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作者：Bramel, J; Goyal, S; Zipkin, P
作者单位：Columbia University; Duke University
摘要：We investigate multiproduct, multilocation production root distribution networks with deterministic, stationary demands. Most research on such systems assumes zero leadtimes. Methods using fixed reorder intervals that are power-of-two multiples of a base planning period have proved to be very successful for such systems. The same methods apply to networks with positive leadtimes, provided the leadtimes are balanced in a specific sense. We explore networks with general, unbalanced leadtimes. A ...
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作者：Hoffman, R; Ball, MO
作者单位：University System of Maryland; University of Maryland College Park; University System of Maryland; University of Maryland College Park
摘要：Both the single-airport ground-holding problem (GH) and the multi-airport ground-holding problem can be extended by the addition of banking constraints to accommodate the hubbing operations of major airlines. These constraints enforce the desire of airlines to land certain groups of flights, called banks, within fixed time windows, thus preventing the propagation of delays throughout their entire operation. GH can be formulated as a transportation problem and readily solved. But in the presenc...
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作者：Amiouny, SV; Bartholdi, JJ; Vate, JH
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：We develop heuristics for problem that models the static balancing of turbine fans: load point masses at regularly spaced positions on the periphery of a circle so that the residual unbalance about the center-which corresponds to the axis of rotation of the fan-is as small as possible. We give worst-case guarantees for our heuristics in terms of residual unbalance. For the case of an even number of blades, we show that one of our heuristics provides the same worst-case guarantee (with respect ...
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作者：Barnhart, C; Jin, H; Vance, PH
作者单位：Massachusetts Institute of Technology (MIT); Emory University
摘要：In this study, we formulate the railroad blocking problems as a network design problem with maximum degree and flow constraints on the nodes and propose a heuristic Lagrangian relaxation approach to solve the problem. The new approach decomposes the complicated mixed integer programming problem into two simple subproblems so that the storage requirement and computational effort are greatly reduced. A set of inequalities are added to one subproblem to tighten the lower bounds and facilitate gen...
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作者：Xia, CH; Shanthikumar, JG; Glynn, PW
作者单位：International Business Machines (IBM); IBM USA; University of California System; University of California Berkeley; University of California System; University of California Berkeley; Stanford University
摘要：Consider a flow shop with M machines in series, through which a set of jobs are to be processed. All jobs have the same routing, and they have to be processed in the same order on each of the machines. The objective is to determine such an order of the jobs, often referred to as a permutation schedule, so as to minimize the total completion time of all jobs on the final machine. We show that when the processing times are statistically exchangeable across machines and independent across jobs, t...
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作者：Dawande, MW; Hooker, JN
作者单位：International Business Machines (IBM); IBM USA; Carnegie Mellon University
摘要：A new method of sensitivity analysis for mixed integer/linear programming (MILP) is derived from the idea of inference duality. The inference dual of an optimization problem asks how the optimal value can be deduced from the constraints. In MILP, a deduction based on the resolution method of theorem proving can be obtained from the branch-and-cut tree that solves the primal problem. One can then investigate which perturbations of the problem leave this proof intact. On this basis it is shown t...
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作者：Anily, S; Bramel, J
作者单位：Tel Aviv University; Columbia University
摘要：We consider the problem of servicing a number of objects in a discrete time environment. In each period, we may select an object that will receive a service in the period. Each time an object is serviced, we incur a servicing; cost dependent on the time since the object's last service. Problems of this type appear in many contexts, e.g., multiproduct lot-sizing, machine maintenance, and several problems in telecommunications. We assume that at most one object can be serviced in a given period....
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作者：Cheung, KL; Hausman, WH
作者单位：Hong Kong University of Science & Technology; Stanford University
摘要：This paper studies a continuous review two-echelon inventory system with a supplier serving multiple retailers. Each location uses a decentralized (Q,R) policy based on installation stocks. Each retailer may set a unique reorder quantity as a multiple of a basic packaging size Q. The supplier, in turn, adopts a similar batch replenishment policy. Our objective is to derive the exact steady-state performance for the supplier. We show that the inventory position at the supplier can be easily cha...
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作者：Dawson, CS; McCallum, CJ Jr; Murphy, RB; Wolman, E
作者单位：George Mason University
摘要：This historical account of operations research at Bell Laboratories was drafted in the late 1970s when the authors were part of the Operations Research Center within Bell Laboratories at AT & T; it has not previously appeared in the open literature. We have added a few references to later publications that describe particular aspects of the period covered. Discussions of technological practices and organizational arrangements expressed in the present tense represent a viewpoint of about 1980, ...
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作者：Bashyam, TCA
摘要：We examine two competing technologies for delivering business information to professional subscribers: first, a package service that delivers information using physical media, such as CD-ROMs; second an online service that allows subscribers to access information over online networks. We model the information services market as a duopoly. where each information service provider is equipped with either packaged or online information delivery technology. They compete for potential subscribers ch...
