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作者：Panagiotidou, Sofia; Tagaras, George
作者单位：Aristotle University of Thessaloniki
摘要：This paper focuses on the close relationship between statistical process control and preventive maintenance (PM) of manufacturing equipment. The context is very general: a production process that is characterized by multiple distinct operational states and a failure state. The operational states differ in terms of operational/quality costs and/or the proneness to complete failure. The times of shift from the normal operational state to an inferior one and the times to failure are random variab...
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作者：Barth, Wolfgang; Manitz, Michael; Stolletz, Raik
作者单位：University of Cologne; Technical University of Denmark
摘要：In this paper, we analyze the performance of call centers of financial service providers with two levels of support and a time-dependent overflow mechanism. Waiting calls from the front-office queue flow over to the back office if a waiting-time limit is reached and at least one back-office agent is available. The analysis of such a system with time-dependent overflow is reduced to the analysis of a continuous-time Markov chain with state-dependent overflow probabilities. To approximate the sy...
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作者：Mehrotra, Vijay; Ozluk, Ozguer; Saltzman, Robert
作者单位：University of San Francisco; California State University System; San Francisco State University
摘要：For nearly all call centers, agent schedules are typically created several days or weeks before the time that agents report to work. After schedules are created, call center resource managers receive additional information that can affect forecasted workload and resource availability. In particular, there is significant evidence, both among practitioners and in the research literature, suggesting that actual call arrival volumes early in a scheduling period (typically an individual day or week...
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作者：Wang, Ping; Zinn, Walter; Croxton, Keely L.
作者单位：Tianjin University; University System of Ohio; Ohio State University
摘要：Determining appropriate inventory levels has been a subject of interest for both researchers and practitioners. Standard practice is to treat lead time demand as a random sum of random numbers and rely on established probability theory to calculate both reorder point and safety stock levels. A key assumption in these calculations, however, is that lead time and demand are not correlated. In this paper, we first explore situations where this assumption is untrue and then develop equations to de...
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作者：Salmeron, Javier; Apte, Aruna
作者单位：United States Department of Defense; United States Navy; Naval Postgraduate School; United States Department of Defense; United States Navy; Naval Postgraduate School
摘要：A key strategic issue in pre-disaster planning for humanitarian logistics is the pre-establishment of adequate capacity and resources that enable efficient relief operations. This paper develops a two-stage stochastic optimization model to guide the allocation of budget to acquire and position relief assets, decisions that typically need to be made well in advance before a disaster strikes. The optimization focuses on minimizing the expected number of casualties, so our model includes first-st...
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作者：Fruchter, Gila E.; Mantrala, Murali K.
作者单位：Bar Ilan University; University of Missouri System; University of Missouri Columbia
摘要：This paper focuses on the proactive planning of a partial switch of a prescription (Rx) drug brand to over-the-counter (OTC) status within the former's patent-protected life. The planning issues are whether and when to make this switch from the single-status Rx drug phase to the dual-status Rx+OTC phase with or without the grant of a 3-year market exclusivity period for the OTC drug by the US Food and Drug Administration. We formulate an optimal control problem that leads to a two-phase optimi...
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作者：Diaz, Rafael; Ardalan, Ali
作者单位：Old Dominion University; Old Dominion University
摘要：Recent advances in approaches and production technologies for the production of goods and services have made just-in-time (JIT) a strong alternative for use in intermittent and small batch production systems, especially when time-based competition is the norm and a low inventory is a must. However, the conventional JIT system is designed for mass production with a stable master production schedule. This paper suggests supplementing the information provided by production kanbans with informatio...
