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作者：Stolyar, Alexander L.; Tezcan, Tolga
作者单位：AT&T; University of Rochester
摘要：We consider a general parallel server system model with multiple customer classes and several flexible multiserver pools, in the many-server asymptotic regime where the input rates and server pool sizes are scaled up linearly to infinity. Service of a customer brings a constant reward, which depends on its class. The objective is to maximize the long-run reward rate. Our primary focus is on overloaded systems. Unlike in the case when the system is not overloaded, where the main decision is how...
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作者：Contreras, Ivan; Cordeau, Jean-Francois; Laporte, Gilbert
作者单位：Concordia University - Canada; Universite de Montreal; Universite de Montreal; HEC Montreal; Universite de Montreal
摘要：This paper describes an exact algorithm capable of solving large-scale instances of the well-known uncapacitated hub location problem with multiple assignments. The algorithm applies Benders decomposition to a strong path-based formulation of the problem. The standard decomposition algorithm is enhanced through the inclusion of several features such as the use of a multicut reformulation, the generation of strong optimality cuts, the integration of reduction tests, and the execution of a heuri...
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作者：Steiner, George; Zhang, Rui
作者单位：McMaster University
摘要：There are many situations in supply chain scheduling when the supplier finds it impossible to meet the promised due dates for some orders. We present a model for the rescheduling of orders with simultaneous assignment of attainable revised due dates to minimize due date escalation and tardiness penalties for the supplier. We show that the problem is equivalent to minimizing the total tardiness with rejection with respect to the original due dates. We prove that the problem is NP-hard and prese...
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作者：Yan, Xinghao; Zhao, Hui
作者单位：Western University (University of Western Ontario); University Western Ontario Hospital; Purdue University System; Purdue University
摘要：We study the information asymmetry issues in a decentralized inventory-sharing system consisting of a manufacturer and two independent retailers, who privately hold demand information, noncooperatively place their orders, but cooperatively share inventories with each other. We find that although the manufacturer needs retailers' mean demand and standard deviation for her wholesale price decision, each retailer only needs to know the other retailer's demand standard deviation for his order quan...
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作者：Toth, Sandor F.; Haight, Robert G.; Rogers, Luke W.
作者单位：University of Washington; University of Washington Seattle; United States Department of Agriculture (USDA); United States Forest Service
摘要：Urban growth compromises open space and ecosystem functions. To mitigate the negative effects, some agencies use reserve selection models to identify conservation sites for purchase or retention. Existing models assume that conservation has no impact on nearby land prices. We propose a new integer program that relaxes this assumption via adaptive cost coefficients. Our model accounts for the two key land price feedbacks that arise in markets where conservation competes with development: the am...
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作者：Johari, Ramesh; Tsitsiklis, John N.
作者单位：Stanford University; Massachusetts Institute of Technology (MIT)
摘要：We consider a model where a finite number of producers compete to meet an infinitely divisible but inelastic demand for a product. Each firm is characterized by a production cost that is convex in the output produced, and firms act as profit maximizers. We consider a uniform price market design that uses supply function bidding: firms declare the amount they would supply at any positive price, and a single price is chosen to clear the market. We are interested in evaluating the impact of price...
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作者：Chou, Mabel C.; Chua, Geoffrey A.; Teo, Chung-Piaw; Zheng, Huan
作者单位：National University of Singapore; Nanyang Technological University; Shanghai Jiao Tong University
摘要：We examine how to design a flexible process structure for a production system to match supply with demand more effectively. We argue that good flexible process structures are essentially highly connected graphs, and we use the concept of graph expansion (a measure of graph connectivity) to achieve various insights into this design problem. Whereas existing literature on process flexibility has focused on the expected performance of process structure, we analyze in this paper the worst-case per...
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作者：Ibrahim, Rouba; Whitt, Ward
作者单位：McGill University; Columbia University
摘要：We develop new, improved real-time delay predictors for many-server service systems with a time-varying arrival rate, a time-varying number of servers, and customer abandonment. We develop four new predictors, two of which exploit an established deterministic fluid approximation for a many-server queueing model with those features. These delay predictors can be used to make delay announcements. We use computer simulation to show that the proposed predictors outperform previous predictors.
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作者：Kwon, H. Dharma; Lippman, Steven A.
作者单位：University of Illinois System; University of Illinois Urbana-Champaign; University of California System; University of California Los Angeles
摘要：We study the impact of learning on the optimal policy and the time-to-decision in an infinite-horizon Bayesian sequential decision model with two irreversible alternatives: exit and expansion. In our model, a firm undertakes a small-scale pilot project to learn, via Bayesian updating, about the project's profitability, which is known to be in one of two possible states. The firm continuously observes the project's cumulative profit, but the true state of the profitability is not immediately re...
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作者：Oezaltin, Osman Y.; Prokopyev, Oleg A.; Schaefer, Andrew J.; Roberts, Mark S.
作者单位：University of Waterloo; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
摘要：Seasonal influenza is a major public health concern, and the first line of defense is the flu shot. Antigenic drifts and the high rate of influenza transmission require annual updates to the flu shot composition. The World Health Organization recommends which flu strains to include in the annual vaccine, based on surveillance and epidemiological analysis. There are two critical decisions regarding the flu shot design. One is its composition; currently, three strains constitute the flu shot, an...
