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Topic Review
Boarhounds
Boarhounds are hunting dogs bred for hunting wild boar. The most commonly used for this purpose are hounds, dachshunds or terriers, but pointers, spitz or retrievers can also be used. The dog should be courageous, persistent, passionate, disciplined, sharp and obedient. Hunting in this group of dogs can be carried out individually and for such breeds are used small and collective breeds as well as medium and large breeds of dogs.
  • 17.0K
  • 16 Jun 2021
Topic Review
List of Anatomy Mnemonics
This is a list of human anatomy mnemonics, categorized and alphabetized. For mnemonics in other medical specialties, see this list of medical mnemonics.
  • 16.9K
  • 24 Nov 2022
Topic Review
Impact of Nanotechnology
The impact of nanotechnology extends from its medical, ethical, mental, legal and environmental applications, to fields such as engineering, biology, chemistry, computing, materials science, and communications. Major benefits of nanotechnology include improved manufacturing methods, water purification systems, energy systems, physical enhancement, nanomedicine, better food production methods, nutrition and large-scale infrastructure auto-fabrication. Nanotechnology's reduced size may allow for automation of tasks which were previously inaccessible due to physical restrictions, which in turn may reduce labor, land, or maintenance requirements placed on humans. Potential risks include environmental, health, and safety issues; transitional effects such as displacement of traditional industries as the products of nanotechnology become dominant, which are of concern to privacy rights advocates. These may be particularly important if potential negative effects of nanoparticles are overlooked. Whether nanotechnology merits special government regulation is a controversial issue. Regulatory bodies such as the United States Environmental Protection Agency and the Health and Consumer Protection Directorate of the European Commission have started dealing with the potential risks of nanoparticles. The organic food sector has been the first to act with the regulated exclusion of engineered nanoparticles from certified organic produce, firstly in Australia and the UK, and more recently in Canada , as well as for all food certified to Demeter International standards
  • 16.9K
  • 18 Oct 2022
Topic Review
Relative Hour (Jewish Law)
Relative hour (Hebrew singular: shaʿah zǝmanit / שעה זמנית; plural: shaʿot - zǝmaniyot / שעות זמניות), sometimes called halachic hour, seasonal hour and variable hour, is a term used in rabbinic Jewish law that assigns 12 hours to each day and 12 hours to each night, all throughout the year. A relative hour has no fixed radical, but changes with the length of each day - depending on summer (when the days are long and the nights are short), and on winter (when the days are short and the nights are long). Even so, in all seasons a day is always divided into 12 hours, and a night is always divided into 12 hours, which inevitably makes for a longer hour or a shorter hour. All of the hours mentioned by the Sages in either the Mishnah or Talmud, or in other rabbinic writings, refer strictly to relative hours. Another feature of this ancient practice is that, unlike the standard modern 12-hour clock that assigns 12 o'clock pm for noon time, in the ancient Jewish tradition noon time was always the sixth hour of the day, whereas the first hour began with the break of dawn, by most exponents of Jewish law, and with sunrise by the Vilna Gaon and Rabbi Hai Gaon. 12:o'clock am (midnight) was also the sixth hour of the night, whereas the first hour of the night began when the first three stars appeared in the night sky.
  • 16.9K
  • 19 Oct 2022
Topic Review
The Evolution of Computers
This research explores the evolution of computing from the earliest mechanical devices to the latest cutting-edge technologies. It covers the development of electronic computers in the 1940s and their impact on military, scientific, and business operations. Mainframe computers of the 1950s and 1960s are discussed, including their role in business computing and financial innovation. The personal computer revolution of the 1970s and the rise of mobile computing in the 1980s and 2000s are also examined. The research concludes with a look at the latest developments in computing, including quantum computing and artificial intelligence, and the potential impact of these technologies on society. It emphasizes the importance of working together to address the challenges of emerging technologies and ensuring their ethical and equitable use.
  • 16.9K
  • 22 May 2023
Topic Review
Power Electronic Switches
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less ‘forgotten’ power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch.
  • 16.9K
  • 29 Dec 2020
Topic Review
Fifth Generation Computer
The Fifth Generation Computer Systems (FGCS) was an initiative by Japan's Ministry of International Trade and Industry (MITI), begun in 1982, to create computers using massively parallel computing and logic programming. It was to be the result of a government/industry research project in Japan during the 1980s. It aimed to create an "epoch-making computer" with supercomputer-like performance and to provide a platform for future developments in artificial intelligence. There was also an unrelated Russian project also named as a fifth-generation computer (see Kronos (computer)). Ehud Shapiro, in his "Trip Report" paper (which focused the FGCS project on concurrent logic programming as the software foundation for the project), captured the rationale and motivations driving this project: The term "fifth generation" was intended to convey the system as being advanced. In the history of computing hardware, computers using vacuum tubes were called the first generation; transistors and diodes, the second; integrated circuits, the third; and those using microprocessors, the fourth. Whereas previous computer generations had focused on increasing the number of logic elements in a single CPU, the fifth generation, it was widely believed at the time, would instead turn to massive numbers of CPUs for added performance. The project was to create the computer over a ten-year period, after which it was considered ended and investment in a new "sixth generation" project would begin. Opinions about its outcome are divided: either it was a failure, or it was ahead of its time.
  • 16.9K
  • 21 Oct 2022
Topic Review
Classification of Uncrewed Aerial Vehicles
Uncrewed aerial vehicles (UAVs), also known as drones, are ubiquitous and their use cases extend today from governmental applications to civil applications such as the agricultural, medical, and transport sectors, etc. In accordance with the requirements in terms of demand, it is possible to carry out various missions involving several types of UAVs as well as various onboard sensors. 
  • 16.9K
  • 04 May 2023
Topic Review
Overhead Camshaft
Overhead camshaft, commonly abbreviated to OHC, is a valvetrain configuration which places the camshaft of an internal combustion engine of the reciprocating type within the cylinder heads ("above" the pistons and combustion chambers) and drives the valves or lifters in a more direct manner compared with overhead valves (OHV) and pushrods.
  • 16.7K
  • 21 Nov 2022
Topic Review
Cost of Electricity by Source
The distinct methods of electricity generation can incur significantly different costs and these costs can occur at significantly different times relative to when the power is used. Also, calculations of these costs can be made at the point of connection to a load or to the electricity grid (ie they may or may not include the transmission costs). The costs include the initial capital, and the costs of continuous operation, fuel, and maintenance as well as the costs of de-commissioning and remediating any environmental damage. For comparing different methods, it is useful to compare costs per unit of energy which is typically given per kilowatt-hour or megawatt-hour. This type of calculation assists policymakers, researchers and others to guide discussions and decision-making but is usually complicated by the need to take account of differences in timing by means of a discount rate.
  • 16.6K
  • 13 Oct 2022
Topic Review
Coumarin
Coumarin (2H-1-benzopyran-2-one) is an oxygen containing heterocycle and belongs to the subcategory of lactones.
  • 16.6K
  • 06 Jan 2021
Topic Review
Traditional Najd Architecture
The research focuses on the architectural typologies and the architectural elements of the cultural heritage in the Najd region. Najd is the great central plateau of Saudi Arabia, of which Riyadh is the most important city and the capital. The contribution leads the architects to rethink the constructive and aesthetic approach in designing and constructing new architectures without forgetting the culture and historical context of reference. The expressiveness of architectural language in terms of the formal and aesthetic approach is a feature that should not be secondary in contemporary buildings. The surface, texture, form, representation, and expression should prevail over aesthetic purposes in architecture.
  • 16.5K
  • 19 Jun 2023
Topic Review
Microsoft Visual C
Microsoft Visual C++ (often abbreviated to MSVC) is an integrated development environment (IDE) product from Microsoft for the C, C++, and C++/CLI programming languages. MSVC is proprietary software; it was originally a standalone product but later became a part of Visual Studio and made available in both trialware and freeware forms. It features tools for developing and debugging C++ code, especially code written for the Windows API, DirectX and .NET. Many applications require redistributable Visual C++ runtime library packages to function correctly. These packages are often installed independently of applications, allowing multiple applications to make use of the package while only having to install it once. These Visual C++ redistributable and runtime packages are mostly installed for standard libraries that many applications use.
  • 16.4K
  • 11 Oct 2022
Topic Review
Sigma-Algebra
In mathematical analysis and in probability theory, a σ-algebra (also σ-field) on a set X is a collection Σ of subsets of X that includes the empty subset, is closed under complement, and is closed under countable unions and countable intersections. The pair (X, Σ) is called a measurable space or Borel space. A σ-algebra is a type of algebra of sets. An algebra of sets needs only to be closed under the union or intersection of finitely many subsets, which is a weaker condition. The main use of σ-algebras is in the definition of measures; specifically, the collection of those subsets for which a given measure is defined is necessarily a σ-algebra. This concept is important in mathematical analysis as the foundation for Lebesgue integration, and in probability theory, where it is interpreted as the collection of events which can be assigned probabilities. Also, in probability, σ-algebras are pivotal in the definition of conditional expectation. In statistics, (sub) σ-algebras are needed for the formal mathematical definition of a sufficient statistic, particularly when the statistic is a function or a random process and the notion of conditional density is not applicable. If X = {a, b, c, d}, one possible σ-algebra on X is Σ = { ∅, {a, b}, {c, d}, {a, b, c, d} }, where ∅ is the empty set. In general, a finite algebra is always a σ-algebra. If {A1, A2, A3, …} is a countable partition of X then the collection of all unions of sets in the partition (including the empty set) is a σ-algebra. A more useful example is the set of subsets of the real line formed by starting with all open intervals and adding in all countable unions, countable intersections, and relative complements and continuing this process (by transfinite iteration through all countable ordinals) until the relevant closure properties are achieved (a construction known as the Borel hierarchy).
  • 16.3K
  • 01 Dec 2022
Topic Review
Decimation (Signal Processing)
In digital signal processing, decimation is the process of reducing the sampling rate of a signal.  The term downsampling usually refers to one step of the process, but sometimes the terms are used interchangeably.  Complementary to upsampling, which increases sampling rate, decimation is a specific case of sample rate conversion in a multi-rate digital signal processing system. A system component that performs decimation is called a decimator. When decimation is performed on a sequence of samples of a signal or other continuous function, it produces an approximation of the sequence that would have been obtained by sampling the signal at a lower rate (or density, as in the case of a photograph). The decimation factor is usually an integer or a rational fraction greater than one. This factor multiplies the sampling interval or, equivalently, divides the sampling rate. For example, if compact disc audio at 44,100 samples/second is decimated by a factor of 5/4, the resulting sample rate is 35,280.
  • 16.3K
  • 23 Nov 2022
Topic Review
Ginger and Iron Deficiency Anaemia
Ginger (Zingiber officinale) is rich in natural polyphenols and may potentially complement oral iron therapy in treating and preventing iron deficiency anaemia (IDA). Ginger possesses several health-promoting properties and has been traditionally used in East Asia to ease fatigue and weaknesses. Contemporarily, ginger is considered a functional food that can confer health benefits beyond its nutritional values for preventing, managing, or treating disease. As a rich source of natural polyphenols, ginger may potentially complement oral iron therapy in treating IDA and be a supportive dietary strategy for preventing IDA. 
  • 16.3K
  • 31 Oct 2022
Topic Review
Burden of Proof
The burden of proof (Latin: onus probandi, shortened from Onus probandi incumbit ei qui dicit, non ei qui negat) is the obligation on a party in a dispute to provide sufficient warrant for its position.
  • 16.2K
  • 25 Nov 2022
Topic Review Peer Reviewed
Revenue Sharing in Professional Sports Leagues
This entry provides a review of economic models of professional sports leagues with and without revenue sharing. These include models that assume profit-maximizing and win-maximizing (sportsmen) club owners. Both approaches predict that revenue sharing will reduce the demand for player talent, depress player salaries, and transfer revenue from large-market to small-market clubs, but they differ on league parity effects. Empirical work has been sparse due to financial data limitations and has not yielded definitive results on the parity issue. Despite the growing awareness of sports economics in the sports industry, the lack of consensus from theoretical models has resulted in sports leagues searching for an optimal revenue sharing policy. The difficulty in providing consistent policy prescriptions in models that incorporate revenue sharing, salary caps, and other league policies has made economic modeling of sports leagues very difficult and complex. While revenue sharing remains an interesting theoretical modeling issue, it has not bridged the gap to real-world league policies.
  • 16.2K
  • 30 Jul 2024
Topic Review
Vision in Fishes
Vision is an important sensory system for most species of fish. Fish eyes are similar to the eyes of terrestrial vertebrates like birds and mammals, but have a more spherical lens. Birds and mammals (including humans) normally adjust focus by changing the shape of their lens, but fish normally adjust focus by moving the lens closer to or further from the retina. Fish retinas generally have both rod cells and cone cells (for scotopic and photopic vision), and most species have colour vision. Some fish can see ultraviolet and some are sensitive to polarized light. Among jawless fishes, the lamprey has well-developed eyes, while the hagfish has only primitive eyespots. The ancestors of modern hagfish, thought to be the protovertebrate were evidently pushed to very deep, dark waters, where they were less vulnerable to sighted predators, and where it is advantageous to have a convex eye-spot, which gathers more light than a flat or concave one. Fish vision shows evolutionary adaptation to their visual environment, for example deep sea fish have eyes suited to the dark environment.
  • 16.2K
  • 10 Nov 2022
Topic Review
Jet Engine Thrust
The familiar explanation for jet thrust is a "black box" description which only looks at what goes into the jet engine, air and fuel, and what comes out, exhaust gas and an unbalanced force. This force, called thrust, is the sum of the momentum difference between entry and exit and any unbalanced pressure force between entry and exit, as explained in "Thrust calculation". As an example, an early turbojet, the Bristol Olympus Mk. 101, had a momentum thrust of 9300 lb. and a pressure thrust of 1800 lb. giving a total of 11,100 lb. Looking inside the "black box" shows that the thrust results from all the unbalanced momentum and pressure forces created within the engine itself. These forces, some forwards and some rearwards, are across all the internal parts, both stationary and rotating, such as ducts, compressors, etc., which are in the primary gas flow which flows through the engine from front to rear. The algebraic sum of all these forces is delivered to the airframe for propulsion. "Flight" gives examples of these internal forces for two early jet engines, the Rolls-Royce Avon Ra.14 and the de Havilland Goblin
  • 16.2K
  • 23 Nov 2022
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