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41.
This paper presents a preference-based method to handle optimization problems with multiple objectives. With an increase in the number of objectives the computational cost in solving a multi-objective optimization problem rises exponentially, and it becomes increasingly difficult for evolutionary multi-objective techniques to produce the entire Pareto-optimal front. In this paper, an evolutionary multi-objective procedure is combined with preference information from the decision maker during the intermediate stages of the algorithm leading to the most preferred point. The proposed approach is different from the existing approaches, as it tries to find the most preferred point with a limited budget of decision maker calls. In this paper, we incorporate the idea into a progressively interactive technique based on polyhedral cones. The idea is also tested on another progressively interactive approach based on value functions. Results are provided on two to five-objective unconstrained as well as constrained test problems.  相似文献   
42.
Hydroxyl-group functional polylactones were prepared and converted to acid- terminated polyesters in a reaction with a series of alkenylsuccinic anhydrides containing 8, 12, or 18 carbons in their alkenyl chains. These polyester precursors were then linked into higher molecular weight poly(ester anhydrides) containing alkenyl moieties in their polyester blocks. The hydrolysis behaviour of the poly(ester anhydrides) was found to depend on the thermal properties of the polyester precursors. For poly(ester anhydrides) prepared from low molecular weight prepolymers with thermal transitions below 37 degrees C, the presence of hydrophobic alkenyl chains in the polyester precursors slowed the rate of weight loss. Poly(ester anhydrides) prepared from higher molecular weight prepolymers showed the opposite weight-loss behaviour; i.e., the crystallinity and thermal transitions of the alkenyl chain-containing poly(ester anhydrides) were low, and the weight loss was faster than for poly(ester anhydrides) without the alkenyl chains. The differences in length of the alkenyl chain, as such, had little effect on the hydrolysis behaviour and thermal properties of the poly(ester anhydrides).  相似文献   
43.
This technical note extends the results of our recent paper [Korhonen, Soleimani-damaneh, Wallenius, EJOR 215 (2011) 431–438], for determining the RTS status of Decision Making Units in Weight-Restricted DEA models.  相似文献   
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Generalized Logarithmic Derivative Estimates of Gol'dberg-Grinshtein Type   总被引:1,自引:0,他引:1  
For f meromorphic in the complex plane and meromorphic in theunit disc, sharp upper bounds are obtained for and where k andj are integers satisfying k > j 0. The results generalizethe logarithmic derivative estimate due to Gol'dberg and Grinshteinto derivatives of higher order. 2000 Mathematics Subject Classification30D35.  相似文献   
47.
The Flexible Ligand Unified Force Field (FLUFF) is a molecular mechanistic superposition algorithm utilizing a template structure, on top of which the ligand(s) are superimposed. FLUFF enables a flexible semiautomatic superimposition in which the ligand and the template are allowed to seek the best common conformation, which can then be used to predict the biological activity by Boundless Adaptive Localized Ligand (BALL). In BALL, the similarity of the electrostatic and van der Waals volumes of the template and ligand is evaluated using the template-based coordinate system which makes the FLUFF-BALL invariant as to the rotations and translations of the global coordinate system. When tested using the CBG (corticosteroid binding globulin) affinities of 31 benchmark steroids, the FLUFF-BALL technique produced results comparable to standard 3D-QSAR methods. Supplementary test calculations were performed with five additional data sets. Due to its high level of automation and high throughput, the FLUFF-BALL is highly suitable for use in drug design and in scanning of large molecular libraries.  相似文献   
48.

The zero sets of the Bergman space \(A^p_\omega \) induced by either a radial weight \(\omega \) admitting a certain doubling property or a non-radial Bekollé-Bonami type weight are characterized in the spirit of Luecking’s results from 1996. Accurate results obtained en route to this characterization are used to generalize Horowitz’s factorization result from 1977 for functions in \(A^p_\omega \). The utility of the obtained factorization is illustrated by applications to integration and composition operators as well as to small Hankel operator induced by a conjugate analytic symbol. Dominating sets and sampling measures for the weighted Bergman space \(A^p_\omega \) induced by a doubling weight are also studied. Several open problems related to the scheme of the paper are posed.

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49.
Cu chabazite catalysts show remarkable low temperature activity in selective catalytic reduction (SCR) of NO. This high activity is due to the unique character of the zeolite framework that allows only the presence of one type of isolated mononuclear Cu(2+) species. These Cu(2+) species are the active sites for SCR.  相似文献   
50.
A function , analytic in the unit disc , belongs to the weighted Hardy space if , where is the maximum modulus of in the circle of radius centered at the origin. If belongs to for some , then it is said to be an -function. Heittokangas has shown that all solutions of the linear differential equation

()

where is analytic in for all , are of finite order of growth in if and only if all coefficients are -functions.

It is said that when . In this study it is shown that if all coefficients of satisfy for all , then all nontrivial solutions of satisfy

where and

In addition, if is the smallest index for which

then there are at least linearly independent solutions of such that

These results are a generalization of a recent result due to Chyzhykov, Gundersen and Heittokangas.

  相似文献   

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