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991.
A note on Constrained Total Least-Squares estimation 总被引:5,自引:0,他引:5
Burkhard Schaffrin 《Linear algebra and its applications》2006,417(1):245-258
It is shown here how - similarly to the unconstrained case - the Constrained Total Least Squares Estimate (CTLSE) can be generated by solving a certain sequence of eigenvalue problems iteratively. For this, the normal matrix from the constrained (standard) least-squares approach has to be suitably augmented by one row and one column. Further modification of the augmented row and column allows the treatment of “fiducial constraints” for which the RHS vector is affected by random errors, but not the constraining matrix itself. 相似文献
992.
An overview of bilevel optimization 总被引:4,自引:0,他引:4
This paper is devoted to bilevel optimization, a branch of mathematical programming of both practical and theoretical interest.
Starting with a simple example, we proceed towards a general formulation. We then present fields of application, focus on
solution approaches, and make the connection with MPECs (Mathematical Programs with Equilibrium Constraints).
B. Colson now at SAMTECH s.a., Liège, Belgium.
This article is an updated version of a paper that appeared in 4OR 3, 87–107, 2005. 相似文献
993.
Since 1996, eight elections have taken place in postcommunist Europe and Eurasia that have replaced illiberal with liberal governments. There is ample evidence that these “electoral revolutions” reflected the cross-national diffusion of a distinctive model of regime change that was developed elsewhere and that was designed to promote democratization in authoritarian political contexts featuring semi-competitive elections. This electoral model spread throughout the postcommunist region because of both shared perceptions by opposition groups of similar local conditions and the existence of transnational democracy promotion networks that included local, regional and American participants. As these revolutions spread, however, they were less successful in carrying through democratic change-in part because local conditions were less supportive and in part because authoritarian leaders and their international allies were both forewarned and forearmed. 相似文献
994.
中国城镇居民消费结构的平行数据分析 总被引:2,自引:0,他引:2
基于持久收入假设消费函数理论,运用平行数据模型建立中国城镇居民消费函数的计量形式,运用平行数据的基本模型、变截距模型和变系数模型进行估计和检验,分析中国城镇居民收入差异及其变动对消费结构变化的影响。 相似文献
995.
Z. Dostál 《Computational Optimization and Applications》2007,38(1):47-59
The implementation of the recently proposed semi-monotonic augmented Lagrangian algorithm for the solution of large convex
equality constrained quadratic programming problems is considered. It is proved that if the auxiliary problems are approximately
solved by the conjugate gradient method, then the algorithm finds an approximate solution of the class of problems with uniformly
bounded spectrum of the Hessian matrix at O(1) matrix–vector multiplications. If applied to the class of problems with the Hessian matrices that are in addition either
sufficiently sparse or can be expressed as a product of such sparse matrices, then the cost of the solution is proportional
to the dimension of the problems. Theoretical results are illustrated by numerical experiments.
This research is supported by grants of the Ministry of Education No. S3086102, ET400300415 and MSM 6198910027. 相似文献
996.
E.N. Mahmudov 《Journal of Mathematical Analysis and Applications》2005,307(2):628-640
Sufficient conditions of optimality are derived for convex and non-convex problems with state constraints on the basis of the apparatus of locally conjugate mappings. The duality theorem is formulated and the conditions under which the direct and dual problems are connected by the duality relation are searched for. 相似文献
997.
Gui‐Hua Lin 《Mathematical Methods in the Applied Sciences》2007,30(17):2179-2195
In this paper, we suggest a new relaxation method for solving mathematical programs with complementarity constraints. This method can be regarded as a modification of a method proposed in a recent paper (J. Opt. Theory Appl. 2003; 118 :81–116). We show that the main results remain true for the modified method and particularly, some conditions assumed in the previous paper can be removed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
998.
研究城镇居民消费结构的特点和变化,对引导城镇居民消费结构升级,完善国家有关政策具有积极的作用.本文运用多维灰色评估方法,结合1994年—2003年的统计资料,以山西省周边省份和部分发达省份为参照,对山西城镇居民消费结构进行动态比较分析,并提出相应的政策建议. 相似文献
999.
1000.
Heuristic approaches for solving transit vehicle scheduling problem with route and fueling time constraints 总被引:1,自引:0,他引:1
Electric bus scheduling problem can be defined as vehicle scheduling problem with route and fueling time constraints (VSPRFTC). Every vehicle’s travel miles (route time) after charging is limited, thus the vehicle must be recharged after taking several trips and the minimal charging time (fueling time) must be satisfied. A multiple ant colony algorithm (ACA) was presented to solve VSPRFTC based on ACA used to solve traveling salesman problem (TSP), a new metaheuristic approach inspired by the foraging behavior of real colonies of ants. The VSPRFTC considered in this paper minimizes a multiple, hierarchical objective function: the first objective is to minimize the number of tours (or vehicles) and the second is to minimize the total deadhead time. New improvement of ACA as well as detailed operating steps was provided on the basis of former algorithm. Then in order to settle contradiction between accelerating convergence and avoiding prematurity or stagnation, improvement on route construction rule and Pheromone updating rule was adopted. A group feasible trip sets (blocks) had been produced after the process of applying ACA. In dealing with the fueling time constraint a bipartite graphic model and its optimization algorithm are developed for trip set connecting in a hub and spoke network system to minimize the number of vehicle required. The maximum matching of the bipartite graph is obtained by calculating the maximum inflow with the Ford–Fulkerson algorithm. At last, an example was analyzed to demonstrate the correctness of the application of this algorithm. It proved to be more efficient and robust in solving this problem. 相似文献