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Topic Review
Descartes' Rule of Signs
In mathematics, Descartes' rule of signs, first described by René Descartes in his work La Géométrie, is a technique for getting information on the number of positive real roots of a polynomial. It asserts that the number of positive roots is at most the number of sign changes in the sequence of polynomial's coefficients (omitting the zero coefficients), and that the difference between these two numbers is always even. This implies, in particular, that if the number of sign changes is zero or one, then there are exactly zero or one positive roots, respectively. By a homographic transformation of the variable, one may use Descartes' rule of signs for getting a similar information on the number of roots in any interval. This is the basic idea of Budan's theorem and Budan–Fourier theorem. By repeating the division of an interval into two intervals, one gets eventually a list of disjoints intervals containing together all real roots of the polynomial, and containing each exactly one real root. Descartes rule of signs and homographic transformations of the variable are, nowadays, the basis of the fastest algorithms for computer computation of real roots of polynomials (see Real-root isolation). Descartes himself used the transformation x → –x for using his rule for getting information of the number of negative roots.
  • 816
  • 03 Nov 2022
Topic Review
Java Transaction API
The Java Transaction API (JTA), one of the Java Enterprise Edition (Java EE) APIs, enables distributed transactions to be done across multiple X/Open XA resources in a Java environment. JTA is a specification developed under the Java Community Process as JSR 907. JTA provides for:
  • 814
  • 05 Dec 2022
Topic Review
IoT Critical Infrastructure security
With the ever advancing expansion of the Internet of Things (IoT) into our everyday lives, the number of attack possibilities increases. Furthermore, with the incorporation of the IoT into Critical Infrastructure (CI) hardware and applications, the protection of not only the systems but the citizens themselves has become paramount. To do so, specialists must be able to gain a foothold in the ongoing cyber attack war-zone. By organising the various attacks against their systems, these specialists can not only gain a quick overview of what they might expect but also gain knowledge into the specifications of the attacks based on the categorisation method used. 
  • 812
  • 19 Aug 2021
Topic Review
Exclusion of the Null Hypothesis
In inferential statistics, the null hypothesis (often denoted H0) is a default hypothesis that a quantity to be measured is zero (null). Typically, the quantity to be measured is the difference between two situations, for instance to try to determine if there is a positive proof that an effect has occurred or that samples derive from different batches. The null hypothesis is effectively stating that a quantity (of interest) is larger or equal to zero AND smaller or equal to zero. If either requirement can be positively overturned, the null hypothesis is "excluded from the realm of possibilities". The null hypothesis is generally assumed to remain possibly true. Multiple analyses can be performed to show how the hypothesis should be either: rejected or excluded e.g. having high confidence level, thus demonstrating a statistically significant difference. This is demonstrated by showing that zero is outside of the specified confidence interval of the measurement on either side, typically within the real numbers. Failure to exclude the null hypothesis (with any confidence) does logically NOT confirm or support the (unprovable) null hypothesis. (When you have not proven something is e.g. bigger than x, it does not necessarily mean you have made it plausible that it is smaller or equal than x; alternatively you may just have done a lousy measurement with low accuracy. Confirming the null hypothesis two-sided would amount to positively proving it is bigger or equal than 0 AND to positively proving it is smaller or equal than 0; this is something for which you need infinite accuracy as well as exactly zero effect neither of which normally are realistic. Also measurements will never indicate a non-zero probability of exactly zero difference.) So failure of an exclusion of a null hypothesis amounts to a "don't know" at the specified confidence level; it does not immediately imply null somehow, as the data may already show a (less strong) indication for a non-null. The used confidence level does absolutely certainly not correspond to the likelihood of null at failing to exclude; in fact in this case a high used confidence level expands the still plausible range. A non-null hypothesis can have the following meanings, depending on the author a) a value other than zero is used, b) some margin other than zero is used and c) the "alternative" hypothesis. Testing (excluding or failing to exclude) the null hypothesis provides evidence that there are (or are not) statistically sufficient grounds to believe there is a relationship between two phenomena (e.g., that a potential treatment has a non-zero effect, either way). Testing the null hypothesis is a central task in statistical hypothesis testing in the modern practice of science. There are precise criteria for excluding or not excluding a null hypothesis at a certain confidence level. The confidence level should indicate the likelihood that much more and better data would still be able to exclude the null hypothesis on the same side. The concept of a null hypothesis is used differently in two approaches to statistical inference. In the significance testing approach of Ronald Fisher, a null hypothesis is rejected if the observed data is significantly unlikely to have occurred if the null hypothesis were true. In this case, the null hypothesis is rejected and an alternative hypothesis is accepted in its place. If the data is consistent with the null hypothesis statistically possibly true, then the null hypothesis is not rejected. In neither case is the null hypothesis or its alternative proven; with better or more data, the null may still be rejected. This is analogous to the legal principle of presumption of innocence, in which a suspect or defendant is assumed to be innocent (null is not rejected) until proven guilty (null is rejected) beyond a reasonable doubt (to a statistically significant degree). In the hypothesis testing approach of Jerzy Neyman and Egon Pearson, a null hypothesis is contrasted with an alternative hypothesis, and the two hypotheses are distinguished on the basis of data, with certain error rates. It is used in formulating answers in research. Statistical inference can be done without a null hypothesis, by specifying a statistical model corresponding to each candidate hypothesis, and by using model selection techniques to choose the most appropriate model. (The most common selection techniques are based on either Akaike information criterion or Bayes factor).
  • 812
  • 17 Oct 2022
Topic Review
Kissing Number Problem
In geometry, a kissing number is defined as the number of non-overlapping unit spheres that can be arranged such that they each touch a common unit sphere. For a lattice packing the kissing number is the same for every sphere, but for an arbitrary sphere packing the kissing number may vary from one sphere to another. Other names for kissing number that have been used are Newton number (after the originator of the problem), and contact number. In general, the kissing number problem seeks the maximum possible kissing number for n-dimensional spheres in (n + 1)-dimensional Euclidean space. Ordinary spheres correspond to two-dimensional closed surfaces in three-dimensional space. Finding the kissing number when centers of spheres are confined to a line (the one-dimensional case) or a plane (two-dimensional case) is trivial. Proving a solution to the three-dimensional case, despite being easy to conceptualise and model in the physical world, eluded mathematicians until the mid-20th century. Solutions in higher dimensions are considerably more challenging, and only a handful of cases have been solved exactly. For others investigations have determined upper and lower bounds, but not exact solutions.
  • 812
  • 19 Oct 2022
Topic Review
Enterprise Architect
Sparx Systems Enterprise Architect is a visual modeling and design tool based on the OMG UML. The platform supports: the design and construction of software systems; modeling business processes; and modeling industry based domains. It is used by businesses and organizations to not only model the architecture of their systems, but to process the implementation of these models across the full application development life-cycle.
  • 812
  • 27 Oct 2022
Topic Review
IT Baseline Protection Catalogs
The IT Baseline Protection Catalogs, or IT-Grundschutz-Kataloge, ("IT Baseline Protection Manual" before 2005) are a collection of documents from the Germany Federal Office for Security in Information Technology (BSI) that provide useful information for detecting weaknesses and combating attacks in the information technology (IT) environment (IT cluster). The collection encompasses over 3000 pages, including the introduction and catalogs. It serves as the basis for the IT baseline protection certification of an enterprise.
  • 808
  • 31 Oct 2022
Topic Review
IBM System I
The IBM System i is IBM's previous generation of midrange computer systems for IBM i users, and was subsequently replaced by the IBM Power Systems in April 2008. The platform was first introduced as the AS/400 (Application System/400) on June 21, 1988 and later renamed to the eServer iSeries in 2000. As part of IBM's Systems branding initiative in 2006, it was again renamed to System i. The codename of the AS/400 project was "Silver Lake", named for the lake in downtown Rochester, Minnesota, where development of the system took place. In April 2008, IBM announced its integration with the System p platform. The unified product line is called IBM Power Systems and features support for the IBM i (previously known as i5/OS or OS/400), AIX and GNU/Linux operating systems.
  • 808
  • 24 Nov 2022
Topic Review
IBM Optical Mark and Character Readers
IBM designed, manufactured and sold optical mark and character readers from 1960 until 1984. The IBM 1287 is notable as being the first commercially sold scanner capable of reading handwritten numbers.
  • 807
  • 17 Nov 2022
Topic Review
Alundra 2: A New Legend Begins
Alundra 2: A New Legend Begins (アランドラ2 魔進化の謎, Arandora 2 Ma Shinka no Nazo, Alundra 2: The Mystery of Magic Evolution) is an action role-playing game developed by Matrix Software for the Sony PlayStation. It was published by SCEI in Japan and Activision worldwide. Unlike its predecessor, Alundra, Alundra 2 features a 3D look which opens up a new world of puzzles. Also, despite its title, Alundra 2 is a standalone sequel, and has no ties with the original. It has a whole new story with a different set of characters, including the main character, Flint. Compared to the darker storyline of Alundra, Alundra 2 has a more light-hearted storyline.
  • 802
  • 03 Nov 2022
Topic Review
Jump Super Stars
Jump Super Stars is a 2D crossover fighting game for the Nintendo DS, based on Weekly Shōnen Jump characters. It was developed by Ganbarion and published by Nintendo. The game was released on August 8, 2005, in Japan and accompanied the release of a red Nintendo DS. A sequel, Jump Ultimate Stars, was released in Japan on November 23, 2006.
  • 801
  • 11 Nov 2022
Topic Review
Suzuki TT Superbikes: Real Road Racing Championship
Suzuki TT Superbikes: Real Road Racing, often shortened to simply Suzuki TT Superbikes; also known as TT Superbikes: Real Road Racing in Europe and Japan, is a 2005 motorcycle simulation racing video game developed by Jester Interactive exclusively for the PlayStation 2 gaming console. The game was self–published by Jester in Europe, with Valcon Games and Taito handling publishing in North America and Japan, respectively. In North America, the game is licensed under Suzuki, an automobile manufacturer. The title features over 50 licensed vehicles and is entirely based around the famed Isle of Man TT race, a 60.72 km annual competition held within the Isle of Man. It is the second game based on the race, following the 1995 release of Manx TT Super Bike, though this game was only based on the Manx TT event, which is a small section of the course. The game was available on the PlayStation 3 via the North American PlayStation Store. Suzuki TT Superbikes has since received two sequels.
  • 800
  • 01 Dec 2022
Topic Review
Comparison of Metadata Editors
This article presents a comparison of digital image metadata viewers and metadata editors. A metadata editor is a computer program that allows users to view and edit metadata tags interactively on the computer screen and save them in the graphics file. Usually a metadata viewer is preferred over a metadata editor for viewing tags. A number of metadata editors for various platforms exist. Users choose among them based on factors such as the availability for the user's platform, the feature set and usability of the user interface (UI). The Metadata Working Group (MWG) is a consortium of leading companies in the digital media industry. The MWG publishes technical specifications that describe how to effectively store metadata into digital media files. These royalty-free specifications are made available to software developers, manufacturers and service providers so that they may create products that use metadata in a consistent way, and that allow consumers to better describe, organize and find their media. Where possible, these specifications rely on existing standards, and aim to create a unified and cohesive approach to applying these standards.
  • 796
  • 20 Oct 2022
Topic Review
Periodic Matrix Set
In mathematics, a periodic matrix set is a set of square matrices in which each square matrix is of a different size, and such that each cell within each matrix within a set contains data associated with some type of periodic distribution.
  • 795
  • 13 Oct 2022
Topic Review
Crowns of Power
Crowns of Power, also referred to as CoP, is a 3D fantasy-themed massively multiplayer online role-playing game (MMORPG) released in 2008 by Rampid Interactive, LLC. the game closed in 2010 and was later purchased in 2017 by Conkered Gaming LLC. Crowns of Power takes place in the 3D fantasy world of Arder, a magical world in the center of the universe in which magic prevails. Crowns of Power is mostly known for its unique class system and smaller world populations, creating a unique sense of community unlike any other.
  • 795
  • 19 Oct 2022
Topic Review
CloudBerry Backup
MSP360 Backup (former CloudBerry Backup) is an online backup app developed by MSP360. The software is integrated with 3rd-party cloud storage providers and supports data backup and restore for Windows (desktop and servers), macOS and Linux. Additionally, it offers support for Microsoft SQL Server, Microsoft Exchange, VMware, Hyper-V, Office 365 and G Suite (Google Apps). MSP360 Backup is available in several commercial editions as well as a free offering (MSP360 Backup Desktop Free). MSP360 Managed Backup is a SaaS solution and is designed to help manage backup and recovery across multiple computers or servers.
  • 794
  • 10 Nov 2022
Topic Review
Learning-Assisted Rain Attenuation Prediction Models
Rain attenuation becomes significant to degrade the earth-space or terrestrial radio link’s signal-to-noise ratio (SNR). So, to maintain the desired SNR level, with the help of fade mitigation techniques (FMTs), it needs to control transmitted signals power considering the expected rainfall. However, since the rain event is a random phenomenon, the rain attenuation that may be experienced by a specific link is difficult to estimate. Many empirical, physical, and compound nature-based models exist in the literature to predict the expected rain attenuation. Furthermore, many optimizations and decision-making functions have become simpler since the development of the learning-assisted (LA) technique. In this work, the LA rain attenuation (LARA) model was classified based on input parameters. Besides, for comparative analysis, each of the supported frequency components of LARA models were tabulated, and an accurate contribution of each model was identified. In contrast to all the currently available LARA models, the accuracy and correlation of input-output parameters are presented. Additionally, it summarizes and discusses open research issues and challenges.
  • 792
  • 01 Jun 2021
Topic Review
Ontology-Based Architecture Process of System-of-Systems
System-of-systems (SoS) architecture is crucial in managing complex and interconnected systems. An SoS architecture encompasses not solely its constituent systems (CSs) but also the interconnections and communication processes among them via their interfaces.
  • 792
  • 19 May 2023
Topic Review
Textile-Based Sensors for Biosignal Detection
Biosignals often have to be detected in sports or for medical reasons. Typical biosignals are pulse and ECG (electrocardiogram), breathing, blood pressure, skin temperature, oxygen saturation, bioimpedance, etc. Typically, scientists attempt to measure these biosignals noninvasively, i.e., with electrodes or other sensors, detecting electric signals, measuring optical or chemical information.
  • 789
  • 13 Sep 2021
Topic Review
Google Cast
Google Cast is a proprietary protocol developed by Google for playing Internet-streamed audio/video content on a compatible consumer device. The protocol is used to initiate and control playback of content on digital media players, high-definition televisions, and home audio systems using a mobile device, personal computer, or smart speaker. The protocol was first launched on July 24, 2013, to support Google's first-generation Chromecast player. The Google Cast SDK was released on February 3, 2014, allowing third parties to modify their software to support the protocol. According to Google, over 20,000 Google Cast-ready apps were available as of May 2015. Support for Google Cast has since been integrated into subsequent devices, such as the Nexus Player and other Android TV devices (such as televisions), as well as soundbars, speakers, and later models of the Chromecast. Consumer devices that natively support the protocol are marketed as Chromecast built-in. As of October 2017, over 55 million Chromecasts and Chromecast built-in devices have been sold.
  • 789
  • 19 Oct 2022
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