مسیریابی وسیله نقلیه با منابع قابل حمل
Abstract
1. Introduction
2. Literature review
3. Problem formulation
4. Methodology
5. Computational experiments
6. Managerial insights
7. Conclusion, perspectives, and future works
Acknowledgment
Appendix A. Supplementary materials
Research Data
References
Abstract
In the classical Vehicle Routing Problem (VRP), it is assumed that each worker moves using an individually assigned vehicle. Removing this core hypothesis opens the door for a brand new set of solutions, where workers are seen as transportable resources that can also move without the help of a vehicle. In this context, motivated by a major European energy provider, we consider a situation where workers can either walk or drive to reach a job and where carpooling is enabled. In order to quantify the potential benefits offered by this new framework, a dedicated Variable Neighborhood Search is proposed to efficiently tackle the underlying synchronization and precedence constraints that arise in this extension of the VRP. Considering a set of instances in an urban context, extensive computational experiments show that, despite conservative scenarios favoring car mobility, significant savings are achieved when compared to the solutions currently obtained by the involved company. This innovative formulation allows managers to reduce the size of the vehicle fleet while keeping the number of workers stable and, surprisingly, decreasing the overall driving distance simultaneously.
Introduction
Transportation in urban areas is increasingly facing new challenges. On the one hand, the systematic use of cars produces hazardous impacts on the environment, such as noise, toxic emissions, and the effects induced by greenhouse gases (Knörr, 2008). On the other hand, as highlighted by Jabali, Woensel, and de Kok (2012), city centers suffer from congestion and limited parking space. These phenomena, which are magnified by low vehicle occupancy rates, decrease the intrinsic efficiency of car-based transportation. Consequently, current legislation tends to constrain the use of cars within city centers either by limiting the number of authorized vehicles or completely banning vehicles in specific areas, such as pedestrian zones, as highlighted by Parragh and Cordeau (2017). For all these reasons, reducing the systematic use of cars in urban areas is becoming increasingly important. Firms that provide on-site services or parcel deliveries are directly concerned by these issues, as a substantial part of their activities takes place in metropolitan areas. We focus on the case of a large European energy provider, denoted by EEP (it cannot be named because of a non-disclosure agreement), that routes technicians to provide on-site services (e.g., small maintenance work, consumption evaluations, and consumer-setting upgrades). Every day, technicians who are not assigned to clients are employed for heavy works on the electricity network. However, once assigned to on-site services, the workers cannot be re-assigned thereafter to heavy works, even if they terminate their working day earlier.