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https://en.wikipedia.org/wiki/KEGG
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KEGG (Kyoto Encyclopedia of Genes and Genomes) is a collection of databases dealing with genomes, biological pathways, diseases, drugs, and chemical substances. KEGG is utilized for bioinformatics research and education, including data analysis in genomics, metagenomics, metabolomics and other omics studies, modeling and simulation in systems biology, and translational research in drug development.
The KEGG database project was initiated in 1995 by Minoru Kanehisa, professor at the Institute for Chemical Research, Kyoto University, under the then ongoing Japanese Human Genome Program. Foreseeing the need for a computerized resource that can be used for biological interpretation of genome sequence data, he started developing the KEGG PATHWAY database. It is a collection of manually drawn KEGG pathway maps representing experimental knowledge on metabolism and various other functions of the cell and the organism. Each pathway map contains a network of molecular interactions and reactions and is designed to link genes in the genome to gene products (mostly proteins) in the pathway. This has enabled the analysis called KEGG pathway mapping, whereby the gene content in the genome is compared with the KEGG PATHWAY database to examine which pathways and associated functions are likely to be encoded in the genome.
According to the developers, KEGG is a "computer representation" of the biological system. It integrates building blocks and wiring diagrams of the system—more specifically, genetic building blocks of genes and proteins, chemical building blocks of small molecules and reactions, and wiring diagrams of molecular interaction and reaction networks. This concept is realized in the following databases of KEGG, which are categorized into systems, genomic, chemical, and health information.
Systems information
PATHWAY: pathway maps for cellular and organismal functions
MODULE: modules or functional units of genes
BRITE: hierarchical classifications of biological ent
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https://en.wikipedia.org/wiki/International%20Conference%20on%20Mobile%20Computing%20and%20Networking
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MobiCom, the International Conference on Mobile Computing and Networking, is a series of annual conferences sponsored by ACM SIGMOBILE dedicated to addressing the challenges in the areas of mobile computing and wireless and mobile networking. Although no rating system for computer networking conferences exists, MobiCom is generally considered to be the best conference in these areas, and it is the fifth highest-impact venue in all of Computer Science. The quality of papers published in this conference is very high. The acceptance rate of MobiCom typically around 10%, meaning that only one tenth of all submitted papers make it through the tough peer review filter.
According to SIGMOBILE, "the MobiCom conference series serves as the premier international forum addressing networks, systems, algorithms, and applications that support the symbiosis of mobile computers and wireless networks. MobiCom is a highly selective conference focusing on all issues in mobile computing and wireless and mobile networking at the link layer and above."
MobiCom Conferences have been held at the following locations:
MobiCom 2020, London, UK, 14-18 September 2020
MobiCom 2019, Los Cabos, Mexico, 21-25 October 2019
MobiCom 2018, New Delhi, India, 29 October-2 November 2018
MobiCom 2017, Snowbird, United States, 16-20 October 2017
MobiCom 2016, New York City, United States, 3–7 October 2016
MobiCom 2015, Paris, France, 7–11 September 2015
MobiCom 2014, Maui, Hawaii, United States, 7–11 September 2014
MobiCom 2013, Miami, Florida, United States, 30 September-4 October 2013
MobiCom 2012, Istanbul, Turkey, 22–26 August 2012
MobiCom 2011, Las Vegas, Nevada, United States, 19–23 September 2011
MobiCom 2010, Chicago, Illinois, United States, 20–24 September 2010
MobiCom 2009, Beijing, China, 20–25 September 2009
MobiCom 2008, San Francisco, California, United States, 13–19 September 2008
MobiCom 2007, Montreal, Quebec, Canada, 9–14 September 2007
MobiCom 2006, Los Angeles, Califo
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https://en.wikipedia.org/wiki/Vaccination%20and%20religion
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Vaccination and religion have interrelations of varying kinds. No major religion prohibits vaccinations, and some consider it an obligation because of the potential to save lives. However, some people cite religious adherence as a basis for opting to forego vaccinating themselves or their children. Many such objections are pretextual: in Australia, anti-vaccinationists founded the Church of Conscious Living, a "fake church", leading to religious exemptions being removed in that country, and one US pastor was reported to offer vaccine exemptions in exchange for online membership of his church.
Historical
The influential Massachusetts preacher Cotton Mather was the first known person to attempt smallpox inoculation on a large scale, inoculating himself and more than two hundred members of his congregation with the help of a local doctor. While his view later became standard, there was a strong negative reaction against him at the time.
Rowland Hill (1744–1833) was a popular English preacher acquainted with Edward Jenner, the pioneer of smallpox vaccination, and he encouraged the vaccination of the congregations he visited or preached to. He published a tract on the subject in 1806, at a time when many medical men refused to sanction it. Later he became a member of the Royal Jennererian Society, which was established when vaccination was accepted in Britain, India, the US, and elsewhere. John C. Lettsom, an eminent Quaker physician of the day wrote to Rowland Hill commenting:
Several Boston clergymen and devout physicians formed a society that opposed vaccination in 1798. Others complained that the practice was dangerous, going so far as to demand that doctors who carried out these procedures be tried for attempted murder.
In 1816 Iceland made the clergy responsible for smallpox vaccination and gave them the responsibility of keeping vaccination records for their parishes; Sweden also had similar practices.
When vaccination was introduced into UK public policy,
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https://en.wikipedia.org/wiki/Fremitus
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Fremitus is a vibration transmitted through the body. In common medical usage, it usually refers to assessment of the lungs by either the vibration intensity felt on the chest wall (tactile fremitus) and/or heard by a stethoscope on the chest wall with certain spoken words (vocal fremitus), although there are several other types.
Types
Vocal fremitus
When a person speaks, the vocal cords create vibrations (vocal fremitus) in the tracheobronchial tree and through the lungs and chest wall, where they can be felt (tactile fremitus). This is usually assessed with the healthcare provider placing the flat of their palms on the chest wall and then asking a patient to repeat a phrase containing low-frequency vowels such as "blue balloons" or "toys for tots" (the original diphthong used was the German word neunundneunzig but the translation to the English 'ninety-nine' was a higher-frequency diphthong and thus not as effective in eliciting fremitus). An increase in tactile fremitus indicates denser or inflamed lung tissue, which can be caused by diseases such as pneumonia. A decrease suggests air or fluid in the pleural spaces or a decrease in lung tissue density, which can be caused by diseases such as chronic obstructive pulmonary disease or asthma.
Pleural fremitus
Pleural fremitus is a palpable vibration of the wall of the thorax caused by friction between the parietal and visceral pleura of the lungs. See pleural friction rub for the auditory analog of this sign.
Dental fremitus
Fremitus appears when teeth move. This can be assessed by feeling and looking at teeth when the mouth is opened and closed.
Periodontal fremitus
Periodontal fremitus occurs in either of the alveolar bones when an individual sustains trauma from occlusion. It is a result of teeth exhibiting at least slight mobility rubbing against the adjacent walls of their sockets, the volume of which has been expanded ever so slightly by inflammatory responses, bone resorption or both. As a test to
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https://en.wikipedia.org/wiki/SCR-584%20radar
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The SCR-584 (short for Set, Complete, Radio # 584) was an automatic-tracking microwave radar developed by the MIT Radiation Laboratory during World War II. It was one of the most advanced ground-based radars of its era, and became one of the primary gun laying radars used worldwide well into the 1950s. A trailer-mounted mobile version was the SCR-784.
In 1937, America's first fire-control radar, the SCR-268 radar, had proven to be insufficiently accurate due in part to its long wavelength. In 1940, Vannevar Bush, heading the National Defense Research Committee, established the "Microwave Committee" (section D-1) and the "Fire Control" division (D-2) to develop a more advanced radar anti-aircraft system in time to assist the British air-defense effort. In September of that year, a British delegation, the Tizard Mission, revealed to US and Canadian researchers that they had developed a magnetron oscillator operating at the top end of the UHF band (10 cm wavelength/3 GHz), allowing greatly increased accuracy. Bush organized the Radiation Laboratory (Rad Lab) at the MIT to develop applications using it. This included a new short-range air-defense radar.
Alfred Lee Loomis, running the Rad Lab, advocated the development of an entirely automatic tracking system controlled by servomechanisms. This greatly eased the task of tracking targets and reduced the manpower needed to do it. They were also able to take advantage of a newly developed microwave switch that allowed them to use a single antenna for broadcast and reception, greatly simplifying the mechanical layout. The resulting design fit into a single trailer, could provide all-sky search and single target tracking, and followed the targets automatically. In close contact with the Rad Lab, Bell Telephone Laboratories was developing an electronic analog gun-director that would be used in conjunction with the radar and servo-actuated 90 mm anti-aircraft guns.
The radar was intended to be introduced in late 1943, but de
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https://en.wikipedia.org/wiki/Deterministic%20pushdown%20automaton
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In automata theory, a deterministic pushdown automaton (DPDA or DPA) is a variation of the pushdown automaton. The class of deterministic pushdown automata accepts the deterministic context-free languages, a proper subset of context-free languages.
Machine transitions are based on the current state and input symbol, and also the current topmost symbol of the stack. Symbols lower in the stack are not visible and have no immediate effect. Machine actions include pushing, popping, or replacing the stack top. A deterministic pushdown automaton has at most one legal transition for the same combination of input symbol, state, and top stack symbol. This is where it differs from the nondeterministic pushdown automaton.
Formal definition
A (not necessarily deterministic) PDA can be defined as a 7-tuple:
where
is a finite set of states
is a finite set of input symbols
is a finite set of stack symbols
is the start state
is the starting stack symbol
, where is the set of accepting, or final, states
is a transition function, where
where is the Kleene star, meaning that is "the set of all finite strings (including the empty string ) of elements of ", denotes the empty string, and is the power set of a set .
M is deterministic if it satisfies both the following conditions:
For any , the set has at most one element.
For any , if , then for every
There are two possible acceptance criteria: acceptance by empty stack and acceptance by final state. The two are not equivalent for the deterministic pushdown automaton (although they are for the non-deterministic pushdown automaton). The languages accepted by empty stack are those languages that are accepted by final state and are prefix-free: no word in the language is the prefix of another word in the language.
The usual acceptance criterion is final state, and it is this acceptance criterion which is used to define the deterministic context-free languages.
Languages recognized
If is a language accepted b
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https://en.wikipedia.org/wiki/Z8%20Encore%21
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The Zilog Z8 Encore! is a microcontroller based on the popular Z8 microcontroller.
The Z8 Encore! offers a wide range of features for use in embedded applications, most notably the use of three DMA channels to read for example from the analog-to-digital converter (ADC).
The Z8 Encore! instruction set is compatible with that of the Z8 but it provides some extensions for use with high-level languages.
The Z8 Encore! features a single-pin debugging interface.
External links
Official site of ZiLOG, Inc.
Z8 Encore! page on Zilog site
Microcontrollers
Zilog microprocessors
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https://en.wikipedia.org/wiki/Hypermobility%20%28joints%29
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Hypermobility, also known as double-jointedness, describes joints that stretch farther than normal. For example, some hypermobile people can bend their thumbs backwards to their wrists and bend their knee joints backwards, put their leg behind the head or perform other contortionist "tricks". It can affect one or more joints throughout the body.
Hypermobile joints are common and occur in about 10 to 25% of the population, but in a minority of people, pain and other symptoms are present. This may be a sign of what is known as joint hypermobility syndrome (JMS) or, more recently, hypermobility spectrum disorder (HSD). Hypermobile joints are a feature of genetic connective tissue disorders such as hypermobility spectrum disorder (HSD) or Ehlers–Danlos syndromes (EDS). Until new diagnostic criteria were introduced, hypermobility syndrome was sometimes considered identical to hypermobile Ehlers–Danlos syndrome (hEDS), formerly called EDS Type 3. As no genetic test can distinguish the two conditions and because of the similarity of the diagnostic criteria and recommended treatments, many experts recommend they be recognized as the same condition until further research is undertaken.
In 2016 the diagnostic criteria for hEDS were re-written to be more restrictive, with the intent of narrowing the pool of hEDS patients in the hope of making it easier to identify a common genetic mutation, hEDS being the only EDS variant without a diagnostic DNA test. At the same time, joint hypermobility syndrome was renamed as hypermobility spectrum disorder and redefined as a hypermobility disorder that does not meet the diagnostic criteria for hEDS, other types of Ehlers-Danlos Syndrome, or other heritable Connective Tissue Disorder (such as Marfan's, Loeys-Dietz, or osteogenesis imperfecta).
Signs and symptoms
People with Joint Hypermobility Syndrome may develop other conditions caused by their unstable joints. These conditions include:
Joint instability causing frequent sprains, t
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https://en.wikipedia.org/wiki/Sun-4
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Sun-4 is a series of Unix workstations and servers produced by Sun Microsystems, launched in 1987. The original Sun-4 series were VMEbus-based systems similar to the earlier Sun-3 series, but employing microprocessors based on Sun's own SPARC V7 RISC architecture in place of the 68k family processors of previous Sun models.
Sun 4/280 was known as base system that was used for building of first RAID prototype.
Models
Models are listed in approximately chronological order.
{| class="wikitable sortable"
|-
!Model
!Codename
!CPU board
!CPU
!CPU MHz
!Max. RAM
!Chassis
|-
|4/260
|Sunrise
|Sun 4200
|Fujitsu SF9010 IU,Weitek 1164/1165 FPU
|16.67 MHz
|128 MB
|12-slot VME (deskside)
|-
|4/280
|Sunrise
|Sun 4200
|Fujitsu SF9010 IU,Weitek 1164/1165 FPU
|16.67 MHz
|128 MB
|12-slot VME (rackmount)
|-
|4/110
|Cobra
|Sun 4100
|Fujitsu MB86900 IU,Weitek 1164/1165 FPU(optional)
|14.28 MHz
|32 MB
|3-slot VME (desktop/side)
|-
|4/150
|Cobra
|Sun 4100
|Fujitsu MB86900 IU,Weitek 1164/1165 FPU(optional)
|14.28 MHz
|32 MB
|6-slot VME (deskside)
|-
|4/310
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|32 MB
|3-slot VME (desktop/side)
|-
|4/330
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|96 MB
|3-slot VME w 2 memory slots (deskside)
|-
|4/350
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|224 MB
|5-slot VME (desktop/side)
|-
|4/360
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|224 MB
|12-slot VME (deskside)
|-
|4/370
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|224 MB
|12-slot VME (deskside)
|-
|4/380
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|224 MB
|12-slot VME (rackmount)
|-
|4/390
|Stingray
|Sun 4300
|Cypress Semiconductor CY7C601,Texas Instruments 8847 FPU
|25 MHz
|224 MB
|16-slot VME (rackmount)
|-
|4/470
|Sunray
|Sun 4400
|Cypress Sem
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https://en.wikipedia.org/wiki/Homogeneously%20staining%20region
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Homogeneously staining regions (HSRs) are chromosomal segments with various lengths and uniform staining intensity after G banding. This type of aberration is also known as Copy Number Gains or Amplification.
An HSR is one type of change in a chromosome's structure which is frequently observed in the nucleus of human cancer cells. In the region of a chromosome where an HSR occurs, a segment of the chromosome, which presumably contains a gene or genes that give selective advantage to the progression of the cancer, is amplified or duplicated many times. As a result of the duplication this chromosomal segment is greatly lengthened and expanded such that when it is stained with a fluorescent probe specific to the region (Fluorescent in situ hybridization), rather than causing a focal fluorescent signal as in a normal chromosome, the probe "paints" a broad fluorescent signal over the whole of the amplified region. It is because of the appearance of this broadly staining region that this chromosomal abnormality was named a homogeneously staining region. The homogenously staining region was first observed in chromosome 2 by June Biedler and Barbara Spengler in cells that had been made resistant to methotrexate. The HSR was found to due to the amplification of the DHFR gene.
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https://en.wikipedia.org/wiki/Taylor%20expansions%20for%20the%20moments%20of%20functions%20of%20random%20variables
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In probability theory, it is possible to approximate the moments of a function f of a random variable X using Taylor expansions, provided that f is sufficiently differentiable and that the moments of X are finite.
First moment
Given and , the mean and the variance of , respectively, a Taylor expansion of the expected value of can be found via
Since the second term vanishes. Also, is . Therefore,
.
It is possible to generalize this to functions of more than one variable using multivariate Taylor expansions. For example,
Second moment
Similarly,
The above is obtained using a second order approximation, following the method used in estimating the first moment. It will be a poor approximation in cases where is highly non-linear. This is a special case of the delta method.
Indeed, we take .
With , we get . The variance is then computed using the formula
.
An example is,
The second order approximation, when X follows a normal distribution, is:
First product moment
To find a second-order approximation for the covariance of functions of two random variables (with the same function applied to both), one can proceed as follows. First, note that . Since a second-order expansion for has already been derived above, it only remains to find . Treating as a two-variable function, the second-order Taylor expansion is as follows:
Taking expectation of the above and simplifying—making use of the identities and —leads to . Hence,
Random vectors
If X is a random vector, the approximations for the mean and variance of are given by
Here and denote the gradient and the Hessian matrix respectively, and is the covariance matrix of X.
See also
Propagation of uncertainty
WKB approximation
Delta method
Notes
Further reading
Statistical approximations
Algebra of random variables
Moment (mathematics)
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https://en.wikipedia.org/wiki/Psophometric%20weighting
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Psophometric weighting refers to any weighting curve used in the measurement of noise. In the field of audio engineering it has a more specific meaning, referring to noise weightings used especially in measuring noise on telecommunications circuits. Key standards are ITU-T O.41 and C-message weighting as shown here.
Use
A major use of noise weighting is in the measurement of residual noise in audio equipment, usually present as hiss or hum in quiet moments of programme material. The purpose of weighting here is to emphasise the parts of the audible spectrum that ears perceive most readily, and attenuate the parts that contribute less to perception of loudness, in order to get a measured figure that correlates well with subjective effect.
See also
Audio system measurements
Equal-loudness contour
Fletcher–Munson curves
Noise measurement
Headroom
Psophometric voltage
Rumble measurement
ITU-R 468 noise weighting
A-weighting
Weighting filter
Weighting
Weighting curve
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https://en.wikipedia.org/wiki/Electrophoretic%20mobility%20shift%20assay
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An electrophoretic mobility shift assay (EMSA) or mobility shift electrophoresis, also referred as a gel shift assay, gel mobility shift assay, band shift assay, or gel retardation assay, is a common affinity electrophoresis technique used to study protein–DNA or protein–RNA interactions. This procedure can determine if a protein or mixture of proteins is capable of binding to a given DNA or RNA sequence, and can sometimes indicate if more than one protein molecule is involved in the binding complex. Gel shift assays are often performed in vitro concurrently with DNase footprinting, primer extension, and promoter-probe experiments when studying transcription initiation, DNA gang replication, DNA repair or RNA processing and maturation, as well as pre-mRNA splicing. Although precursors can be found in earlier literature, most current assays are based on methods described by Garner and Revzin and Fried and Crothers.
Principle
A mobility shift assay is electrophoretic separation of a protein–DNA or protein–RNA mixture on a polyacrylamide or agarose gel for a short period (about 1.5-2 hr for a 15- to 20-cm gel). The speed at which different molecules (and combinations thereof) move through the gel is determined by their size and charge, and to a lesser extent, their shape (see gel electrophoresis). The control lane (DNA probe without protein present) will contain a single band corresponding to the unbound DNA or RNA fragment. However, assuming that the protein is capable of binding to the fragment, the lane with a protein that binds present will contain another band that represents the larger, less mobile complex of nucleic acid probe bound to protein which is 'shifted' up on the gel (since it has moved more slowly).
Under the correct experimental conditions, the interaction between the DNA (or RNA) and protein is stabilized and the ratio of bound to unbound nucleic acid on the gel reflects the fraction of free and bound probe molecules as the binding reaction ent
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https://en.wikipedia.org/wiki/VAX-11
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The VAX-11 is a discontinued family of 32-bit superminicomputers, running the Virtual Address eXtension (VAX) instruction set architecture (ISA), developed and manufactured by Digital Equipment Corporation (DEC). Development began in 1976. In addition to being powerful machines in their own right, they also offer the additional ability to run user mode PDP-11 code (thus the -11 in VAX-11), offering an upward compatible path for existing customers.
The first machine in the series, the VAX-11/780, was announced in October 1977. Its former competitors in the minicomputer space, like Data General and Hewlett-Packard, were unable to successfully respond to the introduction and rapid update of the VAX design. DEC followed the VAX-11/780 with the lower-cost 11/750, and the even lower cost 11/730 and 11/725 models in 1982. More powerful models, initially known as the VAX-11/790 and VAX-11/795, were instead rebranded as the VAX 8600 series.
The VAX-11 line was discontinued in 1988, having been supplanted by the MicroVAX family on the low end, and the VAX 8000 family on the high end. The VAX-11/780 is historically one of the most successful and studied computers in history.
VAX-11/780
The VAX-11/780, code-named "Star", was introduced on 25 October 1977 at DEC's Annual Meeting of Shareholders. It is the first computer to implement the VAX architecture. The KA780 central processing unit (CPU) is built from Schottky transistor-transistor logic (TTL) devices and has a 200 ns cycle time (5 MHz) and a 2 KB cache. Memory and I/O are accessed via the Synchronous Backplane Interconnect (SBI).
The CPU is microprogrammed. The microcode is loaded at boot time from a 8” floppy disk controlled by a front end processor, a PDP-11/03, which was is used to run local and remote diagnostics.
The VAX-11/780 originally supported up to 8MB of memory through one or two MS780-C memory controllers, with each controller supporting between 128KB-4MB of memory. The later MS780-E memory controller
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https://en.wikipedia.org/wiki/Ancient%20Egyptian%20multiplication
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In mathematics, ancient Egyptian multiplication (also known as Egyptian multiplication, Ethiopian multiplication, Russian multiplication, or peasant multiplication), one of two multiplication methods used by scribes, is a systematic method for multiplying two numbers that does not require the multiplication table, only the ability to multiply and divide by 2, and to add. It decomposes one of the multiplicands (preferably the smaller) into a set of numbers of powers of two and then creates a table of doublings of the second multiplicand by every value of the set which is summed up to give result of multiplication.
This method may be called mediation and duplation, where mediation means halving one number and duplation means doubling the other number. It is still used in some areas.
The second Egyptian multiplication and division technique was known from the hieratic Moscow and Rhind Mathematical Papyri written in the seventeenth century B.C. by the scribe Ahmes.
Although in ancient Egypt the concept of base 2 did not exist, the algorithm is essentially the same algorithm as long multiplication after the multiplier and multiplicand are converted to binary. The method as interpreted by conversion to binary is therefore still in wide use today as implemented by binary multiplier circuits in modern computer processors.
Method
The ancient Egyptians had laid out tables of a great number of powers of two, rather than recalculating them each time. The decomposition of a number thus consists of finding the powers of two which make it up. The Egyptians knew empirically that a given power of two would only appear once in a number. For the decomposition, they proceeded methodically; they would initially find the largest power of two less than or equal to the number in question, subtract it out and repeat until nothing remained. (The Egyptians did not make use of the number zero in mathematics.)
After the decomposition of the first multiplicand, the person would constru
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https://en.wikipedia.org/wiki/Sensory%20neuroscience
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Sensory neuroscience is a subfield of neuroscience which explores the anatomy and physiology of neurons that are part of sensory systems such as vision, hearing, and olfaction. Neurons in sensory regions of the brain respond to stimuli by firing one or more nerve impulses (action potentials) following stimulus presentation. How is information about the outside world encoded by the rate, timing, and pattern of action potentials? This so-called neural code is currently poorly understood and sensory neuroscience plays an important role in the attempt to decipher it. Looking at early sensory processing is advantageous since brain regions that are "higher up" (e.g. those involved in memory or emotion) contain neurons which encode more abstract representations. However, the hope is that there are unifying principles which govern how the brain encodes and processes information. Studying sensory systems is an important stepping stone in our understanding of brain function in general.
Typical experiments
A typical experiment in sensory neuroscience involves the presentation of a series of relevant stimuli to an experimental subject while the subject's brain is being monitored. This monitoring can be accomplished by noninvasive means such as functional magnetic resonance imaging (fMRI) or electroencephalography (EEG), or by more invasive means such as electrophysiology, the use of electrodes to record the electrical activity of single neurons or groups of neurons. fMRI measures changes in blood flow which related to the level of neural activity and provides low spatial and temporal resolution, but does provide data from the whole brain. In contrast,
Electrophysiology provides very high temporal resolution (the shapes of single spikes can be resolved) and data can be obtained from single cells. This is important since computations are performed within the dendrites of individual neurons.
Single neuron experiments
In most of the central nervous system, neurons communicate ex
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https://en.wikipedia.org/wiki/Quantum%20metrology
|
Quantum metrology is the study of making high-resolution and highly sensitive measurements of physical parameters using quantum theory to describe the physical systems, particularly exploiting quantum entanglement and quantum squeezing. This field promises to develop measurement techniques that give better precision than the same measurement performed in a classical framework. Together with quantum hypothesis testing, it represents an important theoretical model at the basis of quantum sensing.
Mathematical foundations
A basic task of quantum metrology is estimating the parameter
of the unitary dynamics
where is the initial state of the system and is the Hamiltonian of the system. is estimated based on measurements on
Typically, the system is composed of many particles, and the Hamiltonian is a sum of single-particle terms
where acts on the kth particle. In this case, there is no interaction between the particles, and we talk about linear interferometers.
The achievable precision is bounded from below by the quantum Cramér-Rao bound as
where is the number of independent repetitions and is the quantum Fisher information.
Examples
One example of note is the use of the NOON state in a Mach–Zehnder interferometer to perform accurate phase measurements. A similar effect can be produced using less exotic states such as squeezed states. In quantum illumination protocols, two-mode squeezed states are widely studied to overcome the limit of classcial states represented in coherent states. In atomic ensembles, spin squeezed states can be used for phase measurements.
Applications
An important application of particular note is the detection of gravitational radiation in projects such as LIGO or the Virgo interferometer, where high-precision measurements must be made for the relative distance between two widely separated masses. However, the measurements described by quantum metrology are currently not used in this setting, being difficult to implement. F
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https://en.wikipedia.org/wiki/Path%20expression
|
In query languages, path expressions identify an object by describing how to navigate to it
in some graph (possibly implicit) of objects. For example, the path expression p.Manager.Home.City might refer the city of residence of someone's manager.
Path expressions have been extended to support regular expression-like flexibility.
XPath is an example of a path expression language.
In concurrency control, path expressions are a mechanism for expressing permitted sequences of execution. For example, a path expression like " {read}, write" might specify that either multiple simultaneous executions of read or a single execution of write but not both are allowed at any point in time.
It is important to know that the path expressions are a mechanism for the synchronization of processes at the monitor level in the software. That provides a clear and structured approach to the description of shared data and the coordination and communication between concurrent processes. This method is flexible in its ability to express timing, and can be used in different ways.
In addition, path expressions are useful for process synchronization for two reasons: first, the close relationship between stream expressions and regular expressions that simplify the task of writing and reasoning about programs that use this synchronization mechanism. Second, synchronization in many concurrent programs in a finite state, and therefore can be adequately described by regular expressions. For precisely the same reasons, path expressions are useful for controlling the behavior of complicated asynchronous circuits. In fact, the finite state assumption may be even more reasonable at the hardware level than at the monitor level.
Path expressions provide a high level of descriptive synchronization that aids in the prevention and detection of design errors in complex systems and overcomes some of the dangers, such as certain forms of coding errors.
See also
Object database
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https://en.wikipedia.org/wiki/Baire%20set
|
In mathematics, more specifically in measure theory, the Baire sets form a σ-algebra of a topological space that avoids some of the pathological properties of Borel sets.
There are several inequivalent definitions of Baire sets, but in the most widely used, the Baire sets of a locally compact Hausdorff space form the smallest σ-algebra such that all compactly supported continuous functions are measurable. Thus, measures defined on this σ-algebra, called Baire measures, are a convenient framework for integration on locally compact Hausdorff spaces. In particular, any compactly supported continuous function on such a space is integrable with respect to any finite Baire measure.
Every Baire set is a Borel set. The converse holds in many, but not all, topological spaces. Baire sets avoid some pathological properties of Borel sets on spaces without a countable base for the topology. In practice, the use of Baire measures on Baire sets can often be replaced by the use of regular Borel measures on Borel sets.
Baire sets were introduced by , and , who named them after Baire functions, which are in turn named after René-Louis Baire.
Basic definitions
There are at least three inequivalent definitions of Baire sets on locally compact Hausdorff spaces, and even more definitions for general topological spaces, though all these definitions are equivalent for locally compact σ-compact Hausdorff spaces. Moreover, some authors add restrictions on the topological space that Baire sets are defined on, and only define Baire sets on spaces that are compact Hausdorff, or locally compact Hausdorff, or σ-compact.
First definition
Kunihiko Kodaira defined what we call Baire sets (although he confusingly calls them "Borel sets") of certain topological spaces to be the sets whose characteristic function is a Baire function (the smallest class of functions containing all continuous real-valued functions and closed under pointwise limits of sequences).
gives an equivalent defini
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https://en.wikipedia.org/wiki/Geodemographic%20segmentation
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In marketing, geodemographic segmentation is a multivariate statistical classification technique for discovering whether the individuals of a population fall into different groups by making quantitative comparisons of multiple characteristics with the assumption that the differences within any group should be less than the differences between groups.
Principles
Geodemographic segmentation is based on two simple principles:
People who live in the same neighborhood are more likely to have similar characteristics than are two people chosen at random.
Neighborhoods can be categorized in terms of the characteristics of the population which they contain. Any two neighborhoods can be placed in the same category, i.e., they contain similar types of people, even though they are widely separated.
Clustering algorithms
The use of different algorithms leads to different results, but there is no single best approach for selecting the best algorithm, just as no algorithm offers any theoretical proof of its certainty. One of the most frequently used techniques in geodemographic segmentation is the widely known k-means clustering algorithm. In fact most of the current commercial geodemographic systems are based on a k-means algorithm. Still, clustering techniques coming from artificial neural networks, genetic algorithms, or fuzzy logic are more efficient within large, multidimensional databases (Brimicombe 2007).
Neural networks can handle non-linear relationships, are robust to noise and exhibit a high degree of automation. They do not assume any hypotheses regarding the nature or distribution of the data and they provide valuable assistance in handling problems of a geographical nature that, to date, have been impossible to solve. One of the best known and most efficient neural network methods for achieving unsupervised clustering is the Self-Organizing Map (SOM). SOM has been proposed as an improvement over the k-means method, for it provides a more flexible approach to
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https://en.wikipedia.org/wiki/Inverse%20demand%20function
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In economics, an inverse demand function is the mathematical relationship that expresses price as a function of quantity demanded (is is therefore also known as a price function).
Historically, the economists first expressed the price of a good as a function of demand (holding the other economic variables, like income, constant), and plotted the price-demand relationship with demand on the x (horizontal) axis (the demand curve). Later the additional variables, like prices of other goods, came into analysis, and it became more convenient to express the demand as a multivariate function (the demand function):
, so the original demand curve now depicts the inverse demand function with extra variables fixed.
Definition
In mathematical terms, if the demand function is , then the inverse demand function is . The value of the inverse demand function is the highest price that could be charged and still generate the quantity demanded. This is useful because economists typically place price (P) on the vertical axis and quantity (demand, Q) on the horizontal axis in supply-and-demand diagrams, so it is the inverse demand function that depicts the graphed demand curve in the way the reader expects to see.
The inverse demand function is the same as the average revenue function, since P = AR.
To compute the inverse demand function, simply solve for P from the demand function. For example, if the demand function has the form then the inverse demand function would be . Note that although price is the dependent variable in the inverse demand function, it is still the case that the equation represents how the price determines the quantity demanded, not the reverse.
Relation to marginal revenue
There is a close relationship between any inverse demand function for a linear demand equation and the marginal revenue function. For any linear demand function with an inverse demand equation of the form P = a - bQ, the marginal revenue function has the form MR = a - 2bQ. The invers
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https://en.wikipedia.org/wiki/Vaccine%20adverse%20event
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A vaccine adverse event (VAE), sometimes referred to as a vaccine injury, is an adverse event caused by vaccination. The World Health Organization (WHO) knows VAEs as Adverse Events Following Immunization (AEFI).
AEFIs can be related to the vaccine itself (product or quality defects), to the vaccination process (administration error or stress related reactions) or can occur independently from vaccination (coincidental).
Most vaccine adverse events are mild. Serious injuries and deaths caused by vaccines are very rare, and the idea that severe events are common has been classed as a "common misconception about immunization" by the WHO. Some claimed vaccine injuries are not, in fact, caused by vaccines; for example, there is a subculture of advocates who attribute their children's autism to vaccine injury, despite the fact that vaccines do not cause autism.
Claims of vaccine injuries appeared in litigation in the United States in the latter part of the 20th century. Some families have won substantial awards from sympathetic juries, even though many public health officials have said that the claims of injuries are unfounded. In response, several vaccine makers stopped production, threatening public health, resulting in laws being passed to shield makers from liabilities stemming from vaccine injury claims.
Adverse events
According to the U.S. Centers for Disease Control and Prevention, while "any vaccine can cause side effects", most side effects are minor, primarily including sore arms or a mild fever. Unlike most medical interventions vaccines are given to healthy people, where the risk of side effects is not as easily outweighed by the benefit of treating existing disease. As such, the safety of immunization interventions is taken very seriously by the scientific community, with constant monitoring of a number of data sources looking for patterns of adverse events.
As the success of immunization programs increases and the incidence of disease decreases, publi
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https://en.wikipedia.org/wiki/Mohammad-Ali%20Najafi
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Mohammad-Ali Najafi (; born 13 January 1952) is an Iranian mathematician and reformist politician who was the Mayor of Tehran, serving in the post for eight months, until April 2018. He held cabinet portfolios during the 1980s, 1990s and 2010s. He is also a retired professor of mathematics at Sharif University of Technology.
Early life and education
Najafi was born in Tehran on 13 January 1952. He ranked first in Iranian national university entrance exam and enrolled in Sharif University of Technology (then known as Aryamehr University of Technology). He earned a Bachelor of Science degree in mathematics from the Sharif University of Technology. Following his bachelors, he enrolled in the graduate program at the Massachusetts Institute of Technology. He received his Master of Science degree in mathematics with the final grade of A+ in 1976 but dropped out of PhD program in 1978 during the Iranian revolution to return to Iran.
Career
Following the Iranian revolution of 1979, Najafi returned to Iran and became a faculty member at Isfahan University of Technology in 1979 and he was the chair of the university from 1980 to 1981. He was a faculty member at department of mathematical sciences in Sharif University of Technology from 1984 to 1988, when he moved to government.
At the end of the reformist government of Mohammad Khatami and following Mahmoud Ahmadinejad's election Najafi moved back to university and has been faculty in the department of mathematics at Sharif University of Technology working on representation theory.
He served as an advisor to Mostafa Chamran. He was the minister of higher education from 1981 to 1984 in the cabinet of then Prime Minister Mir-Hossein Mousavi. In 1989, he became the minister of education under then President Hashemi Rafsanjani and served until 1997. In 1997, he was appointed vice president and head of the Planning and Budget Organization by President Mohammad Khatami, but after a merge of the organization with another he was
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https://en.wikipedia.org/wiki/Correlation%20sum
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In chaos theory, the correlation sum is the estimator of the correlation integral, which reflects the mean probability that the states at two different times are close:
where is the number of considered states , is a threshold distance, a norm (e.g. Euclidean norm) and the Heaviside step function. If only a time series is available, the phase space can be reconstructed by using a time delay embedding (see Takens' theorem):
where is the time series, the embedding dimension and the time delay.
The correlation sum is used to estimate the correlation dimension.
See also
Recurrence quantification analysis
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https://en.wikipedia.org/wiki/Building%20information%20modeling
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Building information modeling (BIM) is a process involving the generation and management of digital representations of the physical and functional characteristics of places. BIM is supported by various tools, technologies and contracts. Building information models (BIMs) are computer files (often but not always in proprietary formats and containing proprietary data) which can be extracted, exchanged or networked to support decision-making regarding a built asset. BIM software is used by individuals, businesses and government agencies who plan, design, construct, operate and maintain buildings and diverse physical infrastructures, such as water, refuse, electricity, gas, communication utilities, roads, railways, bridges, ports and tunnels.
The concept of BIM has been in development since the 1970s, but it only became an agreed term in the early 2000s. The development of standards and the adoption of BIM has progressed at different speeds in different countries. Standards developed in the United Kingdom from 2007 onwards have formed the basis of the international standard ISO 19650, launched in January 2019.
History
The concept of BIM has existed since the 1970s. The first software tools developed for modeling buildings emerged in the late 1970s and early 1980s, and included workstation products such as Chuck Eastman's Building Description System and GLIDE, RUCAPS, Sonata, Reflex and Gable 4D Series. The early applications, and the hardware needed to run them, were expensive, which limited widespread adoption.
The pioneering role of applications such as RUCAPS, Sonata and Reflex has been recognized by Laiserin as well as the UK's Royal Academy of Engineering; former GMW employee Jonathan Ingram worked on all three products. What became known as BIM products differed from architectural drafting tools such as AutoCAD by allowing the addition of further information (time, cost, manufacturers' details, sustainability, and maintenance information, etc.) to the buildi
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https://en.wikipedia.org/wiki/Lady%20of%20the%20Mountain
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The Lady of the Mountain () is the female incarnation (national personification) of Iceland.
History in Iceland
The personification of a nation as a woman was widespread in eighteenth- and nineteenth-century Europe. The earliest image of Iceland personified as a woman seems to have appeared first in association with the poem Ofsjónir við jarðarför Lovísu drottningar 1752 ('Visions at the funeral of Queen Louise, 1752') by Eggert Ólafsson (1752), but this image does not survive.
The word fjallkonan is attested for the first time in the poem Eldgamla Ísafold by Bjarni Thorarensen from the first decade of the nineteenth century. From that moment onwards the Lady of the Mountain became a well-known symbol in Icelandic poetry.
An image of Lady of the Mountain was published in the last volume of an English translation of Icelandic folk-tales by Eiríkur Magnússon and G. E. J. Powell, Icelandic Legends, Collected by Jón Arnason (1864–66). It is the work of the German painter Johann Baptist Zwecker, who drew it to specifications provided by Eiríkur. Eiríkur described the picture in a letter to Jón Sigurðsson (11 April 1866) thus:
The picture of the woman is to represent Iceland, thus she has a crown of ice on her head, from which fires erupt. On her shoulder is the raven, Iceland's most characteristic bird, Óðinn's ancient friend and the favourite of poets, a great and knowledgeable carrier of news. Over the seas flutters a seagull, but across the surf of time and history are borne rune-staves to the land and up into the embrace of the woman, and she has picked one of them up. This is intended as a symbol of our land of literature and history. It is night, with a starry sky and the moon up. Behind are mountains, moonlight on the ridges.
Also very popular is the image designed by Benedikt Gröndal on a memorial card of the national holiday in 1874.
Since the establishment of the Icelandic republic in 1944 it has been traditional for a woman to play the role of the Lad
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https://en.wikipedia.org/wiki/Look-ahead%20%28backtracking%29
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In backtracking algorithms, look ahead is the generic term for a subprocedure that attempts to foresee the effects of choosing a branching variable to evaluate one of its values. The two main aims of look-ahead are to choose a variable to evaluate next and to choose the order of values to assign to it.
Constraint satisfaction
In a general constraint satisfaction problem, every variable can take a value in a domain. A backtracking algorithm therefore iteratively chooses a variable and tests each of its possible values; for each value the algorithm is recursively run. Look ahead is used to check the effects of choosing a given variable to evaluate or to decide the order of values to give to it.
Look ahead techniques
The simpler technique for evaluating the effect of a specific assignment to a variable is called forward checking. Given the current partial solution and a candidate assignment to evaluate, it checks whether another variable can take a consistent value. In other words, it first extends the current partial solution with the tentative value for the considered variable; it then considers every other variable that is still unassigned, and checks whether there exists an evaluation of that is consistent with the extended partial solution. More generally, forward checking determines the values for that are consistent with the extended assignment.
A look-ahead technique that may be more time-consuming but may produce better results is based on arc consistency. Namely, given a partial solution extended with a value for a new variable, it enforces arc consistency for all unassigned variables. In other words, for any unassigned variables, the values that cannot consistently be extended to another variable are removed. The difference between forward checking and arc consistency is that the former only checks a single unassigned variable at time for consistency, while the second also checks pairs of unassigned variables for mutual consistency. The most common wa
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https://en.wikipedia.org/wiki/IEEE%20802.1ag
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IEEE 802.1ag is an amendment to the IEEE 802.1Q networking standard which introduces Connectivity Fault Management (CFM). This defines protocols and practices for the operations, administration, and maintenance (OAM) of paths through 802.1 bridges and local area networks (LANs). The final version was approved by the IEEE in 2007.
IEEE 802.1ag is a subset of the earlier ITU-T Recommendation Y.1731, which additionally addresses performance monitoring.
The standard:
Defines maintenance domains, their constituent maintenance points, and the managed objects required to create and administrate them
Defines the relationship between maintenance domains and the services offered by VLAN-aware bridges and provider bridges
Describes the protocols and procedures used by maintenance points to maintain and diagnose connectivity faults within a maintenance domain;
Provides means for future expansion of the capabilities of maintenance points and their protocols
Definitions
The document defines various terms:
Maintenance Domain (MD) Maintenance Domains are management space on a network, typically owned and operated by a single entity. MDs are configured with Names and Levels, where the eight levels range from 0 to 7. A hierarchical relationship exists between domains based on levels. The larger the domain, the higher the level value. Recommended values of levels are as follows:
Customer Domain: Largest (e.g., 7)
Provider Domain: In between (e.g., 3)
Operator Domain: Smallest (e.g., 1)
Maintenance Association (MA) Defined as a "set of MEPs, all of which are configured with the same MAID (Maintenance Association Identifier) and MD Level, each of which is configured with a MEPID unique within that MAID and MD Level, and all of which are configured with the complete list of MEPIDs."
Maintenance association End Point (MEP) Points at the edge of the domain, define the boundary for the domain. A MEP sends and receives CFM frames through the relay function, drops all CFM frames of its
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https://en.wikipedia.org/wiki/Exogenote
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An exogenote is a piece of donor DNA that is involved in the mating of prokaryotic organisms.
Transferred DNA of Hfr (high frequency of recombination) is called exogenote and homologous part of F (fertility factor) genophore is called endogenote. An exogenote is genetic material that is released into the environment by prokaryotic cells, usually upon their lysis. This exogenous genetic material is then free to be taken up by other competent bacteria, and used as a template for protein synthesis or broken down for its molecules to be used elsewhere in the cell. Taking up genetic material into the cell from the surrounding environment is a form of bacterial transformation. Exogenotes can also be transferred directly from donor to recipient bacteria as an F'-plasmid in a process known as bacterial conjugation. F'-plasmids only form if the F+ factor is incorrectly translated, and results in a small amount of donor DNA erroneously transferring to the recipient with very high efficiency.
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https://en.wikipedia.org/wiki/File%20comparison
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In computing, file comparison is the calculation and display of the differences and similarities between data objects, typically text files such as source code.
The methods, implementations, and results are typically called a diff, after the Unix diff utility. The output may be presented in a graphical user interface or used as part of larger tasks in networks, file systems, or revision control.
Some widely used file comparison programs are diff, cmp, FileMerge, WinMerge, Beyond Compare, and File Compare.
Many text editors and word processors perform file comparison to highlight the changes to a file or document.
Method types
Most file comparison tools find the longest common subsequence between two files. Any data not in the longest common subsequence is presented as a change or an insertion or a deletion.
In 1978, Paul Heckel published an algorithm that identifies most moved blocks of text. This is used in the IBM History Flow tool. Other file comparison programs find block moves.
Some specialized file comparison tools find the longest increasing subsequence between two files. The rsync protocol uses a rolling hash function to compare two files on two distant computers with low communication overhead.
File comparison in word processors is typically at the word level, while comparison in most programming tools is at the line level. Byte or character-level comparison is useful in some specialized applications.
Display
Display of file comparison varies, with the main approaches being either showing two files side-by-side, or showing a single file, with markup showing the changes from one file to the other. In either case, particularly side-by-side viewing, code folding or text folding may be used to hide unchanged portions of the file, only showing the changed portions.
Reasoning
Comparison tools are used for various reasons. When one wishes to compare binary files, byte-level is probably best. But if one wishes to compare text files or computer progr
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https://en.wikipedia.org/wiki/Shadow%20and%20highlight%20enhancement
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Shadow and highlight enhancement refers to an image processing technique used to correct exposure.
The use of this technique has been gaining popularity, making its way onto magazine covers, digital media, and photos. It is, however, considered by some to be akin to other destructive Photoshop filters, such as the Watercolor filter, or the Mosaic filter.
Shadow recovery
A conservative application of the shadow/highlight tool can be very useful in recovering shadows, though it tends to leave a telltale halo around the boundary between highlight and shadow if used incorrectly. A way to avoid this is to use the bracketing technique, although this usually requires a tripod.
Highlight recovery
Recovering highlights with this tool, however, has mixed results, especially when using it on images with skin in them, and often makes people look like they have been "sprayed with fake tan".
Shadow brightening - manual
One way to brighten shadows in image editing software such as GIMP or Adobe Photoshop is to duplicate the background layer, invert the copy and set the blend modes of that top layer to "Soft Light". You can also use an inverted black and white copy of the image as a mask on a brightening layer, such as Curves or Levels.
Shadow brightening - automatic
Several automatic computer image processing-based shadow recovery and dynamic range compression methods can yield a similar effect. Some of these methods include the retinex method and homomorphic range compression. The retinex method is based on work from 1963 by Edwin Land, the founder of Polaroid.
Shadow enhancement can also be accomplished using adaptive image processing algorithms such as adaptive histogram equalization or contrast limiting adaptive histogram equalization (CLAHE).
See also
HDR PhotoStudio — an HDR image editing tool that implements an advanced Shadow/highlight algorithm with halo reduction technique.
Tone mapping
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https://en.wikipedia.org/wiki/Operculum%20%28botany%29
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In botany, an operculum () or calyptra () is a cap-like structure in some flowering plants, mosses, and fungi. It is a covering, hood or lid, describing a feature in plant morphology.
Flowering plants
In flowering plants, the operculum, also known as a calyptra, is the cap-like covering or "lid" of the flower or fruit that detaches at maturity. The operculum is formed by the fusion of sepals and/or petals and is usually shed as a single structure as the flower or fruit matures. The name is also used for the capping tissue of roots, the root cap.
In eucalypts, (including Eucalyptus and Corymbia but not Angophora) there may be two opercula – an outer operculum formed by the fusion of the united sepals and an inner operculum formed by the fusion of the sepals. In that case, the outer operculum is shed early in the development of the bud leaving a scar around the bud. In those species that lack an outer operculum, there is no bud scar. The inner operculum is shed just before flowering, when the stamens expand and shed their pollen.
In some species of monocotyledon, the operculum is an area of exine covering the pollen aperture.
In Plantago, the capsule has an opening covered by an operculum. When the operculum falls, the seed is sticky and is easily carried by animals that come into contact with it.
Pitcher plants have an operculum above the pitcher that serves to keep out rainwater that would otherwise dilute the digestive juices in the pitcher.
Bryophytes
In bryophytes, the calyptra (plural calyptrae) is an enlarged archegonial venter that protects the capsule containing the embryonic sporophyte. The calyptra is usually lost before the spores are released from the capsule. The shape of the calyptra can be used for identification purposes.
The sporangium of mosses usually opens when its operculum or "lid" falls off, exposing a ring of teeth that control the release of spores.
Fungi
There are two types of sexual spore-bearing asci of ascomycete fungi – those tha
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https://en.wikipedia.org/wiki/Computational%20scientist
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A computational scientist is a person skilled in scientific computing. This person is usually a scientist, a statistician, an applied mathematician, or an engineer who applies high-performance computing and sometimes cloud computing in different ways to advance the state-of-the-art in their respective applied discipline; physics, chemistry, social sciences and so forth. Thus scientific computing has increasingly influenced many areas such as economics, biology, law, and medicine to name a few. Because a computational scientist's work is generally applied to science and other disciplines, they are not necessarily trained in computer science specifically, though concepts of computer science are often used. Computational scientists are typically researchers at academic universities, national labs, or tech companies.
One of the tasks of a computational scientist is to analyze large amounts of data, often from astrophysics or related fields, as these can often generate huge amounts of data. Computational scientists often have to clean up and calibrate the data to a usable form for an effective analysis. Computational scientists are also tasked with creating artificial data through computer models and simulations.
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https://en.wikipedia.org/wiki/Longest%20repeated%20substring%20problem
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In computer science, the longest repeated substring problem is the problem of finding the longest substring of a string that occurs at least twice.
This problem can be solved in linear time and space by building a suffix tree for the string (with a special end-of-string symbol like '$' appended), and finding the deepest internal node in the tree with more than one child. Depth is measured by the number of characters traversed from the root. The string spelled by the edges from the root to such a node is a longest repeated substring. The problem of finding the longest substring with at least occurrences can be solved by first preprocessing the tree to count the number of leaf descendants for each internal node, and then finding the deepest node with at least leaf descendants. To avoid overlapping repeats, you can check that the list of suffix lengths has no consecutive elements with less than prefix-length difference.
In the figure with the string "ATCGATCGA$", the longest substring that repeats at least twice is "ATCGA".
External links
C implementation of Longest Repeated Substring using Suffix Tree
Online Demo: Longest Repeated Substring
Problems on strings
Formal languages
Combinatorics
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https://en.wikipedia.org/wiki/LZWL
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LZWL is a syllable-based variant of the character-based LZW compression algorithm that can work with syllables obtained by all algorithms of decomposition into syllables. The algorithm can be used for words too.
Algorithm
Algorithm LZWL can work with syllables obtained by all algorithms of decomposition into syllables. This algorithm can be used for words too.
In the initialization step, the dictionary is filled up with all characters from the alphabet. In each next step, it is searched for the maximal string , which is from the dictionary and matches the prefix of the still non-coded part of the input. The number of phrase is sent to the output. A new phrase is added to the dictionary. This phrase is created by concatenation of string S and the character that follows in the file. The actual input position is moved forward by the length of .
Decoding has only one situation for solving. We can receive the number of phrase, which is not from the dictionary. In this case, that phrase can be created by the concatenation of the last added phrase with its first character.
The syllable-based version uses a list of syllables as an alphabet. In the initialization step, the empty syllable and small syllables from a database of frequent syllables are added to the dictionary. Finding string and coding its number is similar to the character-based version, except that string is a string of syllables. The number of phrase is encoded to the output. The string can be the empty syllable.
If is the empty syllable, then we must get from the file one syllable and encode by methods for coding new syllables. Syllable is added to the dictionary. The position in the file is moved forward by the length of . In the case when S is the empty syllable, the input position is moved forward by the length of .
In adding a phrase to the dictionary there is a difference in the character-based version. The phrase from the next step will be called S1. If and S1 are both non-empty syllabl
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https://en.wikipedia.org/wiki/Eigenspinor
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In quantum mechanics, eigenspinors are thought of as basis vectors representing the general spin state of a particle. Strictly speaking, they are not vectors at all, but in fact spinors. For a single spin 1/2 particle, they can be defined as the eigenvectors of the Pauli matrices.
General eigenspinors
In quantum mechanics, the spin of a particle or collection of particles is quantized. In particular, all particles have either half integer or integer spin. In the most general case, the eigenspinors for a system can be quite complicated. If you have a collection of the Avogadro number of particles, each one with two (or more) possible spin states, writing down a complete set of eigenspinors would not be practically possible. However, eigenspinors are very useful when dealing with the spins of a very small number of particles.
The spin 1/2 particle
The simplest and most illuminating example of eigenspinors is for a single spin 1/2 particle. A particle's spin has three components, corresponding to the three spatial dimensions: , , and . For a spin 1/2 particle, there are only two possible eigenstates of spin: spin up, and spin down. Spin up is denoted as the column matrix:
and spin down is
.
Each component of the angular momentum thus has two eigenspinors. By convention, the z direction is chosen as having the and states as its eigenspinors. The eigenspinors for the other two orthogonal directions follow from this convention:
:
:
:
All of these results are but special cases of the eigenspinors for the direction specified by θ and φ in spherical coordinates - those eigenspinors are:
Example usage
Suppose there is a spin 1/2 particle in a state . To determine the probability of finding the particle in a spin up state, we simply multiply the state of the particle by the adjoint of the eigenspinor matrix representing spin up, and square the result. Thus, the eigenspinor allows us to sample the part of the particle's state that is in the same direct
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https://en.wikipedia.org/wiki/Iru%20%28food%29
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Irú (Yoruba) locust beans (English) or Eware (Edo) is a type of fermented and processed locust beans (Parkia biglobosa) used as a condiment in cooking. It is similar to ogiri and douchi. It is very popular among the Yoruba people and Edo people of Nigeria. It is used in cooking traditional soups like egusi soup, okro soup (ILA), Ewedu soup, and ogbono soup.
Iru production
Among the Manding-speaking people of West Africa irú is known as sumbala. The Yorubas classify iru into two types:
Irú Wooro is used mostly in vegetable soups like Efo Riro, Egusi soup, Ofada sauce, Ayamashe, Buka stew, Obe ata, Ila Asepo, etc.
Irú pẹ̀tẹ̀ is used in making ewedu and egusi soup.
During fermentation, the reducing sugar content increases, and the total free amino acid content initially decreases; in the end, however, there is a large increase in free amino acid content.
See also
List of African dishes
Sumbala
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https://en.wikipedia.org/wiki/Vesiculovirus
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Vesiculovirus is a genus of negative-sense single-stranded RNA viruses in the family Rhabdoviridae, within the order Mononegavirales.
Taxonomy
The genus contains the following species:
Alagoas vesiculovirus
Carajas vesiculovirus
Chandipura vesiculovirus
Cocal vesiculovirus
Eptesicus vesiculovirus
Indiana vesiculovirus
Isfahan vesiculovirus
Jurona vesiculovirus
Malpais Spring vesiculovirus
Maraba vesiculovirus
Morreton vesiculovirus
New Jersey vesiculovirus
Perinet vesiculovirus
Piry vesiculovirus
Radi vesiculovirus
Rhinolophus vesiculovirus
Yug Bogdanovac vesiculovirus
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https://en.wikipedia.org/wiki/Epsilon%20number
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In mathematics, the epsilon numbers are a collection of transfinite numbers whose defining property is that they are fixed points of an exponential map. Consequently, they are not reachable from 0 via a finite series of applications of the chosen exponential map and of "weaker" operations like addition and multiplication. The original epsilon numbers were introduced by Georg Cantor in the context of ordinal arithmetic; they are the ordinal numbers ε that satisfy the equation
in which ω is the smallest infinite ordinal.
The least such ordinal is ε0 (pronounced epsilon nought or epsilon zero), which can be viewed as the "limit" obtained by transfinite recursion from a sequence of smaller limit ordinals:
where is the supremum function, which is equivalent to set union in the case of the von Neumann representation of ordinals.
Larger ordinal fixed points of the exponential map are indexed by ordinal subscripts, resulting in . The ordinal ε0 is still countable, as is any epsilon number whose index is countable (there exist uncountable ordinals, and uncountable epsilon numbers whose index is an uncountable ordinal).
The smallest epsilon number ε0 appears in many induction proofs, because for many purposes, transfinite induction is only required up to ε0 (as in Gentzen's consistency proof and the proof of Goodstein's theorem). Its use by Gentzen to prove the consistency of Peano arithmetic, along with Gödel's second incompleteness theorem, show that Peano arithmetic cannot prove the well-foundedness of this ordering (it is in fact the least ordinal with this property, and as such, in proof-theoretic ordinal analysis, is used as a measure of the strength of the theory of Peano arithmetic).
Many larger epsilon numbers can be defined using the Veblen function.
A more general class of epsilon numbers has been identified by John Horton Conway and Donald Knuth in the surreal number system, consisting of all surreals that are fixed points of the base ω exponential map
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https://en.wikipedia.org/wiki/German%20locomotive%20classification
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The different railway companies in Germany have used various schemes to classify their rolling stock.
From the beginning
As widely known the first few locomotives had names. The first locomotive in public service in Germany from 1835 was named Adler. The first railway lines were built by privately owned companies. That changed later when many railway companies were taken over or founded by the respective German states such as Prussia, Bavaria, etc.
Different numbering schemes prior to 1924
The fast-growing number of locomotives made a numbering scheme inevitable. Most of the various state-owned German railway companies (called Länderbahnen in German) developed their own schemes, e. g. the Prussian state railways (preußische Staatseisenbahnen sometimes erroneously referred to as the Königlich Preussische Eisenbahn-Verwaltung or KPEV) introduced P for passenger train locomotives (the P 8 was one of the most important locomotive types with a total of over 3,000 units built), S for Schnellzug (express train) locomotives (e. g. the famous S 10), G for Güterzug (freight train) locomotives and T for Tenderlokomotive (tank locomotive). Basically the numbers were used continuously. As the Prussians also standardised technical standards, some of the smaller companies also used the Prussian numbering scheme or a similar one.
Bavaria's state-owned railway chose a different way: They also used P, S, or G to indicate the train type, but combined with the numbers of driving axles and of the axles in total, separated by a slash (similar to the Swiss system). E. g., the famous S 3/6 was a 2'C1' or 4-6-2 Pacific, meaning that of a total of 6 axles, 3 were driving axles.
These various state-owned companies and thus their numbering schemes were retained after German unification in 1871 and kept until well after World War I.
The first uniform scheme
The Deutsche Reichsbahn-Gesellschaft DRG was founded in 1924 by the amalgamation of the various state-owned Länderbahnen. One of its
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https://en.wikipedia.org/wiki/Oceans%20Act%20of%202000
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The Oceans Act of 2000 established the United States Commission on Ocean Policy, a working group tasked with the development of what would be known as the National Oceans Report.
The objective of the report is to promote the following:
Protection of life and property;
Stewardship of ocean and coastal resources;
Protection of marine environment and prevention of marine pollution;
Enhancement of maritime commerce;
Expansion of human knowledge of the marine environment;
Investments in technologies to promote energy and food security;
Close cooperation among government agencies; and
U.S. leadership in ocean and coastal activities.
Responses from the executive branch to the commission's report are listed in a National Ocean Policy, sent to the legislative branch.
The act was passed by the United States Congress on July 25, 2000 and signed by the President a fortnight later.
The Commission
Has 16 members
U.S. House and U.S. Senate Majority nominate 8 people each and the U.S. President appoints 4 from each list
U.S. House and U.S. Senate Minority nominates 4 people each and the U.S. President appoints 2 from each
4 people self-determined by U.S. President
Chair: supervises commission staff and regulates funding.
Members must be "balanced by area of expertise and balanced geographically".
To be eligible, members must be "Representatives, knowledgeable in ocean and coastal activities, from state and local governments, ocean-related industries, academic and technical institutions, and public interest organizations involved with scientific, regulatory, economic, and environmental ocean and coastal activities." (https://web.archive.org/web/20060207190735/http://www.oceancommission.gov/documents/oceanact.html)
The Commission's report is required to include the following, as relevant to U.S. ocean and coastal activities:
an assessment of facilities (people, vessels, computers, satellites)
a review of federal activities
a review of the cumulative effect of
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https://en.wikipedia.org/wiki/List%20of%20contaminated%20cell%20lines
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Many cell lines that are widely used for biomedical research have been overgrown by other, more aggressive cells. For example, supposed thyroid lines were actually melanoma cells, supposed prostate tissue was actually bladder cancer, and supposed normal uterine cultures were actually breast cancer. This is a list of cell lines that have been cross-contaminated and overgrown by other cells. Estimates based on screening of leukemia-lymphoma cell lines suggest that about 15% of these cell lines are not representative of what they are usually assumed to be. A project is currently underway to enumerate and rename contaminated cell lines to avoid errors in research caused by misattribution.
Contaminated cell lines have been extensively used in research without knowledge of their true character. For example, most if not all research on the endothelium ECV-304 or the megakaryocyte DAMI cell lines has in reality been conducted on bladder carcinoma and erythroleukemia cells, respectively. Thus, all research on endothelium- or megakaryocyte-specific functions utilizing these cell lines has turned out to be misguided, serving more of a warning example.
There are two principal ways a cell line can become contaminated: cell cultures are often exchanged between research groups; if, during handling, a sample gets contaminated and then passed on, subsequent exchanges of cells will lead to the contaminating population being established, although parts of the supposed cell line are still genuine. More serious is contamination at the source: during establishment of the original cell line, some contaminating cells are accidentally introduced into the cultures, where they in time outgrow the desired cells. The initial testing, in this case, still suggested that the cell line is genuine and novel, but in reality, it has disappeared soon after being established and all samples of such cell lines are actually the contaminant cells. It requires lengthy research to determine the precise poi
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https://en.wikipedia.org/wiki/Linear%20group
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In mathematics, a matrix group is a group G consisting of invertible matrices over a specified field K, with the operation of matrix multiplication. A linear group is a group that is isomorphic to a matrix group (that is, admitting a faithful, finite-dimensional representation over K).
Any finite group is linear, because it can be realized by permutation matrices using Cayley's theorem. Among infinite groups, linear groups form an interesting and tractable class. Examples of groups that are not linear include groups which are "too big" (for example, the group of permutations of an infinite set), or which exhibit some pathological behavior (for example, finitely generated infinite torsion groups).
Definition and basic examples
A group G is said to be linear if there exists a field K, an integer d and an injective homomorphism from G to the general linear group GLd(K) (a faithful linear representation of dimension d over K): if needed one can mention the field and dimension by saying that G is linear of degree d over K. Basic instances are groups which are defined as subgroups of a linear group, for example:
The group GLn(K) itself;
The special linear group SLn(K) (the subgroup of matrices with determinant 1);
The group of invertible upper (or lower) triangular matrices
If gi is a collection of elements in GLn(K) indexed by a set I, then the subgroup generated by the gi is a linear group.
In the study of Lie groups, it is sometimes pedagogically convenient to restrict attention to Lie groups that can be faithfully represented over the field of complex numbers. (Some authors require that the group be represented as a closed subgroup of the GLn(C).) Books that follow this approach include Hall (2015) and Rossmann (2002).
Classes of linear groups
Classical groups and related examples
The so-called classical groups generalize the examples 1 and 2 above. They arise as linear algebraic groups, that is, as subgroups of GLn defined by a finite number of equations.
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https://en.wikipedia.org/wiki/Belt%20of%20Venus
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The Belt of Venus (also called Venus's Girdle, the antitwilight arch, or antitwilight) is an atmospheric phenomenon visible shortly before sunrise or after sunset, during civil twilight. It is a pinkish glow that surrounds the observer, extending roughly 10–20° above the horizon. It appears opposite to the afterglow, which it also reflects.
In a way, the Belt of Venus is actually alpenglow visible near the horizon during twilight, above the antisolar point. Like alpenglow, the backscatter of reddened sunlight also creates the Belt of Venus. Though unlike alpenglow, the sunlight scattered by fine particulates that cause the rosy arch of the Belt shines high in the atmosphere and lasts for a while after sunset or before sunrise.
As twilight progresses, the arch is separated from the horizon by the dark band of Earth's shadow, or "twilight wedge". The pinkish glow is due to the Rayleigh scattering of light from the rising or setting Sun, which is then backscattered by particulates. A similar effect can be seen on a "blood moon" during a total lunar eclipse. The zodiacal light and gegenschein, which are caused by the diffuse reflection of sunlight from interplanetary dust in the Solar System, are also similar phenomena.
The Belt of Venus can be observed as having a vivider pink color during the winter months, as opposed to the summer months, when it appears faded and dim above the yellowish-orange band near the horizon.
The name of the phenomenon alludes to the cestus, a girdle or breast-band, of the Ancient Greek goddess Aphrodite, customarily equated with the Roman goddess Venus. Since the greatest elongation (angular separation between the Sun and a Solar System body) of Venus is only 45–48°, the inferior planet never appears in the opposite of the Sun's direction (180° difference in ecliptic longitude) from Earth and is thus never located in the Belt of Venus.
See also
Anticrepuscular rays
Atmospheric refraction
Blue hour
Earth's shadow
Golden hour or Magic hou
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https://en.wikipedia.org/wiki/Omega%20language
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In formal language theory within theoretical computer science, an infinite word is an infinite-length sequence (specifically, an ω-length sequence) of symbols, and an ω-language is a set of infinite words. Here, ω refers to the first ordinal number, the set of natural numbers.
Formal definition
Let Σ be a set of symbols (not necessarily finite). Following the standard definition from formal language theory, Σ* is the set of all finite words over Σ. Every finite word has a length, which is a natural number. Given a word w of length n, w can be viewed as a function from the set {0,1,...,n−1} → Σ, with the value at i giving the symbol at position i. The infinite words, or ω-words, can likewise be viewed as functions from to Σ. The set of all infinite words over Σ is denoted Σω. The set of all finite and infinite words over Σ is sometimes written Σ∞ or Σ≤ω.
Thus an ω-language L over Σ is a subset of Σω.
Operations
Some common operations defined on ω-languages are:
Intersection and union Given ω-languages L and M, both and are ω-languages.
Left concatenation Let L be an ω-language, and K be a language of finite words only. Then K can be concatenated on the left, and only on the left, to L to yield the new ω-language KL.
Omega (infinite iteration) As the notation hints, the operation is the infinite version of the Kleene star operator on finite-length languages. Given a formal language L, Lω is the ω-language of all infinite sequences of words from L; in the functional view, of all functions .
Prefixes Let w be an ω-word. Then the formal language Pref(w) contains every finite prefix of w.
Limit Given a finite-length language L, an ω-word w is in the limit of L if and only if is an infinite set. In other words, for an arbitrarily large natural number n, it is always possible to choose some word in L, whose length is greater than n, and which is a prefix of w. The limit operation on L can be written Lδ or .
Distance between ω-words
The set Σω can be m
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https://en.wikipedia.org/wiki/Ensonido
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Ensonido is a real-time post processing algorithm that allows users to play back MP3 Surround files in standard headphones.
Ensonido was developed by the Fraunhofer Society. It simulates the natural reception of surround sound by the human ear, which usually receives tones from surrounding loudspeakers and from reflections and echoes of the listening room. The out-of-head localization achieved that way increases the listening comfort noticeably in contrast to conventional stereo headphone listening with its in-head localization of all sounds. In version 3.0 of the Fraunhofer IIS MP3 Surround Player, Ensonido is replaced with newer mp3HD
External links
all4mp3.com Software, demos, information, and various mp3 resources
mp3surround.com - Demo content, information and evaluation software
The Register news story
Press Releases
mp3surrounded.com - First Blog in the internet about MP3 Surround-MP3 Surround Samples
Audio codecs
Digital audio
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https://en.wikipedia.org/wiki/Phrase%20completions
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Phrase completion scales are a type of psychometric scale used in questionnaires. Developed in response to the problems associated with Likert scales, Phrase completions are concise, unidimensional measures that tap ordinal level data in a manner that approximates interval level data.
Overview of the phrase completion method
Phrase completions consist of a phrase followed by an 11-point response key. The phrase introduces part of the concept. Marking a reply on the response key completes the concept. The response key represents the underlying theoretical continuum. Zero(0)indicates the absence of the construct. Ten(10)indicates the theorized maximum amount of the construct. Response keys are reversed on alternate items to mitigate response set bias.
Sample question using the phrase completion method
I am aware of the presence of God or the Divine
Never Continually
0 1 2 3 4 5 6 7 8 9 10
Scoring and analysis
After the questionnaire is completed the score on each item is summed together, to create a test score for the respondent. Hence, Phrase Completions, like Likert scales, are often considered to be summative scales.
Level of measurement
The response categories represent an ordinal level of measurement. Ordinal level data, however, varies in terms of how closely it approximates interval level data. By using a numerical continuum as the response key instead of sentiments that reflect intensity of agreement, respondents may be able to quantify their responses in more equal units.
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https://en.wikipedia.org/wiki/Tree%20alignment
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In computational phylogenetics, tree alignment is a computational problem concerned with producing multiple sequence alignments, or alignments of three or more sequences of DNA, RNA, or protein. Sequences are arranged into a phylogenetic tree, modeling the evolutionary relationships between species or taxa. The edit distances between sequences are calculated for each of the tree's internal vertices, such that the sum of all edit distances within the tree is minimized. Tree alignment can be accomplished using one of several algorithms with various trade-offs between manageable tree size and computational effort.
Definition
Input: A set of sequences, a phylogenetic tree leaf-labeled by and an edit distance function between sequences.
Output: A labeling of the internal vertices of such that is minimized, where is the edit distance between the endpoints of .
The task is NP-hard.
Background
Sequence alignment
In bioinformatics, the basic method of information processing is to contrast the sequence data. Biologists use it to discover the function, structure, and evolutionary information in biological sequences. The following analyses are based on the sequence assembly: the phylogenetic analysis, the haplotype comparison, and the prediction of RNA structure. Therefore, the efficiency of sequence alignment will directly affect the efficacy of solving these problems. In order to design a rational and efficient sequence alignment, the algorithm derivation becomes an important branch of research in the field of bioinformatics.
Generally, sequence alignment means constructing a string from two or more given strings with the greatest similarity by adding letters, deleting letters, or adding a space for each string. The multiple sequence alignment problem is generally based on pairwise sequence alignment and currently, for a pairwise sequence alignment problem, biologists can use a dynamic programming approach to obtain its optimal solution. However, the multiple se
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https://en.wikipedia.org/wiki/Sun-3
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Sun-3 is a series of UNIX computer workstations and servers produced by Sun Microsystems, launched on September 9, 1985. The Sun-3 series are VMEbus-based systems similar to some of the earlier Sun-2 series, but using the Motorola 68020 microprocessor, in combination with the Motorola 68881 floating-point co-processor (optional on the Sun 3/50) and a proprietary Sun MMU. Sun-3 systems were supported in SunOS versions 3.0 to 4.1.1_U1 and also have current support in NetBSD and Linux.
Sun-3 models
Models are listed in approximately chronological order.
{| class="wikitable"
!Model
!Codename
!CPU board
!CPU MHz
!Max. RAM
!Chassis
|-
| 3/75
| Carrera
| Sun 3004
| 16.67 MHz
| 8 MB
| 2-slot VME (desktop)
|-
| 3/140
| Carrera
| Sun 3004
| 16.67 MHz
| 16 MB
| 3-slot VME (desktop/side)
|-
| 3/160
| Carrera
| Sun 3004
| 16.67 MHz
| 16 MB
| 12-slot VME (deskside)
|-
| 3/180
| Carrera
| Sun 3004
| 16.67 MHz
| 16 MB
| 12-slot VME (rackmount)
|-
| 3/150
| Carrera
| Sun 3004
| 16.67 MHz
| 16 MB
| 6-slot VME (deskside)
|-
| 3/50
| Model 25
| —
| 15.7 MHz
| 4 MB
| "wide Pizza-box" desktop
|-
| 3/110
| Prism
| —
| 16.67 MHz
| 12 MB
| 3-slot VME (desktop/side)
|-
| 3/260
| Sirius
| Sun 3200
| 25 MHz (CPU), 20 MHz (FPU)
| 32 MB
| 12-slot VME (deskside)
|-
| 3/280
| Sirius
| Sun 3200
| 25 MHz (CPU), 20 MHz (FPU)
| 32 MB
| 12-slot VME (rackmount)
|-
| 3/60
| Ferrari
| —
| 20 MHz
| 24 MB
| "wide Pizza-box" desktop
|-
| 3/E
| Polaris
| Sun 3/E
| 20 MHz
| 16 MB
| none (6U VME board)
|}
(Max. RAM sizes may be greater when third-party memory boards are used.)
Keyboard
The Sun Type 3 keyboard is split into three blocks:
special keys
main block
numeric pad
It shipped with Sun-3 systems.
Sun-3x
In 1989, coincident with the launch of the SPARCstation 1, Sun launched three new Sun-3 models, the 3/80, 3/470 and 3/480. Unlike previous Sun-3s, these use a Motorola 68030 processor, 68882 floating-point unit, and the 68030's integral MMU. This 68030-based architecture is called
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https://en.wikipedia.org/wiki/Ripple%20%28electrical%29
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Ripple (specifically ripple voltage) in electronics is the residual periodic variation of the DC voltage within a power supply which has been derived from an alternating current (AC) source. This ripple is due to incomplete suppression of the alternating waveform after rectification. Ripple voltage originates as the output of a rectifier or from generation and commutation of DC power.
Ripple (specifically ripple current or surge current) may also refer to the pulsed current consumption of non-linear devices like capacitor-input rectifiers.
As well as these time-varying phenomena, there is a frequency domain ripple that arises in some classes of filter and other signal processing networks. In this case the periodic variation is a variation in the insertion loss of the network against increasing frequency. The variation may not be strictly linearly periodic. In this meaning also, ripple is usually to be considered an incidental effect, its existence being a compromise between the amount of ripple and other design parameters.
Ripple is wasted power, and has many undesirable effects in a DC circuit: it heats components, causes noise and distortion, and may cause digital circuits to operate improperly. Ripple may be reduced by an electronic filter, and eliminated by a voltage regulator.
Voltage ripple
A non-ideal DC voltage waveform can be viewed as a composite of a constant DC component (offset) with an alternating (AC) voltage—the ripple voltage—overlaid. The ripple component is often small in magnitude relative to the DC component, but in absolute terms, ripple (as in the case of HVDC transmission systems) may be thousands of volts. Ripple itself is a composite (non-sinusoidal) waveform consisting of harmonics of some fundamental frequency which is usually the original AC line frequency, but in the case of switched-mode power supplies, the fundamental frequency can be tens of kilohertz to megahertz. The characteristics and components of ripple depend on its so
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https://en.wikipedia.org/wiki/Broadcast%20Markup%20Language
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Broadcast Markup Language, or BML, is an XML-based standard developed by Japan's Association of Radio Industries and Businesses as a data broadcasting specification for digital television broadcasting. It is a data-transmission service allowing text to be displayed on a 1seg TV screen.
The text contains news, sports, weather forecasts, emergency warnings such as Earthquake Early Warning, etc. free of charge. It was finalized in 1999, becoming ARIB STD-B24 Data Coding and Transmission Specification for Digital Broadcasting.
The STD-B24 specification is derived from an early draft of XHTML 1.0 strict, which it extends and alters. Some subset of CSS 1 and 2 is supported, as well as ECMAScript.
Example BML header:
<?xml version="1.0" encoding="EUC-JP" ?>
<!DOCTYPE bml PUBLIC "+//ARIB STD-B24:1999//DTD BML Document//JA" "bml_1_0.dtd">
<?bml bml-version="1.0" ?>
Since version 1.0 in 1999, BML standard has gone through several revisions, and , it is on version 5.0. However, due to a large installed user base of receivers which only support the original 1.0 specification, broadcasters are not able to introduce new features defined in later revisions.
See also
ARIB STD B24 character set
Integrated Services Digital Broadcasting
1seg
Ginga (SBTVD Middleware)
Further reading
Broadcast Markup Language (BML) at OASIS
External links
Official changelog for ARIB STD-B24
STD-B24 and others, List of ARIB Standards in the Field of Broadcasting (ARIB)
Broadcast engineering
Digital television
High-definition television
Industry-specific XML-based standards
Interactive television
ISDB
Satellite television
Japanese inventions
Telecommunications-related introductions in 1999
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https://en.wikipedia.org/wiki/Wave%E2%80%93particle%20duality%20relation
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The wave–particle duality relation, often loosely referred to as the Englert–Greenberger–Yasin duality relation, or the Englert–Greenberger relation, relates the visibility, , of interference fringes with the definiteness, or distinguishability, , of the photons' paths in quantum optics. As an inequality:
Although it is treated as a single relation, it actually involves two separate relations, which mathematically look very similar. The first relation, derived by Greenberger and Yasin in 1988, is expressed as . It was later extended to, providing an equality for the case of pure quantum states by Jaeger, Shimony, and Vaidman in 1995. This relation involves correctly guessing which of the two paths the particle would have taken, based on the initial preparation. Here can be called the predictability. A year later Englert, in 1996, derived a related relation dealing with experimentally acquiring knowledge of the two paths using an apparatus, as opposed to predicting the path based on initial preparation. This relation is . Here is called the distinguishability.
The significance of the relations is that they express quantitatively the complementarity of wave and particle viewpoints in double-slit experiments. The complementarity principle in quantum mechanics, formulated by Niels Bohr, says that the wave and particle aspects of quantum objects cannot be observed at the same time. The wave–particle duality relations makes Bohr's statement more quantitative – an experiment can yield partial information about the wave and particle aspects of a photon simultaneously, but the more information a particular experiment gives about one, the less it will give about the other. The predictability which expresses the degree of probability with which path of the particle can be correctly guessed, and the distinguishability which is the degree to which one can experimentally acquire information about the path of the particle, are measures of the particle information, whil
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https://en.wikipedia.org/wiki/Cofunction
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In mathematics, a function f is cofunction of a function g if f(A) = g(B) whenever A and B are complementary angles (pairs that sum to one right angle). This definition typically applies to trigonometric functions. The prefix "co-" can be found already in Edmund Gunter's Canon triangulorum (1620).
For example, sine (Latin: sinus) and cosine (Latin: cosinus, sinus complementi) are cofunctions of each other (hence the "co" in "cosine"):
The same is true of secant (Latin: secans) and cosecant (Latin: cosecans, secans complementi) as well as of tangent (Latin: tangens) and cotangent (Latin: cotangens, tangens complementi):
These equations are also known as the cofunction identities.
This also holds true for the versine (versed sine, ver) and coversine (coversed sine, cvs), the vercosine (versed cosine, vcs) and covercosine (coversed cosine, cvc), the haversine (half-versed sine, hav) and hacoversine (half-coversed sine, hcv), the havercosine (half-versed cosine, hvc) and hacovercosine (half-coversed cosine, hcc), as well as the exsecant (external secant, exs) and excosecant (external cosecant, exc):
See also
Hyperbolic functions
Lemniscatic cosine
Jacobi elliptic cosine
Cologarithm
Covariance
List of trigonometric identities
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https://en.wikipedia.org/wiki/Unimate
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Unimate was the first industrial robot,
which worked on a General Motors assembly line at the Inland Fisher Guide Plant in Ewing Township, New Jersey, in 1961.
It was invented by George Devol in the 1950s using his original patent filed in 1954 and granted in 1961 (). The patent begins:
The present invention relates to the automatic operation of machinery, particularly the handling apparatus, and to automatic control apparatus suited for such machinery.
Devol, together with Joseph Engelberger, his business associate, started the world's first robot manufacturing company, Unimation.
The machine undertook the job of transporting die castings from an assembly line and welding these parts on auto bodies, a dangerous task for workers, who might be poisoned by toxic fumes or lose a limb if they were not careful.
The original Unimate consisted of a large computer-like box, joined to another box and was connected to an arm, with systematic tasks stored in a drum memory.
The Unimate also appeared on The Tonight Show hosted by Johnny Carson on which it knocked a golf ball into a cup, poured a beer, waved the orchestra conductor's baton and grasped an accordion and waved it around.
In 2003 the Unimate was inducted into the Robot Hall of Fame.
In popular culture
Fictional robots called Unimate, designed by the character Alan von Neumann, Jr., appeared in comic books from DC Comics.
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https://en.wikipedia.org/wiki/Intumescent
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An intumescent is a substance that swells as a result of heat exposure, leading to an increase in volume and decrease in density. Intumescence refers to the process of swelling. Intumescent materials are typically used in passive fire protection and require listing, approval, and compliance in their installed configurations in order to comply with the national building codes and laws.
The details for individual building parts are specified in technical standards which are compiled and published by national or international standardization bodies like the British Standards Institute (BSI), the German Institute for Standardization (DIN), the American Society for Testing and Materials (ASTM) or the International Organization for Standardization (ISO).
Intumescent coatings for steel constructions must be approved in standardized fire tests.
Types
Soft char
These intumescent materials produce a light char which is a poor conductor of heat, thus retarding heat transfer. Typically the light char consist of microporous carbonaceous foam formed by a chemical reaction of three main components: ammonium polyphosphate, pentaerythritol tetranitrate, and melamine. The reaction takes place in a matrix formed by the molten binder which is typically based on vinyl acetate copolymers or styrene acrylates.
Ablative coatings contain a significant amount of hydrates. When the hydrates are heated, they decompose, and water vapour is released, which has a cooling effect. Once the water is spent, the insulation characteristics of the char that remains can retard heat transfer through the fire stop assembly.
Soft char products are typically used in thin film intumescent materials for fireproofing protection of structural steel as well as in firestop pillows.
Hard char
Harder char is produced with sodium silicates and graphite. These products are suitable for use in plastic pipe firestops in which applications it is necessary to exert expansion pressure to fill the gap left in the mid
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https://en.wikipedia.org/wiki/Computational%20phylogenetics
|
Computational phylogenetics, phylogeny inference, or phylogenetic inference focuses on computational and optimization algorithms, heuristics, and approaches involved in phylogenetic analyses. The goal is to find a phylogenetic tree representing optimal evolutionary ancestry between a set of genes, species, or taxa. Maximum likelihood, parsimony, Bayesian, and minimum evolution are typical optimality criteria used to assess how well a phylogenetic tree topology describes the sequence data. Nearest Neighbour Interchange (NNI), Subtree Prune and Regraft (SPR), and Tree Bisection and Reconnection (TBR), known as tree rearrangements, are deterministic algorithms to search for optimal or the best phylogenetic tree. The space and the landscape of searching for the optimal phylogenetic tree is known as phylogeny search space.
Maximum Likelihood (also likelihood) optimality criterion is the process of finding the tree topology along with its branch lengths that provides the highest probability observing the sequence data, while parsimony optimality criterion is the fewest number of state-evolutionary changes required for a phylogenetic tree to explain the sequence data.
Traditional phylogenetics relies on morphological data obtained by measuring and quantifying the phenotypic properties of representative organisms, while the more recent field of molecular phylogenetics uses nucleotide sequences encoding genes or amino acid sequences encoding proteins as the basis for classification.
Many forms of molecular phylogenetics are closely related to and make extensive use of sequence alignment in constructing and refining phylogenetic trees, which are used to classify the evolutionary relationships between homologous genes represented in the genomes of divergent species. The phylogenetic trees constructed by computational methods are unlikely to perfectly reproduce the evolutionary tree that represents the historical relationships between the species being analyzed. The historic
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https://en.wikipedia.org/wiki/Strand%20jack
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A strand jack (also known as strandjack) is a jack used to lift very heavy (e.g. thousands of tons or more with multiple jacks) loads for construction and engineering purposes. Strandjacking was invented by VSL Australia's Patrick Kilkeary & Bruce Ramsay in 1969 for concrete post tensioning systems, and is now widely used for heavy lifting, to erect bridges, offshore structures, refineries, power stations, major buildings and other structures where the use of conventional cranes is either impractical or too expensive.
Use
Strand jacks can be used horizontally for pulling objects and structures, and are widely used in the oil and gas industry for skidded loadouts. Oil rigs of 38,000 t have been moved in this way from the place of construction on to a barge.
Since multiple jacks can be operated simultaneously by hydraulic controllers, they can be used in tandem to lift very large loads of thousands of tons. Tandem use of even two cranes is a very difficult operation.
How it works
A strand jack is a hollow hydraulic cylinder with a set of steel cables (the "strands") passing through the open centre, each one passing through two clamps - one mounted to either end of the cylinder.
The jack operates in the manner of a caterpillar's walk: climbing (or descending) along the strands by releasing the clamp at one end, expanding the cylinder, clamping there, releasing the trailing end, contracting, and clamping the trailing end before starting over again. The real significance of this device lies in the facility for precision control.
The expansion and contraction can be done at any speed, and paused at any location. Although a lone jack may lift only 1700 tons or so, there exist computer control systems that can operate 120 jacks simultaneously, offering fingertip feel movement control over extremely massive objects.
In construction
Strand jacking is a construction process whereby large pre-fabricated building sections are carefully lifted and precisely placed. Th
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https://en.wikipedia.org/wiki/Logical%20truth
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Logical truth is one of the most fundamental concepts in logic. Broadly speaking, a logical truth is a statement which is true regardless of the truth or falsity of its constituent propositions. In other words, a logical truth is a statement which is not only true, but one which is true under all interpretations of its logical components (other than its logical constants). Thus, logical truths such as "if p, then p" can be considered tautologies. Logical truths are thought to be the simplest case of statements which are analytically true (or in other words, true by definition). All of philosophical logic can be thought of as providing accounts of the nature of logical truth, as well as logical consequence.
Logical truths are generally considered to be necessarily true. This is to say that they are such that no situation could arise in which they could fail to be true. The view that logical statements are necessarily true is sometimes treated as equivalent to saying that logical truths are true in all possible worlds. However, the question of which statements are necessarily true remains the subject of continued debate.
Treating logical truths, analytic truths, and necessary truths as equivalent, logical truths can be contrasted with facts (which can also be called contingent claims or synthetic claims). Contingent truths are true in this world, but could have turned out otherwise (in other words, they are false in at least one possible world). Logically true propositions such as "If p and q, then p" and "All married people are married" are logical truths because they are true due to their internal structure and not because of any facts of the world (whereas "All married people are happy", even if it were true, could not be true solely in virtue of its logical structure).
Rationalist philosophers have suggested that the existence of logical truths cannot be explained by empiricism, because they hold that it is impossible to account for our knowledge of logical tru
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https://en.wikipedia.org/wiki/Treewidth
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In graph theory, the treewidth of an undirected graph is an integer number which specifies, informally, how far the graph is from being a tree. The smallest treewidth is 1; the graphs with treewidth 1 are exactly the trees and the forests. The graphs with treewidth at most 2 are the series–parallel graphs. The maximal graphs with treewidth exactly are called -trees, and the graphs with treewidth at most are called partial -trees. Many other well-studied graph families also have bounded treewidth.
Treewidth may be formally defined in several equivalent ways: in terms of the size of the largest vertex set in a tree decomposition of the graph, in terms of the size of the largest clique in a chordal completion of the graph, in terms of the maximum order of a haven describing a strategy for a pursuit–evasion game on the graph, or in terms of the maximum order of a bramble, a collection of connected subgraphs that all touch each other.
Treewidth is commonly used as a parameter in the parameterized complexity analysis of graph algorithms. Many algorithms that are NP-hard for general graphs, become easier when the treewidth is bounded by a constant.
The concept of treewidth was originally introduced by under the name of dimension. It was later rediscovered by , based on properties that it shares with a different graph parameter, the Hadwiger number. Later it was again rediscovered by and has since been studied by many other authors.
Definition
A tree decomposition of a graph is a tree with nodes , where each is a subset of , satisfying the following properties (the term node is used to refer to a vertex of to avoid confusion with vertices of ):
The union of all sets equals . That is, each graph vertex is contained in at least one tree node.
If and both contain a vertex , then all nodes of in the (unique) path between and contain as well. Equivalently, the tree nodes containing vertex form a connected subtree of .
For every edge in the graph, there
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https://en.wikipedia.org/wiki/Erector%20spinae%20muscles
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The erector spinae ( ) or spinal erectors is a set of muscles that straighten and rotate the back. The spinal erectors work together with the glutes (gluteus maximus, gluteus medius and gluteus minimus) to maintain stable posture standing or sitting.
Structure
The erector spinae is not just one muscle, but a group of muscles and tendons which run more or less the length of the spine on the left and the right, from the sacrum, or sacral region, and hips to the base of the skull. They are also known as the sacrospinalis group of muscles. These muscles lie on either side of the spinous processes of the vertebrae and extend throughout the lumbar, thoracic, and cervical regions. The erector spinae is covered in the lumbar and thoracic regions by the thoracolumbar fascia, and in the cervical region by the nuchal ligament.
This large muscular and tendinous mass varies in size and structure at different parts of the vertebral column. In the sacral region, it is narrow and pointed, and at its origin chiefly tendinous in structure. In the lumbar region, it is larger, and forms a thick fleshy mass. Further up, it is subdivided into three columns. They gradually diminish in size as they ascend to be inserted into the vertebrae and ribs.
The erector spinae is attached to the medial crest of the sacrum (a slightly raised feature of the sacrum closer towards the midline of the body as opposed to the "lateral" crest which is further away from the midline of the body), to the spinous processes of the lumbar, and the eleventh and twelfth thoracic vertebrae and the supraspinous ligament, to the back part of the inner lip of the iliac crests (the top border of the hips), and to the lateral crests of the sacrum, where it blends with the sacrotuberous and posterior sacroiliac ligaments.
Some of its fibers are continuous with the fibers of origin of the gluteus maximus.
The muscular fibers form a large fleshy mass that splits, in the upper lumbar region, into three columns, viz., a
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https://en.wikipedia.org/wiki/Book%20embedding
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In graph theory, a book embedding is a generalization of planar embedding of a graph to embeddings in a book, a collection of half-planes all having the same line as their boundary. Usually, the vertices of the graph are required to lie on this boundary line, called the spine, and the edges are required to stay within a single half-plane. The book thickness of a graph is the smallest possible number of half-planes for any book embedding of the graph. Book thickness is also called pagenumber, stacknumber or fixed outerthickness. Book embeddings have also been used to define several other graph invariants including the pagewidth and book crossing number.
Every graph with vertices has book thickness at most , and this formula gives the exact book thickness for complete graphs. The graphs with book thickness one are the outerplanar graphs. The graphs with book thickness at most two are the subhamiltonian graphs, which are always planar; more generally, every planar graph has book thickness at most four. All minor-closed graph families, and in particular the graphs with bounded treewidth or bounded genus, also have bounded book thickness. It is NP-hard to determine the exact book thickness of a given graph, with or without knowing a fixed vertex ordering along the spine of the book. Testing the existence of a three-page book embedding of a graph, given a fixed ordering of the vertices along the spine of the embedding, has unknown computational complexity: it is neither known to be solvable in polynomial time nor known to be NP-hard.
One of the original motivations for studying book embeddings involved applications in VLSI design, in which the vertices of a book embedding represent components of a circuit and the wires represent connections between them. Book embedding also has applications in graph drawing, where two of the standard visualization styles for graphs, arc diagrams and circular layouts, can be constructed using book embeddings.
In transportation planning
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https://en.wikipedia.org/wiki/Arrhenotoky
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Arrhenotoky (from Greek -τόκος -tókos "birth of -" + ἄρρην árrhēn "male person"), also known as arrhenotokous parthenogenesis, is a form of parthenogenesis in which unfertilized eggs develop into males. In most cases, parthenogenesis produces exclusively female offspring, hence the distinction.
The set of processes included under the term arrhenotoky depends on the author: arrhenotoky may be restricted to the production of males that are haploid (haplodiploidy); may include diploid males that permanently inactivate one set of chromosomes (parahaploidy); or may be used to cover all cases of males being produced by parthenogenesis (including such cases as aphids, where the males are XO diploids). The form of parthenogenesis in which females develop from unfertilized eggs is known as thelytoky; when both males and females develop from unfertilized eggs, the term "deuterotoky" is used.
In the most commonly used sense of the term, arrhenotoky is synonymous with haploid arrhenotoky or haplodiploidy: the production of haploid males from unfertilized eggs in insects having a haplodiploid sex-determination system. Males are produced parthenogenetically, while diploid females are usually produced biparentally from fertilized eggs. In a similar phenomenon, parthenogenetic diploid eggs develop into males by converting one set of their chromosomes to heterochromatin, thereby inactivating those chromosomes. This is referred to as diploid arrhenotoky or parahaploidy.
Arrhenotoky occurs in members of the insect order Hymenoptera (bees, ants, and wasps) and the Thysanoptera (thrips). The system also occurs sporadically in some spider mites, Hemiptera, Coleoptera (bark beetles), and rotifers.
See also
Apomixis
Genomic imprinting
Pseudo-arrhenotoky
Thelytoky
Notes
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https://en.wikipedia.org/wiki/Bochner%27s%20formula
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In mathematics, Bochner's formula is a statement relating harmonic functions on a Riemannian manifold to the Ricci curvature. The formula is named after the American mathematician Salomon Bochner.
Formal statement
If is a smooth function, then
,
where is the gradient of with respect to , is the Hessian of with respect to and is the Ricci curvature tensor. If is harmonic (i.e., , where is the Laplacian with respect to the metric ), Bochner's formula becomes
.
Bochner used this formula to prove the Bochner vanishing theorem.
As a corollary, if is a Riemannian manifold without boundary and is a smooth, compactly supported function, then
.
This immediately follows from the first identity, observing that the integral of the left-hand side vanishes (by the divergence theorem) and integrating by parts the first term on the right-hand side.
Variations and generalizations
Bochner identity
Weitzenböck identity
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https://en.wikipedia.org/wiki/Foramen%20rotundum
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The foramen rotundum is a circular hole in the sphenoid bone of the skull. It connects the middle cranial fossa and the pterygopalatine fossa. It allows for the passage of the maxillary nerve (V2), a branch of the trigeminal nerve.
Structure
The foramen rotundum is one of the several circular apertures (the foramina) located in the base of the skull, in the anterior and medial part of the sphenoid bone.
The mean area of the foramina rotunda is not considerable, which may suggest that they play a minor role in the dynamics of blood circulation in the venous system of the head.
Development
The foramen rotundum evolves in shape throughout the fetal period, and from birth to adolescence. It achieves a perfect ring-shaped formation in the fetus after the 4th fetal month. It is mostly oval-shaped in the fetal period, and round-shaped after birth (generally speaking). After birth, the rotundum is about 2.5 mm and in 15- to 17-year-olds about 3 mm in length. The average diameter of the foramen rotundum in adults is 3.55 mm.
Function
The foramen rotundum allows the passage of the maxillary nerve (V2), a branch of the trigeminal nerve. It also allows the passage of the artery of the foramen rotundum and an emissary vein.
History
Etymology
Foramen is the Latin term designating a hole-like opening. It derives from the Latin forare meaning to bore or perforate. Here, the opening is round as indicated by the Latin rotundum meaning round.
See also
Foramen ovale
Foramen spinosum
Foramina of skull
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https://en.wikipedia.org/wiki/Parallel%20SCSI
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Parallel SCSI (formally, SCSI Parallel Interface, or SPI) is the earliest of the interface implementations in the SCSI family. SPI is a parallel bus; there is one set of electrical connections stretching from one end of the SCSI bus to the other. A SCSI device attaches to the bus but does not interrupt it. Both ends of the bus must be terminated.
SCSI is a peer-to-peer peripheral interface. Every device attaches to the SCSI bus in a similar manner. Depending on the version, up to 8 or 16 devices can be attached to a single bus. There can be multiple hosts and multiple peripheral devices but there should be at least one host. The SCSI protocol defines communication from host to host, host to a peripheral device, and peripheral device to a peripheral device. The Symbios Logic 53C810 chip is an example of a PCI host interface that can act as a SCSI target.
SCSI-1 and SCSI-2 have the option of parity bit error checking. Starting with SCSI-U160 (part of SCSI-3) all commands and data are error checked by a cyclic redundancy check.
History
The first two formal SCSI standards, SCSI-1 and SCSI-2, described parallel SCSI. The SCSI-3 standard then split the framework into separate layers which allowed the introduction of other data interfaces beyond parallel SCSI. The original SCSI-1 version of the parallel bus was 8 bits wide (plus a ninth parity bit). The SCSI-2 standard allowed for faster operation (10 MHz) and wider buses (16-bit or 32-bit). The 16-bit option became the most popular.
At 10 MHz with a bus width of 16 bits it is possible to achieve a data rate of 20 MB/s. Subsequent extensions to the SCSI standard allowed for faster speeds: 20 MHz, 40 MHz, 80 MHz, 160 MHz and finally 320 MHz. At 320 MHz x 16 bits there is a theoretical maximum peak data rate of 640 MB/s.
Due to the technical constraints of a parallel bus system, SCSI has since evolved into faster serial interfaces, mainly Serial Attached SCSI and Fibre Channel. The iSCSI protocol doesn't describe
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https://en.wikipedia.org/wiki/The%20Music%20of%20the%20Primes
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The Music of the Primes (British subtitle: Why an Unsolved Problem in Mathematics Matters; American subtitle: Searching to Solve the Greatest Mystery in Mathematics) is a 2003 book by Marcus du Sautoy, a professor in mathematics at the University of Oxford, on the history of prime number theory. In particular he examines the Riemann hypothesis, the proof of which would revolutionize our understanding of prime numbers. He traces the prime number theorem back through history, highlighting the work of some of the greatest mathematical minds along the way.
The cover design for the hardback version of the book contains several pictorial depictions of prime numbers, such as the number 73 bus. It also has an image of a clock, referring to clock arithmetic, which is a significant theme in the text.
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https://en.wikipedia.org/wiki/Siegel%27s%20theorem%20on%20integral%20points
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In mathematics, Siegel's theorem on integral points states that for a smooth algebraic curve C of genus g defined over a number field K, presented in affine space in a given coordinate system, there are only finitely many points on C with coordinates in the ring of integers O of K, provided g > 0.
The theorem was first proved in 1929 by Carl Ludwig Siegel and was the first major result on Diophantine equations that depended only on the genus and not any special algebraic form of the equations. For g > 1 it was superseded by Faltings's theorem in 1983.
History
In 1929, Siegel proved the theorem by combining a version of the Thue–Siegel–Roth theorem, from diophantine approximation, with the Mordell–Weil theorem from diophantine geometry (required in Weil's version, to apply to the Jacobian variety of C).
In 2002, Umberto Zannier and Pietro Corvaja gave a new proof by using a new method based on the subspace theorem.
Effective versions
Siegel's result was ineffective (see effective results in number theory), since Thue's method in diophantine approximation also is ineffective in describing possible very good rational approximations to algebraic numbers. Effective results in some cases derive from Baker's method.
See also
Diophantine geometry
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https://en.wikipedia.org/wiki/Course-of-values%20recursion
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In computability theory, course-of-values recursion is a technique for defining number-theoretic functions by recursion. In a definition of a function f by course-of-values recursion, the value of f(n) is computed from the sequence .
The fact that such definitions can be converted into definitions using a simpler form of recursion is often used to prove that functions defined by course-of-values recursion are primitive recursive. Contrary to course-of-values recursion, in primitive recursion the computation of a value of a function requires only the previous value; for example, for a 1-ary primitive recursive function g the value of g(n+1) is computed only from g(n) and n.
Definition and examples
The factorial function n! is recursively defined by the rules
This recursion is a primitive recursion because it computes the next value (n+1)! of the function based on the value of n and the previous value n! of the function. On the other hand, the function Fib(n), which returns the nth Fibonacci number, is defined with the recursion equations
In order to compute Fib(n+2), the last two values of the Fib function are required. Finally, consider the function g defined with the recursion equations
To compute g(n+1) using these equations, all the previous values of g must be computed; no fixed finite number of previous values is sufficient in general for the computation of g. The functions Fib and g are examples of functions defined by course-of-values recursion.
In general, a function f is defined by course-of-values recursion if there is a fixed primitive recursive function h such that for all n,
where is a Gödel number encoding the indicated sequence.
In particular
provides the initial value of the recursion. The function h might test its first argument to provide explicit initial values, for instance for Fib one could use the function defined by
where s[i] denotes extraction of the element i from an encoded sequence s; this is easily seen to be a primitive
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https://en.wikipedia.org/wiki/Field%20goal%20percentage
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Field goal percentage in basketball is the ratio of field goals made to field goals attempted. Its abbreviation is FG%. Although three-point field goal percentage is often calculated separately, three-point field goals are included in the general field goal percentage. Instead of using scales of 0 to 100%, the scale .000 to 1.000 is commonly used. A higher field goal percentage denotes higher efficiency. In basketball, a FG% of .500 (50%) or above is considered a good percentage, although this criterion does not apply equally to all positions. Guards usually have lower FG% than forwards and centers. Field goal percentage does not completely tell the skill of a player, but a low field goal percentage can indicate a poor offensive player or a player who takes many difficult shots. In the NBA, center Shaquille O'Neal had a high career FG% (around .580) because he played near the basket making many high percentage layups and dunks. Guard Allen Iverson often had a low FG% (around .420) because he took the bulk of his team's shot attempts, even with high difficulty shots.
The NBA career record for field goal percentage is held by DeAndre Jordan at 0.673. Currently, the highest field goal percentage record for a single season is 0.742 by New York Knicks center Mitchell Robinson which was set during the abbreviated 2019–20 season. Before Mitchell Robinson, NBA Hall of Fame player Wilt Chamberlain held the record from 1971-1972 to 2019-2020 with a season high field goal percentage of 0.727.
Field goal percentages were substantially lower in the NBA until the mid-to-late 1960s. For this reason, many early NBA stars have low field goal percentages, such as Bob Cousy at .375, and George Mikan, Bob Pettit, and Bill Russell, whose career field goal percentages of .404, .436, and .440, respectively, are much lower than later post players.
Three-point field goal percentage is usually kept as additional statistics. Its abbreviation is 3FG%. A 3FG% of .400 and above is a very goo
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https://en.wikipedia.org/wiki/Stylomastoid%20artery
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The stylomastoid artery enters the stylomastoid foramen and supplies the tympanic cavity, the tympanic antrum and mastoid cells, and the semicircular canals. It is a branch of the posterior auricular artery, and thus part of the external carotid arterial system.
In the young subject a branch from this vessel forms, with the anterior tympanic artery from the internal maxillary, a vascular circle, which surrounds the tympanic membrane, and from which delicate vessels ramify on that membrane.
It anastomoses with the superficial petrosal branch of the middle meningeal artery by a twig which enters the hiatus canalis facialis.
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https://en.wikipedia.org/wiki/161%20%28number%29
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161 (one hundred [and] sixty-one) is the natural number following 160 and preceding 162.
In mathematics
161 is the sum of five consecutive prime numbers: 23, 29, 31, 37, and 41
161 is a hexagonal pyramidal number.
161 is a semiprime. Since its prime factors 7 and 23 are both Gaussian primes, 161 is a Blum integer.
161 is a palindromic number
is a commonly used rational approximation of the square root of 5 and is the closest fraction with denominator <300 to that number.
In the military
was a U.S. Navy Type T2 tanker during World War II
was a U.S. Navy during World War II
was a U.S. Navy Trefoil-class concrete barge during World War II
was a U.S. Navy during World War II
was a U.S. Navy during World War II
was a U.S. Navy during World War II
was a U.S. Navy wooden yacht during World War I
was a U.S. Navy during World War II
was a U.S. Navy Achomawi-class fleet ocean tug following World War II
was a U.S. Navy fourth-group S-class submarine between 1920 and 1931
is a fictional U.S. Navy diesel engine submarine featured in the 1996 film Down Periscope
The 161st Intelligence Squadron unit of the Kansas Air National Guard. Its parent unit is the 184th Intelligence Wing
In music
The Bose 161 Speaker System (2001)
The Kay K-161 ThinTwin guitar
In transportation
MTA Maryland commuter bus 161
New Jersey Bus Route 161
London Bus route 161
In other fields
161 is also:
The year AD 161 or 161 BC
161 AH is a year in the Islamic calendar that corresponds to 777 – 778 CE
161 Athor is an M-type Main belt asteroid
E.161 is an ITU-T assigns letters to the 12-key telephone keypad
Fiorina Fury 161 is a foundry facility and penal colony from the film Alien 3
161 is used by Anti Fascist Action as a code for AFA (A=1, F=6, by order of the alphabet), sometimes used in 161>88 (88 is code for Heil Hitler among neo-nazis, as H=8)
See also
Anti-Fascist Action
List of highways numbered 161
United Nations Security Council Resolution 161
Unite
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https://en.wikipedia.org/wiki/Flags%20depicting%20the%20Southern%20Cross
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The Southern Cross or Crux, a constellation visible in the Southern Hemisphere, is depicted on flags and coats of arms of various countries and sub-national entities. This star constellation is visible mostly in the southern hemisphere and it therefore symbolises the southern location of its users.
The term Southern Cross can also refer to the blue saltire as used in various flags of the Confederate States of America in the American Civil War.
This list is an incomplete list and some of the flags in this list might not have official status. Flag proportions may vary between the different flags, and sometimes even vary between different versions of the same flag.
National flags of countries in the Southern Hemisphere
Other flags of the Commonwealth of Australia
Other flags of the Federative Republic of Brazil
Other flags of the Realm of New Zealand
Other flags of Papua New Guinea
Other flags in South America
Other flags with the Southern Cross
See also
Nordic Cross Flag
Union Flag
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https://en.wikipedia.org/wiki/Stylomastoid%20foramen
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The stylomastoid foramen is a foramen between the styloid and mastoid processes of the temporal bone of the skull. It is the termination of the facial canal, and transmits the facial nerve, and stylomastoid artery. Facial nerve inflammation in the stylomastoid foramen may cause Bell's palsy.
Structure
The stylomastoid foramen is between the styloid and mastoid processes of the temporal bone. The average distance between the opening of the stylomastoid foramen and the styloid process is around 0.7 mm or 0.8 mm in adults, but may decrease to around 0.2 mm during aging.
The stylomastoid foramen transmits the facial nerve, and the stylomastoid artery. These 2 structures lie directly next to each other.
Clinical significance
Bell's palsy can result from inflammation of the facial nerve where it leaves the skull at the stylomastoid foramen. Patients with Bell's palsy appear with facial drooping on the affected side.
Additional images
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https://en.wikipedia.org/wiki/Madge%20Networks
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Madge Networks NV was a networking technology company founded by Robert Madge, and is best known for its work with Token Ring. It was a global leader and pioneer of high-speed networking solutions in the mid-1990s, and also made significant contributions to technologies such as Asynchronous Transfer Mode (ATM) and Ethernet.
The company filed for bankruptcy in April 2003. The operational business of the company is currently trading as Madge Ltd. in the UK. Under a deal with Network Technology PLC, the company acquired the rights and copyright to Madge's products, brand and website, as well as the remaining inventory. The assets will be absorbed by Network Technology PLC subsidiary Ringdale Limited, making them the world's largest supplier of Token Ring technology.
Technology development
Madge Networks was once one of the world's leading suppliers of networking hardware. Headquartered in Wexham, England, Madge Networks developed Token Ring, Ethernet, ATM, ISDN, and other products providing extensive networking solutions. The company's products ranged from ISA/PCI network adapters for personal computers to work group switching hubs, routers, and ISDN backbone carriers. Madge focus was to provide convergence solutions in Ethernet, Token Ring, ISDN, and the then emerging ATM networking technologies. In addition to its Wexham headquarters, Madge operated main offices in Eatontown, New Jersey and San Jose, California, as well as offices in more than 25 countries throughout the world.
Founded in 1986, Madge Networks was a pioneer in the networking market, the emergence of which went on to define internal and external communications among corporations in every industry. Madge Networks was one of the world's leading proponents of Token Ring technology, producing ISA, PCI, and PC card adapters, switches, stacks, and other devices required for its implementation of Token Ring technology.
In the late 1990s Madge Networks had taken a leading role in developing the standards
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https://en.wikipedia.org/wiki/Stringent%20response
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The stringent response, also called stringent control, is a stress response of bacteria and plant chloroplasts in reaction to amino-acid starvation, fatty acid limitation, iron limitation, heat shock and other stress conditions. The stringent response is signaled by the alarmone (p)ppGpp, and modulates transcription of up to 1/3 of all genes in the cell. This in turn causes the cell to divert resources away from growth and division and toward amino acid synthesis in order to promote survival until nutrient conditions improve.
Response
In Escherichia coli, (p)ppGpp production is mediated by the ribosomal protein L11 (rplK resp. relC) and the ribosome-associated (p)ppGpp synthetase I, RelA; deacylated tRNA bound in the ribosomal A-site is the primary induction signal. RelA converts GTP and ATP into pppGpp by adding the pyrophosphate from ATP onto the 3' carbon of the ribose in GTP, releasing AMP. pppGpp is converted to ppGpp by the gpp gene product, releasing Pi. ppGpp is converted to GDP by the spoT gene product, releasing pyrophosphate (PPi).
GDP is converted to GTP by the ndk gene product. Nucleoside triphosphate (NTP) provides the Pi, and is converted to Nucleoside diphosphate (NDP).
In other bacteria, the stringent response is mediated by a variety of RelA/SpoT Homologue (RSH) proteins, with some having only synthetic, or hydrolytic or both (Rel) activities.
During the stringent response, (p)ppGpp accumulation affects the resource-consuming cell processes replication, transcription, and translation. (p)ppGpp is thought to bind RNA polymerase and alter the transcriptional profile, decreasing the synthesis of translational machinery (such as rRNA and tRNA), and increasing the transcription of biosynthetic genes. Additionally, the initiation of new rounds of replication is inhibited and the cell cycle arrests until nutrient conditions improve. Translational GTPases involved in protein biosynthesis are also affected by ppGpp, with Initiation Factor 2 (IF2) being
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https://en.wikipedia.org/wiki/CPU%20modes
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CPU modes (also called processor modes, CPU states, CPU privilege levels and other names) are operating modes for the central processing unit of some computer architectures that place restrictions on the type and scope of operations that can be performed by certain processes being run by the CPU. This design allows the operating system to run with more privileges than application software.
Ideally, only highly trusted kernel code is allowed to execute in the unrestricted mode; everything else (including non-supervisory portions of the operating system) runs in a restricted mode and must use a system call (via interrupt) to request the kernel perform on its behalf any operation that could damage or compromise the system, making it impossible for untrusted programs to alter or damage other programs (or the computing system itself).
In practice, however, system calls take time and can hurt the performance of a computing system, so it is not uncommon for system designers to allow some time-critical software (especially device drivers) to run with full kernel privileges.
Multiple modes can be implemented—allowing a hypervisor to run multiple operating system supervisors beneath it, which is the basic design of many virtual machine systems available today.
Mode types
The unrestricted mode is often called kernel mode, but many other designations exist (master mode, supervisor mode, privileged mode, etc.). Restricted modes are usually referred to as user modes, but are also known by many other names (slave mode, problem state, etc.).
Kernel
In kernel mode, the CPU may perform any operation allowed by its architecture; any instruction may be executed, any I/O operation initiated, any area of memory accessed, and so on. In the other CPU modes, certain restrictions on CPU operations are enforced by the hardware. Typically, certain instructions are not permitted (especially those—including I/O operations—that could alter the global state of the machine), some memory are
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https://en.wikipedia.org/wiki/Eastern%20Agricultural%20Complex
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The Eastern Agricultural Complex in the woodlands of eastern North America was one of about 10 independent centers of plant domestication in the pre-historic world. Incipient agriculture dates back to about 5300 BCE. By about 1800 BCE the Native Americans of the woodlands were cultivating several species of food plants, thus beginning a transition from a hunter-gatherer economy to agriculture. After 200 BCE when maize from Mexico was introduced to the Eastern Woodlands, the Native Americans of the eastern United States and adjacent Canada slowly changed from growing local indigenous plants to a maize-based agricultural economy. The cultivation of local indigenous plants other than squash and sunflower declined and was eventually abandoned. The formerly domesticated plants returned to their wild forms.
The first four plants known to have been domesticated at the Riverton Site in Illinois in 1800 BCE were goosefoot (Chenopodium berlandieri), sunflower (Helianthus annuus var. macrocarpus), marsh elder (Iva annua var. macrocarpa), and squash (Cucurbita pepo ssp. ovifera). Several other species of plants were later domesticated.
Origin of name and concept
The term Eastern Agricultural Complex (EAC) was popularized by anthropologist Ralph Linton in the 1940s. Linton suggested that the Eastern Woodland tribes integrated maize cultivation from Mayans and Aztecs in Mexico into their own pre-existing agricultural subsistence practices. Ethnobotanists Volney H. Jones and Melvin R. Gilmore built upon Ralph Linton's understanding of Eastern Woodland agriculture with their work in cave and bluff dwellings in Kentucky and the Ozark Mountains in Arkansas. George Quimby also popularized the term "Eastern complex" in the 1940s. Authors Guy Gibbons and Kenneth Ames suggested that "indigenous seed crops" is a more appropriate term than "complex".
Until the 1970s and 1980s most archaeologists believed that agriculture by Eastern Woodland peoples had been imported from Mexico, along
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https://en.wikipedia.org/wiki/Boot%20ROM
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The boot ROM is a type of ROM that is used for booting a computer system. There are two types: a mask boot ROM that cannot be changed afterwards and a boot EEPROM, which can contain an UEFI implementation.
Purpose
Upon power up, hardware usually starts uninitialized. To continue booting, the system may need to read a bootloader from some peripheral device. It is often easier to implement routines for reading from external storage devices in software than in hardware. A boot ROM provides a place to store this initial loading code, at a fixed location immediately available to the processor when execution starts.
Operation
The boot ROM is mapped into memory at a fixed location, and the processor is designed to start executing from this location after reset. Usually, it is placed on the same die as the CPU, but it can also be an external ROM chip, as is common in older systems.
The boot ROM will then initialize the hardware busses and peripherals needed to boot. In some cases the boot ROM is capable of initializing RAM, and in other cases it is up to the bootloader to do that.
At the end of the hardware initialization, the boot ROM will try to load a bootloader from external peripheral(s) (like an eMMC, a microSD card, an external EEPROM, and so on) or through specific protocol(s) on a bus for data transmission (like USB, UART, etc).
In many systems on a chip, the peripherals or buses from which the boot ROM tries to load the bootloader (such as eMMC for embedded bootloader, or external EEPROM for UEFI implementation), and the order in which they are loaded, can be configured. This configuration can be done by blowing some electronic fuses inside the system on a chip to encode that information, or by having specific pins or jumpers of the system on a chip high or low.
Some boot ROMs are capable of checking the digital signature of the bootloader and will refuse to run the bootloader and stop the boot if the signature is not valid or has not been signed with an
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https://en.wikipedia.org/wiki/Zone%20valve
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A zone valve is a specific type of valve used to control the flow of water or steam in a hydronic heating or cooling system.
In the interest of improving efficiency and occupant comfort, such systems are commonly divided up into multiple zones. For example, in a house, the main floor may be served by one heating zone while the upstairs bedrooms are served by another. In this way, the heat can be directed principally to the main floor during the day and principally to the bedrooms at night, allowing the unoccupied areas to cool down.
This zoning can be accomplished in one of two ways:
Multiple circulator pumps, or
A single circulator pump and zone valves.
Zone valve construction and operation
Zone valves as used in home hydronic systems are usually electrically powered. In large commercial installations, vacuum or compressed air may be used instead. In either case, the motor is usually connected to the water valve via a mechanical coupling.
For electrical zone valves, the motor is often a small shaded-pole synchronous motor combined with a rotary switch that can disconnect the motor at either of the two stopping points ("valve open" or "valve closed"). In this way, applying power to the "open valve" terminal causes the motor to run until the valve is open while applying power at the "close valve" terminal causes the motor to run until the valve is closed. The motor is commonly powered from the same 24 volt ac power source that is used for the rest of the control system. This allows the zone valves to be directly controlled by low-voltage thermostats and wired with low-voltage wiring. This style of valve requires the use of an SPDT thermostat or relay.
A simpler variant of the motorized design omits the switch that detects the valve position. The motor is simply driven until the valve hits a mechanical stop, which stalls the motor. In an alternative design, the motor continues to turn, while a slip clutch allows the valve to be pushed against a mechanical stop
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https://en.wikipedia.org/wiki/Oldest%20people
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This is a list of tables of the oldest people in the world in ordinal ranks. To avoid including false or unconfirmed claims of old age, names here are restricted to those people whose ages have been validated by an international body dealing in longevity research, such as the Gerontology Research Group (GRG) or Guinness World Records (GWR), and others who have otherwise been reliably sourced.
The longest documented and verified human lifespan is that of Jeanne Calment of France (1875–1997), a woman who lived to age 122 years and 164 days. She claimed to have met Vincent van Gogh when she was 12 or 13. She received news media attention in 1985, after turning 110. Calment's claim was investigated and authenticated by Jean-Marie Robine and Dr Michel Allard for the GRG. Her longevity claim was put into question in 2018, but the original assessing team stood by their judgement.
As females live longer than males on average, women predominate in combined records. The longest lifespan for a man is that of Jiroemon Kimura of Japan (1897–2013), who lived to age 116 years and 54 days. The oldest living person in the world whose age has been validated is -year-old Maria Branyas of Spain, born 4 March 1907. The world's oldest known living man is -year-old Juan Vicente Pérez of Venezuela, born 27 May 1909. Academics have hypothesized the existence of a number of blue zones around the world where people live longer than average.
Ten oldest verified people ever
Systematic verification of longevity has only been practiced since the 1950s and only in certain parts of the world. All ten oldest verified people ever are female.
Oldest people (all women)
Oldest men
a Mortensen was born in Denmark.
b Kristal was born in Maleniec, Końskie County, then part of the Russian Empire, now in Poland.
Ten oldest living people
Oldest living people
c Branyas was born in the United States.
Oldest living men
Chronological list of the oldest known living person since 1954
This table l
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https://en.wikipedia.org/wiki/Argus%20%E2%80%93%20Audit%20Record%20Generation%20and%20Utilization%20System
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Argus – the Audit Record Generation and Utilization System is the first implementation of network flow monitoring, and is an ongoing open source network flow monitor project. Started by Carter Bullard in 1984 at Georgia Tech, and developed for cyber security at Carnegie Mellon University in the early 1990s, Argus has been an important contributor to Internet cyber security technology over its 30 years. .
The Argus Project is focused on developing all aspects of large scale network situational awareness and network audit trail establishment in support of Network Operations (NetOps), Performance and Security Management. Motivated by the telco Call detail record (CDR), Argus attempts to generate network metadata that can be used to perform a large number of network management tasks. Argus is used by many universities, corporations and government entities including US DISA, DoD, DHS, FFRDCs, GLORIAD and is a Top 100 Internet Security Tool. Argus is designed to be a real-time situational awareness system, and its data can be used to track, alarm and alert on wire-line network conditions. The data can also be used to establish a comprehensive audit of all network traffic, as described in the Red Book, US DoD NCSC-TG-005, supplementing traditional Intrusion detection system (IDS) based network security. The audit trail is traditionally used as historical network traffic measurement data for network forensics and Network Behavior Anomaly Detection (NBAD). Argus has been used extensively in cybersecurity, end-to-end performance analysis, and more recently, software-defined networking (SDN) research. Argus has also been a topic in network management standards development. RMON (1995) and IPFIX (2001).
Argus is composed of an advanced comprehensive network flow data generator, the Argus monitor, which processes packets (either capture files or live packet data) and generates detailed network traffic flow status reports of all the flows in the packet stream. Arg
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https://en.wikipedia.org/wiki/The%20Sacred%20Armour%20of%20Antiriad
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The Sacred Armour of Antiriad is an action-adventure game published by Palace Software in 1986 for Amstrad CPC, Commodore 64, DOS, TRS-80, and ZX Spectrum. In North America, the game was published by Epyx as Rad Warrior. The original game came with a 16-page comic book created by graphic artist Daniel Malone. The game is an early example of the Metroidvania genre, being developed without knowledge of and concurrently with Metroid.
Plot
In 2086, civilization destroys itself in a nuclear Armageddon, as two factions who both develop an anti-radiation battlesuit completely immune to conventional weapons go to war against each other when diplomatic peace talks break down. In the following millennia, the survivors develop into a hardy but peaceful race, living a quiet agricultural existence.
One day, mysterious alien forces emerge from an old volcano containing a pre-war military base and attack, quickly conquering and enslaving the new breed of humans, and forcing the populace to work in mines. Many rebel against the mysterious overlords and one of these rebels, Tal, is instructed by his elders to seek out a legendary armoured suit - the Sacred Armour of Antiriad (the last word being a corruption of "anti-radiation"), which is in fact one of the pre-war battlesuits whose development originally instigated the diplomatic crisis that started the nuclear war. This armour is rumoured to render the wearer impervious to attack and, with its help, Tal hopes to defeat and overthrow the alien rulers of Earth.
However, the armour requires other equipment to be added to it in order to make it function fully. These include anti-gravity boots, a particle negator, a pulsar beam, and an implosion mine. The last add-on is the most important as it is the one needed to destroy the volcano the enemy uses as its base.
Gameplay
The Sacred Armour of Antiriad is a mixture of a platform and maze game. The player controls Tal who, at the start, is simply a man dressed in a loincloth with t
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https://en.wikipedia.org/wiki/Garmin%20iQue
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iQue ( ; like "IQ") was a line of personal digital assistants (PDA) with integrated Global Positioning System (GPS) receivers sold by Garmin. It was introduced in 2003 and discontinued in mid-2008.
Description
The Garmin iQue 3600 was among the first devices to integrate GPS technology into a PDA. The line included devices running Palm OS and Windows Mobile operating systems. As of June 2008, all iQue products have been discontinued by Garmin and are no longer being supported or repaired by the company.
Integration of address book and date book with GPS location provides convenient ways for turn-by-turn voice guided navigation.
All devices include the Que software, including map display, auto-routing, search for points of interest and addresses in the map database, etc.
All devices have Wide Area Augmentation System (WAAS) and European Geostationary Navigation Overlay Service (EGNOS) abilities.
Popular accessories include external GPS antennas, vehicle mounts, power adaptors and external speakers.
Que software
The Que software provides integration (with address and datebook), navigation and mapping.
QueMap - map display
QueFind - search by various criteria through the database: address, points of interests, cities, services, facilities, etc.
QueGPS - satellite signal display
QueTracks - collects and manages GPS tracks
QueRoutes - routing and voice guidance preferences
QueTurns - turn by turn route guidance, used with automatic routing
QueTrip - statistics
List of products
Palm OS devices
iQue 3600 - Palm OS 5, 480x320 pixel display, voice recorder
iQue 3600a - Similar to an iQue 3600 but designed for aviation use
iQue 3200 - Palm OS 5, 320x320 pixel display, SDIO capable
iQue 3000 - Palm OS 5, 320x320 pixel display, with included 128 MB microSD card
Pocket PC devices
iQue M5 - Windows Mobile 2003 SE, 240x320 pixel display, SDIO/MMC compatible, Bluetooth
iQue M3 - Windows Mobile 2003 SE, 240x320 pixel display, SDIO compatible, 3D mapping
iQue M4 - Windo
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https://en.wikipedia.org/wiki/Network%20Computer%20Reference%20Profile
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Network Computer Reference Profile (NC reference profile, NCRP) was a specification for a network computer put forward by Oracle Corporation, endorsed by Sun Microsystems, IBM, Apple Computer, and Netscape, and finalized in 1996.
NC1
The first version of this specification was known as the NC1 Reference Profile.
NCRP specified minimum hardware requirements and software protocols. Among the software requirements were support of IP-based protocols (TCP/IP, FTP, etc.), www standards (HTTP, HTML, Java), email protocols, multimedia file formats, security standards. Operating systems used were NCOS or JavaOS.
The minimum hardware requirements were:
minimum screen resolution of 640 x 480 (VGA) or equivalent
pointing device
text input ability
audio output
Although this initial NC standard was intended to promote the diskless workstation model of computing, it did not preclude computers with additional features, such as the ability to operate either as a diskless workstation or a conventional fat client. Thus, an ordinary personal computer (PC) having all the required features, could technically be classified as a Network Computer; indeed, Sun noted that contemporary PCs did indeed meet the NC reference requirements.
StrongARM
The reference profile was subsequently revised to use the StrongARM processor.
Intel
After a trip by Ellison to Acer Group headquarters in 1996, he realised the importance to industry of having products based on Intel (x86-compatible) processors. NCI president Jerry Baker noted that "nobody [corporate users] had ever heard of the ARM chip".
Options
Many NCs operated via protocols such as BOOTP, DHCP, RARP and NFS.
Both for ISP-bound and LAN-based reference implementation NCs, a smartcard option was available. This allowed user authentication to be performed in a secure manner, with SSL providing transport security. The smartcard also provided minimal local storage for ISP dialup configuration settings. This configuration data was not
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https://en.wikipedia.org/wiki/Enclosure%20Services%20Interface
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The Enclosure Services Interface (ESI) is a computer protocol used in SCSI enclosures. This is part of a chain of connections that allows a host computer to communicate with the enclosure to access its power, cooling, and other non-data characteristics. This overall approach is called SCSI attached enclosure services:
The host computer communicates with the disks in the enclosure via a Serial SCSI interface (which may be either FC-AL or SAS). One of the disk devices located in the enclosure is set up to allow SCSI Enclosure Services (SES) communication through a LUN. The disk-drive then communicates with the SES processor in the enclosure via ESI. The data sent over the ESI interface is simply the contents of a SCSI command and the response to that command.
In fault-tolerant enclosures, more than one disk-drive slot has ESI enabled to allow SES communications to continue even after the failure of any of the disk-drives.
ESI electrical interface
The ESI interface was designed to make use of the seven existing "SEL_n" address signals which are used at power-on time for establishing the address (ALPA) of a disk-drive. An extra eighth signal called "-PARALLEL ESI" is used to switch the function of the SEL_n signals.
ESI command sequence
A SCSI Send Diagnostic command or Receive Diagnostic Results command is sent from the host computer to the disk-drive to initiate an SES transfer. The Disk-drive then asserts "-PARALLEL ESI" to begin this sequence of ESI bus phases:
Finally, the disk-drive deasserts "-PARALLEL ESI".
The above sequence is just a simple implementation of a 4-bit wide parallel interface which is used to execute a SCSI transaction. If the CDB is for a Send Diagnostic command then the data is sent to a SCSI diagnostic page in the enclosure. If the CDB is for a SCSI Receive Diagnostic Results command then the data is received from a SCSI diagnostic page. No other CDB types are allo
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https://en.wikipedia.org/wiki/Subcompact%20cardinal
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In mathematics, a subcompact cardinal is a certain kind of large cardinal number.
A cardinal number κ is subcompact if and only if for every A ⊂ H(κ+) there is a non-trivial elementary embedding j:(H(μ+), B) → (H(κ+), A) (where H(κ+) is the set of all sets of cardinality hereditarily less than κ+) with critical point μ and j(μ) = κ.
Analogously, κ is a quasicompact cardinal if and only if for every A ⊂ H(κ+) there is a non-trivial elementary embedding j:(H(κ+), A) → (H(μ+), B) with critical point κ and j(κ) = μ.
H(λ) consists of all sets whose transitive closure has cardinality less than λ.
Every quasicompact cardinal is subcompact. Quasicompactness is a strengthening of subcompactness in that it projects large cardinal properties upwards. The relationship is analogous to that of extendible versus supercompact cardinals. Quasicompactness may be viewed as a strengthened or "boldface" version of 1-extendibility. Existence of subcompact cardinals implies existence of many 1-extendible cardinals, and hence many superstrong cardinals. Existence of a 2κ-supercompact cardinal κ implies existence of many quasicompact cardinals.
Subcompact cardinals are noteworthy as the least large cardinals implying a failure of the square principle. If κ is subcompact, then the square principle fails at κ. Canonical inner models at the level of subcompact cardinals satisfy the square principle at all but subcompact cardinals. (Existence of such models has not yet been proved, but in any case the square principle can be forced for weaker cardinals.)
Quasicompactness is one of the strongest large cardinal properties that can be witnessed by current inner models that do not use long extenders. For current inner models, the elementary embeddings included are determined by their effect on P(κ) (as computed at the stage the embedding is included), where κ is the critical point. This prevents them from witnessing even a κ+ strongly compact cardinal κ.
Subcompact and quasicompact car
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https://en.wikipedia.org/wiki/Alt%20code
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On personal computers with numeric keypads that use Microsoft operating systems, such as Windows, many characters that do not have a dedicated key combination on the keyboard may nevertheless be entered using the Alt code (the Alt numpad input method). This is done by pressing and holding the key, then typing a number on the keyboard's numeric keypad that identifies the character and then releasing .
History and description
MS DOS
On IBM PC compatible personal computers from the 1980s, the BIOS allowed the user to hold down the key and type a decimal number on the keypad. It would place the corresponding code into the keyboard buffer so that it would look (almost) as if the code had been entered by a single keystroke. Applications reading keystrokes from the BIOS would behave according to what action they associate with that code. Some would interpret the code as a command, but often it would be interpreted as an 8-bit character from the current code page that was inserted into the text the user was typing. On the original IBM PC the code page was CP437.
Some Eastern European, Arabic and Asian computers used other hardware code pages, and MS-DOS was able to switch between them at runtime with commands like KEYB, CHCP or MODE. This causes the Alt combinations to produce different characters (as well as changing the display of any previously-entered text in the same manner). A common choice in locales using variants of the Latin alphabet was CP850, which provided more Latin character variants. (There were, however, many more code pages; for a more complete list, see code page).
PC keyboards designed for non-English use included other methods of inserting these characters, such as national keyboard layouts, the AltGr key or dead keys, but the Alt key was the only method of inserting some characters, and the only method that was the same on all machines, so it remained very popular. This input method is emulated by many pieces of software (such as later versions
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https://en.wikipedia.org/wiki/AMPRNet
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The AMPRNet (AMateur Packet Radio Network) or Network 44 is used in amateur radio for packet radio and digital communications between computer networks managed by amateur radio operators. Like other amateur radio frequency allocations, an IP range of was provided in 1981 for Amateur Radio Digital Communications (a generic term) and self-administered by radio amateurs. In 2001, undocumented and dual-use of as a network telescope began, recording the spread of the Code Red II worm in July 2001. In mid-2019, part of IPv4 range was sold off for conventional use, due to IPv4 address exhaustion.
Amateur Radio Digital Communications (mode)
Beginning on 1 May 1978, the Canadian authorities allowed radio amateurs on the 1.25-meter band (220 MHz) to use packet radio, and later in 1978 announced the "Amateur Digital Radio Operator's Certificate".
Discussion on digital communication amateur radio modes, using the Internet protocol suite and IPv4 addresses followed subsequently.
By 1988, one thousand assignments of address space had been made.
approximately 1% of inbound traffic volume to the network was legitimate radio amateur traffic that could be routed onwards, with the remaining 2‒100 gigabyte per day of Internet background noise being diverted and logged by the University of California San Diego (UCSD) internet telescope for research purposes.
By 2016, the European-based High-speed Amateur-radio Multimedia NETwork (HAMNET) offered a multi-megabit Internet Protocol network with 4,000 nodes, covering central Europe.
History and design
The use of the Internet protocols TCP/IP on amateur (ham) radio occurred early in Internet history, preceding the public Internet by over a decade. In 1981, Hank Magnuski obtained the class A netblock of 16.7 million IP addresses for amateur radio users worldwide. This was prior to Internet flag day (1 January 1983) when the ARPANET Network Control Protocol (NCP) was replaced by the Transmission Control Protocol (TCP). The initial
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https://en.wikipedia.org/wiki/Carrier-to-noise%20ratio
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In telecommunications, the carrier-to-noise ratio, often written CNR or C/N, is the signal-to-noise ratio (SNR) of a modulated signal. The term is used to distinguish the CNR of the radio frequency passband signal from the SNR of an analog base band message signal after demodulation. For example, with FM radio, the strength of the 100 MHz carrier with modulations would be considered for CNR, whereas the audio frequency analogue message signal would be for SNR; in each case, compared to the apparent noise. If this distinction is not necessary, the term SNR is often used instead of CNR, with the same definition.
Digitally modulated signals (e.g. QAM or PSK) are basically made of two CW carriers (the I and Q components, which are out-of-phase carriers). In fact, the information (bits or symbols) is carried by given combinations of phase and/or amplitude of the I and Q components. It is for this reason that, in the context of digital modulations, digitally modulated signals are usually referred to as carriers. Therefore, the term carrier-to-noise-ratio (CNR), instead of signal-to-noise-ratio (SNR), is preferred to express the signal quality when the signal has been digitally modulated.
High C/N ratios provide good quality of reception, for example low bit error rate (BER) of a digital message signal, or high SNR of an analog message signal.
Definition
The carrier-to-noise ratio is defined as the ratio of the received modulated carrier signal power C to the received noise power N after the receiver filters:
.
When both carrier and noise are measured across the same impedance, this ratio can equivalently be given as:
,
where and are the root mean square (RMS) voltage levels of the carrier signal and noise respectively.
C/N ratios are often specified in decibels (dB):
or in term of voltage:
Measurements and estimation
The C/N ratio is measured in a manner similar to the way the signal-to-noise ratio (S/N) is measured, and both specifications give an indication of
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https://en.wikipedia.org/wiki/Piecewise%20syndetic%20set
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In mathematics, piecewise syndeticity is a notion of largeness of subsets of the natural numbers.
A set is called piecewise syndetic if there exists a finite subset G of such that for every finite subset F of there exists an such that
where . Equivalently, S is piecewise syndetic if there is a constant b such that there are arbitrarily long intervals of where the gaps in S are bounded by b.
Properties
A set is piecewise syndetic if and only if it is the intersection of a syndetic set and a thick set.
If S is piecewise syndetic then S contains arbitrarily long arithmetic progressions.
A set S is piecewise syndetic if and only if there exists some ultrafilter U which contains S and U is in the smallest two-sided ideal of , the Stone–Čech compactification of the natural numbers.
Partition regularity: if is piecewise syndetic and , then for some , contains a piecewise syndetic set. (Brown, 1968)
If A and B are subsets of with positive upper Banach density, then is piecewise syndetic.
Other notions of largeness
There are many alternative definitions of largeness that also usefully distinguish subsets of natural numbers:
Cofiniteness
IP set
member of a nonprincipal ultrafilter
positive upper density
syndetic set
thick set
See also
Ergodic Ramsey theory
Notes
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https://en.wikipedia.org/wiki/Richard%20Klein%20%28paleoanthropologist%29
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Richard G. Klein (born April 11, 1941) is a Professor of Biology and Anthropology at Stanford University. He is the Anne T. and Robert M. Bass Professor in the School of Humanities and Sciences. He earned his PhD at the University of Chicago in 1966, and was elected to the National Academy of Sciences in April 2003. His research interests include paleoanthropology, Africa and Europe. His primary thesis is that modern humans evolved in East Africa, perhaps 100,000 years ago and, starting 50,000 years ago, began spreading throughout the non-African world, replacing archaic human populations over time. He is a critic of the idea that behavioral modernity arose gradually over the course of tens of thousands, hundreds of thousands of years or millions of years, instead supporting the view that modern behavior arose suddenly in the transition from the Middle Stone Age to the Later Stone Age around 50-40,000 years ago.
Early life and education
Klein was born in 1941 in Chicago, and went to college at the University of Michigan, Ann Arbor. In 1962, he enrolled as a graduate student at the University of Chicago to study with the Neanderthal expert, Francis Clark Howell. Of the two theories in vogue then, that Neanderthals had evolved into the Cro-Magnons of Europe or that they had been replaced by the Cro-Magnons, Klein favored the replacement theory. Klein completed a master's degree in 1964, and then studied at the University of Bordeaux with François Bordes, who specialized in prehistory. There he visited the La Quina and La Ferrassie caves in southwest France, containing Cro-Magnon artifacts layered on top of Neanderthal ones. These visits influenced him into believing the shift from Neanderthal to modern humans 40,000 to 35,000 years ago was sudden rather than gradual. Klein also visited Russia to examine artifacts.
Klein briefly held positions at the University of Wisconsin–Milwaukee, Northwestern University in Evanston, Illinois, and the University of Washington, S
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https://en.wikipedia.org/wiki/WDC%2065C21
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The W65C21S is a very flexible Peripheral Interface Adapter (PIA) for use with WDC’s 65xx and other 8-bit microprocessor families. It is produced by Western Design Center (WDC).
The W65C21S provides programmed microprocessor control of up to two peripheral devices (Port A and Port B). Peripheral device control is accomplished through two 8-bit bidirectional I/O Ports, with individually designed Data Direction Registers. The Data Direction Registers provide selection of data flow direction (input or output) at each respective I/O Port. Data flow direction may be selected on a line-by-line basis with intermixed input and output lines within the same port. The “handshake” interrupt control feature is provided by four peripheral control lines. This capability provides enhanced control over data transfer functions between the microprocessor and peripheral devices, as well as bidirectional data transfer between W65C21S Peripheral Interface Adapters in multiprocessor systems.
The PIA interfaces to the 65xx microprocessor family with a reset line, a ϕ2 clock line, a read/write line, two interrupt request lines, two register select lines, three chip select lines and an 8-bit bidirectional data bus. The PIA interfaces to the peripheral devices with four interrupt/control lines and two 8-bit bidirectional buses.
The W65C21S PIA is organized into two independent sections referred to as the A Side and the B Side. Each section consists of Control Register (CRA, CRB), Data Direction Register (DDRA, DDRB), Output Register (ORA, ORB), Interrupt Status Control (ISCA, ISCB) and the buffers necessary to drive the Peripheral Interface buses. Data Bus Buffers (DBB) interface data from the two sections to the data bus, while the Date Input Register (DIR) interfaces data from the DBB to the PIA registers. Chip Select and RWB control circuitry interface to the processor bus control lines.
Features of the W65C21S
Low power CMOS N-well silicon gate technology
High speed/Low power replace
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https://en.wikipedia.org/wiki/Vop%C4%9Bnka%27s%20principle
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In mathematics, Vopěnka's principle is a large cardinal axiom.
The intuition behind the axiom is that the set-theoretical universe is so large that in every proper class, some members are similar to others, with this similarity formalized through elementary embeddings.
Vopěnka's principle was first introduced by Petr Vopěnka and independently considered by H. Jerome Keisler, and was written up by .
According to , Vopěnka's principle was originally intended as a joke: Vopěnka was apparently unenthusiastic about large cardinals and introduced his principle as a bogus large cardinal property, planning to show later that it was not consistent. However, before publishing his inconsistency proof he found a flaw in it.
Definition
Vopěnka's principle asserts that for every proper class of binary relations (each with set-sized domain), there is one elementarily embeddable into another. This cannot be stated as a single sentence of ZFC as it involves a quantification over classes. A cardinal κ is called a Vopěnka cardinal if it is inaccessible and Vopěnka's principle holds in the rank Vκ (allowing arbitrary S ⊂ Vκ as "classes").
Many equivalent formulations are possible.
For example, Vopěnka's principle is equivalent to each of the following statements.
For every proper class of simple directed graphs, there are two members of the class with a homomorphism between them.
For any signature Σ and any proper class of Σ-structures, there are two members of the class with an elementary embedding between them.
For every predicate P and proper class S of ordinals, there is a non-trivial elementary embedding j:(Vκ, ∈, P) → (Vλ, ∈, P) for some κ and λ in S.
The category of ordinals cannot be fully embedded in the category of graphs.
Every subfunctor of an accessible functor is accessible.
(In a definable classes setting) For every natural number n, there exists a C(n)-extendible cardinal.
Strength
Even when restricted to predicates and proper classes definable in first o
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https://en.wikipedia.org/wiki/Hendrik%20Wade%20Bode
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Hendrik Wade Bode ( ; ; December 24, 1905 – June 21, 1982) was an American engineer, researcher, inventor, author and scientist, of Dutch ancestry. As a pioneer of modern control theory and electronic telecommunications he revolutionized both the content and methodology of his chosen fields of research. His synergy with Claude Shannon, the father of information theory, laid the foundations for the technological convergence of the information age.
He made important contributions to the design, guidance and control of anti-aircraft systems during World War II. He helped develop the automatic artillery weapons that defended London from the V-1 flying bombs during WWII. After the war, Bode along with his wartime rival Wernher von Braun, developer of the V-2 rocket, and, later, the father of the US space program, served as members of the National Advisory Committee for Aeronautics (NACA), the predecessor of NASA. During the Cold War, he contributed to the design and control of missiles and anti-ballistic missiles.
He also made important contributions to control systems theory and mathematical tools for the analysis of stability of linear systems, inventing Bode plots, gain margin and phase margin.
Bode was one of the great engineering philosophers of his era. Long respected in academic circles worldwide, he is also widely known to modern engineering students mainly for developing the asymptotic magnitude and phase plot that bears his name, the Bode plot.
His research contributions in particular were not only multidimensional but also far reaching, extending as far as the U.S. space program.
Education
Bode was born in Madison, Wisconsin. His father was a professor of education, and a faculty member at the University of Illinois at Urbana-Champaign by the time young Hendrik was ready for elementary school. He entered Leal Elementary School and rapidly advanced through the Urbana school system to graduate from high school at the age of 14.
Immediately after graduatio
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https://en.wikipedia.org/wiki/WDC%2065C22
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The W65C22 versatile interface adapter (VIA) is an input/output device for use with the 65xx series microprocessor family.
Overview
Designed by the Western Design Center, the W65C22 is made in two versions, both of which are rated for 14 megahertz operation, and available in DIP-40 or PLCC-44 packages.
W65C22N: This device is fully compatible with the NMOS 6522 produced by MOS Technology and others, and includes current-limiting resistors on its output lines. The W65C22N has an open-drain interrupt output (the pin) that is compatible with a wired-OR interrupt circuit. Hence the DIP-40 version is a "drop-in" replacement for the NMOS part.
W65C22S: This device is fully software– and partially hardware–compatible with the NMOS part. The W65C22S' output is a totem pole configuration, and thus cannot be directly connected to a wired-OR interrupt circuit.
As with the NMOS 6522, the W65C22 includes functions for programmed control of two peripheral ports (ports A and B). Two program–controlled 8-bit bi-directional peripheral I/O ports allow direct interfacing between the microprocessor and selected peripheral units. Each port has input data latching capability. Two programmable data direction registers (A and B) allow selection of data direction (input or output) on an individual I/O line basis.
Also provided are two programmable 16-bit interval timer/counters with latches. Timer 1 may be operated in a one-shot or free-run mode. In either mode, a timer can generate an interrupt when it has counted down to zero. Timer 2 functions as an interval counter or a pulse counter. If operating as an interval counter, timer 2 is driven by the microprocessor's PHI2 clock source. As a pulse counter, timer 2 is triggered by an external pulse source on the chip's line.
Serial data transfers are provided by a serial to parallel/parallel to serial shift register, with bit transfers synchronized with the PHI2 clock. Application versatility is further increased by various con
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https://en.wikipedia.org/wiki/WDC%2065C51
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The CMOS W65C51 Asynchronous Communications Interface Adapter (ACIA) provides an easily implemented, program controlled interface between microprocessor based systems and serial communication data sets and modems. It is produced by Western Design Center (WDC) and is a drop-in replacement for the MOS Technology 6551.
The ACIA has an internal baud rate generator, eliminating the need for multiple component support circuits. The transmitter rate can be selected under program control to be 1 of 15 different rates from 50 to 19,200 bits per second, or at 1/16 times an external clock rate. The receiver rate may be selected under program control to be either the Transmitter rate or at 1/16 times the external clock rate. The ACIA has programmable word lengths of 5, 6, 7 or 8 bits; even, odd or no parity 1, 1½ or 2 stop bits.
The ACIA is designed for maximum programmed control from the microprocessor (MPU) to simplify hardware implementation. Three separate registers permit an MPU to easily select the W65C51 operating modes, data checking parameters and determine operational status.
The command register controls parity, receiver echo mode, transmitter interrupt control, the state of the RTS line, receiver interrupt control and the state of the DTR line.
The control register controls the number of stop bits, the word length, receiver clock source and transmit/receive rate.
The status register indicates the status of the IRQ, DSR and DCD lines, transmitter and receiver data Registers, and overrun, framing and parity error conditions.
Transmitter and receiver data Registers are used for temporary data storage by the transmit and receiver circuits, each able to hold one byte.
Known bugs
The N version datasheet has a note regarding the Transmitter Data Register Empty flag:
"The W65C51N loads the Transmitter Data Register (TDR) and Transmitter Shift Register (TSR) at the same time. A delay should be used to insure that the shift register is empty before the TDR/TSR is rel
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https://en.wikipedia.org/wiki/Mercator%20series
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In mathematics, the Mercator series or Newton–Mercator series is the Taylor series for the natural logarithm:
In summation notation,
The series converges to the natural logarithm (shifted by 1) whenever .
History
The series was discovered independently by Johannes Hudde and Isaac Newton. It was first published by Nicholas Mercator, in his 1668 treatise Logarithmotechnia.
Derivation
The series can be obtained from Taylor's theorem, by inductively computing the nth derivative of at , starting with
Alternatively, one can start with the finite geometric series ()
which gives
It follows that
and by termwise integration,
If , the remainder term tends to 0 as .
This expression may be integrated iteratively k more times to yield
where
and
are polynomials in x.
Special cases
Setting in the Mercator series yields the alternating harmonic series
Complex series
The complex power series
is the Taylor series for , where log denotes the principal branch of the complex logarithm. This series converges precisely for all complex number . In fact, as seen by the ratio test, it has radius of convergence equal to 1, therefore converges absolutely on every disk B(0, r) with radius r < 1. Moreover, it converges uniformly on every nibbled disk , with δ > 0. This follows at once from the algebraic identity:
observing that the right-hand side is uniformly convergent on the whole closed unit disk.
See also
John Craig
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https://en.wikipedia.org/wiki/Fundamental%20unit%20%28number%20theory%29
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In algebraic number theory, a fundamental unit is a generator (modulo the roots of unity) for the unit group of the ring of integers of a number field, when that group has rank 1 (i.e. when the unit group modulo its torsion subgroup is infinite cyclic). Dirichlet's unit theorem shows that the unit group has rank 1 exactly when the number field is a real quadratic field, a complex cubic field, or a totally imaginary quartic field. When the unit group has rank ≥ 1, a basis of it modulo its torsion is called a fundamental system of units. Some authors use the term fundamental unit to mean any element of a fundamental system of units, not restricting to the case of rank 1 (e.g. ).
Real quadratic fields
For the real quadratic field (with d square-free), the fundamental unit ε is commonly normalized so that (as a real number). Then it is uniquely characterized as the minimal unit among those that are greater than 1. If Δ denotes the discriminant of K, then the fundamental unit is
where (a, b) is the smallest solution to
in positive integers. This equation is basically Pell's equation or the negative Pell equation and its solutions can be obtained similarly using the continued fraction expansion of .
Whether or not x2 − Δy2 = −4 has a solution determines whether or not the class group of K is the same as its narrow class group, or equivalently, whether or not there is a unit of norm −1 in K. This equation is known to have a solution if, and only if, the period of the continued fraction expansion of is odd. A simpler relation can be obtained using congruences: if Δ is divisible by a prime that is congruent to 3 modulo 4, then K does not have a unit of norm −1. However, the converse does not hold as shown by the example d = 34. In the early 1990s, Peter Stevenhagen proposed a probabilistic model that led him to a conjecture on how often the converse fails. Specifically, if D(X) is the number of real quadratic fields whose discriminant Δ < X is not divisible by a prime
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https://en.wikipedia.org/wiki/Spectro-temporal%20receptive%20field
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The spectro-temporal receptive field or spatio-temporal receptive field (STRF) of a neuron represents which types of stimuli excite or inhibit that neuron. "Spectro-temporal" refers most commonly to audition, where the neuron's response depends on frequency versus time, while "spatio-temporal" refers to vision, where the neuron's response depends on spatial location versus time. Thus they are not exactly the same concept, but both are referred to as STRF and serve a similar role in the analysis of neural responses.
If linearity is assumed, the neuron can be modeled as having a time-varying firing rate equal to the convolution of the stimulus with the STRF.
Auditory STRFs
The example STRF here is for an auditory neuron from the area CM (caudal medial) of a male zebra finch, when played conspecific birdsong. The colour of this plot shows the effect of sound on this neuron: this neuron tends to be excited by sound from about 2.5 kHz to 7 kHz heard by the animal 12 ms ago, but it is inhibited by sound in the same frequency range from about 18 ms ago.
Visual STRFs
See
Dario L. Ringach Receptive Fields in Macaque Primary Visual Cortex Spatial Structure and Symmetry of Simple-Cell (2002)
J. H. van Hateren and D. L. Ruderman Independent component analysis of natural image sequences yields spatio-temporal filters similar to simple cells in primary visual cortex (2002)
Idealized computational models for auditory receptive fields
A computational theory for early auditory receptive fields can be expressed from normative physical, mathematical and perceptual arguments, permitting axiomatic derivation of auditory receptive fields in two stages:
a first stage of temporal receptive fields corresponding to an idealized cochlea model modeled as window Fourier transform with either Gabor functions in the case of non-causal time or Gammatone functions alternatively generalized Gammatone functions for a truly time-causal model in which the future cannot be accessed,
a secon
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https://en.wikipedia.org/wiki/Flexor%20retinaculum%20of%20the%20hand
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The flexor retinaculum (transverse carpal ligament, or anterior annular ligament) is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel.
Structure
The flexor retinaculum is a strong, fibrous band that covers the carpal bones on the palmar side of the hand near the wrist. It attaches to the bones near the radius and ulna. On the ulnar side, the flexor retinaculum attaches to the pisiform bone and the hook of the hamate bone. On the radial side, it attaches to the tubercle of the scaphoid bone, and to the medial part of the palmar surface and the ridge of the trapezium bone.
The flexor retinaculum is continuous with the palmar carpal ligament, and deeper with the palmar aponeurosis. The ulnar artery and ulnar nerve, and the cutaneous branches of the median and ulnar nerves, pass on top of the flexor retinaculum. On the radial side of the retinaculum is the tendon of the flexor carpi radialis, which lies in the groove on the greater multangular between the attachments of the ligament to the bone.
The tendons of the palmaris longus and flexor carpi ulnaris are partly attached to the surface of the retinaculum; below, the short muscles of the thumb and little finger originate from the flexor retinaculum.
Function
The flexor retinaculum is the roof of the carpal tunnel, through which the median nerve and tendons of muscles which flex the hand pass.
Clinical significance
In carpal tunnel syndrome, one of the tendons or tissues in the carpal tunnel is inflamed, swollen, or fibrotic and puts pressure on the other structures in the tunnel, including the median nerve. Carpal tunnel syndrome is the most commonly reported nerve entrapment syndrome. It is often associated with repetitive motions of the wrist and fingers. It is because of this that pianists, meat cutters, and people with jobs involving extensive typing are at particularly high risk. The tough flexor retinacul
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