چكيده به لاتين
Locating on the railway is a fundamental issue in the field of rail transport that has a direct impact on the efficiency and quality of services provided. This thesis examines an important issue, namely locating inspection posts in the design of the railway network. The aim of this research is to find the optimal locations for creating inspection posts on the railway network in such a way that the two main goals of reducing costs and increasing safety are met simultaneously. These two goals are inversely related to each other, in other words, as the number of inspection posts increases, productivity decreases and, as a result, travel costs increase, but travel safety will increase due to the increase in inspections and the discovery of more failures. On the other hand, as the number of inspection posts decreases, productivity and travel speed of wagons increase and travel costs decrease, but travel safety is reduced. By determining a balance between these two goals, it will be possible to find the optimal location for inspection posts on the railway network. In this study, a dual-objective mathematical model has been written with the objectives of reducing costs, including the costs of stopping the train, the costs of sending damaged wagons from inspection posts to the depot, and the costs of creating an inspection post, increasing the safety of movement, and discovering as many defects as possible. Then, to evaluate its effectiveness, the model has been implemented in the GAMS software and solved using a small numerical example and a case study of the railway network of the Islamic Republic of Iran. Since this problem is written as a dual-objective problem, it does not have a unique optimal solution, but Pareto optimal solutions have been generated for this problem. In the resulting Pareto solution set, the number of inspection posts can be a number between 53 and 80, and the decision maker can choose the appropriate solution from this solution set,considering his preferences and priorities.
