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991.
Some properties of arcwise connected functions in terms of their directional derivatives are investigated. These properties are then utilized to establish necessary and sufficient optimality conditions for scalar-valued nonlinear programming problems. Mond–Weir type duality results are also proved. 相似文献
992.
Figurina T. Yu. Ovseevich A. I. 《Journal of Optimization Theory and Applications》1999,100(2):349-364
This paper deals with the attainable sets of linear periodic control systems. The asymptotic behavior of the attainable sets over a long time interval is investigated in terms of shapes of the sets. The shape of a set stands for the totality of all its images under nonsingular linear transformations. It is shown that there exist limits of the shape of attainable sets corresponding to time instants with the same residue modulo the period of the system and that the limit shapes are different if the system includes a stable subsystem. 相似文献
993.
H. Xu 《Mathematical Programming》1999,84(2):401-420
n to Rm. Under the assumption of semi-smoothness of the mapping, we prove that the approximation can be obtained through the Clarke
generalized Jacobian, Ioffe-Ralph generalized Jacobian, B-subdifferential and their approximations. As an application, we
propose a generalized Newton’s method based on the point-based set-valued approximation for solving nonsmooth equations. We
show that the proposed method converges locally superlinearly without the assumption of semi-smoothness. Finally we include
some well-known generalized Newton’s methods in our method and consolidate the convergence results of these methods.
Received October 2, 1995 / Revised version received May 5, 1998 Published online October 9, 1998 相似文献
994.
Given a nondecreasing sequence (
n
) of sub--fields and a real or vector valued random variable f, the Lévy Martingale convergence Theorem (LMCT) asserts that E(f/
n
) converges to E(f/) almost surely and in L
1, where stands for the -field generated by the
n
. In the present paper, we study the validity of the multivalued analog this theorem for a random set F whose values are members of (X), the space of nonempty closed sets of a Banach space X, when (X) is endowed either with the Painlevé–Kuratowski convergence or its infinite dimensional extensions. We deduce epi-convergence results for integrands via the epigraphical multifunctions. As it is known, these results are useful for approximating optimization problems. The method relies on countability supportness hypotheses which are shown to hold when the values of the random set E(F/
n
) do not contain any line. On the other hand, since the values of F are not assumed to be bounded, conditions involving barrier and asymptotic cones are shown to be necessary. Moreover, we discuss the relations with other multivalued martingale convergence theorems and provide examples showing the role of the hypotheses. Even in the finite dimensional setting, our results are new or subsume already existing ones. 相似文献
995.
We develop the notion of t-homogeneous, G-semiregular large sets of t-designs, show that there are infinitely many 3-homogeneous PSL(2, q)-semiregular large sets when q 3 mod 4, two sporadic 3-homogeneous AL(1,32)-semiregular large sets, and no other interesting t-homogeneous G-semiregular large sets for t 3. 相似文献
996.
关于隶属函数和属性测度的注记 总被引:1,自引:0,他引:1
胡志斌 《数学的实践与认识》1999,29(4):93-96
讨论了隶属函数和属性测度的数学涵义,并讨论了它们的一个基本关系式。 相似文献
997.
引进偏Bochner积分的概念.证明了在不可分清形下,偏Bochner积分与Bochner积分有本质的差异.作为应用,通过向量测度空间用价Bochner积分给出了Radon-Nikodym性质的一个刻划. 相似文献
998.
Alec Norton 《Proceedings of the American Mathematical Society》1999,127(10):3111-3118
If is the (unique) minimal set for a diffeomorphism of the circle without periodic orbits, , then the upper box dimension of is at least . The method of proof is to introduce the exponent into the proof of Denjoy's theorem.
999.
We investigate maximal functions involving averages over geodesics in three-dimensional Riemannian manifolds. We first show that one can easily extend the Euclidean results of Bourgain and Wolff if one assumes constant curvature. These results need not hold if this assumption is dropped. Nonetheless, we formulate a generic geometric condition which allows favorable estimates. Curiously, this condition ensures that one is in some sense as far as possible from the constant curvature case. Assuming this, one can prove dimensional estimates for Nikodym-type sets which are essentially optimal. Optimal estimates for the related maximal functions are still open though.
1000.
本文在不分明化拓扑中从θ-开集出发给出了θ-连续函数和θ-紧性的概念,并讨论了它们的某些性质. 相似文献