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Data analysis behavior

A good model is consistent with physical phenomena (i.e., 01 has a physically plausible form) and reduces crresidual to experimental error using as few adjustable parameters as possible. There is a philosophical principle known as Occam s razor that is particularly appropriate to statistical data analysis when two theories can explain the data, the simpler theory is preferred. In complex reactions, particularly heterogeneous reactions, several models may fit the data equally well. As seen in Section 5.1 on the various forms of Arrhenius temperature dependence, it is usually impossible to distinguish between mechanisms based on goodness of fit. The choice of the simplest form of Arrhenius behavior (m = 0) is based on Occam s razor. [Pg.212]

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]

Creep behavior, determining, 13 474-477 Creep curve, 21 742 analysis of, 13 472 Creep data analysis, 13 477-480 Creep deformation, 13 470, 471—480 effects of temperature and stress on, 13 474... [Pg.231]

The major disadvantage associated with the discontinuous approach is that only a single measurement is made, facilitating data analysis. The discontinuous approach is perfectly acceptable if all the necessary preliminary experiments have been completed. But, as is evident too often in the literature, they have not been done, and because the data output from such experiments does not permit visualization of the enzyme s behavior throughout the incubation period, the researcher remains blissfully unaware that any problem exists. [Pg.100]

This article reviews the following solution properties of liquid-crystalline stiff-chain polymers (1) osmotic pressure and osmotic compressibility, (2) phase behavior involving liquid crystal phasefs), (3) orientational order parameter, (4) translational and rotational diffusion coefficients, (5) zero-shear viscosity, and (6) rheological behavior in the liquid crystal state. Among the related theories, the scaled particle theory is chosen to compare with experimental results for properties (1H3), the fuzzy cylinder model theory for properties (4) and (5), and Doi s theory for property (6). In most cases the agreement between experiment and theory is satisfactory, enabling one to predict solution properties from basic molecular parameters. Procedures for data analysis are described in detail. [Pg.85]

Ref A.M. Weston L.G. Green, Data Analysis of the Reaction Behavior of Explosive Materials Subjected to Susan Test Impacts , UCRL-13480, Lawrence Livermore Lab, Univ of Calif (1970)... [Pg.483]

Chapters 3 and 4, by Orfanopoulos and Lissi et al., emphasize different aspects of the excited-state behavior of 102. An in-depth and critical review of the reaction of 02 with alkenes provided by Orfanopoulos should be of significant value to newcomers and current practitioners of 02 chemistry. Lissi et al. summarize results of the photophysical behavior of 02 in various solvents and organized assemblies. The extensive data analysis will be of interest to both photochemists and photobiologists. [Pg.763]

A key factor in modeling is parameter estimation. One usually needs to fit the established model to experimental data in order to estimate the parameters of the model both for simulation and control. However, a task so common in a classical system is quite difficult in a chaotic one. The sensitivity of the system s behavior to the initial conditions and the control parameters makes it very hard to assess the parameters using tools such as least squares fitting. However, efforts have been made to deal with this problem [38]. For nonlinear data analysis, a combination of statistical and mathematical tests on the data to discern inner relationships among the data points (determinism vs. randomness), periodicity, quasiperiodicity, and chaos are used. These tests are in fact nonparametric indices. They do not reveal functional relationships, but rather directly calculate process features from time-series records. For example, the calculation of the dimensionality of a time series, which results from the phase space reconstruction procedure, as well as the Lyapunov exponent are such nonparametric indices. Some others are also commonly used ... [Pg.53]

Erlang- and phase-type distributions provide a versatile class of distributions, and are shown to fit naturally into a Markovian compartmental system, where particles move between a series of compartments, so that phase-type compartmental retention-time distributions can be incorporated simply by increasing the size of the system. This class of distributions is sufficiently rich to allow for a wide range of behaviors, and at the same time offers computational convenience for data analysis. Such distributions have been used extensively in theoretical studies (e.g., [366]), because of their range of behavior, as well as in experimental work (e.g., [367]). Especially for compartmental models, the phase-type distributions were used by Faddy [364] and Matis [301,306] as examples of long-tailed distributions with high coefficients of variation. [Pg.231]

A solution to this hurdle was first given by genomics, when several genome-wide techniques such as transcriptome and metabolome analysis started to be routinely applied on microbial systems. These techniques, besides requiring significant expertise in data analysis [217], allow the extraction of a vast quantity of information. Unfortunately, the sole presence of this wealth of data is not sufficient to understand the cell behavior from a holistic perspective. To address this issue,... [Pg.82]

For positrons and Ps in polymeric surfaces, one needs to consider three additional important effects in addition to the bulk (1) the diffusion of the positron and Ps back to the surface, (2) the formation of Ps from the positrons by abstracting the surface electron, and (3) the Ps emission to the vacuum from the surface or the sticking of Ps on the polymeric surfaces. The dynamic behavior of the positron and Ps near the surface is schematically shown in Figure 11.2 below. The lifetimes of the positron and of Ps are different among those three types in addition to that of the bulk. If each has one distinct lifetime, a typical PAL lifetime spectrum could contain eight lifetimes for a complete analysis. This is beyond the current resolving power of the PAL data analysis method, either discrete or continuous. A practical approach is to invoke some good theoretical models before one applies the conventional data analysis method to a PAL spectrum near the surface for polymeric materials. [Pg.285]


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See also in sourсe #XX -- [ Pg.316 ]

See also in sourсe #XX -- [ Pg.316 ]




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