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作者：HLYNKA, M; STANFORD, DA; POON, WH; WANG, T
作者单位：Western University (University of Western Ontario); University of Alberta
摘要：We consider a queueing system with two servers, each with its own queue. The interarrival times are generally distributed. The service time for each server is exponentially distributed but the rates may be different. No jockeying between the two queues is allowed. We consider situations in which a smart customer can delay joining a queue until some arrivals or service departures have been observed. All other customers join the shortest queue. We find conditions under which the smart customer c...
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作者：GEORGIADIS, L; VINIOTIS, I
作者单位：North Carolina State University
摘要：We consider a multiclass GI/G/I queueing system, operating under an arbitrary work-conserving scheduling policy pi. We derive an invariance relation for the Cesaro sums of waiting times under pi, which does not require the existence of limits of the Cesaro sums. This allows us to include important classes in the set of admissible policies such as time-dependent and adaptive policies. For these classes of policies, ergodicity is not known a priori and may not even exist. Therefore, the classica...
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作者：ADVE, VS; NELSON, R
作者单位：International Business Machines (IBM); IBM USA
摘要：We consider an M/G/I queue with feedback, in which customers, after receiving service, either return to the tail of the queue or depart the system, according to some feedback policy. We derive simple expressions for the expected response time for feedback policies that include Bernoulli feedback and feeding back a fixed number of times. Our results reveal some interesting and nonintuitive properties of the behavior of such feedback policies when the coefficient of variation of service time is ...
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作者：NEMHAUSER, GL
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：In the last decade, new advances in algorithms have been as important as the impressive advances in computer technology. Using the new interior-point algorithms and advanced implementations of simplex methods, we can now solve linear programs with more than one million variables and thousands of constraints. Preprocessing and polyhedral theory have yielded at least an order of magnitude improvement in branch-and-bound algorithms for solving mixed integer programs. Moreover, these algorithmic a...
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作者：SADRIAN, AA; YOON, YS
摘要：Emergence of a new discount pricing schedule called Business Volume Discount becomes a major obstacle for procurement managers in finding the best purchasing strategy. In the context of business volume discount, a supplier offers discounts on total dollar amount of sales volume, not on the quantity or variety of the products purchased from the supplier. This paper describes a Procurement Decision Support System (PDSS) that has been successfully implemented to improve the purchasing activities ...
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作者：KREIMER, J; MEHREZ, A
作者单位：Ben-Gurion University of the Negev; University System of Ohio; Kent State University; Kent State University Kent; Kent State University Salem; University System of Ohio; Ohio University; McMaster University
摘要：We obtain an optimal operation policy for a general n-server (channel, machine) stand-by system involving preventive maintenance and operating in real time. We show that such a policy is achieved by successive total use of each server capacity, and does not depend on the arrival pattern of processed data and task duration. We show also that this policy is optimal for any finite, initial period of time, and not only in the sense of long-run availability. The analysis is performed in two stages:...
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作者：ROTHKOPF, MH
作者单位：Rutgers University System; Rutgers University New Brunswick
摘要：The OR Practice Section of Operations Research is approaching its tenth anniversary. This note ''amines and interprets the nature of the papers that it has attracted and argues that they suggest vigor in the practice of operations research.
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作者：REISMAN, A; XU, XM
摘要：This paper reviews the record of OR/MS applications to library management. Although libraries constitute a major factor in both the public and the private (not-for-profit) sectors, OR/MS has not fulfilled its potential in enhancing the cost effectiveness of library systems.
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作者：RIBEIRO, CC; SOUMIS, F
作者单位：Universite de Montreal; Universite de Montreal; Polytechnique Montreal
摘要：We give a new formulation to the multiple-depot vehicle scheduling problem as a set partitioning problem with side constraints, whose continuous relaxation is amenable to be solved by column generation. We show that the continuous relaxation of the set partitioning formulation provides a much tighter lower bound than the additive bound procedure previously applied to this problem. We also establish that the additive bound technique cannot provide tighter bounds than those obtained by Lagrangia...
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作者：BOYD, EA
摘要：A technique for generating cutting planes for integer programs is introduced that is based on the ability to optimize a linear function on a polyhedron rather than explicit knowledge of the underlying polyhedral structure of the integer program. The theoretical properties of the cuts and their relationship to Lagrangian relaxation are discussed, the cut generation procedure is described, and computational results are presented.
