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151.
Andrew Ya. Olenko Tibor K. Pogány 《Journal of Mathematical Analysis and Applications》2006,324(1):262-280
Time shifted aliasing error upper bound extremals for the sampling reconstruction procedure are fully characterized. Sharp upper bounds are found on the aliasing error of truncated cardinal series and the corresponding extremals are described for entire functions from certain specific Lp, p>1, classes. Analogous results are obtained in multidimensional regular sampling. Truncation error analysis is provided in all cases considered. Moreover, sharpness of bounding inequalities, convergence rates and various sufficient conditions are discussed. 相似文献
152.
设ψ(n)是Euler函数,r是正实数.以E(x,r)表示和式的渐近公式中的误差项,本文研究了E(x,r)的算术均值和积分均值. 相似文献
153.
山背波对飞机的潜在威胁现已毋庸置疑。为了提高在这方面作出更确切判断的能力并能进一步找出实践中可行的相应措施,首要的问题就是必须对山背波本身有足够的认识,而这正是当前国内文献中极为薄弱的环节。有鉴于此,本文系统地、较全面地介绍了山背波这种独特的次声波,对其发生机理和基本特征、以及作为其直接衍生物的相关云相和晴空湍流--后者正是对飞机的主要潜在威胁所在--作出简明扼要的评述。 相似文献
154.
Military course of action planning involves time and space synchronization as well as resource and asset allocation. A mission could be seen as a defined set of logical ordered tasks with time and space constraints. The resources to task rules require that available assets should be allocated to each task. A combination of assets might be required to execute a given task. The couple (task, resources) constitutes an action. This problem is formulated as a multi-objectives scheduling and resource allocation problem. Any solution is assessed based on a number of conflicting and heterogeneous objectives. In fact, military planning officers should keep perfecting the plan based on the Commander’s criteria for success. The scheduling problem and resource allocation problem are considered as NP-Hard Problems [A. Guitouni, B. Urli, J.-M. Martel, Course of action planning: A project based modelling, Working Paper, Faculté des sciences de l’ administration, Université Laval, Québec, 2005]. This paper is concerned with the multi-objectives resource allocation problem. Our objective is to find adequate resource allocation for given courses of action schedule. To optimize this problem, this paper investigates non-exact solution methods, like meta-heuristic methods for finding potential efficient solutions. A progressive resource allocation methodology is proposed based on Tabu Search and multi-objectives concepts. This technique explores the search space so as to find a set of potential efficient solutions without aggregating the objectives into a single objective function. It is guided by the principle of maximizing the usage of any resource before considering a replacement resource. Thus, a given resource is allocated to the maximum number of tasks for a given courses of action schedule. A good allocation is a potential efficient solution. These solutions are retained by applying a combination of a dominance rule and a multi-criteria filtering method. The performance of the proposed Pareto-based approach is compared to two aggregation approaches: weighted-sum and the lexicographic techniques. The result shows that a Pareto-based approach is providing better solutions and allowing more flexibility to the decision-maker. 相似文献
155.
In this paper we propose a new model for the p-median problem. In the standard p-median problem it is assumed that each demand point is served by the closest facility. In many situations (for example, when demand points are communities of customers and each customer makes his own selection of the facility) demand is divided among the facilities. Each customer selects a facility which is not necessarily the closest one. In the gravity p-median problem it is assumed that customers divide their patronage among the facilities with the probability that a customer patronizes a facility being proportional to the attractiveness of that facility and to a decreasing utility function of the distance to the facility. 相似文献
156.
(M, g)是黎曼曲面,该文给出了M上函数的Φ- Dirichlet积分的定义,并在此基础上得到了一个关于具有有限的Φ - Dirichlet积分的Φ -次调和函数的有界性定理. 相似文献
157.
Inneke Van Nieuwenhuyse Nico Vandaele Kumar Rajaram Uday S. Karmarkar 《European Journal of Operational Research》2007
This paper studies the impact of management policies, such as product allocation and campaign sizing, on the required size of the finished goods inventories in a multi-product multi-reactor batch process. Demand, setup and batch processing times for these products are assumed to be stochastic, and the inventory buffer for every product type needs to be such that target customer service levels are met. To perform this analysis, we develop a queueing model that allows us to explicitly estimate service levels as a function of the buffer size, and the allocation/campaign sizing policies. This model can be used to evaluate the service level given an existing buffer configuration, as well as to determine the buffer sizes required across products to meet a pre-specified service level. It also allows us to formulate a number of insights into how product allocation decisions and campaign planning policies affect buffer sizing decisions in symmetric production systems. 相似文献
158.
零级狄里克莱级数的增长性 总被引:8,自引:0,他引:8
高宗升 《武汉大学学报(理学版)》1994,(2)
首先研究了全平面上零级狄里克莱级数的系数和增长性之间的关系,然后证明了对于本级随机狄里克莱级数所确定的随机整函数,在每条水平直线上的增长性几乎必然(a.s.)与相应的狄里克莱级数所确定的整函数的增长性相同. 相似文献
159.
For a semilinear heat equation we consider a nonlocal boundary problem. On the basis of the solution of a Dirichlet problem for a parabolic equation and Volterra integral equation we establish the well-posedness for the nonlocal problem, which generalizes some recent results. 相似文献
160.
We study the maximal term of the Hadamard composition of Dirichlet series with real exponents. We obtain a lower estimate for the sum of a Dirichlet series over a curve arbitrarily approaching the convergence line. 相似文献