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Space-scale analysis

C. Space-Scale Analysis Based on Continuous Wavelet Transform Low-Frequency Rhythms in Human DNA Sequences... [Pg.203]

The continuous wavelet transform (WT) is a space-scale analysis that consists in expanding signals in terms of wavelets that are constructed from a single function, the analyzing wavelet /, by means of dilations and translations [13, 27-29]. When using the successive derivatives of the Gaussian function as analyzing wavelets, namely... [Pg.209]

Discriminant emalysis is a supervised learning technique which uses classified dependent data. Here, the dependent data (y values) are not on a continuous scale but are divided into distinct classes. There are often just two classes (e.g. active/inactive soluble/not soluble yes/no), but more than two is also possible (e.g. high/medium/low 1/2/3/4). The simplest situation involves two variables and two classes, and the aim is to find a straight line that best separates the data into its classes (Figure 12.37). With more than two variables, the line becomes a hyperplane in the multidimensional variable space. Discriminant analysis is characterised by a discriminant function, which in the particular case of hnear discriminant analysis (the most popular variant) is written as a linear combination of the independent variables ... [Pg.719]

Several methods are available in the literature for the measurement of aliphatic amines in biological samples [28]. Problems with specificity and separation and cumbersome derivatisation and/or extraction procedures have limited the use of these techniques on a larger scale in clinical practice. The lack of a simple analytical method may have led to an underestimation of the incidence of the fish odour syndrome. For diagnosing the syndrome, an analytical technique should be used that is able to simultaneously and quantitatively measure TMA and its N-oxide in the complex matrix of human urine. Two such methods are currently available for this purpose proton nuclear magnetic resonance (NMR) spectroscopy and head-space gas analysis with gas chromatography or direct mass spectrometry (see below). [Pg.784]

Finite difference — Finite difference is an iterative numerical procedure that has been used to quantify current-voltage-time relationships for numerous electrochemical systems whose analyses have resisted analytic solution [i]. There are two generic classes of finite difference analysis 1. explicit finite difference (EFD), where a new set of parameters at t + At is computed based on the known values of the relevant parameters at t and 2. implicit finite difference (IFD), where a new set of parameters at t + At is computed based on the known values of the relevant parameters at t and on the yet-to-be-determined values at t + At. EFD is simple to encode and adequate for the solution of many problems of interest. IFD is somewhat more complicated to encode but the resulting codes are dramatically more efficient and more accurate - IFD is particularly applicable to the solution of stiff problems which involve a wide dynamic range of space scales and/or time scales. [Pg.273]

Aluko. M., and H.-C. Chang. Multi-scale analysis of exotic dynamics in surface catalyzed reactions-II. Quantitative parameter space analysis of an extended Langmuir-Hinshelwood reaction scheme, Chem. Eng. ScL, 39, 51-64 (1984). [Pg.29]

In order to provide an easy way to visualize how the methods differ from each other the accuracy values (Q3, Ca, Cp and Cc) for each method where subjected to nonmetric multidimensional scaling analysis (Cox and Cox, 1994). The resulting graphs provide a representation in a two-dimensional space of the methods and those are shown in figure 3. As can be observed, the interrelationship between the methods... [Pg.791]

Finally, we add rate parameters to the scaling analysis. Up to this point the fact that time has dimension has been ignored, since the scaling approach predicts only exponents, not rates. In the strongly delocalized limit the relevant rate is the coefficient of diffusion D in quantum number space. Thus in this limit,... [Pg.132]

The model we have chosen is expected to exhibit dynamical scaling since it is a local random matrix model. It satisfies the assumption of an isotropic statistically homogeneous state-space used in deriving the results of Section III. Since there are six modes, the dynamics occur on the five-dimensional constant-energy surface in quantum number space. Therefore the scaling analysis gives... [Pg.139]

Abstract As a non-invasive technique, NMR spectroscopy allows the observation of molecular transport in porous media without any disturbance of their intrinsic molecular dynamics. The space scale of the diffusion phenomena accessible by NMR ranges from the elementary steps (as studied, e.g., by line-shape analysis or relaxometry) up to macroscopic dimensions. Being able to follow molecular diffusion paths from ca. 100 nm up to ca. 100 xm, PPG NMR has proven to be a particularly versatile tool for diffusion studies in heterogeneous systems. With respect to zeolites, PFG NMR is able to provide direct information about the rate of molecular migration in the intracrystalline space and through assemblages of zeolite crystallites as well as about possible transport resistances on the outer surface of the crystallites (surface barriers). [Pg.85]

Atmospheric motions are observed on nearly all scales of time and space. To understand these motions, it is necessary to determine which terms in the physical equations are most important in governing the behavior of a particular phenomenon on a partioular time and space scale. If possible, the equations are sealed to isolate a single type or class of motions. Analysis of these reduced sets of equations provides insight into the fundamental dynamics of a given type of motion. Appheation of the linearization technique helps to isolate these seales. [Pg.237]

A set of limiting cases of transport is developed, comprising of situations where diffusion through the void space, fiber space and external boundary layers, each contribute significantly to transport. By means of a scaling analysis, the conditions under which each limiting case is valid are identified. Finally, a comparison of the model predictions with experimental data indicates that the model is capable of describing transient sorption dynamics quite well. [Pg.531]

Because moments are extensive, non-local, objects, their use in quantizing the energy and wavefunction will implicitly be of a multiscale nature, proceeding from large through small scales, as more moments are used. In addition, since moments transform linearly under affine maps, any moment based analysis will incorporate some degree of space-scale invariance, which can be an efficient feature for quantizing systems. [Pg.214]

The last chapter of the volume, contributed by Carlos R. Han%, is devoted to recent developments in the incorporation of Continuous Wavelet Transform analysis into quantum operator theory. The focus is to combine generalized, scale translation-dependent moments to facihtate the quantum problem into an extended space-scale parameter representatiem. The proposed approach yields a new quantization theory suited to the scalet-wavelet formalism. [Pg.276]

This constitutes the simplest GLE [88, 89], Until now we have not specified explicitly the new spatial scaling. By appropriate scaling the time, length, and A all parameters can he scaled away. Note that the conventional way to derive the GLE starts from a multi-scale analysis in space and time, expanding systematically in powers of... [Pg.274]


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Analysis spacing

Continuous wavelet transform space-scale analysis

Scaling analysis

Space scales

Space-scale analysis transform

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