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Search objective function constant

The activation energy of the propagation reaction (Ep) and that of association equilibriim reaction (Eeq) are reported to be 6.13 Kcal/gmole and 38.6 Kcal/gmole respectively ( ). A non-linear search of the data (Equation 14) will define the constants a b c, and d. Data at 16.6 C and 21 C were incorporated with a least square objective function using Luus and Jaakola s (18) method. The analysis resulted in the following relationships ... [Pg.386]

The objective function, F, as a function of iteration, during the search is shown in Figure 6. The objective function decreases rapidly and has neared the minimum value after approximately 20 Iterations. The trial values for the rate constants are shown in Figure 7. The values for k level off after about 30 Iterations, while k., which has less effect on the value of the objective function, does not level off until about 60 iterations. The convergence criteria is not met until almost 120 iterations. Since the rate constants are essentially determined after 60 iterations, the computer time could be decreased without affecting the accuracy of the final answer by using a less stringent criteria. [Pg.246]

With integration of (50) or (51) the considered time interval rb is taken equal to either the duration of the components stay in whole reactor or in a zone where the limiting stage of the process occurs. The values Xj, here, are very often set constant. Depending on the statement of the problem solved, sometimes they can be taken equal to the values of corresponding components of vector y, and sometimes they can be calculated on the basis of search for the extremum of the objective function on the auxiliary MEISs. It is clear that by replacing all variables in the integrals of the form... [Pg.32]

Assume that an optimum feed flow rate trajectory is searched for the emulsion copolymerization problem described in Section 8.3.3. In this case, also assume that the copolymer composition should be constant throughout the batch. Also assume that the final monomer conversion should be as close as possible to 1, to allow for rninirnization of the residual monomer. In order to achieve the control objectives, one is allowed to manipulate the feed flow rate of monomer 1, which is assumed to be the most reactive monomer, and the initial monomer concentrations. In this particular case, one may write the following objective function ... [Pg.346]

Univariate search in the case of two parameters, P- and 2- The contours ofthe objective function and the successive parameter estimates are shown. As every time one parameter is kept constant, one always searches parallel to one ofthe parameter axes. [Pg.287]

There is an appreciable groundwork for development of methods for construction and analysis of trajectories on the MEIS base. It resulted from extensive studies on the search for results of processes possible in the region of thermodynamic attainability D ( /). A key component of these studies is an extension of the experience gained in the convex analysis of ideal systems (Van der Waals and Konstamm, 1936 Zeldovich, 1938 Gorban, 1984) to modeling of real ones (Antsiferov, 1991 Kaganovich et al., 1989, 1993, 1995, 2007, 2010). They may include an ideal (or real) gas phase, plasma, condensed substances, solutions and other components. The components of this analysis are determination of particularities of the objective function and study on the properties of set Dj(y). For MEIS with variable parameters solution of the first mentioned problem proves to be non-tiivial, when the sum in expression (8) with the constant value of y is replaced by the... [Pg.50]

Various optimum search methods exist for the minimization of objective functions, which can be used for the estimation of kinetic constants [3], for example, the Fibonacci method, the golden section method, the Newton-Raphson method, the Levenberg-Marquardt method, and the simplex method. Recently, even genetic algorithms have been... [Pg.598]

Structural models of protein and nucleic acid molecules derived by X-ray crystallography are exttemely interesting in themselves, each being a representative member of some architectural class of macromolecule shaped by evolutionary time and process toward the optimal completion of a specific cellular or metabolic task. They are nevertheless static objects. Because the catalytic functions they perform depend on dynamic events involving the interaction of the macromolecules with substrates, effectors, inhibitors, and other cellular components, we are constantly searching for techniques that will allow us to visualize the macromolecules in some intermediate stages of a biochemical or physiological activity. [Pg.232]

To address this problem, we outline a method where the space cost minimization problem can be handled implicitly by extending the search space. We exploit the observation that the space cost fimction for each vessel is essentially a step function that depends on the number of berths in the terminal. Note that the number of berths in a terminal is relatively small (compared to the number of vessels). Furthermore, the space objective cost-function is constant within a berth. [Pg.83]


See other pages where Search objective function constant is mentioned: [Pg.543]    [Pg.408]    [Pg.72]    [Pg.115]    [Pg.528]    [Pg.221]    [Pg.354]   
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