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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...
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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：Cui, Tingting; Ouyang, Yanfeng; Shen, Zuo-Jun Max
作者单位：University of California System; University of California Berkeley; University of Illinois System; University of Illinois Urbana-Champaign
摘要：Reliable facility location models consider unexpected failures with site-dependent probabilities, as well as possible customer reassignment. This paper proposes a compact mixed integer program (MIP) formulation and a continuum approximation (CA) model to study the reliable uncapacitated fixed charge location problem (RUFL), which seeks to minimize initial setup costs and expected transportation costs in normal and failure scenarios. The MIP determines the optimal facility locations as well as ...
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作者：Kwon, H. Dharma
作者单位：University of Illinois System; University of Illinois Urbana-Champaign
摘要：Even in the face of deteriorating and highly volatile demand, firms often invest in, rather than discard, aging technologies. To study this phenomenon, we model the firm's profit stream as a Brownian motion with negative drift. At each point in time, the firm can continue operations, or it can stop and exit the project. In addition, there is a one-time option to make an investment that boosts the project's profit rate. Using stochastic analysis, we show that the optimal policy always exists an...
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作者：Taskin, Z. Caner; Smith, J. Cole; Romeijn, H. Edwin; Dempsey, James F.
作者单位：State University System of Florida; University of Florida; University of Michigan System; University of Michigan; State University System of Florida; University of Florida
摘要：We consider a problem dealing with the efficient delivery of intensity modulated radiation therapy (IMRT) to individual patients. IMRT treatment planning is usually performed in three phases. The first phase determines a set of beam angles through which radiation is delivered, followed by a second phase that determines an optimal radiation intensity profile (or fluence map). This intensity profile is selected to ensure that certain targets receive a required amount of dose while functional org...
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作者：Caro, Felipe; Gallien, Jeremie
作者单位：University of California System; University of California Los Angeles; Massachusetts Institute of Technology (MIT)
摘要：Working in collaboration with Spain-based retailer Zara, we address the problem of distributing, over time, a limited amount of inventory across all the stores in a fast-fashion retail network. Challenges specific to that environment include very short product life cycles, and store policies whereby an article is removed from display whenever one of its key sizes stocks out. To solve this problem, we first formulate and analyze a stochastic model predicting the sales of an article in a single ...
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作者：Chen, Wenqing; Sim, Melvyn; Sun, Jie; Teo, Chung-Piaw
作者单位：National University of Singapore; National University of Singapore
摘要：We review and develop different tractable approximations to individual chance-constrained problems in robust optimization on a variety of uncertainty sets and show their interesting connections with bounds on the conditional-value-at-risk (CVaR) measure. We extend the idea to joint chance-constrained problems and provide a new formulation that improves upon the standard approach. Our approach builds on a classical worst-case bound for order statistics problems and is applicable even if the con...
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作者：Gurvich, Itai; Whitt, Ward
作者单位：Northwestern University; Columbia University
摘要：Motivated by telephone call centers, we study large-scale service systems with multiple customer classes and multiple agent pools, each with many agents. To minimize staffing costs subject to service-level constraints, where we delicately balance the service levels (SLs) of the different classes, we propose a family of routing rules called fixed-queue-ratio (FQR) rules. With FQR, a newly available agent next serves the customer from the head of the queue of the class (from among those he is el...
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作者：Muharremoglu, Alp; Yang, Nan
作者单位：Columbia University; Cornell University
摘要：We study single and multistage inventory systems with stochastic lead times. We study a class of stochastic lead time processes, which we refer to as exogenous lead times. This class of lead time processes includes as special cases all lead time models from existing literature (such as Kaplan's lead times with no order crossing or independent and identically distributed lead times with order crossing, among others) but is a substantially broader class. For a system with an exogenous lead time ...
