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151.
1IntroductionConsiderthelinearregressioumodelcensoredfromtheleft:K=m{K,0}=rnax{Z:W ei,0},1Si5n,(1.1)whereZi=(1,X:),,15i5n,7o=(ac,P6)'(1'2)ThedimensionalityofXiisd21.WeobBerve(Xi,K)',1SiSn.Basedontheseobservations,wetrytogivesomeestimationofac,ortesthypothesisonit.Themodelwasfirstconsideredbycabin[llundertheassumptionthatelfe2,''arelid.withacommonnormaldistributionN(0,rs:).HedefinedtheMLEof7o,whichnowisusuallyknownastheTobinestimator.TheconsistencyOfthisestimatorwasestablishedbyAmend… 相似文献
152.
153.
F. Blanchini 《Journal of Optimization Theory and Applications》1991,71(3):465-484
The linear state feedback synthesis problem for uncertain linear systems with state and control constraints is considered. We assume that the uncertainties are present in both the state and input matrices and they are bounded. The main goal is to find a linear control law assuring that both state and input constraints are fulfilled at each time. The problem is solved by confining the state within a compact and convex positively invariant set contained in the allowable state region.It is shown that, if the controls, the state, and the uncertainties are subject to linear inequality constraints and if a candidate compact and convex polyhedral set is assigned, a feedback matrix assuring that this region is positively invariant for the closed-loop system is found as a solution of a set of linear inequalities for both continuous and discrete time design problems.These results are extended to the case in which additive disturbances are present. The relationship between positive invariance and system stability is investigated and conditions for the existence of positively invariant regions of the polyhedral type are given.The author is grateful to Drs. Vito Cerone and Roberto Tempo for their comments. 相似文献
154.
Multi-objective optimization using evolutionary algorithms identifies Pareto-optimal alternatives or their close approximation by means of a sequence of successive local improvement moves. While several successful applications to combinatorial optimization problems are known, studies of underlying problem structures are still scarce. 相似文献
155.
C. D. Bisbos 《Optimization Letters》2007,1(1):101-109
Limit and shakedown analysis problems of Computational Mechanics lead to convex optimization problems, characterized by linear objective functions, linear equality constraints and constraints expressing the restrictions imposed by the material strength. It is shown that two important strength criteria, the Mohr–Coulomb and the Tresca criterion, can be represented as systems of semidefinite constraints, leading this way to semidefinite programming problems. 相似文献
156.
In this paper, we propose and analyze an SQP-type method for solving linearly constrained convex minimization problems where the objective functions are too complex to be evaluated exactly. Some basic results for global convergence and local superlinear convergence are obtained according to the properties of the approximation sequence. We illustrate the applicability of our approach by proposing a new method for solving two-stage stochastic programs with fixed recourse. 相似文献
157.
Satoru Ibaraki Masao Fukushima Toshihide Ibaraki 《Computational Optimization and Applications》1992,1(2):207-226
A primal-dual version of the proximal point algorithm is developed for linearly constrained convex programming problems. The algorithm is an iterative method to find a saddle point of the Lagrangian of the problem. At each iteration of the algorithm, we compute an approximate saddle point of the Lagrangian function augmented by quadratic proximal terms of both primal and dual variables. Specifically, we first minimize the function with respect to the primal variables and then approximately maximize the resulting function of the dual variables. The merit of this approach exists in the fact that the latter function is differentiable and the maximization of this function is subject to no constraints. We discuss convergence properties of the algorithm and report some numerical results for network flow problems with separable quadratic costs. 相似文献
158.
一类特殊二维0-1规划的广义指派模型求解 总被引:2,自引:2,他引:0
二维0-1整数规划模型应用广泛,对广义指派问题的研究,解决了一些二维0-1整数规划问题.但有些实际问题具有特殊上限约束,目前还没有对应的方法.针对该实际情形,本文建立了相应的数学模型,利用对指派模型的推广,求得问题最优解,从理论上解决了这一类特殊约束二维0-1整数规划的最优解求取问题.并通过算例说明了方法的使用. 相似文献
159.
K. C. Kiwiel 《Journal of Optimization Theory and Applications》2007,134(3):549-554
We give a linear time algorithm for the continuous quadratic knapsack problem which is simpler than existing methods and competitive
in practice. Encouraging computational results are presented for large-scale problems.
The author thanks the Associate Editor and an anonymous referee for their helpful comments. 相似文献
160.
基于模糊方法的多人合作对策的研究 总被引:2,自引:0,他引:2
多人合作对策模型中联盟的收入和总体的收入常常出现相互矛盾的情况 ,此时核是空集 .由于不存在核 ,无法用 Nash-Harsanyi谈判模型求解 .采用模糊数学方法 ,调整模型中线性约束的右端系数 ,使核在一定程度上是非空集合 ,得到模糊意义下的 Nash平衡解 .该方法一定程度上解决了各联盟收入与总体收入的矛盾 .最后通过一个算例说明该方法的可行性 . 相似文献