Dynamicvoltagescaling is a power management technique in computer architecture , where the voltage used in a component is increased or decreased, depending upon circumstances. Dynamicvoltagescaling to increase voltage is known as overvolting dynamicvoltagescaling to decrease voltage is known as undervolting ... completely off. This is not usually viewed as being dynamicvoltagescaling, because it is not transparent .... This again highlights why dynamicvoltagescaling is generally done in conjunction with dynamic ... power. System stability Dynamic frequency scaling is another power conservation technique that works on the same principles as dynamicvoltagescaling. Both dynamicvoltagescaling and dynamic ... voltagescaling is widely used as part of strategies to manage switching power consumption in battery ... overvolting is also used to refer to increasing static operating voltage of computer components ... using voltages at circuit nodes to represent logical state. The voltage at these nodes switches between a high voltage and a low voltage during normal operation&mdash when the inputs to a logic gate ... for a given current to effect a given voltage change. The capacitance arises from various sources ... coupling capacitance . Toggling a voltage at a circuit node requires charging or discharging the capacitance at that node since currents are related to voltage, the time it takes depends on the voltage applied. By applying a higher voltage to the devices in a circuit, the capacitances are charged ... frequency operation. Methods Many modern components allow voltage regulation to be controlled through ... are known as voltage mods in the overclocking community. Undervolting Undervolting is reducing the voltage of a component, usually the processor, reducing temperature and cooling requirements ..., V is the supply voltage , and f is the switching frequency, ref J. M. Rabaey. Digital Integrated ... with voltage. The formula is not exact however, as many modern chips are not implemented using 100 CMOS ... more details
Voltage and frequency scaling may refer to Dynamicvoltagescaling , a power management technique in computer architecture, where the voltage used in a component is increased or decreased, depending upon circumstances Dynamic frequency scaling , a technique in computer architecture whereby the frequency of a microprocessor can be automatically adjusted on the fly, either to conserve power or to reduce the amount of heat generated by the chip Voltage and frequency scaling are often used together to save power in mobile devices including cell phones. When used in this way it is commonly known as DVFS, or DynamicVoltage and Frequency Scaling. disambiguation ... more details
used when the workload is not CPU bound. Dynamic frequency scaling by itself is rarely worthwhile as a way to conserve switching power. Saving the most power requires dynamicvoltagescaling too, because ...for the CPU design principle Frequency scalingDynamic frequency scaling also known as CPU throttling ... of heat generated by the chip. Dynamic frequency scaling is commonly used in laptop s and other mobile ... 2008 04 21 ref Performance impact Dynamic frequency scaling reduces the number of instructions ... static, while dynamic frequency scaling is always dynamic. Software can often incorporate overclocked ... CPU technologies DEFAULTSORT Dynamic Frequency Scaling Category Power Architecture Category Clock ... ed systems. The dynamic power switching power dissipated by a chip is C V sup 2 sup f , where C is the capacitance being switched per clock cycle, V is voltage , and f is the switching frequency as a unitless ... changes, the dynamic power will change linearly with it. Dynamic power does not account for the total ... in 2008, dynamic power accounts for approximately two thirds of the total chip power, which limits the effectiveness of frequency scaling. citation needed date November 2008 Dynamicvoltagescaling is another power conservation technique that is often used in conjunction with frequency scaling, as the frequency that a chip may run at is related to the operating voltage. The efficiency of some electrical components, such as voltage regulators, decreases with increasing temperature, so the power ... in voltage or frequency may increase system power demands even further than the CMOS formula ... idle states. In most constant voltage cases it is more efficient to run briefly at peak speed and stay ... for a long time and only stay briefly in a light idle state. However, reducing voltage along with clock ... performance is increased by ramping the processor s dynamic frequency beyond the manufacturer ... is mostly done over the Front Side Bus mainly because the multiplier is normally locked , but dynamic ... more details
orphan date December 2008 DynamicVoltage Restoration DVR is a method and apparatus used to sustain, or restore, an operational electric load during sags, or spikes, in voltage supply. Often used in manufacturing areas requiring significant power to run tools equipment, and utility plants, this custom device mitigates potential damage to equipment and undesirable slowdowns to the production line caused by an abrupt change in electric load. This method uses critical devices such as an automatic Transfer switch and IGBT Modules in order to operate. External links http www.freepatentsonline.com 5883796.html Dynamic Series Voltage Restoration for Sensitive Loads in Unbalanced Power Systems Category Electric power distribution ... more details
wiktionarypar scalingScaling may refer to Scaling geometry , a linear transformation that enlarges or diminishes objects Reduced scales of semiconductor device fabrication processes the ability of a technology to scale to a smaller process Scalability , a computer s or network s ability to function as the number of users increases. Scaling, North Yorkshire , England Scaling law , a law that describes the scale invariance found in many natural phenomena Image scaling , the resizing of an image The scaling of critical exponents in physics, such as Widom scaling , or scaling of the renormalization group Scale invariance Fouling , i.e., formation of a deposit layer scale on a solid surface, e.g., in a boiler in particular, a kind of micro fouling as crystallization of salts Scaling and root planing , in dentistry, the removal of plaque, calculus, and stains 2.5D Scaling along the Z axis Scaling along the Z axis , a technique used in computer graphics for a pseudo 3D effect. Card throwing , known in magic circles as scaling. Scaling may also be used for Climbing Multidimensional scaling Scale disambig de Skalierung ... more details
about the scaling of electrical networks prototype filter frequency scaling the power conservation technique dynamic frequency scaling In computer architecture , frequency scaling also known as frequency ramping is the technique of ramping a processor s frequency so as to achieve performance gains. Frequency ramping was the dominant force in commodity processor performance increases from the mid 1980s until roughly the end of 2004. The effect of processor frequency on computer speed can be seen by looking at the equation for computer program runtime math Runtime frac Instructions Program times frac Cycles Instruction times frac Seconds Cycles math where instructions per program is the total instructions being executed in a given program, cycles per instruction is a program dependent, architecture dependent average value, and seconds per cycles is by definition the inverse of frequency. ref John L. Hennessy and David A. Patterson scientist David A. Patterson . Computer Architecture A Quantitative Approach. 3rd edition, 2002. Morgan Kaufmann, ISBN 1558607242. Page 43. ref An increase in frequency thus decreases runtime. However, power consumption in a chip is given by the equation math P C times V 2 times F math where P is power, C is the capacitance being switched per clock cycle, V is voltage , and F is the processor frequency cycles per second . ref J. M. Rabaey. Digital Integrated Circuits. Prentice Hall, 1996. ref Increases in frequency thus increase the amount of power used in a processor. Increasing processor power consumption led ultimately to Intel s May 2004 cancellation of its Tejas and Jayhawk processors, which is generally cited as the end of frequency scaling as the dominant .... With the end of frequency scaling, these new transistors which are no longer needed to facilitate frequency scaling can be used to add extra hardware, such as additional cores, to facilitate parallel computing a technique that is being referred to as parallel scaling . The end of frequency scaling ... more details
Unreferenced stub auto yes date December 2009 File 2D Random Walk 400x400.ogv thumb right 300px An animated example of a Brownian motion like random walk on a torus . In the scaling limit, random walk approaches the Wiener process according to Donsker s theorem . In physics or mathematics , the scaling limit is a term applied to the behaviour of a lattice model physics lattice model in the limit of the lattice spacing going to zero. A lattice model which approximates a Continuum theory continuum quantum field theory in the limit as the lattice spacing goes to zero corresponds to finding a second order phase transition of the model. This is the scaling limit of the model. It is often useful to use lattice models to approximate real world processes, such as Brownian motion . Indeed, according to Donsker s theorem , the discrete random walk would, in the scaling limit, approach the true Brownian motion . See also Universality classes DEFAULTSORT Scaling Limit Category Lattice models Category Renormalization group Category Critical phenomena Quantum stub ... more details
Refimprove date April 2008 In Euclidean geometry , uniform scaling or isotropic scaling , ref cite web ... diminishes objects by a scale factor that is the same in all directions. The result of uniform scaling ... ellipses. More general is scaling with a separate scale factor for each axis direction. Non uniform scaling anisotropic scaling is obtained when at least one of the scaling factors is different from the others a special case is directional scaling or stretching in one direction . Non uniform scaling ... if the sides of the square are not parallel to the scaling axes the angles between lines parallel ... uniform scaling is sometimes also called dilation or enlargement . When the scale factor is a positive number smaller than 1, scaling is sometimes also called contraction . In the most general sense, a scaling includes the case that the directions of scaling are not perpendicular. It includes also ... of one or more negative scale factors a directional scaling by 1 is equivalent to a Reflection mathematics reflection . Scaling is a linear transformation , and a special case of homothetic ... representation A scaling can be represented by a scaling matrix. To scale an object by a Vector ... , p sub z sub would need to be multiplied with this scaling matrix math S v begin bmatrix v x & 0 ... x p y p z end bmatrix begin bmatrix v xp x v yp y v zp z end bmatrix . math Such a scaling changes the diameter ... and the largest product of two scale factors, and the volume by the product of all three. The scaling is uniform if and only if the scaling factors are equal v sub x sub v sub y sub v sub z sub . If all except one of the scale factors are equal to 1, we have directional scaling. In the case where v sub x sub v sub y sub v sub z sub k , scaling increases the area of any surface by a factor of k ... of the other three components, a uniform scaling by a common factor s uniform scaling can be accomplished by using this scaling matrix math S v begin bmatrix 1 & 0 & 0 & 0 0 & 1 & 0 & 0 ... more details
Twin scaling is a method of plant propagation propagating plant bulb s that have a basal plate , such as Hippeastrum , Narcissus genus Narcissus , Galanthus and other members of the Amaryllidaceae some members of the lily family Liliaceae Lachenalia , Veltheimia and other members of the Hyacinthaceae . Purpose Twin scaling is practiced by professional growers and skilled amateurs to increase bulbs that would naturally propagate very slowly, or to speed up the production of desirable cultivar s. Using twin scaling it is possible to multiply one bulb into 16 to 32 or more viable bulbs in a couple of years, whereas natural propagation might only lead to a doubling every two years or so. It is one of a number of propagation techniques such as scooping , scoring and chipping based on the fact that an accidentally damaged bulb will often regenerate by forming small Bulb Bulbil bulblets or bulbil s on the damaged surface. Commercial growers have obtained as many as 100 twin scales from a single bulb. Method The dormant bulb which is to be twin scaled has its surface Sterilization microbiology Chemical sterilization sterilized by removing its dry tunic botany tunic and carefully trimming off its roots and any dead tissue, while leaving a layer of sound basal plate intact, then dipping the clean bulb in dilute bleach or another suitable disinfectant . The bulb is then sliced cleanly from top to bottom several times, creating 8 or 16 segments, depending on the size of the bulb. At this stage the segments are called chips many growers are content with simply chipping a bulb into 4 or 8 and do not divide the bulb further . True twin scaling involves further subdivision of the chips to create pairs of scales, joined together by a small part of the basal plate. The twin scales are then treated ... Twin scaling a step by step guide with Abbie and Mark Jury illustration of the twin scaling technique Category Horticulture and gardening horticulture stub de Twin scaling ... more details
Please leave this line alone Feature scaling is a method used to standardize the range of independent variables or features of data. In data processing , it is also known as data normalization and is generally performed during the data preprocessing step. Motivation Since the range of values of raw data varies widely, in some machine learning algorithms, objective functions will not work properly without normalization. For example, the majority of classifiers calculate the distance between two points by the distance. If one of the features has a broad range of values, the distance will be governed by this particular feature. Therefore, the range of all features should be normalized so that each feature contributes approximately proportionately to the final distance. Deleted image removed Image Before FS.png thumb 300px A convergence of the Gradient Descent algorithm before applying feature scaling Deleted image removed Image After FS.png thumb 300px A convergence of the Gradient Descent algorithm after applying feature scaling Methods Rescaling The simplest method is rescaling the range of features to make the features independent of each other and aims to scale the range in 0, 1 or 1, 1 . Selecting the target range depends on the nature of the data. The general formula is given as math x frac x min max min math where math x math is an original value, math x math is the normalized ... scaling can improve the convergence speed of the algorithm. In SVM ref cite journal last Juszczak first P. coauthors D. M. J. Tax, and R. P. W. Dui date 2002 title Feature scaling in support vector ... Wang, and Licheng Jiao, Feature Scaling for Kernel Fisher Discriminant Analysis Using Leave one out ... xpl freeabs all.jsp?arnumber 4517925 E. Youn, M. K. Jeong , Class dependent feature scaling method ... 100 Lecture by Andrew Ng on feature scaling http www.statalgo.com 2011 10 17 stanford ml 1 2 gradient descent Gradient Descent using feature scaling http mipa.med.upatras.gr educational 20resources ... more details
Refimprove date December 2009 Binary scaling is a computer programming technique used mainly by embedded C programming language C , Digital signal processing DSP and assembly language assembler programmers to perform a pseudo floating point using integer arithmetic. It is both faster and more accurate than directly using floating point instructions, however care must be taken not to cause an arithmetic overflow . A position for the virtual binary point is taken, and then subsequent arithmetic operations determine the resultants binary point . Binary points obey the mathematical laws of exponentiation ... 6.71999. The correct floating point result is 6.72. The scaling range here is for any number between ... the binary scale can be adjusted for optimum accuracy. Re scaling after multiplication The example above for a B16 multiplication is a simplified example. Re scaling depends on both the B scale ... scalings the complete B scaling formula must be used. Consider a 32 bit word size, and two variables, one with a B scaling of 2 and the other with a scaling of 4. 1.4 B2 is 1.4 2 sup wordsize 2 1 sup ... scaling is always more accurate than floating point of the same word size. This is especially useful ... thumb Binary scaling B0 Representation of angles. span style color black Black span is traditional ... patterns that are not valid angles at all NaN , or both. Application of binary scaling techniques Binary scaling techniques were used in the 1970s and 80s for real time computing that was mathematically ... results of equations. Binary scaling is still used in many digital Signal Processing DSP applications and custom made microprocessors are usually based on binary scaling techniques. Binary scaling is currently used in the Discrete cosine transform DCT used to compress JPEG images in utilities ... accuracy are required, binary scaling works on simpler hardware and is more accurate when the range ... Binary Scaling Category Binary arithmetic Scaling ... more details
Widom scaling is a hypothesis in statistical mechanics regarding the Thermodynamic free energy free energy of a magnetic system near its critical point thermodynamics critical point which leads to the critical exponent s becoming no longer independent so that they can be parameterized in terms of two values. The hypothesis can be seen to arise as a natural consequence of the block spin renormalization procedure, when the block size is chosen to be of the same size as the correlation length. ref Kerson Huang, Statistical Mechanics. John Wiley and Sons, 1987 ref Widom scaling is an example of universality dynamical systems universality . Definitions The critical exponents math alpha, alpha , beta, gamma, gamma math and math delta math are defined in terms of the behaviour of the order parameters and response functions near the critical point as follows math M t,0 simeq t beta math , for math t uparrow 0 math math M 0,H simeq H 1 delta mathrm sign H math , for math H rightarrow 0 math math chi T t,0 simeq begin cases t gamma , & textrm for t downarrow 0 t gamma , & textrm for t uparrow 0 end cases math math c H t,0 simeq begin cases t alpha & textrm for t downarrow 0 t alpha & textrm for t uparrow 0 end cases math where math t equiv frac T T c T c math measures the temperature relative to the critical point. Derivation The scaling hypothesis is that near the critical point, the free energy math f t,H math , in math d math dimensions, can be written as the sum of a slowly varying regular part math f r math and a singular part math f s math , with the singular part being a scaling ..., putting math t 0 math and math lambda H 1 q math into the scaling relation for M yields math delta ... of M to the scaling relation yields math lambda 2q chi T lambda p t, lambda q H lambda d chi T t, H ... for specific heat math c H math in terms of M to the scaling relation yields math lambda 2p c H lambda ... As a consequence of Widom scaling, not all critical exponents are independent but they can be parameterized ... more details
Multidimensional scaling MDS is a set of related statistical techniques often used in information visualization for exploring similarities or dissimilarities in data. MDS is a special case of Ordination statistics ordination . An MDS algorithm starts with a matrix mathematics matrix of item item Similarity ... matrix Classical multidimensional scaling Also known as Torgerson Scaling or Torgerson Gower scaling, takes an input matrix giving dissimilarities between pairs of items and outputs a coordinate ... Borg, I., Groenen, P. title Modern Multidimensional Scaling theory and applications publisher Springer ... scaling A superset of classical MDS that generalizes the optimization procedure to a variety ... majorization . Non metric multidimensional scaling In contrast to metric MDS, non metric MDS finds ... SSA is an example of a non metric MDS procedure. Generalized multidimensional scaling An extension of metric multidimensional scaling, in which the target space is an arbitrary smooth non Euclidean ... bron cite journal author Bronstein AM, Bronstein MM, Kimmel R title Generalized multidimensional scaling ... function. ref name Kruskal Joseph Kruskal Kruskal, J. B. , and Wish, M. 1978 , Multidimensional Scaling ... is considered good for metric scaling and .9 is considered good for non metric scaling. Other ... Marketing Generalized multidimensional scaling GMDS Data clustering Factor analysis Discriminant ... author Cox, T.F., Cox, M.A.A. title Multidimensional Scaling publisher Chapman and Hall year 2001 cite book author Coxon, Anthony P.M. title The User s Guide to Multidimensional Scaling. With special ..., W.S. title Theory & Methods of Scaling publisher Wiley location New York year 1958 isbn 0898747228 ... to multidimensional scaling http www.newmdsx.com NewMDSX Multidimensional Scaling Software http ... Multidimensional Scaling Category Multivariate statistics Category Market research Category Psychometrics ... it Scaling multidimensionale ja pl Skalowanie wielowymiarowe zh ... more details
File 2xsai example.png frame An image scaled with nearest neighbor scaling left and 2 SaI scaling right . In computer graphics, image scaling is the process of resizing a digital image . Scaling is a non trivial process that involves a trade off between efficiency, smoothness and sharpness. As the size of an image is increased, so the pixel s which comprise the image become increasingly visible, making the image appear soft . Conversely, reducing an image will tend to enhance its smoothness and apparent ... of the original pixels. Scaling methods An image size can be changed in several ways. Consider ..., now show the characteristic stairway shape. Other scaling methods are better at preserving ... softening of details and can still be somewhat jagged. Better scaling methods include bicubic ... results will be achieved by hqx or other pixel art scaling algorithms . These produce sharp edges and maintain high level of detail. hq2x File Image after hq2x.png For scaling photos and raster images ... scaling algorithms are bilinear filtering bilinear and bicubic interpolation . Filters like these work ... the sharpness of horizontal and vertical lines and smooth all other curves. Pixel art scaling algorithms Split section Pixel art scaling algorithms date January 2012 Efficiency Since a typical application ... all 4 to the colour of the in pixel we are currently scaling as nearest neighbor . Next look at the pixels ... ZSNES and VisualBoyAdvance , offer this scaling algorithm as a feature. Since Kreed released ref http .... Several slightly different versions of the scaling algorithm are available, and these are often ... RotSprite is a scaling and rotation algorithm for sprites developed by Xenowhirl. It produces ... with a nearest neighbor scaling and rotation algorithm that simultaneously shrinks the big image ..., crisp graphics while minimizing blur. Scaling art algorithms have been implemented in a wide range ... 01.htm Interpolation by Vincent Bockaert http www.leptonica.com scaling.html General Scaling ... more details
In neuroscience, synaptic scaling is a form of homeostatic plasticity homeostatic plasticity that allows single neuron neurons to regulate their overall action potential firing rate. Like many other physiological systems, neural electrochemical activity is subject to homeostasis homeostasis . Where Hebbian Plasticity mechanisms modify neural synaptic connections selectively, synaptic scaling works in unison with other homeostatic plasticity mechanisms to normalize all neural synaptic connections ref Turrigiano, Gina 2000 ref . Cellular components involved in synaptic scaling Chemical synapse Chemical Synaptic connection At chemical synapses, pre synaptic neurons release vesicles containing neurotransmitters ... , or potassium br Interactions of cellular components involved in Synaptic Scaling Synaptic scaling ... homeostatic plasticity regulation systems. In synaptic scaling, neurons use this information to determine a scale factor. Each neuron subsequently uses the scaling factor to globally scale either ... the quantity of post synaptic AMPA receptors over short time periods. br Global synaptic scaling This form ... migrate to the post synaptic cleft from the entire cell. br Synaptic Scaling Mechanisms Local ... receptor scaling mechanisms by imaging post synaptic trans membrane GluR2 GluR2 subunits using pharmaceutical ... by local mRNA transcription. br Global Synaptic Scaling This form of synaptic scaling takes ... Properties of Synaptic Scaling Another study by Dr.Turrigiano ref Wierga, 2006 ref looked at homeostatic ... scaling older cultures 18 days in vitro use a combination of both pre synaptic and post synaptic ... application of TTX. This form of pre synaptic homeostatic plasticity and synaptic scaling a form of post ... synaptic scaling of excitatory synapses. Cell, 135 3 , 422 435. DOI 10.1016 j.cell. 2008. 10.008 ... scaling induced by changes in post synaptic firing . Neuron, 57 6 , 819 826. DOI 10.1016 j. neuron ... ,W. 2004 . A morphological correlate of synaptic scaling in visual cortex . Journal of Neuroscience ... more details
Power scaling of a laser is increasing its output power without changing the geometry, shape, or principle of operation. Power scalability is considered an important advantage in a laser design. Usually, power scaling requires a more powerful laser pumping pump source, stronger cooling, and an increase in size. It may also require reduction of the background loss in the optical resonator laser resonator and, in particular, in the gain medium . MOPA The most popular way of achieving power scalability is the MOPA Master Oscillator Power Amplifier approach. The master oscillator produces a highly coherent beam, and an optical amplifier is used to increase the power of the beam while preserving its main properties. The master oscillator has no need to be powerful, and has no need to operate at high efficiency because the efficiency is determined mainly by the power amplifier. The combination ... One type of solid state laser designed for good power scaling is the disk laser or active mirror ref ... Results and scaling laws of thin disk lasers journal Proceedings of SPIE volume 5332 pages 212 227 year ... Surface loss limit of the power scaling of a thin disk laser journal JOSAB volume 23 issue 6 pages ... JOSAB.23.001074 bibcode 2006JOSAB..23.1074K ref For future power scaling, the reduction of the round ... type of solid state laser with good power scaling. The power scaling of fiber lasers is limited ... of the shape of the cladding can extend the limit of power scaling. ref name KouznetsovHighly cite ... The limit of power scaling of fiber lasers can be extended with lateral delivery of the pump. This is realized ... format PDF author K. Ueda title Scaling physics of disk type fiber lasers for kW output journal Lasers ... The power scaling is limited by the ability to dissipate the heat. Usually, the thermal conductivity ... scaling. Coherent addition and combining beams Image CoherentAddition.jpg 200px thumb right Coherent ... has been reported. Further power scaling requires exponential growth of the Gain bandwidth product gain ... more details
A 3D scaling storage architecture provides the ability to Scalability Scale vertically scale up scale up ref cite web url http www.enterprisestrategygroup.com 2010 05 scale up storage title Scale up Storage publisher Enterprise Strategy Group accessdate 2010 11 23 ref for improved performance, Scalability Scale horizontally scale out scale out ref cite web url http www.enterprisestrategygroup.com 2010 06 scale out storage title Scale out Storage publisher Enterprise Strategy Group accessdate 2010 11 23 archiveurl http web.archive.org web 20101225091335 http www.enterprisestrategygroup.com 2010 06 scale out storage archivedate 25 December 2010 DASHBot deadurl no ref to improve capacity and deliver increased aggregate throughput and scale deep to connect and manage external multi vendor storage platforms. This architecture is derived from the Super Computing world ref cite web url http wwwjp.cray.com downloads Tabor XT5 Whitepaper.pdf title Designed to Scale The Cray XT5 Family of Supercomputers publisher Tabor Research accessdate 2010 11 04 ref using a design that includes specialized elements within the system allowing for an increase in overall system performance and efficiency. A storage system built on a 3D architecture is designed primarily for use with enterprise storage applications. As the number of virtualized servers hosted on a physical server grows, due to the increased processing capability of servers with multi core processors and increased memory, the I O workload of these virtual servers tends to be consolidated onto a single storage system. These storage systems ... common pool of resources. Scale Up Scaling up ref cite web url http www.storage switzerland.com Articles ... core and special purpose processors to handle critical internal functions. Scaling Up can be handled ... computing characteristics. Scaling out can deliver the ability to improve both performance ... host server access to required storage resources from a common pool. Scale Deep Scaling deep ... more details
, electron and ion densities x sup 2 sup This scaling applies best to plasmas with a relatively low ... inversely with the size. This is also the scaling required by Faraday s law of induction and Amp re .... Furthermore, in regions where quasineutrality is violated, this scaling is required by Gauss s law ... the scaling in terms of nondimensional parameters. Geometrical parameters, such as the ratio of the major ... sup , and B R sup 1 sup . This is because the physical effects to be studied are different. The scaling ... R by varying the magnetic field and scaling density and temperature as n B sup 4 3 sup T B sup 2 ... more details
Refimprove date September 2010 File 7812 voltage regulator.jpg thumb right A popular three pin 12 V DC voltage regulator IC. A voltage regulator is an electricity electrical regulator automatic control regulator designed to automatically maintain a constant voltage level. A voltage regulator may be a simple .... Electronic voltage regulators are found in devices such as computer power supply power supplies where ... s and central power station generator plants, voltage regulators control the output of the plant. In an electric power distribution system, voltage regulators may be installed at a substation or along distribution lines so that all customers receive steady voltage independent of how much power is drawn from the line. Measures of regulator quality The output voltage can only be held roughly constant the regulation is specified by two measurements load regulation is the change in output voltage for a given ... 5mA and 1.4A, at some specified temperature and input voltage . line regulation or input regulation is the degree to which output voltage changes with input supply voltage changes as a ratio of output to input change for example typically 13mV V , or the output voltage change over the entire specified input voltage range for example plus or minus 2 for input voltages between 90V and 260V, 50 60Hz . Other important parameters are Temperature coefficient of the output voltage is the change in output voltage with temperature perhaps averaged over a given temperature range , while... Initial accuracy of a voltage regulator or simply the voltage accuracy reflects the error in output voltage for a fixed ... voltage is the minimum difference between input voltage and output voltage for which the regulator ... to work well even with an input supply only a Volt or so above the output voltage. The input output differential at which the voltage regulator will no longer maintain regulation is the dropout voltage. Further reduction in input voltage will result in reduced output voltage. This value is dependent ... more details
for formation of inversion channel electron density and attainment of threshold voltage IV in a nanowire MOSFET. Note that the threshold voltage for this device lies around 0.45V. The threshold voltage , commonly abbreviated as Vth , of a MOSFET is usually defined as the gate voltage where an Inversion ... has positively charged mobile holes as carriers. When a positive voltage is applied on the gate, an electric ... immobile negatively charged acceptor ions. A further increase in the gate voltage eventually causes ... the gate voltage at which the electron density at the interface is the same as the hole density in the neutral bulk material is called the threshold voltage. Practically speaking the threshold voltage is the voltage at which there are sufficient electrons in the inversion layer to make a low ... the bulk charge neutral. If the gate voltage is below the threshold voltage top figure , the transistor ... current, although it is small and varies exponentially with gate bias. If the gate voltage is above the threshold voltage lower figure , the transistor is turned on, due to there being many electrons ... inversion. The channel is tapered when V sub D sub 0 because the voltage drop due to the current in the resistive ... devices the threshold voltage is a much less clear cut parameter subject to variation with the biases ... describes the changes in the threshold voltage by the change in math V SB math , the source bulk voltage. Since the body influences the threshold voltage when it is not tied to the source , it can ... mode, n mos MOSFET body effect upon threshold voltage is computed according to the Shichman ... V SB 2 phi F sqrt 2 phi F math where math V TN math is the threshold voltage when substrate bias ..., and math V TO math is threshold voltage for zero substrate bias, math gamma t ox epsilon ox ... In a given technology node, such as the 90 nanometer CMOS process, threshold voltage depends on the choice ..., the thinner the oxide thickness, the lower the threshold voltage. While this may seem to be an improvement ... more details
In graph theory graph theoretic mathematics , a voltage graph is a directed graph whose edges are labelled ... graph called the derived graph of the voltage graph. Typical choices of the groups used for voltage ... > 2. When &Pi is a cyclic group, the voltage graph may be called a cyclic voltage graph . Definition Formal definition of a span class texhtml span voltage graph, for a given group span class ... in notation. A span class texhtml span voltage on an arc of G is a label of the arc by an element ... n sub span , the label is a number i mod n . A span class texhtml span voltage assignment is a function math alpha E G rightarrow Pi math that labels each arc of G with a voltage. A span class texhtml span voltage graph is a pair math G, alpha E G rightarrow Pi math such that G is a digraph and &alpha is a voltage assignment. The voltage group of a voltage graph math G, alpha .... Note that the voltages of a voltage graph need not satisfy Kirchhoff s circuit laws Kirchhoff s voltage law KVL Kirchhoff s voltage law , that the sum of voltages around a closed path is 0 the identity ... may be somewhat misleading. It results from the origin of voltage graphs as dual to the current graph s of topological graph theory . The derived graph The derived graph of a voltage graph math ... e math . Although voltage graphs are defined for digraphs, they may be extended to undirected graph ... graph is a covering graph of the given voltage graph. If no edge label of the voltage graph is the identity ... special case is the bipartite double cover , the derived graph of a voltage graph in which ... voltage graph contains any directed cycles. ref name periodic Examples Any Cayley graph of a group &Pi , with a given set &Gamma of generators, may be defined as the derived graph for a &Pi voltage graph ... 5 sub voltage graph in the shape of a dumbbell with two vertices and three edges one edge connecting ... polynomial time and NC algorithms for detecting cycles in dynamic graphs doi 10.1145 73007.73057 ... more details
wikitionary VoltageVoltage abbreviated V is the term for the difference in electric potential energy. It may also refer to Electrical Engineering Voltage divider , a circuit that produces an output voltage that is a fraction of its input Voltage reference , an electronic device that produces a constant voltageVoltage regulator , an electronic device designed to maintain a constant voltageVoltage source , a circuit theory term, the dual of a current source. Voltage spike , an electrical engineering term for sudden changes in voltageVoltage controlled filter VCF , a type of electronic filter Voltage controlled amplifier VCA , a type of electronic amplifier Places Voltage , an unincorporated community in Harney County, Oregon, United States See also Volt disambiguation Ampere disambiguation disambiguation NOTOC ... more details
is overclocking overclocked the processor increases the core voltage at the cost of system stability, power consumption and heat dissipation. This is known as Dynamicvoltagescaling overvolting ... http www.tomshardware.com 2003 12 30 5 ghz project Extreme overvolting ref See also Dynamicvoltagescaling References reflist External links http www.hardwareanalysis.com content article 1482 Hardwareanalysis.com s article about how to increase voltage to help overclocking Category Central processing ...The CPU core voltage V sub CORE sub is the power supply voltage supplied to the central processing unit CPU which is a digital circuit , Graphics processing unit GPU , or other device containing a processing core. The amount of Power physics power a CPU uses, and thus the amount of heat it dissipates, is the product of this voltage and the Current electricity current it draws. In modern CPUs, which are made using CMOS , the current is almost proportional to the Clock rate clock speed , the CPU drawing almost no current between clock cycles. See, however, subthreshold leakage . In order to help conserve power and manage heat, many laptop and desktop computer desktop processors have a power management feature that allows software usually the operating system to dynamic frequency scaling adjust the clock speed and dynamicvoltagescaling core voltage dynamically . The trend is towards lower ... the voltages go only to ground and the supply voltage, the source, gate, and drain terminals of the Field effect transistor FETs have only the supply voltage or zero voltage across them. The MOSFET ... is proportional to the gate source voltage reduced by a Threshold Voltage threshold voltage math ... to reduce the supply voltage and to increase current one must increase capacitance. But, the load being ..., which thus requires the designer to keep it low. The trend towards lower supply voltage therefore ... voltage allow both to improve at once. On another note, the formula shown above is for long ... more details
Refimprove date December 2009 In electrical engineering , particularly power engineering , voltage regulation is the ability of a system to provide near constant voltage over a wide range of Electrical load load conditions. Electrical power systems In electrical power systems it is a dimensionless quantity defined at the receiving end of a transmission line as math Voltage Regulation VR frac V nl V Rated V Rated times 100 math ref cite book last Chapman first Stephen J. title Electric Machinery Fundamentals year 2005 publisher McGraw Hill isbn 978 0 07 246523 5 pages 100, 263. ref where V sub nl sub is voltage at no load and V sub Rated sub is voltage at full load. A smaller value of VR is usually beneficial. The Voltage Regulation formula could be visualized with the following Consider power being delivered to a load such that the voltage at the load is the load s rated voltage V sub Rated sub , if then the load disappears, the voltage at the point of the load will rise to V sub nl sub . Electronic power supply parameters The quality of a system s voltage regulation is described by three main parameters class wikitable border 1 Parameter S sub T sub Measure of the ability to maintain a constant output voltage, regardless of variations in temperature of electrical components within the system, especially semiconductor based devices. Sometimes, the term voltage regulation is used to describe processes by which the quantity VR is reduced, especially concerning special circuits and devices for this purpose, voltage regulators . Voltage regulators are an important part of power ... point the point at which the equipment tries to maintain constant voltage. Customers further than this point observe an expected effect higher voltage at light load, and lower voltage at high load. Customers closer than this point experience the opposite effect higher voltage at high load, and lower voltage at light load. References Reflist See also Voltage regulator DEFAULTSORT Voltage Regulation ... more details
File Voltage portal.jpg thumb Cut away view of a voltage portal A Voltage portal extends a voltage source to the outside of an Enclosure electrical electrical enclosure in an encapsulated non conductive housing designed for a Non contact voltage detector NCVD to sense voltage if placed into the voltage portal. Overview A voltage portal avoids voltage exposure for workers by extending the voltage source points to the outside of electrical enclosures. Each voltage point resides in an encapsulated non conductive housing designed to insure that a NCVD senses voltage if placed into the voltage portal Fig. 1 . Because a voltage portal contains Live wire electricity live voltage and mounts on the outside of an electrical enclosure, it must be robust to insure long term safety. The Underwriters Laboratories UL enclosure type rating of the voltage portal must also match the enclosure rating. Maintenance work Many maintenance workers carry NCVD pens or AC voltage detector s in their tool belts. This portable device allows workers to quickly check electrical conductors for live voltage without actually touching the bare wire. The NCVD can sense voltage when positioned close to the live conductor without making a hard wired electrical connection. A voltage portal is used to assist workers in creating an electrically safe work condition as part of a lockout tagout procedure before beginning work on electrical or mechanical equipment. References Reflist External links http graceport.com assets files Application 20Notes Application VoltagePortals 20Improve 20NCVD.pdf http www.mt online.com component content article 295 june2011 1794 electrical safety sense better voltage detection.html Categories Category Articles created via the Article Wizard Category Electrical components Category Electrical safety ... more details
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