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Topic Review
Chi-Square Distribution
In probability theory and statistics, the chi-square distribution (also chi-squared or χ2-distribution) with k degrees of freedom is the distribution of a sum of the squares of k independent standard normal random variables. The chi-square distribution is a special case of the gamma distribution and is one of the most widely used probability distributions in inferential statistics, notably in hypothesis testing and in construction of confidence intervals. This distribution is sometimes called the central chi-square distribution, a special case of the more general noncentral chi-square distribution. The chi-square distribution is used in the common chi-square tests for goodness of fit of an observed distribution to a theoretical one, the independence of two criteria of classification of qualitative data, and in confidence interval estimation for a population standard deviation of a normal distribution from a sample standard deviation. Many other statistical tests also use this distribution, such as Friedman's analysis of variance by ranks.
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  • 11 Nov 2022
Topic Review
Free State (Government)
Free state is a term that has been occasionally used in the official titles of some states. In principle, the title asserts and emphasises a particular freedom of the state in question, but this is not always reflected in practice, and what "free state" actually means varies greatly in different contexts:  Sometimes it asserts sovereignty or independence (and with that, lack of foreign domination). Sometimes it asserts autonomy within a larger nation-state. Sometimes it is used as a synonym for republic, but not all "free states" have been republics. While the historical German free states and the Orange Free State were republican in form, the Congo Free State and Irish Free State were governed under forms of monarchy. The republican sense derives from libera res publica (literally, "the free public thing/affair"), a term used by Roman historians for the period of the Roman Republic.
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  • 11 Nov 2022
Biography
Ravidas
Ravidas was an India n mystic poet-sant of the Bhakti movement of Sri Hari and his incarnations like Rama, Krishna such as Namdev, Meerabai and founder of Ravidassia sect during the 15th to 16th century CE.[1][2] Venerated as a guru (teacher) in the region of Uttar Pradesh, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh and mainly Punjab and Haryana. He was a poet-saint, social reformer and a s
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  • 15 Nov 2022
Biography
Ishfaq Ahmad
Ishfaq Ahmad, D.Sc., Minister of State, SI, HI, NI, FPAS (3 November 1930 – 18 January 2018), was a Pakistani nuclear physicist, emeritus professor of high-energy physics at the National Center for Physics, and former science advisor to the Government of Pakistan.[1] A versatile theoretical physicist,[2] Ahmad made significant contributions in the theoretical development of the applications a
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Topic Review
Election Threshold
The electoral threshold is the minimum share of the primary vote which a candidate or political party requires to achieve before they become entitled to any representation in a legislature. This limit can operate in various ways. For example, in party-list proportional representation systems, an election threshold requires that a party must receive a specified minimum percentage of votes (e.g., 5%), either nationally or in a particular electoral district, to obtain any seats in the legislature. In multi-member constituencies using preferential voting, besides the electoral threshold, to be awarded a seat, a candidate is also required to achieve a quota, either on the primary vote or after distribution of preferences, which depends on the number of members to be return from a constituency. The effect of an electoral threshold is to deny representation to small parties or to force them into coalitions, with the presumption of rendering the election system more stable by keeping out fringe parties. However, critics argue out that in the absence of a ranked ballot system, supporters of minor parties are effectively disenfranchised and denied the right of representation by someone of their choosing. Two boundaries can be defined: a threshold of representation is the minimum vote share that might yield a party a seat (under the most favorable circumstances for the party), while the threshold of exclusion is the maximum vote share that could be insufficient to yield a seat (under the least favorable circumstances). Lijphart suggested calculating the informal threshold as the mean of these.
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Topic Review
List of Geological Groups of Great Britain
This is a sortable list of the groups into which the rock succession of Great Britain and surrounding seas is formally divided. Rock sequences are described by geologists by dividing them hierarchically thus: individual 'beds' of rock (or in the case of certain volcanic rocks, 'flows') are grouped into 'members', members are grouped into 'formations', formations into 'groups' and groups occasionally into 'supergroups'. Some groups are also subdivided into 'subgroups'. Not all of these hierarchical layers are necessarily present or defined within a particular rock succession. Many of these groups will be encountered as 'series' in older geological literature or indeed simply as the proper name e.g. 'Dalradian' or 'Millstone Grit' though care needs to be exercised as many of the names have or have had other meanings which may not coincide with the assemblage of rocks referred to formally through designation as a 'group'. Note that with all such stratigraphical terms as 'groups', 'formations' and 'members' it is standard practice to capitalise both the proper name and the 'term-word' as per the recommendation of the International Commission on Stratigraphy e.g. Wentnor Group and not Wentnor group. Notes:
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Topic Review
Nehru Memorial Museum & Library
The Nehru Memorial Museum & Library (NMML) is a museum and library in New Delhi, India , which aims to preserve and reconstruct the history of the Indian independence movement. Housed within the Teen Murti House complex, it is an autonomous institution under the Indian Ministry of Culture, and was founded in 1964 after the death of India's first prime minister, Jawaharlal Nehru. It aims to foster academic research on modern and contemporary history. Today, the Nehru Memorial Library is the world’s leading resource centre on India’s first prime minister. Its archives contain the bulk of Mahatma Gandhi's writings, as well as private papers of C. Rajagopalachari, B. C. Roy, Jayaprakash Narayan, Charan Singh, Sarojini Naidu and Rajkumari Amrit Kaur. In March 2010 it launched a digitization project of its archives, and by June 2011, 867,000 pages of manuscripts and 29,807 photographs had been scanned and 500,000 pages had been uploaded on the digital library website. Amongst noted publications of the NMML are Selected Works of Jawaharlal Nehru, Man of Destiny by Ruskin Bond, Nehru Anthology (1980) and Nehru Anthology. Nehru Memorial Museum & Library has over the years supported scholars and historians across India. Through its fellowship programme, the Nehru Memorial Fellowship, it has funded some of India’s best academics such as Chief Information Commissioner OP Kejriwal. It is also one of the best libraries in Delhi for the social sciences as it has a huge collection on labour related issues in the form of PhD dissertations, reports, books, journals and news papers. On 26 April 2016 a dagger gifted to former prime minister Jawaharlal Nehru by Saudi Arabia was stolen from the Nehru Memorial Museum and Library.
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Topic Review
Cartographic Labeling
{{Multiple issues| Cartographic labeling is a form of typography and strongly deals with form, style, weight and size of type on a map. Essentially, labeling denotes the correct way to label features (points, arcs, or polygons).
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  • 11 Nov 2022
Topic Review
Advanced Nuclear
Advanced nuclear is an emerging area of the energy industry focused on designing and commercializing next generation reactors for nuclear energy production. Encompassing more comprehensive and radical technological innovations and design advancements, these innovations aim to dramatically improve performance and eliminate known problems associated with the existing generation nuclear reactors (Gen I and Gen II) currently in use around the world. The earliest Gen I and Gen II nuclear reactors built utilized the light-water reactor design in one of three variants: the pressurized water reactor (PWR), the boiling water reactor (BWR), and the supercritical water reactor (SCWR). The use of the light-water design (i.e. using regular water, H2O and not heavy water, 2H2O) as both its coolant and neutron moderator but needing a plentiful supply) in all commercial reactors was a trade-off that enabled the industry to leverage the purchasing clout of Admiral Hyman G. Rickover, who was keen on procuring nuclear-powered submarines for the Navy, to grow quickly. The choice, however, imposed a riskier design that many argued was not optimized for terrestrial energy, bringing both competitive advantages as well as fateful disadvantages to the initial development and subsequent growth of the commercial nuclear power fleet. Despite operating to the military's exacting specifications and winning praise and massive contracts from government buyers, the industry quickly earned the distrust of the public. (See the Anti-nuclear movement.) Generation III reactors contain yet further incremental refinements to aspects of Generation II nuclear reactor designs but were not very popular. Improvements were developed for fuel technology, thermal efficiency, to safety systems to reduce maintenance and capital costs. The first Generation III reactor was Kashiwazaki 6 (an ABWR) in 1996 but the declining support for the underlying Generation II light-water design, caused relatively few third generation reactors to be built. Generation IV designs are the first generation where innovator in Advanced Nuclear technologies are exploring paradigm shifts in methodologies. Gen IV projects encompass not just innovative nuclear fission concepts, like the Molten salt reactor, Liquid Metal Fast Breeder Reactors, and High temperature gas cooled reactors, but also Fusion power and even Low Energy Nuclear Reactors (LENR), which generate heat through a series of controlled chemical reactions that then cause a nuclear bond to shift, which results in heat output. Gen IV is still in development as of 2017, and are not expected to start entering commercial operation until after 2020. Some of the different reactor design ideas being explored and developed for Advanced nuclear reactors, now thought of as Generation IV reactors (Gen IV) today were actually first conceived within the National Labs back in the 1960s. Several of these concepts, including Alvin M. Weinberg's Molten salt reactor (MSR) developed at the Oak Ridge National Laboratory (ORNL), even had the benefit of being prototyped and tested over a period of time. Weinberg's MSR became the first reactor to run on Uranium 233 in 1968 and logged more than 13,000 hours at "full power" before being shut down in 1969. Today, the concept of using a molten salt brew that acts both as the fuel and the "containment" of the reaction by using the ionic bonds of the salt to capture and contain the heat generated from the nuclear reaction, thereby dispensing with the need for expensive containment structures and eliminating much of risk and cost, remains of keen interest to those exploring Advanced nuclear technologies.
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Topic Review
State of Nature
The state of nature, in moral and political philosophy, religion, social contract theories and international law, is the hypothetical life of people before societies came into existence. Philosophers of the state of nature theory deduce that there must have been a time before organized societies existed, and this presumption thus raises questions such as: "What was life like before civil society?"; "How did government first emerge from such a starting position?," and; "What are the hypothetical reasons for entering a state of society by establishing a nation-state?". In some versions of social contract theory, there are no rights in the state of nature, only freedoms, and it is the contract that creates rights and obligations. In other versions the opposite occurs: the contract imposes restrictions upon individuals that curtail their natural rights. Societies existing before or without a political state are currently studied in such fields as paleolithic history, and the anthropological subfields of archaeology, cultural anthropology, social anthropology, and ethnology, which investigate the social and power-related structures of indigenous and uncontacted peoples living in tribal communities.
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