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Differential Systems
Differential may refer to: Mathematics * Differential (mathematics) comprises multiple related meanings of the word, both in calculus and differential geometry, such as an infinitesimal change in the value of a function * Differential algebra * Differential calculus ** Differential of a function, represents a change in the linearization of a function *** Total differential is its generalization for functions of multiple variables ** Differential (infinitesimal) (e.g. ''dx'', ''dy'', ''dt'' etc.) are interpreted as infinitesimals ** Differential topology * Differential (pushforward) The total derivative of a map between manifolds. * Differential exponent, an exponent in the factorisation of the different ideal * Differential geometry, exterior differential, or exterior derivative, is a generalization to differential forms of the notion of differential of a function on a differentiable manifold * Differential (coboundary), in homological algebra and algebraic topology, one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential (mathematics)
In mathematics, differential refers to several related notions derived from the early days of calculus, put on a rigorous footing, such as infinitesimal differences and the derivatives of functions. The term is used in various branches of mathematics such as calculus, differential geometry, algebraic geometry and algebraic topology. Introduction The term differential is used nonrigorously in calculus to refer to an infinitesimal ("infinitely small") change in some varying quantity. For example, if ''x'' is a variable, then a change in the value of ''x'' is often denoted Δ''x'' (pronounced ''delta x''). The differential ''dx'' represents an infinitely small change in the variable ''x''. The idea of an infinitely small or infinitely slow change is, intuitively, extremely useful, and there are a number of ways to make the notion mathematically precise. Using calculus, it is possible to relate the infinitely small changes of various variables to each other mathematically us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Steering
Differential steering is the means of steering a land vehicle by applying more drive torque to one side of the vehicle than the other. Differential steering is the primary means of steering tracked vehicles, such as tanks and bulldozers, is also used in certain wheeled vehicles commonly known as skid-steer, and even implemented in some automobiles, where it is called torque vectoring, to augment steering by changing wheel direction relative to the vehicle. Differential steering is distinct from torque steer, which is usually considered a negative side effect of drive-train design choices. History A British agricultural company, Richard Hornsby & Sons, Hornsby in Grantham, developed a continuous track, which was patented in 1905. The Hornsby tractors featured a track-steer clutch arrangement. Mechanisms There are several mechanisms that have been developed to vary the torque applied to different sides of a vehicle. These include ''clutch-brake'' steering, ''braked-differe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Centrifugation
In biochemistry and cell biology, differential centrifugation (also known as differential velocity centrifugation) is a common procedure used to separate organelles and other sub-cellular particles based on their sedimentation rate. Although often applied in biological analysis, differential centrifugation is a general technique also suitable for crude purification of non-living suspended particles (e.g. nanoparticles, colloidal particles, viruses). In a typical case where differential centrifugation is used to analyze cell-biological phenomena (e.g. organelle distribution), a tissue sample is first lysed to break the cell membranes and release the organelles and cytosol. The lysate is then subjected to repeated centrifugations, where particles that sediment sufficiently quickly at a given centrifugal force for a given time form a compact "pellet" at the bottom of the centrifugation tube. After each centrifugation, the ''supernatant'' (non-pelleted solution) is removed from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Rotation
Differential rotation is seen when different parts of a rotating object move with different angular velocities (or rates of rotation) at different latitudes and/or depths of the body and/or in time. This indicates that the object is not rigid. In fluid objects, such as accretion disks, this leads to shearing. Galaxies and protostars usually show differential rotation; examples in the Solar System include the Sun, Jupiter and Saturn. Around the year 1610, Galileo Galilei observed sunspots and calculated the rotation of the Sun. In 1630, Christoph Scheiner reported that the Sun had different rotational periods at the poles and at the equator, in good agreement with modern values. Cause Stars and planets rotate in the first place because conservation of angular momentum turns random drifting of parts of the molecular cloud that they form from into rotating motion as they coalesce. Given this average rotation of the whole body, internal differential rotation is caused by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Hardening
Differential heat treatment (also called selective heat treatment or local heat treatment) is a technique used during heat treating of steel to harden or soften certain areas of an object, creating a difference in hardness between these areas. There are many techniques for creating a difference in properties, but most can be defined as either ''differential hardening'' or ''differential tempering''. These were common heat treatment techniques used historically in Europe and Asia, with possibly the most widely known example being from Japanese swordsmithing. Some modern varieties were developed in the twentieth century as metallurgical knowledge and technology rapidly increased. Differential hardening is done by either of two methods. One of them is heating the steel evenly to a red-hot temperature and then cooling part of it quickly, turning that part into very hard martensite while the rest cools more slowly and becomes softer pearlite. The other is heating only part of the steel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Blood Cell Differential
A white blood cell differential is a medical laboratory test that provides information about the types and amounts of white blood cells in a person's blood. The test, which is usually ordered as part of a complete blood count (CBC), measures the amounts of the five normal white blood cell typesneutrophils, lymphocytes, monocytes, eosinophils and basophilsas well as abnormal cell types if they are present. These results are reported as percentages and absolute values, and compared against reference ranges to determine whether the values are normal, low, or high. Changes in the amounts of white blood cells can aid in the diagnosis of many health conditions, including viral disease, viral, Pathogenic bacteria, bacterial, and parasitic disease, parasitic infections and blood disorders such as leukemia. White blood cell differentials may be performed by an automated analyzera machine designed to run laboratory tests – or manually, by examining blood smears under a microscope. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
