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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Vishvakarman
Vishvakarman (Sanskrit: विश्वकर्मन्, Viśvakarman; lit. "all creating") is the Personification of ultimate reality and deity of the creative power. He is believed to be one of the ancient architect or engineer who created and taught building of ancient monuments, architectures in Bharat, now India. According to the Rigveda It/He is considered to be the architect, divine engineer of universe from before the advent of time.
  • 6.8K
  • 29 Sep 2022
Topic Review
Loss-of-Coolant Accident
A loss-of-coolant accident (LOCA) is a mode of failure for a nuclear reactor; if not managed effectively, the results of a LOCA could result in reactor core damage. Each nuclear plant's emergency core cooling system (ECCS) exists specifically to deal with a LOCA. Nuclear reactors generate heat internally; to remove this heat and convert it into useful electrical power, a coolant system is used. If this coolant flow is reduced, or lost altogether, the nuclear reactor's emergency shutdown system is designed to stop the fission chain reaction. However, due to radioactive decay, the nuclear fuel will continue to generate a significant amount of heat. The decay heat produced by a reactor shutdown from full power is initially equivalent to about 5 to 6% of the thermal rating of the reactor. If all of the independent cooling trains of the ECCS fail to operate as designed, this heat can increase the fuel temperature to the point of damaging the reactor. Under operating conditions, a reactor may passively (that is, in the absence of any control systems) increase or decrease its power output in the event of a LOCA or of voids appearing in its coolant system (by water boiling, for example). This is measured by the coolant void coefficient. Most modern nuclear power plants have a negative void coefficient, indicating that as water turns to steam, power instantly decreases. Two exceptions are the Soviet RBMK and the Canadian CANDU. Boiling water reactors, on the other hand, are designed to have steam voids inside the reactor vessel. Modern reactors are designed to prevent and withstand loss of coolant, regardless of their void coefficient, using various techniques. Some, such as the pebble bed reactor, passively slow down the chain reaction when coolant is lost; others have extensive safety systems to rapidly shut down the chain reaction, and may have extensive passive safety systems (such as a large thermal heat sink around the reactor core, passively-activated backup cooling/condensing systems, or a passively cooled containment structure) that mitigate the risk of further damage.
  • 2.2K
  • 09 Oct 2022
Topic Review
Truevision TGA
Truevision TGA, often referred to as TARGA, is a raster graphics file format created by Truevision Inc. (now part of Avid Technology). It was the native format of TARGA and VISTA boards, which were the first graphic cards for IBM-compatible PCs to support Highcolor/truecolor display. This family of graphic cards was intended for professional computer image synthesis and video editing with PCs; for this reason, usual resolutions of TGA image files match those of the NTSC and PAL video formats. TARGA is an acronym for Truevision Advanced Raster Graphics Adapter; TGA is an initialism for Truevision Graphics Adapter. TGA files commonly have the extension ".tga" on PC DOS/Windows systems and macOS (older Macintosh systems use the "TPIC" type code). The format can store image data with 8, 15, 16, 24, or 32 bits of precision per pixel – the maximum 24 bits of RGB and an extra 8-bit alpha channel. Color data can be color-mapped, or in direct color or truecolor format. Image data may be stored raw, or optionally, a lossless RLE compression similar to PackBits can be employed. This type of compression performs poorly for typical photographic images, but works acceptably well for simpler images, such as icons, cartoons and line drawings.
  • 922
  • 28 Sep 2022
Topic Review
Nations and Intelligence
The relationship between nations and intelligence is a controversial area of study concerning differences between nations in average intelligence test scores, their possible causes, and their correlation with measures of social well-being and economic prosperity. Richard Lynn and Tatu Vanhanen constructed IQ estimates for many countries using literature reviews, student assessment studies and other methodologies to create estimates, which have been widely criticized on theoretical and methodological grounds. Subsequent research by psychologists such as Earl B. Hunt, Jelte Wicherts and Heiner Rindermann has focused on identifying potential national differences in cognitive ability and causal factors, and determining the nature of the relationship of IQ to variables such as GDP, life expectancy, and governance.
  • 10.4K
  • 29 Sep 2022
Topic Review
Morality and Religion
The intersections of morality and religion involve the relationship between religious views and morals. It is common for religions to have value frameworks regarding personal behavior meant to guide adherents in determining between right and wrong. These include the Triple Gems of Jainism, Islam's Sharia, Catholicism's Catechism, Buddhism's Eightfold Path, and Zoroastrianism's "good thoughts, good words, and good deeds" concept, among others. Various sources - such as holy books, oral and written traditions, and religious leaders - may outline and interpret these frameworks. Some religious systems share tenets with secular value-frameworks such as consequentialism, freethought, and utilitarianism. Religion and morality are not synonymous. Though religion may depend on morality, and even develop alongside morality, morality does not necessarily depend upon religion, despite some making "an almost automatic assumption" to this effect. According to The Westminster Dictionary of Christian Ethics, religion and morality "are to be defined differently and have no definitional connections with each other. Conceptually and in principle, morality and a religious value system are two distinct kinds of value systems or action guides." In the views of some, morality and religion can overlap. One definition sees morality as an active process which is, "at the very least, the effort to guide one's conduct by reason, that is, doing what there are the best reasons for doing, while giving equal consideration to the interests of all those affected by what one does." Value judgments can vary greatly between and within the teachings of various religions, past and present. People in some religious traditions, such as Christianity, may derive ideas of right and wrong from the rules and laws set forth in their respective authoritative guides and by their religious leaders. Divine Command Theory equates morality to adherence to authoritative commands in a holy book. Religions such as Buddhism and Hinduism generally draw from some of the broadest canons of religious works. Researchers have shown interest in the relationship between religion and crime and other behavior that does not adhere to contemporary laws and social norms in various countries. Studies conducted in recent years have explored these relationships, but the results have been mixed and sometimes contradictory. The ability of religious faiths to provide useful and consistent value frameworks remains a matter of some debate. Some religious commentators have asserted that one cannot lead a moral life without an absolute lawgiver as a guide. Other observers assert that moral behavior does not rely on religious tenets, and/or that moral guidelines vary over time and space rather than remain absolute, and secular commentators (such as Christopher Hitchens) point to ethical challenges within various religions that conflict with contemporary social norms.
  • 31.7K
  • 28 Sep 2022
Topic Review
Kuroshio Current
The Kuroshio (黒潮), also known as the Black or Japan Current (日本海流, Nihon Kairyū) or the Black Stream, is a north-flowing, warm ocean current on the west side of the North Pacific Ocean. Like the Gulf Stream in the North Atlantic, the Kuroshio is a powerful western boundary current and forms the western limb of the North Pacific Subtropical Gyre.
  • 5.6K
  • 09 Oct 2022
Topic Review
Thermotogae
The Thermotogae are a phylum of the domain Bacteria. The phylum Thermotogae is composed of Gram-negative staining, anaerobic, and mostly thermophilic and hyperthermophilic bacteria.
  • 1.1K
  • 28 Sep 2022
Topic Review
North American A-36 Apache
The North American A-36 Apache (listed in some sources as "Invader", but also called Mustang) was the ground-attack/dive bomber version of the North American P-51 Mustang, from which it could be distinguished by the presence of rectangular, slatted dive brakes above and below the wings. A total of 500 A-36 dive bombers served in the Mediterranean and Southeast Asia theaters during World War II before being withdrawn from operational use in 1944. The A-36 project was a stopgap measure intended to keep North American Aviation (NAA) assembly lines running during the first half of 1942 despite the US having exhausted its funds earmarked for fighter aircraft. When the order came for more P-51s in June 1942, the NAA workforce was thoroughly experienced.
  • 1.3K
  • 28 Sep 2022
Topic Review
Private Equity Secondary Market
In finance, the private equity secondary market (also often called private equity secondaries or secondaries) refers to the buying and selling of pre-existing investor commitments to private equity and other alternative investment funds. Given the absence of established trading markets for these interests, the transfer of interests in private equity funds as well as hedge funds can be more complex and labor-intensive. Sellers of private equity investments sell not only the investments in the fund but also their remaining unfunded commitments to the funds. By its nature, the private equity asset class is illiquid, intended to be a long-term investment for buy-and-hold investors, including "pension funds, endowments and wealthy families selling off their private equity funds before the pools have sold off all their assets". For the vast majority of private equity investments, there is no listed public market; however, there is a robust and maturing secondary market available for sellers of private equity assets. Buyers seek to acquire private equity interests in the secondary market for multiple reasons. For example, the duration of the investment may be much shorter than an investment in the private equity fund initially. Likewise, the buyer may be able to acquire these interests at an attractive price. Finally, the buyer can evaluate the fund's holdings before deciding to purchase an interest in the fund. Conversely, sellers may seek to sell interest for various reasons, including the need to raise capital, the desire to avoid future capital calls, the need to reduce an over-allocation to the asset class or for regulatory reasons. Driven by strong demand for private equity exposure over the past decade, a vast amount of capital has been committed to secondary market funds from investors looking to increase and diversify their private equity exposure.
  • 3.5K
  • 28 Sep 2022
Topic Review
Automated Driving System
An automated driving system is a complex combination of various components that can be defined as systems where perception, decision making, and operation of the automobile are performed by electronics and machinery instead of a human driver, and as introduction of automation into road traffic. This includes handling of the vehicle, destination, as well as awareness of surroundings. While the automated system has control over the vehicle, it allows the human operator to leave all responsibilities to the system.
  • 2.3K
  • 28 Sep 2022
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