T-72The T-72 is a family of Soviet main battle tanks that entered production in 1969. The T-72 was a development of the T-64, which was troubled by high costs and its reliance on immature developmental technology. About 25,000 T-72 tanks have been built, and refurbishment has enabled many to remain in service for decades. It has been widely exported and has seen service in 40 countries and in numerous conflicts. The Russian T-90 introduced in 1992 and the Chinese Type 99 are further developments of the T-72.
T-44The T-44 was a medium tank first developed and produced near the end of World War II by the Soviet Union. It was the successor to the T-34, offering an improved ride and cross-country performance, along with much greater armor. Designed to be equipped with an 85 mm main gun, by the time it was fully tested the T-34 had also moved to this weapon. Both tanks offered similar performance, so introducing the T-44 was not considered as important as increasing T-34 production. Fewer than 2,000 T-44s were built, compared to about 58,000 T-34s.
Genetic engineeringGenetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA.
MartiniqueMartinique (ˌmɑːrtᵻˈniːk , maʁtinik; Matinik or Matnik; Kalinago: Madinina or Madiana) is an island which is a single territorial collectivity of the French Republic. It is also part of the European Union as an Outermost Region within the Special territories of members of the European Economic Area, but is not part of the Schengen Area and the European Union Customs Union. As part of the French (Antilles) West Indies, Martinique is located in the Lesser Antilles of the West Indies in the eastern Caribbean Sea.
Pythagorean trigonometric identityThe Pythagorean trigonometric identity, also called simply the Pythagorean identity, is an identity expressing the Pythagorean theorem in terms of trigonometric functions. Along with the sum-of-angles formulae, it is one of the basic relations between the sine and cosine functions. The identity is As usual, means . Any similar triangles have the property that if we select the same angle in all of them, the ratio of the two sides defining the angle is the same regardless of which similar triangle is selected, regardless of its actual size: the ratios depend upon the three angles, not the lengths of the sides.
National ConventionThe National Convention (Convention nationale) was the constituent assembly of the Kingdom of France for one day and the French First Republic for its first three years during the French Revolution, following the two-year National Constituent Assembly and the one-year Legislative Assembly. Created after the great insurrection of 10 August 1792, it was the first French government organized as a republic, abandoning the monarchy altogether.
Traction motorA traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, or electric multiple unit trains. Traction motors are used in electrically powered railway vehicles (electric multiple units) and other electric vehicles including electric milk floats, trolleybuses, elevators, roller coasters, and conveyors, as well as vehicles with electrical transmission systems (diesel-electric locomotives, electric hybrid vehicles), and battery electric vehicles.
Unit circleIn mathematics, a unit circle is a circle of unit radius—that is, a radius of 1. Frequently, especially in trigonometry, the unit circle is the circle of radius 1 centered at the origin (0, 0) in the Cartesian coordinate system in the Euclidean plane. In topology, it is often denoted as S1 because it is a one-dimensional unit n-sphere. If (x, y) is a point on the unit circle's circumference, then and are the lengths of the legs of a right triangle whose hypotenuse has length 1.
Traction (engineering)Traction, or tractive force, is the force used to generate motion between a body and a tangential surface, through the use of dry friction, though the use of shear force of the surface is also commonly used. Traction can also refer to the maximum tractive force between a body and a surface, as limited by available friction; when this is the case, traction is often expressed as the ratio of the maximum tractive force to the normal force and is termed the coefficient of traction (similar to coefficient of friction).
Lo-fi musicLo-fi (also typeset as lofi or low-fi; short for low fidelity) is a music or production quality in which elements usually regarded as imperfections in the context of a recording or performance are present, sometimes as a deliberate choice. The standards of sound quality (fidelity) and music production have evolved throughout the decades, meaning that some older examples of lo-fi may not have been originally recognized as such. Lo-fi began to be recognized as a style of popular music in the 1990s, when it became alternately referred to as DIY music (from "do it yourself").
L-systemAn L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar. An L-system consists of an alphabet of symbols that can be used to make strings, a collection of production rules that expand each symbol into some larger string of symbols, an initial "axiom" string from which to begin construction, and a mechanism for translating the generated strings into geometric structures. L-systems were introduced and developed in 1968 by Aristid Lindenmayer, a Hungarian theoretical biologist and botanist at the University of Utrecht.
