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https://en.wikipedia.org/wiki/Convergent%20evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is ho...
https://en.wikipedia.org/wiki/Data%20model
A data model is an abstract model that organizes elements of data and standardizes how they relate to one another and to the properties of real-world entities. For instance, a data model may specify that the data element representing a car be composed of a number of other elements which, in turn, represent the color an...
https://en.wikipedia.org/wiki/Homo%20economicus
The term Homo economicus, or economic man, is the portrayal of humans as agents who are consistently rational and narrowly self-interested, and who pursue their subjectively defined ends optimally. It is a word play on Homo sapiens, used in some economic theories and in pedagogy. In game theory, Homo economicus is oft...
https://en.wikipedia.org/wiki/Magnetometer
A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, one that measures the direction of an ambient magnetic field, in this case, ...
https://en.wikipedia.org/wiki/Intermediate%20frequency
In communications and electronic engineering, an intermediate frequency (IF) is a frequency to which a carrier wave is shifted as an intermediate step in transmission or reception. The intermediate frequency is created by mixing the carrier signal with a local oscillator signal in a process called heterodyning, resulti...
https://en.wikipedia.org/wiki/United%20States%20Army%20Corps%20of%20Engineers
The United States Army Corps of Engineers (USACE) is an engineer formation of the United States Army that has three primary mission areas: Engineer Regiment, military construction, and civil works. The day-to-day activities of the three mission areas are administered by a lieutenant general known as the commanding gene...
https://en.wikipedia.org/wiki/Open%20Archives%20Initiative
The Open Archives Initiative (OAI) was an informal organization, in the circle around the colleagues Herbert Van de Sompel, Carl Lagoze, Michael L. Nelson and Simeon Warner, to develop and apply technical interoperability standards for archives to share catalogue information (metadata). The group got together in the la...
https://en.wikipedia.org/wiki/Cybersex
Cybersex, also called computer sex, Internet sex, netsex and, colloquially, cyber or cybering, is a virtual sex encounter in which two or more people have long distance sex via electronic video communication (webcams, VR headsets, etc) and other electronics (such as teledildonics) connected to a computer network. Cybe...
https://en.wikipedia.org/wiki/Mother%20of%20vinegar
Mother of vinegar is a biofilm composed of a form of cellulose, yeast, and bacteria that sometimes develops on fermenting alcoholic liquids during the process that turns alcohol into acetic acid with the help of oxygen from the air and acetic acid bacteria (AAB). It is similar to the symbiotic culture of bacteria and y...
https://en.wikipedia.org/wiki/Subsumption%20architecture
Subsumption architecture is a reactive robotic architecture heavily associated with behavior-based robotics which was very popular in the 1980s and 90s. The term was introduced by Rodney Brooks and colleagues in 1986. Subsumption has been widely influential in autonomous robotics and elsewhere in real-time AI. Overv...
https://en.wikipedia.org/wiki/Geocentric%20model
In astronomy, the geocentric model (also known as geocentrism, often exemplified specifically by the Ptolemaic system) is a superseded description of the Universe with Earth at the center. Under most geocentric models, the Sun, Moon, stars, and planets all orbit Earth. The geocentric model was the predominant descripti...
https://en.wikipedia.org/wiki/Earth%20Simulator
The is a series of supercomputers deployed at Japan Agency for Marine-Earth Science and Technology Yokohama Institute of Earth Sciences. Earth Simulator (first generation) The first generation of Earth Simulator, developed by the Japanese government's initiative "Earth Simulator Project", was a highly parallel vect...
https://en.wikipedia.org/wiki/Euclidean%20planes%20in%20three-dimensional%20space
In Euclidean geometry, a plane is a flat two-dimensional surface that extends indefinitely. Euclidean planes often arise as subspaces of three-dimensional space . A prototypical example is one of a room's walls, infinitely extended and assumed infinitesimal thin. While a pair of real numbers suffices to describe poin...
https://en.wikipedia.org/wiki/Ingres%20%28database%29
Ingres Database ( ) is a proprietary SQL relational database management system intended to support large commercial and government applications. Actian Corporation, which announced April 2018 that it is being acquired by HCL Technologies, controls the development of Ingres and makes certified binaries available for do...
https://en.wikipedia.org/wiki/Zero-point%20energy
Zero-point energy (ZPE) is the lowest possible energy that a quantum mechanical system may have. Unlike in classical mechanics, quantum systems constantly fluctuate in their lowest energy state as described by the Heisenberg uncertainty principle. Therefore, even at absolute zero, atoms and molecules retain some vibrat...
https://en.wikipedia.org/wiki/Xenix
Xenix is a discontinued version of the Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation in the late 1970s. The Santa Cruz Operation (SCO) later acquired exclusive rights to the software, and eventually replaced it with SCO UNIX (now known as SCO OpenServer). In the...
https://en.wikipedia.org/wiki/Dead%20code
The term dead code has multiple definitions. Some use the term to refer to code (i.e. instructions in memory) which can never be executed at run-time. In some areas of computer programming, dead code is a section in the source code of a program which is executed but whose result is never used in any other computation. ...
https://en.wikipedia.org/wiki/Cargo%20cult%20programming
Cargo cult programming is a style of computer programming characterized by the ritual inclusion of code or program structures that serve no real purpose. Cargo cult programming is symptomatic of a programmer not understanding either a bug they were attempting to solve or the apparent solution (compare shotgun debugging...
https://en.wikipedia.org/wiki/Toma%C5%BE%20Pisanski
Tomaž (Tomo) Pisanski (born 24 May 1949 in Ljubljana, Yugoslavia, which is now in Slovenia) is a Slovenian mathematician working mainly in discrete mathematics and graph theory. He is considered by many Slovenian mathematicians to be the "father of Slovenian discrete mathematics." Biography As a high school student, P...
https://en.wikipedia.org/wiki/Logistic%20function
A logistic function or logistic curve is a common S-shaped curve (sigmoid curve) with the equation where For values of in the domain of real numbers from to , the S-curve shown on the right is obtained, with the graph of approaching as approaches and approaching zero as approaches . The logistic function find...
https://en.wikipedia.org/wiki/Hubbert%20curve
The Hubbert curve is an approximation of the production rate of a resource over time. It is a symmetric logistic distribution curve, often confused with the "normal" gaussian function. It first appeared in "Nuclear Energy and the Fossil Fuels," geologist M. King Hubbert's 1956 presentation to the American Petroleum ...
https://en.wikipedia.org/wiki/Timeline%20of%20computing%20hardware%20before%201950
This article presents a detailed timeline of events in the history of computing software and hardware: from prehistory until 1949. For narratives explaining the overall developments, see History of computing. Prehistory–antiquity Medieval–1640 1641–1850 1851–1930 1931–1940 1941–1949 Computing timeline Timeline o...
https://en.wikipedia.org/wiki/Network%20layer
In the seven-layer OSI model of computer networking, the network layer is layer 3. The network layer is responsible for packet forwarding including routing through intermediate routers. Functions The network layer provides the means of transferring variable-length network packets from a source to a destination host vi...
https://en.wikipedia.org/wiki/High%20pressure
In science and engineering the study of high pressure examines its effects on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By high pressure is usually meant pressures of thousands (kilobars) or millions (megabars) of times atmospheric pressure (abou...
https://en.wikipedia.org/wiki/Man%20page
A man page (short for manual page) is a form of software documentation usually found on a Unix or Unix-like operating system. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts. A user may invoke a man page by issuing the man comma...
https://en.wikipedia.org/wiki/IA-64
IA-64 (Intel Itanium architecture) is the instruction set architecture (ISA) of the discontinued Itanium family of 64-bit Intel microprocessors. The basic ISA specification originated at Hewlett-Packard (HP), and was subsequently implemented by Intel in collaboration with HP. The first Itanium processor, codenamed Merc...
https://en.wikipedia.org/wiki/Great%20Renaming
The Great Renaming was a restructuring of Usenet newsgroups that took place in 1987. B News maintainer and UUNET founder Rick Adams is generally considered to be the initiator of the Renaming. Motivation The primary reason for the Great Renaming was said to be the difficulty of maintaining a list of all the existing ...
https://en.wikipedia.org/wiki/Lah%20number
In mathematics, the (signed and unsigned) Lah numbers are coefficients expressing rising factorials in terms of falling factorials and vice versa. They were discovered by Ivo Lah in 1954. Explicitly, the unsigned Lah numbers are given by the formula involving the binomial coefficient for . Unsigned Lah numbers ha...
https://en.wikipedia.org/wiki/Penet%20remailer
The Penet remailer () was a pseudonymous remailer operated by Johan "Julf" Helsingius of Finland from 1993 to 1996. Its initial creation stemmed from an argument in a Finnish newsgroup over whether people should be required to tie their real name to their online communications. Julf believed that people should not—inde...
https://en.wikipedia.org/wiki/Pseudonymous%20remailer
A pseudonymous remailer or nym server, as opposed to an anonymous remailer, is an Internet software program designed to allow people to write pseudonymous messages on Usenet newsgroups and send pseudonymous email. Unlike purely anonymous remailers, it assigns its users a user name, and it keeps a database of instructi...
https://en.wikipedia.org/wiki/PSOS%20%28real-time%20operating%20system%29
pSOS (Portable Software On Silicon) is a real-time operating system (RTOS), created in about 1982 by Alfred Chao, and developed and marketed for the first part of its life by his company Software Components Group (SCG). In the 1980s, pSOS rapidly became the RTOS of choice for all embedded systems based on the Motorola ...
https://en.wikipedia.org/wiki/Winding%20number
In mathematics, the winding number or winding index of a closed curve in the plane around a given point is an integer representing the total number of times that curve travels counterclockwise around the point, i.e., the curve's number of turns. For certain open plane curves, the number of turns may be non-integer. The...
https://en.wikipedia.org/wiki/Pike%20%28programming%20language%29
Pike is an interpreted, general-purpose, high-level, cross-platform, dynamic programming language, with a syntax similar to that of C. Unlike many other dynamic languages, Pike is both statically and dynamically typed, and requires explicit type definitions. It features a flexible type system that allows the rapid deve...
https://en.wikipedia.org/wiki/GE-200%20series
The GE-200 series was a family of small mainframe computers of the 1960s, built by General Electric (GE). GE marketing called the line Compatibles/200 (GE-205/215/225/235). The GE-210 of 1960 was not compatible with the rest of the 200 series. 200 series models The main machine in the line was the GE-225 (1961). It u...
https://en.wikipedia.org/wiki/Malleability%20%28cryptography%29
Malleability is a property of some cryptographic algorithms. An encryption algorithm is "malleable" if it is possible to transform a ciphertext into another ciphertext which decrypts to a related plaintext. That is, given an encryption of a plaintext , it is possible to generate another ciphertext which decrypts to , f...
https://en.wikipedia.org/wiki/International%20Association%20for%20Cryptologic%20Research
The International Association for Cryptologic Research (IACR) is a non-profit scientific organization that furthers research in cryptology and related fields. The IACR was organized at the initiative of David Chaum at the CRYPTO '82 conference. Activities The IACR organizes and sponsors three annual flagship conferenc...
https://en.wikipedia.org/wiki/Snake%20lemma
The snake lemma is a tool used in mathematics, particularly homological algebra, to construct long exact sequences. The snake lemma is valid in every abelian category and is a crucial tool in homological algebra and its applications, for instance in algebraic topology. Homomorphisms constructed with its help are gener...
https://en.wikipedia.org/wiki/Connectedness
In mathematics, connectedness is used to refer to various properties meaning, in some sense, "all one piece". When a mathematical object has such a property, we say it is connected; otherwise it is disconnected. When a disconnected object can be split naturally into connected pieces, each piece is usually called a comp...
https://en.wikipedia.org/wiki/Herd%20immunity
Herd immunity (also called herd effect, community immunity, population immunity, or mass immunity) is a form of indirect protection that applies only to contagious diseases. It occurs when a sufficient percentage of a population has become immune to an infection, whether through previous infections or vaccination, ther...
https://en.wikipedia.org/wiki/Closed-circuit%20television
Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly transmitted, though it may employ point-to-point (P2P), point-to-multipoint (P2MP)...
https://en.wikipedia.org/wiki/Coda%20%28file%20system%29
Coda is a distributed file system developed as a research project at Carnegie Mellon University since 1987 under the direction of Mahadev Satyanarayanan. It descended directly from an older version of Andrew File System (AFS-2) and offers many similar features. The InterMezzo file system was inspired by Coda. Features...
https://en.wikipedia.org/wiki/Commodore%20PET
The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, and, in early models, a cassette deck. Development of the system began in 19...
https://en.wikipedia.org/wiki/Heaviside%20step%20function
The Heaviside step function, or the unit step function, usually denoted by or (but sometimes , or ), is a step function named after Oliver Heaviside, the value of which is zero for negative arguments and one for positive arguments. It is an example of the general class of step functions, all of which can be represen...
https://en.wikipedia.org/wiki/Graph%20of%20a%20function
In mathematics, the graph of a function is the set of ordered pairs , where In the common case where and are real numbers, these pairs are Cartesian coordinates of points in two-dimensional space and thus form a subset of this plane. In the case of functions of two variables, that is functions whose domain consist...
https://en.wikipedia.org/wiki/GEM%20%28desktop%20environment%29
GEM (for Graphics Environment Manager) is a discontinued operating environment released by Digital Research in 1985. GEM is known primarily as the native graphical user interface of the Atari ST series of computers, providing a WIMP desktop. It was also available for IBM PC compatibles and shipped with some models from...
https://en.wikipedia.org/wiki/Web%20%28programming%20system%29
Web is a computer programming system created by Donald E. Knuth as the first implementation of what he called "literate programming": the idea that one could create software as works of literature, by embedding source code inside descriptive text, rather than the reverse (as is common practice in most programming langu...
https://en.wikipedia.org/wiki/ChatZilla
ChatZilla is an IRC client that is part of SeaMonkey. It was previously an extension for Mozilla-based browsers such as Firefox, introduced in 2000. It is cross-platform open source software which has been noted for its consistent appearance across platforms, CSS appearance customization and scripting. Early history O...
https://en.wikipedia.org/wiki/ISCSI
Internet Small Computer Systems Interface or iSCSI ( ) is an Internet Protocol-based storage networking standard for linking data storage facilities. iSCSI provides block-level access to storage devices by carrying SCSI commands over a TCP/IP network. iSCSI facilitates data transfers over intranets and to manage storag...
https://en.wikipedia.org/wiki/Coral%20reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes...
https://en.wikipedia.org/wiki/G.%20H.%20Hardy
Godfrey Harold Hardy (7 February 1877 – 1 December 1947) was an English mathematician, known for his achievements in number theory and mathematical analysis. In biology, he is known for the Hardy–Weinberg principle, a basic principle of population genetics. G. H. Hardy is usually known by those outside the field of m...
https://en.wikipedia.org/wiki/MP/M
MP/M (Multi-Programming Monitor Control Program) is a discontinued multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each using a separate terminal. MP/M was a fairly advanced operating system for its ...
https://en.wikipedia.org/wiki/Joseph-Louis%20Lagrange
Joseph-Louis Lagrange (born Giuseppe Luigi Lagrangia or Giuseppe Ludovico De la Grange Tournier; 25 January 1736 – 10 April 1813), also reported as Giuseppe Luigi Lagrange or Lagrangia, was an Italian mathematician, physicist and astronomer, later naturalized French. He made significant contributions to the fields of a...
https://en.wikipedia.org/wiki/Cornucopia
In classical antiquity, the cornucopia (), from Latin cornu (horn) and copia (abundance), also called the horn of plenty, was a symbol of abundance and nourishment, commonly a large horn-shaped container overflowing with produce, flowers, or nuts. Baskets or panniers of this form were traditionally used in western Asi...
https://en.wikipedia.org/wiki/Ratio
In mathematics, a ratio () shows how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8:6, which is equivalent to the ratio 4:3). Similarly, the ratio of lemons to oranges is 6:8 (or 3:4) and ...
https://en.wikipedia.org/wiki/Sharkovskii%27s%20theorem
In mathematics, Sharkovskii's theorem (also spelled Sharkovsky's theorem, Sharkovskiy's theorem, Šarkovskii's theorem or Sarkovskii's theorem), named after Oleksandr Mykolayovych Sharkovsky, who published it in 1964, is a result about discrete dynamical systems. One of the implications of the theorem is that if a disc...
https://en.wikipedia.org/wiki/Syllable%20Desktop
Syllable Desktop is a discontinued free and open-source operating system for Pentium and compatible processors. Its purpose is to create an easy-to-use desktop operating system for the home and small office user. It was forked from the stagnant AtheOS in July 2002. It has a native web browser (Webster, which is WebKit...
https://en.wikipedia.org/wiki/Dual-ported%20RAM
Dual-ported RAM (DPRAM) is a type of random-access memory that allows multiple reads or writes to occur at the same time, or nearly the same time, unlike single-ported RAM which allows only one access at a time. Examples Video RAM (VRAM) is a common form of dual-ported dynamic RAM mostly used for video memory, allowin...
https://en.wikipedia.org/wiki/Lattice%20C
The Lattice C Compiler was released in June 1982 by Lifeboat Associates and was the first C compiler for the IBM Personal Computer. The compiler sold for $500 and would run on PC DOS or MS-DOS (which at the time were the same product with different brandings). The first hardware requirements were given as 96KB of RAM a...
https://en.wikipedia.org/wiki/AppleScript
AppleScript is a scripting language created by Apple Inc. that facilitates automated control over scriptable Mac applications. First introduced in System 7, it is currently included in all versions of macOS as part of a package of system automation tools. The term "AppleScript" may refer to the language itself, to an i...
https://en.wikipedia.org/wiki/Phosphor
A phosphor is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy. The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or visible light, and cathodoluminescent substances which glow when struck by an e...
https://en.wikipedia.org/wiki/Internet%20Oracle
The Internet Oracle (historically known as The Usenet Oracle) is an effort at collective humor in a pseudo-Socratic question-and-answer format. A user sends a question ("tellme") to the Oracle via e-mail, or the Internet Oracle website, and it is sent to another user (another "incarnation" of the Oracle) who may answe...
https://en.wikipedia.org/wiki/Skywarn
Skywarn (sometimes stylized as SKYWARN) is a program of the National Weather Service (NWS). Its mission is to collect reports of localized severe weather in the United States. These reports are used to aid forecasters in issuing and verifying severe weather watches and warnings and to improve the forecasting and warnin...
https://en.wikipedia.org/wiki/Metronome
A metronome () is a device that produces an audible click or other sound at a regular interval that can be set by the user, typically in beats per minute (BPM). Metronomes may include synchronized visual motion. Musicians use the device to practise playing to a regular pulse. A kind of metronome was among the inventio...
https://en.wikipedia.org/wiki/Improvisation
Improvisation, often shortened to improv, is the activity of making or doing something not planned beforehand, using whatever can be found. The origin of the word itself, is in the Latin 'improvisus', which literally means un-foreseen. But it is also related to both the old French word 'emprouer' and the English 'impro...
https://en.wikipedia.org/wiki/AmigaDOS
AmigaDOS is the disk operating system of the AmigaOS, which includes file systems, file and directory manipulation, the command-line interface, and file redirection. In AmigaOS 1.x, AmigaDOS is based on a TRIPOS port by MetaComCo, written in BCPL. BCPL does not use native pointers, so the more advanced functionality o...
https://en.wikipedia.org/wiki/Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3CHO, sometimes abbreviated as MeCHO. It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Ace...
https://en.wikipedia.org/wiki/5-Methylcytosine
5-Methylcytosine is a methylated form of the DNA base cytosine (C) that regulates gene transcription and takes several other biological roles. When cytosine is methylated, the DNA maintains the same sequence, but the expression of methylated genes can be altered (the study of this is part of the field of epigenetics). ...
https://en.wikipedia.org/wiki/Gene%20knockout
Gene knockouts (also known as gene deletion or gene inactivation) are a widely used genetic engineering technique that involves the targeted removal or inactivation of a specific gene within an organism's genome. This can be done through a variety of methods, including homologous recombination, CRISPR-Cas9, and TALENs....
https://en.wikipedia.org/wiki/Curve
In mathematics, a curve (also called a curved line in older texts) is an object similar to a line, but that does not have to be straight. Intuitively, a curve may be thought of as the trace left by a moving point. This is the definition that appeared more than 2000 years ago in Euclid's Elements: "The [curved] line is...
https://en.wikipedia.org/wiki/Greedy%20algorithm
A greedy algorithm is any algorithm that follows the problem-solving heuristic of making the locally optimal choice at each stage. In many problems, a greedy strategy does not produce an optimal solution, but a greedy heuristic can yield locally optimal solutions that approximate a globally optimal solution in a reason...
https://en.wikipedia.org/wiki/Banner
A banner can be a flag or another piece of cloth bearing a symbol, logo, slogan or another message. A flag whose design is the same as the shield in a coat of arms (but usually in a square or rectangular shape) is called a banner of arms. Also, a bar-shaped piece of non-cloth advertising material sporting a name, sloga...
https://en.wikipedia.org/wiki/Combinational%20logic
In automata theory, combinational logic (also referred to as time-independent logic or combinatorial logic) is a type of digital logic which is implemented by Boolean circuits, where the output is a pure function of the present input only. This is in contrast to sequential logic, in which the output depends not only on...
https://en.wikipedia.org/wiki/Sequential%20logic
In automata theory, sequential logic is a type of logic circuit whose output depends on the present value of its input signals and on the sequence of past inputs, the input history. This is in contrast to combinational logic, whose output is a function of only the present input. That is, sequential logic has state (me...
https://en.wikipedia.org/wiki/Trillian%20%28software%29
Trillian is a proprietary multiprotocol instant messaging application created by Cerulean Studios. It is currently available for Microsoft Windows, Mac OS X, Linux, Android, iOS, BlackBerry OS, and the Web. It can connect to multiple IM services, such as AIM, Bonjour, Facebook Messenger, Google Talk (Hangouts), IRC, XM...
https://en.wikipedia.org/wiki/Arrow%27s%20impossibility%20theorem
Arrow's impossibility theorem, the general possibility theorem or Arrow's paradox is an impossibility theorem in social choice theory that states that when voters have three or more distinct alternatives (options), no ranked voting electoral system can convert the ranked preferences of individuals into a community-wide...
https://en.wikipedia.org/wiki/Inequation
In mathematics, an inequation is a statement that an inequality holds between two values. It is usually written in the form of a pair of expressions denoting the values in question, with a relational sign between them indicating the specific inequality relation. Some examples of inequations are: In some cases...
https://en.wikipedia.org/wiki/Inequality%20%28mathematics%29
In mathematics, an inequality is a relation which makes a non-equal comparison between two numbers or other mathematical expressions. It is used most often to compare two numbers on the number line by their size. There are several different notations used to represent different kinds of inequalities: The notation a < ...
https://en.wikipedia.org/wiki/Antikythera%20mechanism
The Antikythera mechanism ( ) is an Ancient Greek hand-powered orrery (model of the Solar System), described as the oldest known example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games which was similar ...
https://en.wikipedia.org/wiki/Screensaver
A screensaver (or screen saver) is a computer program that blanks the display screen or fills it with moving images or patterns when the computer has been idle for a designated time. The original purpose of screensavers was to prevent phosphor burn-in on CRT or plasma computer monitors (hence the name). Though most mod...
https://en.wikipedia.org/wiki/Mitochondrial%20DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA is only a small portion of the DNA in a eukaryotic cell; most of the DNA can be...
https://en.wikipedia.org/wiki/List%20of%20environmental%20issues
This is an alphabetical list of environmental issues, harmful aspects of human activity on the biophysical environment. They are loosely divided into causes, effects and mitigation, noting that effects are interconnected and can cause new effects. Issues Greenhouse gas emissions — Coal-fired power station • Carbon di...
https://en.wikipedia.org/wiki/Motorola%2056000
The Motorola DSP56000 (also known as 56K) is a family of digital signal processor (DSP) chips produced by Motorola Semiconductor (later Freescale Semiconductor then NXP) starting in 1986 with later models are still being produced in the 2020s. The 56k series was quite popular for a time in a number of computers, includ...
https://en.wikipedia.org/wiki/Taligent
Taligent Inc. (a portmanteau of "talent" and "intelligent") was an American software company. Based on the Pink object-oriented operating system conceived by Apple in 1988, Taligent Inc. was incorporated as an Apple/IBM partnership in 1992, and was dissolved into IBM in 1998. In 1988, after launching System 6 and Mult...
https://en.wikipedia.org/wiki/Bytecode
Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, bytecodes are compact numeric codes, constants, and references (normally numeric addresses) that encode the result of compiler parsing and performing...
https://en.wikipedia.org/wiki/Equality%20%28mathematics%29
In mathematics, equality is a relationship between two quantities or, more generally two mathematical expressions, asserting that the quantities have the same value, or that the expressions represent the same mathematical object. The equality between and is written , and pronounced " equals ". The symbol "" is called...
https://en.wikipedia.org/wiki/Super-Poulet%20number
A super-Poulet number is a Poulet number, or pseudoprime to base 2, whose every divisor d divides 2d − 2. For example, 341 is a super-Poulet number: it has positive divisors {1, 11, 31, 341} and we have: (211 - 2) / 11 = 2046 / 11 = 186 (231 - 2) / 31 = 2147483646 / 31 = 69273666 (2341 - 2) / 341 = 131363327986967988...
https://en.wikipedia.org/wiki/ICON%20%28microcomputer%29
The ICON (also the CEMCorp ICON, Burroughs ICON, and Unisys ICON, and nicknamed the bionic beaver) was a networked personal computer built specifically for use in schools, to fill a standard created by the Ontario Ministry of Education. It was based on the Intel 80186 CPU and ran an early version of QNX, a Unix-like op...
https://en.wikipedia.org/wiki/Business%20continuity%20planning
Business continuity may be defined as "the capability of an organization to continue the delivery of products or services at pre-defined acceptable levels following a disruptive incident", and business continuity planning (or business continuity and resiliency planning) is the process of creating systems of prevention ...
https://en.wikipedia.org/wiki/Doubling%20the%20cube
Doubling the cube, also known as the Delian problem, is an ancient geometric problem. Given the edge of a cube, the problem requires the construction of the edge of a second cube whose volume is double that of the first. As with the related problems of squaring the circle and trisecting the angle, doubling the cube is ...
https://en.wikipedia.org/wiki/Angle%20trisection
Angle trisection is a classical problem of straightedge and compass construction of ancient Greek mathematics. It concerns construction of an angle equal to one third of a given arbitrary angle, using only two tools: an unmarked straightedge and a compass. In 1837, Pierre Wantzel proved that the problem, as stated, is...
https://en.wikipedia.org/wiki/Fermat%20number
In mathematics, a Fermat number, named after Pierre de Fermat, the first known to have studied them, is a positive integer of the form where n is a non-negative integer. The first few Fermat numbers are: 3, 5, 17, 257, 65537, 4294967297, 18446744073709551617, ... . If 2k + 1 is prime and , then k itself must be a po...
https://en.wikipedia.org/wiki/Andrey%20Kolmogorov
Andrey Nikolaevich Kolmogorov (, 25 April 1903 – 20 October 1987) was a Soviet mathematician who contributed to the mathematics of probability theory, topology, intuitionistic logic, turbulence, classical mechanics, algorithmic information theory and computational complexity. Biography Early life Andrey Kolmogorov wa...
https://en.wikipedia.org/wiki/System%20analysis
System analysis in the field of electrical engineering characterizes electrical systems and their properties. System analysis can be used to represent almost anything from population growth to audio speakers; electrical engineers often use it because of its direct relevance to many areas of their discipline, most nota...
https://en.wikipedia.org/wiki/Maintenance
The technical meaning of maintenance involves functional checks, servicing, repairing or replacing of necessary devices, equipment, machinery, building infrastructure, and supporting utilities in industrial, business, and residential installations. Over time, this has come to include multiple wordings that describe var...
https://en.wikipedia.org/wiki/Computer%20and%20network%20surveillance
Computer and network surveillance is the monitoring of computer activity and data stored locally on a computer or data being transferred over computer networks such as the Internet. This monitoring is often carried out covertly and may be completed by governments, corporations, criminal organizations, or individuals. I...
https://en.wikipedia.org/wiki/Bartel%20Leendert%20van%20der%20Waerden
Bartel Leendert van der Waerden (; 2 February 1903 – 12 January 1996) was a Dutch mathematician and historian of mathematics. Biography Education and early career Van der Waerden learned advanced mathematics at the University of Amsterdam and the University of Göttingen, from 1919 until 1926. He was much influenced b...
https://en.wikipedia.org/wiki/Existential%20quantification
In predicate logic, an existential quantification is a type of quantifier, a logical constant which is interpreted as "there exists", "there is at least one", or "for some". It is usually denoted by the logical operator symbol ∃, which, when used together with a predicate variable, is called an existential quantifier (...
https://en.wikipedia.org/wiki/Citrulline
The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon. Although named and described by gastroenterologists since the late 19th century, it was first isolated from watermelon in 1914 by Japanese researchers Yotaro Koga and Ryo Odake and further codified by ...
https://en.wikipedia.org/wiki/Circular%20dichroism
Circular dichroism (CD) is dichroism involving circularly polarized light, i.e., the differential absorption of left- and right-handed light. Left-hand circular (LHC) and right-hand circular (RHC) polarized light represent two possible spin angular momentum states for a photon, and so circular dichroism is also referre...
https://en.wikipedia.org/wiki/Magnetic%20circular%20dichroism
Magnetic circular dichroism (MCD) is the differential absorption of left and right circularly polarized (LCP and RCP) light, induced in a sample by a strong magnetic field oriented parallel to the direction of light propagation. MCD measurements can detect transitions which are too weak to be seen in conventional optic...