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作者：Federgruen, A; Katalan, Z
作者单位：University of Pennsylvania
摘要：We characterize the impact of the means and distributions of setup times in polling systems. Starting with cyclic systems with exhaustive service, we show that the vector of average setup times affects the complete distribution of waiting times and queue sizes only via its sum. In addition, all moments of all waiting times and queue sizes are reduced if the higher order moments of one or more of the setup times is reduced while maintaining their means. We also obtain a fundamental decompositio...
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作者：Wu, YJ; Fuller, JD
作者单位：University of Waterloo
摘要：This paper presents a new equilibrium-seeking algorithm, called the decoupling algorithm, for calculation of multiperiod equilibrium of supplies and demands when demand has a geometric distributed lag (GDL) structure and supply is represented by a linear process submodel. The new algorithm is required because it may be difficult to obtain the equilibrium by a diagonalization algorithm such as PIES. In each step of the decoupling algorithm, a modified GDL equilibrium model, the ''decoupled subm...
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作者：Chen, SX; Lambrecht, M
作者单位：KU Leuven
摘要：This paper considers the stochastic, single-item, periodic review inventory problem. Most importantly we assume a finite production capacity per period and a production cost function containing a fixed (as well as a variable) component. With stationary data, a convex expected holding and shortage cost function, we show that generally the modified (s, S) policy is not optimal to the finite horizon problems. The optimal policy does, however, show a systematic pattern which we call the X-Y band s...
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作者：Elimam, AA; Girgis, M; Kotob, S
作者单位：Kuwait Institute for Scientific Research
摘要：A highly speculative parallel stock market, called Souk al-Manakh, emerged in Kuwait in 1980-81. Due to the absence of checks and balances, the default of one trader led to the collapse of al-Manakh in 1982. This triggered a major financial national crisis as debts arising from the crash reached a staggering US $94 billion, or more than four times Kuwait's GDP. The crash precipitated an economic recession, business failures, and more bankruptcies among traders. it was impossible for the govern...
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作者：MacLellan, JI; Martell, DL
摘要：The Ontario Ministry of Natural Resources (OMNR) operates a fleet of nine CL-215 airtankers for forest fire control. The aircraft are based at a small number of airports that serve as home bases, from which they are deployed to a larger set of airports that serve as initial attack bases for fire fighting operations each day. We helped regional fire managers derive subjective airtanker deployment rules that specified how many airtankers were to be deployed al each initial attack base each day. ...
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作者：Rydell, CP; Caulkins, JP; Everingham, SS
作者单位：Carnegie Mellon University
摘要：This paper presents a model that estimates the relative cost-effectiveness of four cocaine-control programs: three ''supply control'' programs (source-country control, interdiction, and domestic enforcement) and a ''demand control'' program (treating heavy users). Treatment emerges as by far the most cost-effective, and sensitivity analyses show that this result is very robust.
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作者：Hu, CP; Lovejoy, WS; Shafer, SL
作者单位：University of Michigan System; University of Michigan
摘要：In drug therapy, efficient dosage policies are needed to maintain drug concentrations at target. The relationship between the concentration of a drug and the dosages is often described by compartment models in which the parameters are unknown, although prior knowledge may be available and can be updated after blood samples are taken during the therapy. In this paper we define some tractable policies for adaptive control of drug concentrations in compartment models and compare their performance...
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作者：Jin, HH; Batta, RJ; Karwan, MH
作者单位：State University of New York (SUNY) System; University at Buffalo, SUNY
摘要：This paper considers two new decision-making problems in the context of transporting hazardous materials (I-IM). These problems are motivated by the fact that many practical situations only have a finite number of shipments of I-IM to be made and that shipments are likely to be suspended after a threshold number of accidents. Both problems are nonlinear, constrained shortest path problems. Exact solution methods are proposed and computational results are reported for the case where the thresho...
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作者：Glasserman, P
摘要：We consider the problem of allocating production capacity among multiple items, assuming that a fixed proportion of overall capacity can be dedicated exclusively to the production of each item. Given a capacity allocation, production of each item follows a base-stock policy, i.e., each demand triggers a replenishment order to restore safety stocks to target levels. We present procedures for choosing base-stock levels and capacity allocations that are asymptotically optimal. Our objective is to...
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作者：Ng, SM
摘要：Group technology plays an important role in the design of an automated manufacturing system. The ideal situation is to partition the machines into machine cells and the parts into part families so that each machine cell together with the part family for the cell is independent of the rest of the system. We will give a characterization of the independent cells for an arbitrary manufacturing system. An efficient algorithm to identify these independent cells will also be discussed. An effective p...
