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Topic Review
High Frequency Active Auroral Research Program
The High Frequency Active Auroral Research Program (HAARP) was initiated as an ionospheric research program jointly funded by the United States Air Force , the U.S. Navy, the University of Alaska Fairbanks, and the Defense Advanced Research Projects Agency (DARPA). It was designed and built by BAE Advanced Technologies (BAEAT). Its original purpose was to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance. As a university-owned facility, HAARP is a high-power, high-frequency transmitter used for study of the ionosphere. The most prominent instrument at HAARP is the Ionospheric Research Instrument (IRI), a high-power radio frequency transmitter facility operating in the high frequency (HF) band. The IRI is used to temporarily excite a limited area of the ionosphere. Other instruments, such as a VHF and a UHF radar, a fluxgate magnetometer, a digisonde (an ionospheric sounding device), and an induction magnetometer, are used to study the physical processes that occur in the excited region. Work on the HAARP facility began in 1993. The current working IRI was completed in 2007; its prime contractor was BAE Systems Advanced Technologies. As of 2008, HAARP had incurred around $250 million in tax-funded construction and operating costs. In May 2014, it was announced that the HAARP program would be permanently shut down later in the year. After discussions between the parties, ownership of the facility and its equipment was transferred to the University of Alaska Fairbanks in August 2015. HAARP is a target of conspiracy theorists, who claim that it is capable of "weaponizing" weather. Commentators and scientists say that advocates of this theory are uninformed, as claims made fall well outside the abilities of the facility, if not the scope of natural science.
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  • 21 Nov 2022
Topic Review
Reindeer Distribution
The reindeer is a widespread and numerous species in the northern Holarctic, being present in both tundra and taiga (boreal forest). Originally, the reindeer was found in Scandinavia, eastern Europe, Russia , Mongolia, and northern China north of the 50th latitude. In North America, it was found in Canada , Alaska (United States ), and the northern contiguous USA from Washington to Maine. In the 19th century, it was apparently still present in southern Idaho. It also occurred naturally on Sakhalin, Greenland, and probably even in historical times in Ireland. During the late Pleistocene era, reindeer were found further south, such as at Nevada, Tennessee , and Alabama in North America and Spain in Europe. Today, wild reindeer have disappeared from many areas within this large historical range, especially from the southern parts, where it vanished almost everywhere. Populations of wild reindeer are still found in Norway , Finland , Siberia, Greenland, Alaska, and Canada . Domesticated reindeer are mostly found in northern Fennoscandia and Russia, with a herd of approximately 150–170 semi-domesticated reindeer living around the Cairngorms region in Scotland. The last remaining wild tundra reindeer in Europe are found in portions of southern Norway . A few reindeer from Norway were introduced to the South Atlantic island of South Georgia in the beginning of the 20th century. The South Georgian reindeer totaled some estimated 2600 animals in two distinct herds separated by glaciers. Although the flag and the coat of arms of the territory contain an image of a reindeer, they were eradicated from 2013 to 2017 because of the environmental damage they caused. Around 4000 reindeer have been introduced into the French sub-Antarctic archipelago of Kerguelen Islands. East Iceland has a small herd of about 2500–3000 animals. Caribou and reindeer numbers have fluctuated historically, but many herds are in decline across their range. This global decline is linked to climate change for northern, migratory caribou and reindeer herds and industrial disturbance of caribou habitat for sedentary, non-migratory herds.
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  • 28 Nov 2022
Topic Review
Accretion (Astrophysics)
In astrophysics, accretion is the accumulation of particles into a massive object by gravitationally attracting more matter, typically gaseous matter, in an accretion disk. Most astronomical objects, such as galaxies, stars, and planets, are formed by accretion processes.
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  • 11 Nov 2022
Topic Review
Product Distribution
A product distribution is a probability distribution constructed as the distribution of the product of random variables having two other known distributions. Given two statistically independent random variables X and Y, the distribution of the random variable Z that is formed as the product is a product distribution.
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  • 11 Nov 2022
Topic Review
Five Precepts
The five precepts (Pali: pañcasīla; Sanskrit: pañcaśīla) or five rules of training (Pali: pañcasikkhapada; Sanskrit: pañcaśikṣapada) is the most important system of morality for Buddhist lay people. They constitute the basic code of ethics undertaken by lay followers of Buddhism. The precepts are commitments to abstain from killing living beings, stealing, sexual misconduct, lying and intoxication. Within the Buddhist doctrine, they are meant to develop mind and character to make progress on the path to enlightenment. They are sometimes referred to as the śrāvakayāna precepts in the Mahāyāna tradition, contrasting them with the bodhisattva precepts. The five precepts form the basis of several parts of Buddhist doctrine, both lay and monastic. With regard to their fundamental role in Buddhist ethics, they have been compared with the ten commandments in Christianity or the ethical codes of Confucianism. The precepts have been connected with utilitarianist, deontological and virtue approaches to ethics. They have been compared with human rights because of their universal nature, and some scholars argue they can complement the concept of human rights. The five precepts were common to the religious milieu of 6th-century BCE India, but the Buddha's focus on awareness through the fifth precept was unique. As shown in Early Buddhist Texts, the precepts grew to be more important, and finally became a condition for membership of the Buddhist religion. When Buddhism spread to different places and people, the role of the precepts began to vary. In countries where Buddhism had to compete with other religions, such as China, the ritual of undertaking the five precepts developed into an initiation ceremony to become a Buddhist lay person. On the other hand, in countries with little competition from other religions, such as Thailand, the ceremony has had little relation to the rite of becoming Buddhist, as many people are presumed Buddhist from birth. Undertaking and upholding the five precepts is based on the principle of non-harming (Pāli and Sanskrit: ahiṃsa). The Pali Canon recommends one to compare oneself with others, and on the basis of that, not to hurt others. Compassion and a belief in karmic retribution form the foundation of the precepts. Undertaking the five precepts is part of regular lay devotional practice, both at home and at the local temple. However, the extent to which people keep them differs per region and time. People keep them with an intention to develop themselves, but also out of fear of a bad rebirth. The first precept consists of a prohibition of killing, both humans and all animals. Scholars have interpreted Buddhist texts about the precepts as an opposition to and prohibition of capital punishment, suicide, abortion and euthanasia. In practice, however, many Buddhist countries still use the death penalty. With regard to abortion, Buddhist countries take the middle ground, by condemning though not prohibiting it. The Buddhist attitude to violence is generally interpreted as opposing all warfare, but some scholars have raised exceptions. The second precept prohibits theft. The third precept refers to adultery in all its forms, and has been defined by modern teachers with terms such as sexual responsibility and long-term commitment. The fourth precept involves falsehood spoken or committed to by action, as well as malicious speech, harsh speech and gossip. The fifth precept prohibits intoxication through alcohol, drugs or other means. Early Buddhist Texts nearly always condemn alcohol, and so do Chinese Buddhist post-canonical texts. Buddhist attitudes toward smoking differ per time and region, but are generally permissive. In modern times, traditional Buddhist countries have seen revival movements to promote the five precepts. As for the West, the precepts play a major role in Buddhist organizations. They have also been integrated in mindfulness training programs, though many mindfulness specialists do not support this because of the precepts' religious import. Lastly, many conflict prevention programs make use of the precepts.
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  • 22 Nov 2022
Topic Review
Wife
A wife is a female partner in a continuing marital relationship. The term continues to be applied to a woman who has separated from her partner, and ceases to be applied to such a woman only when her marriage has come to an end, following a legally recognized divorce or the death of her spouse. On the death of her partner, a wife is referred to as a widow, but not after she is divorced from her partner. The rights and obligations of a wife in relation to her partner and her status in the community and in law vary between cultures and have varied over time.
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  • 17 Nov 2022
Topic Review
List of Human Spaceflight Programs
This is a list of human spaceflight programs, including successful programs, programs that were canceled, and programs planned for the future. The criteria for what constitutes human spaceflight vary. The FAI defines spaceflight as any flight over 100 kilometers (62 mi). In the U.S. professional, military, and commercial astronauts who travel above an altitude of 80 kilometers (50 mi) are awarded astronaut wings. This article follows the FAI definition of spaceflight. Until the 21st century, human spaceflight programs were sponsored exclusively by governments, through either the military or civilian space agencies. With the launch of the privately funded SpaceShipOne in 2004, a new category of human spaceflight programs – commercial human spaceflight – arrived.
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  • 09 Nov 2022
Topic Review
Rice Husk
The development of engineered silica particles by using low-cost renewable or waste resources is a key example of sustainability. Rice husks have emerged as a renewable resource for the production of engineered silica particles as well as bioenergy.
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  • 17 Jan 2022
Topic Review
E-learning (Theory)
E-learning theory describes the cognitive science principles of effective multimedia learning using electronic educational technology.
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  • 25 Nov 2022
Topic Review
Tin Can
A tin can, tin (especially in British English, Australian English and Canadian English), steel can, steel packaging or a can, is a container for the distribution or storage of goods, composed of thin metal. Many cans require opening by cutting the "end" open; others have removable covers. Cans hold diverse contents: foods, beverages, oil, chemicals, etc. Steel cans are made of tinplate (tin-coated steel) or of tin-free steel. In some dialects, even aluminium cans are called "tin cans".
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  • 26 Oct 2022
Topic Review
Friends with Benefits Relationships
Friends with benefits relationships (FWB or FWBR) is a term commonly used to reference a relationship that is sexual without being romantic. Typically, these relationships can be between people that consider themselves platonic friends without pressure. These non-committal relationships can be short term, or evolve into serious romantic relationships. In an era of increased sexual liberation, casual sexual relationships continue to become more prominent. Studies show an increasing number of college students, both male and female, report having a friends with benefits relationship at some point. FWB relationships are enjoyed by both women and men, this is in contrast to casual sexual encounters which are more prevalent among men.
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  • 27 Oct 2022
Topic Review
Deformation (Engineering)
In engineering, deformation refers to the change in size or shape of an object. Displacements are the absolute change in position of a point on the object. Deflection is the relative change in external displacements on an object. Strain is the relative internal change in shape of an infinitesimally small cube of material and can be expressed as a non-dimensional change in length or angle of distortion of the cube. Strains are related to the forces acting on the cube, which are known as stress, by a stress-strain curve. The relationship between stress and strain is generally linear and reversible up until the yield point and the deformation is elastic. The linear relationship for a material is known as Young's modulus. Above the yield point, some degree of permanent distortion remains after unloading and is termed plastic deformation. The determination of the stress and strain throughout a solid object is given by the field of strength of materials and for a structure by structural analysis. Engineering stress and engineering strain are approximations to the internal state that may be determined from the external forces and deformations of an object, provided that there is no significant change in size. When there is a significant change in size, the true stress and true strain can be derived from the instantaneous size of the object. In the figure it can be seen that the compressive loading (indicated by the arrow) has caused deformation in the cylinder so that the original shape (dashed lines) has changed (deformed) into one with bulging sides. The sides bulge because the material, although strong enough to not crack or otherwise fail, is not strong enough to support the load without change. As a result, the material is forced out laterally. Internal forces (in this case at right angles to the deformation) resist the applied load. The concept of a rigid body can be applied if the deformation is negligible.
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  • 24 Oct 2022
Topic Review
Broadcasting of Sports Events
The broadcasting of sports events (also known as a sportscast) is the live coverage of sports as a television program, on radio, and other broadcasting media. It usually involves one or more sports commentators describing events as they happen.
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  • 01 Dec 2022
Topic Review
Medium-Voltage Switchgear Condition Monitoring
Switchgear are a key component of the electrical grid. They serve both protective and control roles in distribution electric power with in the grid. It is therefore important to monitor and predict the condition of these assets. Thereby, condition monitoring is divided into three main tasks: breaker drive monitoring, thermal monitoring and partial discharge monitoring. This encyclopedia article provides an overview of the potential failure modes and monitoring techniques. More details can be found in an exhaustive review article, cited below.
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  • 29 Oct 2020
Topic Review
Impulse Buying Behavior in Fast Fashion Physical Stores
The health crisis caused by COVID-19 has affected consumption and payment patterns worldwide. Consumers have had to change their habits and deal with new sanitation guidelines and have often struggled with lengthy infrastructure closures. These factors significantly influenced both the choice of payment methods and purchase decisions made by consumers. Still, consumption patterns during the pandemic as a new social situation have not yet been thoroughly investigated. 
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  • 22 Apr 2022
Topic Review
An Insight into Psychedelic Drugs in Schizophrenia
Schizophrenia remains a serious chronic mental illness since its revelation more than a century ago by Dr. Emile Kraepelin. Despite the low prevalence, nearly 24 million people suffer from this disorder, which constitutes 1 in 300 people (0.32%) of the world’s population and this rate is 1 in 222 people (0.45%) among adults. The symptoms of schizophrenia more often appear in the second or third decade of life, and disease occurrence is tied to a combination of factors such as genetic, socio-demographic, and environmental factor. Clinical schizophrenia is presented in two unique and distinct sets of symptomatology, which include ‘positive’ symptoms and ‘negative’ symptoms, and is also accompanied by significant impairment of cognitive functioning in one or more major areas. This may include an inability to execute work, interpersonal relations, or self-care, and there is also a failure to achieve the expected level of interpersonal, academic, or occupational functioning. According to the current Diagnostic and Statistical Manual for mental disorders-V (DSM-V), the positive symptoms of schizophrenia are delusions, hallucinations, disorganized speech, and behaviour; and the negative symptoms are diminished emotional expression or avolitio. These symptoms have been found to be chronically present once the disease starts, but generally the illness is marked as alternate signs of remission and exacerbation or partial remission or exacerbation. Some psychotic symptoms may be treated without the need for medication with proper human care, social support and care including electroconvulsive therapy.
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  • 08 Jun 2022
Topic Review
Ballad
A ballad is a form of verse, often a narrative set to music. Ballads derive from the medieval French chanson balladée or ballade, which were originally "dance songs". Ballads were particularly characteristic of the popular poetry and song of Britain and Ireland from the later medieval period until the 19th century. They were widely used across Europe, and later in Australia, North Africa, North America and South America. Ballads are often 13 lines with an ABABBCBC form, consisting of couplets (two lines) of rhymed verse, each of 14 syllables. Another common form is ABAB or ABCB repeated, in alternating 8 and 6 syllable lines. Many ballads were written and sold as single sheet broadsides. The form was often used by poets and composers from the 18th century onwards to produce lyrical ballads. In the later 19th century, the term took on the meaning of a slow form of popular love song and is often used for any love song, particularly the sentimental ballad of pop or rock music, although the term is also associated with the concept of a stylized storytelling song or poem, particularly when used as a title for other media such as a film.
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  • 04 Nov 2022
Topic Review
Intercropping
Intercropping ensures multiple benefits like enhancement of yield, environmental security, production sustainability and greater ecosystem services. In intercropping, two or more crop species are grown concurrently such that they coexist for a significant part of the crop cycle and interact among themselves and with agro-ecosystems.
  • 7.5K
  • 09 Jan 2022
Topic Review
6 February 1934 Crisis
The 6 February 1934 crisis was an anti-parliamentarist street demonstration in Paris organized by multiple far-right leagues that culminated in a riot on the Place de la Concorde, near the seat of the French National Assembly. The police shot and killed 15 demonstrators. It was one of the major political crises during the Third Republic (1870–1940). Frenchmen on the left feared it was an attempt to organize a fascist coup d'état. According to historian Joel Colton, "The consensus among scholars is that there was no concerted or unified design to seize power and that the leagues lacked the coherence, unity, or leadership to accomplish such an end." As a result of the actions of that day, several anti-fascist organisations were created, such as the Comité de vigilance des intellectuels antifascistes, in an attempt to thwart the rise of fascism in France. After World War II, several historians, among them Serge Berstein, argued that while some leagues had been indisputably pushing for a coup, François de La Rocque had, in fact, turned in a liberal direction, toward a respect for constitutional order. However, if the lack of coordination among the fascist leagues undermined the idea of a fascist conspiracy, the fascist actions on 6 February were an uncoordinated but violent attempt to overthrow the Cartel des gauches government elected in 1932. Édouard Daladier, who was president of the Council of Ministers, replaced Camille Chautemps on 27 January 1934 because of accusations of corruption (including the Stavisky Affair). Daladier, who had been a popular figure, was nonetheless forced to resign on 7 February. He was replaced by the conservative Gaston Doumergue as head of the government; this was the first time during the tenure of the Third Republic a government fell because of pressures from the street.
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  • 21 Nov 2022
Topic Review
ISO Standards for Trailer Connectors
A number of ISO standards cover trailer connectors, the electrical connectors between vehicles and the trailers they tow that provide a means of control for the trailers. These are listed below, with notes on significant deviations from them that can cause problems.
  • 7.5K
  • 07 Nov 2022
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