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Topic Review
Tether (Cryptocurrency)
Tether (often referred to by one of its currency codes, USD₮), is an asset-backed cryptocurrency stablecoin. It was launched by the company Tether Limited Inc. in 2014. Tether Limited is owned by the Hong Kong-based company iFinex Inc., which also owns the Bitfinex cryptocurrency exchange. As of July 2022, Tether Limited has minted the USDT stablecoin on ten protocols and blockchains. Tether is described as a stablecoin because it was originally designed to be valued at USD $1.00, with Tether Limited maintaining USD $1.00 of asset reserves for each USDT issued.
  • 5.9K
  • 16 Nov 2022
Topic Review
Constraints Accounting
Constraints accounting (CA) allow some variations generally accepted accounting principles(GAAP) when reporting financial statements of company and these variations do not violate the GAAP in light of recognised CA. CA contains explicit consideration of the role of constraints in accounting and constraints relate to limitations when providing financial information. The definition of a constraint is a regulation which belongs to prescribed bounds and there are four main types of constraints which are the cost-benefit relationship, materiality, industry practices, and conservatism, and these constraints are also accounting guidelines which border the hierarchy of qualitative information.
  • 5.7K
  • 01 Nov 2022
Topic Review
Bitcoin Core
Bitcoin Core is free and open-source software that serves as a bitcoin node (the set of which form the bitcoin network) and provides a bitcoin wallet which fully verifies payments. It is considered to be bitcoin's reference implementation. Initially, the software was published by Satoshi Nakamoto under the name "Bitcoin", and later renamed to "Bitcoin Core" to distinguish it from the network. For this reason, it is also known as the Satoshi client. The MIT Digital Currency Initiative funds some of the development of Bitcoin Core. The project also maintains the cryptography library libsecp256k1.
  • 5.7K
  • 09 Nov 2022
Topic Review
Concept Learning
Concept learning, also known as category learning, concept attainment, and concept formation, is defined by Bruner, Goodnow, & Austin (1967) as "the search for and listing of attributes that can be used to distinguish exemplars from non exemplars of various categories". More simply put, concepts are the mental categories that help us classify objects, events, or ideas, building on the understanding that each object, event, or idea has a set of common relevant features. Thus, concept learning is a strategy which requires a learner to compare and contrast groups or categories that contain concept-relevant features with groups or categories that do not contain concept-relevant features. In a concept learning task, a human or machine learner is trained to classify objects by being shown a set of example objects along with their class labels. The learner simplifies what has been observed by condensing it in the form of an example. This simplified version of what has been learned is then applied to future examples. Concept learning may be simple or complex because learning takes place over many areas. When a concept is difficult, it is less likely that the learner will be able to simplify, and therefore will be less likely to learn. Colloquially, the task is known as learning from examples. Most theories of concept learning are based on the storage of exemplars and avoid summarization or overt abstraction of any kind.
  • 5.7K
  • 17 Oct 2022
Topic Review
Limit Superior and Limit Inferior
In mathematics, the limit inferior and limit superior of a sequence can be thought of as limiting (i.e., eventual and extreme) bounds on the sequence. They can be thought of in a similar fashion for a function (see limit of a function). For a set, they are the infimum and supremum of the set's limit points, respectively. In general, when there are multiple objects around which a sequence, function, or set accumulates, the inferior and superior limits extract the smallest and largest of them; the type of object and the measure of size is context-dependent, but the notion of extreme limits is invariant. Limit inferior is also called infimum limit, limit infimum, liminf, inferior limit, lower limit, or inner limit; limit superior is also known as supremum limit, limit supremum, limsup, superior limit, upper limit, or outer limit. The limit inferior of a sequence [math]\displaystyle{ x_n }[/math] is denoted by The limit superior of a sequence [math]\displaystyle{ x_n }[/math] is denoted by
  • 5.6K
  • 30 Nov 2022
Topic Review
Cryptography
Cryptography, or cryptology (from Ancient Greek: "hidden, secret"; and γράφειν graphein, "to write", or -λογία -logia, "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security (data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively synonymous with encryption, converting readable information (plaintext) to unintelligible nonsense text (ciphertext), which can only be read by reversing the process (decryption). The sender of an encrypted (coded) message shares the decryption (decoding) technique only with intended recipients to preclude access from adversaries. The cryptography literature often uses the names "Alice" (or "A") for the sender, "Bob" (or "B") for the intended recipient, and "Eve" (or "E") for the eavesdropping adversary. Since the development of rotor cipher machines in World War I and the advent of computers in World War II, cryptography methods have become increasingly complex and their applications more varied. Modern cryptography is heavily based on mathematical theory and computer science practice; cryptographic algorithms are designed around computational hardness assumptions, making such algorithms hard to break in actual practice by any adversary. While it is theoretically possible to break into a well-designed system, it is infeasible in actual practice to do so. Such schemes, if well designed, are therefore termed "computationally secure"; theoretical advances (e.g., improvements in integer factorization algorithms) and faster computing technology require these designs to be continually reevaluated, and if necessary, adapted. Information-theoretically secure schemes that cannot be broken even with unlimited computing power, such as the one-time pad, are much more difficult to use in practice than the best theoretically breakable, but computationally secure, schemes. The growth of cryptographic technology has raised a number of legal issues in the Information Age. Cryptography's potential for use as a tool for espionage and sedition has led many governments to classify it as a weapon and to limit or even prohibit its use and export. In some jurisdictions where the use of cryptography is legal, laws permit investigators to compel the disclosure of encryption keys for documents relevant to an investigation. Cryptography also plays a major role in digital rights management and copyright infringement disputes in regard to digital media.
  • 5.6K
  • 28 Nov 2022
Topic Review
Mortal Kombat
Mortal Kombat is an American media franchise centered on a series of video games, originally developed by Midway Games in 1992. The development of the first game was originally based on an idea that Ed Boon and John Tobias had of making a video game starring Jean-Claude Van Damme, but as that idea fell through, a fantasy-themed fighting game was created instead, nonetheless paying homage to him with nut-cracking movie star character Johnny Cage, whose initials and personal style echo Van Damme's. Mortal Kombat was the first ever fighting game to introduce a secret fighter, reached if the player fulfilled a set of requirements. The original game has spawned many sequels and spin-offs consisting of several action-adventure games, as well as a comic book series and a card game. Film producer Lawrence Kasanoff licensed the rights to the game in the early 1990s and produced the first hit movie ever made from a video game. Lawrence also produced the second movie, animated TV series, live-action TV series films, the first one million platinum-selling album and a live-action tour. Mortal Kombat has become the most successful fighting franchise in the history of video games and one of the highest-grossing media franchises of all time. The series has a reputation for high levels of graphic violence, including, most notably, its Fatalities (finishing moves allowing the player to finish off their defeated opponent). Controversies surrounding Mortal Kombat, in part, led to the creation of the ESRB video game rating system. Early games in this series were also noted for their realistic digitized sprites and an extensive use of palette swapping to create new characters. Following Midway's bankruptcy, the Mortal Kombat development team was acquired by Warner Bros. Entertainment and turned into NetherRealm Studios.
  • 5.6K
  • 19 Oct 2022
Topic Review
Gauss's Lemma (Polynomial)
In algebra, Gauss's lemma, named after Carl Friedrich Gauss, is a statement about polynomials over the integers, or, more generally, over a unique factorization domain (that is, a ring that has a unique factorization property similar to the fundamental theorem of arithmetic). Gauss's lemma underlies all the theory of factorization and greatest common divisors of such polynomials. Gauss's lemma asserts that the product of two primitive polynomials is primitive (a polynomial with integer coefficients is primitive if it has 1 as a greatest common divisor of its coefficients). A corollary of Gauss's lemma, sometimes also called Gauss's lemma, is that a primitive polynomial is irreducible over the integers if and only if it is irreducible over the rational numbers. More generally, a primitive polynomial has the same complete factorization over the integers and over the rational numbers. In the case of coefficients in a unique factorization domain R, "rational numbers" must be replaced by "field of fractions of R". This implies that, if R is either a field, the ring of integers, or a unique factorization domain, then every polynomial ring (in one or several indeterminates) over R is a unique factorization domain. Another consequence is that factorization and greatest common divisor computation of polynomials with integers or rational coefficients may be reduced to similar computations on integers and primitive polynomials. This is systematically used (explicitly or implicitly) in all implemented algorithms (see Polynomial greatest common divisor and Factorization of polynomials). Gauss's lemma, and all its consequences that do not involve the existence of a complete factorization remain true over any GCD domain (an integral domain over which greatest common divisors exist). In particular, a polynomial ring over a GCD domain is also a GCD domain. If one calls primitive a polynomial such that the coefficients generate the unit ideal, Gauss's lemma is true over every commutative ring. However, some care must be taken, when using this definition of primitive, as, over a unique factorization domain that is not a principal ideal domain, there are polynomials that are primitive in the above sense and not primitive in this new sense.
  • 5.5K
  • 28 Nov 2022
Topic Review
Turing Reduction
In computability theory, a Turing reduction from a problem A to a problem B, is a reduction which solves A, assuming the solution to B is already known (Rogers 1967, Soare 1987). It can be understood as an algorithm that could be used to solve A if it had available to it a subroutine for solving B. More formally, a Turing reduction is a function computable by an oracle machine with an oracle for B. Turing reductions can be applied to both decision problems and function problems. If a Turing reduction of A to B exists then every algorithm for B can be used to produce an algorithm for A, by inserting the algorithm for B at each place where the oracle machine computing A queries the oracle for B. However, because the oracle machine may query the oracle a large number of times, the resulting algorithm may require more time asymptotically than either the algorithm for B or the oracle machine computing A, and may require as much space as both together. The first formal definition of relative computability, then called relative reducibility, was given by Alan Turing in 1939 in terms of oracle machines. Later in 1943 and 1952 Stephen Kleene defined an equivalent concept in terms of recursive functions. In 1944 Emil Post used the term "Turing reducibility" to refer to the concept. A polynomial-time Turing reduction is known as a Cook reduction, after Stephen Cook.
  • 5.5K
  • 14 Oct 2022
Topic Review
French Republican Calendar
The French Republican calendar (French: calendrier républicain français), also commonly called the French Revolutionary calendar (calendrier révolutionnaire français), was a calendar created and implemented during the French Revolution , and used by the French government for about 12 years from late 1793 to 1805, and for 18 days by the Paris Commune in 1871. The revolutionary system was designed in part to remove all religious and royalist influences from the calendar, and was part of a larger attempt at decimalisation in France (which also included decimal time of day, decimalisation of currency, and metrication). It was used in government records in France and other areas under French rule, including Belgium, Luxembourg, and parts of the Netherlands, Germany, Switzerland, Malta, and Italy.
  • 5.5K
  • 19 Oct 2022
Topic Review
List of Doom Source Ports
This article is a list of unofficial source ports of the Doom engine, which was originally used in the video game Doom. Most often, the source ports presented here are modifications made by the Doom community, as opposed to the official Doom versions produced by id Software or affiliated companies. The Doom engine's source code was released to the public on December 23, 1997. Although Doom was originally created for MS-DOS, the original source release was for the subsequent Linux version, due to the use of a proprietary sound library in the DOS version. The original purpose of source ports was cross-platform compatibility, but shortly after the release of the Doom source code, programmers were correcting old, unaddressed Doom bugs and deficiencies in their own source ports, and later on introducing their own modifications to enhance game features and alter gameplay. The source code was originally released under a proprietary license that prohibited commercial use and did not require programmers to provide the source code for the modifications they released in executable form, but it was later re-released on October 3, 1999 under the GNU General Public License after requests from the community.
  • 5.5K
  • 06 Feb 2023
Topic Review
Encyclopaedia Metallum
Encyclopaedia Metallum: The Metal Archives (commonly known as Metal Archives per the URL or just MA) is a website which lists bands from various forms of heavy metal music. Encyclopaedia Metallum was described by Matt Sullivan of Nashville Scene as "the Internet's central database for all that is 'tr00' in the metal world." Terrorizer described the site as "a fully-exhaustive list of pretty much every metal band ever, with full discographies, an active forum and an interlinking members list that shows the ever-incestuous beauty of the metal scene". Nevertheless, there are exceptions for bands which fall under disputed genres not accepted by the website. Encyclopaedia Metallum attempts to provide comprehensive information on each band, such as a discography, logos, pictures, lyrics, line-ups, biography, trivia and user-submitted reviews. The site also provides a system for submitting bands to the archives. The website is free of advertisements and is run completely independently.
  • 5.4K
  • 02 Dec 2022
Topic Review
Windows 10 Version History (Version 1607)
The Windows 10 Anniversary Update (also known as version 1607 and codenamed "Redstone 1") is the second major update to Windows 10 and the first in a series of updates under the Redstone codenames. It carries the build number 10.0.14393.
  • 5.4K
  • 20 Oct 2022
Topic Review
Illegal IPTV Technologies
Technologies providing copyright-infringing IPTV content are commonly used as an illegal alternative to legal IPTV subscriptions and services, as they usually have lower monetary costs and can be more convenient for users who follow content from different sources. These infringing IPTV technologies may include websites, software, software add-ons, and physical set-top boxes. Due to the free or low cost of illegal IPTV technologies, illicit IPTV content providers will often resort to intrusive advertising, scams, and the distribution of malware to increase their revenue.
  • 5.4K
  • 20 Oct 2023
Topic Review
Adaptability Quotient
Adaptability Quotient (AQ) is a metric of adaptability used to measure performance in the workplace and assess individual potential. The earliest article published by Stuart Parkin in 2010 gave rise to the term Adaptability Quotient. This has inspired many others to expand and research the area. A recent deep dive into Adaptability Quotient can be found at SingularityU London Adaptability Webinar: "Developing adaptable workforces, a roadmap to recovery", where Ross Thornley, is joined by Jason Slater from UNIDO and Professor Nicolas Deuschel . Additionally Amin Toufani in 2014, shares his insights during his public lecture at Singularity University. he defines AQ as the ability to realize optimal outcomes based on recent or future change. Ross Thornley and Mike Raven's work at AQai is deepening the scientific research of AQ in the workplace, opening up new frontiers of understanding and links across multiple disciplines. Their A.C.E model is widely seen as the most holistic and comprehensive assessment. AQ is defined as, "Measuring the abilities, characteristics, and environmental factors which impact the successful behaviors and actions of people, and organizations to effectively respond to uncertainty, new information, or changed circumstances.” Decoding AQ 2020, Ross Thornley. (As of 2019), there is a growing body of literature surrounding adaptability, and consequent interest in being able to harness, measure, and quantify adaptability in the workplace. Adaptability was identified as the “new competitive advantage” by the Harvard Business Review in 2011. In 2014, The Flux Report (published by Right Management in the UK) revealed that 91% of HR managers thought that: "People will be recruited on their ability to deal with change and uncertainty" as opposed to other skills. Specifically adaptive performance in the research literature means numerous organizational scholars have recognized that traditional models of performance are static and need to be augmented to include "responsiveness to changing job requirements" — labeled adaptive performance (AP; Allworth & Hesketh, 1999, p. 98; Griffin, Neal, & Parker, 2007; Pulakos, Arad, Donovan, & Plamondon, 2000).
  • 5.4K
  • 28 Nov 2022
Topic Review
Google Data Centers
Google Data Centers are the large data center facilities Google uses to provide their services, which combine large drives, computer nodes organized in aisles of racks, internal and external networking, environmental controls (mainly cooling and dehumidification), and operations software (especially as concerns load balancing and fault tolerance). There is no official data on how many servers are in Google data centers, but Gartner estimated in a July 2016 report that Google at the time had 2.5 million servers. This number is changing as the company expands capacity and refreshes its hardware.
  • 5.4K
  • 11 Nov 2022
Topic Review
Long and Short Scale
The long and short scales are two of several naming systems for integer powers of ten which use some of the same terms for different magnitudes. For whole numbers smaller than 1,000,000,000 (109), such as one thousand or one million, the two scales are identical. For larger numbers, starting with 109, the two systems differ. For identical names, the long scale proceeds by powers of one million, whereas the short scale proceeds by powers of one thousand. For example, "one billion" means one thousand millions in the short scale, while it means one million millions in the long scale. The long scale system uses additional terms for the intervening values, typically replacing the word ending -ion with -iard.
  • 5.3K
  • 24 Nov 2022
Topic Review
Delphi (IDE)
Delphi is an integrated development environment (IDE) for rapid application development of desktop, mobile, web, and console software, developed by Embarcadero Technologies. It is also an event-driven language. Delphi's compilers use their own Object Pascal dialect of Pascal and generate native code for Microsoft Windows, macOS (IA-32 only), iOS, Android and Linux (x64 only). Since 2016, there have been new releases of Delphi every six months, with new platforms being added approximately every second release. Delphi includes a code editor, a visual designer, an integrated debugger, a source code control component, and support for third-party plugins. The code editor features Code Insight (code completion), Error Insight (real-time error-checking), and refactoring. The visual forms designer has traditionally used Visual Component Library (VCL) for native Windows development, but the FireMonkey (FMX) platform was later added for cross-platform development. Database support in Delphi is very strong. A Delphi project of a million lines to compile in a few seconds – one benchmark gave 170,000 lines per second. Delphi was originally developed by Borland as a rapid application development tool for Windows as the successor of Turbo Pascal. Delphi added full object-oriented programming to the existing language, and since then the language has grown to support generics and anonymous methods, and native Component Object Model (COM) support. In 2006, Borland’s developer tools section was transferred from Borland to a wholly owned subsidiary known as CodeGear, which was sold to Embarcadero Technologies in 2008. In 2015, Embarcadero was purchased by Idera Software, but the Embarcadero mark was retained for the developer tools division. Delphi and its C++ counterpart, C++Builder, are interoperable. They share many core components, notably the IDE, VCL, and much of the runtime library. In addition, they can be used jointly in a project. For example, C++Builder 6 and later can consume Delphi source code and C++ in one project, while packages compiled with C++Builder can be used from within Delphi. In 2007, the products were released jointly as RAD Studio, a shared host for Delphi and C++Builder, which can be purchased with either or both.
  • 5.2K
  • 02 Nov 2022
Topic Review
Technology Forecasting
Technology forecasting attempts to predict the future characteristics of useful technological machines, procedures or techniques. Researchers create technology forecasts based on past experience and current technological developments. Like other forecasts, technology forecasting can be helpful for both public and private organizations to make smart decisions. By analyzing future opportunities and threats, the forecaster can improve decisions in order to achieve maximum benefits. Today, most countries are experiencing huge social and economic changes, which heavily rely on technology development. By analyzing these changes, government and economic institutions could make plans for future developments. However, not all of historical data can be used for technology forecasting, forecasters also need to adopt advanced technology and quantitative modeling from experts’ researches and conclusions.
  • 5.2K
  • 27 Oct 2022
Topic Review
Trigonometry
Trigonometry (from grc τρίγωνον (trígōnon) 'triangle', and μέτρον (métron) 'measure') is a branch of mathematics that studies relationships between side lengths and angles of triangles. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies. The Greeks focused on the calculation of chords, while mathematicians in India created the earliest-known tables of values for trigonometric ratios (also called trigonometric functions) such as sine. Throughout history, trigonometry has been applied in areas such as geodesy, surveying, celestial mechanics, and navigation. Trigonometry is known for its many identities. These trigonometric identities are commonly used for rewriting trigonometrical expressions with the aim to simplify an expression, to find a more useful form of an expression, or to solve an equation.
  • 5.2K
  • 31 Oct 2022
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