Ankara : The Department of Industrial Engineering and the Institute of Engineering and Science of Bilkent University, 2009.Thesis (Master's) -- Bilkent University, 2009.Includes bibliographical references leaves 45-46.In this study, we aim to design a distribution system with the following components:
the location of vendors, the number of vendors, the service region of
the vendors, the number of vehicles and workers, and the assignment of demand
points to these vendors and vehicles. We define our problem as a two-level capacitated
discrete facility location problem with minimum profit constraints and
call it Vendor Location Problem. In order to formulate the problem, two different
objective functions are used: vendors’s profit maximization and maximization of
the demand covered. Integer linear programs for these two versions of the problem
are formulated. Valid inequalities are used to strengthen the upper bounds.
Finally, the performance of these models with different parameters are compared
in terms of linear programming relaxation gap, optimality gap, CPU time, and
the number of opened nodes for four different types of instances: instances with
demand and profit which are independent of distance; profit function of distance;
demand function of distance; demand and profit function of distance.Çınar, YüceM.S