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Integrating functions

The finite element solution of differential equations requires function integration over element domains. Evaluation of integrals over elemental domains by analytical methods can be tedious and impractical and is not attempted in... [Pg.38]

L joc ( ) space of functions, integrable with square in any compact sub-domain of... [Pg.373]

Electron Beam Techniques. One of the most powerful tools in VLSI technology is the scanning electron microscope (sem) (see Microscopy). A sem is typically used in three modes secondary electron detection, back-scattered electron detection, and x-ray fluorescence (xrf). AH three techniques can be used for nondestmctive analysis of a VLSI wafer, where the sample does not have to be destroyed for sample preparation or by analysis, if the sem is equipped to accept large wafer-sized samples and the electron beam is used at low (ca 1 keV) energy to preserve the functional integrity of the circuitry. Samples that do not diffuse the charge produced by the electron beam, such as insulators, require special sample preparation. [Pg.356]

Using these assumptions and a classical partitioning function, integrated over the coordinates and momenta of aH molecules, a universal function was defined ... [Pg.239]

The thermodynamic quantities and correlation functions can be obtained from Eq. (1) by functional integration. However, the functional integration cannot usually be performed exactly. One has to use approximate methods to evaluate the functional integral. The one most often used is the mean-field approximation, in which the integral is replaced with the maximum of the integrand, i.e., one has to find the minimum of. F[(/)(r)], which satisfies the mean-field equation... [Pg.692]

Let us underline some similarities and differences between a field theory (FT) and a density functional theory (DFT). First, note that for either FT or DFT the standard microscopic-level Hamiltonian is not the relevant quantity. The DFT is based on the existence of a unique functional of ionic densities H[p+(F), p (F)] such that the grand potential Q, of the studied system is the minimum value of the functional Q relative to any variation of the densities, and then the trial density distributions for which the minimum is achieved are the average equihbrium distributions. Only some schemes of approximations exist in order to determine Q. In contrast to FT no functional integrations are involved in the calculations. In FT we construct the effective Hamiltonian p f)] which never reduces to a thermo-... [Pg.807]

If the coefficients dy vanish, dy = 28y, we recover the exact Debye-Huckel limiting law and its dependence on the power 3/2 of the ionic densities. This non-analytic behavior is the result of the functional integration which introduces a sophisticated coupling between the ideal entropy and the coulomb interaction. In this case the conditions (33) and (34) are verified and the... [Pg.814]

Perhaps the most rigorous way of dividing a molecular volume into atomic subspaces is the Atoms In Molecules (AIM) method of Bader.The electron density is the square of the wave function integrated over N — coordinates (it does not matter which coordinates since all electrons are identical). [Pg.223]

In wave mechanics the electron density is given by the square of the wave function integrated over — 1 electron coordinates, and the wave function is determined by solving the Schrddinger equation. For a system of M nuclei and N electrons, the electronic Hamilton operator contains the following tenns. [Pg.408]

Appetite control is a complex function of the brain that regulates feeding behaviour. This function integrates cognitive and emotional factors with a complex array of signals from the gastrointestinal tract and from adipose tissue. [Pg.209]

Material flowing at a position less than r has a residence time less than t because the velocity will be higher closer to the centerline. Thus, F(r) = F t) gives the fraction of material leaving the reactor with a residence time less that t where Equation (15.31) relates to r to t. F i) satisfies the definition. Equation (15.3), of a cumulative distribution function. Integrate Equation (15.30) to get F r). Then solve Equation (15.31) for r and substitute the result to replace r with t. When the velocity profile is parabolic, the equations become... [Pg.556]

The drying protoplast will be subjected to tension as the result of volume contraction and its adherence to the cell wall. Early observations (Steinbrick, 1900) on desiccation tolerant species showed that the protoplasm does not separate from the wall, but rather that it folds and cavities develop in the wall. Where there are thick-walled cells, localised separation of the plasmalemma from the wall may occur. It seems unlikely, however, that rupture of the plasmalemma normally occurs during desiccation. A more subtle form of membrane damage may arise from dehydration-induced conformational changes. Certainly it is relatively easy to demonstrate that dehydrated membranes exhibit a loss of functional integrity... [Pg.117]

In the case of filled rubbers, the network is represented by a huge chain of contour length L = NL, where N is the number of primary chains of length L. The observable (macroscopic) free energy is given by Equation 22.9, where Z(n) is the replicated partition function that is estimated by functional integration over the continuous chain conformations ... [Pg.610]

Imayoshi I, Sakamoto M, Ohtsuka T, Takao K, Miyakawa T, Yamaguchi M, Moii K, Ikeda T, Itohara S, Kageyama R (2008) Roles of continuous neurogenesis in the structural and functional integrity of the adult forebrain. Nat Neurosci 11 1153-1161 Imitola J (2007) Prospects for neural stem ceU-based therapies for neurological diseases. Neurotherapeutics 4 701-714... [Pg.215]

Concerning function integration, for example, micro-flow membrane reactors can exhibit similar process intensification, as shown already for their large-scale counterparts [75]. Separation columns for proteomics, immobilizing enzymes, utilize the large surface-to-volume ratios. Surface tension differences can guide and transport liquids selectively. [Pg.51]

The energy due to the external potential is determined simply by the density and is therefore independent of the wave function generating that density. Hence, it is the same for all wave functions integrating to a particular density and we can separate it from the kinetic and electron-electron repulsion contributions... [Pg.55]

If any one of these integrals (expectation value equations) is zero, the transition is said to be forbidden. For the electronic and spin wave functions, it is not necessary to evaluate the integral but only to note that an odd function integrated from minus infinity to infinity is zero, while an even function integrated within these limits results in a nonzero value. For example (Figure 2.1),... [Pg.317]

Polarization fluctuations of a certain type were considered in the configuration model presented above. In principle, fluctuations of a more complicated form may be considered in the same way. A more general approach was suggested in Refs. 23 and 24, where Eq. (16) for the transition probability has been written in a mixed representation using the Feynman path integrals for the nuclear subsystem and the functional integrals over the electron wave functions of the initial and final states t) and t) for the electron ... [Pg.117]

A sequence of approximations, using properties of the confluent hypergeometric function, integration by steepest descents, and judicious discard of all but the dominant terms, gives one the asymptotic form... [Pg.255]

The structural and functional integrity of organoclay-wrapped Mb and Hb molecules was demonstrated by retention of the secondary protein structure as well as distinctive shifts in the absorption spectra associated with oxygen or carbon monoxide binding to the heme metallocenter. The latter indicated that the wrapped... [Pg.255]


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See also in sourсe #XX -- [ Pg.60 , Pg.61 , Pg.62 , Pg.63 , Pg.64 , Pg.65 ]




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