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作者：Jain, S; Johnson, ME; Safai, F
作者单位：Vanderbilt University; Hewlett-Packard
摘要：We develop a model and solution algorithm for sequencing production on a flexible assembly line. The model incorporates the practical considerations of printed circuit board (PCB) assembly where the goal is to reduce the time spent in setup. We discuss the practical implementation problems of integrating optimization software on the shop floor-both from an operations research and systems perspective. We describe Hewlett-Packard's successful use of the software and the limitations of production...
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作者：Barnhart, C; Schneur, RR
摘要：Express shipment service requires that shipments be picked up and delivered within specified time intervals (e.g., 24 hours, 48 hours or 3-5 days). In this paper, we describe the express shipment service design problem faced by a carrier and present a model and column generation approach for its solution. Our approach can find near optimal air service designs for a fixed aircraft fleet or for a fleet of unspecified size and make-up. In the latter case, the service design, fleet size and fleet ...
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作者：Revelle, CS; Laporte, G
作者单位：Universite de Montreal
摘要：The plant location problem has been studied for many years. Yet, a number of important real world issues and variants have not been investigated or resolved and merit further attention and research. This paper describes new statements of the problem (1) with new and different objectives, (2) with multiple products and multiple machines in which new models of production are considered, and (3) with spatial interactions.
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作者：Balas, E; Carrera, MC
摘要：We discuss a branch and bound algorithm for set covering, whose centerpiece is a new integrated upper bounding/lower bounding procedure called dynamic subgradient optimization (DYNSGRAD). This new procedure, applied to a Lagrangean dual at every node of the search tree, combines the standard subgradient method with primal and dual heuristics that interact to change the Lagrange multipliers and tighten the upper and lower bounds, fix variables, and periodically restate the Lagrangean itself. Ex...
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作者：Chen, B; Glass, CA; Potts, CN; Strusevich, VA
作者单位：University of Southampton; University of Greenwich
摘要：This paper considers the problem of sequencing n jobs in a three-machine flow shop with the objective of minimizing the makespan, which is the completion time of the last job. An O(n log n) time heuristic that is based on Johnson's algorithm is presented. It is shown to generate a schedule with length at most 5/3 times that of an optimal schedule, thereby reducing the previous best available worst-case performance ratio of 2. An application to the general flow shop is also discussed.
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作者：Ramudhin, A; Bartholdi, JJ; Calvin, JM; Vate, JHV; Weiss, G
作者单位：Laval University; University System of Georgia; Georgia Institute of Technology
摘要：We study a two-machine flowshop in which all processing times are independently and identically distributed, with values known to the scheduler. We are able to describe in detail the expected behavior of the flowshop under optimal and heuristic schedules. Our results suggest that minimizing makespan might be a superfluous objective: random schedules are easier to construct and require significantly less intermediate storage between the machines; moreover, they are known to be asymptotically op...
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作者：Edirisinghe, NCP
摘要：This paper develops new bounds on the expectation of a convex-concave saddle function of a random vector with compact domains. The bounds are determined by replacing the underlying distribution by unique discrete distributions, constructed using second-order moment information. The results extend directly to new second moment lower bounds in closed-form for the expectation of a convex function. These lower bounds are better than Jensen's bound, the only previously known lower bound for the con...
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作者：Campbell, JF
摘要：Hub facilities serve as switching and transshipment points in transportation and communication networks. Hub networks concentrate flows on the hub-to-hub links and benefit from economies of scale in interhub transportation. Most hub location research has focused on problems where each origin/destination is allocated to a single hub. However, multiple allocation to more than one hub is necessary to minimize total transportation costs. This paper defines ap-hub median, analogous to ap-median, an...
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作者：Harrison, JM; Pich, MT
作者单位：INSEAD Business School
摘要：The QNET method for two-moment analysis of multiclass open networks is extended to allow complex workstations of various types. For example, the extension described here allows one to treat stations where several unreliable machines are tended by a small number of repair technicians, or stations where several machines that require setups are tended by a small number of operators. To illustrate the general concepts, a four-station manufacturing example is discussed in detail. In the QNET method...
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作者：Cheung, RK; Powell, WB
作者单位：Princeton University; Iowa State University
摘要：We consider the class of multistage dynamic networks with random are capacities a framework that is well suited to model dynamic fleet management problems. We propose a successive convex approximation approach that produces an approximation to the expected recourse function which captures the future effects of current decisions under uncertainty. This method decomposes the network in each stage into tree subproblems, whose expected recourse functions are easy to obtain. We also compare this me...
