hulks", within these rifts which are guarded by armed flying saucers of different design and color. Depending on their respective color, shields and gunshots of both the rover and the saucers are of varying effectiveness against each other; part of the game is figuring out which shield and weapon modules work best where.
By means of a drone robot, the rover can retrieve modules with various functions (which are not immediately obvious) from nearby hulks. It can only be deployed when all attacking Guardian Saucers have been destroyed. The modules can then be installed in the rover, analyzed aboard the player's space ship, or sold; the rover can carry up to six different modules at a time which can be activated and de-activated as the player sees fit. A large variety of modules is available: Different we
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https://en.wikipedia.org/wiki/Pregap
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The pregap on a Red Book audio CD is the portion of the audio track that precedes "index 01" for a given track in the table of contents (TOC). The pregap ("index 00") is typically two seconds long and usually, but not always, contains silence. Popular uses for having the pregap contain audio are live CDs, track interludes, and hidden songs in the pregap of the first track (detailed below).
Unconventional uses of the pregap
Computer data in pregap
The track 01 pregap was used to hide computer data, allowing computers to detect a data track whereas conventional CD players would continue to see the CD as an audio CD.
This method was made obsolete in mid 1996 when an update to Windows 95 in driver SCSI1HLP.VXD made the pregap track inaccessible. It is unclear whether this change in Microsoft Windows' behavior was intentional: for instance, it may have been intended to steer developers away from the pregap method and encourage what became the Blue Book specification "CD Extra" format.
Hidden audio tracks
On certain CDs, such as Light Years by Kylie Minogue, HoboSapiens by John Cale, or Factory Showroom by They Might Be Giants, the pregap before track 1 contains a hidden track. The track is truly hidden in the sense that most conventional standalone players and software CD players will not see it.
Such hidden tracks can be played by playing the first song and "rewinding" (more accurately, seeking in reverse) until the actual start of the whole CD audio track.
Not all CD drives can properly extract such hidden tracks. Some drives will report errors when reading these tracks, and some will seem to extract them properly, but the extracted file will contain only silence.
Other CDs contain additional audio information in the pre-gap area of other tracks, resulting in the audio only being heard on a conventional CD player if the CD is allowed to "play through," but not if you jump to the next track.
Some CDs also contain phantom tracks consisting of only index 0 data,
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https://en.wikipedia.org/wiki/223%20%28number%29
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223 (two hundred [and] twenty-three) is the natural number following 222 and preceding 224.
In mathematics
223 is a prime number. Among the 720 permutations of the numbers from 1 to 6, exactly 223 of them have the property that at least one of the numbers is fixed in place by the permutation and the numbers less than it and greater than it are separately permuted among themselves.
In connection with Waring's problem, 223 requires the maximum number of terms (37 terms) when expressed as a sum of positive fifth powers, and is the only number that requires that many terms.
In other fields
.223 (disambiguation), the caliber of several firearm cartridges
The years 223 and 223 BC
The number of synodic months of a Saros
References
Integers
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https://en.wikipedia.org/wiki/227%20%28number%29
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227 (two hundred [and] twenty-seven) is the natural number between 226 and 228. It is also a prime number.
In mathematics
227 is a twin prime and the start of a prime triplet (with 229 and 233). It is a safe prime, as dividing it by two and rounding down produces the Sophie Germain prime 113. It is also a regular prime, a Pillai prime, a Stern prime, and a Ramanujan prime.
227 and 229 form the first twin prime pair for which neither is a cluster prime.
The 227th harmonic number is the first to exceed six. There are 227 different connected graphs with eight edges, and 227 independent sets in a 3 × 4 grid graph.
References
Integers
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https://en.wikipedia.org/wiki/Grand%20Challenges
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Grand Challenges are difficult but important problems set by various institutions or professions to encourage solutions or advocate for the application of government or philanthropic funds especially in the most highly developed economies and
Grand challenges are more than ordinary research questions or priorities, they are end results or outcomes that are global in scale; very difficult to accomplish, yet offer hope of being ultimately tractable; demand an extensive number of research projects across many technical and non-technical disciplines and accompanied by well-defined metrics. Lastly, Grand challenges "require coordinated, collaborative, and collective efforts" and must capture "the popular imagination, and thus political support."
In engineering
Grand Challenges: A Strategic Plan for Bridge Engineering, initiative sponsored by the Highway Subcommittee on Bridges and Structures (HSCOBS) of the American Association of State Highway and Transportation Officials (AASHTO) started in 2000.
Grand Challenges for Engineering, initiative sponsored by the National Academy of Engineering (NAE) for engineering problems in the next century.
Global Grand Challenges, summit meetings sponsored by The National Academy of Engineering of the United States, The Royal Academy of Engineering of the United Kingdom, and the Chinese Academy of Engineering.
ASCE Grand Challenge for Civil Engineering, initiative by the American Society of Civil Engineering's (ASCE) to enhance significantly the performance and life-cycle value of infrastructure by 2025.
Grand Challenges for Disaster Reduction, initiative sponsored by the National Science and Technology Council, Committee on Environment and Natural Resources.
In government and military
DARPA Grand Challenge, initiative to develop technologies needed to create fully autonomous ground vehicles, capable of completing a substantial off-road course within a limited time.
DARPA Urban Challenge, part of DARPA's Grand Chall
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https://en.wikipedia.org/wiki/Organic%20peroxides
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In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily breaks, producing free radicals of the form (the dot represents an unpaired electron). Thus, organic peroxides are useful as initiators for some types of polymerization, such as the acrylic, unsaturated polyester, and vinyl ester resins used in glass-reinforced plastics. MEKP and benzoyl peroxide are commonly used for this purpose. However, the same property also means that organic peroxides can explosively combust. Organic peroxides, like their inorganic counterparts, are often powerful bleaching agents.
Types of organic peroxides
Organic peroxides are classified (i) by the presence or absence of a hydroxyl (-OH) terminus and (ii) by the presence of alkyl vs acyl substituents. One gap in the classes of organic peroxides is diphenyl peroxide. Quantum chemical calculations predict that it undergoes a nearly barrierless reaction akin to the benzidine rearrangement.
Properties
The O−O bond length in peroxides is about 1.45 Å, and the R−O−O angles (R = H, C) are about 110° (water-like). Characteristically, the C−O−O−R (R = H, C) dihedral angles are about 120°. The O−O bond is relatively weak, with a bond dissociation energy of , less than half the strengths of C−C, C−H, and C−O bonds.
Biology
Peroxides play important roles in biology. Many aspects of biodegradation or aging are attributed to the formation and decay of peroxides formed from oxygen in air. Countering these effects is an array of biological and artificial antioxidants.
Hundreds of peroxides and hydroperoxides are known, being derived from fatty acids, steroids, and terpenes. Fatty acids form a number of 1,2-dioxenes. The biosynthesis prostaglandins proceeds via an endoperoxide, a class of bicyclic peroxides.
In fireflies, oxidation of luciferins, which is cata
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https://en.wikipedia.org/wiki/Basilic%20vein
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The basilic vein is a large superficial vein of the upper limb that helps drain parts of the hand and forearm. It originates on the medial (ulnar) side of the dorsal venous network of the hand and travels up the base of the forearm, where its course is generally visible through the skin as it travels in the subcutaneous fat and fascia lying superficial to the muscles. The basilic vein terminates by uniting with the brachial veins to form the axillary vein.
Anatomy
Course
As it ascends the medial side of the biceps in the arm proper (between the elbow and shoulder), the basilic vein normally perforates the brachial fascia (deep fascia) superior to the medial epicondyle, or even as high as mid-arm.
Tributaries and anastomoses
Near the region anterior to the cubital fossa (in the bend of the elbow joint), the basilic vein usually communicates with the cephalic vein (the other large superficial vein of the upper extremity) via the median cubital vein. The layout of superficial veins in the forearm is highly variable from person to person, and there is a profuse network of unnamed superficial veins that the basilic vein communicates with.
Around the inferior border of the teres major muscle and just proximal to the basilic vein's termination, the anterior and posterior circumflex humeral veins drain into it.
Clinical significance
Venipuncture
Along with other superficial veins in the forearm, the basilic vein is an acceptable site for venipuncture. Nevertheless, IV nurses sometimes refer to the basilic vein as the "virgin vein", since with the arm typically supinated during phlebotomy the basilic vein below the elbow becomes awkward to access, and is therefore infrequently used.
Venous grafts
Vascular surgeons sometimes utilize the basilic vein to create an AV (arteriovenous) fistula or AV graft for hemodialysis access in patients with kidney failure.
Additional images
See also
Cephalic vein
Median cubital vein
External links
Illustration
References
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https://en.wikipedia.org/wiki/Coolgardie%20safe
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The Coolgardie safe is a low-tech food storage unit, using evaporative cooling to prolong the life of whatever edibles are kept in it. It applies the basic principle of heat transfer which occurs during evaporation of water (see latent heat and heat of evaporation). It was named after the place where it was invented – the small mining town of Coolgardie, Western Australia, near Kalgoorlie-Boulder.
History
Coolgardie was the site of a gold rush in the early 1890s, before the Kalgoorlie-Boulder gold rush.
For the prospectors who had rushed here to find their fortune, one challenge was to extend the life of their perishable foods – hence the invention of the Coolgardie safe.
The safe was invented in the late 1890s by Arthur Patrick McCormick, who used the same principle as explorers and travelers in the Outback used to cool their canvas water bags: when the canvas bag is wet the fibers expand and it holds water. Some water seeps out and evaporates. It is most effective when air continually moves past it, such as when in a moving vehicle or when exposed to a breeze.
This technology is commonly thought to have been adopted by explorer and scientist Thomas Mitchell, who had observed the way some Indigenous Australians used kangaroo skins to carry water.
Principles of operation
The Coolgardie safe was made of wire mesh, hessian, a wooden frame and had a hot dip galvanised iron tray on top. The galvanised iron tray was filled with water. The hessian bag was hung over the side with one of the ends in the tray to soak up the water.
Gradually the hessian bag, acting as a wick, would draw water from the tray by the process of capillary action. When a breeze came it would pass through the wet bag and evaporate the water. This would cool the air inside the safe, and in turn cool the food stored in the safe. This cooling is due to the water in the hessian needing energy to change state and evaporate. This energy is taken from the interior of the safe (metal mesh), thus m
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https://en.wikipedia.org/wiki/Mueller%20calculus
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Mueller calculus is a matrix method for manipulating Stokes vectors, which represent the polarization of light. It was developed in 1943 by Hans Mueller. In this technique, the effect of a particular optical element is represented by a Mueller matrix—a 4×4 matrix that is an overlapping generalization of the Jones matrix.
Introduction
Disregarding coherent wave superposition, any fully polarized, partially polarized, or unpolarized state of light can be represented by a Stokes vector ; and any optical element can be represented by a Mueller matrix (M).
If a beam of light is initially in the state and then passes through an optical element M and comes out in a state , then it is written
If a beam of light passes through optical element M1 followed by M2 then M3 it is written
given that matrix multiplication is associative it can be written
Matrix multiplication is not commutative, so in general
Mueller vs. Jones calculi
With disregard for coherence, light which is unpolarized or partially polarized must be treated using the Mueller calculus, while fully polarized light can be treated with either the Mueller calculus or the simpler Jones calculus. Many problems involving coherent light (such as from a laser) must be treated with Jones calculus, however, because it works directly with the electric field of the light rather than with its intensity or power, and thereby retains information about the phase of the waves.
More specifically, the following can be said about Mueller matrices and Jones matrices:
Stokes vectors and Mueller matrices operate on intensities and their differences, i.e. incoherent superpositions of light; they are not adequate to describe either interference or diffraction effects.
(...)
Any Jones matrix [J] can be transformed into the corresponding Mueller–Jones matrix, M, using the following relation:
,
where * indicates the complex conjugate [sic], [A is:]
and ⊗ is the tensor (Kronecker) product.
(...)
While the Jones matrix has eight i
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https://en.wikipedia.org/wiki/Closure%20with%20a%20twist
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Closure with a twist is a property of subsets of an algebraic structure. A subset of an algebraic structure is said to exhibit closure with a twist if for every two elements
there exists an automorphism of and an element such that
where "" is notation for an operation on preserved by .
Two examples of algebraic structures which exhibit closure with a twist are the cwatset and the generalized cwatset, or GC-set.
Cwatset
In mathematics, a cwatset is a set of bitstrings, all of the same length, which is closed with a twist.
If each string in a cwatset, C, say, is of length n, then C will be a subset of . Thus, two strings in C are added by adding the bits in the strings modulo 2 (that is, addition without carry, or exclusive disjunction). The symmetric group on n letters, , acts on by bit permutation:
where is an element of and p is an element of . Closure with a twist now means that for each element c in C, there exists some permutation such that, when you add c to an arbitrary element e in the cwatset and then apply the permutation, the result will also be an element of C. That is, denoting addition without carry by , C will be a cwatset if and only if
This condition can also be written as
Examples
All subgroups of — that is, nonempty subsets of which are closed under addition-without-carry — are trivially cwatsets, since we can choose each permutation pc to be the identity permutation.
An example of a cwatset which is not a group is
F = {000,110,101}.
To demonstrate that F is a cwatset, observe that
F + 000 = F.
F + 110 = {110,000,011}, which is F with the first two bits of each string transposed.
F + 101 = {101,011,000}, which is the same as F after exchanging the first and third bits in each string.
A matrix representation of a cwatset is formed by writing its words as the rows of a 0-1 matrix. For instance a matrix representation of F is given by
To see that F is a cwatset using this notation, note that
where and denote permut
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https://en.wikipedia.org/wiki/Differential-linear%20attack
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Introduced by Martin Hellman and Susan K. Langford in 1994, the differential-linear attack is a mix of both linear cryptanalysis and differential cryptanalysis.
The attack utilises a differential characteristic over part of the cipher with a probability of 1 (for a few rounds—this probability would be much lower for the whole cipher). The rounds immediately following the differential characteristic have a linear approximation defined, and we expect that for each chosen plaintext pair, the probability of the linear approximation holding for one chosen plaintext but not the other will be lower for the correct key. Hellman and Langford have shown that this attack can recover 10 key bits of an 8-round DES with only 512 chosen plaintexts and an 80% chance of success.
The attack was generalised by Eli Biham et al. to use differential characteristics with probability less than 1. Besides DES, it has been applied to FEAL, IDEA, Serpent, Camellia, and even the stream cipher Phelix.
References
Cryptographic attacks
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https://en.wikipedia.org/wiki/Anti-diagonal%20matrix
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In mathematics, an anti-diagonal matrix is a square matrix where all the entries are zero except those on the diagonal going from the lower left corner to the upper right corner (↗), known as the anti-diagonal (sometimes Harrison diagonal, secondary diagonal, trailing diagonal, minor diagonal, off diagonal or bad diagonal).
Formal definition
An n-by-n matrix A is an anti-diagonal matrix if the (i, j) element is zero
Example
An example of an anti-diagonal matrix is
Properties
All anti-diagonal matrices are also persymmetric.
The product of two anti-diagonal matrices is a diagonal matrix. Furthermore, the product of an anti-diagonal matrix with a diagonal matrix is anti-diagonal, as is the product of a diagonal matrix with an anti-diagonal matrix.
An anti-diagonal matrix is invertible if and only if the entries on the diagonal from the lower left corner to the upper right corner are nonzero. The inverse of any invertible anti-diagonal matrix is also anti-diagonal, as can be seen from the paragraph above. The determinant of an anti-diagonal matrix has absolute value given by the product of the entries on the diagonal from the lower left corner to the upper right corner. However, the sign of this determinant will vary because the one nonzero signed elementary product from an anti-diagonal matrix will have a different sign depending on whether the permutation related to it is odd or even:
More precisely, the sign of the elementary product needed to calculate the determinant of an anti-diagonal matrix is related to whether the corresponding triangular number is even or odd. This is because the number of inversions in the permutation for the only nonzero signed elementary product of any n × n anti-diagonal matrix is always equal to the nth such number.
See also
Main diagonal, all off-diagonal elements are zero in a diagonal matrix.
Exchange matrix, an anti-diagonal matrix with 1s along the counter-diagonal.
External links
Matrix calculator
Sparse matrices
Ma
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https://en.wikipedia.org/wiki/Console%20%28computer%20games%29
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A console is a command line interface where the personal computer game's settings and variables can be edited while the game is running. Consoles also usually display a log of warnings, errors, and other messages produced during the program's execution. Typically it can be toggled on or off and appears over the normal game view.
The console is normally accessed by pressing the backtick key ` (frequently also called the ~ key; normally located below the ESC key) on QWERTY keyboards or the ² on AZERTY keyboards, and is usually hidden by default. In most cases it cannot be accessed unless enabled by either specifying a command-line argument when launching the game or by changing one of the game's configuration files.
History
A classic console is a box that scrolls down from the top of the screen. This style was made popular with Quake (1996). There are other forms of console:
Quake III Arena has one or two consoles, depending on the platform the game was released for. The first is the internal console, which exists on all platforms. The second is an external console, created via the Windows API. The console printing function directs to both, likewise, both consoles can also have text input to them. The external console is used for dedicated servers and to log startup of the engine. Finally, the external console is also used to show errors and display debugging output should the game crash.
Dark Engine's console shows output up to 4 lines in length and is accessed by pressing 3 particular keys at the same time.
Lithtech's console has no output and is used mainly for entering cheat codes.
ARK: Survival Evolved is an open world action and adventure survival video game is by Studio Wildcard. A lot of ARK commands will require the ‘Enable Cheats‘ command to be used before going further, as well as the Enable Cheats for Player command. It is an absolute must to use this before using to any other command.
A single-line variant can be seen in games from The Sims serie
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https://en.wikipedia.org/wiki/Trip-a-Tron
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Trip-a-Tron is a light synthesizer written by Jeff Minter and published through his Llamasoft company in 1988. It was originally written for the Atari ST and later ported to the Amiga in 1990 by Andy Fowler.
Description
Trip-A-Tron was released as shareware, but also came in a commercial package with a 3-ring-bound manual and 2 game disks. The trial version contained no limitations, but registration was necessary to obtain the manual, which in turn was necessary to learn the script language ("KML" - supposedly "Keyboard Macro Language" and only coincidentally the phonetic equivalent of "camel") which drove the system.
The software has a usable but quirky user interface, filled with in-jokes and references to Llamasoft mascots. For example, the button to exit from the MIDI editor is labelled "naff off", while the button to exit the file display is labelled with a sheep saying "Baa!"; the waveform editor colour cycles the words "Dead cool" above the waveform display, and the event sequencer displays an icon of a camel smoking a cigarette; and the image manipulation tool has a series of icons used to indicate how long the current operation is going to take: "Make the tea", "Have a fag", "Go to bed", "Go to sleep", "Go on holiday", "Go to Peru for six months", and "RIP"; and the scripting language command to set the length of drawn lines is "LLAMA". (The manual states: "I could have called the command LINELENGTH I suppose, but I like llamas so what the heck".)
The manual is also written in a similar light, conversational style, but has been praised for nonetheless achieving a high degree of technical clarity.
In spite of this the software is extremely usable and was recommended as one of the best light synthesizers available at the time.
See also
Psychedelia (light synthesizer)
Virtual Light Machine
Neon (light synthesizer)
References
External links
1988 software
Atari ST software
Amiga software
Music visualization software
Llamasoft software
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https://en.wikipedia.org/wiki/Steinhart%E2%80%93Hart%20equation
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The Steinhart–Hart equation is a model of the resistance of a semiconductor at different temperatures. The equation is
where
is the temperature (in kelvins),
is the resistance at (in ohms),
, , and are the Steinhart–Hart coefficients, which vary depending on the type and model of thermistor and the temperature range of interest.
Uses of the equation
The equation is often used to derive a precise temperature of a thermistor, since it provides a closer approximation to actual temperature than simpler equations, and is useful over the entire working temperature range of the sensor. Steinhart–Hart coefficients are usually published by thermistor manufacturers.
Where Steinhart–Hart coefficients are not available, they can be derived. Three accurate measures of resistance are made at precise temperatures, then the coefficients are derived by solving three simultaneous equations.
Inverse of the equation
To find the resistance of a semiconductor at a given temperature, the inverse of the Steinhart–Hart equation must be used. See the Application Note, "A, B, C Coefficients for Steinhart–Hart Equation".
where
Steinhart–Hart coefficients
To find the coefficients of Steinhart–Hart, we need to know at-least three operating points. For this, we use three values of resistance data for three known temperatures.
With , and values of resistance at the temperatures , and , one can express , and (all calculations):
Developers of the equation
The equation is named after John S. Steinhart and Stanley R. Hart who first published the relationship in 1968. Professor Steinhart (1929–2003), a fellow of the American Geophysical Union and of the American Association for the Advancement of Science, was a member of the faculty of University of Wisconsin–Madison from 1969 to 1991. Dr. Hart, a Senior Scientist at Woods Hole Oceanographic Institution since 1989 and fellow of the Geological Society of America, the American Geophysical Union, the Geochemical Society and the
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https://en.wikipedia.org/wiki/Mickey%20Mouse%20Clubhouse
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Mickey Mouse Clubhouse is an American interactive animated television series which was the first Mickey Mouse and computer-animated program for preschoolers. Produced by Disney Television Animation, the series was created by Disney veteran Bobs Gannaway. The series originally aired 125 episodes from May 5, 2006, to November 6, 2016, on the Disney Channel. It received generally positive reviews from critics.
On August 18, 2023, a revival was revealed to be in production, and is set to be released in 2025.
Premise
Mickey, Minnie, Donald, Daisy, Goofy, and Pluto interact with the viewer to stimulate problem solving during a self contained story.
Once the problem of the episode has been explained, Mickey invites the viewers to join him at the Mousekedoer, a giant Mickey-head-shaped computer whose main function is to distribute the day's Mouseketools, a collection of tools needed to solve the day's problem, to Mickey.
One of them is a "Mystery Mouseketool" represented by a Question Mark, in which, when the words "Mystery Mouseketool" are said, the question mark changes into the Mouseketool the viewer gets to use. Another one is a "Mouseke-Think-About-It Tool" represented by a silhouette of Mickey's head with rotating gears, in which characters must think of what to use before telling the Tool "Mouseke-Think-About-It-Tool, we pick the (object)". Once the tools have been shown to Mickey on the Mousekedoer screen, they are quickly downloaded to Toodles, a small, Mickey-head-shaped flying extension of the Mousekedoer. By calling "Oh, Toodles!" Mickey summons him to pop up from where he is hiding and fly up to the screen so the viewer can pick which tool Mickey needs for the current situation. Rhymes are used throughout the show. For example, in "Mickey's Silly Problem", when the "Silly switch" turned on, Mickey for some reason, spoke in rhymes for half of the episode.
The show features two original songs performed by American alternative rock band They Might Be Giants,
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https://en.wikipedia.org/wiki/Viscosity%20solution
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In mathematics, the viscosity solution concept was introduced in the early 1980s by Pierre-Louis Lions and Michael G. Crandall as a generalization of the classical concept of what is meant by a 'solution' to a partial differential equation (PDE). It has been found that the viscosity solution is the natural solution concept to use in many applications of PDE's, including for example first order equations arising in dynamic programming (the Hamilton–Jacobi–Bellman equation), differential games (the Hamilton–Jacobi–Isaacs equation) or front evolution problems, as well as second-order equations such as the ones arising in stochastic optimal control or stochastic differential games.
The classical concept was that a PDE
over a domain has a solution if we can find a function u(x) continuous and differentiable over the entire domain such that , , , satisfy the above equation at every point.
If a scalar equation is degenerate elliptic (defined below), one can define a type of weak solution called viscosity solution.
Under the viscosity solution concept, u does not need to be everywhere differentiable. There may be points where either or does not exist and yet u satisfies the equation in an appropriate generalized sense. The definition allows only for certain kind of singularities, so that existence, uniqueness, and stability under uniform limits, hold for a large class of equations.
Definition
There are several equivalent ways to phrase the definition of viscosity solutions. See for example the section II.4 of Fleming and Soner's book or the definition using semi-jets in the Users Guide.
Degenerate elliptic An equation in a domain is defined to be degenerate elliptic if for any two symmetric matrices and such that is positive definite, and any values of , and , we have the inequality . For example, (where denotes the Laplacian) is degenerate elliptic since in this case, , and the trace of is the sum of its eigenvalues. Any real first- order equation is
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https://en.wikipedia.org/wiki/PCB%20NC%20formats
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PCB NC drill files convey PCB drilling and routing information. The NC formats were originally designed by CNC drill and route machine vendors as proprietary input formats for their equipment, and are known under their company name: Excellon, Hitachi, Sieb & Meyer, Posalux, etc. These formats are similar as they are based on RS-274-C and related to G-code. In 1985 IPC published a generic standard NC format, IPC-NC-349. Later XNC was designed, a simple strict subset of IPC-NC-349, designed not for driving machines but for exchanging drill information between CAD and CAM. They are collectively referred to as (PCB) NC files.
The NC files are primarily used to drive CNC machines, and they are adequate for that task.
They are also used to exchange design information between CAD and CAM, for which they are not adequate: essential information such as plating and drill span is missing. Furthermore, the NC output in CAD systems is often poorly implemented, resulting in poor registration between drill holes and copper layers and other problems. To exchange data between CAD and CAM it is more preferred to use the Gerber format. The quality of the Gerber file output software is typically good, and Gerber supports attributes to transfer meta-information such as plating and span.
IPC-NC-349 format
The IPC-NC-349 format is the only IPC standard governing drill and routing formats. XNC is a strict subset of IPC-NC-349, Excellon a big superset. Many indefinite NC files pick some elements of the IPC standard.
A digital rights managed copy of the specification is available from the IPC website, for a fee. It is targeted at input for drill/rout machines, not CAD to CAM data exchange.
XNC format
The XNC format is strict subset of the IPC-NC-349 specification targeted at data exchange between CAD and CAM. The name XNC format stands for Exchange NC format. As a strict subset, it is highly compatible with existing software. Its purpose is to address the current chaos of different
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https://en.wikipedia.org/wiki/KSTR-DT
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KSTR-DT (channel 49) is a television station licensed to Irving, Texas, United States, broadcasting the Spanish-language UniMás network to the Dallas–Fort Worth metroplex. It is owned and operated by TelevisaUnivision alongside Garland-licensed Univision owned-and-operated station KUVN-DT (channel 23). Both stations share studios on Bryan Street in downtown Dallas, while KSTR-DT's transmitter is located in Cedar Hill, Texas.
History
Early history
The station first signed on the air on April 17, 1984 as KLTJ-TV (the call letters stood for "Keep Looking to Jesus"). Founded by Eldred Thomas, owner of radio station KVTT-FM (91.7, now KKXT), it originally maintained a religious programming format as an affiliate of the Trinity Broadcasting Network (TBN). In early 1986, Thomas sold the station to Silver King Broadcasting, the broadcasting arm of the Home Shopping Network (HSN). As a result of the sale, the station became an affiliate of HSN in September of that year; this left TBN without an outlet in the Dallas–Fort Worth metroplex for the next five months, until it launched owned-and-operated station KDTX-TV (channel 58) in February 1987. On June 1, 1987, the station changed its call letters to KHSX (standing for "Home Shopping in Texas").
On November 27, 1995, veteran television executive Barry Diller announced that he would acquire the Home Shopping Network and Silver King Communications, which owned HSN-affiliated stations in several other larger media markets. The purchase was finalized on December 19, 1996, ten months after the transaction received approval by the Federal Communications Commission (FCC) on March 11. Two years later in 1997, HSN purchased the USA Network, and renamed its broadcast television subsidiary as USA Broadcasting, as part of a corporate rebranding borrowing from the identity of its new cable channel property. That year, KHSX began carrying a one-hour block of programming from business news channel Bloomberg Information Television (now si
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https://en.wikipedia.org/wiki/Murderous%20Maths
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Murderous Maths is a series of British educational books by author Kjartan Poskitt. Most of the books in the series are illustrated by illustrator Philip Reeve, with the exception of "The Secret Life of Codes", which is illustrated by Ian Baker, "Awesome Arithmetricks" illustrated by Daniel Postgate and Rob Davis, and "The Murderous Maths of Everything", also illustrated by Rob Davis.
The Murderous Maths books have been published in over 25 countries. The books, which are aimed at children aged 8 and above, teach maths, spanning from basic arithmetic to relatively complex concepts such as the quadratic formula and trigonometry. The books are written in an informal similar style to the Horrible Histories, Horrible Science and Horrible Geography series, involving evil geniuses, gangsters, and a generally comedic tone.
Development
The first two books of the series were originally part of "The Knowledge" (now "Totally") series, itself a spin-off of Horrible Histories. However, these books were eventually redesigned and they, as well as the rest of the titles in the series, now use the Murderous Maths banner. According to Poskitt, "these books have even found their way into schools and proved to be a boost to GCSE studies". The books are also available in foreign editions, including: German, Spanish, Polish, Czech, Greek, Dutch, Norwegian, Turkish, Croatian, Italian, Lithuanian, Korean, Danish, Hungarian, Finnish, Thai and Portuguese (Latin America). In 2009, the books were redesigned again, changing the cover art style and the titles of most of the books in the series.
Poskitt's goal, according to the Murderous Maths website, is to write books that are "something funny to read", have "good amusing illustrations", include "tricks", and "explaining the maths involved as clearly as possible". He adds that although he doesn't "work to any government imposed curriculum or any stage achievement levels", he has "been delighted to receive many messages of support and thanks
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https://en.wikipedia.org/wiki/Gromov%E2%80%93Witten%20invariant
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In mathematics, specifically in symplectic topology and algebraic geometry, Gromov–Witten (GW) invariants are rational numbers that, in certain situations, count pseudoholomorphic curves meeting prescribed conditions in a given symplectic manifold. The GW invariants may be packaged as a homology or cohomology class in an appropriate space, or as the deformed cup product of quantum cohomology. These invariants have been used to distinguish symplectic manifolds that were previously indistinguishable. They also play a crucial role in closed type IIA string theory. They are named after Mikhail Gromov and Edward Witten.
The rigorous mathematical definition of Gromov–Witten invariants is lengthy and difficult, so it is treated separately in the stable map article. This article attempts a more intuitive explanation of what the invariants mean, how they are computed, and why they are important.
Definition
Consider the following:
X: a closed symplectic manifold of dimension 2k,
A: a 2-dimensional homology class in X,
g: a non-negative integer,
n: a non-negative integer.
Now we define the Gromov–Witten invariants associated to the 4-tuple: (X, A, g, n). Let be the Deligne–Mumford moduli space of curves of genus g with n marked points and denote the moduli space of stable maps into X of class A, for some chosen almost complex structure J on X compatible with its symplectic form. The elements of are of the form:
,
where C is a (not necessarily stable) curve with n marked points x1, ..., xn and f : C → X is pseudoholomorphic. The moduli space has real dimension
Let
denote the stabilization of the curve. Let
which has real dimension . There is an evaluation map
The evaluation map sends the fundamental class of to a d-dimensional rational homology class in Y, denoted
In a sense, this homology class is the Gromov–Witten invariant of X for the data g, n, and A. It is an invariant of the symplectic isotopy class of the symplectic manifold X.
To interpret the Gromov–W
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https://en.wikipedia.org/wiki/Superfecundation
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Superfecundation is the fertilization of two or more ova from the same cycle by sperm from separate acts of sexual intercourse, which can lead to twin babies from two separate biological fathers. The term superfecundation is derived from fecund, meaning able to produce offspring. Homopaternal superfecundation is fertilization of two separate ova from the same father, leading to fraternal twins, while heteropaternal superfecundation is a form of atypical twinning where, genetically, the twins are half siblings – sharing the same mother, but with different fathers.
Conception
Sperm cells can live inside a female's body for up to five days, and once ovulation occurs, the egg remains viable for 12–48 hours before it begins to disintegrate. Superfecundation most commonly happens within hours or days of the first instance of fertilization with ova released during the same cycle.
Ovulation is normally suspended during pregnancy to prevent further ova becoming fertilized and to help increase the chances of a full-term pregnancy. However, if an ovum is atypically released after the female was already impregnated when previously ovulating, a chance of a second pregnancy occurs, albeit at a different stage of development. This is known as superfetation.
Heteropaternal superfecundation
Heteropaternal superfecundation is common in animals such as cats and dogs. Stray dogs can produce litters in which every puppy has a different sire. Though rare in humans, cases have been documented. In one study on humans, the frequency was 2.4% among dizygotic twins whose parents had been involved in paternity suits.
Cases in Greek mythology
Greek mythology holds many cases of superfecundation:
Leda lies with both her husband Tyndareus and with the god Zeus, the latter in the guise of a swan. Nine months later, she bears two daughters: Clytemnestra by Tyndareus and Helen by Zeus. This happens again; this time Leda bears two sons: Castor by Tyndareus and Pollux by Zeus.
Alcmene lies with
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https://en.wikipedia.org/wiki/IBM%20Parallel%20Sysplex
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In computing, a Parallel Sysplex is a cluster of IBM mainframes acting together as a single system image with z/OS. Used for disaster recovery, Parallel Sysplex combines data sharing and parallel computing to allow a cluster of up to 32 systems to share a workload for high performance and high availability.
Sysplex
In 1990, IBM mainframe computers introduced the concept of a Systems Complex, commonly called a Sysplex, with MVS/ESA SPV4.1. This allows authorized components in up to eight logical partitions (LPARs) to communicate and cooperate with each other using the XCF protocol.
Components of a Sysplex include:
A common time source to synchronize all member systems' clocks. This can involve either a Sysplex timer (Model 9037), or the Server Time Protocol (STP)
Global Resource Serialization (GRS), which allows multiple systems to access the same resources concurrently, serializing where necessary to ensure exclusive access
Cross System Coupling Facility (XCF), which allows systems to communicate peer-to-peer
Couple Data Sets (CDS)
Users of a (base) Sysplex include:
Console services – allowing one to merge multiple MCS consoles from the different members of the Sysplex, providing a single system image for Operations
Automatic Restart Manager (ARM) – Policy to direct automatic restart of failed jobs or started tasks on the same system if it is available or on another LPAR in the Sysplex
Sysplex Failure Manager (SFM) – Policy that specifies automated actions to take when certain failures occur such as loss of a member of a Sysplex or when reconfiguring systems
Workload Manager (WLM) – Policy based performance management of heterogeneous workloads across one or more z/OS images or even on AIX
Global Resource Serialization (GRS) - Communication – allows use of XCF links instead of dedicated channels for GRS, and Dynamic RNLs
Tivoli OPC – Hot standby support for the controller
RACF (IBM's mainframe security software product) – Sysplex-wide
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https://en.wikipedia.org/wiki/Logical%20partition
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A logical partition (LPAR) is a subset of a computer's hardware resources, virtualized as a separate computer. In effect, a physical machine can be partitioned into multiple logical partitions, each hosting a separate instance of an operating system.
PR/SM
Formally, LPAR designates the mode of operation or an individual logical partition, whereas PR/SM is the commercial designation of the feature. PR/SM (Processor Resource/System Manager) is a type-1 Hypervisor (a virtual machine monitor) that allows multiple logical partitions to share physical resources such as CPUs, I/O channels and LAN interfaces; when sharing channels, the LPARs can share I/O devices such as direct access storage devices (DASD). PR/SM is integrated with all IBM System z machines. Similar facilities exist on the IBM Power Systems family, and its predecessors.
IBM introduced PR/SM in 1988 with the IBM 3090 processors.
IBM developed the concept of hypervisors in their CP-40 and CP-67, and in 1972 provided it for the S/370 as Virtual Machine Facility/370. IBM introduced the Start Interpretive Execution (SIE) instruction as part of 370-XA on the 3081, and VM/XA versions of VM to exploit it. PR/SM is a type-1 Hypervisor based on the CP component of VM/XA that runs directly on the machine level and allocates system resources across LPARs to share physical resources. It is a standard feature on IBM Z and IBM LinuxONE machines.
IBM introduced a related, simplified, optional feature called Dynamic Partition Manager (DPM) on its IBM z13 and first generation IBM LinuxONE machines. DPM provides Web-based user interfaces for many LPAR-related configuration and monitoring tasks.
History
IBM developed the concept of hypervisors (virtual machines in CP-40 and CP-67) and in 1972 provided it for the S/370 as Virtual Machine Facility/370. IBM introduced the Start Interpretive Execution (SIE) instruction (designed specifically for the execution of virtual machines) as part of 370-XA architecture on the 3081,
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https://en.wikipedia.org/wiki/Kalpana%20%28supercomputer%29
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Kalpana was a supercomputer at NASA Ames Research Center operated by the NASA Advanced Supercomputing (NAS) Division and named in honor of astronaut Kalpana Chawla, who was killed in the Space Shuttle Columbia disaster and had worked as an engineer at Ames Research Center prior to joining the Space Shuttle program. It was built in late 2003 and dedicated on May 12, 2004.
Kalpana was the world's first single-system image (SSI) Linux supercomputer, based on SGI's Altix 3000 architecture and 512 Intel Itanium 2 processors. It was originally built in a joint effort by the NASA Jet Propulsion Laboratory, Ames Research Center (AMC), and Goddard Space Flight Center to perform high-res ocean analysis with the ECCO (Estimating the Circulation and Climate of the Ocean) Consortium model. The supercomputer was "used to develop substantially more capable simulation models to better assess the evolution and behavior of the Earth's climate system," said NASA's Deputy Associate Administrator for Earth Science, Ghassem Asrar in 2004.
It served as one of several testbed systems NASA purchased to determine what architecture to proceed with for new supercomputing projects and lead to the purchase and construction of the Columbia supercomputer, named in honor of the STS-107 crew lost in 2003. In July 2004 the Kalpana system was integrated, as the first node, into the 20-node supercomputer.
References
NASA supercomputers
Ames Research Center
One-of-a-kind computers
Kalpana Chawla
Very long instruction word computing
SGI supercomputers
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https://en.wikipedia.org/wiki/Gross%20anatomy
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Gross anatomy is the study of anatomy at the visible or macroscopic level. The counterpart to gross anatomy is the field of histology, which studies microscopic anatomy. Gross anatomy of the human body or other animals seeks to understand the relationship between components of an organism in order to gain a greater appreciation of the roles of those components and their relationships in maintaining the functions of life. The study of gross anatomy can be performed on deceased organisms using dissection or on living organisms using medical imaging. Education in the gross anatomy of humans is included training for most health professionals.
Techniques of study
Gross anatomy is studied using both invasive and noninvasive methods with the goal of obtaining information about the macroscopic structure and organisation of organs and organ systems. Among the most common methods of study is dissection, in which the corpse of an animal or a human cadaver is surgically opened and its organs studied. Endoscopy, in which a video camera-equipped instrument is inserted through a small incision in the subject, may be used to explore the internal organs and other structures of living animals. The anatomy of the circulatory system in a living animal may be studied noninvasively via angiography, a technique in which blood vessels are visualised after being injected with an opaque dye. Other means of study include radiological techniques of imaging, such as X-ray and MRI.
In medical and healthcare professional education
Most health profession schools, such as medical, physician assistant, and dental schools, require that students complete a practical (dissection) course in gross human anatomy. Such courses aim to educate students in basic human anatomy and seek to establish anatomical landmarks that may later be used to aid medical diagnosis. Many schools provide students with cadavers for investigation by dissection, aided by dissection manuals, as well as cadaveric atlases (e.g. Ne
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https://en.wikipedia.org/wiki/Kalpana%2C%20Inc.
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Kalpana, Inc., was a computer-networking equipment manufacturer located in Silicon Valley which operated during the 1980s and 1990s. Its co-founders, Vinod Bhardwaj, an entrepreneur of Indian origin, and Larry Blair named the company after Bhardwaj's wife, Kalpana, whose name means "imagination" in Sanskrit. Charles Giancarlo was Kalpana's vice president of products and corporate development, became its General Manager, and went on to roles at Cisco Systems and Silver Lake Partners.
In 1989 and 1990, Kalpana introduced the first multiport Ethernet switch, its seven-port EtherSwitch. The invention of Ethernet switching made Ethernet networks faster, cheaper, and easier to manage. Multi-port network switches became common, gradually replacing Ethernet hubs for almost all applications, and enabled an easy transition to 100-megabit Fast Ethernet and later Gigabit Ethernet. Kalpana also invented EtherChannel, which provides higher inter-switch bandwidth by running several links in parallel. This innovation, more generally called link aggregation, was also widely adopted throughout the industry. Kalpana also invented the Virtual LAN concept as closed broadcast domains, which was later replaced by 802.1Q.
Cisco Systems acquired Kalpana in 1994.
Product
Kalpana produced two models of Ethernet switch, the EPS-700 and the EPS-1500.
See also
List of acquisitions by Cisco
References
1987 establishments in California
1994 disestablishments in California
1994 mergers and acquisitions
American companies established in 1987
American companies disestablished in 1994
Cisco Systems acquisitions
Computer companies established in 1987
Computer companies disestablished in 1994
Defunct computer companies of the United States
Defunct computer hardware companies
Defunct networking companies
Networking hardware companies
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https://en.wikipedia.org/wiki/Asepsis
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Asepsis is the state of being free from disease-causing micro-organisms (such as pathogenic bacteria, viruses, pathogenic fungi, and parasites). There are two categories of asepsis: medical and surgical. The modern day notion of asepsis is derived from the older antiseptic techniques, a shift initiated by different individuals in the 19th century who introduced practices such as the sterilizing of surgical tools and the wearing of surgical gloves during operations. The goal of asepsis is to eliminate infection, not to achieve sterility. Ideally, a surgical field is sterile, meaning it is free of all biological contaminants (e.g. fungi, bacteria, viruses), not just those that can cause disease, putrefaction, or fermentation. Even in an aseptic state, a condition of sterile inflammation may develop. The term often refers to those practices used to promote or induce asepsis in an operative field of surgery or medicine to prevent infection.
History
The modern concept of asepsis evolved in the 19th century through multiple individuals. Ignaz Semmelweis showed that hand washing prior to delivery reduced puerperal fever. Despite this, many hospitals continued to practice surgery in unsanitary conditions, with some surgeons taking pride in their bloodstained operating gowns. It was not until after reading of the findings by Louis Pasteur that Joseph Lister introduced the use of carbolic acid as an antiseptic, and in doing so, reduced surgical infection rates. Lawson Tait shifted the movement then from antisepsis to asepsis, instilling practices such as a strict no-talking policy within his operating room and drastically limiting the number of people to come in contact with a patient's wound. Ernst von Bergmann also introduced the autoclave, a device used for the practice of the sterilization of surgical instruments.
But, everything from operating room uniforms to gloves was pioneered by William Halsted. Preceding modern-day scrubs attire, Halsted implemented a no street c
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https://en.wikipedia.org/wiki/Coin%20problem
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The coin problem (also referred to as the Frobenius coin problem or Frobenius problem, after the mathematician Ferdinand Frobenius) is a mathematical problem that asks for the largest monetary amount that cannot be obtained using only coins of specified denominations, for example, the largest amount that cannot be obtained using only coins of 3 and 5 units is 7 units. The solution to this problem for a given set of coin denominations is called the Frobenius number of the set. The Frobenius number exists as long as the set of coin denominations has no common divisor greater than 1.
There is an explicit formula for the Frobenius number when there are only two different coin denominations, and : the Frobenius number is then . If the number of coin denominations is three or more, no explicit formula is known. However, for any fixed number of coin denominations, there is an algorithm for computing the Frobenius number in polynomial time (in the logarithms of the coin denominations forming an input). No known algorithm is polynomial time in the number of coin denominations, and the general problem, where the number of coin denominations may be as large as desired, is NP-hard.
Statement
In mathematical terms, the problem can be stated:
Given positive integers such that gcd, find the largest integer that cannot be expressed as an integer conical combination of these numbers, i.e., as a sum:
where are non-negative integers.
This largest integer is called the Frobenius number of the set , and is usually denoted by
The existence of the Frobenius number depends on the condition that the greatest common divisor (GCD) is equal to 1. Indeed, the potential sums are multiples of the GCD in all cases. Hence, if it is not 1, then there are always arbitrarily large numbers that cannot be obtained as sums. For example, if you had two types of coins valued at 6 cents and 14 cents, the GCD would equal 2, and there would be no way to combine any number of such coins to produce a
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https://en.wikipedia.org/wiki/MBus%20%28SPARC%29
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MBus is a computer bus designed and implemented by Sun Microsystems for communication between high speed computer system components, such as the central processing unit, motherboard and main memory. SBus is used in the same machines to connect add-on cards to the motherboard.
MBus was first used in Sun's first multiprocessor SPARC-based system, the SPARCserver 600MP series (launched in 1991), and later found use in the SPARCstation 10 and SPARCstation 20 workstations. The bus permits the integration of several microprocessors on a single motherboard, in a multiprocessing configuration with up to eight CPUs packaged in detachable MBus modules. In practice, the number of processors per MBus is limited to four. Single processor systems were also sold that use the MBus protocol internally, but with the CPUs permanently attached to the motherboard to lower manufacturing costs.
MBus specifies a 64-bit datapath, which uses 36-bit physical addressing, giving an address space of 64 GB. The transfer rate is 80 MB/s sustained (320 MB/s peak) at 40 MHz, or 100 MB/s (400 MB/s peak) at 50 MHz. Bus controlling is done by an arbiter. Interrupt, reset, and timeout logic are also specified.
Related buses
Several related buses were also developed:
XBus
XBus is a packet-switched bus used in the SPARCserver 1000, SPARCcenter 2000 and Cray CS6400. This corresponds to the circuit-switched MBus, with identical electrical characteristics and physical form factor but an incompatible signalling protocol.
KBus
KBus is a high-speed interconnection system for linking multiple MBuses, used in Solbourne Computer Series 6 and Series 7 computer systems.
History
The MBus standard was cooperatively developed by Sun and Ross Technology and released in 1991.
Manufacturers who produced computer systems using the MBus included Sun, Ross Technology, Hyundai/Axil, Fujitsu, Solbourne Computer, Tatung, GCS, Auspex, ITRI, ICL, Cray, Amdahl, Themis, DTK and Kamstrup.
See also
List of device bandw
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https://en.wikipedia.org/wiki/Lehmer%20sequence
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In mathematics, a Lehmer sequence is a generalization of a Lucas sequence.
Algebraic relations
If a and b are complex numbers with
under the following conditions:
Q and R are relatively prime nonzero integers
is not a root of unity.
Then, the corresponding Lehmer numbers are:
for n odd, and
for n even.
Their companion numbers are:
for n odd and
for n even.
Recurrence
Lehmer numbers form a linear recurrence relation with
with initial values . Similarly the companion sequence satisfies
with initial values
References
Integer sequences
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https://en.wikipedia.org/wiki/Version%206%20Unix
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Sixth Edition Unix, also called Version 6 Unix or just V6, was the first version of the Unix operating system to see wide release outside Bell Labs. It was released in May 1975 and, like its direct predecessor, targeted the DEC PDP-11 family of minicomputers. It was superseded by Version 7 Unix in 1978/1979, although V6 systems remained in regular operation until at least 1985.
AT&T Corporation licensed Version 5 Unix to educational institutions only, but licensed Version 6 also to commercial users for $20,000, and it remained the most widely used version into the 1980s. An enhanced V6 was the basis of the first ever commercially sold Unix version, INTERACTIVE's IS/1. Bell's own PWB/UNIX 1.0 was also based on V6, where earlier (unreleased) versions were based on V4 and V5. Whitesmiths produced and marketed a (binary-compatible) V6 clone under the name Idris.
Source code
V6 Unix was released as a distribution including the full source code. Since source code was available and the license was not explicit enough to forbid it, V6 was taken up as a teaching tool, notably by the University of California, Berkeley, Johns Hopkins University and the University of New South Wales (UNSW).
UC Berkeley distributed a set of add-on programs called the First Berkeley Software Distribution or 1BSD, which later became a complete operating system distribution.
UNSW professor John Lions' famous Commentary on UNIX 6th Edition was an edited selection of the main parts of the kernel as implemented for a Digital PDP-11/40, and was the main source of kernel documentation for many early Unix developers. Due to license restrictions on later Unix versions, the book was mainly distributed by samizdat photo-copying.
The source code for the original V6 Unix was later made available as free software under a BSD License from the SCO Group.
Portability
Interdata 7/32
In 1977, Richard Miller and Ross Nealon, working under the supervision of professor Juris Reinfelds at Wollongong University
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https://en.wikipedia.org/wiki/Videotelephony
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Videotelephony (also known as videoconferencing, video teleconferencing, or simply video call) is the two-way or multipoint reception and transmission of audio and video signals by people in different locations for real-time communication. A videophone is a telephone with a video camera and video display, capable of simultaneous video and audio communication. Videoconferencing implies the use of this technology for a group or organizational meeting rather than for individuals, in a videoconference. Telepresence may refer either to a high-quality videotelephony system (where the goal is to create the illusion that remote participants are in the same room) or to meetup technology, which can go beyond video into robotics (such as moving around the room or physically manipulating objects). Videoconferencing has also been called visual collaboration and is a type of groupware.
While development of video-conferring started in the late 19th century, the technology only became available to the public starting in the 1930s. These early demonstrations were installed at booths in post offices and shown at various world expositions. It took until 1970 for AT&T to launch the first true video-conferring system, where anyone could subscribe to the service and have the technology in their home or office. Videotelephony also included image phones which would exchange still images between units every few seconds over conventional plain old telephone service (POTS) lines, essentially the same as slow-scan TV. The development of advanced video codecs, more powerful CPUs, and high-bandwidth Internet service in the late 1990s allowed videophones to provide high-quality low-cost color service between users almost any place in the world where the Internet is available.
Useful applications include sign language transmission for deaf and speech-impaired people, distance education, telemedicine, and overcoming mobility issues. It is also used in commercial and corporate settings to facilita
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https://en.wikipedia.org/wiki/UDP%20hole%20punching
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UDP hole punching is a commonly used technique employed in network address translation (NAT) applications for maintaining User Datagram Protocol (UDP) packet streams that traverse the NAT. NAT traversal techniques are typically required for client-to-client networking applications on the Internet involving hosts connected in private networks, especially in peer-to-peer, Direct Client-to-Client (DCC) and Voice over Internet Protocol (VoIP) deployments.
UDP hole punching establishes connectivity between two hosts communicating across one or more network address translators. Typically, third-party hosts on the public transit network are used to establish UDP port states that may be used for direct communications between the communicating hosts. Once port state has been successfully established and the hosts are communicating, port state may be maintained either by normal communications traffic, or in the prolonged absence thereof, by keep-alive packets, usually consisting of empty UDP packets or packets with minimal, non-intrusive content.
Overview
UDP hole punching is a method for establishing bidirectional UDP connections between Internet hosts in private networks using network address translators. The technique is not applicable in all scenarios or with all types of NATs, as NAT operating characteristics are not standardized.
Hosts with network connectivity inside a private network connected via a NAT to the Internet typically use the Session Traversal Utilities for NAT (STUN) method or Interactive Connectivity Establishment (ICE) to determine the public address of the NAT that its communications peers require. In this process another host on the public network is used to establish port mapping and other UDP port state that is assumed to be valid for direct communication between the application hosts. Since UDP state usually expires after short periods of time in the range of tens of seconds to a few minutes, and the UDP port is closed in the process, UDP hole pu
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https://en.wikipedia.org/wiki/NAT%20traversal
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Network address translation traversal is a computer networking technique of establishing and maintaining Internet Protocol connections across gateways that implement network address translation (NAT).
NAT traversal techniques are required for many network applications, such as peer-to-peer file sharing and voice over IP.
Network address translation
Network address translation typically uses private IP addresses on private networks with a single public IP address for the router facing the Internet. The network address translator changes the source address in network protocols for outgoing requests from that of an internal device to its external address, so that internal devices can communicate with hosts on the external network, while relaying replies back to the originating device.
This leaves the internal network ill-suited for hosting services, as the NAT device has no automatic method for determining the internal host for which incoming packets from the external network are destined. This is not a problem for general web access and email. However, applications such as peer-to-peer file sharing, VoIP services, and video game consoles require clients to be servers as well. Incoming requests cannot be easily correlated to the proper internal host. Furthermore, many of these types of services carry IP address and port number information in the application data, potentially requiring substitution with deep packet inspection.
Network address translation technologies are not standardized. As a result, the methods used for NAT traversal are often proprietary and poorly documented. Many traversal techniques require assistance from servers outside of the masqueraded network. Some methods use the server only when establishing the connection, while others are based on relaying all data through it, which increases the bandwidth requirements and latency, detrimental to real-time voice and video communications.
NAT traversal techniques usually bypass enterprise security po
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https://en.wikipedia.org/wiki/Alethic%20modality
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Alethic modality (from Greek ἀλήθεια = truth) is a linguistic modality that indicates modalities of truth, in particular the modalities of logical necessity, contingency, possibility and impossibility.
Alethic modality is often associated with epistemic modality in research, and it has been questioned whether this modality should be considered distinct from epistemic modality which denotes the speaker's evaluation or judgment of the truth. The criticism states that there is no real difference between "the truth in the world" (alethic) and "the truth in an individual's mind" (epistemic). An investigation has not found a single language in which alethic and epistemic modalities would be formally distinguished, for example by the means of a grammatical mood. In such a language, "A circle can't be square", "can't be" would be expressed by an alethic mood, whereas for "He can't be that wealthy", "can't be" would be expressed by an epistemic mood. As we can see, this is not a distinction drawn in English grammar.
"You can't give these plants too much water." is a well-known play on the distinction between perhaps alethic and hortatory or injunctive modalities (it can mean either "it is impossible to give these plants too much water = giving them too much water is harmless" or "you must not give these plants too much water = giving them too much water is harmful"). The dilemma is fairly easily resolved when listening through paralinguistic cues and particularly suprasegmental cues (intonation). So while there may not be a morphologically based alethic mood, this does not seem to preclude the usefulness of distinguishing between these two types of modes. Alethic modality might then concern what are considered to be apodictic statements.
References
Grammatical moods
Modal logic
Linguistic modality
Semantics
Modality
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https://en.wikipedia.org/wiki/Optode
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An optode or optrode is an optical sensor device that optically measures a specific substance usually with the aid of a chemical transducer.
Construction
An optode requires three components to function: a chemical that responds to an analyte, a polymer to immobilise the chemical transducer and instrumentation (optical fibre, light source, detector and other electronics). Optodes usually have the polymer matrix coated onto the tip of an optical fibre, but in the case of evanescent wave optodes the polymer is coated on a section of fibre that has been unsheathed.
Operation
Optodes can apply various optical measurement schemes such as reflection, absorption, evanescent wave, luminescence (fluorescence and phosphorescences), chemiluminescence, surface plasmon resonance. By far the most popular methodology is luminescence.
Luminescence in solution obeys the linear Stern–Volmer relationship. Fluorescence of a molecule is quenched by specific analytes, e.g., ruthenium complexes are quenched by oxygen. When a fluorophore is immobilised within a polymer matrix myriad micro-environments are created. The micro-environments reflect varying diffusion co-efficients for the analyte. This leads to a non-linear relationship between the fluorescence and the quencher (analyte). This relationship is modelled in various ways, the most popular model is the two site model created by James Demas (University of Virginia).
The signal (fluorescence) to oxygen ratio is not linear, and an optode is most sensitive at low oxygen concentration, i.e., the sensitivity decreases as oxygen concentration increases. The optode sensors can however work in the whole region 0–100% oxygen saturation in water, and the calibration is done the same way as with the Clark type sensor. No oxygen is consumed and hence the sensor is stirring insensitive, but the signal will stabilize more quickly if the sensor is stirred after being put into the sample.
Popularity
Optical sensors are growing in popularity due
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https://en.wikipedia.org/wiki/Free%20Software%20Foundation%20of%20India
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The Free Software Foundation of India (FSFI) is the Indian sister organisation to the US-based Free Software Foundation. It was founded in Thiruvananthapuram (Trivandrum) (the capital of Kerala) in 2001 as a non-profit Company. The FSFI advocates to promote the use and development of free software in India. This includes educating people about free software, including how it can help the economy of a developing country like India. FSF India regards non-free software as not a solution, but a problem to be solved. Free software is sometimes locally called swatantra software in India.
In 2003, after meeting with FSF founder Richard Stallman, the President of India Dr. Abdul Kalam urged Indian computer scientists and professionals to use free and open-source software in research and development.
Logo
The left side of the FSF India logo resembles the famed Ashoka Chakra, that also appears on the Indian national flag, while its right half is a depiction of a compact disc. The combination of both symbols is intended to draw attention to the similarity between political freedom and free software, the latter of which the FSF promotes.
The Ashoka Chakra, in addition to being a long-standing Buddhist symbol depicting the wheel of time, also resembles Charkha of India's Freedom Struggle and thus in the current context, may symbolize the Indian independence movement which resulted in India's freedom from British occupation.
See also
Free Software Foundation
Free Software Foundation Europe
Free Software Movement of India
Free Software Movement
References
External links
Free Software Foundation of India
A LinuxJournal interview with FSF-India team members
Slashdot and Hindu articles (dated 2002) regarding Stallman's visit to India.
Slashdot and Hindu articles (dated 2002) regarding Dr. Kalam's endorsement of free software.
A Blue-GNU interview: FSF India's Impact Far-Reaching
Free Software Foundation
Organisations based in Thiruvananthapuram
Software industry i
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https://en.wikipedia.org/wiki/Grid%20Security%20Infrastructure
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The Grid Security Infrastructure (GSI), formerly called the Globus Security Infrastructure, is a specification for secret, tamper-proof, delegatable communication between software in a grid computing environment. Secure, authenticatable communication is enabled using asymmetric encryption.
Authentication
Authentication is performed using digital signature technology (see digital signatures for an explanation of how this works); secure authentication allows resources to lock data to only those who should have access to it.
Delegation
Authentication introduces a problem: often a service will have to retrieve data from a resource independent of the user; in order to do this, it must be supplied with the appropriate privileges. GSI allows for the creation of delegated privileges: a new key is created, marked as a delegated and signed by the user; it is then possible for a service to act on behalf of the user to fetch data from the resource.
Security mechanisms
Communications may be secured using a combination of methods:
Transport Layer Security (TLS) can be used to protect the communication channel from eavesdropping or man-in-the-middle attacks.
Message-Level Security can be used (although currently it is much slower than TLS).
References
A Security Infrastructure for Computational Grids by Ian Foster et al.
A National-Scale Authentication Infrastructure by Randy Butler et al.
External links
Overview of the Grid Security Infrastructure
Grid computing
Cryptographic protocols
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https://en.wikipedia.org/wiki/Twist%20compression%20tester
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The Twist Compression Tester ("TCT") is a hydraulically operated bench-top apparatus used to evaluate the level of friction and/or wear between two materials under lubricated or non-lubricated conditions.
Under controlled conditions, a rotating annular specimen is brought into contact with a non-rotating flat specimen. Specimens can be prepared from die materials, sheet or plate materials, metals or plastics.
The applied normal force and the torque are measured, and the coefficient of friction is calculated.
Although the twist-compression test does not simulate an actual process, it has been demonstrated to correlate well with processes where boundary lubrication predominates and lubricant depletion occurs.
The Twist Compression Tester is an invaluable diagnostic tool for: evaluating lubricants, materials and coatings; screening products for production; understanding the effect of additives in a lubricant; and many other value-added testing scenarios.
The Twist Compression Tester was developed by Professor John Schey formerly of the University of Waterloo, and is manufactured, according to his design, under exclusive license by the Industrial Research + Development Institute (Midland, Ontario, Canada). Tribsys is also manufacturing a twist compression machine and other approaches have been used with the Falex MCTT MultiContactTriboTester in thrust-washer configurations.
See also
Tribometer
References
Measuring instruments
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https://en.wikipedia.org/wiki/Nearline%20storage
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Nearline storage (a portmanteau of "near" and "online storage") is a term used in computer science to describe an intermediate type of data storage that represents a compromise between online storage (supporting frequent, very rapid access to data) and offline storage/archiving (used for backups or long-term storage, with infrequent access to data).
Nearline storage dates back to the IBM 3850 Mass Storage System (MSS) tape library, which was announced in 1974.
Overview
The formal distinction between online, nearline, and offline storage is:
Online storage is immediately available for input/output (I/O).
Nearline storage is not immediately available, but can be made online quickly without human intervention.
Offline storage is not immediately available, and requires some human intervention to become online.
For example, always-on spinning hard disk drives are online storage, while spinning drives that spin down automatically, such as in Massive Arrays of Idle Disks (MAID), are nearline storage. Removable media such as tape cartridges that can be automatically loaded, as in tape libraries, are nearline storage, while tape cartridges that must be manually loaded are offline storage.
Robotic nearline storage
The nearline storage system knows on which volume (cartridge) the data resides, and usually asks a robot to retrieve it from this physical location (usually: a tape library or optical jukebox) and put it into a tape drive or optical disc drive to enable access by bringing the data it contains online. This process is not instant, but it only requires a few seconds.
Nearline tape and optical storage has the advantage of relatively longer lifespans compared to spinning hard drives, simply due to the storage media being idle and usually stored in protected dust-free enclosures when not in use. In a robotic tape loading system, the tape drive used for accessing data experiences the most wear and may need occasional replacement, but the tapes themselves can las
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https://en.wikipedia.org/wiki/CD8
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CD8 (cluster of differentiation 8) is a transmembrane glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). Along with the TCR, the CD8 co-receptor plays a role in T cell signaling and aiding with cytotoxic T cell-antigen interactions.
Like the TCR, CD8 binds to a major histocompatibility complex (MHC) molecule, but is specific for the MHC class I protein.
There are two isoforms of the protein, alpha and beta, each encoded by a different gene. In humans, both genes are located on chromosome 2 in position 2p12.
Tissue distribution
The CD8 co-receptor is predominantly expressed on the surface of cytotoxic T cells, but can also be found on natural killer cells, cortical thymocytes, and dendritic cells. The CD8 molecule is a marker for cytotoxic T cell population. It is expressed in T cell lymphoblastic lymphoma and hypo-pigmented mycosis fungoides.
Structure
To function, CD8 forms a dimer, consisting of a pair of CD8 chains. The most common form of CD8 is composed of a CD8-α and CD8-β chain, both members of the immunoglobulin superfamily with an immunoglobulin variable (IgV)-like extracellular domain connected to the membrane by a thin stalk, and an intracellular tail. Less-common homodimers of the CD8-α chain are also expressed on some cells. The molecular weight of each CD8 chain is about 34 kDa. The structure of the CD8 molecule was determined by Leahy, D.J., Axel, R., and Hendrickson, W.A. by X-ray Diffraction at a 2.6A resolution. The structure was determined to have an immunoglobulin-like beta-sandwich folding and 114 amino acid residues. 2% of the protein is wound into α-helices and 46% into β-sheets, with the remaining 52% of the molecules remaining in the loop portions.
Function
The extracellular IgV-like domain of CD8-α interacts with the α3 portion of the Class I MHC molecule. This affinity keeps the T cell receptor of the cytotoxic T cell and the target cell bound closely together during antigen-specific activation. Cytotoxic T cel
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https://en.wikipedia.org/wiki/FitNesse
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FitNesse is a web server, a wiki and an automated testing tool for software. It is based on Ward Cunningham's Framework for Integrated Test and is designed to support acceptance testing rather than unit testing in that it facilitates detailed readable description of system function.
FitNesse allows users of a developed system to enter specially formatted input (its format is accessible to non-programmers). This input is interpreted and tests are created automatically. These tests are then executed by the system and output is returned to the user. The advantage of this approach is very fast feedback from users. The developer of the system to be tested needs to provide some support (classes named "fixtures", conforming to certain conventions).
FitNesse is written in Java (by Micah Martin with help from Robert C. Martin and others). The program first supported only Java, but versions for several other languages have been added over time (C++, Python, Ruby, Delphi, C#, etc.).
Principles of FitNesse
FitNesse as a testing method
FitNesse was originally designed as a highly usable interface around the Fit framework. As such its intention is to support an agile style of black-box testing acceptance and regression testing. In this style of testing the functional testers in a software development project collaborate with the software developers to develop a testing suite.
FitNesse testing is based around the notation of black-box testing, in which a system under test is considered to be a black box and is tested in terms of the outputs generated in response to predetermined inputs. A functional tester is responsible for designing the tests in a functional sense and expressing them within the FitNesse tool, whereas the software developer is responsible for connecting the FitNesse tool to the system under test so that FitNesse can execute the test and compare the actual output to the expected output.
The idea behind this testing method, as described in Fit for Developing
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https://en.wikipedia.org/wiki/Crobots
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Crobots is a programming game released for the first time by Tom Poindexter in December, 1985 as Shareware. It is an MS-DOS program for IBM PC and compatibles and was developed on x86-based Unix systems.
The robots are controlled by a program written in a stripped-down version of C. The robot's mission is to seek out and destroy other robots, each running different programs. The robots can be controlled in order to move around the battlefield, scan the environment to find enemies and fire at enemies using a cannon.
Crobots borrows the concept used from the game RobotWar that ran on the original Apple II computer. Robots were programmed in a proprietary programming language that was interpreted and included a real-time view of the game as it was played.
In October, 2013, Poindexter released the source code of Crobots under the GPLv2 free software license.
Clones
There have been many Crobots clones made. However, very few of them are compiler and virtual machine at the same time; for example there are Java clones that use JVM and C++ clones that use a standard Microsoft compiler.
Proper clones have the same intrinsic functions as the original Tom Poindexter version; sometimes however the direction of angles is changed to match the standard C library's trigonometric functions. The most recent clones are Crobots64 and Netrobots.
Crobots64 by Marco Zora has a C++-subset compiler and a virtual machine with a graphical interface. New capabilities in this clone are cooperation between robots of the same species, the unlimited number of concurrent robots, the floating point math functions and the speed of the virtual CPU.
In contrast, Netrobots can run over a network with each robot running in a separate process, and each robot can be written in a different programming language.
See also
Core War
References
1985 video games
Programming games
Open-source video games
Freeware games
Commercial video games with freely available source code
Video games developed in t
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https://en.wikipedia.org/wiki/Simple%20Common%20Gateway%20Interface
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The Simple Common Gateway Interface (SCGI) is a protocol for applications to interface with HTTP servers, as an alternative to the CGI protocol. It is similar to FastCGI but is designed to be easier to parse. Unlike CGI, it permits a long-running service process to continue serving requests, thus avoiding delays in responding to requests due to setup overhead (such as connecting to a database).
SCGI is a protocol which defines communication between a web server and an application server. This is in contrast to CGI, which is an earlier application (gateway) interface designed to let the application programmer avoid the complexity of sockets and long-running service processes when poor scalability and high overhead are acceptable.
The SCGI protocol leverages the fact that the web server has already parsed and validated the HTTP request, and canonically communicates the request to the SCGI server while letting the application programmer avoid parsing ambiguities and protocol edge cases. This avoids the complicated header-parsing and header-combining rules from RFC 2616, saving significant complexity in the SCGI server process.
History
Neil Schemenauer published the original SCGI protocol specification dated October 2001. He developed the first implementations of SCGI and initially published them in April 2002.
Specification
The client connects to a SCGI server over a reliable stream protocol allowing transmission of 8-bit bytes. The client begins by sending a request. When the SCGI server sees the end of the request it sends back a response and closes the connection. The format of the response is not specifically specified by this protocol, although CGI-equivalent HTTP responses are generally used.
Request format
A SCGI request is the concatenation of netstring-encoded headers and a body. A SCGI response is a normal HTTP response.
Each header consists of a name–value pair, where both the name and the value are null-terminated strings (C strings). The value ca
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https://en.wikipedia.org/wiki/Image%20macro
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An image macro is a piece of digital media featuring a picture, or artwork, with some form of text superimposed. The text frequently appears at the top and bottom of the image. Image macros were one of the most common forms of internet memes in the 2000s, and often featured witty messages or catchphrases, although not all image macros are necessarily humorous. LOLcats, which are images of expressive cats coupled with texts, are considered to be the first notable occurrence of image macros. Advice animal image macros, also referred to as stock-character macros, are also highly associated with the image macro template.
Etymology and use
The term "image macro" originated on the Something Awful forums. The name derived from the fact that the "macros" were a short bit of text a user could enter that the forum software would automatically parse and expand into the code for a pre-defined image. This, in turn, related to the computer science concept of a macroinstruction; "a rule or pattern that specifies how a certain input sequence (often a sequence of characters) should be mapped to an output sequence (also often a sequence of characters) according to a defined procedure".
Beginning in 2007, lolcats and similar image macros (a form of internet phenomenon) spread beyond the initial communities who created them and became widely popular.
Formats
Although they come in many forms, the most common type of image macros consists of:
Text, typically a large text in the Impact font, centered at the top and bottom of the image, usually using all upper-case letters. White text with a black border is typically used because it is easily readable on almost any background color. Typically, the text at the top is only for introduction and the text at the bottom is the main message. Exaggerated, intentional spelling errors are also used frequently for humorous effect.
An image to be placed behind the text. These are typically drawn from a specific set of images that are underst
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https://en.wikipedia.org/wiki/List%20of%20Y-STR%20markers
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The Y-STR markers in the following list are commonly used in forensic and genealogical DNA testing.
DYS454 is the least diverse, and multi-copy marker DYS464 is the most diverse Y-STR marker.
The location on the Y-chromosome of numbered Y-STR markers can be roughly given with cytogenetic localization. For example, DYS449 is located at Yp11.2 - meaning the Y-chromosome, petit arm, band 1, sub-band 1, sub-sub-band 2 - DYS449.
Forensic labs usually use PowerPlex Y (Promega Corporation) and Yfiler (Applied Biosystems) kits that examine 12 or 17 Y-STRs, respectively. Genealogical DNA test labs examine up to 700 Y-STRs.
Mutation rates
Mutation rates are those per generation, as estimated in Chandler (2006). The quoted estimated errors are typically +/- 15-20%. Alternative estimates (for forensic use therefore not all markers are covered) from observed pedigrees are also available at the Y Chromosome Haplotype Reference Database.
It appears that some trinucleotide markers may have much higher mutation rates at some repeat lengths than at others. For example, variation of the trinucleotide DYS388 is generally very slow in most haplogroups, when it takes the values 11–13. But there appears to be much greater variation and more rapid mutation in Haplogroup J, where it typically has values 14–18. Similarly the trinucleotide DYS392 is reported to be "fast" in haplogroups N and Q, where it takes values 14-16 which are rare in other groups.
Y-STR markers
Y-STR allele nomenclatures
DNA testing companies or labs in certain cases use different nomenclatures to designate the same Y-STR allele. Thus, a conversion must be applied in these cases to accurately compare Y-STR results obtained from different companies. The most common nomenclature is based on guidance provided by NIST for Y-STR markers historically reported differently by various companies. The NIST standard is the proposal of ISOGG (International Society of Genetic Genealogy) for genetic genealogy companies.
N
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https://en.wikipedia.org/wiki/Virtual%20displacement
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In analytical mechanics, a branch of applied mathematics and physics, a virtual displacement (or infinitesimal variation) shows how the mechanical system's trajectory can hypothetically (hence the term virtual) deviate very slightly from the actual trajectory of the system without violating the system's constraints. For every time instant is a vector tangential to the configuration space at the point The vectors show the directions in which can "go" without breaking the constraints.
For example, the virtual displacements of the system consisting of a single particle on a two-dimensional surface fill up the entire tangent plane, assuming there are no additional constraints.
If, however, the constraints require that all the trajectories pass through the given point at the given time i.e. then
Notations
Let be the configuration space of the mechanical system, be time instants, consists of smooth functions on , and
The constraints are here for illustration only. In practice, for each individual system, an individual set of constraints is required.
Definition
For each path and a variation of is a function such that, for every and The virtual displacement being the tangent bundle of corresponding to the variation assigns to every the tangent vector
In terms of the tangent map,
Here is the tangent map of where and
Properties
Coordinate representation. If are the coordinates in an arbitrary chart on and then
If, for some time instant and every then, for every
If then
Examples
Free particle in R3
A single particle freely moving in has 3 degrees of freedom. The configuration space is and For every path and a variation of there exists a unique such that as
By the definition,
which leads to
Free particles on a surface
particles moving freely on a two-dimensional surface have degree of freedom. The configuration space here is
where is the radius vector of the particle. It follows that
and every path ma
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https://en.wikipedia.org/wiki/Wizardry%3A%20Proving%20Grounds%20of%20the%20Mad%20Overlord
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Wizardry: Proving Grounds of the Mad Overlord is the first game in the Wizardry series of role-playing video games. It was developed by Andrew Greenberg and Robert Woodhead. In 1980, Norman Sirotek formed Sir-Tech Software, Inc. and launched a beta version of the product at the 1980 Boston Computer Convention. The final version of the game was released in 1981.
The game was one of the first Dungeons & Dragons-style role-playing games to be written for computer play, and the first such game to offer color graphics. It was also the first true party-based role-playing video game. It is now listed among the best video games of all time.
The game ended up as the first of a trilogy that also included Wizardry II: The Knight of Diamonds and Wizardry III: Legacy of Llylgamyn.
Gameplay
Starting in the town, which is represented only as a text-based menu, the player creates a party of up to six characters from an assortment of five possible races (Humans, Elves, Dwarves, Gnomes, Hobbits), three alignments (Good, Neutral, Evil), and four basic classes (Fighter, Priest, Mage, Thief), with four elite classes (Bishop: priest and mage spells; Samurai: fighter with mage spells; Lord: fighter with priest spells, and Ninja: fighter with thief abilities) unlocked once the characters have progressed sufficiently. Good and evil characters normally cannot be assigned to the same party.
After characters are equipped with basic armor and weaponry, the party descends into the dungeon below Trebor's castle. This consists of a maze of ten levels, each progressively more challenging than the last. Classes have multiple spells, each with seven levels, that characters learn as they advance.
The style of play employed in this game has come to be termed a dungeon crawl. The goal, as in most subsequent role-playing video games, is to find treasure including ever more potent items, gain levels of experience by killing monsters, then face the evil arch-wizard Werdna on the bottom level and r
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https://en.wikipedia.org/wiki/The%20Fairyland%20Story
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is a platform arcade video game developed and published by Taito in 1985. In the game, the player controls the witch Ptolemy, with the objective being to clear the screen of all enemies. Ptolemy can use her wand to turn the enemies into large cakes, which she can then push off of platforms onto other enemies, which will squash them and award bonus points. Various Items that increase Ptolemy's projectile radius, as well as kill multiple enemies at the same time, will also appear throughout the stages.
Gameplay has been compared to later Taito platform games, such as Bubble Bobble and The NewZealand Story. It has been ported to various home systems, and has seen releases in various Taito compilations.
Gameplay
The Fairyland Story is a platform arcade game. The player controls the witch Ptolemy through a series of single-screen stages, with the objective being to defeat all of the enemies on each screen. Ptolemy's main weapon is her projectile magic, which will temporarily transform the enemies into large cakes. While in a "caked" form, the enemies can be destroyed either by further magic attacks or by being dropped off a platform, possibly squashing other enemies below. Squashing more than one enemy results in an award of more points and, sometimes, in extra bonuses. 2000 points are awarded for squashing an enemy below a cake, with each additional enemy doubling the number of points awarded. If two or more enemies are killed at once in one spot, a coin will appear in that spot, which may be collected for additional points, and if more are collected, will multiply in points, so as long the player doesn't lose a life.
Ptolemy's enemies are based upon typical fantasy beings - these include Orcs, pig-like soldiers, Salamanders, dragon-like creatures that can breathe fire, Wizards, mages that can make Ptolemy shrink and disappear, Clerics, bishops who can multiply themselves, Golems, and Wraiths, hooded creatures can phase through Ptolemy's magic. If Ptolemy takes too
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https://en.wikipedia.org/wiki/Profiling%20%28computer%20programming%29
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In software engineering, profiling ("program profiling", "software profiling") is a form of dynamic program analysis that measures, for example, the space (memory) or time complexity of a program, the usage of particular instructions, or the frequency and duration of function calls. Most commonly, profiling information serves to aid program optimization, and more specifically, performance engineering.
Profiling is achieved by instrumenting either the program source code or its binary executable form using a tool called a profiler (or code profiler). Profilers may use a number of different techniques, such as event-based, statistical, instrumented, and simulation methods.
Gathering program events
Profilers use a wide variety of techniques to collect data, including hardware interrupts, code instrumentation, instruction set simulation, operating system hooks, and performance counters.
Use of profilers
The output of a profiler may be:
A statistical summary of the events observed (a profile)
Summary profile information is often shown annotated against the source code statements where the events occur, so the size of measurement data is linear to the code size of the program.
/* ------------ source------------------------- count */
0001 IF X = "A" 0055
0002 THEN DO
0003 ADD 1 to XCOUNT 0032
0004 ELSE
0005 IF X = "B" 0055
A stream of recorded events (a trace)
For sequential programs, a summary profile is usually sufficient, but performance problems in parallel programs (waiting for messages or synchronization issues) often depend on the time relationship of events, thus requiring a full trace to get an understanding of what is happening.
The size of a (full) trace is linear to the program's instruction path length, making it somewhat impractical. A trace may therefore be initiated at one point in a
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https://en.wikipedia.org/wiki/The%20Research%20and%20Analysis%20Center
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The Research and Analysis Center (TRAC), formerly the TRADOC Analysis Center, is an analysis agency of the United States Army. TRAC conducts research on potential military operations worldwide to inform decisions about the most challenging issues facing the Army and the Department of Defense (DoD). TRAC relies upon the intellectual capital of a highly skilled workforce of military and civilian personnel to execute its mission.
TRAC conducts operations research (OR) on a wide range of military topics, some contemporary but most often set five to 15 years in the future. TRAC directly supports the mission of the Army Futures Command (AFC), to develop future concepts and requirements while also serving the decision needs of many military clients.
Mission statement
To produce relevant and credible operations analysis to inform decisions.
Organization
TRAC is led by a civilian SES director, subordinate to the Commanding General of the US Army Futures Command. It comprises four centers:
TRAC-Fort Leavenworth (TRAC-FLVN), led by a civilian SES director, is co-located with TRAC headquarters at Fort Leavenworth, Kansas and has traditionally conducted analysis at the operational (Corps and division) level.
TRAC-White Sands Missile Range (TRAC-WSMR), led by a civilian SES director, is located at White Sands Missile Range in New Mexico and has traditionally conducted analysis at the tactical Brigade and below level.
TRAC-LEE, led by a led by a lieutenant colonel, is co-located with the Combined Arms Support Command (CASCOM) located at Fort Lee, VA and has traditionally conducted analysis in the area of Sustainment, which includes Logistics and other support functions such as medical and personnel.
TRAC-Monterey, also led by a lieutenant colonel, is co-located with the Naval Postgraduate School (NPS) in Monterey, CA and has traditionally utilized the resources of NPS to conduct research into new models and methodologies.
Each center director is subordinate to the TRA
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https://en.wikipedia.org/wiki/Chuvash%20numerals
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Chuvash numerals is an ancient numeral system from the Old Turkic script the Chuvash people used. (Modern Chuvash use Hindu-Arabic numerals.)
Those numerals originate from finger numeration. They look like Roman numerals, but larger numerals stay at the right side. It was possible to carve those numerals on wood. In some cases numerals were preserved until the beginning of the 20th century.
Examples
References
Numerals
Numeral systems
Numerals
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https://en.wikipedia.org/wiki/Gauss%27s%20lemma%20%28number%20theory%29
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Gauss's lemma in number theory gives a condition for an integer to be a quadratic residue. Although it is not useful computationally, it has theoretical significance, being involved in some proofs of quadratic reciprocity.
It made its first appearance in Carl Friedrich Gauss's third proof (1808) of quadratic reciprocity and he proved it again in his fifth proof (1818).
Statement of the lemma
For any odd prime let be an integer that is coprime to .
Consider the integers
and their least positive residues modulo . These residues are all distinct, so there are ( of them.
Let be the number of these residues that are greater than . Then
where is the Legendre symbol.
Example
Taking = 11 and = 7, the relevant sequence of integers is
7, 14, 21, 28, 35.
After reduction modulo 11, this sequence becomes
7, 3, 10, 6, 2.
Three of these integers are larger than 11/2 (namely 6, 7 and 10), so = 3. Correspondingly Gauss's lemma predicts that
This is indeed correct, because 7 is not a quadratic residue modulo 11.
The above sequence of residues
7, 3, 10, 6, 2
may also be written
−4, 3, −1, −5, 2.
In this form, the integers larger than 11/2 appear as negative numbers. It is also apparent that the absolute values of the residues are a permutation of the residues
1, 2, 3, 4, 5.
Proof
A fairly simple proof, reminiscent of one of the simplest proofs of Fermat's little theorem, can be obtained by evaluating the product
modulo p in two different ways. On one hand it is equal to
The second evaluation takes more work. If is a nonzero residue modulo , let us define the "absolute value" of to be
Since counts those multiples which are in the latter range, and since for those multiples, is in the first range, we have
Now observe that the values are distinct for . Indeed, we have
because is coprime to .
This gives = , since and are positive least residues. But there are exactly of them, so their values are a rearrangement of the integers . Therefore,
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https://en.wikipedia.org/wiki/Parallel%20terraced%20scan
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The parallel terraced scan is a multi-agent based search technique that is basic to cognitive architectures, such as Copycat, Letter-string, the Examiner, Tabletop, and others. It was developed by John Rehling and Douglas Hofstadter at the Center for Research on Concepts and Cognition at Indiana University, Bloomington.
The parallel terraced scan builds on the concepts of the workspace, coderack, conceptual memory, and temperature. According to Hofstadter the parallel and random nature of the processing captures aspects of human cognition.
See also
Copycat
External links
The Parallel Terraced Scan: An Optimization For An Agent-Oriented Architecture (pdf)
Cognitive architecture
Theory of computation
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https://en.wikipedia.org/wiki/Richard%20Turner%20%28computer%20scientist%29
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Richard Turner (born 1954) is a distinguished service professor in the School of Systems and Enterprises of Stevens Institute of Technology in Hoboken, New Jersey.
Turner has a BA in mathematics from Huntingdon College, an MS in computer science from the University of Louisiana-Lafayette, and a DSc in engineering management from the George Washington University.
Before joining Stevens, he was a Fellow of the Systems and Software Consortium Inc., a Research Professor at The George Washington University, a computer scientist at the Federal Aviation Administration, and technical manager and practitioner with various DC area businesses working with defense, intelligence, and commercial clients. He has also served as a visiting scientist at the Software Engineering Institute of Carnegie Mellon University, and consulted independently.
Much of his research at Stevens has been through the Systems Engineering Research Center (SERC) supporting the U.S. Department of Defense, particularly on the integration of systems and software engineering and the acquisition of complex defense systems. He was on the original author team of the CMMI and a core author of the Software Extension to the Guide to the Project Management Body of Knowledge PMI and IEEE Computer Society.
He is a Senior Member of the IEEE, a Golden Core Awardee of the IEEE Computer Society, and a Fellow of the Lean Systems Society.
He has authored / co authored several books:-
The Incremental Commitment Spiral Model: Principles and Practices for Successful Systems and Software, by Barry Boehm, Jo Ann Lane, Supannika Koolmanojwong, and Richard Turner: Addison-Wesley, (2014).
CMMI (Capability Maturity Model Integration) Distilled: A Practical Introduction to Integrated Process Improvement, by Dennis M. Ahern, Aaron Clouse, Richard Turner: Addison-Wesley, (Third Edition 2008).
CMMI Survival Guide: Just enough process improvement, by Suzanne Garcia, Richard Turner: Addison-Wesley, (2007).
Balancing Agility
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https://en.wikipedia.org/wiki/WMOR-TV
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WMOR-TV (channel 32) is an independent television station licensed to Lakeland, Florida, United States, serving the Tampa Bay area. Owned by Hearst Television, the station maintains studios on Hillsborough Avenue in east Tampa, and its transmitter is located in Riverview. Master control and some internal operations are based at the studios of Orlando NBC affiliate WESH (channel 2) on North Wymore Road in Eatonville.
WMOR-TV is the only television station owned by Hearst that is not affiliated with any major broadcast network, as well as the only Hearst station that does not maintain a news department. Despite Lakeland being WMOR-TV's city of license, the station has no physical presence there.
History
The station first signed on the air on April 24, 1986, as WTMV; branded as "V-32", it originally maintained an all-music video format. The station's owner and general manager was Dan Johnson, former mayor of St. Petersburg Beach, who previously owned the old WXCR-FM classical music radio station in nearby Safety Harbor. The station originally operated from studio facilities located on South Florida Avenue/SR 37 on the south side of Lakeland, with its transmitter near Mulberry in southwestern Polk County.
After a brief period of broadcasting from its transmitter in Mulberry, WTMV relocated its studio operations to its present-day studios in Tampa in 1988. The facility had been a former headend office for Group W Cable's Hillsborough County system. Around this time, it transitioned to a conventional general entertainment format, filling a void left by WFTS-TV's switch to Fox. It aired a schedule of off-network and syndicated sitcoms and dramas, game shows, movies and cartoons. It also picked up several network programs from ABC, NBC and CBS that Tampa Bay's Big Three affiliates (WTSP channel 10 (now with CBS), WFLA-TV channel 8, and WTVT channel 13 (now with Fox)) as well as those from Orlando (WFTV channel 9, WESH, WCPX (now WKMG-TV), channel 6) chose to preempt.
WT
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https://en.wikipedia.org/wiki/Endogenous%20retrovirus
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Endogenous retroviruses (ERVs) are endogenous viral elements in the genome that closely resemble and can be derived from retroviruses. They are abundant in the genomes of jawed vertebrates, and they comprise up to 5–8% of the human genome (lower estimates of ~1%).
ERVs are a vertically inherited proviral sequence and a subclass of a type of gene called a transposon, which can normally be packaged and moved within the genome to serve a vital role in gene expression and in regulation. ERVs however lack most transposon functions, are typically not infectious and are often defective genomic remnants of the retroviral replication cycle. They are distinguished as germline provirus retroelements due to their integration and reverse-transcription into the nuclear genome of the host cell.
Researchers have suggested that retroviruses evolved from a type of transposon called a retrotransposon, a Class I element; these genes can mutate and instead of moving to another location in the genome they can become exogenous or pathogenic. This means that not all ERVs may have originated as an insertion by a retrovirus but that some may have been the source for the genetic information in the retroviruses they resemble. When integration of viral DNA occurs in the germ-line, it can give rise to an ERV, which can later become fixed in the gene pool of the host population.
Formation
The replication cycle of a retrovirus entails the insertion ("integration") of a DNA copy of the viral genome into the nuclear genome of the host cell. Most retroviruses infect somatic cells, but occasional infection of germline cells (cells that produce eggs and sperm) can also occur. Rarely, retroviral integration may occur in a germline cell that goes on to develop into a viable organism. This organism will carry the inserted retroviral genome as an integral part of its own genome—an "endogenous" retrovirus (ERV) that may be inherited by its offspring as a novel allele. Many ERVs have persisted in the g
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https://en.wikipedia.org/wiki/National%20research%20and%20education%20network
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A national research and education network (NREN) is a specialised internet service provider dedicated to supporting the needs of the research and education communities within a country.
It is usually distinguished by support for a high-speed backbone network, often offering dedicated channels for individual research projects.
In recent years NRENs have developed many 'above the net' services.
List of NRENs by geographic area
East and Southern Africa
UbuntuNet Alliance for Research and Education Networking - the Alliance of NRENs of East and Southern Africa
Eb@le - DRC NREN
EthERNet - Ethiopian NREN
iRENALA - Malagasy NREN
KENET - Kenyan NREN
MAREN - Malawian NREN
MoRENet - Mozambican NREN
RENU - Ugandan NREN
RwEdNet - Rwanda NREN
SomaliREN - Somali NREN
SudREN - Sudanese NREN
TENET/SANReN - South African NREN
TERNET - Tanzanian NREN
Xnet - Namibian NREN
ZAMREN - Zambian NREN
North Africa
ASREN - Arab States Research and Education Network
TUREN - Tunisian NREN
MARWAN - Moroccan NREN
ENREN - Egyptian NREN
ARN (Algeria) - Algerian NREN
SudREN - Sudanese NREN
SomaliREN - Somali NREN
West and Central Africa
WACREN - West and Central African Research and Education Network
GARNET - Ghanaian NREN
TogoRER - Togolese NREN
GhREN - Ghanaian NREN
MaliREN - Mali NREN
Niger-REN - Nigerien NREN
RITER - Côte d'Ivoire NREN
SnRER - Senegalese NREN
NgREN - Nigerian NREN
Eko-Konnect Research and Education Network - Nigerian NREN
LRREN - Liberia Research and Education Network
Asia Pacific
APAN - Asia-Pacific Advanced Network
AARNet - Australian NREN
AfgREN - Afghanistan NREN
BDREN - Bangladeshi NREN
CSTNET - China Science and Technology Network
CERNET - China Education and Research Network
ERNET - Indian NREN
HARNET - Hong Kong NREN
KOREN - Korean NREN
KREONET- Korean NREN
IDREN - Indonesian NREN
LEARN - Sri Lankan NREN
SINET - Japanese NREN
MYREN - Malaysian NREN
NKN - Indian NREN
NREN - Nepal NREN
NREN - Islamic Republic of Iran N
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https://en.wikipedia.org/wiki/UEFI%20Forum
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UEFI Forum, Inc. is an alliance between technology companies to coordinate the development of the UEFI specifications. The board of directors includes representatives from twelve promoter companies: AMD, American Megatrends, ARM, Apple, Dell, Hewlett Packard Enterprise, HP Inc., Insyde Software, Intel, Lenovo, Microsoft, and Phoenix Technologies.
Overview
The non-profit corporation has assumed responsibility for the management and promotion of the Unified Extensible Firmware Interface (UEFI) specification, a bootloader and runtime interface between platform firmware and an operating system. The original EFI specification was developed by Intel and was used as the starting point from which the UEFI version(s) were developed. The goal of the organization is to replace the aging PC BIOS.
In addition to the UEFI specification, the forum is responsible for a UEFI Platform Initialization (PI) specification, which addresses the firmware internal architecture as well as firmware-to-hardware interfaces. The forum also is responsible for Self-Certification Test suites, which defines conformance to the specifications that it defines.
In October 2013, the Advanced Configuration and Power Interface (ACPI) assets have also been transferred into the forum. The forum is responsible for the management and promotion of future ACPI specifications, which provides static tables at boot time and dynamic control methods as the primary runtime interfaces between the OS and system firmware for system configuration, power management and RAS (Reliability, Availability and Supportability) features. ACPI "Revision 5.0" is used as the starting point from which future ACPI version(s) will be developed.
Published specifications
UEFI Specification version 2.8, published March, 2019
UEFI Shell Specification version 2.2, published January 26, 2016
UEFI Platform Initialization Specification version 1.7, published January, 2019
UEFI Platform Initialization Distribution Packaging Specification
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https://en.wikipedia.org/wiki/Electropherogram
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An electropherogram, or electrophoretogram, can also be referred to as an EPG or e-gram. It is a record or chart produced when electrophoresis is used in an analytical technique, primarily in the fields of forensic biology, molecular biology and biochemistry. The method utilizes data points that correspond with a specific time and fluorescence intensity at various wavelengths of light to represent a DNA profile.
In the field of genetics, an electropherogram is a plot of DNA fragment sizes, typically used for genotyping such as DNA sequencing. The data is plotted with time, shown via base pairs (bps), on the x-axis and fluorescence intensity on the y-axis. Such plots are often achieved using an instrument such as an automated DNA sequencer paired with capillary electrophoresis (CE). Such electropherograms may be used to determine DNA sequence genotypes, or genotypes that are based on the length of specific DNA fragments or number of short tandem repeats (STR) at a specific locus by comparing the sample to internal size standards and allelic ladder data using the same size standard. These genotypes can be used for:
genealogical DNA testing
DNA paternity testing
DNA profiling
phylogenetics
population genetics
See also
Gel electrophoresis of nucleic acids
References
External links
PHPH — web-based tool for electropherogram quality analysis
Systematic differences in electropherogram peak heights reported by different versions of the GeneScan Software
DYS464 Electropherogram Interpretation Discrepancy with images
Applied genetics
Biometrics
DNA
Genetic genealogy
Genetics techniques
Laboratory techniques
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https://en.wikipedia.org/wiki/Bioprocess
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A bioprocess is a specific process that uses complete living cells or their components (e.g., bacteria, enzymes, chloroplasts) to obtain desired products.
Transport of energy and mass is fundamental to many biological and environmental processes. Areas, from food processing (including brewing beer) to thermal design of buildings to biomedical devices, manufacture of monoclonal antibodies to pollution control and global warming, require knowledge of how energy and mass can be transported through materials (momentum, heat transfer, etc.).
Cell bioprocessing
Cell therapy bioprocessing is a discipline that bridges the fields of cell therapy and bioprocessing (i.e., biopharmaceutical manufacturing), and is a sub-field of bioprocess engineering. The goals of cell therapy bioprocessing are to establish reproducible and robust manufacturing processes for the production of therapeutic cells. Commercially relevant bioprocesses will:
Produce products that maintain all of the quality standards of biopharmaceutical drugs
Supply both clinical and commercial quantities of therapeutic cells throughout the various stages of development. The processes and production technologies must be scalable, and
Control the cost of goods (CoGs) of the final drug product. This aspect is critical to building the foundation for a commercially viable industry.
Upstream bioprocessing
Therapeutic cell manufacturing processes can be separated into upstream processes and downstream processes. The upstream process is defined as the entire process from early cell isolation and cultivation, to cell banking and culture expansion of the cells until final harvest (termination of the culture and collection of the live cell batch).
Aside from technology challenges, concerning the scalability of culture apparatus, a number of raw material supply risks have emerged in recent years, including the availability of GMP grade fetal bovine serum.
The upstream part of a bioprocess refers to the first step
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https://en.wikipedia.org/wiki/INDICARE
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Goal
The overall goal of INDICARE (The INformed DIalogue about Consumer Acceptability of DRM Solutions in Europe) was to help to reconcile heterogeneous interests of multiple stakeholders, and to support the emergence of a common European position with regard to consumer and user issues of Digital Rights Management (DRM) solutions.
eContent
INDICARE responded to the 3rd call, subline 3.3: Management of rights for digital content, of the eContent Programme of the European Commission, DG Information Society. INDICARE, a so-called Accompanying Measure, was initiated March 2004 and was scheduled for two years (Ref.: EDC - 53042 INDICARE / 28609). eContent was replaced by eContentplus as of 9 March 2005.
Focus
INDICARE addresses problems pointed out in the eContent Work Programme 2003–2004: “There has been little attention to the consumer side of managing rights. Questions remain open as to the level of consumer acceptability of rights management solutions. Interface and functionality of systems, as well as policy issues linked to privacy and access to information should be the investigated. The consumer question also involves the easiness of access, the legitimate use of content and business models and the easiness of access for disabled persons” (p. 19). In addition to consumer issues, INDICARE addresses the user side, in particular concerns of creators and small and medium-sized information providers.
Approach
The INDICARE project establishes and maintains an informed dialogue about consumer and user issues of DRM. Informed dialogue means that discussions will be stimulated and informed by good quality input such as news information and profound analyses (see below). Part of the input will be derived from interdisciplinary in-depth research of the INDICARE partners as well as from knowledge of experts and stakeholders co-operating with INDICARE.
External links
INDICARE website with all publications
eContent Work Programme 2003–2004
eContentplus
Projec
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https://en.wikipedia.org/wiki/Direct-attached%20storage
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Direct-attached storage (DAS) is digital storage directly attached to the computer accessing it, as opposed to storage accessed over a computer network (i.e. network-attached storage). DAS consists of one or more storage units such as hard drives, solid-state drives, optical disc drives within an external enclosure. The term "DAS" is a retronym to contrast with storage area network (SAN) and network-attached storage (NAS).
Features
A typical DAS system is made of a data storage device (for example enclosures holding a number of hard disk drives) connected directly to a computer through a host bus adapter (HBA). Between those two points there is no network device (like hub, switch, or router), and this is the main characteristic of DAS.
The main protocols used for DAS connections are ATA, SATA, eSATA, NVMe, SCSI, SAS, USB, USB 3.0 and IEEE 1394.
Storage features of SAN, DAS, and NAS
Most functions found in modern storage do not depend on whether the storage is attached directly to servers (DAS), or via a network (SAN and NAS). In enterprise environments, direct-attached storage systems can utilize storage devices that have higher endurance in terms of data workload capability, along with scalability in the amount of capacity that storage arrays can achieve compared to NAS and other consumer-graded storage devices.
Advantages and disadvantages
The key difference between DAS and NAS is that DAS storage does not incorporate any network hardware and related operating environment to provide a facility to share storage resources independently of the host so is only available via the host to which the DAS is attached.
DAS is typically considered much faster than NAS due to lower latency in the type of host connection although contemporary network and direct connection throughput typically exceeds the raw read/write performance of the storage units themselves.
A SAN (storage area network) has more in common with a DAS than a NAS with the key difference being that DA
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https://en.wikipedia.org/wiki/Hopanoids
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Hopanoids are a diverse subclass of triterpenoids with the same hydrocarbon skeleton as the compound hopane. This group of pentacyclic molecules therefore refers to simple hopenes, hopanols and hopanes, but also to extensively functionalized derivatives such as bacteriohopanepolyols (BHPs) and hopanoids covalently attached to lipid A.
The first known hopanoid, hydroxyhopanone, was isolated by two chemists at The National Gallery, London working on the chemistry of dammar gum, a natural resin used as a varnish for paintings. While hopanoids are often assumed to be made only in bacteria, their name actually comes from the abundance of hopanoid compounds in the resin of plants from the genus Hopea. In turn, this genus is named after John Hope, the first Regius Keeper of the Royal Botanic Garden, Edinburgh.
Since their initial discovery in an angiosperm, hopanoids have been found in plasma membranes of bacteria, lichens, bryophytes, ferns, tropical trees and fungi. Hopanoids have stable polycyclic structures that are well-preserved in petroleum reservoirs, rocks and sediment, allowing the diagenetic products of these molecules to be interpreted as biomarkers for the presence of specific microbes and potentially for chemical or physical conditions at the time of deposition. Hopanoids have not been detected in archaea.
Biological function
About 10% of sequenced bacterial genomes have a putative shc gene encoding a squalene-hopene cyclase and can presumably make hopanoids, which have been shown to play diverse roles in the plasma membrane and may allow some organisms to adapt in extreme environments.
Since hopanoids modify plasma membrane properties in bacteria, they are frequently compared to sterols (e.g., cholesterol), which modulate membrane fluidity and serve other functions in eukaryotes. Although hopanoids do not rescue sterol deficiency, they are thought to increase membrane rigidity and decrease permeability. Also, gammaproteobacteria and eukaryotic organisms
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https://en.wikipedia.org/wiki/In%20situ%20hybridization
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In situ hybridization (ISH) is a type of hybridization that uses a labeled complementary DNA, RNA or modified nucleic acids strand (i.e., probe) to localize a specific DNA or RNA sequence in a portion or section of tissue (in situ) or if the tissue is small enough (e.g., plant seeds, Drosophila embryos), in the entire tissue (whole mount ISH), in cells, and in circulating tumor cells (CTCs). This is distinct from immunohistochemistry, which usually localizes proteins in tissue sections.
In situ hybridization is used to reveal the location of specific nucleic acid sequences on chromosomes or in tissues, a crucial step for understanding the organization, regulation, and function of genes. The key techniques currently in use include in situ hybridization to mRNA with oligonucleotide and RNA probes (both radio-labeled and hapten-labeled), analysis with light and electron microscopes, whole mount in situ hybridization, double detection of RNAs and RNA plus protein, and fluorescent in situ hybridization to detect chromosomal sequences. DNA ISH can be used to determine the structure of chromosomes. Fluorescent DNA ISH (FISH) can, for example, be used in medical diagnostics to assess chromosomal integrity. RNA ISH (RNA in situ hybridization) is used to measure and localize RNAs (mRNAs, lncRNAs, and miRNAs) within tissue sections, cells, whole mounts, and circulating tumor cells (CTCs). In situ hybridization was invented by American biologists Mary-Lou Pardue and Joseph G. Gall.
Challenges of in-situ hybridization
In situ hybridization is a powerful technique for identifying specific mRNA species within individual cells in tissue sections, providing insights into physiological processes and disease pathogenesis. However, in situ hybridization requires that many steps be taken with precise optimization for each tissue examined and for each probe used. In order to preserve the target mRNA within tissues, it is often required that crosslinking fixatives (such as formaldehyde
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https://en.wikipedia.org/wiki/Lexra
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Lexra (1997–2003) was a semiconductor intellectual property core company based in Waltham, Massachusetts. Lexra developed and licensed semiconductor intellectual property cores that implemented the MIPS I architecture, except for the four unaligned load and store (lwl, lwr, swl, swr) instructions.
Lexra did not implement those instructions because they are not necessary for good performance in modern software. Silicon Graphics owned a patent that was initially granted to MIPS Computer Systems Inc. for implementing unaligned loads and stores in a RISC processor. Lexra did not wish to pay a high license fee for permission to use the patent.
Lexra licensed soft cores, unlike ARM Ltd at the time. Lexra was probably the first semiconductor intellectual property core company to do so.
In 1998 Silicon Graphics spun out MIPS Technologies Inc. as a semiconductor IP licensing company that would compete directly with Lexra. MIPS Technologies soon sued Lexra, asserting trademark infringement by Lexra's claims of compatibility with MIPS I. Lexra and MIPS Technologies settled the dispute by agreeing that Lexra would explicitly describe its products as not implementing unaligned loads and stores.
In 1999, MIPS Technologies sued Lexra again, but this time for infringing its patents on unaligned loads and stores. Though Lexra's processor designs did not implement unaligned loads and stores, it was possible to emulate their functionality through a series of other instructions. The ability to emulate the function of unaligned loads and stores was used, for example, in microcode for IBM mainframes long before the application for MIPS Technologies' patent. Lexra contended that the patent was invalid if construed to cover software emulation of unaligned loads and stores. If construed to cover only hardware implementations, Lexra did not infringe. The protracted second lawsuit, combined with a downturn in semiconductor industry business, forced Lexra into a settlement with MIPS Techno
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https://en.wikipedia.org/wiki/Michel%20de%20Castelnau
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Michel de Castelnau, Sieur de la Mauvissière (c. 1520–1592) was a French soldier and diplomat, ambassador to Queen Elizabeth. He wrote a memoir covering the period between 1559 and 1570.
Life
He was born in La Mauvissière (now part of Neuvy-le-Roi, Indre-et-Loire), Touraine about 1520. He was a son of Jean de Castelnau and Jeanne Dusmesnil, one of a family of nine children. His grandfather, Pierre de Castelnau, had been Equerry (Master of the Horse) to Louis XII.
Endowed with a clear and penetrating intellect and remarkable strength of memory, he received a careful education, capped off with travels in Italy and a long stay at Rome. He then spent some time in Malta and afterwards entered the army. His first acquaintance with war was in the campaigns of the French in Italy. His abilities and his courage won him the friendship and protection of Charles, Cardinal of Lorraine, who took him into his service.
In 1557 a command in the navy was given to him, and the cardinal proposed to get him knighted. This, however, he declined, and then rejoined the French army in Picardy. Various delicate missions requiring tact and discretion were entrusted to him by the Constable, Anne de Montmorency, and these he discharged so satisfactorily that he was sent by the king, Henry II, to Scotland with dispatches for Mary of Guise, the mother of Mary, Queen of Scots, who was betrothed to the Dauphin (afterwards Francis II).
From Scotland he passed into England in 1559, and treated with Queen Elizabeth respecting her claims on Calais, a settlement of which was effected at the congress of Le Cateau-Cambrésis. He was next sent as ambassador to the princes of Germany, for the purpose of prevailing upon them to withdraw their favor from the Protestants. This embassy was followed by missions to Margaret of Austria, governess of the Netherlands, to Savoy, and then to Rome, to ascertain the views of Pope Paul IV in regard to France. Paul having died just before his arrival, Castelnau used hi
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https://en.wikipedia.org/wiki/YaCy
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YaCy (pronounced “ya see”) is a free distributed search engine, built on the principles of peer-to-peer (P2P) networks created by Michael Christen in 2003. The engine is written in Java and distributed on several hundred computers, , so-called YaCy-peers. Each YaCy-peer independently crawls through the Internet, analyzes and indexes found web pages, and stores indexing results in a common database (so-called index) which is shared with other YaCy-peers using principles of peer-to-peer. It is a search engine that everyone can use to build a search portal for their intranet and to help search the public internet clearly.
Compared to semi-distributed search engines, the YaCy-network has a distributed architecture. All YaCy-peers are equal and no central server exists. It can be run either in a crawling mode or as a local proxy server, indexing web pages visited by the person running YaCy on their computer. Several mechanisms are provided to protect the user's privacy. Access to the search functions is made by a locally run web server which provides a search box to enter search terms, and returns search results in a similar format to other popular search engines.
System components
YaCy search engine is based on four elements:
Crawler A search robot that traverses between web pages, analyzing their content.
Indexer It creates a reverse word index (RWI), i.e., each word from the RWI has its own list of relevant URLs and ranking information. Words are saved in the form of word hashes.
Search and administration interface Made as a web interface provided by a local HTTP servlet with servlet engine.
Data storage Used to store the reverse word index database utilizing a distributed hash table.
Search-engine technology
YaCy is a complete search appliance with user interface, index, administration and monitoring.
YaCy harvests web pages with a web crawler. Documents are then parsed, indexed and the search index is stored locally. If your peer is part of a peer network, t
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https://en.wikipedia.org/wiki/Digital%20sum%20in%20base%20b
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The digital sum in base b of a set of natural numbers is calculated as follows: express each of the numbers in base b, then take the sum of corresponding digits and discard all carry overs. That is, the digital sum is the same as the normal sum except that no carrying is used.
For example, in decimal (base 10) arithmetic, the digital sum of 123 and 789 is 802:
3 + 9 = 12, discard the 10 leaving 2.
2 + 8 = 10, discard the 10 leaving 0.
1 + 7 = 8, there is no carry to discard.
123
789
---
802
More usually the digital sum is calculated in binary (base 2) where the result only depends upon whether there are an even or odd number of 1s in each column. This is the same function as parity or multiple exclusive ors.
For example:
011 (3)
100 (4)
101 (5)
---
010 (2) is the binary digital sum of 3, 4 and 5.
The binary digital sum is crucial for the theory of the game of Nim.
The digital sum in base b is an associative and commutative operation on the natural numbers; it has 0 as neutral element and every natural number has an inverse element under this operation. The natural numbers together with the base-b digital sum thus form an abelian group; this group is isomorphic to the direct sum of a countable number of copies of Z/bZ.
Integers
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https://en.wikipedia.org/wiki/Noise%20print
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A noise print is part of a technique used in noise reduction. A noise print is commonly used in audio mastering to help reduce the effects of unwanted noise from a piece of audio. In this case, the noise print would be a recording of the ambient noise in the room, which is then used in spectral subtraction to set multiple expanders, effectively gating out those frequencies whilst the signal level in that band is lower than that in the noise print. Many plugins for studio software can be used to apply noise reduction in this way.
Noise reduction usually results in unwanted artifacts, sometimes referred to as "twittering" or "birdies". Different algorithms for noise reduction control these artifacts with varying levels of success.
See also
Dark frame – analogous technique in image noise reduction
Audio engineering
Noise
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https://en.wikipedia.org/wiki/Secure%20Digital%20Container
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Secure Digital Container (SDC) is a compressed, encrypted executable file type that is made and used by the e-academy License Management System (ELMS) for secure downloads of primarily academic software. After being downloaded, it is decrypted and the software is extracted. The SDC file is created by e-academy for distribution of academic software purchased or freely downloaded by its academic user base. It cannot be opened without the Secure Delivery Client.
The Secure delivery client requests permission from ELMS to download. If ELMS denied the request, the download does not proceed. There is also a limited number of downloads a customer could use. When download count hits zero, a customer would be unable to download more copies of the software.
Older SDC files have weak protection and can be unpacked with the UnpackSDC 1.1 tool.
Recently related SDX files have been introduced. They are metadata for Secure Download Manager, which downloads either normal EXE/MSI files or encrypted SDC files and automatically decrypts them.
See also
DreamSpark
MSDNAA
References
Further reading
Entrepreneur, March 21, 2013, “What You Need to Know About Digital Wallets”
Electronic Frontier Foundation ”Digital Rights Management”
PRWeb, May 1, 2007, “New Digital Distribution Technology Delivers A MySpace Riot”
Computer file formats
Digital rights management
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https://en.wikipedia.org/wiki/Combat%20information%20center
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A combat information center (CIC) or action information centre (AIC) is a room in a warship or AWACS aircraft that functions as a tactical center and provides processed information for command and control of the near battlespace or area of operations. Within other military commands, rooms serving similar functions are known as command centers.
Regardless of the vessel or command locus, each CIC organizes and processes information into a form more convenient and usable by the commander in authority. Each CIC funnels communications and data received over multiple channels, which is then organized, evaluated, weighted and arranged to provide ordered timely information flow to the battle command staff under the control of the CIC officer and his deputies.
Overview
CICs are widely depicted in film and television treatments, frequently with large maps, numerous computer consoles and radar and sonar repeater displays or consoles, as well as the almost ubiquitous grease-pencil annotated polar plot on an edge-lighted transparent plotting board. At the time the CIC concept was born, the projected map-like polar display (PPI scopes) with the ship at the center was making its way into radar displays displacing the A-scope which was simply a time-delayed blip showing a range on the cathode ray tube display of an oscilloscope.
Such polar plots are used routinely in navigation and military action management to display time-stamped range and bearing information to the CIC decision makers. A single 'mark' (range and bearing datum) bears little actionable decision-making information by itself. A succession of such data tells much more, including whether the contact is closing or opening in range, an idea of its speed and direction (these are calculable, even from bearings-only data, given sufficient observations and knowledge of tactics), the relation to other contacts and their ranges and behaviors. Harvesting such data sets from the polar plots and computers (Common to sonar, ra
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https://en.wikipedia.org/wiki/Hosohedron
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In spherical geometry, an -gonal hosohedron is a tessellation of lunes on a spherical surface, such that each lune shares the same two polar opposite vertices.
A regular -gonal hosohedron has Schläfli symbol with each spherical lune having internal angle radians ( degrees).
Hosohedra as regular polyhedra
For a regular polyhedron whose Schläfli symbol is {m, n}, the number of polygonal faces is :
The Platonic solids known to antiquity are the only integer solutions for m ≥ 3 and n ≥ 3. The restriction m ≥ 3 enforces that the polygonal faces must have at least three sides.
When considering polyhedra as a spherical tiling, this restriction may be relaxed, since digons (2-gons) can be represented as spherical lunes, having non-zero area.
Allowing m = 2 makes
and admits a new infinite class of regular polyhedra, which are the hosohedra. On a spherical surface, the polyhedron {2, n} is represented as n abutting lunes, with interior angles of . All these spherical lunes share two common vertices.
Kaleidoscopic symmetry
The digonal spherical lune faces of a -hosohedron, , represent the fundamental domains of dihedral symmetry in three dimensions: the cyclic symmetry , , , order . The reflection domains can be shown by alternately colored lunes as mirror images.
Bisecting each lune into two spherical triangles creates an -gonal bipyramid, which represents the dihedral symmetry , order .
Relationship with the Steinmetz solid
The tetragonal hosohedron is topologically equivalent to the bicylinder Steinmetz solid, the intersection of two cylinders at right-angles.
Derivative polyhedra
The dual of the n-gonal hosohedron {2, n} is the n-gonal dihedron, {n, 2}. The polyhedron {2,2} is self-dual, and is both a hosohedron and a dihedron.
A hosohedron may be modified in the same manner as the other polyhedra to produce a truncated variation. The truncated n-gonal hosohedron is the n-gonal prism.
Apeirogonal hosohedron
In the limit, the hosohedron becomes an ape
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https://en.wikipedia.org/wiki/Haplogroup
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A haplotype is a group of alleles in an organism that are inherited together from a single parent, and a haplogroup (haploid from the , haploûs, "onefold, simple" and ) is a group of similar haplotypes that share a common ancestor with a single-nucleotide polymorphism mutation. More specifically, a haplotype is a combination of alleles at different chromosomal regions that are closely linked and that tend to be inherited together. As a haplogroup consists of similar haplotypes, it is usually possible to predict a haplogroup from haplotypes. Haplogroups pertain to a single line of descent. As such, membership of a haplogroup, by any individual, relies on a relatively small proportion of the genetic material possessed by that individual.
Each haplogroup originates from, and remains part of, a preceding single haplogroup (or paragroup). As such, any related group of haplogroups may be precisely modelled as a nested hierarchy, in which each set (haplogroup) is also a subset of a single broader set (as opposed, that is, to biparental models, such as human family trees).
Haplogroups are normally identified by an initial letter of the alphabet, and refinements consist of additional number and letter combinations, such as (for example) . The alphabetical nomenclature was published in 2002 by the Y Chromosome Consortium.
In human genetics, the haplogroups most commonly studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups, each of which can be used to define genetic populations. Y-DNA is passed solely along the patrilineal line, from father to son, while mtDNA is passed down the matrilineal line, from mother to offspring of both sexes. Neither recombines, and thus Y-DNA and mtDNA change only by chance mutation at each generation with no intermixture between parents' genetic material.
Haplogroup formation
Mitochondria are small organelles that lie in the cytoplasm of eukaryotic cells, such as those of humans. Their primary function is to
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https://en.wikipedia.org/wiki/CB%20Simulator
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CompuServe CB Simulator was the first dedicated online chat service that was widely available to the public. It was developed by a CompuServe executive, Alexander "Sandy" Trevor, and released by CompuServe on February 21, 1980, as the first public, commercial multi-user chat program.
At that time, most people were familiar with citizens band radio, often abbreviated as CB radio, but multi-user chat and instant messaging were largely unknown. CompuServe CB used the CB radio paradigm to help users understand the new concept. Like CB radio, it had 40 "channels" and commands like "tune", "squelch", and "monitor". CompuServe CB quickly became the largest single product on CompuServe despite virtually no marketing. When 40 channels was not enough, additional "bands" were added, such as the "Adult" band.
The first online wedding occurred on CompuServe CB, and worldwide fans organized events to meet in the "real world" people they had met in CB. Compuserve's CBIG (CB Interest Group) Sysop Chris Dunn (ChrisDos) met his wife Pamela (Zebra3) there in the early 1980s, eventually being featured on the Phil Donahue Show. Later, enhancements to CompuServe CB were made to enable multiplayer games, digital pictures, multimedia, and large conferences. For example, Mick Jagger of the Rolling Stones held the first online multimedia conference using CompuServe CB from London on December 7, 1995.
One of the first online weddings occurred between *MilesTeg* and *Cinderella* on May 4, 1991. While the couple said their vows at the Silver Bells Wedding Chapel in Las Vegas, *TennesseeBunny* was dialed in with a laptop computer and a 2,400-bit-per-second modem and broadcast the event play by play. Later the couple celebrated at the "reception" during the Vegas CB Bash at the Palace Station Hotel. The wedding was attended by 20+ CB regulars in person and over 50 virtual guests online. The couple were still married as of 2019.
The CompuServe CB Simulator was also the setting for The Strange
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https://en.wikipedia.org/wiki/Synonymous%20substitution
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A synonymous substitution (often called a silent substitution though they are not always silent) is the evolutionary substitution of one base for another in an exon of a gene coding for a protein, such that the produced amino acid sequence is not modified. This is possible because the genetic code is "degenerate", meaning that some amino acids are coded for by more than one three-base-pair codon; since some of the codons for a given amino acid differ by just one base pair from others coding for the same amino acid, a mutation that replaces the "normal" base by one of the alternatives will result in incorporation of the same amino acid into the growing polypeptide chain when the gene is translated. Synonymous substitutions and mutations affecting noncoding DNA are often considered silent mutations; however, it is not always the case that the mutation is silent.
Since there are 22 codes for 64 codons, roughly we should expect a random substitution to be synonymous with probability about 22/64 = 34%. The actual value is around 20%.
A synonymous mutation can affect transcription, splicing, mRNA transport, and translation, any of which could alter the resulting phenotype, rendering the synonymous mutation non-silent. The substrate specificity of the tRNA to the rare codon can affect the timing of translation, and in turn the co-translational folding of the protein. This is reflected in the codon usage bias that is observed in many species. A nonsynonymous substitution results in a change in amino acid that may be arbitrarily further classified as conservative (a change to an amino acid with similar physiochemical properties), semi-conservative (e.g. negatively to positively charged amino acid), or radical (vastly different amino acid).
Degeneracy of the genetic code
Protein translation involves a set of twenty amino acids. Each of these amino acids is coded for by a sequence of three DNA base pairs called a codon. Because there are 64 possible codons, but only 20-22
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https://en.wikipedia.org/wiki/Polydextrose
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Polydextrose is a synthetic polymer of glucose. It is a food ingredient classified as soluble fiber by the US FDA as well as Health Canada, . It is frequently used to increase the dietary fiber content of food, to replace sugar, and to reduce calories and fat content. It is a multi-purpose food ingredient synthesized from dextrose (glucose), plus about 10 percent sorbitol and 1 percent citric acid. Its E number is E1200. The FDA approved it in 1981.
It is 0.1 times as sweet as sugar.
History
Commercial manufacture of edible polydextrose originated with a process developed by Hans H. Rennhard of Pfizer, Inc. Rennhard began investigating the potential of polysaccharides as low-calorie replacements for sugar, fat, flour, and starch. In 1965, he created polydextrose, a polymer of dextrose, produced from the naturally occurring components: glucose, sorbitol, and citric acid.
Commercial uses
Polydextrose is commonly used as a replacement for sugar, starch, and fat in commercial beverages, cakes, candies, dessert mixes, breakfast cereals, gelatins, frozen desserts, puddings, and salad dressings. Polydextrose is frequently used as an ingredient in low-carb, sugar-free, and diabetic cooking recipes. It is also used as a humectant, stabiliser, and thickening agent.
Polydextrose is a form of soluble fiber and has shown healthful prebiotic benefits when tested in animals. It contains only 1 kcal per gram and, therefore, is able to help reduce calories.
However, polydextrose is not universally well tolerated. Doses as low as 10 g cause significantly more intestinal gas and flatulence than fermentation resistant psyllium.
References
Food additives
Edible thickening agents
Polysaccharides
E-number additives
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https://en.wikipedia.org/wiki/Ssh-agent
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Secure Shell (SSH) is a protocol allowing secure remote login to a computer on a network using public-key cryptography. SSH client programs (such as ssh from OpenSSH) typically run for the duration of a remote login session and are configured to look for the user's private key in a file in the user's home directory (e.g., .ssh/id_rsa). For added security (for instance, against an attacker that can read any file on the local filesystem), it is common to store the private key in an encrypted form, where the encryption key is computed from a passphrase that the user has memorized. Because typing the passphrase can be tedious, many users would prefer to enter it just once per local login session. The most secure place to store the unencrypted key is in program memory, and in Unix-like operating systems, memory is normally associated with a process. A normal SSH client process cannot be used to store the unencrypted key because SSH client processes only last the duration of a remote login session. Therefore, users run a program called ssh-agent that runs beyond the duration of a local login session, stores unencrypted keys in memory, and communicates with SSH clients using a Unix domain socket.
Security issues
ssh-agent creates a socket and then checks the connections from ssh. Everyone who is able to connect to this socket also has access to the ssh-agent. The permissions are set as in a usual Linux or Unix system. When the agent starts, it creates a new directory in /tmp with restrictive permissions. The socket is located in this directory.
There is a procedure that may prevent malware from using the ssh-agent socket. If the ssh-add -c option is set when the keys are imported into the ssh-agent, then the agent requests a confirmation from the user using the program specified by the SSH_ASKPASS environment variable, whenever ssh tries to connect.
Ssh-agents can be "forwarded" onto a server you connect to, making their keys available there as well, for other con
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https://en.wikipedia.org/wiki/ClickOnce
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ClickOnce is a component of Microsoft .NET Framework 2.0 and later, and supports deploying applications made with Windows Forms or Windows Presentation Foundation. It is similar to Java Web Start for the Java Platform or Zero Install for Linux.
Description
The core principle of ClickOnce is to ease the deployment of Windows applications. In addition, ClickOnce aims to solve three other problems with conventional deployment models: the difficulty in updating a deployed application, the impact of an application on the user's computer, and the need for administrator permissions to install applications.
ClickOnce-deployed applications are considered "low impact", in that they are installed per user, not per machine. Administrator privileges are not required to install these applications. Each ClickOnce application is isolated from the others. This means one ClickOnce application is not able to "break" another. ClickOnce employs Code Access Security (CAS) to prevent system functions being called by a ClickOnce application from the web, ensuring the security of data and the client system in general.
Applications
The ClickOnce model supports both installed applications (akin to conventional Windows applications with Start Menu integration) and online applications (browser-hosted applications that are not installed, only run and cached). ClickOnce applications can be deployed to a computer from an internet location, a network share, or a local file location such as a CD-ROM.
The ClickOnce deployment technology has been integrated into Visual Studio 2005 and later. It is also natively supported by MSBuild, Microsoft's build management technology.
Manifests
A ClickOnce deployment is controlled through the use of two XML manifest files: a deployment manifest and an application manifest. The manifests are in the same XML format as the side-by-side assembly implementation. The deployment manifest (*.application file) describes the deployment model: the current version, upda
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https://en.wikipedia.org/wiki/ECall
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eCall (an abbreviation of "emergency call") is an initiative by the European Union, intended to bring rapid assistance to motorists involved in a collision anywhere within the European Union. The aim is for all new cars to incorporate a system that automatically contacts the emergency services in the event of a serious accident, sending location and sensor information. eCall was made mandatory in all new cars approved for manufacture within the European Union as of April 2018.
History
The concept of eCall was presented in 1999 by European civil servant Luc Tytgat, during the launch of the European Commission's Galileo project. One year earlier, 170 experts met in Brussels, invited by the Commission, to analyse the European dependence on the American GPS system, but also to gather civilian applications propositions.
In 2001, the project was first presented as a European calling system, in the context of the German youth science competition Jugend forscht. In 2007, the project was postponed. In 2011, the project was pushed again by the European Commission. In the summer of 2013, the project was adopted and was scheduled to be completed by 1 October 2015.
On 6 September 2013, trade associations operating in the automotive after market (like AIRC, CLEPA, FIA, FIGEAFA) welcomed the European Commission's eCall initiative and fully support the Europe-wide mandatory introduction of eCall by 2015 in all new type-approved cars and light commercial vehicles. AIRC (Association des Reparateurs en Carrosserie) General Secretary Karel Bukholczer said that eCall represents an important initiative to reduce fatalities and the severity of injuries on Europe's roads.
Slovenia introduced eCall in December 2015. Italy deployed a pilot program in selected regions in May 2017, and Sweden adopted eCall in October 2017.
Since 2018, eCall is part of an UNECE effort to standardize the devices with the UNECE Regulation 144 related to accident emergency call components (AECC), accident em
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https://en.wikipedia.org/wiki/Classification%20of%20electromagnetic%20fields
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In differential geometry and theoretical physics, the classification of electromagnetic fields is a pointwise classification of bivectors at each point of a Lorentzian manifold. It is used in the study of solutions of Maxwell's equations and has applications in Einstein's theory of relativity.
The classification theorem
The electromagnetic field at a point p (i.e. an event) of a Lorentzian spacetime is represented by a real bivector defined over the tangent space at p.
The tangent space at p is isometric as a real inner product space to E1,3. That is, it has the same notion of vector magnitude and angle as Minkowski spacetime. To simplify the notation, we will assume the spacetime is Minkowski spacetime. This tends to blur the distinction between the tangent space at p and the underlying manifold; fortunately, nothing is lost by this specialization, for reasons we discuss as the end of the article.
The classification theorem for electromagnetic fields characterizes the bivector F in relation to the Lorentzian metric by defining and examining the so-called "principal null directions". Let us explain this.
The bivector Fab yields a skew-symmetric linear operator defined by lowering one index with the metric. It acts on the tangent space at p by . We will use the symbol F to denote either the bivector or the operator, according to context.
We mention a dichotomy drawn from exterior algebra. A bivector that can be written as , where v, w are linearly independent, is called simple. Any nonzero bivector over a 4-dimensional vector space either is simple, or can be written as , where v, w, x, and y are linearly independent; the two cases are mutually exclusive. Stated like this, the dichotomy makes no reference to the metric η, only to exterior algebra. But it is easily seen that the associated skew-symmetric linear operator Fab has rank 2 in the former case and rank 4 in the latter case.
To state the classification theorem, we consider the eigenvalue problem fo
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https://en.wikipedia.org/wiki/Winter%20Games
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Winter Games is a sports video game developed by Epyx (and released in Europe by U.S. Gold), based on sports featured in the Winter Olympic Games.
A snow-and-ice themed follow-up to the highly successful Summer Games, Winter Games was released in 1985 for the Commodore 64 and later ported to several popular home computers and video game consoles of the 1980s.
The game was presented as a virtual multi-sport carnival called the "Epyx Winter Games" (there was no official IOC licensing in place) with up to 8 players each choosing a country to represent, and then taking turns competing in various events to try for a medal.
Events
The events available vary slightly depending on the platform, but include some or all of the following:
Slalom skiing
Ski jumping
Biathlon
Bobsled
Figure skating
Speed skating
Luge
Freestyle skiing; more precisely, the aerial skiing discipline, called "Hot Dog Aerials" in the game
Free skating
The game allows players to compete in all of the events sequentially, choose a few events, choose just one event, or practice an event.
Ports
Winter Games was ported to the Amiga, Apple II, Atari ST, Apple Macintosh, Apple IIGS, Amstrad CPC, ZX Spectrum, and IBM PC computer platforms, and to the Atari 2600, Atari 7800, Nintendo Entertainment System, and the Family Computer Disk System video game consoles. In 2004, it was featured as one of the games on the C64 Direct-to-TV. A Virtual Console version was released in Europe on February 20, 2009.
Reception
Winter Games was Epyx's best-selling Commodore game as of late 1987. Its sales had surpassed 250,000 copies by November 1989.
Info rated Winter Games four-plus stars out of five, stating that each event was good enough to be sold separately, and concluding that it was "sports simulation at its best!". In 1985, Zzap!64 gave 94% for the game calling it "another classic sport simulation from Epyx". Lemon64 website users have given average vote of 8.6 which places the game on top 20 list on the
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https://en.wikipedia.org/wiki/AS2
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AS2 (Applicability Statement 2) is a specification on how to transport structured business-to-business data securely and reliably over the Internet. Security is achieved by using digital certificates and encryption.
Background
AS2 was created in 2002 by the IETF to replace AS1, which they created in the early 1990s.
The adoption of AS2 grew rapidly throughout the early 2000s because major players in the retail and fast-moving consumer goods industries championed AS2. Walmart was the first major retailer to require its suppliers to use the AS2 protocol instead of relying on dial-up modems for ordering goods. Amazon, Target, Lowe's, Bed, Bath, & Beyond and thousands of others followed suit. Many other industries use the AS2 protocol, including healthcare, as AS2 meets legal HIPAA requirements.
In some cases, AS2 is a way to bypass expensive value-added networks previously used for data interchange.
Technical overview
AS2 is specified in RFC 4130, and is based on HTTP and S/MIME. It was the second AS protocol developed and uses the same signing, encryption and MDN (as defined by RFC3798) conventions used in the original AS1 protocol introduced in the late 1990s by IETF . In other words:
Files are encoded as "attachments" in a standardized S/MIME message (an AS2 message). AS2 does not specify the contents of the files. Usually, the file contents are in a standardized format that is separately agreed upon, such as XML or EDIFACT.
AS2 messages are always sent using the HTTP or HTTPS protocol (Secure Sockets Layer — also known as SSL — is implied by HTTPS) and usually use the "POST" method (use of "GET" is rare).
Messages can be signed, but do not have to be.
Messages can be encrypted, but do not have to be.
Messages may request a Message Disposition Notification (MDN) back if all went well, but do not have to request such a message.
If the original AS2 message requested an MDN:
Upon the receipt of the message and its successful decryption or signature valida
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https://en.wikipedia.org/wiki/Lunar%20effect
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The lunar effect is a purported correlation between specific stages of the roughly 29.5-day lunar cycle and behavior and physiological changes in living beings on Earth, including humans. A considerable number of studies have examined the effect on humans. By the late 1980s, there were at least 40 published studies on the purported lunar-lunacy connection, and at least 20 published studies on the purported lunar-birthrate connection. Literature reviews and metanalyses have found no correlation between the lunar cycle and human biology or behavior. In cases such as the approximately monthly cycle of menstruation in humans (but not other mammals), the coincidence in timing reflects no known lunar influence. The widespread and persistent beliefs about the influence of the Moon may depend on illusory correlation – the perception of an association that does not in fact exist.
In a number of marine animals, there is stronger evidence for the effects of lunar cycles. Observed effects relating to reproductive synchrony may depend on external cues relating to the presence or amount of moonlight. Corals contain light-sensitive cryptochromes, proteins that are sensitive to different levels of light. Coral species such as Dipsastraea speciosa tend to synchronize spawning in the evening or night, around the last quarter moon of the lunar cycle. In Dipsastraea speciosa, a period of darkness between sunset and moonrise appears to be a trigger for synchronized spawning. Another marine animal, the bristle worm Platynereis dumerilii, spawns a few days after a full moon. It contains a protein with light-absorbing flavin structures that differentially detect moonlight and sunlight. It is used as a model for studying the biological mechanisms of marine lunar cycles.
Contexts
Claims of a lunar connection have appeared in the following contexts:
Fertility
It is widely believed that the Moon has a relationship with fertility due to the corresponding human menstrual cycle, which
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https://en.wikipedia.org/wiki/Euler%20function
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In mathematics, the Euler function is given by
Named after Leonhard Euler, it is a model example of a q-series and provides the prototypical example of a relation between combinatorics and complex analysis.
Properties
The coefficient in the formal power series expansion for gives the number of partitions of k. That is,
where is the partition function.
The Euler identity, also known as the Pentagonal number theorem, is
is a pentagonal number.
The Euler function is related to the Dedekind eta function as
The Euler function may be expressed as a q-Pochhammer symbol:
The logarithm of the Euler function is the sum of the logarithms in the product expression, each of which may be expanded about q = 0, yielding
which is a Lambert series with coefficients -1/n. The logarithm of the Euler function may therefore be expressed as
where -[1/1, 3/2, 4/3, 7/4, 6/5, 12/6, 8/7, 15/8, 13/9, 18/10, ...] (see OEIS A000203)
On account of the identity , where is the sum-of-divisors function, this may also be written as
.
Also if and , then
Special values
The next identities come from Ramanujan's Notebooks:
Using the Pentagonal number theorem, exchanging sum and integral, and then invoking complex-analytic methods, one derives
References
Number theory
Q-analogs
Leonhard Euler
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https://en.wikipedia.org/wiki/Anosov%20diffeomorphism
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In mathematics, more particularly in the fields of dynamical systems and geometric topology, an Anosov map on a manifold M is a certain type of mapping, from M to itself, with rather clearly marked local directions of "expansion" and "contraction". Anosov systems are a special case of Axiom A systems.
Anosov diffeomorphisms were introduced by Dmitri Victorovich Anosov, who proved that their behaviour was in an appropriate sense generic (when they exist at all).
Overview
Three closely related definitions must be distinguished:
If a differentiable map f on M has a hyperbolic structure on the tangent bundle, then it is called an Anosov map. Examples include the Bernoulli map, and Arnold's cat map.
If the map is a diffeomorphism, then it is called an Anosov diffeomorphism.
If a flow on a manifold splits the tangent bundle into three invariant subbundles, with one subbundle that is exponentially contracting, and one that is exponentially expanding, and a third, non-expanding, non-contracting one-dimensional sub-bundle (spanned by the flow direction), then the flow is called an Anosov flow.
A classical example of Anosov diffeomorphism is the Arnold's cat map.
Anosov proved that Anosov diffeomorphisms are structurally stable and form an open subset of mappings (flows) with the C1 topology.
Not every manifold admits an Anosov diffeomorphism; for example, there are no such diffeomorphisms on the sphere . The simplest examples of compact manifolds admitting them are the tori: they admit the so-called linear Anosov diffeomorphisms, which are isomorphisms having no eigenvalue of modulus 1. It was proved that any other Anosov diffeomorphism on a torus is topologically conjugate to one of this kind.
The problem of classifying manifolds that admit Anosov diffeomorphisms turned out to be very difficult, and still has no answer for dimension over 3. The only known examples are infranilmanifolds, and it is conjectured that they are the only ones.
A sufficient condition f
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https://en.wikipedia.org/wiki/Dmitri%20Anosov
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Dmitri Victorovich Anosov (; November 30, 1936 – August 7, 2014) was a Russian mathematician active during the Soviet Union, he is best known for his contributions to dynamical systems theory.
He was a full member of the Russian Academy of Sciences and a laureate of the USSR State Prize (1976). He was a student of Lev Pontryagin. In 2014, he died at the age of 77.
See also
Anosov diffeomorphism
Anosov map
Pseudo-Anosov map
References
External links
Author profile in the database zbMATH
1936 births
2014 deaths
20th-century Russian mathematicians
21st-century Russian mathematicians
Soviet mathematicians
Anosov, Dmitri Victorovich
Recipients of the USSR State Prize
Dynamical systems theorists
Burials in Troyekurovskoye Cemetery
Academic staff of Moscow State University
Russian scientists
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https://en.wikipedia.org/wiki/PageStream
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PageStream (originally Publishing Partner) is a desktop publishing software package by Grasshopper LLC (United States) currently available for a variety of operating systems including Windows, Linux, and macOS. The software was originally released under the name Publishing Partner for the Atari ST in 1986 by Soft-Logic Publishing Corporation.
Publishing Partner 1.5 was released for the Atari ST and Commodore Amiga platform in 1989. Version 1.8 followed in 1990 with an improved user interface and manual. Publishing Partner Professional 2.0, renamed to PageStream 2.0, was released for the Amiga in 1990 and Atari ST in 1991. This version added support for PostScript fonts and for the Amiga, AGFA Compugraphic Intellifont support.
PageStream 2.2 for Amiga and Atari ST was released in 1992 with support for the HotLinks Editions publish-subscribe system which was bundled with the PageLiner text editor and BME bitmap image editor.
PageStream 3.0 for Amiga was released in 1994. The application was entirely rewritten with a new user interface and many new features including colour separations, table of contents, index, nested chapters, Bézier curves, horizontal and vertical multi-page spreads, drop caps, hanging punctuation, Pantone colors, auto-kerning, auto-hyphenation, and ARexx scripting support.
In 1996 PageStream 3.1 and 3.2 were released for Amiga and a pre-release of PageStream was made available for Macintosh System 7. Various extensions were released for PageStream including TextFX (vector text warp), Borders (vector borders for rectangles), and Gary's Effects (image processing filters).
PageStream 3.3 was released for Amiga and Macintosh in 1997 with new fly-out tools for shapes, grids, and notes, as well as RTF export, a character panel, and improved chapter support. The Macintosh version included support for AppleScript.
PageStream 4.0 was released in 1999 with added support for Windows and Linux support was added in 2004. According to the official website,
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https://en.wikipedia.org/wiki/Link%20adaptation
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Link adaptation, comprising adaptive coding and modulation (ACM) and others (such as Power Control), is a term used in wireless communications to denote the matching of the modulation, coding and other signal and protocol parameters to the conditions on the radio link (e.g. the pathloss, the interference due to signals coming from other transmitters, the sensitivity of the receiver, the available transmitter power margin, etc.). For example, WiMAX uses a rate adaptation algorithm that adapts the modulation and coding scheme (MCS) according to the quality of the radio channel, and thus the bit rate and robustness of data transmission. The process of link adaptation is a dynamic one and the signal and protocol parameters change as the radio link conditions change—for example in High-Speed Downlink Packet Access (HSDPA) in Universal Mobile Telecommunications System (UMTS) this can take place every 2 ms.
Adaptive modulation systems invariably require some channel state information at the transmitter. This could be acquired in time-division duplex systems by assuming the channel from the transmitter to the receiver is approximately the same as the channel from the receiver to the transmitter. Alternatively, the channel knowledge can also be directly measured at the receiver, and fed back to the transmitter. Adaptive modulation systems improve rate of transmission, and/or bit error rates, by exploiting the channel state information that is present at the transmitter. Especially over fading channels which model wireless propagation environments, adaptive modulation systems exhibit great performance enhancements compared to systems that do not exploit channel knowledge at the transmitter.
Example
In HSDPA link adaptation is performed by:
Choice of modulation type—the link can employ QPSK for noisy channels and 16QAM for clearer channels. The former is more robust and can tolerate higher levels of interference but has lower spectral efficiency, which means it may transmi
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https://en.wikipedia.org/wiki/Topping%20out
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In building construction, topping out (sometimes referred to as topping off) is a builders' rite traditionally held when the last beam (or its equivalent) is placed atop a structure during its construction. Nowadays, the ceremony is often parlayed into a media event for public relations purposes. It has since come to mean more generally finishing the structure of the building, whether there is a ceremony or not. It is also commonly used to determine the amount of wind on the top of the structure.
History
The practice of "topping out" a new building can be traced to the ancient Scandinavian religious rite of placing a tree atop a new building to appease the tree-dwelling spirits displaced in its construction. The tradition also served a functional purpose: a pine tree was used, and after the needles had fallen off the tree, the builders knew the wood frame below had cured/dried out so they could enclose the building. Long an important component of timber frame building, it migrated initially to England and Northern Europe, thence to the Americas.
A tree or leafy branch is placed on the topmost wood or iron beam, often with flags and streamers tied to it. A toast is usually drunk and sometimes workers are treated to a meal. In masonry construction the rite celebrates the bedding of the last block or brick.
In some cases a topping out event is held at an intermediate point, such as when the roof is dried-in, which means the roof can provide at least semi-permanent protection from the elements.
The practice remains common in the United Kingdom and assorted Commonwealth countries such as Australia and Canada, as well as Germany, Austria, Slovenia, Iceland, Chile, Czech Republic, Slovakia, Poland, Hungary and the Baltic States. In the United States the last beam of a skyscraper is often painted white and signed by all the workers involved. In New Zealand, completion of the roof to a water-proof state is celebrated through a "roof shout", where workers are treated t
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https://en.wikipedia.org/wiki/European%20Network%20for%20Training%20and%20Research%20in%20Electrical%20Engineering
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Exchange programs for Electrical Engineering students between 18 universities in Europe. It is also known as Entree. Their members are:
Chalmers Lindholmen University College (Sweden)
University of Aalborg (Denmark)
Heriot-Watt University (United Kingdom)
Brunel University (United Kingdom)
Delft University of Technology (Netherlands)
Université libre de Bruxelles (Belgium)
Technische Universität Dresden (Germany)
Karlsruhe Institute of Technology (Germany)
École Supérieure d'Ingénieurs en Électronique et Électrotechnique Paris (France)
École Supérieure d'Ingénieurs en Électronique et Électrotechnique Amiens (France)
École polytechnique fédérale de Lausanne (Switzerland)
Brno University of Technology (Czech Republic)
National Technical University of Athens (Greece)
Politecnico di Milano (Italy)
Pontifical Comillas University of Madrid (Spain)
University of Valladolid (Spain)
Institut Méditerranéen de Technologie (France)
Politecnico di Torino (Italy)
References
College and university associations and consortia in Europe
Electrical engineering organizations
Engineering university associations and consortia
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https://en.wikipedia.org/wiki/Elastic%20recoil%20detection
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Elastic recoil detection analysis (ERDA), also referred to as forward recoil scattering (or, contextually, spectrometry), is an ion beam analysis technique in materials science to obtain elemental concentration depth profiles in thin films. This technique is known by several different names. These names are listed below. In the technique of ERDA, an energetic ion beam is directed at a sample to be characterized and (as in Rutherford backscattering) there is an elastic nuclear interaction between the ions of beam and the atoms of the target sample. Such interactions are commonly of Coulomb nature. Depending on the kinetics of the ions, cross section area, and the loss of energy of the ions in the matter, ERDA helps determine the quantification of the elemental analysis. It also provides information about the depth profile of the sample.
The energy of incident energetic ions can vary from 2 MeV to 200 MeV, depending on the studied sample. The energy of the beam should be enough to kick out (“recoil”) the atoms of the sample. Thus, ERD usually employs appropriate source and detectors to detect recoiled atoms.
ERDA setup is large, expensive and difficult to operate. Therefore, although it is commercially available, it is relatively uncommon in materials characterization. The angle of incidence that an ion beam makes with the sample must also be taken into account for correct analysis of the sample. This is because, depending on this angle, the recoiled atoms will be collected.
ERDA has been used since the mid-1970s. It has similar theory to Rutherford backscattering spectrometry (RBS), but there are minor differences in the set-up of the experiment. In case of RBS, the detector is placed in the back of the sample whereas in ERDA, the detector is placed in the front.
Characteristics of ERDA
The main characteristics of ERDA are listed below.
A variety of elements can be analyzed simultaneously as long as the atomic number of recoiled ion is smaller than the atomic n
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https://en.wikipedia.org/wiki/Degrees%20of%20freedom%20%28mechanics%29
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In physics, the degrees of freedom (DOF) of a mechanical system is the number of independent parameters that define its configuration or state. It is important in the analysis of systems of bodies in mechanical engineering, structural engineering, aerospace engineering, robotics, and other fields.
The position of a single railcar (engine) moving along a track has one degree of freedom because the position of the car is defined by the distance along the track. A train of rigid cars connected by hinges to an engine still has only one degree of freedom because the positions of the cars behind the engine are constrained by the shape of the track.
An automobile with highly stiff suspension can be considered to be a rigid body traveling on a plane (a flat, two-dimensional space). This body has three independent degrees of freedom consisting of two components of translation and one angle of rotation. Skidding or drifting is a good example of an automobile's three independent degrees of freedom.
The position and orientation of a rigid body in space is defined by three components of translation and three components of rotation, which means that it has six degrees of freedom.
The exact constraint mechanical design method manages the degrees of freedom to neither underconstrain nor overconstrain a device.
Motions and dimensions
The position of an n-dimensional rigid body is defined by the rigid transformation, [T] = [A, d], where d is an n-dimensional translation and A is an n × n rotation matrix, which has n translational degrees of freedom and n(n − 1)/2 rotational degrees of freedom. The number of rotational degrees of freedom comes from the dimension of the rotation group SO(n).
A non-rigid or deformable body may be thought of as a collection of many minute particles (infinite number of DOFs), this is often approximated by a finite DOF system. When motion involving large displacements is the main objective of study (e.g. for analyzing the motion of satellites),
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https://en.wikipedia.org/wiki/Cytokine%20storm
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A cytokine storm, also called hypercytokinemia, is a physiological reaction in humans and other animals in which the innate immune system causes an uncontrolled and excessive release of pro-inflammatory signaling molecules called cytokines. Normally, cytokines are part of the body's immune response to infection, but their sudden release in large quantities may cause multisystem organ failure and death.
Cytokine storms may be caused by a number of infectious and non-infectious etiologies, especially viral respiratory infections such as H1N1 influenza, H5N1 influenza, SARS-CoV-1, SARS-CoV-2, Influenza B, and Parainfluenza virus. Other causative agents include the Epstein-Barr virus, cytomegalovirus, group A streptococcus, and non-infectious conditions such as graft-versus-host disease. The viruses can invade lung epithelial cells and alveolar macrophages to produce viral nucleic acid, which stimulates the infected cells to release cytokines and chemokines, activating macrophages, dendritic cells, and others.
Cytokine storm syndrome is a diverse set of conditions that can result in a cytokine storm. Cytokine storm syndromes include familial hemophagocytic lymphohistiocytosis, Epstein-Barr virus–associated hemophagocytic lymphohistiocytosis, systemic or non-systemic juvenile idiopathic arthritis–associated macrophage activation syndrome, NLRC4 macrophage activation syndrome, cytokine release syndrome and sepsis.
Cytokine storms versus cytokine release syndrome
The term "cytokine storm" is often loosely used interchangeably with cytokine release syndrome (CRS) but is more precisely a differentiable syndrome that may represent a severe episode of cytokine release syndrome or a component of another disease entity, such as macrophage activation syndrome. When occurring as a result of a therapy, CRS symptoms may be delayed until days or weeks after treatment. Immediate-onset (fulminant) CRS appears to be a cytokine storm.
Research
Nicotinamide (a form of vitamin B3) is
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https://en.wikipedia.org/wiki/Coronal%20plane
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The coronal plane (also known as the frontal plane) is an anatomical plane that divides the body into dorsal and ventral sections. It is perpendicular to the sagittal and transverse planes.
Details
The coronal plane is an example of a longitudinal plane. For a human, the mid-coronal plane would transect a standing body into two halves (front and back, or anterior and posterior) in an imaginary line that cuts through both shoulders. The description of the coronal plane applies to most animals as well as humans even though humans walk upright and the various planes are usually shown in the vertical orientation.
The sternal plane (planum sternale) is a coronal plane which transects the front of the sternum.
Etymology
The term is derived from Latin corona ('garland, crown'), from Ancient Greek κορώνη (korōnē, 'garland, wreath'). The coronal plane is so called because it lies in the same direction as the coronal suture.
Additional images
See also
Anatomical terms of location
Sagittal plane
Transverse plane
References
External links
Anatomical planes
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https://en.wikipedia.org/wiki/Transverse%20plane
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The transverse plane (also known as the horizontal plane, axial plane and transaxial plane) is an anatomical plane that divides the body into superior and inferior sections. It is perpendicular to the coronal and sagittal planes.
List of clinically relevant anatomical planes
Transverse thoracic plane
Xiphosternal plane (or xiphosternal junction)
Transpyloric plane
Subcostal plane
Umbilical plane (or transumbilical plane)
Supracristal plane
Intertubercular plane (or transtubercular plane)
Interspinous plane
Clinically relevant anatomical planes with associated structures
The transverse thoracic plane
Plane through T4 & T5 vertebral junction and sternal angle of Louis.
Marks the:
Attachment of costal cartilage of rib 2 at the sternal angle;
Aortic arch (beginning and end);
Upper margin of SVC;
Thoracic duct crossing;
Tracheal bifurcation;
Pulmonary trunk bifurcation;
The xiphosternal plane (a.k.a. xiphosternal junction)
Anterior, inferior limit of thoracic cavity;
Marks the:
Superior surface of the liver;
Respiratory diaphragm;
Inferior border of the heart;
The transpyloric plane
Plane located halfway between the jugular notch and the upper border of the symphysis pubis;
Typically located at the lower border of L1;
Cuts through the pylorus and the tips of the ninth costal cartilages;
The subcostal plane
Transverse plane through the inferior border of costal margin;
Typically located at the superior border of L3, or transects L3;
The umbilical plane (or transumbilical plane)
Located at the level of L3/L4 vertebral junction or IV disc;
The supracristal plane
Located at the level of L4;
Marks bifurcation of aorta;
Most superior aspect of iliac crest;
The intertubercular plane (a.k.a. Transtubercular plane)
Located at the level of L5;
Marks origin of IVC;
The interspinous plane
Transverse plane which transverses the anterior superior iliac spines.
Typically located at the level of S1.
See also
Anatomical terms of location
Ho
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