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作者:DOBSON, G
摘要:In this paper, we formulate the cyclic lot scheduling problem on a single facility with sequence-dependent setup costs and times and provide a heuristic solution procedure. A Lagrangian relaxation of the formulation leads to a partial separation of the embedded lot sizing and traveling salesman problems. The relaxation results in a new combinatorial problem related to the minimum spanning tree problem. The information about frequency of production, gained from the solution to this relaxation, ...
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作者:AHMADI, JH; AHMADI, RH; DASU, S; TANG, CS
作者单位:University of California System; University of California Los Angeles
摘要:We consider a situation in which the manufacturing system is equipped with batch and discrete processors. Each batch processor can process a batch (limited number) of jobs simultaneously. Once the process begins, no job can be released from the batch processor until the entire batch is processed. In this paper, we analyze a class of two-machine batching and scheduling problems in which the batch processor plays an important role. Specifically, we consider two performance measures: the makespan...
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作者:LEE, CY; UZSOY, R; MARTINVEGA, LA
作者单位:Purdue University System; Purdue University; National Science Foundation (NSF)
摘要:In this paper, we study the problem of scheduling semiconductor bum-in operations, where burn-in ovens are modeled as batch processing machines. A batch processing machine is one that can process up to B jobs simultaneously. The processing time of a batch is equal to the largest processing time among all jobs in the batch. We present efficient dynamic programming-based algorithms for minimizing a number of different performance measures on a single batch processing machine. We also present heu...
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作者:AKELLA, R; RAJAGOPALAN, S; SINGH, MR
作者单位:University of Michigan System; University of Michigan; University of Southern California
摘要:This paper concerns dynamic part dispatch decisions in electronic test systems with random yield. A discrete time, multiproduct, miltistage production system is used as a model for the test system with the objective to minimize the sum of inventory holding, backlogging, and overtime costs over a finite horizon. Exact results for such systems have been limited to either single-stage, multiple time period, or multistage, single time period problems with a single product. Here we develop two appr...
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作者:LI, CL; SIMCHILEVI, D; DESROCHERS, M
作者单位:Universite de Montreal; Universite de Montreal; Polytechnique Montreal; Columbia University
摘要:We analyze the vehicle routing problem with constraints on the total distance traveled by each vehicle. Two objective functions are considered: minimize the total distance traveled by vehicles and minimize the number of vehicles used. We demonstrate a close relationship between the optimal solutions for the two objective functions and perform a worst case analysis for a class of heuristics. We present a heuristic that provides a good worst case result when the number of vehicles used is relati...
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作者:ROSENFIELD, DB
作者单位:Massachusetts Institute of Technology (MIT)
摘要:In a recent article, the author presented results for the optimum levels of inventory to dispose and keep in an excess inventory situation. This note shows that these levels do not change when additional disposal opportunities are presented in the future. In this sense, the optimal policy is myopic in that the decision can be made without any examination of future decisions.
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作者:GERCHAK, Y; MOSSMAN, D
摘要:We explore analytically cardinal effects of the extent of demand randomness on optimal inventory levels and the associated expected costs. To model changes in demand randomness, we make extensive use of a mean-preserving transformation commonly used in probabilistic microeconomics, as well as the notion of risk-pooling (aggregating independent demands). For the single period (news vendor) model, the order quantity and associated costs are shown to depend on the randomness parameter in a simple...
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作者:FEDERGRUEN, A; ZHENG, YS
作者单位:University of Pennsylvania
摘要:The reorder point/reorder quantity policies, also referred to as (r, Q) policies, are widely used in industry and extensively studied in the literature. However, for a period of almost 30 years there has been no efficient algorithm for computing optimal control parameters for such policies. In this paper, we present a surprisingly simple and efficient algorithm for the determination of an optimal (r*, Q*) policy. The computational complexity of the algorithm is linear in Q*. For the most preva...
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作者:LEE, J
摘要:This note treats optimization problems that involve two criteria on set systems. One is a bottleneck criterion, and the other is general. In particular, recent algorithms for such problems on the edge-sets of networks are related to the fundamental work of J. Edmonds and D. R. Fulkerson involving more general set systems.
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作者:GEOFFRION, AM
摘要:The purposes of this paper-a revised and extended version of the Omega Rho Lecture given at the November 1991 ORSA/TIMS Joint National Meeting-are to assess some important aspects of the current MS/OR situation and to draw some conclusions about desirable future emphases. To these ends, it identifies and discusses four forces of historic importance (the microcomputer and communications revolutions, the dispersion of MS/OR in industry, and academia's unbalanced reward structure), three major tr...