| dc.description.abstract | This thesis addresses rich vehicle routing problems (VRPs) and introduces innovative algorithms for solving them. VRPs are vital in logistics, optimizing routes for the delivery of goods. Rich VRPs which incorporate real-world complexities, present significant computational challenges due to their intricate and often conflicting decision-making requirements. Efficient solution methods for these problems are essential in logistics, offering global companies critical decision support to minimize costs and emissions, maximize profits, and generate new business opportunities.
The presented research uses Operations Research (OR) methodologies and give industry decision support. The focal point of the thesis is the inventory routing problem (IRP), a hybrid problem consisting of routing and inventory management, where a vendor manages customer inventories, ensuring consistent stock levels while optimizing delivery schedules. Multiple solution approaches are developed for the IRP and the algorithms are also applied to other VRPs, confirming their effectiveness and versatility.
The thesis is divided into two segments: basic research and applied research. The basic research aims to advance the field of OR and strengthen future decision support systems. It comprises four papers, emphasizing route-based formulations. These papers contribute to the research literature by proposing efficient methodologies for creating and refining route sets, leading to enhanced solutions. This segment has yielded significant achievements, including 258 new best-known solutions for IRP benchmark instances, 560 for the production routing problem, 203 for the pickup and delivery problem with time windows, 28 for the multi-trip VRP, 20 for the VRP with time windows, and three for the capacitated VRP. These are all well-known benchmark problems.
The applied research targets the specific challenges of fish feed distribution in Norwegian aquaculture. Comprising two papers, this section showcases the applicability of optimization in the fish feed industry, underlining potential cost reductions through better routing and inventory management strategies.
In summary, this thesis not only propels the state of the art but also demonstrates the practical impact of these advancements in a real-world industry setting, thus bridging the gap between theoretical research and practical application. | en_US |
