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1.
Ranking fuzzy numbers with integral value   总被引:110,自引:0,他引:110  
Ranking fuzzy numbers is important in decision making. Since very often the alternatives are evaluated by fuzzy numbers in a vague environment, a comparison between these fuzzy numbers is indeed a comparison between alternatives. This paper proposes a method of ranking fuzzy numbers with integral value. The method, which is independent of the type of membership functions used and the normality of the functions, can rank more than two fuzzy numbers simultaneously. It is relatively simple in computation, especially in ranking triangular and trapezoidal fuzzy numbers. Further, an index of optimism is used to reflect the decision maker's optimistic attitude. Discussion on comparative advantages is included.  相似文献
2.
一类双对称矩阵反问题的最小二乘解   总被引:55,自引:0,他引:55       下载免费PDF全文
1.问题的提出近年来,对于矩阵反问题AX=B的研究已取得了一系列的结果[1],获得了解存在的条件,但由于实际问题中X,B由实验给出,很难保证满足解存在的条件,因此研究问题的最小二乘解是有实际意义的.本文就结构设计中用到的一类双对称矩阵的最小二乘问题进行探讨.令R~(n×m)表示所有n×m阶实矩阵集合,R~n=R~(n×1) 表示其中秩为r的子集;OR~(n×n) 表示所有n阶正交阵之集;A~( )表示矩阵A的Moore-Penrose广义逆;I_k表示k阶单位阵;||·||表示Frobenius范数;表示SR~(n…  相似文献
3.
双对称矩阵逆特征值问题解存在的条件   总被引:48,自引:6,他引:42  
1.引言逆特征值问题在工程中应用广泛,例如逆特征值方法是飞行器设计中的振动设计和振动林制的有力下具.关干研特征相问领的研守己有一ngfRtr的结里【1].f21.[31分另11就对称拉肚类和一般矩阵类进行了研究,双对称阵在土木工程和振动工程中有实际应用,但其逆特征值问题尚未研究,本文将讨论这个问题.用R"""表示所有nx。阶实矩阵集合,R7""表示其中秩为r的子集;11·1是矩阵的Frobenius范数;A十表示矩阵A的Moors-Penrose广义逆;OR"""表不所有n阶正交阵全体;人表示k阶单位阵;**"""表示n阶实对称阵的全体;战一(ek,ek-1…  相似文献
4.
On the limited memory BFGS method for large scale optimization   总被引:48,自引:0,他引:48  
We study the numerical performance of a limited memory quasi-Newton method for large scale optimization, which we call the L-BFGS method. We compare its performance with that of the method developed by Buckley and LeNir (1985), which combines cycles of BFGS steps and conjugate direction steps. Our numerical tests indicate that the L-BFGS method is faster than the method of Buckley and LeNir, and is better able to use additional storage to accelerate convergence. We show that the L-BFGS method can be greatly accelerated by means of a simple scaling. We then compare the L-BFGS method with the partitioned quasi-Newton method of Griewank and Toint (1982a). The results show that, for some problems, the partitioned quasi-Newton method is clearly superior to the L-BFGS method. However we find that for other problems the L-BFGS method is very competitive due to its low iteration cost. We also study the convergence properties of the L-BFGS method, and prove global convergence on uniformly convex problems.This work was supported by the Applied Mathematical Sciences subprogram of the Office of Energy Research, U.S. Department of Energy, under contract DE-FG02-87ER25047, and by National Science Foundation Grant No. DCR-86-02071.  相似文献
5.
2紧优双环网络无限族   总被引:46,自引:0,他引:46  
找到两个2紧优双环网络的无限族,这肯定地回答了李乔等人于1993年提出的一个问题。  相似文献
6.
In this paper, we establish a theorem of the alternative in ordered linear topological spaces. Then, optimality conditions for the optimization of set-valued maps are obtained.  相似文献
7.
Shortest paths algorithms: Theory and experimental evaluation   总被引:37,自引:0,他引:37  
We conduct an extensive computational study of shortest paths algorithms, including some very recent algorithms. We also suggest new algorithms motivated by the experimental results and prove interesting theoretical results suggested by the experimental data. Our computational study is based on several natural problem classes which identify strengths and weaknesses of various algorithms. These problem classes and algorithm implementations form an environment for testing the performance of shortest paths algorithms. The interaction between the experimental evaluation of algorithm behavior and the theoretical analysis of algorithm performance plays an important role in our research. This work was done while Boris V. Cherkassky was visiting Stanford University Computer Science Department and supported by the NSF and Powell Foundation grants mentioned below. Andrew V. Goldberg was supported in part by ONR Young Investigator Award N00014-91-J-1855, NSF Presidential Young Investigator Grant CCR-8858097 with matching funds from AT&T, DEC, and 3M, and a grant from Powell Foundation. Corresponding author. This work was done while Tomasz Radzik was a Postdoctoral Fellow at SORIE, Cornell University, and supported by the National Science Foundation, the Air Force Office of Scientific Research, and the Office of Naval Research, through NSF grant DMS-8920550, and by the Packard Fellowship of éva Tardos.  相似文献
8.
具有空间扩散的种群系统解的存在唯一性与边界控制   总被引:34,自引:1,他引:33  
本文讨论了带年龄结构和空间扩散的时变种群系统的最优边界控制问题,证明了系统的广义解的存在唯一性,得到了控制为最优的充分必要条件以及由积分-偏微分方程和变分不等式构成的最优性组.最优控制u∈uad是由最优性组所确定的.  相似文献
9.
Benson Proper Efficiency in the Vector Optimization of Set-Valued Maps   总被引:34,自引:0,他引:34  
This paper extends the concept of cone subconvexlikeness of single-valued maps to set-valued maps and presents several equivalent characterizations and an alternative theorem for cone-subconvexlike set-valued maps. The concept and results are then applied to study the Benson proper efficiency for a vector optimization problem with set-valued maps in topological vector spaces. Two scalarization theorems and two Lagrange multiplier theorems are established. After introducing the new concept of proper saddle point for an appropriate set-valued Lagrange map, we use it to characterize the Benson proper efficiency. Lagrange duality theorems are also obtained  相似文献
10.
Swarm intelligence is a research branch that models the population of interacting agents or swarms that are able to self-organize. An ant colony, a flock of birds or an immune system is a typical example of a swarm system. Bees’ swarming around their hive is another example of swarm intelligence. Artificial Bee Colony (ABC) Algorithm is an optimization algorithm based on the intelligent behaviour of honey bee swarm. In this work, ABC algorithm is used for optimizing multivariable functions and the results produced by ABC, Genetic Algorithm (GA), Particle Swarm Algorithm (PSO) and Particle Swarm Inspired Evolutionary Algorithm (PS-EA) have been compared. The results showed that ABC outperforms the other algorithms.  相似文献
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