%0 Journal Article
%T The Effects of the Tractor and Semitrailer Routing Problem on Mitigation of Carbon Dioxide Emissions
%A Hongqi Li
%A Yanran Li
%A Yue Lu
%A Qiang Song
%A Jun Zhang
%J Discrete Dynamics in Nature and Society
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/809135
%X The incorporation of emissions minimization in the vehicle routing problem (VRP) is of critical importance to enterprise practice. Focusing on the tractor and semitrailer routing problem with full truckloads between any two terminals of the network, this paper proposes a mathematical programming model with the objective of minimizing emissions per ton-kilometer. A simulated annealing (SA) algorithm is given to solve practical-scale problems. To evaluate the performance of the proposed algorithm, a lower bound is developed. Computational experiments on various problems generated randomly and a realistic instance are conducted. The results show that the proposed methods are effective and the algorithm can provide reasonable solutions within an acceptable computational time. 1. Introduction and Problem Description Along with the growth of the demand for goods, transportation volume is increasing rapidly. For door-to-door transportation, the most widely used mode is road transportation. However, road transportation has some negative impact on the environment because of the land use, energy resource consumption, and so forth. Road transportation accounts for almost 80% of total energy demands from transportation [1]. Fossil fuels are the main energy sources of transportation and is emitted during the combustion of fossil fuels. As a dominant mode of freight movement, road transportation accounts for the largest share of the freight-related emissions [2]. The percentages of road freight transportation emissions compared to the entire transportation sector from 1985 to 2007 in China were between 29% and 34% [3]. More and more tons of are released into the environment annually and the road freight transportation emissions are likely to keep growth. Recent studies on freight transportation have focused not only on cost minimization or profit maximization for a freight company but also on carbon reduction to enhance the corporate social responsibility for the company [4]. The fuel consumption is the most expensive variable cost of the transportation process to road freight transportation enterprises [5]. The efficient use of trucks and road networks becomes more and more important. Compared with costly network infrastructure modifications, optimized routing strategies have been proven to be more efficient in enhancing network capacity [6]. Optimized vehicle routing can reduce the number of trucks and utilize the network better by reducing vehicle movements. The optimization problem has been extensively studied in the literature, known as the vehicle routing
%U http://www.hindawi.com/journals/ddns/2013/809135/