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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....
