Applied Mechanics and Materials Vols. 178-181

Abstract: In order to reduce the loss of multimodal transport logistics , ensure the efficient, safe, realize the emergency state unified command, information sharing, coordination, rapid rescue, the study established the multimodal transport logistics emergency decision-making function modules, researched and developed application system of emergency decision based on GIS+GPS, and VC# technologies.The system is easy to use, compatibility, strong practicability, it can provide technical support and application value for multimodal logistics emergency rescue.

Abstract: This study provided quantitative analyses about the influence of phasing sequences and the impact of intersection spacing. A large number of signal system scenarios were randomly generated to represent the real-world traffic systems. Based on simulation result, it was concluded that Leading and Lagging left turn phasing were more likely to be involved in progression bandwidth solution of signal systems with randomly distributed spacing. And the number of signals has significant impact on bandwidth attainability. Further conclusions were drawn from the fitting curve that it is impossible to obtain any two-way bandwidth solutions when more than 16 signals were involved in the system.

Abstract: In many-one distribution system, the Greedy Randomized Adaptive Search Procedure (GRASP) was applied to solve the Inventory-transportation Integrated Optimization problem (ITIO problem). The ITIO problem in many-one distribution system is difficult. When the product variety, the supplier quantity or the vehicle capacity increases, the calculated quantity will increase exponentially, and it is very difficult to get an exact solution. However, the GRASP can answer this problem. Further, by analyzing the computer experiments, it is proved that the GRASP can find the better solution to the ITIO problem in less time, and the quality of the solution will be improved with the size of the problem expanding.

Abstract: Water in pavement is a major contributor to pavement failure. Fine aggregates are pumped out near the joint of rigid pavement and cause the erosion of the base layer. In order to analyze the phenomenon, a two dimensional model using Finite Element Method (FEM) and Porous elasticity theory is developed to calculate the pore water pressure development in the base layer underneath joints. The model contains three parts, two cement concrete surface plates separated by a joint gap and a base layer with relatively small stiffness and large permeability. The constitutive behavior of porous medium material used in the model is introduced. Nodes along the depth direction of the base layer underneath the joint are analyzed to investigate the erosion of the base. Distributed loading is applied at the part area near the joint to simulate vehicle passing through the rigid pavement surface. Excess pore water pressure along the depth caused by external loading are calculated. The influence of vehicle speed on the base material is analyzed by adding a tire contacting with surface of the cement concrete. The results of the study show that vehicle speed does not only influence the magnitude but also the dissipation of the pore water pressure.

Abstract: Traffic Impact Analysis (TIA) is an effective approach to solve the urban traffic problems, by analyzing and assessing the impact of the new development to the peripheral traffic generation and the inherent relationship between land use and its current traffic condition. Based on the experience from foreign literature review, this paper first discusses the necessity of introduction TIA to China, and then compares the relationships between (1) TIA and city transportation planning (CTP) and (2) the basic methodology and standards of TIA. From a systematic perspective, this paper introduces the main content of TIA, and finally objective conclusions are drawn. This study indicates that TIA is the essential solution to prevent conflict between new development and new development interregional traffic generation. The findings of this paper would promote both the research of introduction TIA to China and furthermore the implementation of TIA.

Abstract: The operational safety and service quality of urban expressway are greatly affected by the distance of interchange opening. This paper definited the distance of 4 kinds of opening combination modes, showed the calculation models, and established a piecewise function model of opening distance, traffic volume and speed. It also proposed that, meeting the requirements of minimum distance, the opening distance should be determined with the consideration of actual road traffic conditions, by analyzing the relationship between the opening distance, traffic volume and speed. The results can be the references for the traffic management and the planning and designing of urban expressway interchange.

Abstract: With the development of society and economy, taxi service requirement is increasing, but the taxi traditional operation mode depending on chance has the obvious shortage, such as vehicle low efficiency, low customer service level, high empty driving rate, high fuel consumption, which already became an urgent problem to be solved for taxi management department. By the technology integration of the vehicle location, in-vehicle equipment, communication network and data platform, the Tele-taxi mode can realize the information linking and business coordination between the passengers and taxis.

Abstract: Based on GIS technology, location of logistic distribution center is realized. More factors, which effect the location of logistic distribution center, such as terrain, land use type, area etc., have been considered. Moreover, as an example, a case is given in the paper. In the case, the process of location of logistic distribution center has been realized based on ArcGIS. The results show that the location of logistic distribution center by using GIS technology is more intuitive and scientific than traditional method, and can provide the more scientific basis for relational work of logistic enterprise.

Abstract: We study the urban sub-traffic network, which amounts to 140 crossroads among the total ones in Beijing traffic organization. And an undirected, weighted network representation is adapted to the Beijing urban transportation network, where the vertices (nodes) correspond to the chosen crossroads and the weighted edges (links) to the travel speed among them. The complementary cumulative distribution and correlation of the topological structure are analyzed revealing that the network presents small-world property. The statistical properties of the network structure exhibit that there is linear, positive correlation between the strength of some node and the average strength of its neighbors. It is demonstrated that the weight-balance relations of the nodes conform to power-law distribution. Besides, for the communities (consisting definite number of nodes and the links completely connecting them), the average strength of the nodes is linearly proportional to the mean weight of the links.

Abstract: This paper analyzes the intrinsic relationship between the supply chain structure and its key factor, and builds a system dynamics model of supply chain under the advance payment financing business. Establishing the dynamic equations and simulating with Vensim simulation software, the result has been proved that prepayments financing has a positive impact on the supply chain performance.