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作者：TAKAGI, H
摘要：Queues with a finite population of customers and occasional periods (called vacations) when the server is unavailable appear in many engineering systems, but have not been studied. In this paper, we specifically consider an M/G/1//N queueing system in which the server takes repeated vacations each time it has emptied the queue, until it finds a customer waiting. For the steady state, we show that performance measures such as the system throughput and mean response time can be obtained from the...
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作者：HERZBERG, M; YECHIALI, U
作者单位：Tel Aviv University
摘要：Accelerating procedures for solving discounted Markov decision processes problems are developed based on a one-step lookahead analysis of the value iteration algorithm. We apply the criteria of minimum difference and minimum variance to obtain good adaptive relaxation factors that speed up the convergence of the algorithm. Several problems (including Howard's automobile replacement) are tested and a preliminary numerical evaluation reveals considerable reductions in computation time when compa...
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作者：COURCOUBETIS, C; WEBER, R
作者单位：University of Cambridge; AT&T; Nokia Corporation; Nokia Bell Labs
摘要：We consider a flexible manufacturing facility that can be operated in any of m different modes. While running in mode k certain intermediate products are consumed and other intermediate or finished products are created. There may be variability in the manufacturing process, as well as random arrivals of raw materials and orders for finished products. We establish conditions that ensure demands can be satisfied while maintaining bounded levels of inventories. These results that may be viewed as...
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作者：LI, SL; TIRUPATI, D
作者单位：University of Texas System; University of Texas Austin
摘要：This paper examines a multiproduct dynamic investment model for making technology choices and expansion decisions over a finite planning horizon. The motivation for our problem comes from recent developments in the field of flexible technology such as CAD, CAM, and CIM that permit firms to invest in these more expensive, flexible technologies to provide a competitive edge in the form of an ability to respond rapidly to changing product mix. On the other hand, more specialized (dedicated) equip...
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作者：DROR, M
摘要：In this note we prove that the relaxation approach in designing the subproblem of pricing out only the feasible routes for the set partition formulation of the VRPTW is justified on complexity grounds. That is, the first dynamic programming model presented in M. Desrochers, J. Desrosiers and M. Solomon (1992), that is able to price out all feasible routes, is NP-hard in the strong sense.
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作者：REISMAN, A; KIRSCHNICK, F
作者单位：Siemens AG; Siemens Germany
摘要：Ackoff has decried the ''devolution'' of OR/MS, Corbett and Van Wassenhove have spoken of its ''natural drift,'' and a sociologist has described its ''regression'' as typifying that of other learned professions. To shed light on these views, we undertook a detailed survey of a segment of the OR/MS literature, with particular focus on the space in flagship journals devoted to theory on the one hand and applications on the other. While the literature of OR/MS contains many articles and texts wit...
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作者：ROSENBERG, E; GLEIT, A
摘要：Many static and dynamic models have been used to assist decision making in the area of consumer and commercial credit. The decisions of interest include whether to extend credit, how much credit to extend, when collections on delinquent accounts should be initiated, and what action should be taken. We survey the use of discriminant analysis, decision trees, and expert systems for static decisions, and dynamic programming, linear programming, and Markov chains for dynamic decision models. Since...
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作者：RUSSELL, RA; LEUNG, JMY
作者单位：University of Arizona
摘要：In this paper, we discuss the problem of devising a cost effective schedule for a baseball league. Sports scheduling is a notoriously difficult problem. A schedule must satisfy constraints on timing such as the number of games to be played between every pair of teams, the bounds on the number of consecutive home (or away) games for each team, that every pair of teams must have played each other in the first half of the season, and so on. Often, there are additional factors to be considered for...
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作者：FISHER, ML
摘要：We consider the problem of optimally scheduling a fleet of K vehicles to make deliveries to n customers subject to vehicle capacity constraints. Given a graph with n + 1 nodes, a K-tree is defined to be a set of n + K edges that span the graph. We show that the vehicle routing problem can be modeled as the problem of finding a minimum cost K-tree with two K edges incident on the depot and subject to some side constraints that impose vehicle capacity and the requirement that each customer be vi...
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作者：LECUYER, P; PERRON, G
摘要：We show that under the (sufficient) conditions usually given for infinitesimal perturbation analysis (IPA) to apply for derivative estimation, a finite-difference scheme with common random numbers (FDC) has the same order of convergence, namely 0(n-1/2) , provided that the size of the finite-difference interval converges to zero fast enough. This holds for both one- and two-sided FDC. This also holds for different variants of IPA, such as some versions of smoothed perturbation analysis (SPA), ...
