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Preference functions evaluation

If we wish to avoid the additional objective function evaluation at p=qa/2, we can use the extra information that is available at p=0. This approach is preferable for differential equation models where evaluation of the objective function requires the integration of the state equations. It is presented later in Section 8.7 where we discuss the implementation of Gauss-Newton method for ODE models. [Pg.141]

PROMETHEE evaluates discrete alternatives based on pairwise comparisons for each sub-objective. However, these comparisons are not performed "manually". Instead, partial preference functions, usually using the difference between two alternatives attribute values as data input, are used to perform the pairwise comparisons. These partial preference functions have to be defined for each sub-objective as a first step of using PROMETHEE. They are used to determine the decision maker s strength of preference for an alternative (with 0 assigned for indifference, 1 for strict preference and values between 0 and 1 for intermittent preference values). [Pg.144]

The remaining factors of Eq. (7.16) will make up the integrand involved in a canonical partition function. But we will prefer to evaluate a grand canonical partition function. In doing this, we will select the appropriate m factors of the activity out of the activities available, and denote that combination by z . The ) feature will be zero for cases that N isn t sufficient to supply the ligand set m. Therefore, all nonzero contributions will be proportional to the factor of z . [Pg.148]

A guideline for choosing a suitable method is to avoid approximations as much as possible. Thus, plots of concentration, or a function of concentrations, versus time or reactor space time are preferred for evaluation of experiments with batch, tubular, and differential recycle reactors, in which concentrations are directly measured and rates can only be obtained by a finite-difference approximation (see eqns 3.1, 3.2, 3.5, 3.6, and 3.8). On the other hand, plots of the rate, or a function of the rate, versus concentration or a function of concentrations serve equally well for evaluation of results from CSTRs or differential reactors without recycle (gradientless reactors), where concentrations and rate are related to one another by algebraic equations that involve no approximations (see eqns 3.3, 3.4, or 3.7). [Pg.45]

It is often preferable to evaluate 6q by EMD methods because the director fluctuates around the preferred orientation in a shear flow simulation, which makes it hard to obtain accurate estimates. If one performs such a simulation one must fix the director at several alignment angles and calculate the antisymmetric pressure tensor, which, according to Eq. (4.10e), is a linear function of cos 26. One can fit a straight line to the data points and the zero gives... [Pg.348]

Two data bases of soluble proteins of known structure used to find false positive prediction results (Table I and Table II). Gaussian parameters needed for evaluation of preference functions based on the Kyte-Doolittle hydropathy scale [17] (Table III). Table with detailed prediction results for transmembrane helices in 168 integral membrane proteins (Table IV). Table with a detailed comparison of prediction results for 10 best known membrane proteins for our and three other algorithms (Table V). All these tables together with the FORTRAN 77 source code are available from the anonymous ftp server mia.os.camet.hr in the /pub/pssp directory. The anonymous login is ftp and the e-mail address is accepted as password. The list of files with short descriptions is contained in the 00index.txt file. [Pg.441]

As roughly sketched in the introduction, metabolic hydroxylation mediated by cytochrome P450 is attributed to a ferro-oxyl species, called Compoimd I (Cpd I). From present knowledge, Cpd I may be seen as an electrophilic oxidant [6], Thus fhe/ function (calculated for the substrates) should help identify those positions in a molecule, which are susceptible to an attack by Cpd I. Conversely, the function, evaluated for Cpd I, should show where Cpd I prefers to be attacked by the substrate. Atomic HOMO coefficients from semiempirical calculations on agrochemicals have already been quite successfully correlated to oxidative metabolic pathways [33-34], This procedure is essentially equivalent to calculating the/ function in the frozen orbital approximation, in whichreduces to the HOMO density. In the examples section, a nice demonstration of the breakdown of this approximation will be given. [Pg.230]

Sequential methods are preferable when the maximum number of function evaluations needs to be considered parallel methods are more high performance in terms of time required to reach the solution, and if it is possible to compute the function on several processors. [Pg.45]

By proper choice of the contraction parameters one can thus use basis functions that are approximate atomic Hartree-Fock functions. Slater-type functions, etc., while still evaluating integrals only with primitive Gaussian functions. A procedure that has come into wide use is to fit a Slater-type orbital (STO) to a linear combination of L = 1,2, 3,... primitive Gaussian functions. This is the STO-LG procedure (the procedure is commonly referred to as STO-NG, but since N represents the number of electrons everywhere in this book, we prefer an alternative symbol). In particular, STO-3G basis sets are often used in polyatomic calculations, in preference to evaluating integrals with Slater functions. We will use STO-3G basis sets for our model calculations on H2 and HeH. We need to explicitly consider the form that the contraction (3.212) takes if is to approximate a s Slater-type function. [Pg.156]

The use of higher-order schemes is often the preferred solution, in spite of requiring several function evaluations per time step for each of... [Pg.532]

E-3, evaluate each of your models to determine the probability of this system functioning on demand. Calculate the Bimbaum, Inspection and Risk Achievement Worth Ratio for each of the components using which ever model you prefer. (Once you get the cutsets, it does not matter which model was used as long as it is a correct system model.)... [Pg.497]

Pseudo-Newton-Raphson methods have traditionally been the preferred algorithms with ab initio wave function. The interpolation methods tend to have a somewhat poor convergence characteristic, requiring many function and gradient evaluations, and have consequently primarily been used in connection with semi-empirical and force field methods. [Pg.335]

Strict requirement and can be theoretically met only if we know the underlying continuous function that provides the values of the derivatives at the time points of a discrete representation. The availability, though, of such a continuous function is based on a series of ad hoc decisions on the character and properties of the functions, and if one prefers to avoid them, then one must accept a series of approximations for the evaluation of first and second derivatives. These approximations provide a sequence of representations with increasing abstraction, leading, ultimately, to qualitative descriptions of the state and trend as follows (Cheung and Stephanopoulos, 1990) ... [Pg.219]


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See also in sourсe #XX -- [ Pg.412 , Pg.414 ]




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