Dynamic dispatching and repositioning policies for fast-response service networks

Abstract We address the problem of dispatching and pro-actively repositioning service resources in service networks such that fast responses to service requests are realized in a cost-efficient way. By formulating this problem as a Markov decision process, we are able to investigate the structure of the optimal policy in the application domain of service logistics. Using these insights, we then propose scalable dynamic heuristics for both the dispatching and repositioning sub-problem, based on the minimum weighted bipartite matching problem and the maximum expected covering location problem, respectively. The dynamic dispatching heuristic takes into account real-time information about both the state of equipment and the fleet of service engineers, while the dynamic repositioning heuristic maximizes the expected weighted coverage of future service requests. In a test bed with a small network, we show that our most advanced heuristic performs well with an average optimality gap of 4.3% for symmetric instances and 5.8% for asymmetric instances. To show the practical value of our proposed heuristics, extensive numerical experiments are conducted on a large test bed with service logistics networks of real-life size where significant savings of up to 56% compared to a state-of-the-art benchmark policy are attained.

[1]  Michael N. Katehakis,et al.  Optimal Repair Allocation in a Series System , 1984, Math. Oper. Res..

[2]  Steve Y. Chiu,et al.  Effective Heuristic Procedures for a Field Technician Scheduling Problem , 2001, J. Heuristics.

[3]  Michael N. Katehakis,et al.  Optimal repair allocation in a series system expected discounted operation time criterion , 1987 .

[4]  Susan R. Hunter,et al.  A Bound on the Performance of an Optimal Ambulance Redeployment Policy , 2014, Oper. Res..

[5]  S. Bhulai,et al.  A dynamic ambulance management model for rural areas , 2017, Health care management science.

[6]  Matthew S. Maxwell,et al.  Approximate Dynamic Programming for Ambulance Redeployment , 2010, INFORMS J. Comput..

[7]  Peter Kolesar,et al.  The Feasibility of One-Officer Patrol in New York City , 1984 .

[8]  Fatih Camci,et al.  European Journal of Operational Research Maintenance Scheduling of Geographically Distributed Assets with Prognostics Information , 2022 .

[9]  Sandjai Bhulai,et al.  The effect of ambulance relocations on the performance of ambulance service providers , 2016, Eur. J. Oper. Res..

[10]  Bram de Jonge,et al.  Condition-based maintenance in the cyclic patrolling repairman problem , 2020 .

[11]  Verena Schmid,et al.  Solving the dynamic ambulance relocation and dispatching problem using approximate dynamic programming , 2012, Eur. J. Oper. Res..

[12]  Armann Ingolfsson,et al.  A Markov Chain Model for an EMS System with Repositioning , 2013 .

[13]  N. C. Simpson,et al.  Fifty years of operational research and emergency response , 2009, J. Oper. Res. Soc..

[14]  Arthur J. Swersey A Markovian Decision Model for Deciding How Many Fire Companies to Dispatch , 1982 .

[15]  Chandra Ade Irawan,et al.  Optimisation of maintenance routing and scheduling for offshore wind farms , 2017, Eur. J. Oper. Res..

[16]  Richard F. Hartl,et al.  Adaptive large neighborhood search for service technician routing and scheduling problems , 2012, J. Sched..

[17]  Jan M. Chaiken,et al.  Response Areas for Two Emergency Units , 1972, Oper. Res..

[18]  Benoît Iung,et al.  Dynamic maintenance grouping and routing for geographically dispersed production systems , 2019, Reliab. Eng. Syst. Saf..

[19]  W. H. M. Zijm,et al.  Warehouse design and control: Framework and literature review , 2000, Eur. J. Oper. Res..

[20]  Frank Meisel,et al.  Workforce routing and scheduling for electricity network maintenance with downtime minimization , 2013, Eur. J. Oper. Res..

[21]  Pierre Dejax,et al.  Exact and hybrid methods for the multiperiod field service routing problem , 2013, Central Eur. J. Oper. Res..

[22]  Sandjai Bhulai,et al.  An efficient heuristic for real-time ambulance redeployment , 2015 .

[23]  David Simchi-Levi,et al.  Two-echelon spare parts inventory system subject to a service constraint , 2004 .

[24]  C. J. Jagtenberg,et al.  Dynamic ambulance dispatching: is the closest-idle policy always optimal? , 2017, Health care management science.

[25]  Kees Jan Roodbergen,et al.  Coordinating technician allocation and maintenance routing for offshore wind farms , 2018, Comput. Oper. Res..

[26]  Linda V. Green,et al.  A Multiple Dispatch Queueing Model of Police Patrol Operations , 1984 .

[27]  Christelle Guéret,et al.  A parallel matheuristic for the technician routing and scheduling problem , 2013, Optim. Lett..

[28]  Bob Huisman,et al.  Maintenance spare parts planning and control: a framework for control and agenda for future research , 2014 .

[29]  Stephen C. Graves,et al.  A Multi-Echelon Inventory Model for a Repairable Item with One-for-One Replenishment , 1985 .

[30]  A. Benmerzouga,et al.  Optimal (m-FailureP-Repairmen) policies with random repair time , 1999 .

[31]  Samir Elhedhli,et al.  A stochastic optimization model for real-time ambulance redeployment , 2013, Comput. Oper. Res..

[32]  Edward Ignall,et al.  An Algorithm for the Initial Dispatch of Fire Companies , 1982 .

[33]  Mark S. Daskin,et al.  A Maximum Expected Covering Location Model: Formulation, Properties and Heuristic Solution , 1983 .

[34]  Nacima Labadie,et al.  On the combined maintenance and routing optimization problem , 2016, Reliab. Eng. Syst. Saf..

[35]  Ramayya Krishnan,et al.  An Efficient Simulation-Based Approach to Ambulance Fleet Allocation and Dynamic Redeployment , 2012, AAAI.

[36]  R. Bellman A Markovian Decision Process , 1957 .

[37]  Fernando Ordóñez,et al.  A robust optimization approach to dispatching technicians under stochastic service times , 2013, Optim. Lett..

[38]  Angel B. Ruiz,et al.  Recent optimization models and trends in location, relocation, and dispatching of emergency medical vehicles , 2019, Eur. J. Oper. Res..