Applied Mechanics and Materials Vols. 587-589

Abstract: Urban expressways play an important role in urban traffic networks. Different from the highway speed-flow-density relationship, the urban expressway has more complicate characteristics. With the traffic stream data collected from loop detectors on different sites of the expressway in Beijing, traffic parameters of traffic speed, density and volume are analyzed. As the relationship of speed flow and density changes remarkably during different period of time, this paper establish a speed-flow-density model during nighttime and daytime separately. The relationship among traffic density, speed and volume are key-points analyzed. The research can provide data support and scientific basis for the design and planning of urban expressway.

Abstract: At the beginning the paper summarizes the research status,models and algorithms of dynamic traffic assignment and analyzes the relationship between dynamic user optimal model and variational inequality.Secondly,a dynamic user optimal model of traffic assignment based on optimal signal timing is established,equivalent model of the variational inequality is built at the same time.Finally,we discuss the superiority of the model and apply this model to a simple example,the results show that the model can improve the network performance significantly.

Abstract: According to the traffic survey data and meteorological data of a certain section between Jinshan and Wuhan on Beijing-HK-Macao Expressway, the change of the weighted average speed and the speed of different vehicle types under different visibility grades was studied, and the linear speed-density model of Green Shields was improved using the method of curve estimation and regression analysis. The results show that the higher the grade of fog, the lower the driving speed, and the effect of fog on speed is even greater for faster vehicles than slower ones. In addition, by adding the two variables visibility and models to the Green Shields model, the accuracy of the model has been improved.

Abstract: Urbanization sweeping the world has greatly increased the speed of urban life, and cars become the development trend of modern city. As a consequence, there is a growing number of contradictions within the systems of urban traffic. This article conducted traffic surveys in the West Second Ring road of Hohhot and analyzed the collected traffic data. Analysis to identify the existing problems of the Second Ring Road through the traffic parameters, given the optimization proposal based on the status, simulated the optimization method by VISSIM simulation software as while.

Abstract: With a sustained growth of cars, many urban traffic problems caused by cars should be solved as soon as possible. However, basic urban traffic investigation and analysis of current situation is the the basis and the key to solve the problems. In this paper, investigation of traffic volume and pot speed is done at DongYing Road in Hohhot, and basic data base is established. Some significant parameters of urban traffic are calculated, and current traffic situation of the investigated road is detailedly analysed and studied. What is more, some problems found during the investigation are proposed and corresponding feasible suggestions are given.

Abstract: This paper integrated superiority from time series model and least square support vector machine regression model with data aggregation for traffic speed short term forecasting. Based on the results of traffic data variations analysis, the practicability that speed data can be aggregated to several periods was confirmed, and aggregated model can be developed to forecast the speed with auto regression (AR) model and support vector machine regression (SVR). Then the speed data in case study were integrated to 4 periods at the location of Remote Traffic Microwave Sensors (RTMS) 2047 on 2^nd Ring Road Expressway in Beijing. Arguments with coefficients from AR models then act as the independent variables of LSSVR in aggregated model. Short term traffic speed was predicted by aggregated model, and the results indicated that taking advantages of time periods variation rule inside the aggregated model would help save the model running time cost under the premise of accuracy with better prediction ability than LSSVR in certain conditions.

Abstract: According to the operation status of the transportation enterprise in our country, choose financial benefit, asset operational condition, debt paying ability and development ability as a benefit evaluation system. In order to achieve the goal of comprehensive evaluation, the Extension Matter-element Model is applied to the benefit evaluation field. And correlation function is used to represent the benefit of transportation enterprise.Through the comprehensive level evaluation of transportation enterprise benefit, we analyze the reasons for the poor financial results of enterprise and corresponding improving measures are put forward according to the results of the evaluation.

Abstract: This paper aimed at the freeway entrance ramp control principles, through introduction of dynamic adjustment system of the entrance ramp and the control algorithm of the difference between traffic demand and capacity, a problem of the dynamic adjustable rate’s selection was proposed, then used the micro-simulation tool VISSIM to analysis the influence of dynamic adjustable rate that under different capacity reduction factors, choosing delay time and travel time as the standard of entrance ramp control system. At last, this paper concludes that the best reduction factor is 0.98 times the capacity.

Abstract: As an important part of the urban vehicle network, Bus Mobility Vehicle Network provides supports for a wide range of urban-vehicle communication network due to cyclical movement feature. However, the high-speed mobility brings great challenges to Bus Vehicle Network routing protocols. The paper aims Bus Mobility Vehicle Network with the characteristics of cyclical movement, and put forward to Single & Multi hop Routing (SMHR) routing protocol program. Link Survival Mode will be established in Single-hop to select encounter nodes as forwarding candidate set. Discrete Stochastic Dynamic Programming Delay Probability Model will be established in Multi-hop using the historical data of bus cyclical movement. The two model ensure the submitted data reliable in single-hop, and probability of successfully submitted to the target vehicle through multi-hop data within a limited delay. According to the simulation test, SMHR protocol has a higher successful rate of data transmission and lower submitted delays.

Abstract: This article aims at to invent a warning system which can be used to improve the widely spread phenomenon of pedestrians and non-motorized vehicles’ traffic violation in our country. We collected data by making researches at the cross between the North and South terminal coach station of Jinan. Analysis of psychological knowledge causes pedestrian and non-motorized vehicle traffic violation are expounded in detail.