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作者：LEFEBVRE, O; MICHELOT, C; PLASTRIA, F
作者单位：Vrije Universiteit Brussel
摘要：It is a well observed fact that in minisum multifacility location problems the optimal locations of several facilities often tend to coincide. Some sufficient conditions for this phenomenon, involving only the weights and applicable to any metric, have been published previously. The objective of this paper is to show how these conditions may be extended further and to obtain a more complete description of their implications, in particular, in the case of certain locational constraints.
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作者：ANILY, S; FEDERGRUEN, A
作者单位：Columbia University
摘要：We analyze a continuous-time, two-stage production/inventory system. In the first stage, a common intermediate product is produced in batches, and possibly stored. In the second phase, the intermediate product is fabricated into n distinct finished products. Several finished products may be included in a single production batch of limited capacity to exploit economies of scale. We propose a planning methodology to address the combined problem of joint setup costs and capacity limits (per setup...
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作者：ALTINKEMER, K; GAVISH, B
作者单位：Vanderbilt University
摘要：The delivery problem consists of finding a set of routes for a fleet of capacitated vehicles to satisfy the cargo delivery requirements of customers. The vehicles are located in a central depot, and have to fulfill the delivery requirements in a sequence that minimizes total delivery costs. Each vehicle tour starts and terminates at the central depot, and each node is supplied by exactly one vehicle. All vehicles have the same cargo carrying capacity. The paper presents parallel savings algori...
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作者：BEAN, JC; BIRGE, JR; MITTENTHAL, J; NOON, CE
作者单位：Rensselaer Polytechnic Institute; University of Tennessee System; University of Tennessee Knoxville
摘要：This paper considers the rescheduling of operations with release dates and multiple resources when disruptions prevent the use of a preplanned schedule. The overall strategy is to follow the preschedule until a disruption occurs. After a disruption, part of the schedule is reconstructed to match up with the preschedule at some future time. Conditions are given for the optimality of this approach. A practical implementation is compared with the alternatives of preplanned static scheduling and m...
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作者：EMMONS, H; BURNS, RN
作者单位：Queens University - Canada
摘要：A work force includes workers of m types. The worker categories are ordered, with type-1 workers the most highly qualified, type-2 the next, and so on. If the need arises, a type-k worker is able to substitute for a worker of any type j > k (k = 1,...,m - 1). For 7-day-a-week operation, daily requirements are for at least D(k) workers of type-k or better, of which at least d(k) must be precisely type-k. Formulas are given to find the smallest number and most economical mix of workers, assuming...
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作者：KELLA, O
摘要：We consider a machine that works constantly and produces two types of fluid products, one type of product at a time. Whenever there is a positive amount of both types of products, the products are mixed immediately and shipped away. Whenever mixing is infeasible the product that is currently being produced accumulates inventory. The goal is to minimize the long-run average as well as the discounted costs of running such an operation. Inventory incurs a linear holding cost for each type of prod...
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作者：GREEN, L; KOLESAR, P; SVORONOS, A
摘要：We examine the effects of nonstationarity on the performance of multiserver queueing systems with exponential service times and sinusoidal Poisson input streams. Our primary objective is to determine when and how a stationary model may be used as an approximation for a nonstationary system. We focus on a particular question: How nonstationary can an arrival process be before a simple stationary approximation fails? Our analysis reveals that stationary models can seriously underestimate delays ...
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作者：JONEJA, D
摘要：In a multi-echelon assembly system, each production stage has inputs from a number of preceding stages, and supplies at most one succeeding stage. The product of the final stage is used to satisfy external demand in discrete time. There are fixed setup costs and linear inventory holding costs at each stage. The objective is to minimize the cost of operating the system over a finite time horizon. We consider the common case of nonstationary demands, and propose an extremely fast and simple sing...
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作者：MORRISON, DG; SCHMITTLEIN, DC
作者单位：University of Pennsylvania
摘要：How to combine expert opinions is an issue that has many aspects and even more answers. The problem addressed here is the incremental information an additional expert brings when he or she is correlated with the existing experts. R. T. Clemen and R. L. Winkler derive an algebraic formula that gives the surprising answer-usually very little. In this paper, we provide the geometrical intuition behind the Clemen and Winkler result. We also show how the Clemen and Winkler formula breaks down (i.e....
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作者：WHITE, JA
摘要：This paper, which is based on the Omega Rho lecture given at the 1990 ORSA/TIMS meeting in Philadelphia, states the author's necessary and sufficient conditions for effective OR/MS. Then it describes the changing character of this field, considers some opportunities for it, addresses some human resources concerns facing it, and offers a view of what it will do in the 21st century. After addressing some concerns about the higher education culture, it then provides some conclusions about the fut...
