Hybrid Heuristic for Vehicle Routing Problem with Time Windows and Compatibility Constraints in Home Healthcare System

Abstract

This work involves a heuristic for solving vehicle routing problems with time windows (VRPTW) with general compatibility-matching between customer/patient and server/caretaker constraints to capture the nature of systems such as caretakers’ home visiting systems or home healthcare (HHC) systems. Since any variation of VRPTW is more complicated than regular VRP, a specific, custom-made heuristic is needed to solve the problem. The heuristic proposed in this work is an efficient hybrid of a novice Local Search (LS), Ruin and Recreate procedure (R&R) and Particle Swarm Optimization (PSO). The proposed LS acts as the initial solution finder as well as the engine for finding a feasible/local optimum. While PSO helps in moving from current best solution to the next best solution, the R&R part allows the solution to be over-optimized and LS moves the solution back on the feasible side. To test our heuristic, we solved 56 benchmark instances of 25, 50, and 100 customers and found that our heuristics can find 52, 21, and 18 optimal cases, respectively. To further investigate the proficiency of our heuristic, we modified the benchmark instances to include compatibility constraints. The results show that our heuristic can reach the optimal solutions in 5 out of 56 instances.

Consideration of Carbon Emissions in Multi-Trip Delivery Optimization of Unmanned Vehicles

“…The unmanned vehicle delivery routing problem is fundamentally a VRP, which has found a growing range of applications that require its solving in daily life, such as material distributions [9], drone path optimization [10,11], home healthcare system applications [12], public transit services' mode and route optimization [13], electric vehicle path problems considering battery charging status [14][15][16], dynamic VRPs [17,18], emergency material dispatch optimization [19][20][21], service-oriented collaborative VRPs [22], and green delivery path problems [23,24]. In contrast to the traditional vehicle routing problem (VRP), the incorporation of unmanned vehicles facilitates continuous 24 h back-and-forth deliveries without the requirement of human drivers.…”

“…Equation (11) ensures that the number of vehicles departing from the distribution center does not exceed the total number of available vehicles. Equation (12) dictates that the number of entries and exits of unmanned vehicles from the distribution center during any trip should be equal. Equation ( 13) addresses the load capacity of unmanned vehicles for individual trips, while Equation ( 14) imposes constraints on the overall load capacity of unmanned vehicles.…”

Transportation and Reserve of Emergency Medical Supplies during Public Health Events

“…This heuristic algorithm is an efficient hybrid of a novice local search (LS), ruin and recreate procedure (R&R) and particle swarm optimization (PSO). This heuristic algorithm can solve this VRPTW problem efficiently [22]. Díaz de León-Hicks, E., and other scholars investigated the use of method selection that can solve the VRPTW problem.…”