The Taylor series truncation error of the central differencing scheme is second order. Central differencing scheme will be accurate only if Pe < 2\. Owing to this limitation, central differencing is not a suitable discretisation practice for general purpose flow calculations.
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Among all the traditional moving object detection methods, we could categorize them into four major approaches: Background subtraction, Frame differencing, Temporal Differencing, and Optical Flow.
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The term differential compression is used to emphasize the data differencing connection.
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Data compression can be viewed as a special case of data differencing. Data differencing consists of producing a difference given a source and a target, with patching reproducing the target given a source and a difference. Since there is no separate source and target in data compression, one can consider data compression as data differencing with empty source data, the compressed file corresponding to a difference from nothing. This is the same as considering absolute entropy (corresponding to data compression) as a special case of relative entropy (corresponding to data differencing) with no initial data.
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Nguyen produced the Unified CodeCount (UCC) system design as a framework and the existing code counters and differencing tool were merged into it. Additional features like unified counting and differencing capabilities, detecting duplicate files, support for text and CSV output files, etc. were also added. A presentation on "Unified Code Count with Differencing Functionality" was presented in the 24th International Forum on COCOMO in October 2009.
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For ARIMAs with different orders of differencing, RMSE can be used for model comparison.
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Block diagram of the CDTA. Current differencing transconductance amplifier (CDTA) is a new active circuit element.
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In his original work, Hirt treated this with a blended scheme consisting of controlled downwinding and upwind differencing.
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Temporal differencing method identifies the moving object by applying pixel-wise difference method with two or three consecutive frames.
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The Differencing calculator was a manually operated device which was designed to assist additive recovery in super- enciphered cipher coded messages, by speeding the differencing of depth of super-enciphered (codegroups) and the trail of likely additives therein. The machine cost of ℛℳ46 Reichsmarks, $40.00 at 1945 conversion rates. It was identical to the US Navy CXDG-CNN-10ADW, code name "Fruit" often called the NCR differencing calculator. The German version had a capacity of thirty 5-figure code groups, as against the NCR capacity of 20.
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In the higher order differencing schemes, as the name suggests, the convective transport equation is discretized with higher order or blended differencing schemes. Such methods include the Compressive Interface Capturing Scheme for Arbitrary Meshes (CICSAM) and High Resolution Interface Capturing (HRIC) scheme, which are both based on the Normalized Variable Diagram (NVD) by Leonard.
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Liquid XML Studio provides an XML aware differencing tool to compare XML documents. The tool is based on the Zhang-Shasha algorithm.
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One way to make some time series stationary is to compute the differences between consecutive observations. This is known as differencing. Transformations such as logarithms can help to stabilize the variance of a time series. Differencing can help stabilize the mean of a time series by removing changes in the level of a time series, and so eliminating trend and seasonality.
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The different methods for treating VOF can be roughly divided into three categories, namely the donor-acceptor formulation, higher order differencing schemes and line techniques.
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A field sign is an unofficial differencing mark worn on a combatant's clothing to show the difference between friend and foe or a combatant and a civilian.
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PhantomJS was made for programmatic control of web sites and has been used for many purposes from visual differencing of websites to automated testing of JavaScript frameworks.
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The differencing capability allows users to count the number of added/new, deleted, modified, and unmodified logical SLOC of the current version in comparison with the previous version.
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In computer science and information theory, data differencing or differential compression is producing a technical description of the difference between two sets of data – a source and a target. Formally, a data differencing algorithm takes as input source data and target data, and produces difference data such that given the source data and the difference data, one can reconstruct the target data ("patching" the source with the difference to produce the target).
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The encoder performs the function of differentiation; a quantizer precedes the differencing of adjacent quantized samples; the decoder is an accumulator, which if correctly initialized exactly recovers the quantized signal.
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Figure 1.Comparison of different schemes In applied mathematics, the central differencing scheme is a finite difference method that optimizes the approximation for the differential operator in the central node of the considered patch and provides numerical solutions to differential equations.Computational fluid dynamics –T CHUNG, It is one of the schemes used to solve the integrated convection–diffusion equation and to calculate the transported property Φ at the e and w faces, where e and w are short for east and west (compass directions being customarily used to indicate directions on computational grids). The method's advantages are that it is easy to understand and implement, at least for simple material relations; and that its convergence rate is faster than some other finite differencing methods, such as forward and backward differencing.
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Box and Jenkins recommend the differencing approach to achieve stationarity. However, fitting a curve and subtracting the fitted values from the original data can also be used in the context of Box–Jenkins models.
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From a historical point of view, shock- capturing methods can be classified into two general categories: classical methods and modern shock capturing methods (also called high-resolution schemes). Modern shock-capturing methods are generally upwind biased in contrast to classical symmetric or central discretizations. Upwind-biased differencing schemes attempt to discretize hyperbolic partial differential equations by using differencing based on the direction of the flow. On the other hand, symmetric or central schemes do not consider any information about the direction of wave propagation.
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In statistics, autoregressive fractionally integrated moving average models are time series models that generalize ARIMA (autoregressive integrated moving average) models by allowing non-integer values of the differencing parameter. These models are useful in modeling time series with long memory—that is, in which deviations from the long-run mean decay more slowly than an exponential decay. The acronyms "ARFIMA" or "FARIMA" are often used, although it is also conventional to simply extend the "ARIMA(p,d,q)" notation for models, by simply allowing the order of differencing, d, to take fractional values.
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Image differencing is an image processing technique used to determine changes between images. The difference between two images is calculated by finding the difference between each pixel in each image, and generating an image based on the result. For this technique to work, the two images must first be aligned so that corresponding points coincide, and their photometric values must be made compatible, either by careful calibration, or by post-processing (using color mapping). The complexity of the pre-processing needed before differencing varies with the type of image.
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In computational fluid dynamics QUICK, which stands for Quadratic Upstream Interpolation for Convective Kinematics, is a higher-order differencing scheme that considers a three-point upstream weighted quadratic interpolation for the cell face values. In computational fluid dynamics there are many solution methods for solving the steady convection–diffusion equation. Some of the used methods are the central differencing scheme, upwind scheme, hybrid scheme, power law scheme and QUICK scheme. The QUICK scheme was presented by Brian P. Leonard – together with the QUICKEST (QUICK with Estimated Streaming Terms) scheme – in a 1979 paper.
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The Portuguese systems of differencing have their origins in the regulations of King Manuel I, who ruled Portugal from 1485 to 1521. There are two systems, one for the non-Royal families and the other for the Royal House.
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The Unified CodeCount Toolset with Differencing Functionality (UCC) is a collection of tools designed to automate the collection of source code sizing and change information. The UCC runs on multiple programming languages and focuses on two possible Source Lines of Code (SLOC) definitions, physical and/or logical. The Differencing functionality can be used to compare two baselines of software systems and determine change metrics: SLOC addition, deletion, modification, and non-modification counts. The UCC toolset is copyright USC Center for Software Engineering but is made available with a Limited Public License which allows anyone to make modifications on the code.
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To deliver this reduction in the size of the required data updates across a portal, geo-replication systems often use differencing engine technologies. These systems are able to difference the content of each portal server right down to the byte level. This knowledge of the content that is already on each server enables the system to rebuild any changes to the content on one server, across each of the other servers in the deployment from content already hosted on those other servers. This type of differencing system ensures that no content, at the byte level, is ever sent to a server twice.
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Longitudinal studies of secular events are frequently conceptualized as consisting of a trend component fitted by a polynomial, a cyclical component often fitted by an analysis based on autocorrelations or on a Fourier series, and a random component (stochastic drift) to be removed. In the course of the time series analysis, identification of cyclical and stochastic drift components is often attempted by alternating autocorrelation analysis and differencing of the trend. Autocorrelation analysis helps to identify the correct phase of the fitted model while the successive differencing transforms the stochastic drift component into white noise. Stochastic drift can also occur in population genetics where it is known as genetic drift.
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The systematics of the genus Pelagosaurus are confused, with differencing topologies placing it as either a teleosaurid,Gasparini Z, Pol D, Spalletti LA. 2006. An unusual marine crocodyliform from the Jurassic-Cretaceous boundary of Patagonia. Science 311: 70-73. or as the sister taxon to a Teleosauridae + Metriorhynchoidea clade.
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Block diagram of the CDBA A current differencing buffered amplifier (CDBA) is a multi-terminal active component with two inputs and two outputs and developed by Cevdet Acar and Serdar Özoğuz. Its block diagram can be seen from the figure. It is derived from the current feedback amplifier (CFA).
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Montagu took for his crest "a griffin issuing from a ducal crown". His coat of arms was the Neville "Gules a saltire argent" with a label "gobony argent and azure crescent" for differencing, as a younger son. This coat, when he was made Marquis of Montagu, was later augmented with further quarterings.
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Main concerns for data differencing are usability and space efficiency (patch size). If one simply wishes to reconstruct the target given the source and patch, one may simply include the entire target in the patch and "apply" the patch by discarding the source and outputting the target that has been included in the patch; similarly, if the source and target have the same size one may create a simple patch by XORing source and target. In both these cases, the patch will be as large as the target. As these examples show, if the only concern is reconstruction of target, this is easily done, at the expense of a large patch, and the main concern for general-purpose binary differencing is reducing the patch size.
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The Unified CodeCount (UCC) produces the counting by capturing the LSLOC strings from a file based on a counting specification document created for each language; this specification is proposed as a standard. The differencing feature compares the LSLOC strings from the two files captured during the counting process with the help of a common engine.
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The MacCormack method is well suited for nonlinear equations (Inviscid Burgers equation, Euler equations, etc.) The order of differencing can be reversed for the time step (i.e., forward/backward followed by backward/forward). For nonlinear equations, this procedure provides the best results. For linear equations, the MacCormack scheme is equivalent to the Lax–Wendroff method.
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Instead of using traditional approach, to use image subtraction operator by subtracting second and images afterwards, frame differencing method make comparisons between two successive frames to detect moving targets., Jain, R. and H. Nagel, “On the Accumulative Difference Pictures for the Analysis of Real World Scene Sequences,” IEEE Tran. on Pattern Anal. Mach. Intell., pp.
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H.K Versteeg & W. Malalasekera . An introduction to Computational Fluid Dynamics.Chapter:5. Figure 5.5.H.K Versteeg & W. Malalasekera . An introduction to Computational Fluid Dynamics.Chapter:5. Figure 5.13. Therefore the upwind differencing scheme is applicable for Pe > 2 for positive flow and Pe < −2 for negative flow. For other values of Pe, this scheme doesn’t give effective solution.
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Accuracy Based on the backward differencing formula, the accuracy is only first order on the basis of the Taylor series truncation error. It gives error when flow is not aligned with grid lines. Distribution of transported properties become marked giving diffusion-like appearance, called as the false diffusion. Refinement of grid serves in overcoming the issue of false diffusion.
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14), as cited in Mills & Patterson (2013, p. 11). An furthermore: > The quadrature method therefore applies cumulation to obtain a series > representing the integral function, and differencing to obtain a series of > data representing the derivative. Karsten suggested in this theory, that "the aim of correlation analysis should ultimately be the recovery of causal connections."Marcel Boumans (2004).
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Commandeur & Koopman (2007, §10.4) argue that the Box–Jenkins approach is fundamentally problematic. The problem arises because in "the economic and social fields, real series are never stationary however much differencing is done". Thus the investigator has to face the question: how close to stationary is close enough? As the authors note, "This is a hard question to answer".
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On August 15, 2012, Ilesfay received US patent #8,244,831 titled Method for the Preemptive Creation of Binary Delta Information within a Computer Network for their cloud-based delta encoding/binary differencing methods. On March 26, 2013, Ilesfay received US patent #8,407,315 titled Method for Horizontal Scale Delta Encoding. On November 26, 2013, Ilesfay received US patent #8,595,187 titled Serialization for Delta Encoding.
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At the end of phase one, the single remaining number is the difference of the two subset sums. The second phase reconstructs the actual solution. The differencing heuristic performs better than the greedy one, but is still bad for instances where the numbers are exponential in the size of the set. The following Java code implements the first phase of Karmarkar–Karp.
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This non-uniqueness is in keeping with the abstract mathematical nature of the internal energy. The internal energy is customarily stated relative to a conventionally chosen standard reference state of the system. The concept of internal energy is considered by Bailyn to be of "enormous interest". Its quantity cannot be immediately measured, but can only be inferred, by differencing actual immediate measurements.
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K Versteeg & W. Malalasekera . An introduction to Computational Fluid Dynamics.Chapter:5.Page 118(5.6.1.1). The upwind differencing scheme formulation is conservative. BoundednessH.K Versteeg & W. Malalasekera . An introduction to Computational Fluid Dynamics.Chapter:5.Page 118 (5.6.1.2). As the coefficients of the discretised equation are always positive hence satisfying the requirements for boundedness and also the coefficient matrix is diagonally dominant therefore no irregularities occur in the solution.
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The VHD format has a built-in limitation of just under 2 TiB (2040 GiB) for the size of any dynamic or differencing VHDs. This is due to a sector offset table that only allows for the maximum of a 32-bit quantity. It is calculated by multiplying 232 by 512 bytes for each sector. The formula in the VHD specification allows a maximum of sectors.
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It requires that transportiveness changes according to magnitude of peclet number i.e. when pe is zero \varphi is spread in all directions equally and as Pe increases (convection > diffusion) \varphi at a point largely depends on upstream value and less on downstream value. But central differencing scheme does not possess transportiveness at higher pe since Φ at a point is average of neighbouring nodes for all Pe.
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For example, if observations are available at T time periods, then after first differencing, only T-1 lags are usable. Then, if K lags of the dependent variable are used as instruments, only T-K-1 observations are usable in the regression. This creates a trade-off: adding more lags provides more instruments, but reduces the sample size. The Arellano–Bond method circumvents this problem.
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Historically, it was recognised that there was a need to difference the arms of the head of the family from those of cadets. This need was recognised in Europe during the 14th century; various means to accomplish this were utilized. In the modern era, differencing arms is generally rarely done in Continental Europe. It is only in Scotland where the need to difference cadets is enforced.
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If the differencing scheme produces coefficients that satisfy the above criterion the resulting matrix of coefficients is diagonally dominant. To achieve diagonal dominance we need large values of net coefficient so the linearisation practice of source terms should ensure that SP is always negative. If this is the case –SP is always positive and adds to aP. Diagonal dominance is a desirable feature for satisfying the boundedness criterion.
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Quasi-experimental approaches can remove bias arising from selection on observables and, where panel data are available, time invariant unobservables. Quasi-experimental methods include matching, differencing, instrumental variables and the pipeline approach; they are usually carried out by multivariate regression analysis. If selection characteristics are known and observed, they can be controlled for to remove the bias. Matching involves comparing program participants with non-participants based on observed selection characteristics.
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Instead, one includes the order of the seasonal terms in the model specification to the ARIMA estimation software. However, it may be helpful to apply a seasonal difference to the data and regenerate the autocorrelation and partial autocorrelation plots. This may help in the model identification of the non- seasonal component of the model. In some cases, the seasonal differencing may remove most or all of the seasonality effect.
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Just as absolute entropy serves as theoretical background for data compression, relative entropy serves as theoretical background for data differencing – the absolute entropy of a set of data in this sense being the data required to reconstruct it (minimum compressed size), while the relative entropy of a target set of data, given a source set of data, is the data required to reconstruct the target given the source (minimum size of a patch).
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Optical DownConverter (ODC) is an example of a non-linear optical process, in which two beams of light of different frequencies \omega_1 and \omega_2 interact, creating microwave with frequency \omega_3 = \omega_1 - \omega_2 . It is a generalization of microwave. In the latter, \omega_1 = \omega_2, both of which can be provided by a single light source. From a quantum mechanical perspective, ODC can be seen as result of differencing two photons to produce a microwave.
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Traditionally, there was very little in the way of time zone support for JavaScript. Essentially the programmer had to extract the UTC offset by instantiating a time object, getting a GMT time from it, and differencing the two. This does not provide a solution for more complex daylight saving variations, such as divergent DST directions between northern and southern hemispheres. ECMA-402, the standard on Internationalization API for JavaScript, provides ways of formatting Time Zones.
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There are two coats of arms often associated with the family name Hollister; however, it has not been shown that either have been officially linked to the name, since coats of arms are associated with individuals, not surnames. Coats of arms cannot automatically be claimed by any member of a family. The coat of arms is bestowed on an individual and is passed to the eldest child (usually son). Younger children officially have to use differencing when displaying arms.
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Blank and comment lines are not counted. Logical SLOC (LSLOC)– Lines of code intended to measure "statements", which normally terminate by a semicolon (C/C++, Java, C#) or a carriage return (VB, Assembly), etc. Logical SLOC are not sensitive to format and style conventions, but they are language dependent. The Unified CodeCount(UCC) differencing capability allows the user to count, compare, and collect logical differentials between two versions of the source code of a software product.
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Another heuristic is the largest differencing method (LDM), also called the Karmarkar–Karp heuristic after the pair of scientists that published it in 1982. LDM operates in two phases. The first phase of the algorithm takes the two largest numbers from the input and replaces them by their difference; this is repeated until only one number remains. The replacement represents the decision to put the two numbers in different sets, without immediately deciding which one is in which set.
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German noble houses did not use cadency marks as systematically as their European peers. A nobleman's sons were not generally obliged or expected not to bear their father's arms and often did just so. The most common means of differencing was the use of different heraldic crests to mark apart otherwise identical achievements borne by different branches of a family. Other, less frequent forms include counter-changing or the replacement of individual tinctures, or the addition of ordinaries.
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SIGGRAPH Asia 2012 in Singapore also introduced a native Android application and the very first 3D differencing tool Interactive 3D Diff. Subsequent collaboration with Prof Niloy Mitra at University College London led to the development of a reverse engineering system 3D Timeline presented at Eurographics 2014 in Strasbourg, France. Unlike Interactive 3D Diff which required prior correspondence information, i.e. matching object-level identifiers between revisions, 3D Timeline reverse engineered the relationships and changes between 3D components over multiple revisions without prior correspondence.
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Color mapping can serve two different purposes: one is calibrating the colors of two cameras for further processing using two or more sample images, the second is adjusting the colors of two images for perceptual visual compatibility. Color calibration is an important pre-processing task in computer vision applications. Many applications simultaneously process two or more images and, therefore, need their colors to be calibrated. Examples of such applications are: Image differencing, registration, object recognition, multi-camera tracking, co-segmentation and stereo reconstruction.
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Composition with Red Blue and Yellow (1930) by Piet Mondrian (Dutch, 1872–1944) The arrival of Modernism in the late 19th century lead to a radical break in the conception of the function of art,Griselda Pollock, Differencing the Canon. Routledge, London & New York, 1999. and then again in the late 20th century with the advent of postmodernism. Clement Greenberg's 1960 article "Modernist Painting" defines modern art as "the use of characteristic methods of a discipline to criticize the discipline itself".
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Random effect models assist in controlling for unobserved heterogeneity when the heterogeneity is constant over time and not correlated with independent variables. This constant can be removed from longitudinal data through differencing, since taking a first difference will remove any time invariant components of the model. Two common assumptions can be made about the individual specific effect: the random effects assumption and the fixed effects assumption. The random effects assumption is that the individual unobserved heterogeneity is uncorrelated with the independent variables.
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NEO focused surveys revisit the same area of sky several times in succession. Movement can then be detected using image differencing techniques. Anything that moves from image to image against the background of stars is compared to a catalogue of all known objects, and if it is not already known is reported as a new discovery along with its precise position and the observation time. This then allows other observers to confirm and add to the data about the newly discovered object.
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The differencing calculator with recording (German:Differenzen Rechengereat, English:Differencing Calculating Apparatus) was a machine designed to compute a flag of difference for a set of enciphered code groups and record them. It consisted of two teleprinter tapes with photoelectric reading heads, a set of calculating relays and a recording electric teleprinter. The read heads operated at seven characters a second, bounded by the speed of the teleprinter where time was lost by the carriage return and line feed. It cost ℛℳ920 Reichsmarks, $800.00 at 1945 conversion rates.
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Gravity measurements are a reflection of the earth's gravitational attraction, its centripetal force, tidal accelerations due to the sun, moon, and planets, and other applied forces. Gravity gradiometers measure the spatial derivatives of the gravity vector. The most frequently used and intuitive component is the vertical gravity gradient, Gzz, which represents the rate of change of vertical gravity (gz) with height (z). It can be deduced by differencing the value of gravity at two points separated by a small vertical distance, l, and dividing by this distance.
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The beta versions are tested by industry Affiliates, and then released to the public as open source code. In 2006, work was done to develop a differencing tool which would compare two software system baselines to determine the differences between two versions of software. The CodeCount tool set, which is a precursor of UCC, was released in the year 2007. It was a collection of standalone programs written in a single language to measure source code written in languages like COBOL, Assembly, PL/1, Pascal, and Jovial.
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Many available CFD tools, such as CFX, Fluent, Star CCM++ with different models as RNG k-ε turbulence models with hybrid and CONDIF upwind differencing schemes has been used for analysis purpose and the data obtained with these analysis helped in modifying the burner design in turn lowering the adverse effect on the environment due to NOx formation during combustion.P. J Stopford, “Recent Application of CFD Modeling in the Power Generation and Combustion Industries”, Applied Mathematical Modeling, Vol 26, Pg. No. 351-374, 2002.
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Burroughs Corporation in about 1912 built a machine for the Nautical Almanac Office which was used as a difference engine of second-order. It was later replaced in 1929 by a Burroughs Class 11 (13-digit numbers and second-order differences, or 11-digit numbers and [at least up to] fifth-order differences). Alexander John Thompson about 1927 built integrating and differencing machine (13-digit numbers and fifth-order differences) for his table of logarithms "Logarithmetica britannica". This machine was composed of four modified Triumphator calculators.
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Roedecker realizes that, through image differencing, the two messages contain additional information—a sound clip from The Mikado, known to be Avatar's favourite operetta. Black determines that another set of numbers visible on the feed are latitude and longitude co-ordinates for San Francisco. The San Francisco Police Department are uncooperative, however. After Black, Roedecker and Watts attempt to keep the feed counter from rising by recreating the live feed and substituting it, the second girl is murdered before the feed's counter reaches the allotted number.
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In addition, although not strictly part of the prediction process, once an impact has been predicted, an appropriate response needs to be made. Most asteroids are discovered by a camera on a telescope with a wide field of view. Image differencing software compares a recent photograph with earlier ones of the same part of the sky, detecting objects that have moved, brightened, or appeared. Those systems usually obtain a few observations per night which can be linked up into a very preliminary orbit determination.
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In the statistical analysis of time series, a trend-stationary process is a stochastic process from which an underlying trend (function solely of time) can be removed, leaving a stationary process.About.com economics Online Glossary of Research Economics The trend does not have to be linear. Conversely, if the process requires differencing to be made stationary, then it is called difference stationary and possesses one or more unit roots. Those two concepts may sometimes be confused, but while they share many properties, they are different in many aspects.
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The transceiver head normally contains three or more transducers separated by a baseline of 10 cm or less. A method called “phase-differencing” within this transducer array is used to calculate the direction to the subsea transponder. USBLs have also begun to find use in "inverted" (iUSBL) configurations, with the transceiver mounted on an autonomous underwater vehicle, and the transponder on the target. In this case, the "topside" processing happens inside the vehicle to allow it to locate the transponder for applications such as automatic docking and target tracking.
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The Vista (or later) drive manager GUI supports a subset of the functions in the diskpart command line tool. VHDs known as vdisk in diskpart can be created, formatted, attached (mounted), detached (unmounted), merged (for differencing VHDs), and compacted (for VHDs on an NTFS host file system). Compacting is typically a two step procedure, first unused sectors in the VHD are filled with zeros, . The virtual machine additions in older VPC versions and the virtual machine integration features in Windows Virtual PC contain precompact ISO images for the first step in supported guest systems.
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In early approaches, derivatives in the differential form of the governing transport equation were replaced by finite difference approximations, usually central differencing approximations with second order accuracy. However, for large Peclet numbers (generally > 2) this approximation gave inaccurate results. It was recognized independently by several investigators that the less expensive but only first order accurate upwind scheme can be employed but that this scheme produces results with false diffusion for multidimensional cases. Many new schemes have been developed to counter false diffusion but a reliable, accurate and economical discretisation scheme is still unavailable.
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Numerical solutions use a mesh of the structure to perform the simulation. The most popular methods are: Finite difference time- domain (FDTD) method, Finite element method (FEM) and method of moments (MoM). The finite-difference time-domain (FDTD) method is a robust and popular technique that consists in solving differential equations numerically as well as certain boundary conditions defined by the problem. This is done by discretizing the space and time, and using finite differencing formulas, thus the partial differential equations that describe the physics of the problem can be solved numerically by computer programs.
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Paul de Casteljau (born 1930 in Besançon, France.) is a French physicist and mathematician. In 1959, while working at Citroën, he developed an algorithm for evaluating calculations on a certain family of curves, which would later be formalized and popularized by engineer Pierre Bézier, and the curves called De Casteljau curve or Bézier curves. De Casteljau's algorithm is widely used, with some modifications, as it is the most robust and numerically stable method for evaluating polynomials. Other methods, such as Horner's method and forward differencing, are faster for calculating single points but are less robust.
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Pollock seeks to shift attention from sensationalism toward deeper analysis of Gentileschi's paintings, notably of death and loss, suggesting the significance of her childhood bereavement as a source of her singular images of the dying Cleopatra. Pollock also argues that Gentileschi's success in the seventeenth century depended on her producing paintings for patrons, often portraying subjects they selected that reflected contemporary tastes and fashions. She aims to place Gentileschi's career in its historical context of taste for dramatic narratives of heroines from the Bible or classical sources.Pollock Differencing the Canon: Routledge 1999 Mary Magdalene, c.
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Differencing system in Scottish heraldry For cadets other than immediate heirs, Scottish cadency uses a complex and versatile system, applying different kinds of changes in each generation. First, a bordure is added in a different tincture for each brother. In subsequent generations the bordure may be divided in two tinctures; the edge of the bordure, or of an ordinary in the base coat, may be changed from straight to indented, engrailed or invected; charges may be added. These variations allow the family tree to be expressed clearly and unambiguously.
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In July 1942 Alan Turing spent a few weeks in the Research Section. He had become interested in the problem of breaking Tunny from the keys that had been obtained from depths. In July, he developed a method of deriving the cam settings ("wheel breaking") from a length of key. It became known as "Turingery" (playfully dubbed "Turingismus" by Peter Ericsson, Peter Hilton and Donald Michie) and introduced the important method of "differencing" on which much of the rest of solving Tunny keys in the absence of depths, was based.
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In computational physics, upwind schemes denote a class of numerical discretization methods for solving hyperbolic partial differential equations. Upwind schemes use an adaptive or solution-sensitive finite difference stencil to numerically simulate the direction of propagation of information in a flow field. The upwind schemes attempt to discretize hyperbolic partial differential equations by using differencing biased in the direction determined by the sign of the characteristic speeds. Historically, the origin of upwind methods can be traced back to the work of Courant, Isaacson, and Rees who proposed the CIR method.
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Such models assist in controlling for omitted variable bias due to unobserved heterogeneity when this heterogeneity is constant over time. This heterogeneity can be removed from the data through differencing, for example by subtracting the group-level average over time, or by taking a first difference which will remove any time invariant components of the model. There are two common assumptions made about the individual specific effect: the random effects assumption and the fixed effects assumption. The random effects assumption is that the individual-specific effects are uncorrelated with the independent variables.
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The AIC and the BIC are used for two completely different purposes. While the AIC tries to approximate models towards the reality of the situation, the BIC attempts to find the perfect fit. The BIC approach is often criticized as there never is a perfect fit to real-life complex data; however, it is still a useful method for selection as it penalizes models more heavily for having more parameters than the AIC would. AICc can only be used to compare ARIMA models with the same orders of differencing.
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It also offers an increased image sensor analog signal readout clock rate, reducing rolling shutter. Compared to competitors from Canon (DIGIC, "IPP" compressionMPEG-2MPEG-2 and Video Compression Dr.Dobbs equivalent: Only one previous frame analyzedCanon Tips Off Enhanced Capabilities of Its New Image Processor) the Expeed 2 offers video compression also based on complex B-frames (bi-directional differencing between frames and motion prediction), which has the advantage of higher quality (lower motion blur based on better motion compensation) even with significant higher compression ratio.Nikon D800/D800E: D-Movie shooting functions Nikon This compression requires considerably higher computing power.
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In the former case of a unit root, stochastic shocks have permanent effects, and the process is not mean- reverting. In the latter case of a deterministic trend, the process is called a trend-stationary process, and stochastic shocks have only transitory effects after which the variable tends toward a deterministically evolving (non- constant) mean. A trend stationary process is not strictly stationary, but can easily be transformed into a stationary process by removing the underlying trend, which is solely a function of time. Similarly, processes with one or more unit roots can be made stationary through differencing.
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The arms displays the Curfew tower of Barking Abbey in its crest, this is taken from the old arms of the former Municipal Borough of Barking, granted in 1931. The tower is set before a rising sun, a symbol for progress, which was present in the arms of the former Borough of Dagenham, granted in 1936. The supporters are similar to those of the former Borough of Barking: the lions standing for the Cecil and Monteagle families while the torches represent the main industries from the time of the grant of the old arms, which were gas and electricity. To the 1931 supporters have been added collars for heraldic differencing.
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It was not until the 20th century that advances in the understanding of atmospheric physics led to the foundation of modern numerical weather prediction. In 1922, English scientist Lewis Fry Richardson published "Weather Prediction By Numerical Process",Richardson, Lewis Fry, Weather Prediction by Numerical Process (Cambridge, England: Cambridge University Press, 1922). Available on-line at: Internet Archive.org. after finding notes and derivations he worked on as an ambulance driver in World War I. He described therein how small terms in the prognostic fluid dynamics equations governing atmospheric flow could be neglected, and a finite differencing scheme in time and space could be devised, to allow numerical prediction solutions to be found.
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As well as applying differencing to the full 5-bit characters of the ITA2 code, Tutte applied it to the individual impulses (bits). The current chi wheel cam settings needed to have been established to allow the relevant sequence of characters of the chi wheels to be generated. It was totally impracticable to generate the 22 million characters from all five of the chi wheels, so it was initially limited to 41 × 31 = 1271 from the first two. After explaining his findings to Max Newman, Newman was given the job of developing an automated approach to comparing ciphertext and key to look for departures from randomness.
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The Portuguese system of differentiation for the noble non-Royal families is unlike any other cadency system. It is true that the brisure personalises the arms, however, since the Portuguese have an arbitrary choice of surnames, they may select any family name from the father's or mother's side of their genealogical table and a coat of arms, which does not have to coincide with it. Thus, the system of differencing only serves to show from which ancestral line the arms are derived. The head of the lineage uses the arms without a difference, but should he be the head of more than one family, the arms are combined by quartering.
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To quote the General Report on Tunny: > Turingery introduced the principle that the key differenced at one, now > called ΔΚ, could yield information unobtainable from ordinary key. This Δ > principle was to be the fundamental basis of nearly all statistical methods > of wheel-breaking and setting. Differencing was applied to each of the impulses of the ITA2 coded characters.The five impulses or bits of the coded characters are sometimes referred to as five levels. So, for the first impulse, that was enciphered by wheels \chi1 and \psi1, differenced at one: :::: ΔK1 = K1 ⊕ _K_ 1 And for the second impulse: :::: ΔK2 = K2 ⊕ _K_ 2 And so on.
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SlickEdit, previously known as Visual SlickEdit, is a cross-platform commercial source code editor, text editor, code editor and Integrated Development Environment developed by SlickEdit, Inc. SlickEdit supports Integrated Debuggers for GNU C/C++, Java, WinDbg, Clang C/C++ LLDB, Groovy, Google Go, Python, Perl, Ruby, PHP, Xcode, and Android JVM/NDK. SlickEdit includes such features as built in beautifiers that can beautify code as you type, code navigation, context tagging (also known as Intelligent code completion), symbol references, third party tool integration, DiffZilla (a file differencing tool), syntax highlighting, and over 13 keyboard emulations. In 2014 SlickEdit released a SlickEdit Standard version of their product and renamed their original product SlickEdit Pro.
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False diffusion is a type of error observed when the upwind scheme is used to approximate the convection term in convection–diffusion equations. The more accurate central difference scheme can be used for the convection term, but for grids with cell Peclet number more than 2, the central difference scheme is unstable and the simpler upwind scheme is often used. The resulting error from the upwind differencing scheme has a diffusion-like appearance in two- or three-dimensional co-ordinate systems and is referred as "false diffusion". False-diffusion errors in numerical solutions of convection-diffusion problems, in two- and three-dimensions, arise from the numerical approximations of the convection term in the conservation equations.
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In heraldry, the field (background) of a shield can be divided into more than one area, or subdivision, of different tinctures, usually following the lines of one of the ordinaries and carrying its name (e.g. a shield divided in the shape of a chevron is said to be parted "per chevron"). Shields may be divided this way for differencing (to avoid conflict with otherwise similar coats of arms) or for purposes of marshalling (combining two or more coats of arms into one), or simply for style. The lines that divide a shield may not always be straight, and there is a system of terminology for describing patterned lines, which is also shared with the heraldic ordinaries.
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Whereas a first order upwind scheme smears the interface, a downwind scheme of the same order will cause a false distribution problem which will cause erratic behavior in case of the flow is not oriented along a grid line. As these lower-order schemes are inaccurate, and higher-order schemes are unstable and induce oscillations, it has been necessary to develop schemes which keep the free-surface sharp while also producing monotonic profiles for C. Over the years, a multitude of different methods for treating the advection have been developed. In the original VOF-article by Hirt, a donor-acceptor scheme was employed. This scheme formed a basis for the compressive differencing schemes.
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Roberts was the co- author of many influential publications, including two groundbreaking books: Basic Methods of Marketing Research (with James Lorie) and the textbook, Statistics: A New Approach (with W. Allen Wallis). He also co-authored an early work on the random walk hypothesis of stock market prices, “Differencing of Random Walks and Near Random Walks,” with Nicholas Gonedes, published in the Journal of Econometrics in 1977. Roberts was an early computer enthusiast, and was especially interested in developing computer methods for statistical analysis. In the late 1960s, Roberts, in collaboration with his wife June and Robert Ling, developed a statistics package called Interactive Data Analysis (IDA), used for statistical instruction at a number of top business schools.
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Second, the direct emission from a planet atmosphere may be detected by differencing the star plus planet light obtained during most of the planet's orbit with the light of just the star during secondary eclipse (when the exoplanet is behind its star). The first observed extrasolar planetary atmosphere was made in 2001. Sodium in the atmosphere of the planet HD 209458 b was detected during a set of four transits of the planet across its star. Later observations with the Hubble Space Telescope showed an enormous ellipsoidal envelope of hydrogen, carbon and oxygen around the planet. This envelope reaches temperatures of 10,000 K. The planet is estimated to be losing (1-5)×108 kg of hydrogen per second.
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In order to find the cell face value a quadratic function passing through two bracketing or surrounding nodes and one node on the upstream side must be used. In central differencing scheme and second order upwind scheme the first order derivative is included and the second order derivative is ignored. These schemes are therefore considered second order accurate where as QUICK does take the second order derivative into account, but ignores the third order derivative hence this is considered third order accurate. This scheme is used to solve convection–diffusion equations using second order central difference for the diffusion term and for the convection term the scheme is third order accurate in space and first order accurate in time.
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The original model uses an iterative three-stage modeling approach: #Model identification and model selection: making sure that the variables are stationary, identifying seasonality in the dependent series (seasonally differencing it if necessary), and using plots of the autocorrelation (ACF) and partial autocorrelation (PACF) functions of the dependent time series to decide which (if any) autoregressive or moving average component should be used in the model. #Parameter estimation using computation algorithms to arrive at coefficients that best fit the selected ARIMA model. The most common methods use maximum likelihood estimation or non-linear least-squares estimation. #Statistical model checking by testing whether the estimated model conforms to the specifications of a stationary univariate process.
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Label on an escutcheon In European heraldry in general, the label was used to mark the elder son, generally by the princes of the royal house. Differencing, or cadency, are the distinctions used to indicate the junior branches (cadets) of a family. In British heraldry, a system of specific brisures or "marks of cadency" developed: The eldest son, during the lifetime of his father, bears the family arms with the addition of a label; the second son a crescent, the third, a mullet, the fourth, a martlet, the fifth, an annulet; the sixth, a fleur-de-lis; the seventh, a rose; the eighth, a cross moline; the ninth, a double quatrefoil. On the death of his father, the eldest son would remove the label from his coat of arms and assume the unmodified arms.
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Alan Turing discovered this weakness and invented the differencing technique described below to exploit it. The pattern of which of the cams were in the raised position, and which in the lowered position was changed daily on the motor wheels (\mu37 and \mu61). The chi wheel cam patterns were initially changed monthly. The psi wheel patterns were changed quarterly until October 1942 when the frequency was increased to monthly, and then to daily on 1 August 1944, when the frequency of changing the chi wheel patterns was also changed to daily. The number of start positions of the wheels was 43×47×51×53×59×37×61×41×31×29×26×23 which is approximately 1.6×1019 (16 billion billion), far too large a number for cryptanalysts to try an exhaustive "brute-force attack".
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Adjusting for serial correlation is the purpose of moving standard deviations, which use deviations from the moving average, but the possibility remains of high order price autocorrelation not accounted for by simple differencing from the moving average. For such reasons, it is incorrect to assume that the long-term percentage of the data that will be observed in the future outside the Bollinger Bands range will always be constrained to a certain amount. Instead of finding about 95% of the data inside the bands, as would be the expectation with the default parameters if the data were normally distributed, studies have found that only about 88% of security prices (85–90%) remain within the bands. For an individual security, one can always find factors for which certain percentages of data are contained by the factor defined bands for a certain period of time.
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While the degree to which the general law recognises arms differs, in both England and Scotland a grant of arms confers certain rights upon the grantee and his (or her) heirs, even if they may not be easily protected. No person may lawfully have the same coat of arms as another person in the same heraldic jurisdiction although in England the bearing of identical arms without differencing marks by descendants from a common armigerous ancestor has been widespread and tolerated by the College of Arms. Although the common law courts do not regard coats of arms as either property or as being defensible by action, armorial bearings are a form of property nevertheless, generally described as tesserae gentilitatis or insignia of gentility. Armorial bearings are incorporeal and impartible hereditaments, inalienable, and descendable according to the law of arms.
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On one of these is the inscription: "VIVENTES / CARDILIUM / ETAVITAM / FELIXTURRE", while on another is a figure of a Roman couple, circled by craters, a sickle, birds, diametrically opposed 2x2 posts and with flowers in the corners. The inscription of the Roman property owners has had differencing interpretations, that included: "Felix of Turre created the mosaics in homage to Cardílio and Avita";Paço (1963) "Felix created the picture of Cardílio and Avita, in life, in the locality called Turris";Lambrino (1963) "Torre was happy while Cardílio and Avita lived";Garcia y Bellido in Paço (1964) "Cardílio and Avita lived here in the happy tower"Cerejo (1980) The objects in the property-owner's panel, the sickle and the craters, may have represented the cultivation of wheat and vineyard.Costa (1982), p. 48 There also exist vestiges of a "frigidarium" (cold baths), "caldarium" (hot baths) and respective "hypocaustum", as well as a pool, to the west of the"peristylum".
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The white clouds of the full-color President's flag on the white background would give a similar effect. The Secretary of the Navy's flag is blue with a white anchor and stars on it; the flag of the Assistant Secretary of the Navy uses the same design with the colors reversed (blue stars and anchor on a white background). The same concept was used for the Vice President's flag, and has since become the standard system in the U.S. Government for differencing the flags of the first and second ranking civilian officials in any hierarchy, In 1940, an Undersecretary of the Navy position was created below the Secretary but above the Assistant, whose flag is a white anchor and stars on a red background. and would be repeated on all subsequent vice presidential flags. The USS Colorado, where the unofficial Vice President's flag was raised during the 1915 ceremony Vice President Marshall arrived at the Exposition on March 20, 1915.
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Calder In heraldry, cabossed, or caboched, is a term used where the head of a beast is cut off behind the ears, by a section parallel to the face; or by a perpendicular section: in contrast to couping, which is done by a horizontal line, and farther from the ears than cabossing.Chambers, Ephraim, 1680 (ca.)-1740. Cyclopædia, or, An universal dictionary of arts and sciences .... History of Science and Technology, in University of Wisconsin Digital Collections In other words, heads may appear cabossed (also caboshed or caboched): with the head cleanly separated from the neck so that only the face shows; couped: with the neck cleanly separated from the body so that the whole head and neck are present; or erased: with the neck showing a ragged edge as if forcibly torn from the body. While cabossed heads are shown facing forward (affronté), heads that are couped or erased face dexter unless otherwise specified for differencing.
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In this case the stochastic term is stationary and hence there is no stochastic drift, though the time series itself may drift with no fixed long-run mean due to the deterministic component f(t) not having a fixed long-run mean. This non-stochastic drift can be removed from the data by regressing y_t on t using a functional form coinciding with that of f, and retaining the stationary residuals. In contrast, a unit root (difference stationary) process evolves according to :y_t = y_{t-1} + c + u_t where u_t is a zero-long-run-mean stationary random variable; here c is a non-stochastic drift parameter: even in the absence of the random shocks ut, the mean of y would change by c per period. In this case the non-stationarity can be removed from the data by first differencing, and the differenced variable z_t = y_t - y_{t-1} will have a long-run mean of c and hence no drift.
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There are also forward differencing methods, but great care must be taken to analyse error propagation. Analytical methods where a Bézier is intersected with each scan line involve finding roots of cubic polynomials (for cubic Béziers) and dealing with multiple roots, so they are not often used in practice. The rasterisation algorithm used in Metafont is based on discretising the curve, so that it is approximated by a sequence of "rook moves" that are purely vertical or purely horizontal, along the pixel boundaries. To that end, the plane is first split into eight 45° sectors (by the coordinate axes and the two lines y = \pm x ), then the curve is decomposed into smaller segments such that the direction of a curve segment stays within one sector; since the curve velocity is a second degree polynomial, finding the t values where it is parallel to one of these lines can be done by solving quadratic equations.
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But even in the absence of the parameter c (that is, even if c=0), this unit root process exhibits drift, and specifically stochastic drift, due to the presence of the stationary random shocks ut: a once- occurring non-zero value of u is incorporated into the same period's y, which one period later becomes the one-period-lagged value of y and hence affects the new period's y value, which itself in the next period becomes the lagged y and affects the next y value, and so forth forever. So after the initial shock hits y, its value is incorporated forever into the mean of y, so we have stochastic drift. Again this drift can be removed by first differencing y to obtain z which does not drift. In the context of monetary policy, one policy question is whether a central bank should attempt to achieve a fixed growth rate of the price level from its current level in each time period, or whether to target a return of the price level to a predetermined growth path.
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So this is essentially similar to one of the classical Laplacian receptive fields for square arrays - that with weightings of -1 on each side and -0.5 on each corner. The only difference is an aspect ratio of 8:7.07 (or approximately 8:7 to within 1%). Very useful further evidence of the processes going on in his area comes from the electron-microscopy studies of Kolb Organization of the outer plexiform layer of the primate retina: electron microscopy of Golgi-impregnated sells by H. Kolb Philosophical Transactions of the Royal Society Lond B, Soc Lond B Volume 258 page 261 1970 These clearly show the neural structures which lead to difference signals being transmitted further. If one combines a point spread function having a Gaussian form and having an S.D. of 1.3 'pixels' with a single ring Laplacian - type operator, the resultant is a function with very similar properties to a DOG function as discussed by Marr.Vision by David Marr Published by Freeman, San Francisco 1988 It is normally assumed, both in computer image processing and in visual science, that a local excitatory / inhibitory process is effectively a second differencing process.
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The relationship amongst these elements still applies when they are differenced. For example, as well as: :::: K = \chi ⊕ \psi It is the case that: :::: ΔK = Δ\chi ⊕ Δ\psi Similarly for the ciphertext, plaintext and key components: :::: ΔZ = ΔP ⊕ Δ\chi ⊕ Δ\psi So: :::: ΔP = ΔZ ⊕ Δ\chi ⊕ Δ\psi The reason that differencing provided a way into Tunny, was that although the frequency distribution of characters in the ciphertext could not be distinguished from a random stream, the same was not true for a version of the ciphertext from which the chi element of the key had been removed. This is because, where the plaintext contained a repeated character and the psi wheels did not move on, the differenced psi character (Δ\psi) would be the null character ('/' at Bletchley Park). When XOR-ed with any character, this character has no effect, so in these circumstances, The ciphertext modified by the removal of the chi component of the key was called the de-chi D at Bletchley Park, refers to the de-chi as being "pseudo plain" and the process of removing it as "de-chi-ing".
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Feminist Germaine Greer points out in her chapter on Artemisia in her book on women painters, The Obstacle Race, that the rape trial transcripts are not transparent, and that there is evidence that supports Merlet's construction. The rape trial records may be found in an appendix to Garrard's book. Garrard interprets them one way (Artemisia was raped, didn't love Tassi); Greer interprets them differently (Artemisia was raped, but came to love her rapist); Merlet offers a third interpretation (Artemisia loved her rapist from the start). Garrard's account was savaged by a number of feminist reviewers, and most recently challenged by Griselda Pollock in Differencing the Canon: > Merlet's film is, I would argue, not really a biography, for there is no > analysis of the impact of the early death of the artist's mother and her > bereavement, no exploration of how she made a massively successful career in > Italy and beyond after the horrors of the trial and her torture, how she > married and mothered several daughters who also became artists, how she > negotiated with some of the major patrons of her time for the commissions on > which she lived and through which she, not their father, accumulated dowries > for her daughter.
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