Date of Graduation
8-2018
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Engineering (PhD)
Degree Level
Graduate
Department
Industrial Engineering
Advisor/Mentor
Sullivan, Kelly M.
Committee Member
Pohl, Edward A.
Second Committee Member
Nurre, Sarah
Third Committee Member
Smith, J. Cole
Keywords
Interdependent Networks; Network Optimization; Yard Routing
Abstract
In this dissertation, we model three network-based optimization problems. Chapter 2 addresses the question of what the operation plan should be for interdependent infrastructure systems in resource-constrained environments so that they collectively operate at the highest level. We develop a network-based operation model of these systems that accounts for interdependencies among them. To solve this large-scale model, a solution approach is proposed that relatively quickly generates high-quality solutions to the problem.
Chapter 3 presents a routing model for a single train within a railyard with the objective of minimizing the total length traveled by train. The difference between this problem and the traditional shortest path is that the route must accommodate the length of the train at any time, subject to yard tracks’ configuration. This problem has application in the railway industry where they need to solve the single-train routing problem repeatedly for simulations of train movements in large complex yards. We develop an optimal polynomial-time algorithm that solves an important special case of the problem.
Chapter 4 extends the problem defined in Chapter 3 to a two-train routing problem with the objective of minimizing the overall time possible to schedule the routes in a conflict-free manner. We propose a routing problem that indirectly aims to decrease the overall scheduling time for the two trains. We develop a scheduling model that compares the performance of the solution obtained by the proposed routing model with the solutions obtained by solving the problem as two separate single-train yard routing problems. The comparison indicates a better performance obtained by the proposed routing model for specific problems.
Citation
Enayaty Ahangar, N. (2018). Modeling and Solution Approaches for Non-traditional Network Flow Problems with Complicating Constraints. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/2895
Included in
Industrial Engineering Commons, Industrial Technology Commons, Operational Research Commons