Advanced Materials Research Vols. 1030-1032

Abstract: Considered the influence of buses on cars’ change lanes and lane-changing of buses, this paper built an asymmetric cellular automata lane changing model under mixed traffic flow based on symmetric two-lane cellular automata lane-changing model and studied driveway occupancy and road characteristics with related parameters. Computer simulation showed that bus ratio has significant impact on lane-changing probability of vehicles.

Abstract: Vehicle routing problem with time Windows (VRPTW) that is a kind of important extension type for VPR. In view of problem which the ant colony algorithm in solving VRPTW easily plunged into local optimum , this paper defines a new ant transition probability of saving ideas, and uses the Pareto optimal solution set of global pheromone updating rule, and puts forward a kind of improved Pareto ant colony algorithm (IPACA) . Through the simulation experiments show that IPACA improves the global search ability of ACA, effectively avoids the algorithm falls into local optimum, and reduces the total distribution cost (distance), so as to verify the effectiveness of the proposed algorithm.

Abstract: Based on the traffic network design problem of traditional deterministic travel demand, the traffic emission in road network, especially the traffic emission at intersection is studied, and a bi-level programming model for traffic pollution control based on continuous traffic network countermeasure is developed. The object of the upper level is to minimize the sum of the total impedance in network system and the total investment cost, and constraint conditions are set as the road traffic emissions and intersection traffic emissions. The lower level is a user equilibrium model. A numerical example is given to prove the rationality of the model at last.

Abstract: Assist characteristics design is one of the key technologies of ECHPS system.For the problem of poor steering safety in high speed caused by HPS with fixed assist characteristics in heavy commercial vehicle, design requirement of alterable assist characteristics is analyzed, and simulation models of ECHPS system, including mechanical model ,hydraulic model and three degrees freedom vehicle dynamic model are established by taking the bypass flow ECHPS of heavy commercial vehicle as the research object. Assist characteristics of ECHPS under different speeds are achieved by simulation models.Simulation results show that, ECHPS system can not only improve the steering easiness at low speed but also keep good road feel and handling stability at high speed.

Abstract: Curve adjusting is an important part in the railway maintenance and plays a major role in the railway safe operations. To meet the requirements of calculating versine in the lining and lifting work carried out by the tamping wagon, this paper proposes an approach for modelling the track curve and an algorithm for calculating the versine of any point in the rectangular coordinate system. The model and the algorithm are both verified and proved.

Abstract: In logistics activities, the choice of the transportation mode involves time, price, safety, and many other factors, it is a typical multi-attribute decision making problem. Traditionally, we usually adopt a certain decision-making method to solve such problems, but the resulting solution is often difficult to achieve our desired results. This article tries to combine AHP, information entropy method and the TOPSIS method to solve the multiple-attribute decision making problems in the process of transportation activity, and finally a case is given.

Abstract: Taking a new subway going through under the existing subway station as the engineering background, based on geological exploration data in the field, the deformation influence for the station structure of the existing subway when the main structure station constructs could be studied. It constructed a three dimensional calculation model by Ansys software to simulate the transverse and vertical deformation and the stress variation of new building line station's main structure, Through the analysis of the results,it put forward the predictive analysis to control the risk. To ensure the safety in construction process through adjust the construction scheme timely. It provided the corresponding reference for the such subway building project.

Abstract: Car while convenient people's life, in traffic safety as a social phenomenon appeared in front of people, brought great influence to force the safe and stable.Someone for traffic safety accident reason, also has caused by irresistible natural forces and other reasons, the human factor in safety accidents accounted for the largest proportion.So the key to prevent traffic accidents is people, also is the driver.Study the influence of the driver of vehicle accidents, in order to strengthen the management of the pilot, can better improve the quality of forces drivers team, promote the development of forces transportation business.

Abstract: Current researches on road network vulnerability (RNV) are mostly focused on its evaluation and calibration, while the classification is rarely studied. For there’s no unanimous and standard criterion in researches on the levels of RNV, it is urgent to find a practical method to define RNV classification for better traffic monitoring and management. In this study, a methodology based on fuzzy clustering is constructed to define the RNV categories. At the same time, this study presents a method to calibrate the availability of such classification. A case study using this methodology is implemented in Xingsha District, Changsha City for determining appropriate RNV categories in the year of 2011. It is found that (1) RNV of this district can be classified into three categories: serious vulnerable level, middle vulnerable level and feeble vulnerable level. (2) links in the artery are at serious vulnerable level of RNV (3) most links are at the middle vulnerable level, so the RNV in the district can be generally defined as at middle vulnerable level.

Abstract: With increasingly fierce competition making price becomes important question relating to the cruise industry. Focusing primarily on three factors, customer arrival rate, ticketing remaining cycles and the remaining tickets, we further improve dynamic pricing method to the market in which we consider random factors and calculate by MATLAB to reflect the impact of three factors on pricing and revenue. It shows that the customer’s arrival rate and the price have the same monotonicity and the more the ticketing remaining cycles are, the lower the price is and the higher the revenue is, and so does the remaining tickets, which is accordance with the actual situation.