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Topic Review
Coordination Center for TLD RU
The Coordination Center for TLD RU (the acronym - the Coordination Center for domains .RU/.РФ; the full name - ANO “The Coordination Center for TLD RU”) — is the administrator of Top Level National Domains .RU and .PФ. It serves as the national registry.
  • 853
  • 07 Nov 2022
Topic Review
Gatling
Gatling is an open-source load- and performance-testing framework based on Scala, Akka and Netty. The first stable release was published on January 13, 2012. In 2015, Gatling's founder, Stéphane Landelle, created a company (named "Gatling Corp"), dedicated to the development of the open-source project. According to Gatling Corp's official blog, Gatling was downloaded more than 1,000,000 times (2021). In June 2016, Gatling officially presented Gatling FrontLine, Gatling's Enterprise Version with additional features. The software is designed to be used as a load testing tool for analyzing and measuring the performance of a variety of services, with a focus on web applications. Gatling was mentioned twice in ThoughtWorks Technology Radar, in 2013 and 2014, "as a tool worth trying", with an emphasis on "the interesting premise of treating your performance tests as production code". The latest stable release is Gatling 3.8.0, published on July 06, 2022.
  • 853
  • 08 Nov 2022
Topic Review
Incompatible Timesharing System
Incompatible Timesharing System (ITS) is a time-sharing operating system developed principally by the MIT Artificial Intelligence Laboratory, with help from Project MAC. The name is the jocular complement of the MIT Compatible Time-Sharing System (CTSS). ITS, and the software developed on it, were technically and culturally influential far beyond their core user community. Remote "guest" or "tourist" access was easily available via the early ARPAnet, allowing many interested parties to informally try out features of the operating system and application programs. The wide-open ITS philosophy and collaborative online community were a major influence on the hacker culture, as described in Steven Levy's book Hackers, and were the direct forerunners of the free and open-source software, open-design, and Wiki movements.
  • 850
  • 04 Nov 2022
Topic Review
Health Service Executive Cyberattack
On 14 May 2021, the Health Service Executive (HSE) of the Republic of Ireland suffered a major ransomware cyberattack that caused all of its IT systems nationwide to be shut down. It was the most significant cybercrime attack on an Irish state agency. Bloomberg News reported that the attackers used the Conti ransomware. The group responsible was identified as a criminal gang known as Wizard Spider, believed to be operating from Russia. The same group is believed to have attacked the Department of Health with a similar cyberattack. On 19 May, the Financial Times reviewed private data for twelve individuals which had appeared online as a result of the breach, with admission records and test results present in one case.
  • 847
  • 27 Oct 2022
Topic Review
Differentiable Vector-Valued Functions from Euclidean Space
In the mathematical discipline of functional analysis, a differentiable vector-valued function from Euclidean space is a differentiable function valued in a topological vector space (TVS) whose domains is a subset of some finite-dimensional Euclidean space. It is possible to generalize the notion of derivative to functions whose domain and codomain are subsets of arbitrary topological vector spaces (TVSs) in multiple ways. But when the domain of a TVS-valued function is a subset of a finite-dimensional Euclidean space then many of these notions become logically equivalent resulting in a much more limited number of generalizations of the derivative and additionally, differentiability is also more well-behaved compared to the general case. This article presents the theory of [math]\displaystyle{ k }[/math]-times continuously differentiable functions on an open subset [math]\displaystyle{ \Omega }[/math] of Euclidean space [math]\displaystyle{ \R^n }[/math] ([math]\displaystyle{ 1 \leq n \lt \infty }[/math]), which is an important special case of differentiation between arbitrary TVSs. This importance stems partially from the fact that every finite-dimensional vector subspace of a Hausdorff topological vector space is TVS isomorphic to Euclidean space [math]\displaystyle{ \R^n }[/math] so that, for example, this special case can be applied to any function whose domain is an arbitrary Hausdorff TVS by restricting it to finite-dimensional vector subspaces. All vector spaces will be assumed to be over the field [math]\displaystyle{ \mathbb{F}, }[/math] where [math]\displaystyle{ \mathbb{F} }[/math] is either the real numbers [math]\displaystyle{ \R }[/math] or the complex numbers [math]\displaystyle{ \Complex. }[/math]
  • 845
  • 07 Nov 2022
Topic Review
Computer (Job Description)
The term "computer", in use from the early 17th century (the first known written reference dates from 1613), meant "one who computes": a person performing mathematical calculations, before electronic computers became commercially available. Alan Turing described the "human computer" as someone who is "supposed to be following fixed rules; he has no authority to deviate from them in any detail." Teams of people, often women from the late nineteenth century onwards, were used to undertake long and often tedious calculations; the work was divided so that this could be done in parallel. The same calculations were frequently performed independently by separate teams to check the correctness of the results. Since the end of the 20th century, the term "human computer" has also been applied to individuals with prodigious powers of mental arithmetic, also known as mental calculators.
  • 844
  • 01 Nov 2022
Topic Review
Hypercycle
In chemistry, a hypercycle is an abstract model of organization of self-replicating molecules connected in a cyclic, autocatalytic manner. It was introduced in an ordinary differential equation (ODE) form by the Nobel Prize winner Manfred Eigen in 1971 and subsequently further extended in collaboration with Peter Schuster. It was proposed as a solution to the error threshold problem encountered during modelling of replicative molecules that hypothetically existed on the primordial Earth (see: abiogenesis). As such, it explained how life on Earth could have begun using only relatively short genetic sequences, which in theory were too short to store all essential information. The hypercycle is a special case of the replicator equation. The most important properties of hypercycles are autocatalytic growth competition between cycles, once-for-ever selective behaviour, utilization of small selective advantage, rapid evolvability, increased information capacity, and selection against parasitic branches.
  • 843
  • 19 Oct 2022
Topic Review
GIS Live DVD
GIS Live DVD is a type of the thematic Live CD containing GIS/RS applications and related tutorials, and sample data sets. The general sense of a GIS Live DVD is to demonstrate the power of FLOSS GIS and encourage users to start on FLOSS GIS. However, a disc can be used for GIS data processing and training, too. A disc usually includes some selected Linux-based or Wine-enabled Windows applications for GIS and Remote Sensing use. Using this disc the end users can execute GIS functions to get experience in free and open source software solutions or solve some simple business operations. The set-up and the operating behaviour of the applications can also be studied prior to building real FLOSS GIS-based systems. Recently a LiveDVD image is stored and booted from USB (Live USB).
  • 843
  • 01 Dec 2022
Topic Review
National Electronic Library for Health
The National electronic Library for Health (NeLH) was a digital library service provided by the NHS for healthcare professionals and the public between 1998 and 2006. It briefly became the National Library for Health and elements of it continue to this day as NHS Evidence, managed by the National Institute for Health and Care Excellence, and a range of services provided by Health Education England's Library and Knowledge Service Leads.
  • 842
  • 10 Oct 2022
Topic Review
MiniD
The MiniD (has been renamed Croc) programming language is a small, lightweight, extension language in the vein of Lua or Squirrel, but designed to be used mainly with the D programming language. It supports both object-oriented and imperative programming paradigms, as well as some simple functional aspects. Distributed under the licence of zlib/libpng, MiniD is free software.
  • 841
  • 29 Nov 2022
Topic Review
Ten Rays Model
The ten-ray model is a model applied to the transmissions in the urban area, to generate a model of ten rays typically four rays more are added to the six rays model, these are ([math]\displaystyle{ R3 }[/math] and [math]\displaystyle{ R4 }[/math] bouncing on both sides of the wall); This incorporate paths from one to three reflections: specifically, there is the LOS (Line of sight), GR (ground reflected), SW (single-wall reflected), DW (double-wall reflected), TW (triple-wall reflected), WG (wall-ground reflected) and GW (ground-wall reflected paths). Where each one of the paths bounces on both sides of the wall. Experimentally, it has been demonstrated that the ten ray model simulates or can represent the propagation of signals through a dielectric canyon, in it which the rays that travel from a transmitter point to a receiver point bounce many times. As example for this model it is assume: a rectilinear free space with two walls, one upper and the other lower, from which two vertical bases are positioned at their ends, these are the transmitting and receiving antennas that it’s locate in such a way that their heights don’t surpass the limits of the top wall; Achieved this the structure acts as free space for its functioning similar to that of a dielectric canyon of signals propagation, since the rays transmitted from the transmitting antenna will collide each side of the upper and lower walls infinity of times (for this example up to 3 reflections) until reaching the receiving antenna. During the course of the rays for each reflection they suffer, part of the energy of the signal is dissipated in each reflection, normally after the third reflection of said ray its resulting component which is a retro-reflected ray is insignificant with a negligible energy.
  • 839
  • 01 Dec 2022
Topic Review
Ex-tangential Quadrilateral
In Euclidean geometry, an ex-tangential quadrilateral is a convex quadrilateral where the extensions of all four sides are tangent to a circle outside the quadrilateral. It has also been called an exscriptible quadrilateral. The circle is called its excircle, its radius the exradius and its center the excenter (E in the figure). The excenter lies at the intersection of six angle bisectors. These are the internal angle bisectors at two opposite vertex angles, the external angle bisectors (supplementary angle bisectors) at the other two vertex angles, and the external angle bisectors at the angles formed where the extensions of opposite sides intersect (see the figure to the right, where four of these six are dotted line segments). The ex-tangential quadrilateral is closely related to the tangential quadrilateral (where the four sides are tangent to a circle). Another name for an excircle is an escribed circle, but that name has also been used for a circle tangent to one side of a convex quadrilateral and the extensions of the adjacent two sides. In that context all convex quadrilaterals have four escribed circles, but they can at most have one excircle.
  • 838
  • 08 Oct 2022
Topic Review
LPWAN Key Exchange
The Internet of Things (IoT) is one of the fastest emerging technologies in the industry. It includes diverse applications with different requirements to provide services to users. Secure, low-powered, and long-range transmissions are some of the most vital requirements in developing IoT applications. IoT uses several communication technologies to fulfill transmission requirements. However, Low Powered Wide Area Networks (LPWAN) transmission standards have been gaining attention because of their exceptional low-powered and long-distance transmission capabilities. The features of LPWAN transmission standards make them a perfect candidate for IoT applications. However, the current LPWAN standards lack state-of-the-art security mechanisms because of the limitations of the IoT devices in energy and computational capacity. Most of the LPWAN standards, such as Sigfox, NB-IoT, and Weightless, use static keys for node authentication and encryption. LoRaWAN is the only LPWAN technology providing session key mechanisms for better security. However, the session key mechanism is vulnerable to replay attacks.
  • 837
  • 22 Jul 2022
Topic Review
DNIX
DNIX (original spelling: D-Nix) is a discontinued Unix-like real-time operating system from the Swedish company Dataindustrier AB (DIAB). A version named ABCenix was developed for the ABC 1600 computer from Luxor. Daisy Systems also had a system named Daisy DNIX on some of their computer-aided design (CAD) workstations. It was unrelated to DIAB's product.
  • 837
  • 01 Nov 2022
Topic Review
Livescribe
The Livescribe paper-based computing platform consists of a digital pen, digital paper, software applications, and developer tools. Central to the Livescribe platform is the smartpen, a ballpoint pen with an embedded computer and digital audio recorder. When used with Anoto digital paper, it records what it writes for later uploading to a computer, and synchronizes those notes with any audio it has recorded. This allows users to replay portions of a recording by tapping on the notes they were taking at the time the recording was made. It is also possible to select which portion of a recording to replay by clicking on the relevant portion of a page on-screen, once it has been synced to the Livescribe Desktop software. Jim Marggraff, inventor of the LeapFrog FLY Pentop computer and creator of the LeapPad Learning System, left Leapfrog in 2005 to form Livescribe. In November 2015, Livescribe announced its acquisition by Anoto for $15m.
  • 832
  • 17 Oct 2022
Topic Review
X Display Manager (Program Type)
In the X Window System, an X display manager is a graphical login manager which starts a session on an X server from the same or another computer. A display manager presents the user with a login screen. A session starts when a user successfully enters a valid combination of username and password. When the display manager runs on the user's computer, it starts the X server before presenting the user the login screen, optionally repeating when the user logs out. In this condition, the DM realizes in the X Window System the functionality of getty and login on character-mode terminals. When the display manager runs on a remote computer, it acts like a telnet server, requesting username and password and starting a remote session. X11 Release 3 introduced display managers in October 1988 with the aim of supporting the standalone X terminals, just coming onto the market. Various display managers continue in routine use to provide a graphical login prompt on standalone computer workstations running X. X11R4 introduced the X Display Manager Control Protocol (XDMCP) in December 1989 to fix problems in the X11R3 implementation.
  • 831
  • 29 Sep 2022
Topic Review
Cybersecurity in Smart Cities
Smart technologies, such as the Internet of Things (IoT), cloud computing, and artificial intelligence (AI), are being adopted in cities and transforming them into smart cities. In smart cities, various network technologies, such as the Internet and IoT, are combined to exchange real-time information, making the everyday lives of their residents more convenient.  Cybersecurity for smart cities includes a combination of technologies that have emerged to address the highly complex challenges of insecure devices and networks, which can lead to unbounded attacks. 
  • 830
  • 17 Apr 2023
Topic Review
Linear Difference Equation
In mathematics and in particular dynamical systems, a linear difference equation:ch. 17:ch. 10 or linear recurrence relation sets equal to 0 a polynomial that is linear in the various iterates of a variable—that is, in the values of the elements of a sequence. The polynomial's linearity means that each of its terms has degree 0 or 1. Usually the context is the evolution of some variable over time, with the current time period or discrete moment in time denoted as t, one period earlier denoted as t − 1, one period later as t + 1, etc. An nth order linear difference equation is one that can be written in terms of parameters a1, …, an and b as or equivalently as The equation is called homogeneous if b = 0 and nonhomogeneous if b ≠ 0. Since the longest time lag between iterates appearing in the equation is n, this is an nth order equation, where n could be any positive integer. When the longest lag is specified numerically so n does not appear notationally as the longest time lag, n is occasionally used instead of t to index iterates. In the most general case the coefficients ai and b could themselves be functions of t; however, this article treats the most common case, that of constant coefficients. If the coefficients ai are polynomials in t the equation is called a linear recurrence equation with polynomial coefficients. The solution of such an equation is a function of t, and not of any iterate values, giving the value of the iterate at any time. To find the solution it is necessary to know the specific values (known as initial conditions) of n of the iterates, and normally these are the n iterates that are oldest. The equation or its variable is said to be stable if from any set of initial conditions the variable's limit as time goes to infinity exists; this limit is called the steady state. Difference equations are used in a variety of contexts, such as in economics to model the evolution through time of variables such as gross domestic product, the inflation rate, the exchange rate, etc. They are used in modeling such time series because values of these variables are only measured at discrete intervals. In econometric applications, linear difference equations are modeled with stochastic terms in the form of autoregressive (AR) models and in models such as vector autoregression (VAR) and autoregressive moving average (ARMA) models that combine AR with other features.
  • 828
  • 25 Nov 2022
Topic Review
Albert Odyssey (Super Famicom Game)
Albert Odyssey (アルバートオデッセイ, Arubaato Odessei) is a tactical role-playing video game developed and published by Sunsoft and released for the Super Nintendo Entertainment System in Japan in March 1993. The game features strategy-based combat in addition to traditional role-playing game elements in two-dimensional environments. It is the first game in the Albert Odyssey series, and was followed by two sequels, Albert Odyssey 2: Jashin no Taidou in 1994, and Albert Odyssey in 1996. On June 12, 1996, Albert Odyssey was made available as a full game download on the Satellaview add-on as BS Albert Odyssey (BSアルバートオデッセイ, BS Arubaato Odessei), and the original Albert Odyssey was re-released for Satellaview in March 1998. Players assume the role of Albert, the young heroic swordsman who lives in a fantasy world filled with monsters and mythical creatures. While much of the world remains in relative peace following a great war many years before, a military faction led by the dark magician Globus has emerged to conquer the newly pacified nations and expand their empire. With the help of Albert's friends as well as hired mercenaries, the player must travel the world and eventually confront Golbus and his forces to prevent another large-scale conflict.
  • 825
  • 10 Oct 2022
Topic Review
Applications of Artificial Intelligence to Legal Informatics
Artificial intelligence and law (AI and law) is a subfield of artificial intelligence (AI) mainly concerned with applications of AI to legal informatics problems and original research on those problems. It is also concerned to contribute in the other direction: to export tools and techniques developed in the context of legal problems to AI in general. For example, theories of legal decision making, especially models of argumentation, have contributed to knowledge representation and reasoning; models of social organization based on norms have contributed to multi-agent systems; reasoning with legal cases has contributed to case-based reasoning; and the need to store and retrieve large amounts of textual data has resulted in contributions to conceptual information retrieval and intelligent databases.
  • 825
  • 31 Oct 2022
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