Chongqing University of Technology

About: Chongqing University of Technology is a education organization based out in Chongqing, China. It is known for research contribution in the topics: Microstructure & Alloy. The organization has 5199 authors who have published 4205 publications receiving 35954 citations. The organization is also known as: Chongqing Institute of Technology.

Last Mile Delivery With Stochastic Travel Times Considering Dual Services

Abstract: Nowadays there are two prevailing delivery modes in the last mile delivery; one is the home delivery (HD) that vehicles deliver parcels to customers' homes; and the other is the customers' pickup (CP) that vehicle deliver parcels to some kind of intelligent express boxes where customers can pick up their parcels with free time. This article studies a green vehicle routing problem considering dual services (HD and CP) with stochastic travel times (GVRP-DS-STT) to provide customers with sustainable and diversified delivery services. The GVRP-DS-STT problem is formulated as a two-stage stochastic optimization model with recourse strategy. The purpose of the model is to minimize the total operational cost under stochastic environment. In addition, a two-stage heuristic algorithm integrating with a sampling strategy is developed to solve approximately the problem, the first of which is the greedy-based initial feasible solution generation, and the second of which is an improvement heuristic with late acceptance to explore the solution space. The computational results show that there are increasing benefit in terms of total operational cost, number of the vehicles used and loading rate with the increase of percentage of CP customers. The time windows have great effect on the operational cost, but more CP customers can reduce their impact. The stochastic model outperforms the deterministic model in terms of total operational cost.

Regional difference and driving factors of industrial carbon emissions performance in China

Abstract: Industry is the pillar of China’s national economy. The energy-saving and emission reduction in the industrial sector directly bear on the sustainable development of the whole country. This paper sets up an evaluation index system for industrial carbon emissions performance (ICEP), and then evaluates the ICEPs in 30 Chinese provinces from 2003 to 2017, using the stochastic block model (SBM). Based on the regional difference of the ICEP, a Tobit model was established to identify the driving factors of the ICEP. The main results are as follows: (1) There are obvious provincial differences in the ICEP: coastal provinces (e.g. Zhejiang, Shanghai, Beijing, Jiangsu, and Guangdong) had relatively high ICEPs, while inland provinces (e.g. Yunnan, Guizhou, Ningxia, Shanxi and Qinghai) had undesirable ICEPs. (2) The three regions of China can be ranked as eastern region, central region, and western region in descending order of the ICEP. The central and western regions should be focused to promote energy-saving and emission reduction in the industrial sector. (3) The ICEP clustering shows that the ICEPs were medium and low in most provinces, and high in very few provinces. (4) Regression results of the Tobit model demonstrate that different driving factors have varied effects on the ICEP: economic development, technical progress, and foreign trade have significant positive effects on the ICEP, while energy structure and environmental regulation have significant negative effects on the ICEP.