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71.
Boris S. Mordukhovich 《Journal of Global Optimization》2008,40(1-3):225-244
This article is devoted to the study of some extremality and optimality notions that are different from conventional concepts
of optimal solutions to optimization-related problems. These notions reflect certain amounts of linear subextremality for
set systems and linear suboptimality for feasible solutions to multiobjective and scalar optimization problems. In contrast
to standard notions of optimality, it is possible to derive necessary and sufficient conditions for linear subextremality
and suboptimality in general nonconvex settings, which is done in this article via robust generalized differential constructions
of variational analysis in finite-dimensional and infinite-dimensional spaces.
相似文献
72.
T. Ramallingam 《Annals of the Institute of Statistical Mathematics》1989,41(4):677-681
The exact probability density function of linear combinations of k=k(n) order statistics selected from the whole order statistics (L-statistic) based on a random sample of size n from the uniform distribution on [0, 1] was derived by Matsunawa (1985, Ann. Inst. Statist. Math., 37, 1–16). As the main expression for the density function given by Matsunawa is not complete for the general situation, we first provide the corrections for this formula. Second, we propose a simple scheme involving symbolic computing for evaluating the corrected version of the density function. The cumulative distribution function and the r-th mean of his L-statistic are also derived. 相似文献
73.
Aboubakari Traore Benjamin Mampassi Bisso Saley 《Central European Journal of Mathematics》2007,5(4):751-763
In this paper we consider the problem of detecting pollution in some non linear parabolic systems using the sentinel method.
For this purpose we develop and analyze a new approach to the discretization which pays careful attention to the stability
of the solution. To illustrate convergence properties we give some numerical results that present good properties and show
new ways for building discrete sentinels.
相似文献
74.
Izidor Gertner 《Stochastic Processes and their Applications》1978,7(3):231-246
The structure of a nonlinear filter with observation process having continuous and discontinuous components is considered. The approach is based on the so-called “Bayes” formula for conditional expectations. “Fubini” type theorems for stochastic integrals are given and used to obtain the representations of an optimal estimate and of the conditional likelihood ratio. A linear unnormalized filtering equation for controlled system process is derived. 相似文献
75.
大花无柱兰是一种珍稀兰科植物,具有一定的观赏和药用价值,但数量十分稀少,该物种亟待保护。本研究采用SRAP分子标记技术,对10个居群的115份DNA样品进行PCR扩增,并开展遗传多样性分析。从81对引物中筛选出9个条带清晰、多态性好、重复性高的引物组合,共扩增得到305条谱带。在物种水平上,多态性比率(PPB)为100%,Nei’s基因多样性指数(H )为0.209 8,Shannon’s指数(I )为0.340 2;在居群水平上,PPB为24.59%~52.13%,H 为0.079 6~0.165 5,I 为0.120 9~0.252 3。居群水平上,基因分化度(Gst)为0.520 9,基因流(Nm)为0.459 9,遗传距离为0.091 9~0.198 4。UPGMA聚类结果表明,10个居群可分为3大类,地理距离相近的居群优先聚集。大花无柱兰的遗传多样性较为丰富,居群间存在一定的遗传分化和基因交流,可采用就地保护和人工栽培等方式加以保护。 相似文献
76.
77.
78.
We characterize boundedness and compactness of products of differentiation operators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bloch spaces with general weights. 相似文献
79.
An improved hybrid adjoint method to the viscous, compressible Reynold-Averaged Navier-Stokes Equation (RANS) is developed for the computation of objective function gradient and demonstrated for external aerodynamic design optimization. In this paper, the main idea is to extend the previous coupling of the discrete and continuous adjoint method by the grid-node coordinates variation technique for the computation of the variation in the gradients of flow variables. This approach in combination with the Jacobian matrices of flow fluxes refrained the objective function from field integrals and coordinate transformation matrix. Thus, it opens up the possibility of employing the hybrid adjoint method to evaluate the subsequent objective function gradient analogous to many shape parameters, comprises of only boundary integrals. This avoids the grid regeneration in the geometry for every surface perturbation in a structured and unstructured grid. Hence, this viable technique reduces the overall CPU cost. Moreover, the new hybrid adjoint method has been successfully applied to the computation of accurate sensitivity derivatives. Finally, for the investigation of the presented numerical method, simulations are carried out on NACA0012 airfoil in a transonic regime and its accuracy and effectiveness related to the new gradient equation have been verified with the Finite Difference Method (FDM). The analysis reveals that the presented methodology for the optimization provides the designer with an indispensable CPU-cost effective tool to reshape the complex geometry airfoil surfaces, useful relative to the state-of-the-art, in a less computing time. 相似文献
80.