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Optimization procedures evaluation

In the near future the technique will be further evaluated using ultrasonic signals from natural defects, e.g., fatigue cracks. The performance measure and the parameter optimization procedure wilt also be refined in order to obtain a computationally efficient implementation, easy to use for a trained operator. [Pg.95]

This mathematical optimization procedure is a rational process because the slope (or derivative) enables us to know which way to go and how far to go. In contrast, in the search procedure, we just arbitrarily choose some values of x at which to evaluate the function. Those arbitrary choices are much like what people do in most design situations. They are simply searching in a rather crude mannerfotThe solution to the problem, and they will not achieve the solution precisely. With mathematical optimization, our hope is both to speed up that process and to get a more precisely optimum solution. [Pg.430]

The following protocols are not optimized procedures for EIA, but they are suitable for screening, e.g., for antibody titers of sera or mAb cell culture supernatants. A high-performance EIA has to be evaluated with respect to selection of type of microtiter plates, coating concentration, coating conditions, analyte dilution, sample buffer, washing buffer, incubation times and temperatures, conjugate dilution, and substrate composition. [Pg.157]

The model [C] can be evaluated by comparing with [D] using a -criterion. The parameters of the model can be optimized by some optimization procedure (Simplex). [Pg.82]

The MCSCF optimization process is only the last step in the computational procedure that leads to the MCSCF wave function. Normally the calculation starts with the selection of an atomic orbital (AO) basis set, in which the molecular orbitals are expanded. The first computational step is then to calculate and save the one- and two-electron integrals. These integrals are commonly processed in different ways. Most MCSCF programs use a supermatrix (as defined in the closed shell HF operator) in order to simplify the evaluation of the energy and different matrix elements. The second step is then the construction of this super-matrix from the list of two-electron integrals. The MCSCF optimization procedure includes a step, where these AO integrals are transformed to MO basis. This transformation is most effectively performed with a symmetry blocked and ordered list of AO integrals. Step... [Pg.197]

By varying the geometries in the program, an optimum design can be achieved. The choice of column diameter was a critical decision in the optimization procedure. In order to evaluate the effect of changing the column diameter, various column diameters were used and the number of trays required was determined. The results of these test runs are shown in Table G.l... [Pg.290]

Following, we determine the effects of the interactions between the quantum and classical subsystems on the optimization procedures of the MCSCF electronic wavefunction by evaluating the contributions of the quantum-classical interactions to the gradient and Hessian terms in the above equation. [Pg.542]

Cocaine has been extracted from coca leaves and the optimization procedure was investigated by means of a central composite design [17]. Pressure, temperature, nature, and percentage of polar modifier were studied. A rate of 2 mL/min CO2 modified by the addition of 29 % water in methanol at 20 M Pa for 10 min allowed the quantitative extraction of cocaine. The robustness of the method was evaluated by drawing response surfaces. The same compound has also been extracted by SEE from hair samples [18-20]. [Pg.344]

Quantitative analyses are usually carried out by comparing the measured quantities of test samples with those of standards with known concentrations. Due to the uniqueness of the vibrational spectrum of a compound, individual bands can often be found which make it possible to carry out multicomponent analyses, even with mixtures of ten or more constituents. Another advantage is the extremely wide variety of samples which can be analyzed by vibrational spectroscopy. The prerequisites and the evaluation procedures for single as well as for multicomponent analyses have been described extensively by Weitkamp and Barth (1976). Several optimization procedures have been published by Junker and Bergmann (1974, 1976). [Pg.412]

An important number of references have been published dealing with many applications of supported liquid membranes. Mathematical modeling of the process has been developed and it can be generalized and applied to the determination of the response of different systems containing more than one solute. After evaluation of the parameters, process optimization can be applied using common optimization procedures, as described in the text. [Pg.1036]

The SRM transitions for the analyte and its IS are preferentially selected as a common neutral loss. In many automatic optimization procedures for SRM, the selection of the SRM transition is based on the maximum response. However, from selectivity point of view, additional criteria based on structure specificity, selectivity, and enhanced S/N in the analysis of real samples are important. The selection of an SRM transition by evaluating the background noise and the absence of interferences was reported by Woolf et al. [33] for the bioanalysis of an indinavir metabolite. [Pg.296]

The general behaviour of simulated annealing in correcting for shift errors has been evaluated by comparing the p ormances of different optimization procedures simplex, steepest descent, and emulated aimealing in the resolution of two- and three-components overlapped synthetic band syst ns. [Pg.94]

The alternative is to employ a multivariate optimization procedure such as Simplex. Simplex is an algorithm that seeks the vector of parameters that corresponds to the separation optimum within an n-dimensional experimental space. For example, a two-parameter CE separation optimized by Simplex would begin with three observations of the separation response at three different electrolyte conditions. These conditions are chosen by the analyst, often his or her best guess. From the evaluation of the response of each observation, the algorithm chooses the next experimental condition for investigation (4). As with the univariate method, the experiments continue until an optimal separation condition is determined. The disadvantage of such an approach is that it is unknown how many experiments are required to achieve an optimum, or if the optimum is local or global as the entire response surface is not known. [Pg.170]

Based on the best conqiosition of promoters, the conqiosation of main components was optimized. The contents of V, Sb, W, Sn and supporter were taken as five influences, and Xp, Sacn also as the outcomes. 20 Original sample points were distributed, at wdiich the catalysts were prepared and evaluated. The ranges of the results were, Xp 11.6% 88.2%, Sacn 15.0% 44.4% and Yacn 2.4% 28.9%. Accordingly, A 5-20-12-2 network was adopted in the sequential iterative procedure. The results of the optimization and evaluation in the first and second iteration are listed in Table 1 and 2. [Pg.1113]


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