An index policy for routing agricultural machinery repairs

• 成果类型: Article; Early Access
• 署名作者: Yao, Yipu; Ding, Li; Zhao, Yanlu
• 署名单位: Durham University; Renmin University of China
• 刊物名称: PRODUCTION AND OPERATIONS MANAGEMENT
• ISSN/ISSBN: 1059-1478
• DOI: 10.1177/10591478261476256
• 发表日期: 2026
• 关键词: restless bandits; server queues; MODEL; COSTS; maintenance; heuristics; admission; parallel; DESIGN; SYSTEM

摘要

We study dynamic routing in an agricultural machinery repair network where mobile repair teams travel to spatially dispersed breakdowns and both travel and on-site repair times are stochastic and comparable. We formulate a finite-horizon Markov decision process tracking each team's job list and service path, and derive a tractable index-based policy via Whittle-style Lagrangian relaxation that decomposes the original problem into team-wise subproblems. For each team, we obtain a closed-form index, prove indexability, and show that indices preserve their cross-team ordering under finite horizons, ensuring consistent decision rules without additional computation. On the analytical side, the Lagrangian dual yields a computable lower bound against which the index policy is asymptotically optimal. A case study and extensive experiments demonstrate that the index policy achieves the lowest average cost in most tested instances, with an average optimality gap of 1.72% and up to 67% cost reduction over heuristic benchmarks. Sensitivity analysis further confirm robustness under varying system loads, service imbalance, spatial distributions, and other extensions.