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https://en.wikipedia.org/wiki/PostBar
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PostBar, also known as CPC 4-State, is the black-ink barcode system used by Canada Post in its automated mail sorting and delivery operations. It is similar to other 4 State barcode systems used by Australia Post and the United Kingdom's Royal Mail (from which it derives), but uses an obscured structure and encoding system unique to Canada Post. This particular bar code system is used on "flats" (which are larger-than-letter-size pieces of mail, such as magazines) and parcels.
This symbology, derived from the RM4SCC system used by the British Royal Mail, uses a series of bars, each of which can individually have one of four possible states, to encode information used in automated sortation and delivery onto each piece of mail. Each bar can either be short and centred (known as a tracker), medium and elevated (an ascender), medium and lowered (a descender), or full height. This symbology also uses an element known as a Data Content Identifier (or DCI), which specifies what types of information are encoded into each barcode, such as postal codes, customer information, and exact delivery points. The information that goes into each barcode is obtained from the address printed on the front of the envelope it is ultimately printed on, as well as the physical dimensions of each piece of mail. This code also uses a Reed-Solomon error correction technique, so that in case a particular piece of mail is mishandled, the information encoded in the barcode can still be correctly decoded.
Character sets
Four character sets are used in PostBar codes, known as "A", "N", "Z" and "B" characters. Three-bar A characters are used exclusively to encode letters, and two-bar N characters encode only digits. Three-bar Z characters can encode either letters or digits. A and N characters are typically used to encode postal codes and country codes. Z characters are used for address locators, product types, and customer and service information. B characters are one bar each, and ar
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https://en.wikipedia.org/wiki/Vismon
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Vismon was the Bell Labs system which displayed authors' faces on one of their internal e-mail systems. The name was a pun on the sysmon program used at Bell to show the load on computer systems. It can also be interpreted as "visual monitor". The system inspired Rich Burridge to develop the similar but more widespread faces system, which spread with Unix distributions in the 1980s. This in turn inspired Steve Kinzler to develop the Picons, or personal icons, which have the goal of offering symbols and other images, as well as faces, to represent individuals and institutions in email messages. Other systems such as the faces available on the LAN email functions of the NeXTSTEP platform also seem to have been influenced by the original Vismon capabilities. The faces program in Plan 9 is the direct descendant of this system.
Vismon was the work of Rob Pike and Dave Presotto. It was based on some early experiments by Luca Cardelli. Many other scientists and engineers of the Computing Science Research Center of the Murray Hill facility were also involved. All had been spurred by the introduction in 1983 of the new Blit graphics terminal developed by Pike and Bart Locanthi and marketed by Teletype Corporation of Skokie, Illinois as the DMD 5620. Pike was eager, along with his colleagues, to exploit the new graphic capabilities.
Pike and company went around their Center, convincing everybody, from directors and administrative assistants to engineers and scientists, to pose as they got out a 4×5 view camera with a Polaroid back and took black-and-white photos (Polaroid type 52) of their faces. Their efforts yielded nearly 100 faces, which they digitised with a scanner from graphics colleagues. They wrote several programs to transform the faces, store them and serve them on several machines at the lab. As time went by, they added faces from outside their Center and outside Bell Labs. This database also led to the pico image editor (originally named zunk) which was
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https://en.wikipedia.org/wiki/IBM%20RT%20PC
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The IBM RT PC (RISC Technology Personal Computer) is a family of workstation computers from IBM introduced in 1986. These were the first commercial computers from IBM that were based on a reduced instruction set computer (RISC) architecture. The RT PC uses IBM's proprietary ROMP microprocessor, which commercialized technologies pioneered by IBM Research's 801 experimental minicomputer (the 801 was the first RISC). The RT PC runs three operating systems: AIX, the Academic Operating System (AOS), and Pick.
The RT PC's specifications were regarded as "less than impressive" compared to contemporary workstations by its competitors in that particular market, although the product was deemed deserving of "a healthy amount of respect", particularly with the prospect of IBM as "a serious competitor" who, despite having a product whose performance was an estimated 18 months behind other vendors, would potentially be able to catch up quickly by applying the company's renowned technological capabilities. Given such performance limitations, the RT PC had little commercial success as a result. IBM responded by introducing the RS/6000 workstations in 1990, which used a new IBM-proprietary RISC processor, the POWER1. All RT PC models were discontinued by May 1991.
Hardware
Two basic types were produced: a floor-standing desk-side tower, and a table-top desktop. Both types featured a special board slot for the processor card, as well as machine-specific RAM cards. Each machine had one processor slot, one co-processor slot, and two RAM slots.
There were three versions of the processor card:
The Standard Processor Card or 032 card had a 5.88MHz clock rate (170ns cycle time), 1MB of standard memory (expandable via 1, 2, or 4MB memory boards). It could be accompanied by an optional Floating-Point Accelerator (FPA) board, which contained a 10MHz National Semiconductor NS32081 floating point coprocessor. This processor card was used in the original RT PC models (010, 020, 025, and A2
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https://en.wikipedia.org/wiki/Elemental%20analysis
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Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each is present). Elemental analysis falls within the ambit of analytical chemistry, the instruments involved in deciphering the chemical nature of our world.
History
Antoine Lavoisier is regarded as the inventor of elemental analysis as a quantitative, experimental tool to assess the chemical composition of a compound. At the time, elemental analysis was based on the gravimetric determination of specific absorbent materials before and after selective adsorption of the combustion gases. Today fully automated systems based on thermal conductivity or infrared spectroscopy detection of the combustion gases, or other spectroscopic methods are used.
CHNX analysis
For organic chemists, elemental analysis or "EA" almost always refers to CHNX analysis—the determination of the mass fractions of carbon, hydrogen, nitrogen, and heteroatoms (X) (halogens, sulfur) of a sample. This information is important to help determine the structure of an unknown compound, as well as to help ascertain the structure and purity of a synthesized compound. In present-day organic chemistry, spectroscopic techniques (NMR, both 1H and 13C), mass spectrometry and chromatographic procedures have replaced EA as the primary technique for structural determination. However, it still gives very useful complementary information.
The most common form of elemental analysis, CHNS analysis, is accomplished by combustion analysis. Modern elemental analyzers are also capable of simultaneous determination of sulfur along with CHN in the same measurement run.
Quantitative analysis
Quantitative analysis determines the mass of each element or compound present. Other quanti
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https://en.wikipedia.org/wiki/Band%20sum
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In geometric topology, a band sum of two n-dimensional knots K1 and K2 along an (n + 1)-dimensional 1-handle h called a band is an n-dimensional knot K such that:
There is an (n + 1)-dimensional 1-handle h connected to (K1, K2) embedded in Sn+2.
There are points and such that is attached to along .
K is the n-dimensional knot obtained by this surgery.
A band sum is thus a generalization of the usual connected sum of knots.
See also
Manifold decomposition
References
.
.
Topology
Differential topology
Knot theory
Operations on structures
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https://en.wikipedia.org/wiki/Monitor%20%28synchronization%29
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In concurrent programming, a monitor is a synchronization construct that allows threads to have both mutual exclusion and the ability to wait (block) for a certain condition to become false. Monitors also have a mechanism for signaling other threads that their condition has been met. A monitor consists of a mutex (lock) object and condition variables. A condition variable is essentially a container of threads that are waiting for a certain condition. Monitors provide a mechanism for threads to temporarily give up exclusive access in order to wait for some condition to be met, before regaining exclusive access and resuming their task.
Another definition of monitor is a thread-safe class, object, or module that wraps around a mutex in order to safely allow access to a method or variable by more than one thread. The defining characteristic of a monitor is that its methods are executed with mutual exclusion: At each point in time, at most one thread may be executing any of its methods. By using one or more condition variables it can also provide the ability for threads to wait on a certain condition (thus using the above definition of a "monitor"). For the rest of this article, this sense of "monitor" will be referred to as a "thread-safe object/class/module".
Monitors were invented by Per Brinch Hansen and C. A. R. Hoare, and were first implemented in Brinch Hansen's Concurrent Pascal language.
Mutual exclusion
While a thread is executing a method of a thread-safe object, it is said to occupy the object, by holding its mutex (lock). Thread-safe objects are implemented to enforce that at each point in time, at most one thread may occupy the object. The lock, which is initially unlocked, is locked at the start of each public method, and is unlocked at each return from each public method.
Upon calling one of the methods, a thread must wait until no other thread is executing any of the thread-safe object's methods before starting execution of its method. Note
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https://en.wikipedia.org/wiki/Kismet%20%28software%29
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Kismet is a network detector, packet sniffer, and intrusion detection system for 802.11 wireless LANs. Kismet will work with any wireless card which supports raw monitoring mode, and can sniff 802.11a, 802.11b, 802.11g, and 802.11n traffic. The program runs under Linux, FreeBSD, NetBSD, OpenBSD, and macOS. The client can also run on Microsoft Windows, although, aside from external drones (see below), there's only one supported wireless hardware available as packet source.
Distributed under the GNU General Public License, Kismet is free software.
Features
Kismet differs from other wireless network detectors in working passively. Namely, without sending any loggable packets, it is able to detect the presence of both wireless access points and wireless clients, and to associate them with each other. It is also the most widely used and up to date open source wireless monitoring tool.
Kismet also includes basic wireless IDS features such as detecting active wireless sniffing programs including NetStumbler, as well as a number of wireless network attacks.
Kismet features the ability to log all sniffed packets and save them in a tcpdump/Wireshark or Airsnort compatible file format. Kismet can also capture "Per-Packet Information" headers.
Kismet also features the ability to detect default or "not configured" networks, probe requests, and determine what level of wireless encryption is used on a given access point.
In order to find as many networks as possible, Kismet supports channel hopping. This means that it constantly changes from channel to channel non-sequentially, in a user-defined sequence with a default value that leaves big holes between channels (for example, 1-6-11-2-7-12-3-8-13-4-9-14-5-10). The advantage with this method is that it will capture more packets because adjacent channels overlap.
Kismet also supports logging of the geographical coordinates of the network if the input from a GPS receiver is additionally available.
Server / Drone / Client
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https://en.wikipedia.org/wiki/Kronos%20%28computer%29
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Kronos is a series of 32-bit processor equipped printed circuit board systems, and the workstations based thereon, of a proprietary hardware architecture developed in the mid-1980s in Akademgorodok, a research city in Siberia, by the Academy of Sciences of the Soviet Union, Siberian branch, Novosibirsk Computing Center, Modular Asynchronous Developable Systems (MARS) project, Kronos Research Group (KRG).
History
In 1984, the Kronos Research Group (KRG) was founded by four students of the Novosibirsk State University, two from the mathematics department (Dmitry "Leo" Kuznetsov, Alex Nedoria) and two from the physics department (Eugene Tarasov, Vladimir Vasekin). At that time, the main objective was to build home computers for the KRG members.
In 1985, the group joined the Russian fifth generation computer project START, in which Kronos became a platform for developing multiprocessor reconfigurable Modular Asynchronous Developable Systems (MARS), and played a lead role in developing the first Russian full 32-bit workstation and its software.
During 7 years (1984–1991) the group designed and implemented:
Kronos 2.1 and 2.2 – 32-bit processor boards for DEC LSI-11
Kronos 2.5 – 32-bit processor board for Labtam computers
Kronos 2.6 – 32-bit workstation
The project START was finished in 1988. During the post-START years (1988–1991), several Russian industrial organizations expressed interest in continuing the Kronos development and some had been involved in facilitating the construction of Kronos and MARS prototypes, including the design of a Kronos-on-chip. However, changing funding levels and the chaotic economic situation during perestroika kept those plans from being realized.
Architecture
The Kronos instruction set architecture was based on Niklaus Wirth's Modula-2 workstation Lilith, developed at the Swiss Federal Institute of Technology (ETH Zurich) of Zurich Switzerland, which in turn was inspired by the Xerox Alto developed at Xerox PARC.
The Modula-2-b
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https://en.wikipedia.org/wiki/Type%20C%20videotape
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1–inch Type C (designated Type C by SMPTE) is a professional reel-to-reel analog recording helical scan videotape format co-developed and introduced by Ampex and Sony in 1976. It became the replacement in the professional video and broadcast television industries for the then-incumbent 2–inch quadruplex videotape (2–inch Quad for short) open-reel format. Additionally, it replaced the unsuccessful type A format, also invented by Ampex, and, primarily in mainland Europe, it supplemented the type B format, invented by the Fernseh division of Bosch, but it was replaced by type C format also there.
Technical detail
Compared to Quad, Type C had a smaller size, comparative ease of operation, and slightly higher video quality. 1–inch Type C is capable of "trick-play" functions such as still, shuttle, and variable-speed playback, including slow motion. 2–inch quadruplex videotape machines lacked these capabilities, due to the segmented manner in which it recorded video tracks onto the magnetic tape. 1–inch Type C VTRs required much less maintenance and used less power and space than did 2–inch machines.
1–inch Type C records composite video at a very high video quality that was superior to contemporary color-under formats such as U-matic, and of comparable quality to analog component video formats like Betacam and MII. Both analog component formats were notoriously fussy and trouble-prone, so in practice Type C gave a stable, more reliable picture than the broadcast quality analog cassette-based videotape formats. Because television was broadcast as a composite signal, there was no real downside to Type C in television broadcasting and distribution. It had approximately 300 (scan or vertical) lines of resolution, and a bandwidth of 5 MHz, with recording being done with the heads moving across the tape at (a writing speed of) 1,008 inches per second, or 25.59 meters per second for NTSC signals, and 21.39 meters per second for PAL signals. As for linear tape speeds, type C V
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https://en.wikipedia.org/wiki/Elias%20omega%20coding
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Elias ω coding or Elias omega coding is a universal code encoding the positive integers developed by Peter Elias. Like Elias gamma coding and Elias delta coding, it works by prefixing the positive integer with a representation of its order of magnitude in a universal code. Unlike those other two codes, however, Elias omega recursively encodes that prefix; thus, they are sometimes known as recursive Elias codes.
Omega coding is used in applications where the largest encoded value is not known ahead of time, or to compress data in which small values are much more frequent than large values.
To encode a positive integer N:
Place a "0" at the end of the code.
If N = 1, stop; encoding is complete.
Prepend the binary representation of N to the beginning of the code. This will be at least two bits, the first bit of which is a 1.
Let N equal the number of bits just prepended, minus one.
Return to Step 2 to prepend the encoding of the new N.
To decode an Elias omega-encoded positive integer:
Start with a variable N, set to a value of 1.
If the next bit is a "0" then stop. The decoded number is N.
If the next bit is a "1" then read it plus N more bits, and use that binary number as the new value of N. Go back to Step 2.
Examples
Omega codes can be thought of as a number of "groups". A group is either a single 0 bit, which terminates the code, or two or more bits beginning with 1, which is followed by another group.
The first few codes are shown below. Included is the so-called implied distribution, describing the distribution of values for which this coding yields a minimum-size code; see Relationship of universal codes to practical compression for details.
The encoding for 1 googol, 10100, is 11 1000 101001100 (15 bits of length header) followed by the 333-bit binary representation of 1 googol, which is 10010 01001001 10101101 00100101 10010100 11000011 01111100 11101011 00001011 00100111 10000100 11000100 11001110 00001011 11110011 10001010 11001110 01000000 1000111
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https://en.wikipedia.org/wiki/Bioenergetics
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Bioenergetics is a field in biochemistry and cell biology that concerns energy flow through living systems. This is an active area of biological research that includes the study of the transformation of energy in living organisms and the study of thousands of different cellular processes such as cellular respiration and the many other metabolic and enzymatic processes that lead to production and utilization of energy in forms such as adenosine triphosphate (ATP) molecules. That is, the goal of bioenergetics is to describe how living organisms acquire and transform energy in order to perform biological work. The study of metabolic pathways is thus essential to bioenergetics.
Overview
Bioenergetics is the part of biochemistry concerned with the energy involved in making and breaking of chemical bonds in the molecules found in biological organisms. It can also be defined as the study of energy relationships and energy transformations and transductions in living organisms. The ability to harness energy from a variety of metabolic pathways is a property of all living organisms. Growth, development, anabolism and catabolism are some of the central processes in the study of biological organisms, because the role of energy is fundamental to such biological processes. Life is dependent on energy transformations; living organisms survive because of exchange of energy between living tissues/ cells and the outside environment. Some organisms, such as autotrophs, can acquire energy from sunlight (through photosynthesis) without needing to consume nutrients and break them down. Other organisms, like heterotrophs, must intake nutrients from food to be able to sustain energy by breaking down chemical bonds in nutrients during metabolic processes such as glycolysis and the citric acid cycle. Importantly, as a direct consequence of the First Law of Thermodynamics, autotrophs and heterotrophs participate in a universal metabolic network—by eating autotrophs (plants), heterotrophs ha
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https://en.wikipedia.org/wiki/Matching%20pennies
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Matching pennies is the name for a simple game used in game theory. It is played between two players, Even and Odd. Each player has a penny and must secretly turn the penny to heads or tails. The players then reveal their choices simultaneously. If the pennies match (both heads or both tails), then Even keeps both pennies, so wins one from Odd (+1 for Even, −1 for Odd). If the pennies do not match (one heads and one tails) Odd keeps both pennies, so receives one from Even (−1 for Even, +1 for Odd).
Theory
Matching Pennies is a zero-sum game because each participant's gain or loss of utility is exactly balanced by the losses or gains of the utility of the other participants. If the participants' total gains are added up and their total losses subtracted, the sum will be zero.
The game can be written in a payoff matrix (pictured right - from Even's point of view). Each cell of the matrix shows the two players' payoffs, with Even's payoffs listed first.
Matching pennies is used primarily to illustrate the concept of mixed strategies and a mixed strategy Nash equilibrium.
This game has no pure strategy Nash equilibrium since there is no pure strategy (heads or tails) that is a best response to a best response. In other words, there is no pair of pure strategies such that neither player would want to switch if told what the other would do. Instead, the unique Nash equilibrium of this game is in mixed strategies: each player chooses heads or tails with equal probability. In this way, each player makes the other indifferent between choosing heads or tails, so neither player has an incentive to try another strategy. The best-response functions for mixed strategies are depicted in Figure 1 below:
When either player plays the equilibrium, everyone's expected payoff is zero.
Variants
Varying the payoffs in the matrix can change the equilibrium point. For example, in the table shown on the right, Even has a chance to win 7 if both he and Odd play Heads. To calcu
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https://en.wikipedia.org/wiki/Roundel
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A roundel is a circular disc used as a symbol. The term is used in heraldry, but also commonly used to refer to a type of national insignia used on military aircraft, generally circular in shape and usually comprising concentric rings of different colours. Other symbols also often use round shapes.
Heraldry
In heraldry, a roundel is a circular charge. Roundels are among the oldest charges used in coats of arms, dating from at least the twelfth century. Roundels in British heraldry have different names depending on their tincture. Thus, while a roundel may be blazoned by its tincture, e.g., a roundel vert (literally "a roundel green"), it is more often described by a single word, in this case pomme (literally "apple", from the French) or, from the same origins, pomeis—as in "Vert; on a cross Or five pomeis".
One special example of a named roundel is the fountain, depicted as a roundel barry wavy argent and azure, that is, containing alternating horizontal wavy bands of blue and silver (or white).
Military aircraft
The French Air Service originated the use of roundels on military aircraft during the First World War. The chosen design was the French national cockade, whose colours are the blue-white-red of the flag of France. Similar national cockades, with different ordering of colours, were designed and adopted as aircraft roundels by their allies, including the British Royal Flying Corps and Royal Naval Air Service, and (in the last few months of the war) the United States Army Air Service. After the First World War, many other air forces adopted roundel insignia, distinguished by different colours or numbers of concentric rings.
The term "roundel" is often used even for those military aircraft insignia that are not round, like the Iron Cross-Balkenkreuz symbol of the Luftwaffe or the red star of the Russian Air Force.
Flags
Among national flags which display a roundel are the flags of Bangladesh, Belize, Brazil, Dominica, Ethiopia, Grenada, India, Japan, La
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https://en.wikipedia.org/wiki/National%20Strategy%20to%20Secure%20Cyberspace
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In the United States government, the National Strategy to Secure Cyberspace, is a component of the larger National Strategy for Homeland Security. The National Strategy to Secure Cyberspace was drafted by the Department of Homeland Security in reaction to the September 11, 2001 terrorist attacks. Released on February 14, 2003, it offers suggestions, not mandates, to business, academic, and individual users of cyberspace to secure computer systems and networks. It was prepared after a year of research by businesses, universities, and government, and after five months of public comment. The plan advises a number of security practices as well as promotion of cyber security education.
The National Strategy to Secure Cyberspace identifies three strategic objectives: (1) Prevent cyber attacks against America's critical infrastructures; (2) Reduce national vulnerability to cyber attacks; and (3) Minimize damage and recovery time from cyber attacks that do occur. To meet these objectives, the National Strategy outlines five national priorities: The first priority, the creation of a National Cyberspace Security Response System, focuses on improving the government's response to cyberspace security incidents and reducing the potential damage from such events. The second, third, and fourth priorities (the development of a National Cyberspace Security Threat and Vulnerability Reduction Program, the creation of a National Cyberspace Security Awareness and Training Program, the necessity of Securing Governments' Cyberspace) aim to reduce threats from, and vulnerabilities to, cyber attacks. The fifth priority, the establishment of a system of National Security and International Cyberspace Security Cooperation, intends to prevent cyber attacks that could impact national security assets and to improve the international management of and response to such attacks.
Ultimately, the National Strategy encourages companies to regularly review their technology security plans, and individua
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https://en.wikipedia.org/wiki/SpySubtract
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SpySubtract was the name of an Anti-Spyware application for Microsoft Windows developed by InterMute. It was maintained by Trend Micro under the new name of Trend Micro Anti-Spyware, which came into effect from version 3.0. Previous versions did not have the Trend Micro branding.
Trend Micro Anti-Spyware was later discontinued on November 30, 2007, and replaced with Trend Micro AntiVirus plus AntiSpyware 2008.
The program is shareware, and was available to download as a 30-day trial.
Previously, SpySubtract was often pre-installed on new desktop and notebook computers.
References
Spyware removal
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https://en.wikipedia.org/wiki/Microsoft%20Defender%20Antivirus
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Microsoft Defender Antivirus (formerly Windows Defender) is an antivirus software component of Microsoft Windows. It was first released as a downloadable free anti-spyware program for Windows XP and was shipped with Windows Vista and Windows 7. It has evolved into a full antivirus program, replacing Microsoft Security Essentials in Windows 8 or later versions.
In March 2019, Microsoft announced Microsoft Defender ATP for Mac for business customers to protect their Mac devices from attacks on a corporate network, and a year later, to expand protection for mobile devices, it announced Microsoft Defender ATP for Android and iOS devices, which incorporates Microsoft SmartScreen, a firewall, and malware scanning. The mobile version of Microsoft Defender also includes a feature to block access to corporate data if it detects a malicious app is installed.
Microsoft Defender brand
As of 2021, Microsoft Defender Antivirus is part of the much larger Microsoft Defender brand, which includes several other software and service offerings, including:
Microsoft 365 Defender
Microsoft Defender for Cloud
Microsoft Defender Endpoint
Microsoft Defender for Office 365
Microsoft Defender for Identity
Microsoft Defender for Cloud Apps
Microsoft Defender Vulnerability Management
Microsoft Defender for Threat Intelligence
Microsoft Defender for Individuals
Features
Before Windows 8, Windows Defender only protected users against spyware. It includes a number of real-time security agents that monitor several common areas of Windows for changes which might have been caused by spyware. It also has the ability to remove installed ActiveX software. Windows Defender featured an integrated support for Microsoft SpyNet that allows users to report to Microsoft what they consider to be spyware, and what applications and device drivers they allow to be installed on their systems. Protection against viruses was subsequently added in Windows 8; which resembles Microsoft Security Essential
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https://en.wikipedia.org/wiki/Integrity%20%28operating%20system%29
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INTEGRITY and INTEGRITY-178B are real-time operating systems (RTOSes) produced and marketed by Green Hills Software.
INTEGRITY
INTEGRITY is POSIX-certified and intended for use in embedded systems of 32-bits or 64-bits. Supported computer architectures include variants of: ARM, Blackfin, ColdFire, MIPS, PowerPC, XScale, and x86. INTEGRITY is supported by popular SSL/TLS libraries such as wolfSSL.
INTEGRITY-178B
INTEGRITY-178B is the DO-178B–compliant version of INTEGRITY. It is used in several military jets such as the B-2, F-16, F-22, and F-35, and the commercial aircraft Airbus A380. Its kernel design guarantees bounded computing times by eliminating features such as dynamic memory allocation.
The auditing and security engineering abilities have allowed it to obtain the Evaluation Assurance Level (EAL) 6 rating by the National Security Agency (NSA). The Target of Evaluation (TOE) Architecture in the Security Target for the evaluation excludes components such as those for file system and networking, from the definition of the TOE, focusing almost solely on the core kernel. Other operating systems, such as Windows, macOS or Linux, though evaluated at lower levels of assurance, generally include these abilities within their TOE.
Supported processor architectures
The INTEGRITY Architecture Support Package (ASP) provides support for many processor families:
PowerPC/Power ISA
AMD and Intel: x86
ARM Holdings: ARM
MIPS
References
External links
INTEGRITY-178B
ARM operating systems
Embedded operating systems
Microkernel-based operating systems
Microkernels
MIPS operating systems
PowerPC operating systems
Proprietary operating systems
Real-time operating systems
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https://en.wikipedia.org/wiki/Medical%20slang
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Medical slang is the use of acronyms and informal terminology to describe patients, other healthcare personnel and medical concepts. Some terms are pejorative. In English, medical slang has entered popular culture via television hospital and forensic science dramas such as ER, House M.D., NCIS, Scrubs, and Grey's Anatomy, and through fiction, in books such as The House of GoId by Samuel Shem (Stephen Joseph Bergman), Bodies by Jed Mercurio, and A Case of Need by Jeffery Hudson (Michael Crichton)
Examples of pejorative language include bagged and tagged for a corpse, a reference to the intake process at a mortuary; donorcycle for motorcycle or PFO for pissed [drunk] and fell over. Less offensive are the terms blue pipes for veins; cabbage for a heart bypass (coronary artery bypass graft or CABG), and champagne tap for a flawless lumbar puncture, that is, one where erythrocyte count is zero.
Limitations on use
In many countries, facetious or insulting acronyms are now considered unethical and unacceptable, and patients can access their medical records. Medical facilities risk being sued by patients offended by the descriptions. Another reason for the decline is that facetious acronyms could be confused with genuine medical terms and the wrong treatment administered.
In one of his annual reports (related by the BBC), medical slang collector Adam Fox cited an example where a practitioner had entered “TTFO”, meaning “told to fuck off”, on a patient’s chart. When questioned about the chart entry, the practitioner said that the initials stood for “to take fluids orally.”
As a result, medical slang tends to be restricted to oral use and to informal notes or E-mails which do not form part of a patient’s formal records. It may also be used among medical staff outside of the hospital. It is not found on patients’ charts and, due to growing awareness of medical slang, often not used in front of patients themselves.
Non-English
Although online medical slang dictionaries a
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https://en.wikipedia.org/wiki/NIPRNet
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The Non-classified Internet Protocol (IP) Router Network (NIPRNet) is an IP network used to exchange unclassified information, including information subject to controls on distribution, among the private network's users. The NIPRNet also provides its users access to the Internet.
It is one of the United States Department of Defense's three main networks. The others include SIPRNet and JWICS.
History
NIPRNet is composed of Internet Protocol routers owned by the United States Department of Defense (DOD). It was created in the 1980s and managed by the Defense Information Systems Agency (DISA) to supersede the earlier MILNET.
Security improvements
In the year leading up to 2010 NIPRNet has grown faster than the U.S. Department of Defense can monitor. DoD spent $10 million in 2010 to map out the current state of the NIPRNet, in an effort to analyze its expansion, and identify unauthorized users, who are suspected to have quietly joined the network. The NIPRNet survey, which uses IPSonar software developed by Lumeta Corporation, also looked for weakness in security caused by network configuration. The Department of Defense has made a major effort in the year leading up to 2010, to improve network security. The Pentagon announced it was requesting $2.3 billion in the 2012 budget to bolster network security within the Defense Department and to strengthen ties with its counterparts at the Department of Homeland Security.
Alternative names
SIPRNet and NIPRNet are referred to colloquially as SIPPERnet and NIPPERnet (or simply sipper and nipper), respectively.
See also
Classified website
SIPRNet
RIPR
Joint Worldwide Intelligence Communications System (JWICS)
Intellipedia
Protective distribution system
NATO CRONOS
References
External links
DISA
Army and Defense Knowledge Online
Wide area networks
Cryptography
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https://en.wikipedia.org/wiki/JurisPedia
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JurisPedia is a wiki-based online encyclopedia of academic law in many languages, currently available in Arabic, Chinese, English, French, German, Spanish and Dutch. It was started in October 2004, inspired in part by Wikipedia and the Enciclopedia Libre (University of Seville). JurisPedia runs on the MediaWiki software, but it is not a Wikimedia Foundation project.
JurisPedia was developed on the initiative of the African Legal Information Institute, the Faculty of law of the Can Tho University (Vietnam), the team of JURIS (Université du Québec à Montréal, Canada), the of Saarland University (Germany), the Institut de Recherche et d'Études en Droit de l'Information et de la Communication (IREDIC) of Paul Cézanne University.
The site, one of the largest legal encyclopedias and online legal references, won the Dieter Meurer Prize for Legal Informatics for 2009.
Since 2012, JurisPedia is member of the Free Access to Law Movement.
On 10 March 2014, the French version of Jurispedia and the Bar Association of Paris have signed an agreement to take part in the creation of the "Great Library of Law".
See also
Comparative law wiki
List of online encyclopedias
References
External links
JurisPedia home page
Article about JurisPedia (United Nations Economic and Social Commission for Western Asia, World Summit on the Information Society).
Esther Hoorn, "Using the Wiki-Environment of Jurispedia in Legal Education , BILETA Annual Conference 2006 Malta, April 2006.
Creative Commons-licensed websites
MediaWiki websites
Wiki communities
Online encyclopedias
Encyclopedias of law
Free Access to Law Movement
Multilingual websites
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https://en.wikipedia.org/wiki/Diceware
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Diceware is a method for creating passphrases, passwords, and other cryptographic variables using ordinary dice as a hardware random number generator. For each word in the passphrase, five rolls of a six-sided die are required. The numbers from 1 to 6 that come up in the rolls are assembled as a five-digit number, e.g. 43146. That number is then used to look up a word in a cryptographic word list. In the original Diceware list 43146 corresponds to munch. By generating several words in sequence, a lengthy passphrase can thus be constructed randomly.
A Diceware word list is any list of unique words, preferably ones the user will find easy to spell and to remember. The contents of the word list do not have to be protected or concealed in any way, as the security of a Diceware passphrase is in the number of words selected, and the number of words each selected word could be taken from. Lists have been compiled for several languages, including Basque, Bulgarian, Catalan, Chinese, Czech, Danish, Dutch, English, Esperanto, Estonian, Finnish, French, German, Greek, Hebrew, Hungarian, Italian, Japanese, Latin, Māori, Norwegian, Polish, Portuguese, Romanian, Russian, Slovak, Slovenian, Spanish, Swedish and Turkish.
The level of unpredictability of a Diceware passphrase can be easily calculated: each word adds s of entropy to the passphrase (that is, bits). Originally, in 1995, Diceware creator Arnold Reinhold considered five words () the minimal length needed by average users. However, in 2014 Reinhold started recommending that at least six words () be used.
This level of unpredictability assumes that potential attackers know three things: that Diceware has been used to generate the passphrase, the particular word list used, and exactly how many words make up the passphrase. If the attacker has less information, the entropy can be greater than .
The above calculations of the Diceware algorithm's entropy assume that, as recommended by Diceware's author, each word is sepa
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https://en.wikipedia.org/wiki/Henry%20Kloss
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Henry Kloss (February 21, 1929 – January 31, 2002) was a prominent American audio engineer and entrepreneur who helped advance high fidelity loudspeaker and radio receiver technology beginning in the 1950s. Kloss (pronounced with a long o, like "close") was an undergraduate student in physics at the Massachusetts Institute of Technology (class of 1953), but never received a degree. He was responsible for a number of innovations, including, in part, the acoustic suspension loudspeaker and the high fidelity cassette deck. In 2000, Kloss was one of the first inductees into the Consumer Electronics Association's Hall of Fame. He earned an Emmy Award for his development of a projection television system, the Advent VideoBeam 1000.
Career
During the course of his half-century career, Kloss founded or co-founded several significant audio and video equipment manufacturing companies, most of which were located in Cambridge, Massachusetts, at least during the period he was directly associated with them.
After entering MIT in 1948, Kloss bought woodworking tools which he used to make enclosures for a speaker designed by an MIT professor and his student. Henry dropped out of MIT after being drafted. He was assigned to work in New Jersey, and took a night course in high fidelity taught by Edgar Villchur at New York University.
Kloss was an early adopter of new technology, including the transistor, Dolby noise reduction, and chromium dioxide magnetic recording tape.
Kloss Industries
In the early 1950s, Kloss built (but did not design) the Baruch-Lang speaker in his loft in Cambridge while he was a student at MIT. This corner speaker had four 5" drivers ("and 15 holes"), and sold for $25 (or $30 for the Deluxe Model "with a handsome frame and grill cloth").
Acoustic Research
Kloss co-founded Acoustic Research, Inc. (AR) with Edgar Villchur in the summer of 1954. Villchur, a former teacher of Kloss, had designed what he called the "acoustic suspension" loudspeaker, an elegant
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https://en.wikipedia.org/wiki/Amenable%20number
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An amenable number is a positive integer for which there exists a multiset of as many integers as the original number that both add up to the original number and when multiplied together give the original number. To put it algebraically, for a positive integer n, there is a multiset of n integers {a1, ..., an}, for which the equalities
hold. Negative numbers are allowed in the multiset. For example, 5 is amenable since 5 = 1 + (-1) + 1 + (-1) + 5. All and only those numbers congruent to 0 or 1 (mod 4), except 4, are amenable.
The first few amenable numbers are: 1, 5, 8, 9, 12, 13 ...
A solution for integers of the form n = 4k + 1 could be given by a set of 2k (+1)s and 2k (-1)s and n itself. (This generalizes the example of 5 given above.)
Although not obvious from the definition, the set of amenable numbers is closed under multiplication (the product of two amenable numbers is an amenable number).
All composite numbers would be amenable if the multiset was allowed to be of any length, because, even if other solutions are available, one can always obtain a solution by taking the prime factorization (expressed with repeated factors rather than exponents) and add as many 1s as necessary to add up to n. The product of this set of integers will yield n no matter how many 1s there are in the set. Furthermore, still under this assumption, any integer n would be amenable. Consider the inelegant solution for n of }. In the sum, the positive ones are cancelled out by the negative ones, leaving n, while in the product, the two negative ones cancel out the effect of their signs.
Amenable numbers should not be confused with amicable numbers, which are pairs of integers whose divisors add up to each other.
References
Mathworld entry on Amenable Numbers
Number theory
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https://en.wikipedia.org/wiki/Cole%20Prize
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The Frank Nelson Cole Prize, or Cole Prize for short, is one of twenty-two prizes awarded to mathematicians by the American Mathematical Society, one for an outstanding contribution to algebra, and the other for an outstanding contribution to number theory. The prize is named after Frank Nelson Cole, who served the Society for 25 years. The Cole Prize in algebra was funded by Cole himself, from funds given to him as a retirement gift; the prize fund was later augmented by his son, leading to the double award.
The prizes recognize a notable research work in algebra (given every three years) or number theory (given every three years) that has appeared in the last six years. The work must be published in a recognized, peer-reviewed venue.. The first award for algebra was made in 1928 to L. E. Dickson, while the first award for number theory was made in 1931 to H. S. Vandiver.
Frank Nelson Cole Prize in Algebra
Frank Nelson Cole Prize in Number Theory
For full citations, see external links.
See also
List of mathematics awards
References
External links
Frank Nelson Cole Prize in Algebra
Frank Nelson Cole Prize in Number Theory
Awards of the American Mathematical Society
Awards established in 1928
Triennial events
.
1928 establishments in the United States
Algebra
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https://en.wikipedia.org/wiki/Highly%20cototient%20number
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In number theory, a branch of mathematics, a highly cototient number is a positive integer which is above 1 and has more solutions to the equation
than any other integer below and above 1. Here, is Euler's totient function. There are infinitely many solutions to the equation for
= 1
so this value is excluded in the definition. The first few highly cototient numbers are:
2, 4, 8, 23, 35, 47, 59, 63, 83, 89, 113, 119, 167, 209, 269, 299, 329, 389, 419, 509, 629, 659, 779, 839, 1049, 1169, 1259, 1469, 1649, 1679, 1889, ...
Many of the highly cototient numbers are odd. In fact, after 8, all the numbers listed above are odd, and after 167 all the numbers listed above are congruent to 29 modulo 30.
The concept is somewhat analogous to that of highly composite numbers. Just as there are infinitely many highly composite numbers, there are also infinitely many highly cototient numbers. Computations become harder, since integer factorization becomes harder as the numbers get larger.
Example
The cototient of is defined as , i.e. the number of positive integers less than or equal to that have at least one prime factor in common with . For example, the cototient of 6 is 4 since these four positive integers have a prime factor in common with 6: 2, 3, 4, 6. The cototient of 8 is also 4, this time with these integers: 2, 4, 6, 8. There are exactly two numbers, 6 and 8, which have cototient 4. There are fewer numbers which have cototient 2 and cototient 3 (one number in each case), so 4 is a highly cototient number.
Primes
The first few highly cototient numbers which are primes are
2, 23, 47, 59, 83, 89, 113, 167, 269, 389, 419, 509, 659, 839, 1049, 1259, 1889, 2099, 2309, 2729, 3359, 3989, 4289, 4409, 5879, 6089, 6719, 9029, 9239, ...
See also
Highly totient number
References
Integer sequences
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https://en.wikipedia.org/wiki/Hydraulic%20machinery
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Hydraulic machines use liquid fluid power to perform work. Heavy construction vehicles are a common example. In this type of machine, hydraulic fluid is pumped to various hydraulic motors and hydraulic cylinders throughout the machine and becomes pressurized according to the resistance present. The fluid is controlled directly or automatically by control valves and distributed through hoses, tubes, or pipes.
Hydraulic systems, like pneumatic systems, are based on Pascal's law which states that any pressure applied to a fluid inside a closed system will transmit that pressure equally everywhere and in all directions. A hydraulic system uses an incompressible liquid as its fluid, rather than a compressible gas.
The popularity of hydraulic machinery is due to the very large amount of power that can be transferred through small tubes and flexible hoses, the high power density and a wide array of actuators that can make use of this power, and the huge multiplication of forces that can be achieved by applying pressures over relatively large areas. One drawback, compared to machines using gears and shafts, is that any transmission of power results in some losses due to resistance of fluid flow through the piping.
History
Joseph Bramah patented the hydraulic press in 1795. While working at Bramah's shop, Henry Maudslay suggested a cup leather packing. Because it produced superior results, the hydraulic press eventually displaced the steam hammer for metal forging.
To supply large-scale power that was impractical for individual steam engines, central station hydraulic systems were developed. Hydraulic power was used to operate cranes and other machinery in British ports and elsewhere in Europe. The largest hydraulic system was in London. Hydraulic power was used extensively in Bessemer steel production. Hydraulic power was also used for elevators, to operate canal locks and rotating sections of bridges. Some of these systems remained in use well into the twentieth centur
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https://en.wikipedia.org/wiki/Henry%20Petroski
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Henry Petroski (February 6, 1942 – June 14, 2023) was an American engineer specializing in failure analysis. A professor both of civil engineering and history at Duke University, he was also a prolific author. Petroski has written over a dozen books – beginning with To Engineer is Human: The Role of Failure in Successful Design (1985) and including a number of titles detailing the industrial design history of common, everyday objects, such as pencils, paper clips, toothpicks, and silverware. His first book was made into the film When Engineering Fails. He was a frequent lecturer and a columnist for the magazines American Scientist and Prism.
Life and education
Petroski was born in Brooklyn, New York, and was raised in Park Slope and Cambria Heights, Queens. In 1963, he received his bachelor's degree from Manhattan College. He graduated with his PhD in Theoretical and Applied Mechanics from the University of Illinois at Urbana-Champaign in 1968.
Career
Before beginning his work at Duke in 1980, Petroski worked at the University of Texas at Austin from 1968–74 and for the Argonne National Laboratory from 1975–80. Petroski was the Aleksandar S. Vesic Professor of Civil Engineering and a professor of history at Duke University.
In 2004, Petroski was appointed to the United States Nuclear Waste Technical Review Board and was reappointed in 2008.
Petroski had received honorary degrees from Clarkson University, Trinity College, Valparaiso University and Manhattan College. He was registered professional engineer in Texas, a Distinguished Member of the American Society of Civil Engineers, and a member of the American Academy of Arts and Sciences, the American Philosophical Society and the National Academy of Engineering.
Petroski was honored with the 2014 John P. McGovern Award for Science.
Petroski died from cancer in Durham, North Carolina on June 14, 2023, at the age of 81.
Published works
Books
To Engineer Is Human: The Role of Failure in Successful Design (1
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https://en.wikipedia.org/wiki/Discrete%20symmetry
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In mathematics and geometry, a discrete symmetry is a symmetry that describes non-continuous changes in a system. For example, a square possesses discrete rotational symmetry, as only rotations by multiples of right angles will preserve the square's original appearance. Discrete symmetries sometimes involve some type of 'swapping', these swaps usually being called reflections or interchanges. In mathematics and theoretical physics, a discrete symmetry is a symmetry under the transformations of a discrete group—e.g. a topological group with a discrete topology whose elements form a finite or a countable set.
One of the most prominent discrete symmetries in physics is parity symmetry. It manifests itself in various elementary physical quantum systems, such as quantum harmonic oscillator, electron orbitals of Hydrogen-like atoms by forcing wavefunctions to be even or odd. This in turn gives rise to selection rules that determine which transition lines are visible in atomic absorption spectra.
References
Slavik V. Jablan, Symmetry, Ornament and Modularity, Volume 30 of K & E Series on Knots and Everything, World Scientific, 2002.
Group theory
Theoretical physics
Symmetry
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https://en.wikipedia.org/wiki/Modular%20invariance
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In theoretical physics, modular invariance is the invariance under the group such as SL(2,Z) of large diffeomorphisms of the torus. The name comes from the classical name modular group of this group, as in modular form theory.
In string theory, modular invariance is an additional requirement for one-loop diagrams. This helps in getting rid of some global anomalies such as the gravitational anomalies.
Equivalently, in two-dimensional conformal field theory the torus partition function must be invariant under the modular group SL(2,Z).
String theory
Symmetry
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https://en.wikipedia.org/wiki/Soft%20SUSY%20breaking
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In theoretical physics, soft SUSY breaking is type of supersymmetry breaking that does not cause ultraviolet divergences to appear in scalar masses.
Overview
These terms are relevant operators—i.e. operators whose coefficients have a positive dimension of mass—though there are some exceptions.
A model with soft SUSY breaking was proposed in 1981 by Howard Georgi and Savas Dimopoulos. Before this, dynamical models of supersymmetry breaking were being used that suffered from giving rise to color and charge breaking vacua.
Soft SUSY breaking decouples the origin of supersymmetry breaking from its phenomenological consequences. In effect, soft SUSY breaking adds explicit symmetry breaking to the supersymmetric Standard Model Lagrangian. The source of SUSY breaking results from a different sector where supersymmetry is broken spontaneously. Divorcing the spontaneous supersymmetry breaking from the supersymmetric Standard Model leads to the notion of mediated supersymmetry breaking.
Example operators
Gaugino mass
Scalar masses
Scalar trilinear interactions ("A-terms")
Nonholomorphic soft supersymmetry breaking interactions
In low energy supersymmetry based models, the soft supersymmetry breaking interactions excepting the mass terms are usually considered to be holomorphic functions of fields. While a superpotential such as that of MSSM needs to be holomorphic, there is no reason why soft supersymmetry breaking interactions are required to be holomorphic functions of fields. Of course, an arbitrary nonholomorphic interaction may invite an appearance of quadratic divergence (or hard supersymmetry breaking); however, there are scenarios with no gauge singlet fields where nonholomorphic interactions can as well be of soft supersymmetry breaking type. One may consider a hidden sector based supersymmetry breaking, with and to be chiral superfields. Then, there exist nonholomorphic -term contributions of the forms that are soft supersymmetry breaking in na
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https://en.wikipedia.org/wiki/Shenzhen%20Metro
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The Shenzhen Metro () is the rapid transit system for the city of Shenzhen in Guangdong province, China. Extensions opened on 28 December 2022 put the network at of trackage, operating on 16 lines with 369 stations.
Shenzhen Metro is the 4th longest metro system in China and 4th longest in the world as of that date despite having only opened on 28 December 2004. By 2035 the network is planned to comprise 8 express and 24 non-express lines totaling of trackage.
Current system
Currently the network has of route, operating on 16 lines with 369 stations. Line 1, Line 4 and Line 10 run to the border crossings between the Shenzhen Special Economic Zone and the Hong Kong Special Administrative Region at Luohu/Lo Wu and Futian Checkpoint/Lok Ma Chau, where riders can transfer to Hong Kong's MTR East Rail line for travel onwards to Hong Kong.
Line 1
Line 1, formerly known as Luobao line, runs westward from Luohu to Airport East. Trains operate every 2 minutes during peak hours and every 4 minutes at other times. The line is operated by SZMC (Shenzhen Metro Group). Line 1's color is green.
28 December 2004: Luohu – Window of the World
28 September 2009: Window of the World – Shenzhen University
15 June 2011: Shenzhen University – Airport East
Line 2
Line 2, formerly known as Shekou line, runs from Chiwan to Liantang. Line 2 is connected with Line 8 at Liantang station. The line is operated by SZMC (Shenzhen Metro Group). Line 2's color is orange, the same as Line 8.
28 December 2010: Chiwan – Window of the World
28 June 2011: Window of the World – Xinxiu
28 October 2020: Xinxiu – Liantang
Line 3
Line 3, formerly known as Longgang line, runs from Futian Bonded Area to Shuanlong in Longgang, in the north-east part of the city. Construction began on 26 December 2005. The line is operated by Shenzhen Metro Line 3 Operations, which has been a subsidiary of SZMC (Shenzhen Metro Group) since 11 April 2011 when an 80% stake was transferred to SZMC. Line 3's color
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https://en.wikipedia.org/wiki/Arbuscular%20mycorrhiza
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An arbuscular mycorrhiza (AM) (plural mycorrhizae) is a type of mycorrhiza in which the symbiont fungus (AM fungi, or AMF) penetrates the cortical cells of the roots of a vascular plant forming arbuscules. Arbuscular mycorrhiza is a type of endomycorrhiza along with ericoid mycorrhiza and orchid mycorrhiza (not to be confused with ectomycorrhiza).
Arbuscular mycorrhizae are characterized by the formation of unique tree-like structures, the arbuscules. In addition, globular storage structures called vesicles are often encountered. Arbuscular mycorrhizae are formed by Glomeromycota and Mucoromycota fungi, sister clades of the more well-known and diverse dikaryan fungi (all three are together called "symbiomycota"). AM fungi help plants to capture nutrients such as phosphorus, sulfur, nitrogen and micronutrients from the soil. It is believed that the development of the arbuscular mycorrhizal symbiosis played a crucial role in the initial colonisation of land by plants and in the evolution of the vascular plants.
It has been said that it is quicker to list the plants that do not form endomycorrhizae than those that do. This symbiosis is a highly evolved mutualistic relationship found between fungi and plants, the most prevalent plant symbiosis known, and AMF is found in 80% of vascular plant families in existence today.
Previously this type of mycorrhizal associations were called 'Vesicular arbuscular mycorrhiza (VAM)', but since some members of these fungi do not produce any vesicles, such as the members of Gigasporaceae; the term has been changed to 'Arbuscular Mycorrhizae' to include them.
Advances in research on mycorrhizal physiology and ecology since the 1970s have led to a greater understanding of the multiple roles of AMF in the ecosystem. An example is the important contribution of the glue-like protein glomalin to soil structure (see below). This knowledge is applicable to human endeavors of ecosystem management, ecosystem restoration, and agriculture.
E
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https://en.wikipedia.org/wiki/Liquid%20smoke
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Liquid smoke is a water-soluble yellow to red liquid used as a flavoring as a substitute for cooking with wood smoke while retaining a similar flavor. It can be used to flavor any meat or vegetable. It is available as pure condensed smoke from various types of wood, and as derivative formulas containing additives.
History
Pyrolysis or thermal decomposition of wood in a low oxygen manner originated prehistorically to produce charcoal. Condensates of the vapors eventually were made and found useful as preservatives. For centuries, water-based condensates of wood smoke were popularly called "wood vinegar", presumably due to its use as food vinegar. Pliny the Elder recorded in one of his ten volumes of Natural History the use of wood vinegar as an embalming agent, declaring it superior to other treatments he used. In 1658, Johann Rudolf Glauber outlined the methods to produce wood vinegar during charcoal making. Further, he described the use of the water insoluble tar fraction as a wood preservative and documented the freezing of the wood vinegar to concentrate it. Use of the term "pyroligneous acid" for wood vinegar emerged by 1788.
In the United States, in 1895, E. H. Wright inaugurated the era of commercial distribution of pyroligneous acid under a new name, liquid smoke. Among Wright's innovations were the standardization of the product, marketing and distribution. Wright's Liquid Smoke, since 1997 owned by B&G Foods, and its modern-day successors have always been the subject of controversy about their contents and production, but in 1913, Wright prevailed in a federal misbranding case. Case judge Van Valkenburg wrote:
Historically, all pyroligneous acid products, Wright's product and many other condensates have been made as byproducts of charcoal manufacturing, which was of greater value. Chemicals such as methanol, acetic acid and acetone have been isolated from these condensates and sold. With the advent of lower cost fossil fuel sources, today these and othe
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https://en.wikipedia.org/wiki/Continuous%20automaton
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A continuous automaton can be described as a cellular automaton extended so the valid states a cell can take are not just discrete (for example, the states consist of integers between 0 and 3), but continuous, for example, the real number range [0,1]. The cells however remain discretely separated from each other. One example is called computational verb cellular network (CVCN), of which the states of cells are in the region of [0,1].
Such automata can be used to model certain physical reactions more closely, such as diffusion. One such diffusion model could conceivably consist of a transition function based on the average values of the neighbourhood of the cell. Many implementations of Finite Element Analysis can be thought of as continuous automata, though this degree of abstraction away from the physics of the problem is probably inappropriate.
Continuous spatial automata resemble continuous automata in having continuous values, but they also have a continuous set of locations rather than restricting the values to a discrete grid of cells.
See also
Continuous spatial automaton
Cellular automaton
Reference notes
Cellular automata
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https://en.wikipedia.org/wiki/GNOME%20Storage
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GNOME Storage was a project to replace the traditional file system with a new document store. Storage was part of a larger design for a new desktop environment that was still under development. The current implementation includes natural language access and network transparency.
Storage is no longer being developed; its CVS tree has not been changed for several years. Since the introduction of Storage, desktop search came to prominence, and now GNOME desktop search projects (Beagle, also defunct, as well as Tracker, formerly MetaTracker) have largely supplanted the need for Storage.
See also
WinFS, a Microsoft project with similar goals
External links
GNOME Storage Homepage
GNOME
Storage software
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https://en.wikipedia.org/wiki/Hemiboreal
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Hemiboreal means halfway between the temperate and subarctic (or boreal) zones. The term is most frequently used in the context of climates and ecosystems.
Botany
A hemiboreal forest has some characteristics of a boreal forest to the north, and also shares features with temperate-zone forests to the south. Coniferous trees predominate in the hemiboreal zone, but a significant number of deciduous species, such as aspens, oaks, maples, ash trees, birches, beeches, hazels, and hornbeams, also take root here.
Climate
The term sometimes denotes the form of climate characteristic of the zone of hemiboreal forests—specifically, the climates designated Dfb, Dwb and Dsb in the Köppen climate classification scheme. On occasion, it is applied to all areas that have long, cold winters and warm (but not hot) summers—which also including areas that are semiarid(BS) and arid(BW) based on average annual precipitation. It can also be applied to some areas with a subpolar oceanic climate (Cfc), particularly those with continental climate characteristics.
Examples
Examples of locations with hemiboreal climates or ecosystems include:
Much of southern Canada (all of southeastern Canada except for parts of southern Ontario as well as the central Prairie Provinces outside the grasslands)
Within the United States: most parts of Michigan, Wisconsin, and Minnesota, along with eastern North Dakota and the Adirondacks of New York State and Northern New England. Also, many mountain areas in the western United States.
The Southern Siberian rainforest in Russia includes hemiboreal forests.
Parts of northeast China bordering Russia
Northern areas of Japan including Hokkaido
Parts of southern Norway and Southern Sweden except the most southern municipalities.
Latvia, Lithuania, Belarus and Estonia.
Coastal zone and archipelago of Turku in Finland and region of Åland.
The Australian Alps in eastern Victoria and southeastern New South Wales, which makes up a small portion in the southeastern
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https://en.wikipedia.org/wiki/Compaq%20Portable
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The Compaq Portable is an early portable computer which was one of the first IBM PC compatible systems. It was Compaq Computer Corporation's first product, to be followed by others in the Compaq Portable series and later Compaq Deskpro series. It was not simply an 8088-CPU computer that ran a Microsoft DOS as a PC "work-alike", but contained a reverse-engineered BIOS, and a version of MS-DOS that was so similar to IBM's PC DOS that it ran nearly all its application software. The computer was also an early variation on the idea of an "all-in-one".
It became available two years after the similar, but CP/M-based, Osborne 1 and Kaypro II. Columbia Data Products' MPC 1600 "Multi Personal Computer" had come out in June 1982. Other "work-alikes" included the MS-DOS and 8088-based, but not entirely IBM PC software compatible, Dynalogic Hyperion, Eagle Computer's Eagle 1600 series, including the Eagle Spirit portable, and the Corona personal computer. The latter two companies were threatened by IBM for BIOS copyright infringement, and settled out of court, agreeing to re-implement their BIOS. There was also the Seequa Chameleon, which had both 8088 and Z80 CPUs to alternately run MS-DOS or CP/M. Unlike Compaq, many of these companies had previously released computers based on Zilog's Z80 and Digital Research's CP/M operating system. Like Compaq, they recognized the replicability of the IBM PC's off-the-shelf parts, and saw that Microsoft retained the right to license MS-DOS to other companies. Only Compaq was able to fully capitalize on this, by aiming for complete IBM PC and PC DOS software compatibility, while reverse-engineering the BIOS to head off copyright legal claims.
Other contemporary systems include the portable Commodore SX-64, also known as the Executive 64, or VIP-64 in Europe, a briefcase/suitcase-size "luggable" version of the popular Commodore 64 home computer built with an 8-bit MOS 6510 (6502-based) CPU microprocessor, and the first full-color portabl
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https://en.wikipedia.org/wiki/Degree%20%28graph%20theory%29
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In graph theory, the degree (or valency) of a vertex of a graph is the number of edges that are incident to the vertex; in a multigraph, a loop contributes 2 to a vertex's degree, for the two ends of the edge. The degree of a vertex is denoted or . The maximum degree of a graph , denoted by , and the minimum degree of a graph, denoted by , are the maximum and minimum of its vertices' degrees. In the multigraph shown on the right, the maximum degree is 5 and the minimum degree is 0.
In a regular graph, every vertex has the same degree, and so we can speak of the degree of the graph. A complete graph (denoted , where is the number of vertices in the graph) is a special kind of regular graph where all vertices have the maximum possible degree, .
In a signed graph, the number of positive edges connected to the vertex is called positive deg and the number of connected negative edges is entitled negative deg.
Handshaking lemma
The degree sum formula states that, given a graph ,
.
The formula implies that in any undirected graph, the number of vertices with odd degree is even. This statement (as well as the degree sum formula) is known as the handshaking lemma. The latter name comes from a popular mathematical problem, which is to prove that in any group of people, the number of people who have shaken hands with an odd number of other people from the group is even.
Degree sequence
The degree sequence of an undirected graph is the non-increasing sequence of its vertex degrees; for the above graph it is (5, 3, 3, 2, 2, 1, 0). The degree sequence is a graph invariant, so isomorphic graphs have the same degree sequence. However, the degree sequence does not, in general, uniquely identify a graph; in some cases, non-isomorphic graphs have the same degree sequence.
The degree sequence problem is the problem of finding some or all graphs with the degree sequence being a given non-increasing sequence of positive integers. (Trailing zeroes may be ignored since they a
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https://en.wikipedia.org/wiki/RealNames
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RealNames was a company founded in 1997 by Keith Teare. Its goal was to create a multilingual keyword-based naming system for the Internet that would translate keywords typed into the address bar of Microsoft's Internet Explorer web browser to Uniform Resource Identifiers, based on the existing Domain Name System, that would access the page registered by the owner of the RealNames keyword.
In effect, to users of Internet Explorer, RealNames became a domain registry which was capable of registering names that worked without needing to belong to a top-level domain such as ".com" or ".net". RealNames and its backers expected this to be a lucrative source of income, and it raised more than $130 million of funding.
RealNames depended on its partnership with Microsoft, which offered the RealNames service on Internet Explorer. RealNames shut down operations in 2002 following a decision by Microsoft to redirect the 1 billion page views per calendar quarter that RealNames was resolving from the browser address bar into the MSN search engine.
In 2014, Tucows purchased RealNames.com. The domain now hosts a customized e-mail service, made possible by its acquisition of Mailbank and its long list of surname domain names.
See also
Alternative DNS root
References
Network addressing
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https://en.wikipedia.org/wiki/Index%20of%20molecular%20biology%20articles
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This is a list of topics in molecular biology. See also index of biochemistry articles.
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2-amino-4-deoxychorismate dehydrogenase - 2-dehydropantolactone reductase (B-specific) - 2-methylacyl-CoA dehydrogenase - 2-nitropropane dioxygenase - 2-oxobutyrate synthase - (2,3-dihydroxybenzoyl)adenylate synthase - 2,4-Dihydroxy-1,4-benzoxazin-3-one-glucoside dioxygenase - 2010107G12Rik - 27-hydroxycholesterol 7alpha-monooxygenase - 3' end - 3' flanking region - 3-hydroxy-2-methylpyridinecarboxylate dioxygenase - 3-Ketosteroid 9alpha-monooxygenase - 3-oxoacyl-(acyl-carrier-protein) reductase (NADH) - (3,5-dihydroxyphenyl)acetyl-CoA 1,2-dioxygenase - 3(or 17)a-hydroxysteroid dehydrogenase - 3110001I22Rik - 3alpha-hydroxyglycyrrhetinate dehydrogenase - 4932414N04Rik - 3alpha-hydroxysteroid dehydrogenase (A-specific) - 3alpha,7alpha,12alpha-trihydroxy-5beta-cholestanoyl-CoA 24-hydroxylase - 3alpha,7alpha,12alpha-trihydroxycholestan-26-al 26-oxidoreductase - 4-Cresol dehydrogenase (hydroxylating) - 4-Hydroxycyclohexanecarboxylate dehydrogenase - 4-hydroxyphenylacetaldehyde oxime monooxygenase - 4-hydroxyphenylpyruvate oxidase - 4-Nitrophenol 4-monooxygenase - 4933425L06Rik - 5' end - 5' flanking region - 5-pyridoxate dioxygenase - 6-endo-hydroxycineole dehydrogenase - 7-deoxyloganin 7-hydroxylase - 7beta-hydroxysteroid dehydrogenase (NADP+) - 8-oxocoformycin reductase - 12beta-hydroxysteroid dehydrogenase - 25-hydroxycholesterol 7α-hydroxylase -
A
abietadiene hydroxylase - acrylamide gels - Act 1 adaptor protein - adenine - adenosine deaminase deficiency - adenovirus - adenylyl-(glutamate—ammonia ligase) hydrolase - agarose gel electrophoresis - agarose gel - akaryocyte - Alagille syndrome - alkaline lysis - allele - amino acids - amino terminus - amp resistance - amplification - amplicon - anchor sequence - animal model - anneal - anthranilate adenylyltransferase - anti-sense strand - antibiotic resistance - antibody - antisense - antisense strand - AP-1 site - apo-beta
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https://en.wikipedia.org/wiki/Additive%20polynomial
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In mathematics, the additive polynomials are an important topic in classical algebraic number theory.
Definition
Let k be a field of prime characteristic p. A polynomial P(x) with coefficients in k is called an additive polynomial, or a Frobenius polynomial, if
as polynomials in a and b. It is equivalent to assume that this equality holds for all a and b in some infinite field containing k, such as its algebraic closure.
Occasionally absolutely additive is used for the condition above, and additive is used for the weaker condition that P(a + b) = P(a) + P(b) for all a and b in the field. For infinite fields the conditions are equivalent, but for finite fields they are not, and the weaker condition is the "wrong" as it does not behave well. For example, over a field of order q any multiple P of xq − x will satisfy P(a + b) = P(a) + P(b) for all a and b in the field, but will usually not be (absolutely) additive.
Examples
The polynomial xp is additive. Indeed, for any a and b in the algebraic closure of k one has by the binomial theorem
Since p is prime, for all n = 1, ..., p−1 the binomial coefficient is divisible by p, which implies that
as polynomials in a and b.
Similarly all the polynomials of the form
are additive, where n is a non-negative integer.
The definition makes sense even if k is a field of characteristic zero, but in this case the only additive polynomials are those of the form ax for some a in k.
The ring of additive polynomials
It is quite easy to prove that any linear combination of polynomials with coefficients in k is also an additive polynomial. An interesting question is whether there are other additive polynomials except these linear combinations. The answer is that these are the only ones.
One can check that if P(x) and M(x) are additive polynomials, then so are P(x) + M(x) and P(M(x)). These imply that the additive polynomials form a ring under polynomial addition and composition. This ring is denoted
This ring
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https://en.wikipedia.org/wiki/Embedded%20HTTP%20server
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An embedded HTTP server is an HTTP server used in an embedded system.
The HTTP server is usually implemented as a software component of an application (embedded) system that controls and/or monitors a machine with mechanical and/or electrical parts.
The HTTP server implements the HTTP protocol in order to allow communications with one or more local or remote users using a browser. The aim is to let users to interact with information provided by the embedded system (user interface, data monitoring, data logging, data configuration, etc.) via network, without using traditional peripherals required for local user interfaces (display, keyboard, etc.).
In some cases the functionalities provided via HTTP server allow also program-to-program communications, e.g. to retrieve data logged about the monitored machine, etc.
Usages
Examples of usage within an embedded application might be (e.g.):
to provide a thin client interface for a traditional application;
to provide indexing, reporting, and debugging tools during the development stage;
to implement a protocol for the distribution and acquisition of information to be displayed in the regular interface — possibly a web service, and possibly using XML as the data format;
to develop a web application.
Advantages
There are a few advantages to using HTTP to perform the above:
HTTP is a well studied cross-platform protocol and there are mature implementations freely available;
HTTP is seldom blocked by firewalls and intranet routers;
HTTP clients (e.g. web browsers) are readily available with all modern computers;
there is a growing tendency of using embedded HTTP servers in applications that parallels the rising trends of home-networking and ubiquitous computing.
Typical requirements
Natural limitations of the platforms where an embedded HTTP server runs contribute to the list of the non-functional requirements of the embedded, or more precise, embeddable HTTP server. Some of these requirements are the followin
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https://en.wikipedia.org/wiki/Workspace
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Workspace is a term used in various branches of engineering and economic development.
Business development
Workspace refers to small premises provided, often by local authorities or economic development agencies, to help new businesses to establish themselves. These typically provide not only physical space and utilities but also administrative services and links to support and finance organizations, as well as peer support among the tenants. A continuum of sophistication ranges through categories such as 'managed workspaces', 'business incubators' and 'business and employment co-operatives'. In cities, they are often set up in buildings that are disused but which the local authority wishes to retain as a landmark. At the larger end of the spectrum are business parks, virtual offices, technology parks and science parks.
Technology and software
In technology and software, "workspace" is a term used for several different purposes.
Software development
A workspace is (often) a file or directory that allows a user to gather various source code files and resources and work with them as a cohesive unit. Often these files and resources represent the complete state of an integrated development environment (IDE) at a given time, a snapshot. Workspaces are very helpful in cases of complex projects when maintenance can be challenging. Good examples of environments that allow users to create and use workspaces are Microsoft Visual Studio and Eclipse.
In configuration management, "workspace" takes on a different but related meaning; it is a part of the file system where the files of interest (for a given task like debugging, development, etc.) are located. It stores the user's view of the files stored in the configuration management's repository.
In either case, workspace acts as an environment where a programmer can work, isolated from the outside world, for the task duration.
Graphical interfaces
Additionally, workspaces refer to the grouping of windows in some window m
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https://en.wikipedia.org/wiki/Immunoassay
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An immunoassay (IA) is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes). The molecule detected by the immunoassay is often referred to as an "analyte" and is in many cases a protein, although it may be other kinds of molecules, of different sizes and types, as long as the proper antibodies that have the required properties for the assay are developed. Analytes in biological liquids such as serum or urine are frequently measured using immunoassays for medical and research purposes.
Immunoassays come in many different formats and variations. Immunoassays may be run in multiple steps with reagents being added and washed away or separated at different points in the assay. Multi-step assays are often called separation immunoassays or heterogeneous immunoassays. Some immunoassays can be carried out simply by mixing the reagents and samples and making a physical measurement. Such assays are called homogeneous immunoassays, or less frequently non-separation immunoassays.
The use of a calibrator is often employed in immunoassays. Calibrators are solutions that are known to contain the analyte in question, and the concentration of that analyte is generally known. Comparison of an assay's response to a real sample against the assay's response produced by the calibrators makes it possible to interpret the signal strength in terms of the presence or concentration of analyte in the sample.
Principle
Immunoassays rely on the ability of an antibody to recognize and bind a specific macromolecule in what might be a complex mixture of macromolecules. In immunology the particular macromolecule bound by an antibody is referred to as an antigen and the area on an antigen to which the antibody binds is called an epitope.
In some cases, an immunoassay may use an antigen to detect for the presence of antibodies, which recognize that antigen, in a solution
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https://en.wikipedia.org/wiki/SDXF
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SDXF (Structured Data eXchange Format) is a data serialization format defined by RFC 3072. It allows arbitrary structured data of different types to be assembled in one file for exchanging between arbitrary computers.
The ability to arbitrarily serialize data into a self-describing format is reminiscent of XML, but SDXF is not a text format (as XML) — SDXF is not compatible with text editors. The maximal length of a datum (composite as well as elementary) encoded using SDXF is 16777215 bytes (one less than 16 MB).
Technical structure format
SDXF data can express arbitrary levels of structural depth. Data elements are self-documenting, meaning that the metadata (numeric, character string or structure) are encoded into the data elements. The design of this format is simple and transparent: computer programs access SDXF data with the help of well-defined functions, exempting programmers from learning the precise data layout.
The word "exchange" in the name reflects another kind of transparency: the SDXF functions provide a computer architecture independent conversion of the data. Serializations can be exchanged among computers (via direct network, file transfer or CD) without further measures. The SDXF functions on the receiving side handle architectural adaptation.
Structured data is data with patterns predictable more complex than strings of text.
Example
A commercial example: two companies want to exchange digital invoices. The invoices have the following hierarchical nested structure:
INVOICE
│
├─ INVOICE_NO
├─ DATE
├─ ADDRESS_SENDER
│ ├─ NAME
│ ├─ NAME
│ ├─ STREET
│ ├─ ZIP
│ ├─ CITY
│ └─ COUNTRY
├─ ADDRESS_RECIPIENT
│ ├─ NAME
│ ├─ NAME
│ ├─ STREET
│ ├─ ZIP
│ ├─ CITY
│ └─ COUNTRY
├─ INVOICE_SUM
├─ SINGLE_ITEMS
│ ├─ SINGLE_ITEM
│ │ ├─ QUANTITY
│ │ ├─ ITEM_NUMBER
│ │ ├─ ITEM_TEXT
│ │ ├─ CHARGE
│ │ └─ SUM
│ └─ ...
├─ CONDITIONS
...
Structure
The ba
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https://en.wikipedia.org/wiki/Automatic%20identification%20and%20data%20capture
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Automatic identification and data capture (AIDC) refers to the methods of automatically identifying objects, collecting data about them, and entering them directly into computer systems, without human involvement. Technologies typically considered as part of AIDC include QR codes, bar codes, radio frequency identification (RFID), biometrics (like iris and facial recognition system), magnetic stripes, optical character recognition (OCR), smart cards, and voice recognition. AIDC is also commonly referred to as "Automatic Identification", "Auto-ID" and "Automatic Data Capture".
AIDC is the process or means of obtaining external data, particularly through the analysis of images, sounds, or videos. To capture data, a transducer is employed which converts the actual image or a sound into a digital file. The file is then stored and at a later time, it can be analyzed by a computer, or compared with other files in a database to verify identity or to provide authorization to enter a secured system. Capturing data can be done in various ways; the best method depends on application.
In biometric security systems, capture is the acquisition of or the process of acquiring and identifying characteristics such as finger image, palm image, facial image, iris print, or voiceprint which involves audio data, and the rest all involve video data.
Radio-frequency identification is relatively a new AIDC technology, which was first developed in the 1980s. The technology acts as a base in automated data collection, identification, and analysis systems worldwide. RFID has found its importance in a wide range of markets, including livestock identification and Automated Vehicle Identification (AVI) systems because of its capability to track moving objects. These automated wireless AIDC systems are effective in manufacturing environments where barcode labels could not survive.
Overview of automatic identification methods
Nearly all the automatic identification technologies consist of thre
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https://en.wikipedia.org/wiki/Wacom
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is a Japanese company headquartered in Kazo, Saitama, Japan, that specializes in manufacturing graphics tablets and related products.
Headquarters locations
The main headquarters are located in Kazo, Saitama, Japan. Its office in the USA is currently located in the Pearl District of Portland, Oregon. The European headquarters is located in the Media Harbour in Düsseldorf, Germany.
History
The company was founded in 1983 in Japan. The company released its first pen display in 1992 and was the first company to make pens without a cord.
Products
Wacom produces two categories of graphics tablets: those with a screen ('pen display') and those without ('tablet'). In addition, the company provides software for computers and software to interpret pen data. Some pens have an eraser on the rear end.
Cintiq
Wacom's professional pen displays are under the Cintiq line which allow for drawing directly on the screen like drawing on paper, which are more expensive than other Wacom products. The Cintiq Companion is a portable variant of the Cintiq displays.
Intuos
Intuos graphics tablets are smaller tablets, without displays. The Verge calls them a "great introduction to digital art."
Other products
In 2011, the company released a tablet-less pen, which allowed for drawing on any piece of paper, but was criticized for being inaccurate compared to a normal photo scan. The Wacom One, released at CES 2020, has a 13-inch, 1920x1080 display. The Verge labeled it as Wacom's "most affordable tablet to date," being priced at $400.
Wacoms other tablets, Bamboo, and Graphire, are both without screens.
Wacom partnered with Magic Leap to create collaborative mixed reality design tools, announced in 2018.
Technology
The pens use a movable tip to determine the pressure, and the tablets use patented electromagnetic resonance technology, a type of faint radio signal, called Electro Magnetic Resonance. This method does not require batteries in the pens.
Criticism
Wacom has been cri
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https://en.wikipedia.org/wiki/Electronic%20counter-countermeasure
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Electronic counter-countermeasures (ECCM) is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as electronic protective measures (EPM), chiefly in Europe. In practice, EPM often means resistance to jamming. A more detailed description defines it as the electronic warfare operations taken by a radar to offset the enemy's countermeasure.
History
Ever since electronics have been used in battle in an attempt to gain superiority over the enemy, effort has been spent on techniques to reduce the effectiveness of those electronics. More recently, sensors and weapons are being modified to deal with this threat. One of the most common types of ECM is radar jamming or spoofing. This originated with the Royal Air Force's use of what they codenamed Window during World War II, which Americans referred to as chaff. It was first used during the Hamburg raid on July 24-25, 1943. The night fighters outfitted with Window had prong antennae stuck out from their noses, allowing their radars a range of four miles in a 70 degree cone. Jamming also may have originated with the British during World War II, when they began jamming German radio communications. These efforts include the successful British disruption of German Luftwaffe navigational radio beams.
In perhaps the first example of ECCM, the Germans increased their radio transmitter power in an attempt to 'burn through' or override the British jamming, which by necessity of the jammer being airborne or further away produced weaker signals. This is still one of the primary methods of ECCM today. For example, modern airborne jammers are able to identify incoming radar signals from other aircraft and send them back with random delays and other modifications in an attempt to confuse the opponent's radar set, making the 'blip' jump
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https://en.wikipedia.org/wiki/E%20%28programming%20language%29
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E is an object-oriented programming language for secure distributed computing, created by Mark S. Miller, Dan Bornstein, Douglas Crockford, Chip Morningstar and others at Electric Communities in 1997. E is mainly descended from the concurrent language Joule and from Original-E, a set of extensions to Java for secure distributed programming. E combines message-based computation with Java-like syntax. A concurrency model based on event loops and promises ensures that deadlock can never occur.
Philosophy
The E language is designed for computer security and secure computing. This is performed mainly by strict adherence to the object-oriented computing model, which in its pure form, has properties that support secure computing. The E language and its standard library employ a capability-based design philosophy throughout in order to help programmers build secure software and to enable software components to co-operate even if they don't fully trust each other. In E, object references serve as capabilities, hence capabilities add no computational or conceptual overhead costs. The language syntax is designed to be easy for people to audit for security flaws. For example, lexical scoping limits the amount of code that must be examined for its effects on a given variable. As another example, the language uses the == operator for comparison and the := operator for assignment; to avoid the possibility of confusion, there is no = operator.
Computational model
In E, all values are objects and computation is performed by sending messages to objects. Each object belongs to a vat (analogous to a process). Each vat has a single thread of execution, a stack frame, and an event queue. Distributed programming is just a matter of sending messages to remote objects (objects in other vats). All communication with remote parties is encrypted by the E runtime. Arriving messages are placed into the vat's event queue; the vat's event loop processes the incoming messages one by one in order
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https://en.wikipedia.org/wiki/Trimorphism
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In biology, trimorphism is the existence in certain plants and animals of three distinct forms, especially in connection with the reproductive organs.
In trimorphic plants there are three forms, differing in the lengths of their pistils and stamens, in size and color of their pollen grains, and in some other respects; and, as in each of the three forms there are two sets of stamens, the three forms possess altogether six sets of stamens and three kinds of pistils. These organs are so proportioned in length to each other that half the stamens in two of the forms stand on a level with the stigma of the third form. To obtain full fertility with these plants, it is necessary that the stigma of the one should be fertilized by pollen taken from the stamens of corresponding height in another form. Hence six unions are legitimate, that is, fully fertile, and 12 are illegitimate, or more or less unfertile. Wallace has shown that the females of certain butterflies from the Malay Archipelago appear in three conspicuously distinct forms without intermediate links.
In crystallography, trimorphism refers to the occurrence of certain forms in minerals which have the same chemical composition, but are referable to three systems of crystallization.
See also
Sexual dimorphism
Notes
Text from Collier's New Encyclopedia (1921).
Plant physiology
Pollination
Sex
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https://en.wikipedia.org/wiki/Phragm%C3%A9n%E2%80%93Lindel%C3%B6f%20principle
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In complex analysis, the Phragmén–Lindelöf principle (or method), first formulated by Lars Edvard Phragmén (1863–1937) and Ernst Leonard Lindelöf (1870–1946) in 1908, is a technique which employs an auxiliary, parameterized function to prove the boundedness of a holomorphic function (i.e, ) on an unbounded domain when an additional (usually mild) condition constraining the growth of on is given. It is a generalization of the maximum modulus principle, which is only applicable to bounded domains.
Background
In the theory of complex functions, it is known that the modulus (absolute value) of a holomorphic (complex differentiable) function in the interior of a bounded region is bounded by its modulus on the boundary of the region. More precisely, if a non-constant function is holomorphic in a bounded region and continuous on its closure , then for all . This is known as the maximum modulus principle. (In fact, since is compact and is continuous, there actually exists some such that .) The maximum modulus principle is generally used to conclude that a holomorphic function is bounded in a region after showing that it is bounded on its boundary.
However, the maximum modulus principle cannot be applied to an unbounded region of the complex plane. As a concrete example, let us examine the behavior of the holomorphic function in the unbounded strip
.
Although , so that is bounded on boundary , grows rapidly without bound when along the positive real axis. The difficulty here stems from the extremely fast growth of along the positive real axis. If the growth rate of is guaranteed to not be "too fast," as specified by an appropriate growth condition, the Phragmén–Lindelöf principle can be applied to show that boundedness of on the region's boundary implies that is in fact bounded in the whole region, effectively extending the maximum modulus principle to unbounded regions.
Outline of the technique
Suppose we are given a holomorphic function and
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https://en.wikipedia.org/wiki/Lochia
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In the field of obstetrics, lochia is the vaginal discharge after giving birth, containing blood, mucus, and uterine tissue. Lochia discharge typically continues for four to eight weeks after childbirth, a time known as the postpartum period or puerperium. A 2016 review ties this "lochial period" to worldwide customs of postpartum confinement, a time for the new mother and baby to bond.
Lochia is sterile for the first two days, but not so by the third or fourth day, as the uterus begins to be colonized by vaginal commensals such as non-hemolytic streptococci and E. coli.
Stages
It progresses through three stages:
Lochia rubra (or cruenta) is the first discharge, composed of blood, shreds of fetal membranes, decidua, vernix caseosa, lanugo and membranes. It is red in color because of the large amount of blood it contains. It lasts 1 to 4 days after birth, before easing to light "spotting".
Lochia serosa is the term for lochia that has thinned and turned brownish or pink in color. It contains serous exudate, erythrocytes, leukocytes, cervical mucus and microorganisms. This stage continues until around the tenth day after delivery. Lochia serosa which persists to some weeks after birth can indicate late postpartum hemorrhaging, and should be reported to a physician.
Lochia alba (or purulenta) is the name for lochia once it has turned whitish or yellowish-white. It typically lasts from the second through the third to sixth weeks after delivery. It contains fewer red blood cells and is mainly made up of leukocytes, epithelial cells, cholesterol, fat, mucus and microorganisms. Continuation beyond a few weeks can indicate a genital lesion, which should be reported to a physician.
Complications
In general, lochia has an odor similar to that of normal menstrual fluid. Any offensive odor or change to a greenish color indicates contamination by organisms such as chlamydia or staph saprophyticus.
Lochia that is retained within the uterus is known as lochiostasis or lochio
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https://en.wikipedia.org/wiki/Zeckendorf%27s%20theorem
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In mathematics, Zeckendorf's theorem, named after Belgian amateur mathematician Edouard Zeckendorf, is a theorem about the representation of integers as sums of Fibonacci numbers.
Zeckendorf's theorem states that every positive integer can be represented uniquely as the sum of one or more distinct Fibonacci numbers in such a way that the sum does not include any two consecutive Fibonacci numbers. More precisely, if is any positive integer, there exist positive integers , with , such that
where is the th Fibonacci number. Such a sum is called the Zeckendorf representation of . The Fibonacci coding of can be derived from its Zeckendorf representation.
For example, the Zeckendorf representation of 64 is
.
There are other ways of representing 64 as the sum of Fibonacci numbers
but these are not Zeckendorf representations because 34 and 21 are consecutive Fibonacci numbers, as are 5 and 3.
For any given positive integer, its Zeckendorf representation can be found by using a greedy algorithm, choosing the largest possible Fibonacci number at each stage.
History
While the theorem is named after the eponymous author who published his paper in 1972, the same result had been published 20 years earlier by Gerrit Lekkerkerker. As such, the theorem is an example of Stigler's Law of Eponymy.
Proof
Zeckendorf's theorem has two parts:
Existence: every positive integer has a Zeckendorf representation.
Uniqueness: no positive integer has two different Zeckendorf representations.
The first part of Zeckendorf's theorem (existence) can be proven by induction. For it is clearly true (as these are Fibonacci numbers), for we have . If is a Fibonacci number then there is nothing to prove. Otherwise there exists such that . Now suppose each positive integer has a Zeckendorf representation (induction hypothesis) and consider . Since , has a Zeckendorf representation by the induction hypothesis. At the same time, (we apply the definition of Fibonacci number in
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https://en.wikipedia.org/wiki/Pentium%20F00F%20bug
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The Pentium F00F bug is a design flaw in the majority of Intel Pentium, Pentium MMX, and Pentium OverDrive processors (all in the P5 microarchitecture). Discovered in 1997, it can result in the processor ceasing to function until the computer is physically rebooted. The bug has been circumvented through operating system updates.
The name is shorthand for F0 0F C7 C8, the hexadecimal encoding of one offending instruction. More formally, the bug is called the invalid operand with locked CMPXCHG8B instruction bug.
Description
In the x86 architecture, the byte sequence F0 0F C7 C8 represents the instruction lock cmpxchg8b eax (locked compare and exchange of 8 bytes in register EAX). The bug also applies to opcodes ending in C9 through CF, which specify register operands other than EAX. The F0 0F C7 C8 instruction does not require any special privileges.
This instruction encoding is invalid. The cmpxchg8b instruction compares the value in the EDX and EAX registers with an 8-byte value in a memory location. In this case, however, a register is specified instead of a memory location, which is not allowed.
Under normal circumstances, this would simply result in an exception; however, when used with the lock prefix (normally used to prevent two processors from interfering with the same memory location), the CPU erroneously uses locked bus cycles to read the illegal instruction exception-handler descriptor. Locked reads must be paired with locked writes, and the CPU's bus interface enforces this by forbidding other memory accesses until the corresponding writes occur. As none are forthcoming, after performing these bus cycles all CPU activity stops, and the CPU must be reset to recover.
Due to the proliferation of Intel microprocessors, the existence of this open-privilege instruction was considered a serious issue at the time. Operating system vendors responded by implementing workarounds that detected the condition and prevented the crash. Information about the bug fir
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https://en.wikipedia.org/wiki/Multi-Vendor%20Integration%20Protocol
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The Multi-Vendor Integration Protocol (MVIP) is a hardware bus for computer telephony integration (Audiotex) equipment, a PCM data highway for interconnecting expansion boards inside a PC. It was invented and brought to market by Natural Microsystems Inc (now BPQ Communicationser).
Used to build call center equipment using regular PCs, MVIP provides a second communications bus within the computer that can multiplex up to 256 full-duplex voice channels from one voice card to another. Digital voice, fax and video is bussed over a ribbon cable connected at the top of each ISA or PCI card. MVIP products make a PC perform like a small-scale PBX. The protocol accommodated for a variety of expansion boards, including trunk interfaces (usually T1 or ISDN), voice processing boards equipment speech recognition or fax processing. Each board could optionally provide a switch that could interconnect voice channels on the bus, allowing for a flexible routing of calls within the MVIP bus.
The MVIP bus was promoted as an alternative to the then-dominant PEB bus by Dialogic Corporation which had much less capacity and was not an open standard.
References
External links
http://www.mvip.org/
http://www.mvip.org/Overview.htm
Computer buses
Computer telephony integration
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https://en.wikipedia.org/wiki/Whisker%20%28metallurgy%29
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Metal whiskering is a phenomenon that occurs in electrical devices when metals form long whisker-like projections over time. Tin whiskers were noticed and documented in the vacuum tube era of electronics early in the 20th century in equipment that used pure, or almost pure, tin solder in their production. It was noticed that small metal hairs or tendrils grew between metal solder pads, causing short circuits. Metal whiskers form in the presence of compressive stress. Germanium, zinc, cadmium, and even lead whiskers have been documented. Many techniques are used to mitigate the problem, including changes to the annealing process (heating and cooling), the addition of elements like copper and nickel, and the inclusion of conformal coatings. Traditionally, lead has been added to slow down whisker growth in tin-based solders.
Following the Restriction of Hazardous Substances Directive (RoHS), the European Union banned the use of lead in most consumer electronic products from 2006 due to health problems associated with lead and the "high-tech trash" problem, leading to a re-focusing on the issue of whisker formation in lead-free solders.
Mechanism
Metal whiskering is a crystalline metallurgical phenomenon involving the spontaneous growth of tiny, filiform hairs from a metallic surface. The effect is primarily seen on elemental metals but also occurs with alloys.
The mechanism behind metal whisker growth is not well understood, but seems to be encouraged by compressive mechanical stresses including:
energy gained due to electrostatic polarization of metal filaments in the electric field,
residual stresses caused by electroplating,
mechanically induced stresses,
stresses induced by diffusion of different metals,
thermally induced stresses, and
strain gradients in materials.
Metal whiskers differ from metallic dendrites in several respects: dendrites are fern-shaped and grow across the surface of the metal, while metal whiskers are hair-like and project normal to
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https://en.wikipedia.org/wiki/Vacuum%20grease
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Vacuum grease is a lubricant with low volatility and is used for applications in low pressure environments. Lubricants with higher volatility would evaporate, causing two problems:
They would not be present to provide lubrication.
They would make lowering the pressure below their vapor pressure difficult.
As well as a lubricant, vacuum grease is also used as a sealant for joints in vacuum systems. This is usually limited to soft vacuums, as ultra high vacuum or high temperatures may give problems with the grease outgassing. Grease is most commonly used with glass vacuum systems. All metal systems usually use knife-edge seals in soft metals instead. Where O ring seals are used, these should not be greased (in static seals at least) as it can cause the O rings to become permanently distorted when compressed.
In electronics manufacturing processes, vacuum grease is often used to prevent corrosion.
One of the early vacuum greases is the Ramsay grease.
Examples
Perfluoropolyether
References
Grease
Lubricants
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https://en.wikipedia.org/wiki/IEEE%20802.1Q
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IEEE 802.1Q, often referred to as Dot1q, is the networking standard that supports virtual local area networking (VLANs) on an IEEE 802.3 Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames. The standard also contains provisions for a quality-of-service prioritization scheme commonly known as IEEE 802.1p and defines the Generic Attribute Registration Protocol.
Portions of the network which are VLAN-aware (i.e., IEEE 802.1Q conformant) can include VLAN tags. When a frame enters the VLAN-aware portion of the network, a tag is added to represent the VLAN membership. Each frame must be distinguishable as being within exactly one VLAN. A frame in the VLAN-aware portion of the network that does not contain a VLAN tag is assumed to be flowing on the native VLAN.
The standard was developed by IEEE 802.1, a working group of the IEEE 802 standards committee, and continues to be actively revised with notable amendments including IEEE 802.1ad, IEEE 802.1ak and IEEE 802.1s. The 802.1Q-2014 revision incorporated the IEEE 802.1D-2004 standard.
Frame format
802.1Q adds a 32-bit field between the source MAC address and the EtherType fields of the original frame. Under 802.1Q, the maximum frame size is extended from 1,518 bytes to 1,522 bytes. The minimum frame size remains 64 bytes, but a bridge may extend the minimum size frame from 64 to 68 bytes on transmission. This allows a tag to be popped without needing additional padding. Two bytes are used for the tag protocol identifier (TPID), the other two bytes for tag control information (TCI). The TCI field is further divided into PCP, DEI, and VID.
Tag protocol identifier (TPID)
A 16-bit field set to a value of 0x8100 in order to identify the frame as an IEEE 802.1Q-tagged frame. This field is located at the same position as the EtherType field in untagged frames, and is thus used to distinguish the fram
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https://en.wikipedia.org/wiki/Linalool
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Linalool () refers to two enantiomers of a naturally occurring terpene alcohol found in many flowers and spice plants. Linalool has multiple commercial applications, the majority of which are based on its pleasant scent (floral, with a touch of spiciness). A colorless oil, linalool is classified as an acyclic monoterpenoid. In plants, it is a metabolite, a volatile oil component, an antimicrobial agent, and an aroma compound. Linalool has uses in manufacturing of soaps, fragrances, food additives as flavors, household products, and insecticides. Esters of linalool are referred to as linalyl, e.g. linalyl pyrophosphate, an isomer of geranyl pyrophosphate.
The word linalool is based on linaloe (a type of wood) and the suffix . In food manufacturing, it may be called coriandrol.
Occurrence
Both enantiomeric forms are found in nature: (S)-linalool is found, for example, as a major constituent of the essential oils of coriander (Coriandrum sativum L.), cymbopogon (Cymbopogon martini var. martinii), and sweet orange (Citrus sinensis) flowers. (R)-linalool is present in lavender (Lavandula officinalis), bay laurel (Laurus nobilis), and sweet basil (Ocimum basilicum), among others.
Each enantiomer evokes distinct neural responses in humans, so each is classified as possessing distinct scents. (S)-(+)-Linalool is perceived as sweet, floral, petitgrain-like (odor threshold 7.4 ppb) and the (R)-form as more woody and lavender-like (odor threshold 0.8 ppb).
Over 200 species of plants produce linalool, notably from the families Lamiaceae (mint and other herbs), Lauraceae (laurels, cinnamon, rosewood), and Rutaceae (citrus fruits), but also birch trees and other plants, from tropical to boreal climate zones.
Lavandula
Cinnamomum tamala
Cannabis sativa
Basil
Solidago
Artemisia vulgaris (mugwort)
Humulus lupulus
It was first synthesized in the laboratory of Leopold Ružička in 1919.
Biosynthesis
In higher plants linalool is formed by rearrangement of geranyl pyropho
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https://en.wikipedia.org/wiki/Carl%20Gustav%20Hempel
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Carl Gustav "Peter" Hempel (January 8, 1905 – November 9, 1997) was a German writer, philosopher, logician, and epistemologist. He was a major figure in logical empiricism, a 20th-century movement in the philosophy of science. He is especially well known for his articulation of the deductive-nomological model of scientific explanation, which was considered the "standard model" of scientific explanation during the 1950s and 1960s. He is also known for the raven paradox (also known as "Hempel's paradox").
Education
Hempel studied mathematics, physics and philosophy at the University of Göttingen and subsequently at the University of Berlin and the Heidelberg University. In Göttingen, he encountered David Hilbert and was impressed by his program attempting to base all mathematics on solid logical foundations derived from a limited number of axioms.
After moving to Berlin, Hempel participated in a congress on scientific philosophy in 1929 where he met Rudolf Carnap and became involved in the Berlin Circle of philosophers associated with the Vienna Circle. In 1934, he received his doctoral degree from the University of Berlin with a dissertation on probability theory, titled Beiträge zur logischen Analyse des Wahrscheinlichkeitsbegriffs (Contributions to the Logical Analysis of the Concept of Probability). Hans Reichenbach was Hempel's main doctoral supervisor, but after Reichenbach lost his philosophy chair in Berlin in 1933, Wolfgang Köhler and Nicolai Hartmann became the official supervisors.
Career
Within a year of completing his doctorate, the increasingly repressive and anti-semitic Nazi regime in Germany had prompted Hempel to emigrate to Belgium as his wife was of Jewish ancestry. In this he was aided by the scientist Paul Oppenheim, with whom he co-authored the book Der Typusbegriff im Lichte der neuen Logik on typology and logic in 1936. In 1937, Hempel emigrated to the United States, where he accepted a position as Carnap's assistant at the University of
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https://en.wikipedia.org/wiki/Science%20Horizons%20Survival
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Science Horizons Survival is a ZX Spectrum video game developed by Five Ways Software. It was published by Sinclair Research in association with Macmillan Education in 1984. It is an educational game in which the player takes on the role of one of a series of animals, and had to find food to survive while avoiding predators.
Gameplay
The aim was to teach users about food chains; as an insect life is short, with the constant danger of being eaten by a bird - but as an eagle the player is at the top of the food chain with mankind or starvation as the only dangers.
The simulation allows the player to be one of six animals: a hawk, a robin, a lion, a mouse, a fly or a butterfly. The world appears in scrolling grid form, with ice caps to the north and south. The player moves one square at a time, with visibility depending on the chosen animal, avoiding predators and find food and water. The game ends when the animal dies, either through starvation, dehydration, being killed by a predator, or old age.
Development
Survival was developed as part of a series of educational software aimed at children aged between 5 and 12. This "Science Horizons" series was instigated by Sir Clive Sinclair and ex-Prime Minister Harold Macmillan.
Reception
CRASH magazine described Survival as an interesting and enjoyable program which can be used to reinforce learning, or on a self-discovery basis. One criticism was difficulty in remembering the control keys.
References
External links
Survival at World of Spectrum
1984 video games
Survival video games
Biological simulation video games
Science educational video games
Children's educational video games
Video games developed in the United Kingdom
ZX Spectrum games
ZX Spectrum-only games
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https://en.wikipedia.org/wiki/Digest%20access%20authentication
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Digest access authentication is one of the agreed-upon methods a web server can use to negotiate credentials, such as username or password, with a user's web browser. This can be used to confirm the identity of a user before sending sensitive information, such as online banking transaction history. It applies a hash function to the username and password before sending them over the network. In contrast, basic access authentication uses the easily reversible Base64 encoding instead of hashing, making it non-secure unless used in conjunction with TLS.
Technically, digest authentication is an application of MD5 cryptographic hashing with usage of nonce values to prevent replay attacks. It uses the HTTP protocol.
Overview
Digest access authentication was originally specified by (An Extension to HTTP: Digest Access Authentication). RFC 2069 specifies roughly a traditional digest authentication scheme with security maintained by a server-generated nonce value. The authentication response is formed as follows (where HA1 and HA2 are names of string variables):
HA1 = MD5(username:realm:password)
HA2 = MD5(method:digestURI)
response = MD5(HA1:nonce:HA2)
An MD5 hash is a 16-byte value. The HA1 and HA2 values used in the computation of the response are the hexadecimal representation (in lowercase) of the MD5 hashes respectively.
RFC 2069 was later replaced by (HTTP Authentication: Basic and Digest Access Authentication). RFC 2617 introduced a number of optional security enhancements to digest authentication; "quality of protection" (qop), nonce counter incremented by client, and a client-generated random nonce. These enhancements are designed to protect against, for example, chosen-plaintext attack cryptanalysis.
If the algorithm directive's value is "MD5" or unspecified, then HA1 is
HA1 = MD5(username:realm:password)
If the algorithm directive's value is "MD5-sess", then HA1 is
HA1 = MD5(MD5(username:realm:password):nonce:cnonce)
If the qop directive's value is "
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https://en.wikipedia.org/wiki/IEEE%20802.22
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IEEE 802.22, is a standard for wireless regional area network (WRAN) using white spaces in the television (TV) frequency spectrum.
The development of the IEEE 802.22 WRAN standard is aimed at using cognitive radio (CR) techniques to allow sharing of geographically unused spectrum allocated to the television broadcast service, on a non-interfering basis, to bring broadband access to hard-to-reach, low population density areas, typical of rural environments, and is therefore timely and has the potential for a wide applicability worldwide. It is the first worldwide effort to define a standardized air interface based on CR techniques for the opportunistic use of TV bands on a non-interfering basis.
IEEE 802.22 WRANs are designed to operate in the TV broadcast bands while assuring that no harmful interference is caused to the incumbent operation: digital TV and analog TV broadcasting, and low power licensed devices such as wireless microphones.
The standard was expected to be finalized in Q1 2010, but was finally published in July 2011.
IEEE P802.22.1 is a related standard being developed to enhance harmful interference protection for low power licensed devices operating in TV Broadcast Bands..
IEEE P802.22.2 is a recommended practice for the installation and deployment of IEEE 802.22 Systems.
IEEE 802.22 WG is a working group of IEEE 802 LAN/MAN standards committee which was chartered to write the 802.22 standard. The two 802.22 task groups (TG1 and TG2) are writing 802.22.1 and 802.22.2 respectively.
Technology
In response to a notice of proposed rulemaking (NPRM) issued by the U.S. Federal Communications Commission (FCC) in May 2004, the IEEE 802.22 working group on Wireless Regional Area Networks was formed in October 2004.
Its project, formally called as Standard for Wireless Regional Area Networks (WRAN) - Specific requirements - Part 22: Cognitive Wireless RAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Policies and procedures for oper
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https://en.wikipedia.org/wiki/List%20of%20coastal%20weather%20stations%20in%20the%20British%20Isles
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Reports from these coastal stations and automatic weather logging stations in the British Isles are included in the extended Shipping Forecasts on BBC Radio 4 at 0048 and 0520 local time each day.
The stations are listed in the order they are read in the forecast, the numbers in brackets refer to the map on the right. Weather reports included in the forecasts are issued at 2300 local time for the late broadcast and 0400 for the early one, although reports issued at other times may be included if for some reason, the most recent weather report did not arrive.
The report from each station is read in the following format: wind direction and speed, visibility in nautical miles, air pressure and pressure trend (steady, rising, or falling with rate of change).
Tiree Automatic (1)
Stornoway (2)
Lerwick (3)
Wick Automatic (0048 only)
Aberdeen (0048 only)
Leuchars (4)
Boulmer (0048 only)
Bridlington (5)
Sandettie Light Vessel Automatic (6)
Greenwich Light Vessel Automatic (7)
St. Catherine's Point Automatic (0048 only)
Jersey (8)
Channel Light Vessel Automatic (9)
Scilly Automatic (10)
Milford Haven (0048 only)
Aberporth (0048 only)
Valley (0048 only)
Liverpool Crosby (0048 only)
Valentia (11)
Ronaldsway (12)
Malin Head (13)
Machrihanish Automatic (0048 only)
See also
Coastline of the United Kingdom
Shipping Forecast
Inshore coastal areas of the United Kingdom
References
Meteorological data and networks
Marine meteorology
Weather
weather stations
weather stations
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https://en.wikipedia.org/wiki/Orthogonal%20transformation
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In linear algebra, an orthogonal transformation is a linear transformation T : V → V on a real inner product space V, that preserves the inner product. That is, for each pair of elements of V, we have
Since the lengths of vectors and the angles between them are defined through the inner product, orthogonal transformations preserve lengths of vectors and angles between them. In particular, orthogonal transformations map orthonormal bases to orthonormal bases.
Orthogonal transformations are injective: if then , hence , so the kernel of is trivial.
Orthogonal transformations in two- or three-dimensional Euclidean space are stiff rotations, reflections, or combinations of a rotation and a reflection (also known as improper rotations). Reflections are transformations that reverse the direction front to back, orthogonal to the mirror plane, like (real-world) mirrors do. The matrices corresponding to proper rotations (without reflection) have a determinant of +1. Transformations with reflection are represented by matrices with a determinant of −1. This allows the concept of rotation and reflection to be generalized to higher dimensions.
In finite-dimensional spaces, the matrix representation (with respect to an orthonormal basis) of an orthogonal transformation is an orthogonal matrix. Its rows are mutually orthogonal vectors with unit norm, so that the rows constitute an orthonormal basis of V. The columns of the matrix form another orthonormal basis of V.
If an orthogonal transformation is invertible (which is always the case when V is finite-dimensional) then its inverse is another orthogonal transformation. Its matrix representation is the transpose of the matrix representation of the original transformation.
Examples
Consider the inner-product space with the standard euclidean inner product and standard basis. Then, the matrix transformation
is orthogonal. To see this, consider
Then,
The previous example can be extended to construct all orthogonal tran
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https://en.wikipedia.org/wiki/Great%20Wall%20of%20Gorgan
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The Great Wall of Gorgan is a Sasanian-era defense system located near modern Gorgan in the Golestān Province of northeastern Iran, at the southeastern corner of the Caspian Sea. The western, Caspian Sea, end of the wall is near the remains of the fort at: ; the eastern end of the wall, near the town of Pishkamar, is near the remains of the fort at: . The title coordinate is for the location of the remains of a fort midway along the wall.
The wall is located at a geographic narrowing between the Caspian Sea and the mountains of northeastern Iran. It is one of several Caspian Gates at the eastern part of a region known in antiquity as Hyrcania, on the nomadic route from the northern steppes to the Iranian heartland. The wall is believed to have protected the Sassanian Empire to the south from the peoples to the north, probably the White Huns. In his book Empires and Walls, Chaichian (2014) questions the validity of this interpretation using historical evidence of potential political-military threats in the region as well as the economic geography of Gorgan Wall's environs. It is described as "amongst the most ambitious and sophisticated frontier walls" ever built in the world, and the most important of the Sasanian defense fortifications.
It is long and wide, and features over 30 fortresses spaced at intervals of between . It is surpassed only by the walls systems of the Great Wall of China and Cheolli Jangseong (in modern-day North Korea) as the longest single-segment building and the longest defensive wall in existence.
Name
Among archaeologists the wall is also known as "The Red Snake" (Turkmen: Qizil Alan) because of the colour of its bricks. In Persian, it was popularized by the name "Alexander Barrier" ( Sadd-i-Iskandar) or "Alexander's Wall", as Alexander the Great is thought by early Muslims to have passed through the Caspian Gates on his hasty march to Hyrcania and the east. It is also known as the "Anushirvân Barrier" ( Sadd-i Anushiravan) and "Firuz/
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https://en.wikipedia.org/wiki/Linear%20time-invariant%20system
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In system analysis, among other fields of study, a linear time-invariant (LTI) system is a system that produces an output signal from any input signal subject to the constraints of linearity and time-invariance; these terms are briefly defined below. These properties apply (exactly or approximately) to many important physical systems, in which case the response of the system to an arbitrary input can be found directly using convolution: where is called the system's impulse response and ∗ represents convolution (not to be confused with multiplication). What's more, there are systematic methods for solving any such system (determining ), whereas systems not meeting both properties are generally more difficult (or impossible) to solve analytically. A good example of an LTI system is any electrical circuit consisting of resistors, capacitors, inductors and linear amplifiers.
Linear time-invariant system theory is also used in image processing, where the systems have spatial dimensions instead of, or in addition to, a temporal dimension. These systems may be referred to as linear translation-invariant to give the terminology the most general reach. In the case of generic discrete-time (i.e., sampled) systems, linear shift-invariant is the corresponding term. LTI system theory is an area of applied mathematics which has direct applications in electrical circuit analysis and design, signal processing and filter design, control theory, mechanical engineering, image processing, the design of measuring instruments of many sorts, NMR spectroscopy, and many other technical areas where systems of ordinary differential equations present themselves.
Overview
The defining properties of any LTI system are linearity and time invariance.
Linearity means that the relationship between the input and the output , both being regarded as functions, is a linear mapping: If is a constant then the system output to is ; if is a further input with system output then the output of the
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https://en.wikipedia.org/wiki/Passenger%20name%20record
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A passenger name record (PNR) is a record in the database of a computer reservation system (CRS) that contains the itinerary for a passenger or a group of passengers travelling together. The concept of a PNR was first introduced by airlines that needed to exchange reservation information in case passengers required flights of multiple airlines to reach their destination ("interlining"). For this purpose, IATA and ATA have defined standards for interline messaging of PNR and other data through the "ATA/IATA Reservations Interline Message Procedures - Passenger" (AIRIMP). There is no general industry standard for the layout and content of a PNR. In practice, each CRS or hosting system has its own proprietary standards, although common industry needs, including the need to map PNR data easily to AIRIMP messages, has resulted in many general similarities in data content and format between all of the major systems.
When a passenger books an itinerary, the travel agent or travel website user will create a PNR in the computer reservation system it uses. This is typically one of the large global distribution systems, such as Amadeus, Sabre, or Travelport (Apollo, Galileo, and Worldspan) but if the booking is made directly with an airline the PNR can also be in the database of the airline's CRS. This PNR is called the Master PNR for the passenger and the associated itinerary. The PNR is identified in the particular database by a record locator.
When portions of the travel are not provided by the holder of the master PNR, then copies of the PNR information are sent to the CRSs of the airlines that will be providing transportation. These CRSs will open copies of the original PNR in their own database to manage the portion of the itinerary for which they are responsible. Many airlines have their CRS hosted by one of the GDSs, which allows sharing of the PNR.
The record locators of the copied PNRs are communicated back to the CRS that owns the Master PNR, so all records remai
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https://en.wikipedia.org/wiki/Character%20group
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In mathematics, a character group is the group of representations of a group by complex-valued functions. These functions can be thought of as one-dimensional matrix representations and so are special cases of the group characters that arise in the related context of character theory. Whenever a group is represented by matrices, the function defined by the trace of the matrices is called a character; however, these traces do not in general form a group. Some important properties of these one-dimensional characters apply to characters in general:
Characters are invariant on conjugacy classes.
The characters of irreducible representations are orthogonal.
The primary importance of the character group for finite abelian groups is in number theory, where it is used to construct Dirichlet characters. The character group of the cyclic group also appears in the theory of the discrete Fourier transform. For locally compact abelian groups, the character group (with an assumption of continuity) is central to Fourier analysis.
Preliminaries
Let be an abelian group. A function mapping the group to the non-zero complex numbers is called a character of if it is a group homomorphism from to —that is, if for all .
If is a character of a finite group , then each function value is a root of unity, since for each there exists such that , and hence .
Each character f is a constant on conjugacy classes of G, that is, f(hgh−1) = f(g). For this reason, a character is sometimes called a class function.
A finite abelian group of order n has exactly n distinct characters. These are denoted by f1, ..., fn. The function f1 is the trivial representation, which is given by for all . It is called the principal character of G; the others are called the non-principal characters.
Definition
If G is an abelian group, then the set of characters fk forms an abelian group under pointwise multiplication. That is, the product of characters and is defined by for all . This grou
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https://en.wikipedia.org/wiki/Coopetition
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Coopetition or co-opetition (sometimes spelled "coopertition" or "co-opertition") is a neologism coined to describe cooperative competition. Coopetition is a portmanteau of cooperation and competition. Basic principles of co-opetitive structures have been described in game theory, a scientific field that received more attention with the book Theory of Games and Economic Behavior in 1944 and the works of John Forbes Nash on non-cooperative games. Coopetition occurs both at inter-organizational or intra-organizational levels.
Overview
The concept and term coopetition and its variants have been re-coined several times in history.
The concept appeared as early as 1913, being used to describe the relationships among proximate independent dealers of the Sealshipt Oyster System, who were instructed to cooperate for the benefit of the system while competing with each other for customers in the same city.
Inter-organizational
The term and the ideas around co-opetition gained wide attention within the business community after the publication in 1996 of the book by Brandenberger and Nalebuff bearing the same title. Until today this remains the reference work for both researchers and practitioners alike.
Giovanni Battista Dagnino and Giovanna Padula's conceptualized in their conference paper (2002) that, at the inter-organisational level, coopetition occurs when companies interact with partial congruence of interests. They cooperate with each other to reach a higher value creation, if compared to the value created without interaction, and struggle to achieve a competitive advantage.
Often coopetition takes place when companies that are in the same market work together in the exploration of knowledge and research of new products, at the same time that they compete for the market-share of their products and in the exploitation of the knowledge created. In this case, the interactions occur simultaneously and in different levels in the value chain. This is the case in the arr
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https://en.wikipedia.org/wiki/Cheap%20talk
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In game theory, cheap talk is communication between players that does not directly affect the payoffs of the game. Providing and receiving information is free. This is in contrast to signaling in which sending certain messages may be costly for the sender depending on the state of the world.
This basic setting set by Vincent Crawford and Joel Sobel has given rise to a variety of variants.
To give a formal definition, cheap talk is communication that is:
costless to transmit and receive
non-binding (i.e. does not limit strategic choices by either party)
unverifiable (i.e. cannot be verified by a third party like a court)
Therefore, an agent engaging in cheap talk could lie with impunity, but may choose in equilibrium not to do so.
Applications
Game theory
Cheap talk can, in general, be added to any game and has the potential to enhance the set of possible equilibrium outcomes. For example, one can add a round of cheap talk in the beginning of the Battle of the Sexes. Each player announces whether they intend to go to the football game, or the opera. Because the Battle of the Sexes is a coordination game, this initial round of communication may enable the players to select among multiple equilibria, thereby achieving higher payoffs than in the uncoordinated case. The messages and strategies which yield this outcome are symmetric for each player. They are: 1) announce opera or football with even probability 2) if a person announces opera (or football), then upon hearing this message the other person will say opera (or football) as well (Farrell and Rabin, 1996). If they both announce different options, then no coordination is achieved. In the case of only one player messaging, this could also give that player a first-mover advantage.
It is not guaranteed, however, that cheap talk will have an effect on equilibrium payoffs. Another game, the Prisoner's Dilemma, is a game whose only equilibrium is in dominant strategies. Any pre-play cheap talk will be ignored a
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https://en.wikipedia.org/wiki/Moneo
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Moneo, sometimes branded as mon€o, is an electronic purse system available on French bank cards to allow small purchases to be made without cash and used from 1999 to 2015.
The system is aimed at small retailers such as bakeries and cafés and intended for purchases of less than €30.
The card is inserted into a handheld Moneo reader by the merchant who enters the transaction amount for the customer. The customer then confirms the purchase by pushing a button on the keypad; the exact amount is debited from the card within a few seconds.
As well as the multipurpose bank card version, anonymous cards (also smart cards) are available for the use of people without bank accounts, such as children and tourists.
Supported by all French banks, Moneo was tested in Brittany and Montpellier in 2002, and from 2004 Moneo has been added to most French bank cards.
Moneo is based on the German system Geldkarte.
Moneo was launched in Tours on 30 September 1999 by economy minister Dominique Strauss-Kahn.
See also
Internet currency
Octopus card
Quick Wertkarte
References
External links
The official Moneo site
Banking in France
Smart cards
Payment systems
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https://en.wikipedia.org/wiki/KOI-8
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KOI-8 (КОИ-8) is an 8-bit character set standardized in GOST 19768-74. It is an extension of KOI-7 which allows the use of the Latin alphabet along with the Russian alphabet, both the upper and lower case letters; however, the letter Ёё and the uppercase Ъ are missed, the latter to avoid conflicts with the delete character (both are added in most extensions, see KOI8-B). The first 127 code points are identical to ASCII with the exception of the dollar sign $ (code point 24hex) replaced by the universal currency sign ¤. The rows x8_ and x9_ (code points 128–159) might be filled with the additional control characters from EBCDIC (code points 32–63).
This standard has become the base for the later Internet standards such as KOI8-R, KOI8-U, KOI8-RU and all the other derivatives.
Unicode is preferred to KOI-8 and its variants or other Cyrillic encodings in modern applications, especially on the Internet, making UTF-8 the dominant encoding for web pages. (For further discussion of Unicode's complete coverage, of 436 Cyrillic letters/code points, including for Old Cyrillic, and how single-byte character encodings, such as Windows-1251 and KOI8 variants, cannot provide this, see Cyrillic script in Unicode.)
Character set
The following table shows the KOI-8 encoding. Each character is shown with its equivalent Unicode code point.
See also
KOI character encodings
Footnotes
References
Character sets
Computing in the Soviet Union
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https://en.wikipedia.org/wiki/Gold%20plating
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Gold plating is a method of depositing a thin layer of gold onto the surface of another metal, most often copper or silver (to make silver-gilt), by chemical or electrochemical plating. This article covers plating methods used in the modern electronics industry; for more traditional methods, often used for much larger objects, see gilding.
Types
There are several types of gold plating used in the electronics industry:
Soft, pure gold plating is used in the semiconductor industry. The gold layer is easily soldered and wire bonded. Its Knoop hardness ranges between 60 and 85. The plating baths have to be kept free of contamination.
Soft, pure gold is deposited from special electrolytes. Entire printed circuit boards can be plated. This technology can be used for depositing layers suitable for wire bonding.
Bright hard gold on contacts, with Knoop hardness between 120–300 and purity of 99.7–99.9% gold. Often contains a small amount of nickel and/or cobalt; these elements interfere with die bonding, therefore the plating baths cannot be used for semiconductors.
Bright hard gold on printed circuit board tabs is deposited using lower concentration of gold in the baths. Usually contains nickel and/or cobalt as well. Edge connectors are often made by controlled-depth immersion of only the edge of the boards.
Gold plating chemistry
There are five recognized classes of gold plating chemistry:
Alkaline gold cyanide, for gold and gold alloy plating
Neutral gold cyanide, for high-purity plating
Acid gold plating for bright hard gold and gold alloy plating
Non-cyanide, generally sulphite or chloride-based for gold and gold alloy plating
Miscellaneous
Jewelry
Gold plating of silver is used in the manufacture of jewelry. The thickness of gold plating on jewellery is noted in microns (or micro-meters). The microns of thickness determines how long the gold plating lasts with usage. The jewellery industry denotes different qualities of gold plating in the following ter
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https://en.wikipedia.org/wiki/IWork
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iWork is an office suite of applications created by Apple for its macOS, iPadOS, and iOS operating systems, and also available cross-platform through the iCloud website.
iWork includes the presentation application Keynote, the word-processing and desktop-publishing application Pages, and the spreadsheet application Numbers. Apple's design goals in creating iWork have been to allow Mac users to easily create attractive documents and spreadsheets, making use of macOS's extensive font library, integrated spelling checker, sophisticated graphics APIs and its AppleScript automation framework.
The equivalent Microsoft Office applications to Pages, Numbers, and Keynote are Word, Excel, and PowerPoint, respectively. Although Microsoft Office applications cannot open iWork documents, iWork applications can open Office documents for editing, and export documents from iWork’s native formats (.pages, .numbers, .key) to Microsoft Office formats (.docx, .xlsx, .pptx, etc.) as well as to PDF files.
The oldest application in iWork is Keynote, first released as a standalone application in 2003 for use by Steve Jobs in his presentations. Steve Jobs announced Keynote saying "It's for when your presentation really matters".
Pages was released with the first iWork bundle in 2005; Numbers was added in 2007 with the release of iWork '08. The next release, iWork '09, also included beta access to iWork.com, an online service that allowed users to upload and share documents on the web, now integrated into Apple's iCloud service. A version of iWork for iOS was released in 2010 with the first iPad, and the apps have been regularly updated since, including the addition of iPhone support. In 2013, Apple launched iWork web apps in iCloud; even years later, however, their functionality is somewhat limited compared to equivalents on the desktop.
iWork was initially sold as a suite for $79, then later at $19.99 per app on OS X and $9.99 per app on iOS. Apple announced in October 2013 that all
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https://en.wikipedia.org/wiki/Rubik%27s%20Clock
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Rubik's Clock is a mechanical puzzle invented and patented by Christopher C. Wiggs and Christopher J. Taylor. The Hungarian sculptor and professor of architecture Ernő Rubik bought the patent from them to market the product under his name. It was first marketed in 1988.
Rubik's Clock is a two-sided puzzle, each side presenting nine clocks to the puzzler. There are four wheels, one at each corner of the puzzle, each allowing the corresponding corner clock to be rotated directly. (The corner clocks, unlike the other clocks, rotate on both sides of the puzzle simultaneously and can never be operated independently. Thus the puzzle contains only 14 independent clocks.)
There are also four buttons which span both sides of the puzzle; each button arranged such that if it is "in" on one side it is "out" on the other. The state of each button (in or out) determines whether the adjacent corner clock is mechanically connected to the three other adjacent clocks on the front side or on the back side: thus the configuration of the buttons determines which sets of clocks can be turned simultaneously by rotating a suitable wheel.
The aim of the puzzle is to set all nine clocks to 12 o'clock (straight up) on both sides of the puzzle simultaneously. The method to do so is to start by constructing a cross on both sides (at 12 o’clock) and then solving the corner clocks.
The Rubik’s clock is listed as one of the 17 WCA events, with records for fastest time to solve one puzzle, and the fastest average time to solve 5 puzzles (discarding the slowest and fastest times).
Combinations
Since there are 14 independent clocks, with 12 settings each, there are a total of =1,283,918,464,548,864 possible combinations for the clock faces. This does not count for the number of pin positions.
Notation
The puzzle is oriented with 12 o'clock on top, and either side in front. The following moves can be made:
Pin movements:
UR (top-right): Move the top-right pin up.
DR (bottom-right): Move
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https://en.wikipedia.org/wiki/Realized%20niche%20width
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Realized niche width is a phrase relating to ecology, is defined by the actual space that an organism inhabits and the resources it can access as a result of limiting pressures from other species (e.g. superior competitors). An organism's ecological niche is determined by the biotic and abiotic factors that make up that specific ecosystem that allow that specific organism to survive there. The width of an organism's niche is set by the range of conditions a species is able to survive in that specific environment.
Definition
The fundamental niche width of an organism refers to the theoretical range of conditions that an organism could survive and reproduce in without considering interspecific interactions. The fundamental niche exclusively considers limiting biotic and abiotic factors such as appropriate food sources and a suitable climate. The fundamental niche width often differs from the realized niche width (the areas where actually inhabited by a given species). This differentiation is due to interspecific competition with other species within their ecosystem while still considering the biotic and abiotic limiting factors. A species' realized niche is usually much narrower than its fundamental niche width as it is forced to adjust its niche around the superior competing species.
The physical area where a species lives, is its habitat. The set of environmental features essential to that species' survival, is its "niche." (Ecology. Begon, Harper, Townsend)
Importance
The difference between the realized and the fundamental niche is important in understanding how interactions with a variety of different species in one environment affects the fitness of another species. This is not only important in understanding how a species functions in an ecosystem, but it is also important in determining the potential and realized success of invasive species. Invasive species could thrive or be killed off in an environment where they would theoretically be able to exist bas
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https://en.wikipedia.org/wiki/Table%20of%20Lie%20groups
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This article gives a table of some common Lie groups and their associated Lie algebras.
The following are noted: the topological properties of the group (dimension; connectedness; compactness; the nature of the fundamental group; and whether or not they are simply connected) as well as on their algebraic properties (abelian; simple; semisimple).
For more examples of Lie groups and other related topics see the list of simple Lie groups; the Bianchi classification of groups of up to three dimensions; see classification of low-dimensional real Lie algebras for up to four dimensions; and the list of Lie group topics.
Real Lie groups and their algebras
Column legend
Cpt: Is this group G compact? (Yes or No)
: Gives the group of components of G. The order of the component group gives the number of connected components. The group is connected if and only if the component group is trivial (denoted by 0).
: Gives the fundamental group of G whenever G is connected. The group is simply connected if and only if the fundamental group is trivial (denoted by 0).
UC: If G is not simply connected, gives the universal cover of G.
Real Lie algebras
Complex Lie groups and their algebras
Note that a "complex Lie group" is defined as a complex analytic manifold that is also a group whose multiplication and inversion are each given by a holomorphic map. The dimensions in the table below are dimensions over C. Note that every complex Lie group/algebra can also be viewed as a real Lie group/algebra of twice the dimension.
Complex Lie algebras
The dimensions given are dimensions over C. Note that every complex Lie algebra can also be viewed as a real Lie algebra of twice the dimension.
The Lie algebra of affine transformations of dimension two, in fact, exist for any field. An instance has already been listed in the first table for real Lie algebras.
See also
Classification of low-dimensional real Lie algebras
Simple Lie group#Full classification
References
Lie gro
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https://en.wikipedia.org/wiki/StarText
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StarText was an online ASCII-based computer service run by the Fort Worth Star-Telegram and the Tandy Corporation and marketed in the Dallas-Fort Worth Metroplex newspaper circulation area from May 3, 1982 until March 3, 1997. Its name was derived from Star (representing the newspaper which would provide the content) and Text (representing the computer company which would provide the technology).
StarText was an "information on demand" online computer service created by Joe Donth, offered for the first time in 1982 by the Fort Worth Star-Telegram to subscribers in the Dallas-Fort Worth Metroplex. On May 3, 1982, StarText officially started providing its news and all-text content online, updated from 5am to midnight. There were no graphics, pictures or colors. Subscribers were called StarTexans. The content within StarText was written by subscribers of the service as well as employees of the newspaper.
Initially, the service charged $5.00 a month to subscribers who received updated news each day from 5am until midnight daily. At first subscribers had to call StarText using a 300 baud modem and enter four requests out of a choice of 50. StarText then delivered the information without further interactivity. To receive more information the subscriber had to repeat the same process. The first StarText system was provided by a Tandy Model II.
The subsequent multi-user version of StarText, developed by Serge Stein, was written in DIBOL and ran on Digital Equipment VAX 11/750s connected to banks of 1200 & 2400 baud modems. This version provided a menu of content including the Star-Telegram's news and classified advertising, and provided messaging between subscribers (early email), Grolier's encyclopedia, American Airlines Sabre flight schedules and home banking to a group of over four thousand dedicated computer users. Users could define their screen size to the system which would then deliver only as much text as would fit on the screen giving the user the opportunity t
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https://en.wikipedia.org/wiki/Hybridization%20probe
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In molecular biology, a hybridization probe (HP) is a fragment of DNA or RNA of usually 15–10000 nucleotide long which can be radioactively or fluorescently labeled. HP can be used to detect the presence of nucleotide sequences in analyzed RNA or DNA that are complementary to the sequence in the probe. The labeled probe is first denatured (by heating or under alkaline conditions such as exposure to sodium hydroxide) into single stranded DNA (ssDNA) and then hybridized to the target ssDNA (Southern blotting) or RNA (northern blotting) immobilized on a membrane or in situ.
To detect hybridization of the probe to its target sequence, the probe is tagged (or "labeled") with a molecular marker of either radioactive or (more recently) fluorescent molecules. Commonly used markers are 32P (a radioactive isotope of phosphorus incorporated into the phosphodiester bond in the probe DNA), digoxigenin, a non-radioactive, antibody-based marker, biotin or fluorescein. DNA sequences or RNA transcripts that have moderate to high sequence similarity to the probe are then detected by visualizing the hybridized probe via autoradiography or other imaging techniques. Normally, either X-ray pictures are taken of the filter, or the filter is placed under UV light. Detection of sequences with moderate or high similarity depends on how stringent the hybridization conditions were applied—high stringency, such as high hybridization temperature and low salt in hybridization buffers, permits only hybridization between nucleic acid sequences that are highly similar, whereas low stringency, such as lower temperature and high salt, allows hybridization when the sequences are less similar.
Hybridization probes used in DNA microarrays refer to DNA covalently attached to an inert surface, such as coated glass slides or gene chips, to which a mobile cDNA target is hybridized. Depending on the method, the probe may be synthesized using the phosphoramidite method, or it can be generated and labeled
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https://en.wikipedia.org/wiki/WiBro
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WiBro (wireless broadband) is a wireless broadband Internet technology developed by the South Korean telecoms industry. WiBro is the South Korean service name for IEEE 802.16e (mobile WiMAX) international standard. By the end of 2012, the Korean Communications Commission intends to increase WiBro broadband connection speeds to 10Mbit/s, around ten times the 2009 speed, which will complement their 1Gbit/s fibre-optic network. The WiBro networks were shut down at the end of 2018.
WiBro adopts TDD for duplexing, OFDMA for multiple access and 8.75/10.00 MHz as a channel bandwidth. WiBro was devised to overcome the data rate limitation of mobile phones (for example CDMA 1x) and to add mobility to broadband Internet access (for example ADSL or Wireless LAN). In February 2002, the Korean government allocated 100 MHz of electromagnetic spectrum in the 2.3–2.4 GHz band, and in late 2004 WiBro Phase 1 was standardized by the TTA of Korea and in late 2005 ITU reflected WiBro as IEEE 802.16e (mobile WiMAX). Two South Korean telecom companies (KT, SKT) launched commercial service in June 2006, and the monthly fees were around US$30.
WiBro base stations offer an aggregate data throughput of 30 to 50 Mbit/s per carrier and cover a radius of 1–5 km allowing for the use of portable internet usage. In detail, it provides mobility for moving devices up to 120 km/h (74.5 mi/h) compared to Wireless LAN having mobility up to walking speed and mobile phone technologies having mobility up to 250 km/h. From testing during the APEC Summit in Busan in late 2005, the actual range and bandwidth were quite a bit lower than these numbers. The technology will also offer quality of service. The inclusion of QoS allows for WiBro to stream video content and other loss-sensitive data in a reliable manner. These all appear to be (and may be) the stronger advantages over the fixed WiMAX standard (802.16a). Some Telcos in many countries were trying to commercialize this Mobile WiMAX (or WiBro). For e
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https://en.wikipedia.org/wiki/Argos%20%28satellite%20system%29
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Argos is a global satellite-based system that collects, processes, and disseminates (spreads, distributes) environmental data from fixed and mobile platforms around the world. The worldwide tracking and environmental monitoring system is the results from Franco-American cooperation. In addition to satellite data collection, the main feature of the Argos system is its to ability to geographically locate the data source from any location on Earth using the Doppler effect; which refers to the apparent change in the wavelength due to relative motion between its source and observer. Argos is operated by CLS/Argos, based in Toulouse, France, and its United States subsidiary, CLS America.
History and utilization
Argos was established in 1978 and has provided data to environmental research and protection groups. It is a component of many global research programs including the Tropical Ocean-Global Atmosphere program (TOGA), Tagging of Pacific Pelagics (TOPP), World Ocean Circulation Experiment (WOCE) and, Argo. There are 22,000 active transmitters (8,000 of which are used in animal tracking) in over 100 countries.
Since the late 1980s, Argos transmitters have been deployed on a large number of marine mammals and sea turtles, and it is used for tracking long-distance movements of both coastal and oceanic species.
Argos was developed under a Memorandum of Understanding (MOU) between the Centre National d'Études Spatiales (CNES, France), the National Aeronautics and Space Administration (NASA, United States) and the National Oceanic and Atmospheric Administration (NOAA, United States).
The system utilizes both ground and satellite-based resources to accomplish its mission. These include:
instruments carried aboard the NOAA Polar Operational Environmental Satellites (POES), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) MetOp satellites, and Indian Space Research Organisation (ISRO) satellites,
receiving stations around the world
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https://en.wikipedia.org/wiki/Irradiation
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Irradiation is the process by which an object is exposed to radiation. An irradiator is a device used to expose an object to radiation, notably gamma radiation, for a variety of purposes. Irradiators may be used for sterilizing medical and pharmaceutical supplies, preserving foodstuffs, alteration of gemstone colors, studying radiation effects, eradicating insects through sterile male release programs, or calibrating thermoluminescent dosimeters (TLDs).
The exposure can originate from various sources, including natural sources. Most frequently the term refers to ionizing radiation, and to a level of radiation that will serve a specific purpose, rather than radiation exposure to normal levels of background radiation. The term irradiation usually excludes the exposure to non-ionizing radiation, such as infrared, visible light, microwaves from cellular phones or electromagnetic waves emitted by radio and television receivers and power supplies.
Applications
Sterilization
If administered at appropriate levels, all forms of ionizing radiation can sterilize objects, including medical instruments, disposables such as syringes, and sterilize food. Ionizing radiation (electron beams, X-rays and gamma rays) may be used to kill bacteria in food or other organic material, including blood. Food irradiation, while effective, is seldom used due to problems with public acceptance.
Medicine
Irradiation is used in diagnostic imaging, cancer therapy and blood transfusion.
In 2011 researchers found that irradiation was successful in the novel theranostic technique involving co-treatment with heptamethine dyes to elucidate tumor cells and attenuate their growth with minimal side effects.
Ion implantation
Ion irradiation is routinely used to implant impurities atoms into materials, especially
semiconductors, to modify their properties. This process, usually known
as ion implantation, is an important step in the manufacture of silicon integrated circuits.
Ion irradiation
Ion i
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https://en.wikipedia.org/wiki/Crash-only%20software
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Crash-only software refers to computer programs that handle failures by simply restarting, without attempting any sophisticated recovery. Correctly written components of crash-only software can microreboot to a known-good state without the help of a user. Since failure-handling and normal startup use the same methods, this can increase the chance that bugs in failure-handling code will be noticed, except when there are leftover artifacts, such as data corruption from a severe failure, that don't occur during normal startup.
Crash-only software also has benefits for end-users. All too often, applications do not save their data and settings while running, only at the end of their use. For example, word processors usually save settings when they are closed. A crash-only application is designed to save all changed user settings soon after they are changed, so that the persistent state matches that of the running machine. No matter how an application terminates (be it a clean close or the sudden failure of a laptop battery), the state will persist.
See also
Autosave
Microreboot
End-to-end principle
References
External links
https://web.archive.org/web/20060426230247/http://crash.stanford.edu/
Operating system technology
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https://en.wikipedia.org/wiki/JSP%20model%202%20architecture
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JSP Model 2 is a complex design pattern used in the design of Java Web applications which separates the display of content from the logic used to obtain and manipulate the content. Since Model 2 drives a separation between logic and display, it is usually associated with the model–view–controller (MVC) paradigm. While the exact form of the MVC "Model" was never specified by the Model 2 design, a number of publications recommend a formalized layer to contain MVC Model code. The Java BluePrints, for example, originally recommended using EJBs to encapsulate the MVC Model.
In a Model 2 application, requests from the client browser are passed to the controller. The controller performs any logic necessary to obtain the correct content for display. It then places the content in the request (commonly in the form of a JavaBean or POJO) and decides which view it will pass the request to. The view then renders the content passed by the controller.
Model 2 is recommended for medium- and large-sized applications.
History
In 1998, Sun Microsystems published a pre-release of the JavaServer Pages specification, version 0.92. In this specification, Sun laid out two methods by which JSP pages could be used. The first model (referred to as "model 1" due to its ordering in the document) was a simplistic model whereby JSP pages were standalone, disjointed entities. Logic could be contained within the page itself, and navigation between pages was typically achieved by way of hyperlinks. This fit with the then-common usage of template technology.
ColdFusion and Active Server Pages are examples of contemporary technologies that also implemented this model.
The second model referred to by the document ("model 2" in the ordering) was an improved method that combined servlet technology with JSP technology. The specific difference listed was that a servlet would intercept the request, place the content to render into a request attribute (typically represented by a JavaBean), then call a J
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https://en.wikipedia.org/wiki/Opponent%20process
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The opponent process is a color theory that states that the human visual system interprets information about color by processing signals from photoreceptor cells in an antagonistic manner. The opponent-process theory suggests that there are three opponent channels, each comprising an opposing color pair: red versus green, blue versus yellow, and black versus white (luminance). The theory was first proposed in 1892 by the German physiologist Ewald Hering.
Color theory
Complementary colors
When staring at a bright color for a while (e.g. red), then looking away at a white field, an afterimage is perceived, such that the original color will evoke its complementary color (green, in the case of red input). When complementary colors are combined or mixed, they "cancel each other out" and become neutral (white or gray). That is, complementary colors are never perceived as a mixture; there is no "greenish red" or "yellowish blue", despite claims to the contrary. The strongest color contrast a color can have is its complementary color. Complementary colors may also be called "opposite colors" and are understandably the basis of the colors used in the opponent process theory.
Unique hues
The colors that define the extremes for each opponent channel are called unique hues, as opposed to composite (mixed) hues. Ewald Hering first defined the unique hues as red, green, blue, and yellow, and based them on the concept that these colors could not be simultaneously perceived. For example, a color cannot appear both red and green. These definitions have been experimentally refined and are represented today by average hue angles of 353° (carmine-red), 128° (cobalt green), 228° (cobalt blue), 58° (yellow).
Unique hues can differ between individuals and are often used in psychophysical research to measure variations in color perception due to color-vision deficiencies or color adaptation. While there is considerable inter-subject variability when defining unique hues experimentall
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https://en.wikipedia.org/wiki/Hang-On
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is an arcade racing game released by Sega in 1985 and later ported to the Master System. In the game, the player controls a motorcycle against time and other computer-controlled bikes. It was one of the first arcade games to use 16-bit graphics and uses the Super Scaler arcade system board, created with design input from Yu Suzuki, as technology to simulate 3D effects. The deluxe cabinet version also introduced a motion-controlled arcade cabinet, where the player's body movement on a large motorbike-shaped cabinet corresponds with the player character's movements on screen.
Yu Suzuki began development of Hang-On after deciding to design a motorcycle racing game as a way to use a torsion bar in an arcade game. With market research suggesting GP 500 racing was popular, Suzuki took inspiration from world champion Freddie Spencer and his style of racing. The game's soundtrack was written by Hiroshi Kawaguchi, who used rock music that was uncommon in arcade games at the time.
Hang-On was very popular at launch and sold well for Sega, becoming the highest-grossing arcade video game of 1985 in the United States and then the highest-grossing arcade game of 1986 in both Japan and the United States. It received a positive critical reception for its realism, graphics, bike cabinet and physical controls, though there was some initial controversy in Japan over modesty concerns involving female players with the bike cabinet. The game started the trend of "taiken" motion simulator games in the late 1980s, which Sega followed with hits such as Space Harrier (1985), Out Run (1986), and After Burner (1987); this helped the arcade video game market recover during the late 1980s. Hang-On has been recognized as a well-remembered and influential arcade game. Several sequels were later made for arcades, as well as video game consoles.
Gameplay
Using a behind the motorcycle perspective, the player races a linear race track divided into several stages within a limited time. Players h
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https://en.wikipedia.org/wiki/Drive%20by%20wire
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Drive by wire or DbW technology in the automotive industry is the use of electronic or electro-mechanical systems in place of mechanical linkages that control driving functions. The concept is similar to fly-by-wire in the aviation industry. Drive-by-wire may refer to just the propulsion of the vehicle through electronic throttle control, or it may refer to electronic control over propulsion as well as steering and braking, which separately are known as steer by wire and brake by wire, along with electronic control over other vehicle driving functions.
Driver input is traditionally transferred mechanically to the motor and wheels through a steering wheel and steering column, throttle, hydraulic brakes, brake pull handles and so on. In drive-by-wire systems, driver input is processed by an electronic control system which controls the vehicle using electromechanical actuators. The human–machine interface, such as a steering wheel, yoke, accelerator pedal, brake pedal, and so on, may include haptic feedback that simulates the resistance of hydraulic and mechanical pedals and steering, including steering kickback. Components such as the steering column, intermediate shafts, pumps, hoses, belts, coolers, vacuum servos and master cylinders are eliminated from the vehicle. Safety standards for drive-by-wire are specified by the ISO 26262 standard level D.
Properties
Dispensing with mechanical linkages has several advantages: it reduces complexity and simplifies assembly; simplifies service and tuning; reduces the force required to engage inputs and allows it to be customized with haptic technology; allows for more interior design freedom in the placement of input mechanisms; allows for automation of driving functions; reduces cabin noise by eliminating the acoustic linkage to the drive systems; and by reducing floor openings it improves the crash behavior of the vehicle. Because driver inputs can be overridden, safety can be improved by providing computer controlled in
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https://en.wikipedia.org/wiki/Reticular%20cell
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A reticular cell is a type of fibroblast that synthesizes collagen alpha-1(III) and uses it to produce reticular fibers. The cell surrounds the fibers with its cytoplasm, isolating them from other tissue components and cells. Reticular cells provide structural support, since they produce and maintain the thin networks of fibers that are a framework for most lymphoid organs.
Reticular cells are found in many organs, including the spleen, lymph nodes and kidneys. They are also found within tissues, such as lymph nodules. There are different types of reticular cells, including epithelial, mesenchymal, and fibroblastic reticular cells. Fibroblastic reticular cells are involved in directing B cells and T cells to specific regions within the tissue whereas epithelial and mesenchymal reticular cells are associated with certain areas of the brain.
See also
List of human cell types derived from the germ layers
References
2. Schat, K. A., Kaspers, B., & Kaiser, P. (2014). Structure of the Avian Lymphoid System. In I. Olah, N. Nagy & L. Vervelde (Eds.), Avian Immunology (2nd ed., pp. 11-44). Academic Press.
Cell biology
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https://en.wikipedia.org/wiki/Reflection%20symmetry
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In mathematics, reflection symmetry, line symmetry, mirror symmetry, or mirror-image symmetry is symmetry with respect to a reflection. That is, a figure which does not change upon undergoing a reflection has reflectional symmetry.
In 2D there is a line/axis of symmetry, in 3D a plane of symmetry. An object or figure which is indistinguishable from its transformed image is called mirror symmetric. In conclusion, a line of symmetry splits the shape in half and those halves should be identical.
Symmetric function
In formal terms, a mathematical object is symmetric with respect to a given operation such as reflection, rotation or translation, if, when applied to the object, this operation preserves some property of the object. The set of operations that preserve a given property of the object form a group. Two objects are symmetric to each other with respect to a given group of operations if one is obtained from the other by some of the operations (and vice versa).
The symmetric function of a two-dimensional figure is a line such that, for each perpendicular constructed, if the perpendicular intersects the figure at a distance 'd' from the axis along the perpendicular, then there exists another intersection of the shape and the perpendicular, at the same distance 'd' from the axis, in the opposite direction along the perpendicular.
Another way to think about the symmetric function is that if the shape were to be folded in half over the axis, the two halves would be identical: the two halves are each other's mirror images.
Thus a square has four axes of symmetry, because there are four different ways to fold it and have the edges all match. A circle has infinitely many axes of symmetry.
Symmetric geometrical shapes
Triangles with reflection symmetry are isosceles. Quadrilaterals with reflection symmetry are kites, (concave) deltoids, rhombi, and isosceles trapezoids. All even-sided polygons have two simple reflective forms, one with lines of reflections through
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https://en.wikipedia.org/wiki/WBBM-TV
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WBBM-TV (channel 2) is a television station in Chicago, Illinois, United States, serving as the market's CBS network outlet. Owned and operated by the network's CBS News and Stations division, the station maintains studios on West Washington Street in the Loop, and its transmitter is located atop the Willis Tower.
History
Early history (1940–1953)
WBBM-TV traces its history to 1940 when Balaban and Katz, a subsidiary of Paramount Pictures, signed on experimental station W9XBK, the first all-electronic television facility in Chicago. Balaban and Katz was already well known for owning several movie theaters in the Chicago area. In order to establish the station, the company hired television pioneer William C. "Bill" Eddy away from RCA's experimental station W2XBS in New York City. When World War II began, Eddy used the W9XBK facilities as a prototype school for training Navy electronics technicians. While operating the Navy school, Eddy continued to lead W9XBK and wrote a book that defined commercial television for many years.
On September 6, 1946, the station received a commercial license as WBKB (for Balaban and Katz Broadcasting) on VHF channel 4, becoming the first commercial station located outside the Eastern Time Zone; it was also the sixth commercial TV station in the United States behind WNBT (now WNBC), WCBW (now WCBS-TV), WABD (now WNYW) all in New York City; WRGB in Schenectady, New York; and WPTZ (now KYW-TV) in Philadelphia. WBKB aired some of the earliest CBS programs, including the 1947 debut of Junior Jamboree (later renamed Kukla, Fran and Ollie after it moved to NBC in 1948). Channel 4 originally operated as an independent station, since at the time it was not clear that it would be an affiliate of either CBS or the DuMont Television Network; eventually, KSD-TV (now KSDK) in St. Louis became the first television station west of the Eastern Time Zone to affiliate with a major network. One of the station's early highlights was its telecast of the N
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https://en.wikipedia.org/wiki/Iiyama%20%28company%29
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iiyama is a brand name of . It produces liquid crystal display (LCD) monitors and LED display panels. It was previously an independent Japanese computer electronics company called with its headquarters in Chiyoda-ku, Tokyo. Iiyama was founded in 1972 by Kazuro Katsuyama, named after the city of Iiyama in Nagano Prefecture, Japan. The company was bought in January 2006 by MCJ Corporation, which includes Mouse Computer Corporation. The headquarters of iiyama was moved to Europe in October 2008. The CEO since January 2006 has been Takeichi Shinji.
History
Founded in March 1972 as by 23-year-old bank employee Kazuro Katsuyama, it first started manufacturing television boards and substrates for Mitsubishi at a local plant in Nagano Prefecture. They started producing black and white TVs in 1976 and color TVs in 1979, followed by computer monitors under its own brand name in 1981 which then became its main product range.
The company expanded to the western market in 1987 and in the 1990s opened up offices in Philadelphia, Germany, Poland, France, UK, Sweden, the Czech Republic, Taiwan, and its international head office in the Netherlands, where it is registered as Iiyama Benelux B.V. By 1993 it was the leading monitor supplier in Japan with a 21% market share. The first LCDs were released by iiyama in 1997.
In 2001 it merged with e-yama to create , and its headquarters moved to Nagano City. In 2006 holding company bought Iiyama and renamed it to , moving its base to Chūō, Tokyo. In October 2008 iiyama Corporation became part of Mouse Computer Co., Ltd., one of MCJ's companies.
See also
Iiyama Vision Master Pro series
References
External links
Computer companies established in 1972
Electronics companies established in 1972
Display technology companies
Electronics companies of Japan
Computer companies of Japan
Manufacturing companies based in Tokyo
Japanese brands
Iiyama
Japanese companies established in 1972
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https://en.wikipedia.org/wiki/List%20of%20unsolved%20problems%20in%20neuroscience
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There are yet unsolved problems in neuroscience, although some of these problems have evidence supporting a hypothesized solution, and the field is rapidly evolving. One major problem is even enumerating what would belong on a list such as this. However, these problems include:
Consciousness
Consciousness:
How can consciousness be defined?
What is the neural basis of subjective experience, cognition, wakefulness, alertness, arousal, and attention?
Quantum mind: Does quantum mechanical phenomena, such as entanglement and superposition, play an important part in the brain's function and can it explain critical aspects of consciousness?
Is there a "hard problem of consciousness"?
If so, how is it solved?
What, if any, is the function of consciousness?
What is the nature and mechanism behind near-death experiences?
How can death be defined? Can consciousness exist after death?
If consciousness is generated by brain activity, then how do some patients with physically deteriorated brains suddenly gain a brief moment of restored consciousness prior to death, a phenomenon known as terminal lucidity?
Problem of representation: How exactly does the mind function (or how does the brain interpret and represent information about the world)?
Bayesian mind: Does the mind make sense of the world by constantly trying to make predictions according to the rules of Bayesian probability?
Computational theory of mind: Is the mind a symbol manipulation system, operating on a model of computation, similar to a computer?
Connectionism: Can the mind be explained by mathematical models known as artificial neural networks?
Embodied cognition: Is the cognition of an organism affected by the organism's entire body (rather than just simply its brain), including its interactions with the environment?
Extended mind thesis: Does the mind not only exist in the brain, but also functions in the outside world by using physical objects as mental processes? Or just as prosthetic limbs can becom
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https://en.wikipedia.org/wiki/Interplanetary%20Internet
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The interplanetary Internet is a conceived computer network in space, consisting of a set of network nodes that can communicate with each other. These nodes are the planet's orbiters and landers, and the Earth ground stations. For example, the orbiters collect the scientific data from the Curiosity rover on Mars through near-Mars communication links, transmit the data to Earth through direct links from the Mars orbiters to the Earth ground stations, and finally the data routed through Earth's internal internet.
Interplanetary communication is greatly delayed by interplanetary distances, so a new set of protocols and technologies that are tolerant to large delays and errors are required. The interplanetary Internet is a store and forward network of internets that is often disconnected, has a wireless backbone fraught with error-prone links and delays ranging from tens of minutes to even hours, even when there is a connection.
Challenges and reasons
In the core implementation of Interplanetary Internet, satellites orbiting a planet communicate to other planet's satellites. Simultaneously, these planets revolve around the Sun with long distances, and thus many challenges face the communications. The reasons and the resultant challenges are:
The motion and long distances between planets: The interplanetary communication is greatly delayed due to the interplanetary distances and the motion of the planets. The delay is variable and long, ranges from a couple of minutes (Earth-to-Mars), to a couple of hours (Pluto-to-Earth), depending on their relative positions. The interplanetary communication also suspends due to the solar conjunction, when the sun's radiation hinders the direct communication between the planets. As such, the communication characterizes lossy links and intermittent link connectivity.
Low embeddable payload: Satellites can only carry a small payload, which poses challenges to the power, mass, size, and cost for communication hardware design. An
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https://en.wikipedia.org/wiki/Orientation%20%28vector%20space%29
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The orientation of a real vector space or simply orientation of a vector space is the arbitrary choice of which ordered bases are "positively" oriented and which are "negatively" oriented. In the three-dimensional Euclidean space, right-handed bases are typically declared to be positively oriented, but the choice is arbitrary, as they may also be assigned a negative orientation. A vector space with an orientation selected is called an oriented vector space, while one not having an orientation selected, is called .
In mathematics, orientability is a broader notion that, in two dimensions, allows one to say when a cycle goes around clockwise or counterclockwise, and in three dimensions when a figure is left-handed or right-handed. In linear algebra over the real numbers, the notion of orientation makes sense in arbitrary finite dimension, and is a kind of asymmetry that makes a reflection impossible to replicate by means of a simple displacement. Thus, in three dimensions, it is impossible to make the left hand of a human figure into the right hand of the figure by applying a displacement alone, but it is possible to do so by reflecting the figure in a mirror. As a result, in the three-dimensional Euclidean space, the two possible basis orientations are called right-handed and left-handed (or right-chiral and left-chiral).
Definition
Let V be a finite-dimensional real vector space and let b1 and b2 be two ordered bases for V. It is a standard result in linear algebra that there exists a unique linear transformation A : V → V that takes b1 to b2. The bases b1 and b2 are said to have the same orientation (or be consistently oriented) if A has positive determinant; otherwise they have opposite orientations. The property of having the same orientation defines an equivalence relation on the set of all ordered bases for V. If V is non-zero, there are precisely two equivalence classes determined by this relation. An orientation on V is an assignment of +1 to one equivale
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https://en.wikipedia.org/wiki/Nob%20Yoshigahara
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Nobuyuki Yoshigahara ( Yoshigahara Nobuyuki, commonly known as "Nob"; May 27, 1936 – June 19, 2004) was perhaps Japan's most celebrated inventor, collector, solver, and communicator of puzzles.
Nob graduated from the Tokyo Institute of Technology in applied chemistry. After becoming disenchanted with his career in high-polymer engineering, Nob turned to high school teaching as an educator of chemistry and mathematics.
As a puzzle columnist, Nob was an active contributor to many journals and had monthly columns in various popular magazines, including Quark. He penned over 80 books on puzzles. Perhaps best known as a puzzle inventor, he commercially licensed his designs, such as the Rush Hour puzzle game, to companies including Binary Arts (now known as ThinkFun), Ishi Press, and Hanayama. He was also an avid computer programmer who used computers to help solve mathematical puzzles.
Nob was an active participant in the International Puzzle Party, traveling the world to attend the annual event. In 2005, the puzzle design competition of the International Puzzle Parties was renamed the Nob Yoshigahara Puzzle Design Competition.
In 2003, the Association of Game & Puzzle Collectors awarded Nob with the Sam Loyd Award, given to individuals who have made a significant contribution to the world of mechanical puzzles.
See also
Puzzle
Mechanical puzzle
Kagen Sound
Nob Yoshigahara Puzzle Design Competition
References
External links
Ed Pegg Jr. Nob Yoshigahara, June 28, 2004.
Example mechanical puzzles by Nob Yoshigahara
Association of Game & Puzzle Collectors
Nob Yoshigahara Puzzle Design Competition
Barry Arthur Cipra, Erik D. Demaine, Marin L. Demaine, and Tom Rodgers. Tribute to a Mathemagician. — A K Peters, 2005. — 262 с. — .
1936 births
2004 deaths
Puzzle designers
Mathematics popularizers
Recreational mathematicians
Tokyo Institute of Technology alumni
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https://en.wikipedia.org/wiki/Catagenesis%20%28biology%29
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Catagenesis is a somewhat archaic term from evolutionary biology referring to evolutionary directions that were considered "retrogressive." It was a term used in contrast to anagenesis, which in present usage denotes the evolution of a single population into a new form without branching lines of descent.
See also
Evolutionary biology
References
Evolutionary biology
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https://en.wikipedia.org/wiki/Stiefel%20manifold
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In mathematics, the Stiefel manifold is the set of all orthonormal k-frames in That is, it is the set of ordered orthonormal k-tuples of vectors in It is named after Swiss mathematician Eduard Stiefel. Likewise one can define the complex Stiefel manifold of orthonormal k-frames in and the quaternionic Stiefel manifold of orthonormal k-frames in . More generally, the construction applies to any real, complex, or quaternionic inner product space.
In some contexts, a non-compact Stiefel manifold is defined as the set of all linearly independent k-frames in or this is homotopy equivalent, as the compact Stiefel manifold is a deformation retract of the non-compact one, by Gram–Schmidt. Statements about the non-compact form correspond to those for the compact form, replacing the orthogonal group (or unitary or symplectic group) with the general linear group.
Topology
Let stand for or The Stiefel manifold can be thought of as a set of n × k matrices by writing a k-frame as a matrix of k column vectors in The orthonormality condition is expressed by A*A = where A* denotes the conjugate transpose of A and denotes the k × k identity matrix. We then have
The topology on is the subspace topology inherited from With this topology is a compact manifold whose dimension is given by
As a homogeneous space
Each of the Stiefel manifolds can be viewed as a homogeneous space for the action of a classical group in a natural manner.
Every orthogonal transformation of a k-frame in results in another k-frame, and any two k-frames are related by some orthogonal transformation. In other words, the orthogonal group O(n) acts transitively on The stabilizer subgroup of a given frame is the subgroup isomorphic to O(n−k) which acts nontrivially on the orthogonal complement of the space spanned by that frame.
Likewise the unitary group U(n) acts transitively on with stabilizer subgroup U(n−k) and the symplectic group Sp(n) acts transitively on with stabilizer subgroup S
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https://en.wikipedia.org/wiki/Atari%20DOS
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Atari DOS is the disk operating system used with the Atari 8-bit family of computers. Operating system extensions loaded into memory were required in order for an Atari computer to manage files stored on a disk drive. These extensions to the operating system added the disk handler and other file management features.
The most important extension is the disk handler. In Atari DOS 2.0, this was the File Management System (FMS), an implementation of a file system loaded from a floppy disk. This meant at least an additional RAM was needed to run with DOS loaded.
Versions
There were several versions of Atari DOS available, with the first version released in 1979. Atari was using a cross assembler with Data General AOS.
DOS 1.0
In the first version of DOS from Atari all commands were only accessible from the menu. It was bundled with the 810 disk drives. This version was entirely memory resident, which made it fast but occupied memory space.
DOS 2.0
Also known as DISK OPERATING SYSTEM II VERSION 2.0S
The second, more popular version of DOS from Atari was bundled with the 810 disk drives and some early 1050 disk drives. It is considered to be the lowest common denominator for Atari DOSes, as any Atari-compatible disk drive can read a disk formatted with DOS 2.0S.
DOS 2.0S consisted of DOS.SYS and DUP.SYS. DOS.SYS was loaded into memory, while DUP.SYS contained the disk utilities and was loaded only when the user exited to DOS.
In addition to bug fixes, DOS 2.0S featured improved NOTE/POINT support and the ability to automatically run an Atari executable file named AUTORUN.SYS. Since user memory was erased when DUP.SYS was loaded, an option to create a MEM.SAV file was added. This stored user memory in a temporary file (MEM.SAV) and restored it after DUP.SYS was unloaded. The previous menu option from DOS 1.0, N. DEFINE DEVICE, was replaced with N. CREATE MEM.SAV in DOS 2.0S.
Version 2.0S was for single-density disks, 2.0D was for double-density disks. 2.0D shipped w
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https://en.wikipedia.org/wiki/ILLIAC
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ILLIAC (Illinois Automatic Computer) was a series of supercomputers built at a variety of locations, some at the University of Illinois at Urbana–Champaign. In all, five computers were built in this series between 1951 and 1974. Some more modern projects also use the name.
Architectural blueprint
The architecture for the first two UIUC computers was taken from a technical report from a committee at the Institute for Advanced Study (IAS) at Princeton, First Draft of a Report on the EDVAC (1945), edited by John von Neumann (but with ideas from Eckert, Mauchley, and many others.) The designs in this report were not tested at Princeton until a later machine, JOHNNIAC, was completed in 1953. However, the technical report was a major influence on computing in the 1950s, and was used as a blueprint for many other computers, including two at the University of Illinois, which were both completed before Princeton finished Johnniac. The University of Illinois was the only institution to build two instances of the IAS machine. In fairness, several of the other universities, including Princeton, invented new technology (new types of memory or I/O devices) during the construction of their computers, which delayed those projects. For ILLIAC I, II, and IV, students associated with IAS at Princeton (Abraham H. Taub, Donald B. Gillies, Daniel Slotnick) played a key role in the computer designs.
ORDVAC
ORDVAC was the first of two computers built under contract at the University of Illinois. ORDVAC was completed the spring of 1951 and checked out in the summer. In the fall it was delivered to the US Army's Aberdeen Proving Grounds and was checked out in roughly one week. As part of the contract, funds were provided to the University of Illinois to build a second identical computer known as ILLIAC I.
ILLIAC I
ILLIAC I was built at the University of Illinois based on the same design as the ORDVAC. It was the first von Neumann architecture computer built and owned by an America
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