Histogramequalization is a method in image processing of contrast vision contrast adjustment using the image s Image histogramhistogram . Image Histogrammspreizung.png thumb right 300px Overview This method ... intensity intensities can be better distributed on the histogram. This allows for areas of lower local contrast to gain a higher contrast. Histogramequalization accomplishes this by effectively spreading ... . So in theory, if the histogramequalization function mathematics function is known, then the original histogram can be recovered. The calculation is not computation ally intensive. A disadvantage ... length , the small signal to noise ratio usually hampers visual detection. Histogramequalization ... process. Histogramequalization often produces unrealistic effects in photographs however it is very ... class of images that user would apply false color to. Also histogramequalization can produce undesirable ... ways to think about and implement histogramequalization, either as image change or as Palette ... image I unchanged then histogramequalization is implemented as Palette computing palette change ... contrast. Examples of such methods include adaptive histogramequalization and contrast limiting adaptive histogramequalization or CLAHE . Histogramequalization also seems to be used in biological ... Z. Naturforsch. volume 9 10 36 910 2 ref Histogramequalization is a specific case of the more general ... Histogramequalization of color images The above describes histogramequalization on a grayscale ... in the image. The cdf must be normalized to math 0,255 math . The general histogramequalization ... Hawkes Bay NZ.jpg thumb 300px The same image after histogramequalization Image Equalized Histogram.svg ... 54 Free histogramequalization plugin for Adobe Photoshop and PSP http fourier.eng.hmc.edu e161 lectures ... palette it will further reduce color depth number of unique shades of gray of the image. Histogramequalization will work the best when applied to images with much higher color depth than Palette computing ... more details
Adaptive histogramequalization is a computer image processing technique used to improve contrast vision contrast in images. It differs from ordinary histogramequalization in the respect that the adaptive method computes several histogram s, each corresponding to a distinct section of the image, and uses them to redistribute the lightness values of the image. Ordinary histogramequalization simply uses a single histogram for an entire image. Consequently, adaptive histogramequalization is considered an image enhancement technique capable of improving an image s local contrast , bringing out more detail in the image. However, it also can produce significant signal noise noise . A generalization of adaptive histogramequalization called contrast limited adaptive histogramequalization , also known as CLAHE , was developed to address the problem of noise amplification. See also Histogramequalization Shadow and highlight enhancement Clahe Category Image processing Compu graphics stub ... more details
Dablink For the histograms used in digital image processing, see Image histogram and Color histogram . Infobox quality tool image Histogram of arrivals per minute.svg category One of the Seven Basic Tools ... , a histogram is a graphical representation, showing a visual impression of the distribution ... introduced by Karl Pearson . ref name pearson cite doi 10.1098 rsta.1895.0010 ref A histogram consists ... by the width of the interval. The total area of the histogram is equal to the number of data. A histogram ... density function of the underlying variable. The total area of a histogram used for probability density is always normalized to 1. If the length of the intervals on the x axis are all 1, then a histogram is identical to a relative frequency plot. An alternative to the histogram is kernel density ... variable. The histogram is one of the Seven Basic Tools of Quality seven basic tools of quality ... 2010 02 05 ref Etymology Image Black cherry tree histogram.svg thumb left An example histogram of the heights of 31 Prunus serotina Black Cherry trees. The etymology of the word histogram is uncertain ... as the masts of a ship, the bar of a loom, or the vertical bars of a histogram and gramma drawing ... 2010 This rounding is a common phenomenon when collecting data from people. Image Travel time histogram total n Stata.png thumb 350px Histogram of travel time, US 2000 census. Area under the curve ... 40 5 4122 824 45 15 9200 613 60 30 6461 215 90 60 3435 57 This histogram shows the number of cases ... million . This type of histogram shows absolute numbers, with Q in thousands. br clear all Image Travel time histogram total 1 Stata.png thumb 350px Histogram of travel time, US 2000 census. Area under ... 0.0052 40 5 4122 0.0066 45 15 9200 0.0049 60 30 6461 0.0017 90 60 3435 0.0005 This histogram differs ... . This version shows proportions, and is also known as a unit area histogram. br clear all In other words, a histogram represents a frequency distribution by means of rectangles whose widths represent ... more details
About frequency dependent processing of audio signals Merge from Parametric equalization discuss Talk Equalization Merge parametric and blind equalization into equalization article date September 2010 Merge from Blind equalization discuss Talk Equalization Merge parametric and blind equalization into equalization article date September 2010 mergefrom Smiley face curve discuss Talk Equalization Smiley ... section has fully parametric EQ. Equalization , British equalisation is the process of adjusting the strength of certain frequencies within a Signal electronics signal . The most well known use of equalization ... and telecommunications. The circuit or equipment used to achieve equalization is called an equalizer ... line flat from end to end. However, in sound reproduction, equalization has come to mean .... The term EQ specifically refers to this variant of equalization. ref Ballou, pp.875 876 ... The Audio Dictionary Amplitude is not the only parameter equalization is applied to. Any frequency dependent parameter can be subject to equalization, and in particular phase equalization and time delay equalization can be important in telecommunications, especially lines carrying television signals .... Variable equalization was first used by John Volkman working at RCA in the 1920s. They were ... equalizer to use slide controls. It featured two passive equalization sections, a bass shelving ... system s, individual channels have equalization for aesthetic reasons, while the combined mix of sound is processed through equalization for practical reasons. Nearly any acoustic space absorbs ... waves produced by the size of the room and the materials in it. Equalization is used to compensate ... sound systems. One of the most direct uses of equalization is at a live event, where microphones and Loudspeaker ... audio records have had equalization applied to the sound waveform before the consumers record was made ... was used prior to 1940. Some 100 formulae were used until 1955, when the RIAA equalization RIAA standard ... more details
Equalization is correction for frequency dependent processing of audio signals. Equalization may also be Bandwidth equalization , in computer networking Equalization of pressure within the ear, a.k.a. ear clearing Financial processes Factor price equalizationEqualization payments Equalization pool Tax equalization Interest Equalization Tax Equalization, Anchor climbing Equalization sharing of load in anchors for rappelling and rock climbing Risk equalizationHistogramequalization Delay equalization See also Equalizer disambiguation disambig it Equalizzazione disambigua ... more details
File Histogram matching.PNG thumb 250px An example of histogram matching Histogram matching is a method in image processing of color mapping color adjustment of two images using the image Image histogram histograms . It is possible to use histogram matching to balance detector responses as a relative detector calibration technique. It can be used to normalize two images, when the images were acquired at the same local illumination such as shadows over the same location, but by different sensors, atmospheric conditions or global illumination. The algorithm Given two images, the reference and the adjusted images, we compute their histograms. Following, we calculate the Cumulative distribution function cumulative functions of the two images histograms math F 1 , math for the reference image and math F 2 , math for the target image. Then for each gray level math G 1 in 0,255 math , we find the gray level math G 2 , math for which math F 1 G 1 F 2 G 2 , math , and this is the result of histogram matching function math M G 1 G 2 , math . Finally, we apply the function math M , math on each pixel of the reference image. See also Histogramequalization Image histogram Color mapping Category Image processing photo stub it Histogram matching ... more details
axis represents the size of the area that is captured in each one of these zones. Thus, the histogram ... side and center of the graph. Conversely, the histogram for a very dark image will have the majority ... Image editors typically have provisions to create a histogram of the image being edited. The histogram ...&dq 22image histogram 22&lr &as brr 0&ei dvL2R yFI2AsgPP7Z2FCg&sig UoCi37U m3IUzm6fUG YB3za Y PPA136,M1 ... segmentation , and Co occurrence matrix co occurrence matrices . See also Histogram Image editing Color histogram , a multidimensional histogram of the distribution of color in an image HistogramequalizationHistogram matching References references External links http www.cambridgeincolour.com tutorials ... Histogram Category Image processing photo stub it Istogramma di una immagine ... more details
Orphan date November 2006 Unreferenced date July 2009 A profile histogram is a histogram where each bin contains the mean of its entries and possibly the corresponding Root mean square RMS . E.g. a 1D profile histogram gives for each value of X the mean value of Y. The term profile histogram is widely used in the high energy physics community. See also Physics Analysis Workstation PAW ROOT HippoDraw Scientific computing jHepWork External links http www.slac.stanford.edu grp ek hippodraw profilehist.png Profile histogram example DEFAULTSORT Profile Histogram Category Physics software ... more details
distinguish Image histogram In image processing and photography , a color histogram is a representation of the distribution of colors in an image . For digital images, a color histogram represents the number ... space , the set of all possible colors. The color histogram can be built for any kind of color space ... color space HSV . For monochromatic image s, the term intensity histogram may be used instead. For multi ..., beyond the three measurements in RGB , the color histogram is N dimensional, with N being ... small, each of those colors may be placed on a range by itself then the histogram is merely the count ... histogram may also be represented and displayed as a smooth Function mathematics function defined over the color space that approximates the pixel counts. Like other kinds of histogram s, the color histogram is a statistic that can be viewed as an approximation of an underlying continuous Frequency ... or any other color space of any dimension. A histogram of an image is produced first by discretization ... bin. For example, a Red Blue chromaticity histogram can be formed by first normalizing color pixel ... bins each. A two dimensional histogram of Red Blue chromaticity divide in to four bins N 4 might yield a histogram that looks like this table class wikitable align center align center colspan 2 rowspan ... 47 13 A histogram can be N dimensional. Although harder to display, a three dimensional color histogram ... . The histogram provides a compact summarization of the distribution of data in an image. The color histogram of an image is relatively invariant with translation and rotation about the viewing axis ... and matching the color content of one image with the other, the color histogram is particularly well ... the histogram to operate well in varying light levels. Example Histogram Data Given the following image of a cat an original version and a version that has been reduced to 256 colors for easy histogram purposes , the following data represents a color histogram in the RGB color space, using four bins ... more details
A Board of Equalization can refer to an agency of various governments that is responsible for functions related to taxation . United States State Board of Equalization California California State Board of Equalization Oklahoma State Board of Equalization disambig ... more details
Unreferenced date December 2006 Orphan date February 2009 In computing , equalization is a type of bandwidth management that makes adjustments to the flow of data along a computer network . By adding Latency engineering latency to low priority tasks, it ensures high priority tasks receive sufficient bandwidth. DEFAULTSORT Equalization Computing Category Computer networks Compu network stub ... more details
An equalization pool a fund created to level out differences in financial risk, often across long periods of time, in a process known as risk equalization . Examples include mandatory health insurance and grower co operatives. Health insurance In health insurance , equalization pools are used in countries such as Ireland , Australia , Germany and the Netherlands to balance risks amongst groups of people ... made basic health insurance compulsory and have created a risk equalization pool to even out differences ... must pay into the risk equalization pool and the older and sicker persons will receive money from the equalization pool. A government agency usually assigns the risks and manages the risk pool. Governments .... The presence of a risk equalization pool and a common health benefits system makes competition ... equalization regulations came into force SI No. 261 of 2003 with the aim to neutralize more equitably ... risk equalization transfers from insurers with low risk profiles to insurers with high risk ... of their members. Under the system, if the market equalization percentage the degree of difference between insurers risk profiles is less than 2 , the regulations specify that no risk equalization ... equalization constituted state aid, as transfers were likely to take place from BUPA Ireland to Vhi ... that transfers under the equalization scheme did not constitute state aid. BUPA withdrew from the Irish ... equalization levy. The Irish Supreme Court has since found in favour of the Irish company on the grounds that community rating is not the same as risk equalization, and the whole issue of VHI ... Health care in the Netherlands has since 2006 used a new system of health care based on a risk equalization ..., especially of perishable goods such as milk or fruit, equalization pools are sometimes used to even ... balance Some governments use equalization pools to achieve social balance, so that richer regions with fewer needs for state aid pay taxes into an equalization pool from which poorer regions needing ... more details
Orphan date February 2009 In signal processing , delay equalization corresponds to adjusting the relative phase waves phases of different frequencies to achieve a constant group delay , using by adding an all pass filter in series with an uncompensated filter. ref cite book last Qu lhas first MF coauthors Petraglia A year 2003 title Group Delay Equalization of Discrete Time Filters journal IEEE 2003 International Symposium on Industrial Electronics ISIE 2003 pages 924 927 ref Clever machine learning techniques are now being applied to the design of such filters. ref cite journal last i ka first P coauthors Laipert M year 2006 title Band pass Filter Group delay equalization journal Proceedings of the 38th Symposium on Systems Theory pages 289 293 ref References reflist 1 Category Signal processing Category Digital signal processing signal processing stub ... more details
Merge to Equalization discuss Talk Equalization Merge parametric and blind equalization into equalization article date September 2010 Unreferenced date January 2007 Blind equalization is a digital signal processing technique in which the transmitter transmitted Signal electrical engineering signal is inferred Equalizer communications equalized from the receiver information theory received signal, while making use only of the transmitted signal statistics. Hence, the use of the word blind in the name. Blind equalization is essentially blind deconvolution applied to digital communications . Nonetheless, the emphasis in blind equalization is on Online algorithm online estimation of the Equalization filter equalizer signal processing filter , which is the Inverse filter Inverse system inverse of the Channel communications channel impulse response , rather than the estimation of the channel impulse response itself. This is due to blind deconvolution common mode of usage in digital communications systems, as a mean to extract the continuously transmitted signal from the received signal, with the channel impulse response being of secondary intrinsic importance. The estimated equalizer is then convolution ... equalization problem can now be formulated as follows Given the received signal math r k math , find a filter math w k math , called an equalization filter, such that math hat s k sum n infty infty ... to the blind equalization problem is not unique. In fact, it may be determined only up to a signed ... k math Algorithms Many algorithms for the solution of the blind equalization problem have been suggested ... the blind equalization problem tractable. One such assumption, common to all algorithms described below ... the equalizer. See also Equalization Independent component analysis Principal components analysis ... Equalization Using the Constant Modulus Criterion A Review , PROCEEDINGS OF THE IEEE, VOL. 86, NO. 10, OCTOBER 1998. DEFAULTSORT Blind Equalization Category Telecommunication theory Category Signal processing ... more details
by many global companies is the implementation of a Tax Equalization policy. The principles behind a tax equalization policy is that the employee will not need to suffer neither a financial hardship ... usual home country taxes. In order to implement the tax equalization procedures, the company will have ... http www.expatexchange.com lib.cfm?articleID 718 Tax Equalization , Tax Advice by Tim Lenneman, CPA http www.expatsinitaly.com financial hypotax.html Hypo Tax Tax Equalization DEFAULTSORT Tax Equalization ... more details
Equalization payments are cash payments made in some federal systems of government from the federal government to subnational governments with the objective of offsetting differences in available revenue ... main Equalization payments in Canada Canadian Transfer Payments In Canada , the federal government makes ... to generate tax revenues. In 2009 2010, six provinces will receive 14.2 billion in equalization ... website on equalization payments ref Until the 2009 2010 fiscal year, Ontario was the only province to have never received equalization payments in 2009 2010 Ontario will receive 347 million, ref http ... called have province, and is now a net contributor that does not receive Equalization payments. Canada s territories are not included in the equalization program the federal government addresses territorial fiscal needs through the Territorial Formula Financing TFF program. Equalization payments ... the cost of providing services or the expenditure need of the provinces. Equalization payments ..., a so called have not province, pays more into equalization than a poorer citizen in Alberta, a so ... as a whole are net contributors to Equalization, while the citizens of New Brunswick are net receivers of Equalization payments. Equalization payments are one example of what are often collectively ... equalization can be spent in any way the provincial government desires. The payments help guarantee ... fiscal equalisation and iii Bundeserg nzungszuweisungen BEZ . Switzerland The first elements of an equalization .... External links General http aysps.gsu.edu isp world bank institute module.html The Design of Equalization ... features equalization program canada overview and contemporary issues Maple Leaf Web Equalization Program ... Equalization Program http www.strongontario.ca A Strong Ontario for a Stronger Canada http www.eqtff pfft.ca index.asp Expert Panel on Equalization and Territorial Formula Financing Australia http www.cgc.gov.au Commonwealth Grants Commission References reflist DEFAULTSORT Equalization Payments ... more details
Merge to Equalization discuss Talk Equalization Merge parametric and blind equalization into equalization article date September 2010 Refimprove date July 2007 Parametric equalizer or parametric EQ is an electronic multi band variable Equalization equalizer used in sound recording and Sound reinforcement system live sound reinforcement . Parametric equalizers allow Audio Engineer audio engineers to control the three primary parameters of an internal band pass filter which are amplitude , center frequency and Bandwidth signal processing bandwidth . Bandwidth is typically labeled Q on the unit, which stands for Q factor . The amplitude of each band can be controlled, and the center frequency can be shifted, and widened or narrowed. Most channel EQ sections on Mixing console Mixing Consoles made after the early 1970s are either semi or fully parametric equalizers Citation needed date March 2011 . Parametric equalizers are also sold as standalone outboard gear units. History Prior to the development of the parametric equalizer, equalizers used in recording studios or live productions were ... based on such technology ref George Massenburg, Parametric Equalization , presented at the 42nd convention ... equalization challenges. He presented a parametric equalizer consisting of three parametric channels ... recordings in particular. Using such parametric equalization stages, musicians and producers ... Parametric equalization is most often used to enhance frequencies which are not speaking well on a specific ... band that is overly resonant and reduce its volume. Reducing extraneous noises Parametric equalization ... cannot be fully removed with parametric equalization due to the harmonic content of many of these sounds, which would require extensive equalization which would end up drastically altering the tonal ... close to the speaker it is being sent to. Parametric equalization for feedback cancellation ... with the boundaries of the room in ways that make for uneven response. Parametric equalization can be used ... more details
Image RIAA EQ Curve.svg thumb 300px right The RIAA equalization curve for playback of vinyl records. RIAA equalization is a specification for the correct playback of gramophone record s, established by the Recording Industry Association of America RIAA . The purpose of the equalization is to permit greater ... from recording analog records without such equalization. The RIAA equalization curve was intended ... from 1940, each record company applied its own equalization there were over 100 combinations ..., and AES. The RIAA curve RIAA equalization is a form of preemphasis on recording, and deemphasis ... have to be carefully designed to avoid this. RIAA equalization is not a simple low pass filter. It carefully ... with the RIAA equalization curve, which adapts a magnetic cartridge to an unbalanced 10 ... standard. Special preamplifiers are also available for the various equalization curves used on pre ... audio samples using standard and custom equalization curves, removing the need for a dedicated hardware .... History Origins of pre emphasis unreferencedsection date December 2009 Equalization practice for electrical ... the RIAA curve. Over the years a variety of record equalization practices emerged and there was no industry ... little impact outside of the USA. The RIAA equalization only became a major international standard by the late 1970s when European recording labels slowly and finally began to adopt the RIAA equalization ... their own CCIR equalization. Hence the RIAA curve did not truly become a global standardization until the late 1980s. Further, even after officially agreeing to implement the RIAA equalization curve, many recording labels continued to use their own proprietary equalization even well into the 1970s .... To cloud the picture, some labels even saw different equalization curves being adopted from ... equalization curves existed but were named differently by different recording labels. Some small ... riaa uk riaa background 1.html Description and diagrams of RIAA equalization curve http www.euronet.nl ... more details
Risk equalization is a way of equalizing the risk profile s of insurance members in order to avoid loading Risk premium premium s on the insured to some predetermined extent. Health care In unregulated competitive market s for individual health insurance , risk rated premiums are observed to differ across subgroups of insured people, which are defined by rating factor s such as ageing age , gender , family size, geographic area because costs of care may be higher or lower in some coverage areas than others Profession occupation , length of contract period , the level of deductible , health status at time of enrollment, health habit psychology habits smoking , drinking , exercising and via differentiated bonus es for multi year no claim to prior costs. ref name VdV 2000 Van de Ven et al. 2000 ref Some nations that encourage private insurance for health care nevertheless seek to prevent insurers ... insurance market, the sponsor organizes it in the form of risk equalization among health insurers ..., the Subsidy Fund is called a Risk Equalization Fund REF . An insurer receives a relatively ..., and Ireland. The system of risk equalization plays a crucial role in order to reduce the incentives ... research results on the effectiveness of the 2004 Dutch risk equalization model. ref In practice, the sponsor ... status to include in the risk equalization model. ref http www.youtube.com watch?v 0wWNP deiiY ref References Stam PJA. Testing the effectiveness of risk equalization models in health insurance. PhD ... care system http www.youtube.com watch?v 3HeqJEbUptA The purpose of risk equalization, English version http www.youtube.com watch?v st1kP2WSnT8 The purpose of risk equalization, Dutch version http www.youtube.com watch?v 0wWNP deiiY Testing the effectiveness of risk equalization models, English version http www.youtube.com watch?v DNIPVH9tMxI Testing the effectiveness of risk equalization models, Dutch version Videos http www.youtube.com watch?v 3HeqJEbUptA A theoretical introduction to risk equalization ... more details
sections date September 2009 An equalization EQ filter is a filter signal processing filter , usually adjustable, designed to compensate for the unequal frequency response of some other signal processing circuit or system. ref Davis, Don and Carolyn, Sound System Engineering , p141 151, First Edition 1975. ref In audio engineer ing, the EQ filter is more often used creatively to alter the frequency response characteristics of a musical source or a sound mix. ref Ballou, p571. ref An EQ filter typically allows the user to adjust one or more parameters that determine the overall shape of the filter s transfer function . It is generally used to improve the fidelity of sound, to emphasize certain instruments, to remove undesired noises, or to create completely new and different timbre s. Equalizers may be designed with peaking filters, shelving filters, bandpass filters, or high pass and low pass filters. Dynamic range compression Dynamic range circuitry can be linked with an EQ filter to make timbre changes only after a signal passes an amplitude threshold, or to dynamically increase or reduce amplitude based on the level of a frequency band. Such circuitry is involved in de essing and in pop filtering. There are three primary types of equalizers with peaking filters parametric equalizer s graphic equalizers notch filters Parametric EQ Main Parametric equalizer Sometimes called presence filters equalizers with peaking filters normally have three user parameters Center Frequency Equalizers built on peaking filters use a form of bell curve not precisely the same as the gaussian function ... and is the frequency most affected by equalization. It is often notated as f sub c sub and expressed ... the sound power of the affected frequencies after equalization. However, a boost of around 10dB ... , IEEE Trans. Circuits and Systems , vol 31 , p5, 1984. ref See also Equalization Blind equalization Zobel network British EQ References reflist refbegin cite book last Ballou first Glen ... more details
In image processing , the balanced histogram thresholding method BHT ref A. Anjos and H. Shahbazkia. Bi Level Image Thresholding A Fast Method. BIOSIGNALS 2008. Vol 2. P 70 76. ref , is a very simple method used for automatic image thresholding . Like Otsu s Method ref Nobuyuki Otsu 1979 . A threshold selection method from gray level histograms . IEEE Trans. Sys., Man., Cyber. 9 62 66. ref and the Iterative Selection Thesholding Method ref Ridler TW, Calvard S. 1978 Picture thresholding using an iterative selection method, IEEE Trans. System, Man and Cybernetics, SMC 8 630 632. ref , this is a histogram based thresholding method. This approach assumes that the image is divided in two main classes The background and the foreground . The BHT method tries to find the optimum threshold level that divides the histogram in two classes. File Lovely spider.jpeg thumb 200px right Original image. File Lovely spider BHT.jpeg thumb 200px right Thresholded image. This method weighs the histogram, checks which of the two sides is heavier, and removes weight from the heavier side until it becomes the lighter. It repeats the same operation until the edges of the weighing scale meet. Given its simplicity, this method is a good choice as a first approach when presenting the subject of automatic image ... Histogram Thresholding method code int BHThreshold int histogram i m int i s i e 2.0f center of the weighing scale I m w l get weight i s, i m 1, histogram weight on the left W l w r get weight i m 1, i e 1, histogram weight on the right W r while i s i e if w r w l right side is heavier w r histogram i e if i s i e 2 i m w r histogram i m w l histogram i m else if w l w r left side is heavier w l histogram i s if i s i e 2 i m w l histogram i m 1 w r histogram i m 1 i m return i m code File ... the extremities of the histogram. ref A. Anjos, R. Leite, M. L. Cancela, H. Shahbazkia. MAQ ... BHThresholding.jar ImageJ Plugin DEFAULTSORT Balanced Histogram Thresholding Category Image processing ... more details
In neurophysiology , peristimulus time histogram and poststimulus time histogram , both abbreviated PSTH or PST histogram , are histogram s of the times at which neurons fire. These histograms are used to visualize the rate and timing of neuronal spike discharges in relation to an external stimulus or event. The peristimulus time histogram is sometimes called perievent time histogram , and post stimulus and peri stimulus are often hyphen ated. The prefix peri, for through, is typically used in the case of periodic stimuli, in which case the PSTH show neuron firing times wrapped to one cycle of the stimulus. The prefix post is used when the PSTH shows the timing of neuron firings in response to a stimulus event or onset. ref cite book title Introduction to Electrophysiological Methods and Instrumentation author Franklin Bretschneider and Jan R. De Weille url http books.google.com ?id 2ybw9UoRVBUC&pg PA188&dq peri stimulus time histogram post stimulus time histogram publisher Academic Press isbn 0123705886 year 2006 ref To make a PSTH, a spike train recorded from a single neuron is aligned with the onset, or a fixed phase point, of an identical stimulus repeatedly presented to an animal. The aligned sequences are superimposed in time, and then used to construct a histogram. ref cite journal last Palm first G. authorlink coauthors Aertsen, A. M. Gerstein, G. L. title On the significance of correlations among neuronal spike trains journal Biological Cybernetics volume 59 issue 1 pages 1 11 publisher date 1988 doi 10.1007 BF00336885 id accessdate pmid 3401513 ref Construction procedure Align spike sequences with the onset of stimuli that repeated n times. For periodic stimuli, wrap the response sequence back to time zero after each time period T , and count n as the total number ... a bar graph histogram with the bar height of bin i given by math frac k i n Delta math in units of estimated ... of a time histogram journal Neural Computation volume 19 issue 6 pages 1503 152 publisher date 2007 ... more details
Information Description Histogram chart test of KEM Source I created this image by using JFreeChart. Date 2008 5 27 Author User Abhaac font color red J font font color purple n font font color blue W font User talk Abhaac sup talk sup other versions GFDL self migration relicense ... more details
In robotics , Vector Field Histogram VFH is a real time motion planning algorithm proposed by Johann Borenstein and Yoram Koren in 1991. ref name Borenstein1991 cite journal author Borenstein, J. coauthors Koren, Y. year 1991 title The vector field histogram fast obstacle avoidance for mobilerobots journal Robotics and Automation, IEEE Transactions on volume 7 issue 3 pages 278 288 url http ieeexplore.ieee.org xpls abs all.jsp?arnumber 88137 accessdate 2008 06 30 doi 10.1109 70.88137 ref The VFH utilizes a statistical representation of the robot s environment through the so called histogram grid, and therefore place great emphasis on dealing with uncertainty from sensor and modeling errors. Unlike other obstacle avoidance algorithms, VFH takes into account the dynamics mechanics dynamics and shape of the robot, and returns steering commands specific to the platform. While considered a local path planner, i.e., not designed for global path optimality, the VFH has been shown to produce near optimal paths. The original VFH algorithm was based on previous work on Virtual Force Field , a local path planning algorithm. After its creation in 1991, VFH was updated in 1998 by Iwan Ulrich and Johann Borenstein , and renamed VFH unofficially Enhanced VFH . ref name Ulrich1998 cite conference author Ulrich, I. coauthors Borenstein, J. year 1998 title VFH reliable obstacle avoidance for fast mobile robots conference booktitle Robotics and Automation, 1998. Proceedings. 1998 IEEE International ... driver vfh.html VFH in Player Stage Gazebo ref VFH The Vector Field Histogram was developed with the aim ... histogram grids see also occupancy grid . Such representation is well suited for inaccurate sensor ... three major components Cartesian histogram grid a two dimensional Cartesian histogram grid is constructed ... updated in real time. Polar histogram a one dimensional polar histogram is constructed by reducing the Cartesian histogram around the momentary location of the robot. Candidate valley consecutive ... more details
Orphan date February 2009 Dose volume histogram DVH , a concept used in radiation treatment planning ref Drzymala et al. Dose Volume Histograms. Intl J Rad Oncology, Biology and Physics 21, 1991, 71 78 ref . DVHs were introduced by Goitein and Verhey in 1979 in a publication by Shipley et al. ref Phys. Med. Biol. 50 2005 L17 L19 ref . The purpose of a DVH is to summarize 3D dose distributions in a graphical 2D format. In modern radiation therapy, 3D dose distributions are typically created in a computerized treatment planning system based on a 3D reconstruction of a Computed tomography CT scan. The volume referred to in DVH analysis can be a target of radiation treatment, a healthy organ nearby a target, or an arbitrary structure. DVHs can be visualized in either of two ways differential DVHs or cumulative DVHs. A DVH is created by first determining the size of the dose bins of the histogram . Bins can be of arbitrary size, e.g. 0 1 Gy, 1.001 2 Gy, 2.001 3 Gy, etc. In a differential DVH, bar or column height indicates the volume of structure receiving a dose given by the bin. Bin doses are along the horizontal axis, and structure volumes either percent or absolute volumes are on the vertical. The differential DVH takes the appearance of a typical histogram. The cumulative DVH is plotted with bin doses along the horizontal axis, as well. However, the column height of the first bin 0 1 Gy, e.g. represents the volume of structure receiving greater than or equal to that dose. The column height of the second bin 1.001 2 Gy, e.g. represents the volume of structure receiving greater than or equal to that dose, etc. With very fine small bin sizes, the cumulative DVH takes on the appearance of a smooth line graph. The lines always slope and start from top left to bottom right. For a structure receiving a very homogenous dose 100 of the volume receiving exactly 10 Gy for example the cumulative DVH will appear as a horizontal line at the top of the graph, at 100 volume as plotted ... more details
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