TY - JOUR
T1 - The Lagrangian Relaxation Method for the Shortest Path Problem Considering Transportation Plans and Budgetary Constraint
TT - روش دوگان لاگرانژی برای مسأله کوتاهترین مسیر با درنظرگرفتن طرحهای عمرانی همراه با محدودیت بودجه
JF - JAMLU
JO - JAMLU
VL - 16
IS - 2
UR - http://jamlu.liau.ac.ir/article-1-1631-en.html
Y1 - 2019
SP - 39
EP - 57
KW - Transportation Network
KW - Constrained Shortest Path Problem
KW - Lagrangian Dual Method
KW - Sub-gradient Method.
N2 - In this paper, a constrained shortest path problem (CSP) in a network is investigated, in which some special plans for each link with corresponding pre-determined costs as well as reduction values in the link travel time are considered. The purpose is to find a path and selecting the best plans on its links, to improve the travel time as most as possible, while the costs of conducting plans do not exceed the available budget. Using the Lagrangian relaxation approach, some constraints of the problem are relaxed and the Lagrangian dual problem is decomposed into two smaller sub-problems. Then, by applying the sub-gradient algorithm, a near optimal solution is determined for the original problem. Finally, by considering the proposed model on a small-sized network and on Khorasan state network, solutions for different origin-destination pairs with different parameters are determined.
M3
ER -