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Polar Semiconductor
Polar may refer to: Geography * Geographical pole, either of the two points on Earth where its axis of rotation intersects its surface ** Polar climate, the climate common in polar regions ** Polar regions of Earth, locations within the polar circles, referred to as the Arctic and Antarctic Places * Polar, Wisconsin, town in Langlade County, Wisconsin, United States ** Polar (community), Wisconsin, unincorporated community in Langlade County, Wisconsin, United States Arts, entertainment and media * ''Polar'' (webcomic), a webcomic and series of graphic novels by Víctor Santos * ''Polar'' (film), a 2019 Netflix film adaption of the above comic series * ''Polar'', a 2002 novel by T. R. Pearson Music * Polar Music, a record label * Polar Studios, music studio of ABBA in Sweden * ''Polar'' (album), second album by the High Water Marks * ''Polars'' (album), an album by the Dutch metal band, Textures Brands and enterprises * Polar Air Cargo, an American airline * Polar Airline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographical Pole
A geographical pole or geographic pole is either of the two points on Earth where its axis of rotation intersects its surface. The North Pole lies in the Arctic Ocean while the South Pole is in Antarctica. North and South poles are also defined for other planets or satellites in the Solar System, with a North pole being on the same side of the invariable plane as Earth's North pole. Relative to Earth's surface, the geographic poles move by a few metres over periods of a few years. This is a combination of Chandler wobble, a free oscillation with a period of about 433 days; an annual motion responding to seasonal movements of air and water masses; and an irregular drift towards the 80th west meridian (geography), meridian. As cartography requires exact and unchanging coordinates, the averaged locations of geographical poles are taken as fixed ''cartographic poles'' and become the points where the body's great circles of longitude intersect. See also * Earth's rotation * Polar mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Question
In linguistics, a yes–no question, also known as a binary question, a polar question, or a general question, is a closed-ended question whose expected answer is one of two choices, one that provides an affirmative answer to the question versus one that provides a negative answer to the question. Typically, the choices are either "yes" or "no" in English. Yes–no questions present an exclusive disjunction, namely a pair of alternatives of which only one is a felicitous answer. In English, such questions can be formed in both positive and negative forms: * positive yes/no question: "Will you be here tomorrow?" * negative yes/no question: "Won't you be here tomorrow?" Yes–no questions are in contrast with non-polar wh-questions. The latter are also called content questions, and are formed with the five Ws plus an H ("who", "what", "where", "when", "why", "how"). Rather than restricting the range of possible answers to two alternatives, content questions are compatible with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Organelle
A polar organelle is a structure at a specialized region of the bacterial polar membrane that is associated with the flagellar apparatus. This flagellum-associated structure can easily be distinguished from the other membrane regions in ultra-thin sections of embedded bacteria by electron microscopy when the cell membrane is orientated perpendicular to the viewing direction. There, the membrane appears slightly thickened with a finely frilled layer facing the inside of the cell. It is also possible to isolate these polar organelles from the bacterial cells and study them in face view in negatively stained preparations. The polar organelle bears a fine array of attached particles in hexagonal close packing and these have been shown to possess ATPase activity. The polar organelle is found in close juxtaposition to the points of insertion of the bacterial flagella into the plasma membrane, especially where multiple flagella bases are grouped in a region of the cell membrane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Fleece
Polar fleece is a soft fabric made from polyester that is napped and insulating. PolarFleece is a trademark registered by Malden Mills (now Polartec, LLC) with the United States Patent and Trademark Office on October 6, 1981. Malden Mills developed polar fleece in 1979. Uses Polar fleece is used in jackets, hats, sweaters, sweatpants, cloth diapers (nappies), gym clothes, hoodies, pajamas, blankets, and high-performance outdoor clothing. The produced fleece can be used to create clothes that are very light, soft, and easy to wash. Polar fleece can stretch more easily in one direction than in others. History Polar fleece originated in Massachusetts in 1979 when Malden Mills and Patagonia developed Synchilla (synthetic chinchilla). It was a new, light, strong pile fabric meant to mimic, and in some ways surpass, wool. Malden Mills CEO Aaron Feuerstein intentionally declined to patent polar fleece, allowing the material to be produced cheaply and widely by many vendors, lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Curve (aviation)
The drag curve or drag polar is the relationship between the Drag (physics)#Aerodynamics, drag on an aircraft and other variables, such as lift, the coefficient of lift, angle-of-attack or speed. It may be described by an equation or displayed as a graph (sometimes called a "polar plot"). Drag may be expressed as actual drag or the coefficient of drag. Drag curves are closely related to other curves which do not show drag, such as the power required/speed curve, or the sink rate/speed curve. The drag curve The significant aerodynamic properties of aircraft wings are summarised by two Dimensionless quantity, dimensionless quantities, the lift coefficient, lift and drag coefficients and . Like other such aerodynamic quantities, they are functions only of the angle of attack , the Reynolds number and the Mach number . and can be plotted against , or can be plotted against each other. The lift and the drag forces, and , are scaled by the same factor to get and , so = . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POLAR III
POLAR III is a pedestrian test dummy created by Honda. The dummy is used to study how pedestrians are injured or killed when hit by automobiles. POLAR III has instruments to measure the level of injury throughout the body. About 5,000 pedestrians are killed in traffic accidents each year in the United States. By studying test dummy results and designing cars in such a way as to protect pedestrians as much as possible in the event of a collision, the number of fatalities and injuries due to pedestrians being struck may be reduced. See also * Crash test dummy * Pedestrian safety through vehicle design References POLAR IIICross member* ''National Geographic ''National Geographic'' (formerly ''The National Geographic Magazine'', sometimes branded as ''Nat Geo'') is an American monthly magazine published by National Geographic Partners. The magazine was founded in 1888 as a scholarly journal, nine ...'' Magazine, July 2005 Vehicle safety technologies Automotive safety Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Polarity
In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar bonds due to a difference in electronegativity between the bonded atoms. Molecules containing polar bonds have no molecular polarity if the bond dipoles cancel each other out by symmetry. Polar molecules interact through dipole-dipole intermolecular forces and hydrogen bonds. Polarity underlies a number of physical properties including surface tension, solubility, and melting and boiling points. Polarity of bonds Not all atoms attract electrons with the same force. The amount of "pull" an atom exerts on its electrons is called its electronegativity. Atoms with high electronegativitiessuch as fluorine, oxygen, and nitrogenexert a greater pull on electrons than atoms with lower electronegativities such as alkali metals and alkaline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar (satellite)
The Global Geospace Science (GGS) ''Polar'' satellite was a NASA science spacecraft designed to study the polar magnetosphere and aurorae. It was launched into orbit in February 1996, and continued operations until the program was terminated in April 2008. The spacecraft remains in orbit, though it is now inactive. ''Polar'' is the sister ship to GGS ''Wind''. Launch It was designed and manufactured by Lockheed Martin, and launched at 11:23:59.997 UTC on February 24, 1996, aboard a McDonnell Douglas Delta II 7925-10 rocket from launch pad 2W at Vandenberg Air Force Base in Lompoc, California, to study the polar magnetosphere. The spacecraft was placed into a highly elliptical orbit with apogee at 9 Earth radii and perigee at 1.8 Earth radii (geocentric), 86 degrees inclination, with a period of around 18 hours. The apogee was initially over the northern polar region, but has since been precessing south at about 16° per year. Operations Sensors on the spacecraft gathered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar (star)
In astronomy, a polar is a highly magnetic type of cataclysmic variable (CV) binary star system, originally known as an AM Herculis star after the prototype member AM Herculis. Like other CVs, polars contain two stars: an accreting white dwarf (WD), and a low-mass donor star (usually a red dwarf) which is transferring mass to the WD as a result of the WD's gravitational pull, overflowing its Roche lobe. Polars are distinguished from other CVs by the presence of a very strong magnetic field in the WD. Typical magnetic field strengths of polar systems are 10 million to 80 million gauss (1000–8000 teslas). The WD in the polar AN Ursae Majoris has the strongest known magnetic field among cataclysmic variables, with a field strength of 230 million gauss (23 kT). Accretion mechanism One of the most critical consequences of the WD's magnetism is that it synchronizes the rotational period of the WD with the orbital period of the binary; to first order, this means that th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Set
In functional and convex analysis, and related disciplines of mathematics, the polar set A^ is a special convex set associated to any subset A of a vector space X, lying in the dual space X^. The bipolar of a subset is the polar of A^\circ, but lies in X (not X^). Definitions There are at least three competing definitions of the polar of a set, originating in projective geometry and convex analysis. In each case, the definition describes a duality between certain subsets of a pairing of vector spaces \langle X, Y \rangle over the real or complex numbers (X and Y are often topological vector spaces (TVSs)). If X is a vector space over the field \mathbb then unless indicated otherwise, Y will usually, but not always, be some vector space of linear functionals on X and the dual pairing \langle \cdot, \cdot \rangle : X \times Y \to \mathbb will be the bilinear () defined by \langle x, f \rangle := f(x). If X is a topological vector space then the space Y will usually, but no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Curve
In algebraic geometry, the first polar, or simply polar of an algebraic plane curve ''C'' of degree ''n'' with respect to a point ''Q'' is an algebraic curve of degree ''n''−1 which contains every point of ''C'' whose tangent line passes through ''Q''. It is used to investigate the relationship between the curve and its dual, for example in the derivation of the Plücker formulas. Definition Let ''C'' be defined in homogeneous coordinates by ''f''(''x, y, z'') = 0 where ''f'' is a homogeneous polynomial of degree ''n'', and let the homogeneous coordinates of ''Q'' be (''a'', ''b'', ''c''). Define the operator :\Delta_Q = a+b+c. Then Δ''Q''''f'' is a homogeneous polynomial of degree ''n''−1 and Δ''Q''''f''(''x, y, z'') = 0 defines a curve of degree ''n''−1 called the ''first polar'' of ''C'' with respect of ''Q''. If ''P''=(''p'', ''q'', ''r'') is a non-singular point on the curve ''C'' then the equation of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Coordinate System
In mathematics, the polar coordinate system specifies a given point in a plane by using a distance and an angle as its two coordinates. These are *the point's distance from a reference point called the ''pole'', and *the point's direction from the pole relative to the direction of the ''polar axis'', a ray drawn from the pole. The distance from the pole is called the ''radial coordinate'', ''radial distance'' or simply ''radius'', and the angle is called the ''angular coordinate'', ''polar angle'', or ''azimuth''. The pole is analogous to the origin in a Cartesian coordinate system. Polar coordinates are most appropriate in any context where the phenomenon being considered is inherently tied to direction and length from a center point in a plane, such as spirals. Planar physical systems with bodies moving around a central point, or phenomena originating from a central point, are often simpler and more intuitive to model using polar coordinates. The polar coordinate system i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
