Browsing by Author "King, Jacobus Coenraad Petrus"
Now showing 1 - 1 of 1
Results Per Page
Sort Options
- ItemA new vehicle routing problem for increased driver-route familiarity(Stellenbosch : Stellenbosch University, 2023-12) King, Jacobus Coenraad Petrus; van Vuuren, J. H.; Toth, P.; Stellenbosch University. Faculty of Engineering. Dept. of Industrial Engineering. Engineering Management (MEM).ENGLISH ABSTRACT: Practical challenges often arise when implementing solutions that stem from solving vehicle routing problem instances. Unplanned external events can result in increased vehicle travel times and subsequent degradations in supply chain operational efficiency. Moreover, drivers tend to get lost and/or often travel on roads that are not suitable for their delivery vehicles when they are unfamiliar with delivery routes, especially when these routes differ significantly from one day to the next. A possible solution, aimed at streamlining the practical implementation of planned delivery routes, is therefore to attempt to increase driver-route familiarity. A novel framework, called the familiarity vehicle routing problem (FVRP) framework, is proposed in this dissertation for improving the practical implementation of planned delivery routes by introducing increased driver-route familiarity into vehicle delivery routes. The FVRP framework consists of two phases — a strategic phase and an operational phase. During the strategic phase, a set of standard delivery routes visiting each customer along a specified number of different approaches is generated for a depot and the customers it services. These routes are called master routes and are then used as blueprints for daily planning purposes when actual delivery routes are computed during the subsequent operational phase. Delivery vehicle drivers are thus afforded the opportunity to become familiar with the master routes, which is anticipated to increase the efficiency with which they will be able to perform deliveries in the long term (if their actual delivery routes do not deviate too much from these master routes). Two novel mathematical models and accompanying approximate solution approaches are proposed for the different phases of the FVRP. The (single-objective) mathematical model for the strategic phase is concerned with generating a minimum-cost set of master routes for a given depot and the customers it services. The set of arcs that form these master routes represent road links with which delivery vehicle drivers may become increasingly familiar as they continue to travel along them during future deliveries. The set of master route arcs are provided as input to the (bi-objective) mathematical model proposed for the operational phase of the FVRP. This model is concerned with computing multiple trade-off solutions which can serve as actual delivery routes along which the objectives are to minimise transportation cost and to maximise the portion of the total distance travelled along the master route arcs. Furthermore, a novel recycling heuristic is proposed which facilitates the use of historical solutions when generating initial solutions for the approximate solution approach of the operational phase. The framework and computerised implementations of its components are finally applied to a special case study, involving real-world data, in order to demonstrate the practical applicability of the work reported in this dissertation.