Paper Info
Title
Flexible servers in tandem lines with setup costs
Abstract
We study the dynamic assignment of flexible servers to stations in the presence of setup costs that are incurred when servers move between stations. The goal is to maximize the long-run average profit. We provide a general problem formulation and some structural results, and then concentrate on tandem lines with two stations, two servers, and a finite buffer between the stations. We investigate how the optimal server assignment policy for such systems depends on the magnitude of the setup costs, as well as on the homogeneity of servers and tasks. More specifically, for systems with either homogeneous servers or homogeneous tasks, small buffer sizes, and constant setup cost, we prove the optimality of "multiple threshold" policies (where servers' movement between stations depends on both the number of jobs in the system and the locations of the servers) and determine the values of the thresholds. For systems with heterogeneous servers and tasks, small buffers, and constant setup cost, we provide results that partially characterize the optimal server assignment policy. Finally, for systems with larger buffer sizes and various service rate and setup cost configurations, we present structural results for the optimal policy and provide numerical results that strongly support the optimality of multiple threshold policies.
Year
DOI
Venue
2012
10.1007/s11134-011-9263-9
Queueing Syst.
Keywords
Field
DocType
Flexible servers,Finite buffers,Markov decision processes,Setup costs,Tandem production systems,Threshold policies,90B22,90C40,60J28
Tandem,Mathematical optimization,Homogeneity (statistics),Homogeneous,Computer science,Server,Markov decision process,Real-time computing
Journal
Volume
Issue
ISSN
70
2
0257-0130
Citations 
PageRank 
References 
3
0.41
15
Authors
3
Name
Order
Citations
PageRank
Sigrún Andradóttir154855.09
Hayriye Ayhan221726.52
Eser Kırkızlar330.75