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作者：Bertsimas, Dimitris; Lulli, Guglielmo; Odoni, Amedeo
作者单位：Massachusetts Institute of Technology (MIT); Massachusetts Institute of Technology (MIT); University of Milano-Bicocca; Massachusetts Institute of Technology (MIT)
摘要：This paper presents a new integer programming (IP) model for large-scale instances of the air traffic flow management (ATFM) problem. The model covers all the phases of each flight-i.e., takeoff, en route cruising, and landing-and solves for an optimal combination of flow management actions, including ground-holding, rerouting, speed control, and airborne holding on a flight-by-flight basis. A distinguishing feature of the model is that it allows for rerouting decisions. This is achieved throu...
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作者：Baldacci, Roberto; Bartolini, Enrico; Mingozzi, Aristide; Valletta, Andrea
作者单位：University of Bologna; University of Bologna; University of Bologna
摘要：This paper presents an exact algorithm for solving strategic and tactical multiperiod vehicle routing problems that can be modeled as period vehicle routing problems (PVRPs). The PVRP is defined on a time horizon of several days and consists of assigning appropriate combinations of delivery to customers and designing a set of delivery routes for every day of the planning period. The objective is to service all customers assigned to each day minimizing the overall routing cost. This paper descr...
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作者：Lane, David C.
作者单位：University of London; London School Economics & Political Science
摘要：This paper has two aims. First, to present cases in which scientists developed a defensive system for their homeland: Blackett and the air defense of Britain in WWII, Forrester and the SAGE system for North America in the Cold War, and Archimedes' work defending Syracuse during the Second Punic War. In each case the historical context and the individual's other achievements are outlined, and a description of the contribution's relationship to OR/MS is given. The second aim is to consider some ...
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作者：Gemici-Ozkan, Banu; Wu, S. David; Linderoth, Jeffrey T.; Moore, Jeffry E.
作者单位：Lehigh University; University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison; Lehigh University
摘要：We introduce a decision-support framework for the research and development (R&D) portfolio selection problem faced by a major U. S. semiconductor manufacturer. R&D portfolio selection is of critical importance to high-tech operations such as semiconductors and pharmaceuticals, because it determines the blend of technological development the firm must invest in its R&D resources. This R&D investment leads to differentiating technologies that drive the firm's market position. We developed a gene...
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作者：Dobson, Gregory; Lee, Hsiao-Hui; Pinker, Edieal
作者单位：University of Rochester; University of Connecticut
摘要：Many intensive care units (ICUs) face overcrowding. One response to this overcrowding is to bump ICU patients to other departments of the hospital to make room for new patient arrivals. Such bumping clearly has the potential to reduce quality of care. In this paper we develop a stochastic model of a single ICU with patient bumping. The purpose of this model is to enable planners to predict performance, in terms of bumping, under differing arrival patterns and capacity. We develop a Markov chai...
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作者：Shin, Hyoduk; Tunca, Tunay I.
作者单位：Northwestern University; Stanford University
摘要：We study the effect of downstream competition on incentives for demand forecast investments in supply chains. We show that with common pricing schemes, such as wholesale price or two-part tariffs, downstream firms under Cournot competition overinvest in demand forecasting. Analyzing the determinants of overinvestment, we demonstrate that under wholesale price contracts and two-part tariffs, total demand forecast investment can be very significant, and as a result, the supply chain can suffer s...
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作者：Glasserman, Paul; Liu, Zongjian
作者单位：Columbia University; Columbia University
摘要：The likelihood ratio method (LRM) is a technique for estimating derivatives of expectations through simulation. LRM estimators are constructed from the derivatives of probability densities of inputs to a simulation. We investigate the application of the likelihood ratio method for sensitivity estimation when the relevant densities for the underlying model are known only through their characteristic functions or Laplace transforms. This problem arises in financial applications, where sensitivit...
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作者：Fourer, Robert; Ma, Jun; Martin, Kipp
作者单位：Northwestern University; University of Chicago
摘要：We describe a research project to design a distributed optimization environment in which solvers, modeling languages, registries, analyzers, and simulation engines can be implemented as services and utilities under a unified framework. Our work, which we call optimization services or OS, defines standards for all activities necessary to support decentralized optimization on the Internet: representation of optimization instances, results, and solver options; communication between clients and so...
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作者：Vaidyanathan, Balachandran; Ahuja, Ravindra K.
作者单位：State University System of Florida; University of Florida
摘要：The objective of the classical minimum cost flow problem is to send units of a good that reside at one or more points in a network (sources or supply nodes) with arc capacities to one or more other points in the network (sinks or demand nodes), incurring minimum cost. We develop fast algorithms for previously unstudied specially structured minimum cost flow problems that have applications in many areas, such as locomotive and airline scheduling, repositioning of empty rail freight cars, highwa...
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作者：Cadenillas, Abel; Lakner, Peter; Pinedo, Michael
作者单位：University of Alberta; University of Alberta; New York University
摘要：Motivated by empirical observations, we assume that the inventory level of a company follows a mean-reverting process. The objective of the management is to keep this inventory level as close as possible to a given target; there is a running cost associated with the difference between the actual inventory level and the target. If inventory deviates too much from the target, management may perform an intervention in the form of either a purchase or a sale of an amount of the goods. There are fi...
