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作者：Chand, S; Moskowitz, H; Novak, A; Rekhi, I; Sorger, G
作者单位：University of Vienna
摘要：Management of process improvement activities is an essential part of the manufacturing strategy of a firm to remain globally competitive in the long run. This paper considers a manufacturing environment where process improvement activities require use of the productive capacity of the firm in addition to other investments. Thus the firm must allocate its productive capacity between production activities and improvement activities. The output of production activities is used to meet customer de...
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作者：Massey, WA; Whitt, W
摘要：In this paper we consider the M(t)/G/s/0 model, which has s servers in parallel, no extra waiting space, and i.i.d. service times that are independent of a nonhomogeneous Poisson arrival process. Arrivals finding all servers busy are blocked (lost). We consider approximations for the average blocking probabilities over subintervals (e.g., an hour when the expected service time is five minutes) obtained by replacing the nonstationary arrival process over that subinterval by a stationary arrival...
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作者：Kimura, T
摘要：This paper develops a transform-free approximation for the steady-state queue-length distribution in an M/G/s queue with finite waiting spaces. The approximation is obtained by using a conservation law and some heuristics. It is shown that the approximation is exact for the cases with either no extra waiting space, exponential service-time distribution, or a certain two-parameter family of service-time distributions. It is also shown that the approximation has the same light-traffic properties...
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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...
