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排序方式: 共有1861条查询结果,搜索用时 19 毫秒
1.
Mikhail Andramonov 《Journal of Global Optimization》2002,24(2):115-132
We consider applications of disjunctive programming to global optimization and problems with equilibrium constraints. We propose a modification of the algorithm of F. Beaumont for disjunctive programming problems and show its numerical efficiency. 相似文献
2.
就一般非完整约束系统,从约束方程满足的变分恒等式出发,利用增广位形流形上的向量场定义三类非自由变分,即非完整变分:vakonomic变分、Hlder变分、Suslov变分,并讨论它们之间的关系以及它们成为自由变分的充要条件.利用非完整变分以及相应的积分变分原理建立两类动力学方程:vakonomic方程和Routh方程或Chaplygin方程.通过vakonomic方程分别与Routh方程和Chaplygin方程比较,得到它们具有共同解的两类充分必要条件.这些条件并不是约束的可积性条件.
关键词:
非完整约束
非完整变分
Chetaev条件
vakonomic动力学 相似文献
3.
An applied cell mapping method for optimal control problems 总被引:1,自引:0,他引:1
W. H. Zhu 《Journal of Optimization Theory and Applications》1989,60(3):485-500
From the application point of view, a series of modifications are proposed for the cell mapping method discussed in Ref. 1 for the optimal control analysis of dynamical systems. The cell order around the target set is rearranged. A set of common discriminate principles is used for the selection of the optimal one among competing control strategies of the same cost. Inequality constraints of the system are taken into account. The number of elements in the set of allowable time intervals is not prescribed, but left open. These modifications seem to make the cell mapping method more efficient for analyzing feedback systems and for obtaining their global optimal control information. The algorithms presented in this paper could broaden the application of the cell mapping approach of Ref. 1 to a wider class of engineering problems. 相似文献
4.
Lihong Wang 《Annals of the Institute of Statistical Mathematics》2004,56(2):251-264
The purpose of this paper is to investigate the asymptotic properties of the least squares estimates (L
2-estimates) and the least absolute deviation estimates (L
1-estimates) of the parameters of a nonlinear regression model subject to a set of equality and inequality restrictions, which
has a long-range dependent stationary process as its stochastic errors. Then we will compare the asymptotic relative efficiencies
of the above estimators. 相似文献
5.
6.
Annegret K. Wagler 《4OR: A Quarterly Journal of Operations Research》2005,3(4):329-336
Shepherd95 proved that the stable set polytopes of near-bipartite graphs are given by constraints associated with the complete
join of antiwebs only. For antiwebs, the facet set reduces to rank constraints associated with single antiwebs by Wagler2004.
We extend this result to a larger graph class, the complements of fuzzy circular interval graphs, recently introduced in ChudnovskySeymour2004.
Received: November 2004 / Revised version: June 2005 相似文献
7.
In this paper, we investigate a constrained optimization problem with a quadratic cost functional and two quadratic equality constraints. It is assumed that the cost functional is positive definite and that the constraints are both feasible and regular (but otherwise they are unrestricted quadratic functions). Thus, the existence of a global constrained minimum is assured. We develop a necessary and sufficient condition that completely characterizes the global minimum cost. Such a condition is of essential importance in iterative numerical methods for solving the constrained minimization problem, because it readily distinguishes between local minima and global minima and thus provides a stopping criterion for the computation. The result is similar to one obtained previously by the authors. In the previous result, we gave a characterization of the global minimum of a constrained quadratic minimization problem in which the cost functional was an arbitrary quadratic functional (as opposed to positive-definite here) and the constraints were at least positive-semidefinite quadratic functions (as opposed to essentially unrestricted here). 相似文献
8.
Y. Yavin 《Journal of Optimization Theory and Applications》1993,78(1):77-91
Stochastic optimal control techniques are applied to compare the performance of identical medium-range air-to-air missiles which have different thrust-mass profiles. The measure of the performance is the probability of reaching a lock-on-point with a favorable range of guidance and flight parameters, during a fixed time interval [0,t
f
], given that, during the flight, the trajectories of the missile are subjected to a variety of constraints including dynamic pressure constraints. 相似文献
9.
We present a new generic problem solving approach for over-constrained problems based on Max-SAT. We first define a Boolean
clausal form formalism, called soft CNF formulas, that deals with blocks of clauses instead of individual clauses, and that allows one to declare each block either as hard (i.e., must be satisfied by any solution) or soft (i.e., can be violated by some solution). We then present two Max-SAT solvers that find a truth assignment that satisfies
all the hard blocks of clauses and the maximum number of soft blocks of clauses. Our solvers are branch and bound algorithms
equipped with original lazy data structures, powerful inference techniques, good quality lower bounds, and original variable
selection heuristics. Finally, we report an experimental investigation on a representative sample of instances (random 2-SAT,
Max-CSP, graph coloring, pigeon hole and quasigroup completion) which provides experimental evidence that our approach is
very competitive compared with the state-of-the-art approaches developed in the CSP and SAT communities.
Research partially supported by projects TIN2004-07933-C03-03 and TIC2003-00950 funded by the Ministerio de Educación y Ciencia. The second author is supported by a grant Ramón y Cajal. 相似文献
10.
G.J. Zalmai Qing-hong Zhang 《应用数学学报(英文版)》2007,23(2):217-234
In this paper,we discuss a large number of sets of global parametric sufficient optimality condi-tions under various gcneralized (η,ρ)-invexity assumptions for a semi-infinite minmax fractional programmingproblem. 相似文献