en و موضوعات مربوط Other Related Subject پژوهشي Research <span style="FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 11pt mso-ansi-language: EN-US mso-fareast-font-family: 'Times New Roman' mso-fareast-language: EN-US mso-bidi-language: FA"><em>The Network Design Problem (NDP) is one of the important problems in combinatorial optimization. Among the network design problems, the Multicommodity Capacitated Network Design (MCND) problem has numerous applications in transportation, logistics, telecommunication, and production systems. The MCND problems with splittable flow variables are NP-hard, which means they require exponential time to be solved in optimality. With binary flow variables or unsplittable MCND, the complexity of the problem is increased significantly. With growing complexity and scale of real world capacitated network design applications, metaheuristics must be developed to solve these problems. This paper presents a simulated annealing approach with innovative representation and neighborhood structure for unsplittable MCND problem. The parameters of the proposed algorithms are tuned using Design of Experiments (DOE) method and the Design-Expert statistical software. The performance of the proposed algorithm is evaluated by solving instances with different dimensions from OR-Library. The results of the proposed algorithm are compared with the solutions of CPLEX solver.<font face="Times New Roman"><span style="mso-spacerun: yes"><font size="3">  </font></span>The results show that the proposed SA can find near optimal solution in much less time than exact algorithm.</font></em></span> Network Design Problem,Unsplittable Multicommodity Capacitated Network Design Problem, Metaheuristic, Simulated Annealing 91 100 http://ijiepr.iust.ac.ir/browse.php?a_code=A-10-94-10&slc_lang=en&sid=1 Masoud Yaghini yaghini@iust.ac.ir 180031947532846001771 180031947532846001771 Yes School of Railway Engineering, Iran University of Science and Technology Mohammad Rahim Akhavan 180031947532846001772 180031947532846001772 No Department of Railway Transportation Engineering, Kermanshah University of Science and Technology