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981.
We present a lower and an upper bound for the second smallest eigenvalue of Laplacian matrices in terms of the averaged minimal cut of weighted graphs. This is used to obtain an upper bound for the real parts of the non-maximal eigenvalues of irreducible nonnegative matrices. The result can be applied to Markov chains. 相似文献
982.
A. A. Berezin 《Il Nuovo Cimento D》1987,9(6):731-733
Summary We suggest that the random distribution of stable isotopes may act as a contributing factor towards unpredictability and irreproducibility
in living systems. In this respect isotopic randomness could act as a counterpart or competitor of the ?standard? quantum-mech
cal indeterminism. 相似文献
983.
关于Riemann流形中的2-调和子流形 总被引:2,自引:0,他引:2
讨论了黎曼流形中的 2-调和子流形,获得了这类子流形的第二基本形式模长平方和Ricci曲率的pinching定理:设M是n+p维黎曼流形N的具有平行平均曲率向量的n维 2-调和子流形,如果N的截面曲率的上、下确界分别记为KN和KN,则当M的第二基本形式模长平方s[ (n-1)KN-KN+nH2 ]时,M是极小子流形。 相似文献
984.
Alain Miranville 《Applications of Mathematics》2003,48(1):31-47
In this article we introduce the notion of a minimal attractor for families of operators that do not necessarily form semigroups. We then obtain some results on the existence of the minimal attractor. We also consider the nonautonomous case. As an application, we obtain the existence of the minimal attractor for models of Cahn-Hilliard equations in deformable elastic continua. 相似文献
985.
In this article, we consider max-min controllability in linear pursuit games with norm-bounded controls. Our approach is based on the separation theorem of disjoint compact convex sets in Euclidean space. Necessary and sufficient conditions for max-min controllability are given in terms of an explicit relative controllability expression which, in a sense, is a comparison between the control capabilities of the competing parties. Minimal time and optimal norm problems are investigated. 相似文献
986.
S. Norgėla 《Lithuanian Mathematical Journal》2005,45(1):94-101
We describe the tableau and inverse calculi for the propositional modal logic S4. The formulas are treated as sets of paths. We obtain the upper bound for the number of applications of rules in the deduction tree.__________Translated from Lietuvos Matematikos Rinkinys, Vol. 45, No. 1, pp. 117–126, January–March, 2005.Translated by R. Lapinskas 相似文献
987.
988.
M.S. Osman Mahmoud A. Abo-Sinna A.A. Mousa 《Applied mathematics and computation》2005,170(2):7427-840
This paper presents a combined genetic algorithm-fuzzy logic controller (GA–FLC) technique for constrained nonlinear programming problems. In the standard Genetic algorithms, the upper and lower limits of the search regions should be given by the decision maker in advance to the optimization process. In general a needlessly large search region is used in fear of missing the global optimum outside the search region. Therefore, if the search region is able to adapt toward a promising area during the optimization process, the performance of GA will be enhanced greatly. Thus in this work we tried to investigate the influence of the bounding intervals on the final result. The proposed algorithm is made of classical GA coupled with FLC. This controller monitors the variation of the decision variables during process of the algorithm and modifies the boundary intervals to restart the next round of the algorithm. These characteristics make this approach well suited for finding optimal solutions to the highly NLP problems. Compared to previous works on NLP, our method proved to be more efficient in computation time and accuracy of the final solution. 相似文献
989.
Wojciech Buszkowski 《Mathematical Logic Quarterly》2003,49(5):467-474
Compact Bilinear Logic (CBL), introduced by Lambek [14], arises from the multiplicative fragment of Noncommutative Linear Logic of Abrusci [1] (also called Bilinear Logic in [13]) by identifying times with par and 0 with 1. In this paper, we present two sequent systems for CBL and prove the cut‐elimination theorem for them. We also discuss a connection between cut‐elimination for CBL and the Switching Lemma from [14]. 相似文献
990.
L. L. Maksimova 《Algebra and Logic》2005,44(6):407-421
We study into the interpolation property and the projective Beth property in extensions of Johansson's minimal logic. A family
of logics of some special form is considered. Effective criteria are specified which allow us to verify whether an arbitrary
logic in this family has a given property.
Supported by RFBR grant No. 03-06-80178, by the Council for Grants (under RF President) and State Aid of Fundamental Science
Schools, project NSh-2069.2003.1, and by INTAS grant No. 04-77-7080.
__________
Translated from Algebra i Logika, Vol. 44, No. 6, pp. 726–750, November–December, 2005. 相似文献