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作者：Moinzadeh, K; Aggarwal, PK
作者单位：William & Mary
摘要：In this paper we study a (S-1, S) type multiechelon inventory system where all the stocking locations have the option to replenish their inventory through either a normal or a more expensive emergency resupply channel. When ordering a unit, each stocking location decides which channel to use based on its inventory level and the remaining leadtimes of the its outstanding orders. We consider the implications of this policy by developing expressions for the operating characteristics of the system...
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作者：Wang, MY; Sethi, SP; VandeVelde, SL
作者单位：University of Toronto; University of Texas System; University of Texas Dallas; Erasmus University Rotterdam; Erasmus University Rotterdam - Excl Erasmus MC
摘要：We study the problem of scheduling a chain-reentrant shop, in which each job goes for its processing first to a machine called the primary machine, then to a number of other machines in a fixed sequence, and finally back to the primary machine for its last operation. The problem is to schedule the jobs so as to minimize the makespan. This problem is unary NP-hard for a general number of machines. We focus in particular on the two-machine use that is also at least binary NP-hard. We prove some ...
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作者：Nurani, RK; Seshadri, S; Shanthikumar, JG
作者单位：Carnegie Mellon University; New York University; University of California System; University of California Berkeley
摘要：We consider a single stage production system with Poisson demand and exponential processing times. After producing a good item, the production process can shift to an ''out-of-control'' state with a given probability and start producing bad items. The state of the process is known only when the next stage (or customer) receives the item. Once an out-of-control process is detected, process correction is instantaneous. Customers arriving to an empty system get backlogged. In this framework, we e...
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作者：Stanford, DA
摘要：This paper presents new results for the interdeparture time distributions in single-server priority queues with an arbitrary number of high-priority Poisson-arrival classes and one lowest-priority general-arrival class. Little-known results for the waiting time distributions in the same queue are presented, including a new proof for the powerful result that the waiting time distribution in the non-preemptive priority queue is insensitive to the interarrival time distributions of lower-priority...
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作者：Flynn, J; Garstka, S
作者单位：Yale University
摘要：Consider a single-item, periodic review, infinite-horizon, undiscounted, inventory model with stochastic demands, proportional holding and shortage costs, and full backlogging. Orders can arrive in every period, and the cost of receiving them is negligible (as in a JIT setting). Every T periods, one observes the current stock level and orders deliveries for the next T periods, thus incurring a fixed setup cost. The goal is to find a review period T and an ordering policy that minimize the long...
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作者：Korhonen, P; Salo, S; Steuer, RE
作者单位：University System of Georgia; University of Georgia
摘要：In this paper we further investigate the problem of finding nadir criterion values (minimum criterion values over the nondominated set) in multiple objective linear programming. Although easy to obtain, the minimum values present in a payoff table are unreliable and should only be used with caution, especially in problems that have more than a small number of extreme points. To obtain better estimates of the nadir criterion values without adding great complexity to the task, we present an appr...
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作者：Pisinger, D
摘要：Several types of large-sized 0-1 Knapsack Problems (KP) may be easily solved, but in such cases most of the computational effort is used for sorting and reduction. In order to avoid this problem it has been proposed to solve the so-called core of the problem: a Knapsack Problem defined on a small subset of the variables. The exact core cannot, however, be identified before KP is solved to optimality, thus, previous algorithms had to rely on approximate core sizes. In this paper we present an a...
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作者：Martello, S; Toth, P
摘要：It is well-known that many instances of the 0-1 knapsack problem can be effectively solved to optimality also for very large values of n (the number of binary variables), while other instances cannot be solved for n equal to only a few hundreds. We propose upper bounds obtained from the mathematical model of the problem by adding valid inequalities on the cardinality of an optimal solution, and relaxing it in a Lagrangian fashion. We then introduce a specialized iterative technique for determi...
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作者：Hodgson, TJ; King, RE; Stanfield, PM
摘要：A frequently encountered scheduling problem is to determine simultaneously a material and job ready time and production sequence based on customer-specified due dates. Each job has a stochastic production time and a deterministic due date. The ready time is constrained in that the probability that each job will be complete by its due date must meet some minimum level of confidence. The objective in such an instance is to postpone the ready time as late as possible without violating these const...
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作者：Bevers, M; Hof, J; Uresk, DW; Schenbeck, GL
摘要：A discrete-time reaction-diffusion model for black-footed ferret release, population growth, and dispersal is combined with ferret carrying capacity constraints based on prairie dog population management decisions to form a spatial optimization model. Spatial arrangement of active prairie dog colonies within a ferret reintroduction area is optimized over time for maximum expected adult ferret population. This modeling approach is applied in an exploratory case study to a black-footed ferret re...
