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作者：SPERANZA, MG; UKOVICH, W
作者单位：University of Trieste
摘要：This paper deals with the problem of determining the frequencies at which several products have to be shipped on a common link to minimize the sum of transportation and inventory costs. A set of feasible shipping frequencies is given. Transportation costs are supposed to be proportional to the number of journeys performed by vehicles of a given capacity. Vehicles may or may not be supposed to carry out completely all materials available, and products assigned to different frequencies may or ma...
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作者：WEBER, RR; WEISS, G
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：Customers move through a series of M service stations. Each customer, independent of all others, requires service from only one of the stations, for a duration of 1 time unit, this being station i with probability p(i). The customer has zero service at all the other stations, but there is no overtaking between the customers, and so queueing occurs. In the case where there is unlimited waiting room between the servers, we show that the system is interchangeable-permuting the order of the statio...
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作者：GLASSERMAN, P; TAYUR, S
作者单位：Carnegie Mellon University
摘要：Most models of multilevel production and distribution systems assume unlimited production capacity at each site. When capacity limits are introduced, an ineffective policy may lead to increasingly large order backlogs: The stability of the system becomes an issue. In this paper, we examine the stability of a multi-echelon system in which each node has limited production capacity and operates under a base-stock policy. We show that if the mean demand per period is smaller than the capacity at e...
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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...
