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Invoking evaluation functions

We impose no restriction on evaluation functions (including the function which displays entities) other than that they should not modify the present model. Graphical rendering of information is considered as one of the typical evaluation functions. [Pg.41]


CHEOPS obtains this setup file in XML format from ModKit-l-. Tool wrappers are started according to this XML file. The input files required for the modeling tools Aspen Plus and gPROMS are obtained from the model repository ROME. CHEOPS applies a sequential-modular simulation strategy implemented as a solver component because all tool wrappers are able to provide closed-form model representations. The iterative solution process invokes the model evaluation functionality of each model representation, which refers to the underljdng tool wrapper to invoke the native computation in the modeling tool the model originated from. Finally, the results of all stream variables are written to a Microsoft Excel table when the simulation has terminated. [Pg.491]

This last point suggests an alternative interpretation of the transport coefficient as the one corresponding to the correlation function evaluated at the point of maximum flux. The second entropy is maximized to find the optimum flux at each x. Since the maximum value of the second entropy is the first entropy sM(x), which is independent of x, one has no further variational principle to invoke based on the second entropy. However, one may assert that the optimal time interval is the one that maximizes the rate of production of the otherwise unconstrained first entropy, 5(x (x, x), x) = x (x,x) Xs(x), since the latter is a function of the optimized fluxes that depend on x. [Pg.26]

Scatter search has been implemented in software called OPTQUEST (see www.opttek.com). OPTQUEST is available as a callable library written in C, which can be invoked from any C program, or as a dynamic linked library (DLL), which can be called from a variety of languages including C, Visual Basic, and Java. The callable library consists of a set of functions that (1) input the problem size and data, (2) set options and tolerances, (3) perform steps 1 through 3 to create an initial reference set, (4) retrieve a trial solution from OPTQUEST to be input to the improvement method, and (5) input the solution resulting from the improvement method back into OPTQUEST, which uses it as the input to step 7 of the scatter search protocol. The improvement method is provided by the user. We use the term improvement loosely here because the user can simply provide an evaluation of the objective and constraint functions. [Pg.409]

In evaluating Eq. (C.23), we invoked orthonormality between the spatial orbitals a and b, each of which contains an electron of different spin. However, in a UHF wave function, the a and orbitals are not necessarily orthogonal to one another (only within each set, either (X or jS, are all of the orbitals mutually orthogonal to one another). In that case, the second and third terms on the r.h.s of Eq. (C.23) survive as — a b. In general, one can show that for a UHF wave function where the number of a electrons is greater than or equal to the number of electrons, the expectation value of may be computed as... [Pg.571]

Up to this point we have considered only those evaluations where the following procedure was invoked. (1) An initial mathematical functional form distribution f(M) was assumed. (2) Analogous experimental data u( ) were numerically computed. (3) A distribution f(M) was inferred using Equations 20 and 21. (4) Finally, the computed u( ) and the observed u( ) were compared. In what follows a true experimental justification of the validity of this technique is discussed. [Pg.232]

The quantum mechanical forms of the correlation function expressions for transport coefficients are well known and may be derived by invoking linear response theory [64] or the Mori-Zwanzig projection operator formalism [66,67], However, we would like to evaluate transport properties for quantum-classical systems. We thus take the quantum mechanical expression for a transport coefficient as a starting point and then consider a limit where the dynamics is approximated by quantum-classical dynamics [68-70], The advantage of this approach is that the full quantum equilibrium structure can be retained. [Pg.401]

In recent years numerous experiments have been reported on the fluorescence and energy transfer processes of electronically excited atoms. However, for flame studies the rates of many possible collision processes are not well known, and so the fate of these excited atoms is unclear. An interesting example concerns the ionization of alkali metals in flames. When the measured ionization rates are interpreted using simple kinetic theory, the derived ionization cross sections are orders of magnitude larger than gas kinetic (1,2,3). More detailed analyses (4,5) have yielded much lower ionization cross sections by invoking participation of highly excited electronic states. Evaluation of these models has been hampered by the lack of data on the ionization rate as a function of initial state for the alkali metals. [Pg.175]

The positions at which sequences differences occur when compared to other ancient and modem individuals can be evaluated with regard to what is known about the functional constraints acting on a sequence. For example, substitutions in protein-coding genes that result in stop codons or unlikely amino acid replacements may invoke suspicion until verified by additional extracts.28... [Pg.417]

To render Eq. (2) tractable for a structure analysis, several approximations are made. The Born-Oppenheimer approximation is invoked, so that the potential energy term in Eq. (3) is just the total electronic energy. It is usually further assumed that the potential for the nuclei is quadratic. In this case it is easy to solve for t(Q, Q 0) in Eq. (3), but Eq. (2) cannot be easily evaluated without further assumptions of the charge density as a function of Q. The practice is to partition p(r, Q) into a sum of charge density functions that are centered on the several nuclei and to further assume that each density function follows the motion of the nucleus on which it is centered. This latter factorization has dubious validity, but nonetheless forms the basis of a working approximation for both structural and charge density analysis of x-ray diffraction data. [Pg.541]

The first boundary condition is equivalent to a finite value of I a at the symmetry point in spherical coordinates. This condition was invoked in Section 17.2 along the symmetry axis of long cylindrical catalysts to eliminate the modified zeroth-order Bessel function of the second kind, = 0), from the general solution given by equation (17-22). When the symmetry condition at the center of a spherical pellet is used to evaluate the integration constants, one finds that B = 0 in equation (17-28) because ... [Pg.478]

The translational partition function can be evaluated by invoking a continuous spectrum of energy levels in the high-temperature hmit, where results from quantum mechanics are synonymous with those from classical mechanics. Under these conditions. [Pg.767]

Numerous studies pertaining to upd-adsorbates have been reported that contain data on the bond distance between substrate atoms and deposits and the relative positions of the involved atoms [572-579]. Beyond these data the valence state of the adsorbed atoms and modifications of the electronic structure of the support upon adsorption of the upd-layer could be determined. In an approach where only the absorption modulation intensity is evaluated, changed electronic properties of platinum particles deposited on a carbon support could be explained by invoking changing charge on the metal as a function of the electrode potential [580]. In a comparison of carbon-supported platinum modified with upd-Sn and a carbon-supported... [Pg.141]


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Evaluation function

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