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作者：SILVERMAN, BG
摘要：There are many tools and much literature that combine the expert systems and mathematical modeling paradigms. This survey focuses on a subset consisting of: decision making and unification, and not mere co-existence, of the two approaches. The unification effort is new and presents many research challenges at the theoretical, methodological, and tool levels. At the theoretical level, accepted prescriptions now exist that stipulate in which situations it is valid to use various forms of mathema...
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作者：SMITH, JM
摘要：State-dependent queues and finite capacity queueing network models of facilities are important tools for the topological design of facilities, the routing of customers, and the allocation of resources to accommodate customer traffic. Key properties of these M/G/C/C queueing models and their applications in facility planning are described in detail. The incorporation of these concepts, tools, and techniques is important to the OR profession because they provide a unifying, system-wide planning ...
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作者：BAILEY, MP
摘要：This work gives a methodology for analyzing a class of discrete minimization problems with random element weights. The minimum weight solution is shown to be an absorbing state in a Markov chain, while the distribution of weight of the minimum weight element is shown to be of phase type. We then present two-sided bounds for matroids with NBUE distributed weights, as well as for weights with bounded positive hazard rates. We illustrate our method using a realistic military communications problem.
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作者：WHITE, CC; SCHERER, WT
作者单位：University of Michigan System; University of Michigan; University of Virginia
摘要：We develop bounds on the value function and a suboptimal design for the partially observed Markov decision process. These bounds and suboptimal design are based on the M most recent observations and actions. An a priori measure of the quality of these bounds is given. We show that larger M implies tighter bounds. An operations count analysis indicates that (#A#Z)M+1(#S) multiplications and additions are required per successive approximations iteration of the suboptimal design algorithm, where ...
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作者：FEDERGRUEN, A; TZUR, M
作者单位：University of Pennsylvania
摘要：We show for the general dynamic lot sizing model how minimal forecast horizons may be detected by a slight adaptation of an earlier O(n log n) or O(n) forward solution method for the model. A detailed numerical study indicates that minimal forecast horizons tend to be small, that is, include a small number of orders. We describe a new planning approach to ensure stability of the lot sizing decisions over an initial interval of time or stability horizon in those (relatively rare) cases where no...
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作者：BANERJEE, PK; KABADI, SN
作者单位：University of New Brunswick
摘要：A system with a functional life of T units of time requires a certain functional part for its operation. If this part fails before the failure of the system, it has to be replaced immediately to keep the system in operation. Two brands are available for replacements. These two brands differ in unit costs and life distributions. The objective is to determine a time-dependent replacement policy that minimizes the expected operational cost. We show that if certain conditions are satisfied, then t...
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作者：BITRAN, GR; GILBERT, SM
作者单位：University System of Ohio; Case Western Reserve University
摘要：A wide variety of manufacturing operations can be characterized as co-production with substitutable demand. That is, there are many situations in which the availability of two or more items are related, and because of randomness in either supply or demand, it can be advantageous to substitute one of these items for another. Our research was motivated by the semiconductor industry, where chips are produced in large batches. Because of the presence of randomness in the process, individual chips ...
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作者：DEMATTA, R; GUIGNARD, M
作者单位：University of Pennsylvania
摘要：Capacity-oriented production scheduling can be described as the assignment of competing products to several single level, capacitated production lines over a given planning horizon. This study was initially motivated by the production planning of various types of tiles by a tile manufacturing company. We considered different integer programming formulations and found that a disaggregated model, while increasing the size of the model, lends itself best to Lagrangian techniques and produces the ...
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作者：DANIELS, RL; MAZZOLA, JB
作者单位：Duke University
摘要：This paper explores the improvements in manufacturing efficiency that can be achieved by broadening the scope of production scheduling to include both the sequencing of work and the coordination of the resource inputs required to perform work. Recognizing that some resources are inherently flexible and thus can be reassigned dynamically to processing centers as needed, and that job processing times are often a function of the amount of resource dedicated to specific operations, we formulate th...
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作者：FRENK, H; LABBE, M; VANVLIET, M; ZHANG, SZ
作者单位：Universite Libre de Bruxelles
摘要：In this paper we present two algorithms for a machine allocation problem occurring in manufacturing systems. For the two algorithms presented we prove worst-case performance ratios of 2 and 3/2, respectively. The machine allocation problem we consider is a general convex resource allocation problem, which makes the algorithms applicable to a variety of resource allocation problems. Numerical results are presented for two real-life manufacturing systems.
