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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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Texture
In physical chemistry and materials science, texture is the distribution of crystallographic orientations of a polycrystalline sample (it is also part of the geological fabric). A sample in which these orientations are fully random is said to have no distinct texture. If the crystallographic orientations are not random, but have some preferred orientation, then the sample has a weak, moderate or strong texture. The degree is dependent on the percentage of crystals having the preferred orientation. Texture is seen in almost all engineered materials, and can have a great influence on materials properties. The texture forms in materials during thermo-mechanical processes, for example during production processes e.g. rolling. Consequently, the rolling process is often followed by a heat treatment to reduce the amount of unwanted texture. Controlling the production process in combination with the characterization of texture and the material's microstructure help to determine the materials properties, i.e. the processing-microstructure-texture-property relationship. Also, geologic rocks show texture due to their thermo-mechanic history of formation processes. One extreme case is a complete lack of texture: a solid with perfectly random crystallite orientation will have isotropic properties at length scales sufficiently larger than the size of the crystallites. The opposite extreme is a perfect single crystal, which likely has anisotropic properties by geometric necessity.
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  • 01 Dec 2022
Topic Review
Well-Defined
In mathematics, an expression is called well-defined or unambiguous if its definition assigns it a unique interpretation or value. Otherwise, the expression is said to be not well-defined, ill-defined or ambiguous. A function is well-defined if it gives the same result when the representation of the input is changed without changing the value of the input. For instance, if f takes real numbers as input, and if f(0.5) does not equal f(1/2) then f is not well-defined (and thus not a function). The term well-defined can also be used to indicate that a logical expression is unambiguous or uncontradictory. A function that is not well-defined is not the same as a function that is undefined. For example, if f(x) = 1/x, then the fact that f(0) is undefined does not mean that the f is not well-defined — but that 0 is simply not in the domain of f.
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  • 01 Dec 2022
Topic Review
Savoia-Marchetti SM.81
The Savoia-Marchetti SM.81 Pipistrello (Italian: bat) was the first three-engine bomber/transport aircraft serving in the Italian Regia Aeronautica. When it appeared in 1935, it represented a real step ahead in Italian military aviation: it was fast, well armed and had a long range. It proved effective during the war with Ethiopia and the Spanish Civil War. Despite being too slow to remain competitive as a bomber in the later years of World War II, it was one of the most flexible, reliable and important aircraft of the Regia Aeronautica from 1935 to 1944, and adapted to second-line duties in a wide range of tasks.
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  • 01 Dec 2022
Topic Review
North–South Divide in the World
The North–South divide (or Global North and Global South) is a socio-economic and political division of Earth popularized in the late 20th century and early 21st century. Generally, definitions of the Global North include the United States , Canada , almost all the European countries, Israel, Cyprus, Japan , Singapore, South Korea , Taiwan, Australia , and New Zealand. The Global South is made up of Africa, Latin America and the Caribbean, Pacific Islands, and the developing countries in Asia, including the Middle East. It is generally seen as home to: Brazil , India and China , which, along with Indonesia and Mexico, are the largest Southern states in terms of land area and population. The North is mostly correlated with the Western world, while the South largely corresponds with the developing countries (previously called "Third World") and Eastern world. The two groups are often defined in terms of their differing levels of wealth, economic development, income inequality, democracy, and political and economic freedom, as defined by freedom indices. States that are generally seen as part of the Global North tend to be wealthier, less unequal and considered more democratic and to be developed countries who export technologically advanced manufactured products; Southern states are generally poorer developing countries with younger, more fragile democracies heavily dependent on primary sector exports and frequently share a history of past colonialism by Northern states. Nevertheless, the divide between the North and the South is often challenged and said to be increasingly incompatible with reality. In economic terms, as of the early 21st century, the North—with one quarter of the world population—controls four-fifths of the income earned anywhere in the world. 90% of the manufacturing industries are owned by and located in the North. Inversely, the South—with three quarters of the world population—has access to one-fifth of the world income. As nations become economically developed, they may become part of definitions the "North", regardless of geographical location; similarly, any nations that do not qualify for "developed" status are in effect deemed to be part of the "South".
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  • 22 Aug 2025
Biography
Bahá'u'lláh
Bahá'u'lláh (Arabic: بهاء الله; 12 November 1817 – 29 May 1892), was a Persian religious leader and the founder of the Bahá'í Faith, which advocates universal peace and unity among all races, nations, and religions. At the age of 27, Bahá'u'lláh became a follower of the Báb, a Persian merchant who began preaching that God would soon send a new prophet similar to Jesus or Muham
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  • 16 Mar 2025
Topic Review
Shopping Hours
Customs and regulations for shopping hours for sunday (times that shops are open) vary from countries to cities.
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  • 01 Dec 2022
Biography
William V. Houston
William Vermillion Houston (January 19, 1900 – August 22, 1968) was an United States physicist who made contributions to spectroscopy, quantum mechanics, and solid-state physics as well as being a teacher and administrator. He became the second president of Rice University in 1946. His family name is pronounced HOW-stun, in contrast to the pronunciation of the city of Houston in which he live
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  • 01 Dec 2022
Topic Review
IKCO EF Engines
IKCO EF engines are a family of four-cylinder engines. The EF7 series are designed jointly by Iran Khodro Powertrain Company (IPCO) and F.E.V GmbH of Germany. The other models will be designed by IPCO itself. IPCO is the powertrain designing & producing company of Iranian car manufacturer Iran Khodro (IKCO). IKCO aims to supply 800,000 powertrains by 2010. The first phase of IKCO EF Engines project (EF7 Dual-Fuel) investments were about 80 million US$. EF4 & EF7 engines use CNG as their main fuel and they can also use gasoline. EFD is the first engine of the EF family that is single-fuel. It uses high-quality diesel (Euro 4 Quality or better) as fuel. EF engines share most of their parts between them. It was IKCO's aim to reduce costs and provide ease of supplying the parts in the future for after-sales services. The EF family dual-fuel and petrol-fuel engines have achieved the Euro IV emission standard and are able to achieve Euro V emission standard with some minor changes but EFD will be the first engine of the family which comes with the Euro IV emission standard as its first release, and is able to achieve the Euro VI emission standard with some changes. The most important suppliers for EF engines are INA for sensitive VVT parts and some other mechanical parts, MAHLE which supplies some important parts of the engine family such as pistons, with Bosch supplying the ECU and electrically controlled pedal and lots of other important sensitive electronic parts. Almost all of the parts (except high-tech and sensitive parts) from worldwide well-known companies (as mentioned) are produced in Iran under license with the highest required quality for the engines. The Germany company Bosch had shown interest in assembling the Iranian engine under license. In 2008 IKCO has announced that EF7 is among the three best CNG-based engines of the world in designing.
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  • 01 Dec 2022
Topic Review
Physical Law
A physical law or a law of physics is a statement "inferred from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present." Physical laws are typically conclusions based on repeated scientific experiments and observations over many years and which have become accepted universally within the scientific community. The production of a summary description of our environment in the form of such laws is a fundamental aim of science. These terms are not used the same way by all authors. The distinction between natural law in the political-legal sense and law of nature or physical law in the scientific sense is a modern one, both concepts being equally derived from physis, the Greek word (translated into Latin as natura) for nature.
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  • 01 Dec 2022
Topic Review
IAM RoadSmart
IAM RoadSmart formerly called the Institute of Advanced Motorists (IAM) is a charity based in the United Kingdom and serving nine countries, whose objective is to improve car driving and motorcycle riding standards, and so enhance road safety, by using the British police's system of car and motorcycle control commonly known as "the System". The System was devised in 1937 by racing driver Mark Everard Pepys, 6th Earl of Cottenham, to reduce accidents in police pursuits. People who have passed an IAM test have substantially fewer accidents and typically report getting more pleasure from driving too. Research has shown that IAM training increases a wide range of driving skills, including speed, safe distances, gear changing and cornering. The IAM was formed in 1956 and has over 82,000 members, all of whom have taken and passed an advanced test in a car, commercial vehicle or on a motorcycle. In 2006, the charity took over the work of the AA Motoring Trust, which had been established in 2002 by The Automobile Association. The charity brought its different activities and programmes together under one umbrella called IAM RoadSmart in 2016.
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  • 01 Dec 2022
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