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991.
Jayanta Kumar Dey Shyamal Kumar Mondal Manoranjan Maiti 《European Journal of Operational Research》2008
A finite time horizon inventory problem for a deteriorating item having two separate warehouses, one is a own warehouse (OW) of finite dimension and other a rented warehouse (RW), is developed with interval-valued lead-time under inflation and time value of money. Due to different preserving facilities and storage environment, inventory holding cost is considered to be different in different warehouses. The demand rate of item is increasing with time at a decreasing rate. Shortages are allowed in each cycle and backlogged them partially. Shortages may or may not be allowed in the last cycle and under this circumstance, there may be three different types of model. Here it is assumed that the replenishment cycle lengths are of equal length and the stocks of RW are transported to OW in continuous release pattern. For each model, different scenarios are depicted depending upon the re-order point for the next lot. Representing the lead-time by an interval number and using the interval arithmetic, the single objective function for profit is changed to corresponding multi-objective functions. These functions are maximized and solved by Fast and Elitist Multi-objective Genetic Algorithm (FEMGA). The models are illustrated numerically and the results are presented in tabular form. 相似文献
992.
Leszek Skrzypczak 《Journal of Fourier Analysis and Applications》2008,14(3):415-442
We consider weighted function spaces of Sobolev-Besov type and Schrödinger type operators on noncompact Riemannian manifolds with bounded geometry. First we give characterization of the spaces in terms of wavelet frames. Then we describe the necessary and sufficient conditions for the compactness of Sobolev embeddings between the spaces. An asymptotic behavior of the corresponding entropy numbers is calculated. At the end we use the asymptotic behavior to estimate the number of negative eigenvalues of the Schrödinger type operators. 相似文献
993.
In this paper, we present a uniform strong law of large numbers for random set-valued mappings in separable Banach space and apply it to analyze the sample average approximation of Clarke stationary points of a nonsmooth one stage stochastic minimization problem in separable Banach space. Moreover, under Hausdorff continuity, we show that with probability approaching one exponentially fast with the increase of sample size, the sample average of a convex compact set-valued mapping converges to its expected value uniformly. The result is used to establish exponential convergence of stationary sequence under some metric regularity conditions. 相似文献
994.
Werner Linde 《Journal of Fourier Analysis and Applications》2008,14(4):568-587
Let u be a (bounded, linear) operator from a Hilbert space ℋ into the Banach space C(T), the space of continuous functions on the compact metric space T. We introduce and investigate numbers τ
n
(u), n≥1, measuring the degree of determinism of the operator u. The slower τ
n
(u) decreases, the less determined are functions in the range of u by their values on a certain set of points. It is shown that n
−1/2
τ
n
(u)≤2e
n
(u), where e
n
(u) are the (dyadic) entropy numbers of u. Furthermore, we transform the notion of strong local nondeterminism from the language of stochastic processes into that
of linear operators. This property, together with a lower entropy estimate for the compact space T, leads to a lower estimate for τ
n
(u), hence also for e
n
(u). These results are used to prove sharp lower entropy estimates for some integral operators, among them, Riemann–Liouville
operators with values in C(T) for some fractal set T. Some multi-dimensional extensions are treated as well.
相似文献
995.
郭嗣琮 《数学的实践与认识》2008,38(2):87-93
简述了模糊值函数分析学在具体工程实践应用中存在的困难和障碍,系统地介绍了模糊结构元方法在模糊值函数分析学中的应用,包括模糊结构元的概念、模糊数的模糊结构元表示形式、基于结构元表达形式的模糊数运算与隶属函数确定.模糊结构元方法将复杂的模糊数运算转化为一类单调有界函数的运算,不仅仅为模糊分析计算的简化提供了工具,同时也为模糊值函数分析学应用的研究开创了一条新的途径. 相似文献
996.
关于自然数幂和的两个改进不等式 总被引:1,自引:0,他引:1
钟五一 《数学的实践与认识》2008,38(5):128-133
应用分析的方法得到了关于自然数幂和的两个改进不等式,并证明了有关的四个常数均为最佳值. 相似文献
997.
An arrangement of the multi-set {1,1,2,2,…,n,n} is said to be “split-pair” if for all i<n, between the two occurrences of i there is exactly one i+1. We enumerate the number of split-pair arrangements and in particular show that the number of such arrangements is (−1)n+1n2(22n−1)B2n where Bi is the ith Bernoulli number. 相似文献
998.
999.
We consider three random variables X_n, Y_n and Z_n, which represent the numbers of the nodes with 0, 1, and 2 children, in the binary search trees of size n. The expectation and variance of the three above random variables are got, and it is also shown that X_n, Y_n and Z_n are all asymptotically normal as n→∞by applying the contraction method. 相似文献
1000.
Fix nonnegative integers n1,…,nd and let L denote the lattice of integer points (a1,…,ad)∈Zd satisfying 0?ai?ni for 1?i?d. Let L be partially ordered by the usual dominance ordering. In this paper we offer combinatorial derivations of a number of results concerning chains in L. In particular, the results obtained are established without recourse to generating functions or recurrence relations. We begin with an elementary derivation of the number of chains in L of a given size, from which one can deduce the classical expression for the total number of chains in L. Then we derive a second, alternative, expression for the total number of chains in L when d=2. Setting n1=n2 in this expression yields a new proof of a result of Stanley [Enumerative Combinatorics, vol. 2, Cambridge University Press, Cambridge, 1999] relating the total number of chains to the central Delannoy numbers. We also conjecture a generalization of Stanley's result to higher dimensions. 相似文献