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Numerical manipulation

As discussed and illustrated in the introduction, data analysis can be conveniently viewed in terms of two categories of numeric-numeric manipulation, input and input-output, both of which transform numeric data into more valuable forms of numeric data. Input manipulations map from input data without knowledge of the output variables, generally to transform the input data to a more convenient representation that has unnecessary information removed while retaining the essential information. As presented in Section IV, input-output manipulations relate input variables to numeric output variables for the purpose of predictive modeling and may include an implicit or explicit input transformation step for reducing input dimensionality. When applied to data interpretation, the primary emphasis of input and input-output manipulation is on feature extraction, driving extracted features from the process data toward useful numeric information on plant behaviors. [Pg.43]

Because the term r(CA T) is exponentially dependent on T and can be nonlinear as well, a numerical solution or piecewise linearization must be used. To simplify the numerical manipulations, equations in Table IX are normalized by = z/L, r = ut/L, and jc = 1 - C,/(C,)0, where i is normally S02. y also is a normalized quantity. The Peclet numbers for mass and heat are written PeM = 2Rpu/D) and PeH = 2Rpcpul t for a spherical particle. They are also written in terms of bed length as Bodenstein numbers. It is... [Pg.234]

In experimental kinetics studies one measures (directly, or indirectly) the concentration of one or more of the reactant and/or product species as a function of time. If these concentrations are plotted against time, smooth curves should be obtained. For constant volume systems the reaction rate may be obtained by graphical or numerical differentiation of the data. For variable volume systems, additional numerical manipulations are necessary, but the process of determining the reaction rate still involves differentiation of some form of the data. For example,... [Pg.41]

So, sensitivity is obviously quite good despite the numerous manipulations required to produce an amplifiable sample, but what about the specificity One of the problems in any PCR reaction is the appearance of extra bands caused by false... [Pg.371]

In addition, there is a need for maximizing process understanding while consuming the minimum amount of material due to the value (and frequently limited supply) of the materials themselves. Many of the synthetic processes involve numerous reaction steps and numerous manipulations, so it is common for the supply of material to be the limiting factor to the number of experiments that can be performed, making the information content of each experiment of paramount importance. [Pg.333]

The strength of the bioassay approach is that it directly estimates the fraction of natural DOC that can be used by a natural microbial assemblage under defined conditions. However, there are numerous manipulations of water samples during bioassay incubations, and the effects of these manipulations on the measured parameters are not well known. For example, containment of water samples can rapidly alter microbial population structure. Nutrients, rather than carbon, can be limiting for microbial utilization of DOM. Moreover, there are no standard protocols for bioassay experiments. Different indicators of DOM utilization are measured by different investigators, and many of the measured parameters rely on conversion factors that are also quite variable. The extent of DOM utilization also depends upon the duration and temperature of the bioassay experiment. Despite these shortcomings, the bioassay experiment remains the best approach for estimating the bioavailability of DOM. [Pg.128]

Problems are included at the end of each chapter. Some of these problems are of a routine nature to familiarize the student with the numerical manipulations and orders of magnitude of various parameters which occur in the subject of heat transfer. Other problems extend the subject matter by requiring students to apply the basic principles to new situations and develop their own equations. Both types of problems are important. [Pg.695]

Routine applications of the refrigerated immersion probe bath include low temperature synthesis, collection flask cooling (for low pressure distillations), and numerous manipulations involving... [Pg.147]

Data Processing. The above are superficial benefits of modem electronics. Of even greater value is the electronic processing of the raw data. A read-out directly proportional to concentration can easily be produced, although this requires a logarithmic conversion for colorimetric or spectrophotometric systems. If the instrument is calibrated with a standard of known concentration, the read-out can also be made directly in reportable units. This is a major time saver and, in addition, reduces errors in numerical manipulation and transcription. [Pg.793]

An evaluation of the utility of these multimedia models has noted that they provide an effective mechanism of ranking chemicals, both new and existing. The environmental data derived from the models can provide a basis for developing a first-cut risk assessment and baselines for assessing the risk from hazardous waste sites. Since the data input is not overwhelming and the numerical manipulations straightforward, the models provide a cheap and rapid way to evaluate the... [Pg.383]

Check The piocedure must be correct because we obtained the correct net equation. In cases like this you should go back over the numerical manipulations of the AH t ues to ensure that you did not make an inadvertent error with signs. [Pg.183]

There are different reasons for the numerical manipulation of data. One of these is data reduction others are filtering and smoothing, magnification of the amplitude of the spectra or of certain spectral features, and standardization. After the preceding computations, different algorithms for digital differentiation can be applied. [Pg.73]

As physical observables they have a special status in the quantum theory. They are not related to specific levels of approximation of the theory, nor to special or specific numerical manipulations of quantities defined only for a given approximation. [Pg.231]

The use of dimensionless groups and the need for numerical manipulation of the equations solved for has been considerably reduced over the recent years, due to the use of sophisticated software capable of integrating computational... [Pg.638]

Checking for the ULS in a deformation-related model is normally performed by reducing the shear strength in small iterative steps until large deformations occur in the model. This may, however, lead to numerical problems with the FEM and requires numerical manipulation to allow for such calculations. [Pg.227]

The system of algebraic equations of a multi-dimensional problem can be assembled on the conventional form (12.401), which simplifies the numerical manipulation. In this approach, the numerical solution approximation is expressed by a global index numbering procedure. [Pg.1219]

That is, the determinate of a product is the product of determinates. This property is useful when finding the determinate of a matrix by numerical manipulations. [Pg.62]

Matrix notation and matrix manipulation is not used extensively in this book. However, there are a few cases where being able to numerically manipulate matrices is very useful. One such case will be encountered in a subsequent chapter on solving coupled differential equations. [Pg.131]


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See also in sourсe #XX -- [ Pg.73 ]




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Numerical Manipulation of Digitized Curves

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