In atmospheric sciences meteorology , climatology and related fields , the pressuregradient typically ... direction and at what rate the pressure changes the most rapidly around a particular location. The pressuregradient is a dimensional quantity expressed in Units of measurement units of pressure ... coordinate system coordinates of the location of interest, then the pressuregradient ... Strictly speaking, the concept of pressuregradient is a local characterization of the air more generally of the fluid under investigation . The pressuregradient is defined only at those spatial scales at which pressure more generally fluid dynamics itself is defined. Within planet ary atmosphere s including the Earth s atmosphere Earth s , the pressuregradient is a vector pointing roughly downwards, because the pressure changes most rapidly vertically, increasing downwards. The value of the strength or Norm mathematics norm of the pressuregradient in the troposphere is typically of the order 9 Pa m or 90 hPa km . The pressuregradient often has a small but critical horizontal component, which is largely responsible for the wind circulation. The horizontal pressuregradient is a 2 dimensional vector resulting from the projection of the pressuregradient onto a local horizontal plane. Near the Earth s surface , this horizontal pressuregradient is typically pointing towards high pressure ... on the weather situation. At mid latitude s, the typical horizontal pressuregradient may take on values ..., the pressuregradient constitutes one of the main forces acting on the air to make it move as wind. Note that the pressuregradient force points from high towards low pressure zones, it is thus oriented in the opposite direction from the pressuregradient itself. Sound waves and shock wave s are events ... simple Pressuregradient uk ... description Assuming that the pressure p is an intensive quantity , i.e., a single valued ... more details
Multiple issues unreferenced February 2010 wikify February 2011 orphan January 2011 Pore pressuregradient is a dimensional Petrophysics petrophysical term used by drilling engineer s during the design of drilling programs for drilling constructing Oil well oil and gas wells into the earth. It is the pressuregradient inside the pore space of the rock column from the surface of the ground down to total depth TD , as compared to the pressuregradient of seawater in deep water. Whereas in pure math , the gradient of a scalar function expressed by the math notation grad f may not have physical units associated with it in drilling engineering the pore pressuregradient is usually expressed in API type International Association of Drilling Contractors IADC physical units of measurement, namely psi per foot. In the well known formula P 0.052 mud weight total vertical depth taught in almost all petroleum engineering courses worldwide, the mud weight MW is expressed in pounds per U.S. gallon, and the total vertical depth TVD is expressed in feet, and 0.052 is a conversion constant that can be derived by dimensional analysis later. This is pretty lazy considering math mathrm 1 psi ft frac 1 ... wellbore from top to bottom vertical hole , the pressuregradient would be grad P pressuregradient 0.052 8.33 0.433 psi ft and the hydrostatic bottom hole pressure BHP is then BHP grad P TVD 0.43316 41,000 17,759 psi However, the pore pressure is usually much greater than a column of fresh water ... open hole interval at 41,000 feet with a pore pressuregradient of 19 lb U.S. gal, the BHP ... ref ref tags which will then appear here automatically Reflist DEFAULTSORT Pore PressureGradient Category ... well blowouts. Simple Examples Using the figures above, we can calculate the maximum pressure ... pressure in the rock could be as high as 1.0 psi ft of depth 19 .052 A well with 5,000 feet of seawater ... 1.0 . That pressure is reduced at the surface by the weight of oil and gas the riser pipe, but this is only ... more details
The pressuregradient force is not actually a force but the acceleration of air due to pressure difference a force per unit mass . It is usually responsible for accelerating a parcel of air from a high atmospheric pressure region to a low pressure region, resulting in wind . In meteorology, pressuregradient force refers to the horizontal movement of air according to the equation math frac F x m frac 1 rho frac dp dx frac F y m frac 1 rho frac dp dy frac F z m frac 1 rho frac dp dz math The term math F m math is equal to the acceleration math dv dt math because this is an expression of Newton s law math F ma math . math dp dx math is the component of the pressuregradient along the x axis. math rho math is the mass density and math 1 rho math shows that as the mass density increases, the acceleration due to the pressuregradient becomes smaller. The pressuregradient force acts at right angles to isobar meteorology isobar s in the direction from high to low pressure. The greater the pressure difference over a given horizontal distance, the greater the force and hence the stronger the wind. The pressuregradient force, however, is not the only force that acts on a moving parcel of air &mdash if it were, then low and high pressure regions would eventually disappear. Other forces acting on a horizontally moving parcel of air include surface friction , coriolis force , centrifugal force fictitious centrifugal force . In large scale atmospheric flows, the coriolis force generally balances the pressuregradient force, producing winds blowing largely along the isobars however, near the surface the friction term is also important, generally giving a resulting net wind direction diagonal to the isobars with a component blowing towards the low pressure center . References Roland B. Stull 2000 Meteorology for Scientists and Engineers , Second Edition, Ed. Brooks Cole, ISBN 0 534 37214 7. Category Fluid dynamics Category Atmospheric dynamics climate stub ca For a b rica de Gradientkraft ... more details
Unreferenced date March 2009 An adverse pressuregradient occurs when the static pressure increases in the direction of the flow. Mathematically this is expressed as math dP dx 0 math . This is important for boundary layer s, since increasing the fluid pressure is akin to increasing the potential energy of the fluid, leading to a reduced kinetic energy and a deceleration of the fluid . Since the fluid in the inner part of the boundary layer is relatively slower, it is more greatly affected by the increasing pressuregradient. For a large enough pressure increase, this fluid may slow to zero velocity or even become reversed. When flow reversal occurs, the flow is said to be separated from the surface. This has very significant consequences in aerodynamics since flow separation significantly modifies the pressure distribution along the surface and hence the Lift force lift and Drag physics drag characteristics. Turbulent boundary layers tend to be able to sustain an adverse pressuregradient better than an equivalent laminar flow laminar boundary layer. The more efficient mixing which occurs in a turbulent boundary layer transports kinetic energy from the edge of the boundary layer to the low momentum flow at the solid surface, often preventing the separation which would occur for a laminar boundary layer under the same conditions. This physical fact has led to a variety of schemes to actually produce turbulent boundary layers when boundary layer separation is dominant at high Reynolds number s. The dimples on a golf ball, the fuzz on a tennis ball, or the seams on a baseball are good examples. Aeroplane wing s are often engineered with vortex generator s on the upper surface to produce a turbulent boundary layer. Category Fluid dynamics fluiddynamics stub ... more details
of steepness of a line Slope other uses In vector calculus , the gradient of a scalar field is a vector ... magnitude mathematics magnitude is that rate of increase. A generalization of the gradient ... corresponding gradient is represented by blue arrows. Interpretations File Gradient of a Function.tif thumb 350px Gradient of the 2 d function math f x,y xe x 2 y 2 math is plotted as blue arrows over ... time. At each point in the room, the gradient of math T math at that point will show the direction the temperature rises most quickly. The magnitude of the gradient will determine how fast the temperature ..., y math is math H x, y math . The gradient of math H math at a point is a vector pointing in the direction ... is given by the magnitude of the gradient vector. The gradient can also be used to measure how ... as follows. If the hill height function math H math is differentiable function differentiable , then the gradient ..., the dot product of the gradient of math H math with a given unit vector is equal to the directional ... 350px The gradient of the function f x , y &minus cos sup 2 sup x cos sup 2 sup y sup 2 sup depicted as a projected vector field on the bottom plane The gradient or gradient ... , del . The notation math operatorname grad f math is also commonly used for the gradient. The gradient ... v f x . math In a rectangular coordinate system, the gradient is the vector field whose components ... directions. When a function also depends on a parameter such as time, the gradient often ... unit vectors. For example, the gradient of the function math f x,y,z 2x 3y 2 sin z math ... to represent the gradient as a row vector or column vector of its components in a rectangular coordinate system. Gradient and the derivative or differential Linear approximation to a function The gradient ... nabla f x 0 cdot x x 0 math for math x math close to math x 0 math , where math nabla f x 0 math is the gradient ... of math f math at math x math . The gradient is therefore related to the differential by the formula ... more details
Wiktionarypar gradient The Gradient is the rate of variation of a numerical quantity. It may refer to Slope or Grade slope grade , referring to the inclination of a road or other geographic features Image gradient , a gradual change or blending of color Color gradient Texture gradient Mathematics Gradient , in vector calculus, a vector field representing the maximum rate of increase of a scalar field or a multivariate function and the direction of this maximal rate. Gradient descent Gradient theorem Gradient method Conjugate gradient method Nonlinear conjugate gradient method Stochastic gradient descent Biology diffusion Concentration gradient , the ratio of solute concentration between two adjoining regions Potential gradient , the difference in electric charge between two adjoining regions Fluid dynamics and earth science Density gradientPressuregradient Temperature gradient Geothermal gradient Sound speed gradient Wind gradient See also lookfrom gradient intitle gradient Graduation disambiguation Fade disambiguation disambig bs Gradijent vor cs Gradient de Gradient eo Gradiento io Gradiento homonimo ja pl Gradient simple Gradient disambiguation tl Gradient ... more details
easily and quickly. This is one example of a practical application of pressure. The gradient ...about pressure in the physical sciences Image Pressure exerted by collisions.svg thumb right 250px alt A figure showing pressure exerted by particle collisions inside a closed container. The collisions that exert the pressure are highlighted in red. Pressure as exerted by particle collisions inside a closed container. Thermodynamics cTopic List of thermodynamic properties System properties Pressure ... of an object. Gauge pressure also spelled gage pressure ref group lower alpha The preferred spelling ... spelling. Many of the largest American manufacturers of pressure transducers and instrumentation use the spelling gage pressure in their most formal documentation Honeywell Sensotec s http www.sensotec.com ... 22gage pressure 22&x 0&y 0 product search page . ref is the pressure relative to the local atmospheric or ambient pressure. Definition Pressure is the effect of a force applied to a surface. Pressure is the amount of force acting per unit area. The symbol of pressure is p . ref group lower ... math p frac F A mbox or p frac dF n dA math where p is the pressure, F is the normal force , A is the area of the surface area on contact Pressure is a Scalar physics scalar quantity. It relates the vector surface element a vector normal to the surface with the normal force acting on it. The pressure ... usual to say the pressure is directed in such or such direction . The pressure, as a scalar, has ..., not the pressure. If we change the orientation of the surface element, the direction of the normal force changes accordingly, but the pressure remains the same. Pressure is transmitted to solid boundaries ... column The SI unit for pressure is the Pascal unit pascal Pa , equal to one newton unit newton per ... 27 ref before that, pressure in SI was expressed simply as N m sup 2 sup . Non SI measures such as pound ..., primarily in the United States of America. The cgs unit of pressure is the barye ba , equal to 1 ... more details
Infobox Album See Wikipedia WikiProject Albums Name The Pressure Is On Type studio Artist Hank Williams, Jr. Cover ThePressureIsOn.jpg Released start date 1981 08 Recorded Genre Country music Country Length 33 59 Label Elektra Records Elektra Curb Records Curb Producer Jimmy Bowen Last album Rowdy Hank Williams, Jr. album Rowdy br 1981 This album The Pressure Is On br 1981 Next album High Notes br 1982 Album ratings rev1 Allmusic rev1Score Rating 4 5 ref name allmusic cite web last Jurek first Thom title The Pressure Is On review url Allmusic class album id the pressure is on r94746 pure url yes work Allmusic accessdate 16 February 2011 ref The Pressure Is On is a studio album by American country music artist Hank Williams, Jr. . It was released by Elektra Records Elektra Curb Records in August 1981. All My Rowdy Friends Have Settled Down and A Country Boy Can Survive were released as singles. The album peaked at number 5 on the Billboard magazine Billboard Top Country Albums chart ref cite web title The Pressure Is On Charts url Allmusic class album id the pressure is on r94746 charts awards pure url yes work Allmusic accessdate 16 February 2011 ref and has been certified Platinum by the Recording Industry Association of America RIAA . ref http www.riaa.org goldandplatinumdata.php?resultpage 1&table SEARCH RESULTS&action &title pressure 20is 20on&artist &format &debutLP &category &sex &releaseDate &requestNo &type &level &label &company &certificationDate &awardDescription &catalogNo &aSex &rec id &charField &gold &platinum &multiPlat &level2 &certDate &album &id &after &before &startMonth 1&endMonth 1&startYear 1958&endYear 2011&sort Artist&perPage 25 RIAA Gold & Platinum ref Track listing A Country Boy Can Survive Hank Williams, Jr. 4 16 The Coalition to Ban Coalitions ... Emerson , Vince Emerson 3 13 The Pressure Is On Williams, Jr. 4 13 All My Rowdy Friends Have Settled ... 5 U.S. Billboard 200 align center 76 References reflist DEFAULTSORT Pressure Is On Category 1981 ... more details
was deleted Image Pressure cd.jpg thumb Things Move Fast 1999 My Heart Was Lost , cassette, Self Service Recs, 1997. The Pressure , cassette, Corporate Corp Recs, 1997. I Wanna Call Someone , 7 single ... Pressure, The Category American post punk music groups Category American post hardcore musical ... more details
About the album the 2010 short film No Pressure film the episode from the TV series How I Met Your Mother No Pressure How I Met Your Mother Infobox album See Wikipedia WikiProject Albums Name No Pressure Type studio Artist Erick Sermon Cover NoPressure.jpg Caption Released October 1, 1993 Recorded 1992 1993 Genre Hip hop music Hip hop , East Coast hip hop Length 54 23 Label Def Jam Recordings Def Jam Producer Erick Sermon small Executive producer Music exec. small , Colin Wolfe Last album This album No Pressure br 1993 Next album Double or Nothing Erick Sermon album Double or Nothing br 1995 Singles Name No Pressure Type studio single 1 Hittin Switches single 1 date May 4, 1993 single 2 Stay Real single 2 date September 7, 1993 No Pressure is the solo debut studio album from United States American Hip hop music hip hop artist Erick Sermon , released in 1993 on Def Jam Recordings . The album peaked at number sixteen on the Billboard 200 Billboard 200 chart. Release and reception Album ratings rev1 Allmusic rev1Score Rating 4 5 ref name AllmscRvw cite web last Wynn first Ron title allmusic No Pressure Review url Allmusic class album id r190047 review pure url yes publisher Allmusic accessdate ... Bernard title No Pressure Music EW.com publisher Entertainment Weekly date 1993 10 15 url http www.ew.com ... name RRRvw cite web first Matt last Jost title Erick Sermon No Pressure Def Jam Rush Associated Labels ... allmusic No Pressure Charts & Awards Billboard Albums format work publisher Allmusic accessdate 2010 ..., and Sermon s mush mouthed, deadpan raps. Wynn ended his review stating that No Pressure is as much ... single pure url yes title allmusic No Pressure Charts & Awards Billboard Singles format work ... title allmusic No Pressure Credits format work publisher Allmusic accessdate 2010 11 22 ref arranging ... erences tags External links Allmusic class album id r190047 label No Pressure http www.discogs.com Erick Sermon No Pressure release 323644 No Pressure at Discogs Erick Sermon Category 1993 debut albums ... more details
In physics , chemistry and biology , a potential gradient is the local derivative rate of change of the potential with respect to displacement, i.e. spatial derivative, or gradient. This quantity frequently occurs in equations of physical processes because it leads to some form of flux . In electrical engineering it refers specifically to electric potential gradient, which is equal to the electric field . Definition Elementary algebra calculus Fundamentally the expression for a potential gradient F in one dimension takes the form ref Essential Principles of Physics, P.M. Whelan, M.J. Hodgeson, 2nd Edition, 1978, John Murray, ISBN 0 7195 3382 1 ref math F frac delta phi delta x , math where is some type of potential , and x is displacement not distance , in the x direction. In the limit of infinitesimal ... differentials math F frac rm d phi rm d x , math In three dimensions, the resultant potential gradient ..., which can be compactly and neatly written in terms of the gradient operator mathematics operator , math bold F nabla phi , math Vector calculus The mathematical nature of a potential gradient arises ... space. For any conservative vector field F , there exists a scalar field , such that the gradient ... can be shown to be conservative, it is equal to the gradient in gravitational potential math mathbf ... gradient and field are opposite in direction, as the potential gradient increases, the gravitational ... field has identical properties to the gravitational field it is the gradient of the electric potential ... to the gradient in electric potential, a time dependent term must be added ref Introduction to Electrodynamics ... , the Standard conditions for temperature and pressure standard electric potential difference is ref ... with superscript s o s denote the measurement is taken under Standard conditions for temperature and pressure standard conditions . The potential gradient is relatively abrupt, since there is an almost ... terms Category Fundamental physics concepts Category Vector calculus pl Gradient potencja u ... more details
In optimization mathematics optimization , gradient method is an algorithm to solve problems of the form math min x in mathbb R n f x math with the search directions defined by the gradient of the function at the current point. Examples of gradient method are the gradient descent and the conjugate gradient . See also col begin col break Gradient descent method Conjugate gradient method Derivation of the conjugate gradient method Nonlinear conjugate gradient method Biconjugate gradient method Biconjugate gradient stabilized method References cite book year 1997 title Optimization Algorithms and Consistent Approximations publisher Springer Verlag isbn 0 387 94971 2 author Elijah Polak Optimization algorithms DEFAULTSORT Gradient Method Category First order methods Category Optimization algorithms and methods Category Numerical linear algebra Category Gradient methods fr Algorithme du gradient ja ... more details
There are many possible applications for gradient copolymer like pressure sensitive adhesives ...Image Example of gradient copolymer.png 500px thumb Figure 1 Example of a a diblock copolymer, b gradient ... 1998 title Gradient Polymers and Copolymers journal Polymers for Advanced Technologies publisher John ... Gradient Copolymer journal Colloid Polym Sci publisher Springer volume 286 pages 1465 1474 doi 10.1007 ..., Stephen V. Arehart, Dorota Greszta and Tadeusz Pakula year 2000 title Gradient Copolymers by Atom Transfer ... Third pages 147 148 issn 8493 9813 ref In the gradient copolymer, as a result of the gradual compositional ... 2008 title Gradient Copolymers with Broad Glass Transition Temperature Regions Design of Purely ... of gradient copolymers because the synthesis of this group of novel polymers was now straightforward. Due to the similar properties of gradient copolymers to that of block copolymers, they have .... ref name E Polymer Composition Image Gradient Polym Composition2.png thumb right 300px Figure 2 Graphical depiction of the composition of a gradient copolymer In the gradient copolymer, there is a continuous ... can be depicted in a mathematical expression.The local composition gradient fraction math g ... of controlled radical polymerization CRP , gradient copolymers as distinguished from statistical copolymers were not synthetically possible. While a gradient can be achieved through compositional drift ... Kelly coauthors Krzysztof Matyjaszewski year 2002 title Statistical, Gradient, Block, and Graft Copolymers ... have been used to synthesize gradient copolymers. ref name E cite journal ref The gradient can be formed through either a spontaneous or a forced gradient. Spontaneous gradient polymerization is due ... creates an inconsistent gradient along the polymer. Forced gradient polymerization involves ... to achieve the desired gradient composition. Properties The wide range of composition possible in a gradient ... with the homopolymers. Micelles of the gradient copolymer can form when the gradient copolymer ... more details
distinguish gradient wind about the interaction of horizontal wind with the earth s surface a more general treatment of related phenomena wind shear In common usage, wind gradient , more specifically wind speed gradient ref name Hadlock cite book last Hadlock first Charles title Mathematical Modeling ... 088385709X pages quote Thus we have a wind speed gradient as we move vertically, and this has a tendency ... and below it. ref or wind velocity gradient , ref name Gorder1996 cite conference author Gorder, P.J. coauthors Kaufman, K. Greif, R. year 1996 title Effect of wind gradient on the trajectory synthesis ... wind velocity with altitude, the wind velocity gradient... ref or alternatively shear wind , ref cite ... 10.1111 j.1474 919x.2004.00295.x quote ...the shear wind gradient is rather weak....the energy gain...is due to a mechanism other than the wind gradient effect. ref is the vertical gradient of the mean ... pages 54 quote Therefore the vertical gradient of mean wind speed d dz is greatest over smooth terrain ... English publisher Routledge location New York year 2000 isbn 157958201X pages 104 quote wind gradient ... of the Earth , blowing directly towards the low pressure, when compared to the winds in the nearly ... layer, increasing vertical wind shear near the surface, also known as wind gradient. Background seealso ... drag force drag , there is a wind gradient in the wind flow just a few hundred meters above the Earth ... or wind gradient. ref due to the no slip condition . ref name Brown cite book last Brown first G. title ... Berlin year 2003 isbn 354040340X pages 17 ref Over a city or rough terrain, the wind gradient effect ... purposes, the wind gradient is modeled as a simple shear exhibiting a vertical velocity profile ... above ground where surface friction has a negligible effect on wind speed is called the gradient height and the wind speed above this height is assumed to be a constant called the gradient wind ... year 2005 isbn 1402028504 pages 73 ref For example, typical values for the predicted gradient height ... more details
gradient is analogous to the water pressure across a hydroelectric dam . Membrane transport ...cleanup jargon date October 2011 An electrochemical gradient is a gradient of electrochemical potential , usually for an ion that can move across membrane . The gradient consist of two parts, the electrical potential and a difference in the chemical concentration across a membrane. The difference of electrochemical potential s can be interpreted as a type of potential energy available for work in a cell. The energy is stored in the form of chemical potential , which accounts for an ion s concentration gradient across a cell membrane , and electrostatic energy , which accounts for an ion s tendency to move under influence of the transmembrane potential . Overview Electrochemical potential is important in electroanalytical chemistry and industrial applications such as batteries and fuel cells. It represents one of the many interchangeable forms of potential energy through which energy may be conservation ... or active transport across a membrane is determined by the electrochemical gradient. In mitochondria ... . An electrochemical gradient has two components. First, the electrical component is caused ... ATP to make a sodium ion gradient and a potassium ion gradient. The electrochemical potential is used ... gradients The proton gradient can be used as intermediate energy storage for heat production ... gradient . This is used by fermenting bacteria which do not have an electron transport chain, and hydrolyze ATP to make a proton gradient for flagella and the transportation of nutrients into the cell ... 2005 , for Biology 113 at the Ohio State University DEFAULTSORT Electrochemical Gradient Category Cellular ... Physical quantities Category Thermodynamics ca Gradient electroqu mic da Elektrokemisk gradient de Elektrochemischer Gradient es Gradiente electroqu mico fr Gradient lectrochimique id Gaya gerak proton lt Elektrocheminis gradientas nl Elektrochemische gradi nt pl Gradient elektrochemiczny ... more details
In vector calculus , the surface gradient is a Vector geometric vector differential operator that is similar to the conventional gradient . The distinction is that the surface gradient takes effect along a surface. For a surface math S math in a scalar field math u math , the surface gradient is defined and notated as ref R. Shankar Subramanian, http web2.clarkson.edu projects subramanian ch490 notes Boundary 20Conditions 20in 20Fluid 20Mechanics.pdf Boundary Conditions in Fluid Mechanics . ref math nabla S u nabla u mathbf hat n mathbf hat n cdot nabla u math where math mathbf hat n math is a unit Surface normal normal to the surface. Examining the definition shows that the surface gradient is the conventional gradient with the component normal to the surface removed subtracted , hence this gradient is tangent to the surface. In other words, the surface gradient is the orthographic projection of the gradient onto the surface. The surface gradient arises whenever the gradient of a quantity over a surface is important. In the study of capillary surface s for example, the gradient of spatially varying surface tension doesn t make much sense, however the surface gradient does and serves certain purposes. References Reflist Category Vector calculus bs Povr inski gradijent ... more details
Multiple issues unreferenced December 2009 orphan December 2009 wikify December 2009 Gradient related is a term used in multivariable calculus to describe a direction. A direction sequence math d k math is gradient related to math x k math if for any subsequence math x k k in K math that converges to a nonstationary point, the corresponding subsequence math d k k in K math is bounded and satisfies math limsup k rightarrow infty, k in K nabla f x k d k 0. math A gradient related direction is usually encountered in the gradient based iterative optimisation of a function math f math . At each iteration math k math the current vector is math x k math and we move in the direction math d k math , thus generating a sequence of directions. It is easy to guarantee that the directions we generate are gradient related, by for example setting them equal to the gradient at each point. DEFAULTSORT Gradient Related Category Vector calculus ... more details
In computer graphics, a color gradient sometimes called a color ramp or color progression specifies a range of position dependent color s, usually used to fill a region. ref cite book title SVG Essentials isbn 0596002238 last Eisenberg first J. David year 2002 publisher O Reilly Media pages 364 page 107 ref For example, many window managers allow the screen background to be specified as a gradient. The colors produced by a gradient vary continuously with position, producing smooth color transitions. Linear gradients File linear gradient.svg right A linear color gradient is specified by two points, and a color at each point. The colors along the line through those points are calculated using linear interpolation , then extended perpendicular to that line. In digital imaging systems, colors are typically interpolated in an RGB color space , often using gamma compression gamma compressed RGB color values, as opposed to linear. Circular gradients File radial gradient.svg right A circular gradient is specified as a circle that has one color and a focus the center of the circle that has another. Colors are calculated by linear interpolation based on distance from the focus. References reflist See also Wikibooks Colors Color gradient Image gradient Color banding Posterization Diffusion curve Category Computer graphics graphics software stub de Farbverlauf fr D grad de couleur nl Kleurengradi nt pl Gradient grafika ... more details
In mathematics , a skew gradient of a harmonic function over a simply connected domain with two real dimensions is a vector field that is everywhere orthogonal to the gradient of the function, and has the same Magnitude mathematics magnitude that the gradient has. Definition The skew gradient can be defined using complex analysis and the Cauchy Riemann equations . Let math f z x,y u x,y iv x,y math be a complex valued analytic function, where u , v are real valued scalar functions of the real variables x , y . A skew gradient is defined as math nabla perp u x,y nabla v x,y math and from the Cauchy Riemann equations , it is derived that math nabla perp u x,y frac partial u partial y , frac partial u partial x math Properties The skew gradient has two interesting properties. It is everywhere orthogonal to the gradient of u, and of the same length math nabla u x,y cdot nabla perp u x,y 0 , rVert nabla u rVert rVert nabla perp u rVert math References Refbegin Peter Olver, http www.math.umn.edu olver pdn.html Introduction to Partial Differential Equations, ch. 7, p. 232 Refend Category Differential calculus Category Generalizations of the derivative Category Linear operators in calculus Category Vector calculus ... more details
Stream gradient is the grade slope grade measured by the ratio of drop in a stream per unit distance, usually expressed as Foot length feet per mile or metre s per kilometre . Hydrology and geology A high gradient indicates a steep slope and rapid volumetric flow rate flow of water i.e. more ability to erode whereas a low gradient indicates a more nearly level stream bed and sluggishly moving water, that may be able to carry only small amounts of very fine sediment . High gradient streams tend to have steep, narrow V shaped valley s, and are referred to as young streams. Low gradient streams have wider and less rugged valley s, with a tendency for the stream to meander . Fluvial Erosion A stream that flows upon a uniformly erosion erodible substrate will tend to have a steep gradient near its source, and a low gradient nearing zero as it reaches its base level . Of course, a uniform substrate would be rare in nature hard layers of rock geology rock along the way may establish a temporary base level, followed by a high gradient, or even a waterfall , as softer materials are encountered below the hard layer. Human dam s, glaciation , changes in sea level , and many other factors can also change the normal or natural gradient pattern. Topographic mapping On topographic map s, stream Grade slope gradient can be easily approximated if the scale of the map and the contour intervals are known. Contour lines form a V shape on the map, pointing upstream. By counting the number of lines ... by the length of the stream segment you can determine the stream gradient. Because stream gradient is customarily given in feet per 1000 feet, one should then measure the amount a stream segment rises and the length of the stream segment in feet, then multiply feet per foot gradient by 1000 ... crossed on a map with ten foot contours, the gradient is approximately 5.7 feet per 1000 feet, a fairly steep gradient. See also Channel types Relief ratio Rapid s waterfall Types Types of waterfall ... more details
to indicate the direction of the gradient. Dark areas indicate higher values An image gradient is a directional ... from images. In graphics software for digital image editing , the term gradient is used for a gradual ... progression . Mathematically, the gradient of a two variable function here the image intensity ... s in the horizontal and vertical directions. At each image point, the gradient vector points in the direction of largest possible intensity increase, and the length of the gradient vector corresponds ... gradient, but is still of sufficient quality to be of practical use in many applications. More precisely ... the corresponding image gradient, and it uses only integer values for the coefficients which weight the image intensities to produce the gradient approximation. The gradient of the image is one of the fundamental building blocks in image processing . For example the Canny edge detector uses image gradient ... Computer vision File Intensity image with gradient images.png thumb 400px alt Left Black and white picture of a cat. Center The same cat, displayed in a gradient image in the x direction. Appears similar to an embossed image. Right The same cat, displayed in a gradient image in the y direction. Appears similar to an embossed image. On the left, an intensity image of a cat. In the center, a gradient image in the x direction measuring horizontal change in intensity. On the right, a gradient image in the y direction measuring vertical change in intensity. Gray pixels have a small gradient black or white pixels have a large gradient. Image gradients can be used to extract information from images. Gradient images are created from the original image generally by convolving with a filter, one of the simplest being the Sobel filter for this purpose. Each pixel of a gradient image measures the change ... of direction, gradient images in the x and y directions are computed. One of the most common uses is in edge detection. After gradient images have been computed, pixels with large gradient values ... more details
may be up to 7,000 K and the pressure could reach 360 GPa . ref cite journal author ... last Vlaar first N title Cooling of the earth in the Archaean Consequences of pressure release ... as geothermal energy . The geothermal gradient has been used for space heating and bathing since ... gradient varies with location and is typically measured by determining the bottom open hole temperature ... In areas of Holocene Tectonic uplift uplift and erosion Fig. 1 the initial gradient will be higher than .... If the gradient of the stabilized regime is projected above the inflection point to its intersect ... and Deposition sediment deposition Fig. 2 the initial gradient will be lower than the average until ..., M the thermal conductivity of the rocks there, and g the measured geothermal gradient. A representative ... Hence, using the global average geothermal conducting gradient of 0.02 K m we get that q 0.06 W m . This estimate ... gradient with periods varying from daily to tens of thousands of years and an amplitude which decreases ... a constant geothermal gradient throughout the Earth s surface. ref name Stacey If that rate of temperature ... S waves . The temperature gradient dramatically decreases with depth for two reasons. First ... by advection , or material transport. Thus, the geothermal gradient within the bulk of Earth s mantle is of the order of 0.3 kelvin per kilometer, and is determined by the adiabatic gradient associated ..., 2005 Refend Geophysics navbox Geothermal power DEFAULTSORT Geothermal Gradient Category Geological ... an Gradient cheotermico ca Gradient geot rmic da Geotermi de Geothermische Tiefenstufe es Gradiente geot rmico fr Gradient g othermique hr Geotermalni gradijent id Panas bumi it Gradiente geotermico hu Geotermikus gradiens nl Geotherm ja no Geotermi pl Gradient geotermiczny pt Gradiente ... more details
Unreferenced stub auto yes date December 2009 An environmental gradient is a gradual change in abiotic factors through space or time . Environmental gradients can be related to factors such as altitude, temperature, depth, ocean proximity and soil humidity. Species Abundance ecology abundance s usually change along environmental gradients in a more or less predictive way. However, the species abundance along an envronmental gradient is not only determined by the abiotic factor but, also by the change in the biotic interaction s along the environmental gradient. At an ecotone , species Abundance ecology abundance s change relatively quick compared to the environmental gradient. The species distribution along environmental gradients has been studied intensively due to large databases of species presence data e.g. Global Biodiversity Information Facility GBIF Environmental Gradients are linked to Connectivity and natural disturbance when considering river systems. A river restoration scheme must consider all of these factors before undertaking a program as these three factors are what leads to a larger biodiversity. Each species are not found in every type of habitat or in every part of the world. Within the environment there are multiple factors which affects organisms. The organisms in the polar region can not survive the climate at the equator. See also Biome , cline biology , thermocline . DEFAULTSORT Environmental Gradient Ecology stub Category Ecology ... more details
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