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Topic Review
Ballistic Missile
A ballistic missile follows a ballistic trajectory to deliver one or more warheads on a predetermined target. These weapons are only guided during relatively brief periods of flight—most of their trajectory is unpowered, being governed by gravity and air resistance if in the atmosphere. Shorter range ballistic missiles stay within the Earth's atmosphere, while longer-ranged intercontinental ballistic missiles (ICBMs), are launched on a sub-orbital flight trajectory and spend most of their flight out of the atmosphere. These weapons are in a distinct category from cruise missiles, which are aerodynamically guided in powered flight.
  • 16.6K
  • 05 Nov 2022
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.
  • 16.5K
  • 21 Nov 2022
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.
  • 16.5K
  • 24 Nov 2022
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.
  • 16.5K
  • 16 Jun 2021
Topic Review
DPPH Radical Scavenging Assay
The 1,1-diphenyl-2-picrylhydrazil (DPPH) radical removal is one of the most widely applied and used methods in food and pharmaceutical applications. DPPH method gives a better response for mostly phenolic compounds and then for compounds with limited polarity. In the case of polar and phenolic compounds, adding water to the reaction medium, that is, aqueous methanol, gives better results. When testing low-polarity compounds, ethyl acetate with a radical is suitable. DPPH reaction rates depend on the steric accessibility of the radical site rather than the chemical properties of the tested antioxidant compounds. The rate at which DPPH reacts with antioxidants depends on the varying ratios of mixed single-electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms. The reaction mechanisms of DPPH∙ scavenging and responses are modified by many environmental and experimental factors.
  • 16.5K
  • 08 Sep 2023
Topic Review
Coumarin
Coumarin (2H-1-benzopyran-2-one) is an oxygen containing heterocycle and belongs to the subcategory of lactones.
  • 16.4K
  • 06 Jan 2021
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.
  • 16.4K
  • 13 Oct 2022
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.
  • 16.2K
  • 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).
  • 16.2K
  • 01 Dec 2022
Topic Review
Davidic Line
The Davidic line or House of David (Hebrew: בית דוד‎, romanized: Beit David) refers to the lineage of the Israelite king David through texts in the Hebrew Bible, the New Testament, and through the succeeding centuries. According to the Bible, David, of the Tribe of Judah, was the third king of the United Monarchy of Israel and Judah. He was later succeeded by his son, Solomon. After Solomon's death, the ten northern tribes rejected the Davidic line, refusing to accept Solomon's son, Rehoboam, and instead chose as king Jeroboam and formed the northern Kingdom of Israel. The southern tribes of Judah and Benjamin remained loyal to the House of David, and this kingdom came to be known as the Kingdom of Judah. All subsequent kings of Judah, except Athaliah, are said to be direct descendants of David. The kingdom fell to the Neo-Babylonian Empire in 587/6 BCE. The Hasmoneans, who established their own monarchy in Judea in the 2nd century BCE, were not considered connected to the Davidic line nor to the Tribe of Judah. In Judaism and Christianity, the Davidic Line is the bloodline from which the Hebrew Messiah has a patrilineal descent. In Jewish eschatology, the Messiah is a future Jewish king from the Davidic line, who is expected to rule the Jewish people during the Messianic Age and world to come. The Christian gospels claim that Jesus descends from the Davidic line and is therefore the legitimate Hebrew Messiah. The New Testament books of Matthew and Luke give two different accounts of the genealogy of Jesus that trace back to David.
  • 16.2K
  • 02 Dec 2022
Topic Review
Social Sciences and COVID-19
This entry seeks to provide an answer to the question of what is the relevance of Social Sciences for understanding the multiple implications and challenges posed by the COVID-19 contagion pandemic.
  • 16.2K
  • 16 Nov 2020
Topic Review
Classification of Green Solvents
Green solvents, such as bio-based (derived from renewable sources), water-based (dissolved in water), supercritical fluids (above their critical point), and deep eutectic solvents (formed by mixing two or more components), offer alternatives to conventional organic solvents for bio-oil extraction. These solvents are characterized by being non-toxic, non-volatile, recyclable, and biodegradable.
  • 16.1K
  • 16 Aug 2023
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
  • 16.0K
  • 23 Nov 2022
Topic Review
List of Oxidation States of the Elements
This is a list of known oxidation states of the chemical elements, excluding nonintegral values. The most common states appear in bold. The table is based on that of Greenwood and Earnshaw, with additions noted. Oxidation state 0, which occurs for all elements, is implied by the column with the symbol of the element. The format of the table, which was devised by Dmitri Mendeleev in 1889, shows the periodicity of the oxidation states of the elements.
  • 16.0K
  • 18 Oct 2022
Topic Review
Renewable Energy Supply Chain
The renewable energy supply chain (RESC) is defined as “the transformation of raw energy into usable energy and involves an effective set of management principles from the point of acquisition of energy resources to the point of consumption of usable energy”.
  • 16.0K
  • 16 Feb 2021
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.
  • 16.0K
  • 23 Nov 2022
Topic Review
Fine-tuned Universe
The fine-tuned universe is the proposition that the conditions that allow life in the universe can occur only when certain universal dimensionless physical constants lie within a very narrow range of values, so that if any of several fundamental constants were only slightly different, the universe would be unlikely to be conducive to the establishment and development of matter, astronomical structures, elemental diversity, or life as it is understood. Various possible explanations of ostensible fine-tuning are discussed among philosophers, scientists, theologians, and proponents and detractors of creationism. The fine-tuned universe observation is closely related to, but is not exactly synonymous with, the anthropic principle, which is often used as an explanation of apparent fine-tuning.
  • 16.0K
  • 28 Sep 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.
  • 15.9K
  • 25 Nov 2022
Topic Review
Kangiten
Kangi-ten (Japanese: 歓喜天, "God of Bliss") is a god (deva or ten) in Shingon and Tendai schools of Japanese Buddhism. He is generally considered the Japanese Buddhist form of the Hindu god of wisdom, Ganesha and is sometimes also identified with the bodhisattva Avalokiteshvara. He is also known as Kanki-ten, Shō-ten (聖天, "sacred god" or "noble god"), Daishō-ten ("great noble god"), Daishō Kangi-ten (大聖歓喜天), Tenson (天尊, "venerable god"), Kangi Jizai-ten (歓喜自在天), Shōden-sama, Vinayaka-ten, Binayaka-ten (毘那夜迦天), Ganapatei (誐那缽底) and Zōbi-ten (象鼻天). Kangiten has many aspects and names, associated with Vajrayana (Esoteric Buddhist, Tantric, mantrayana) schools, Shingon being one of them. Although Kangiten is depicted with an elephant's head like Ganesha as a single male deity, his most popular aspect is the Dual(-bodied) Kangiten or the Embracing Kangiten depicted as an elephant-headed male-female human couple standing in an embrace.
  • 15.9K
  • 18 Nov 2022
Topic Review
Social Integration
Social integration is the process during which newcomers or minorities are incorporated into the social structure of the host society. Social integration, together with economic integration and identity integration, are three main dimensions of a newcomers' experiences in the society that is receiving them. A higher extent of social integration contributes to a closer social distance between groups and more consistent values and practices. Bringing together various ethnic groups irrespective of language, caste, creed, etc., without losing one's identity. It gives access to all areas of community life and eliminates segregation. In a broader view, social integration is a dynamic and structured process in which all members participate in dialogue to achieve and maintain peaceful social relations. Social integration does not mean forced assimilation. Social integration is focused on the need to move toward a safe, stable and just society by mending conditions of social conflict, social disintegration, social exclusion, social fragmentation, exclusion and polarization, and by expanding and strengthening conditions of social integration towards peaceful social relations of coexistence, collaboration and cohesion.
  • 15.9K
  • 08 Nov 2022
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