2,872 research outputs found
Solution Approaches for Vehicle and Crew Scheduling with Electric Buses
The use of electric buses is expected to rise due to its environmental benefits. However, electric vehicles are less exible than conventional diesel buses due to their limited driving range and longer recharging times. Therefore, scheduling electric vehicles adds further operational dificulties. Additionally, various labor regulations challenge public transport companies to find a cost-effcient crew schedule. Vehicle and crew scheduling problems essentially define the cost of operations. In practice, these two problems are often solved sequentially. In this paper, we introduce the integrated electric vehicle and crew scheduling problem (E-VCSP). Given a set of timetabled trips and recharging stations, the E-VCSP is concerned with finding vehicle and crew schedules that cover the timetabled trips and satisfy operational constraints, such as limited driving range of electric vehicles and labor regulations for the crew while minimizing total operational cost. An adaptive large neighborhood search that utilizes branch-and-price heuristics is proposed to tackle the E-VCSP. The proposed method is tested on real-life instances from public transport companies in Denmark and Sweden that contain up to 1,109 timetabled trips. The heuristic approach provides evidence of improving efficiency of transport systems when the electric vehicle and crew scheduling aspects are considered simultaneously. By comparing to the traditional sequential approach, the heuristic finds improvements in the range of 1.17-4.37% on average. A sensitivity analysis of the electric bus technology is carried out to indicate its implications for the crew schedule and the total operational cost. The analysis shows that the operational cost decreases with increasing driving range (120 to 250 kilometers) of electric vehicles
On green routing and scheduling problem
The vehicle routing and scheduling problem has been studied with much
interest within the last four decades. In this paper, some of the existing
literature dealing with routing and scheduling problems with environmental
issues is reviewed, and a description is provided of the problems that have
been investigated and how they are treated using combinatorial optimization
tools
Internet of Things in urban waste collection
Nowadays, the waste collection management has an important role in urban areas. This paper faces this issue and proposes the application of a metaheuristic for the optimization of a weekly schedule and routing of the waste collection activities in an urban area. Differently to several contributions in literature, fixed periodic routes are not imposed. The results significantly improve the performance of the company involved, both in terms of resources used and costs saving
A ride time-oriented scheduling algorithm for dial-a-ride problems
This paper offers a new algorithm to efficiently optimize scheduling
decisions for dial-a-ride problems (DARPs), including problem variants
considering electric and autonomous vehicles (e-ADARPs). The scheduling
heuristic, based on linear programming theory, aims at finding minimal user
ride time schedules in polynomial time. The algorithm can either return optimal
feasible routes or it can return incorrect infeasibility declarations, on which
feasibility can be recovered through a specifically-designed heuristic. The
algorithm is furthermore supplemented by a battery management algorithm that
can be used to determine charging decisions for electric and autonomous vehicle
fleets. Timing solutions from the proposed scheduling algorithm are obtained on
millions of routes extracted from DARP and e-ADARP benchmark instances. They
are compared to those obtained from a linear program, as well as to popular
scheduling procedures from the DARP literature. Results show that the proposed
procedure outperforms state-of-the-art scheduling algorithms, both in terms of
compute-efficiency and solution quality.Comment: 12 pages, 1 figur
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