Publication Type
Journal Article
Version
submittedVersion
Publication Date
6-2020
Abstract
Many manufacturing and service systems require a finite number of heterogeneous jobs to be processed by two stations in tandem. Each station serves at most one job at a time and there is a finite buffer between the two stations. We consider two flexible servers that are cross-trained to work at both stations. The duration for a server to finish a job at a station is exponentially distributed with a rate that depends on the server, the station, and the job. Our goal is to identify an efficient policy to dynamically assign the servers to the stations such that the expected makespan (duration to complete all the jobs) is minimized. Given that an optimal policy is non-idling, we focus on non-idling policies. We first derive the expected makespan of a general non-idling policy. We then analyze three simple non-idling policies: the summation-myopic, the product-myopic, and the teamwork policies. We prove that (i) the product-myopic policy is optimal if the servers maintain the same service-rate ratio at each station for all the jobs, (ii) the teamwork policy is optimal if the servers maintain the same service-rate ratio at different stations for jobs that are sequenced near each other, and (iii) the summation-myopic policy is no worse than the teamwork policy. Our numerical study based on general service rates suggests that the summation-myopic policy can be better or worse than the product-myopic policy. We also extend the model to incorporate moving costs and service defects.
Keywords
Manufacturing, Service, Work station, Dynamic server assignment, Productivity
Discipline
Operations and Supply Chain Management | Operations Research, Systems Engineering and Industrial Engineering
Research Areas
Operations Management
Publication
Production and Operations Management
Volume
29
Issue
6
First Page
1431
Last Page
1447
ISSN
1059-1478
Identifier
10.1111/poms.13172
Publisher
Wiley: 24 months
Citation
LIM, Yun Fong; LU, Bingnan; WANG, Rowan; and ZHANG, Wenjia.
Flexibly serving a finite number of heterogeneous jobs in a tandem system. (2020). Production and Operations Management. 29, (6), 1431-1447.
Available at: https://ink.library.smu.edu.sg/lkcsb_research/6547
Copyright Owner and License
Authors
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
External URL
http://www.mysmu.edu/faculty/yflim/
Additional URL
https://doi.org/10.1111/poms.13172
Included in
Operations and Supply Chain Management Commons, Operations Research, Systems Engineering and Industrial Engineering Commons