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In recent years, traffic congestion has become an urgent urban problem especially in populated cities like Beijing, Shanghai, etc. There are quite a few explanations towards this problem, but the studies of network and failure implies increasingly evident that the problem is caused by both fixed and dynamic bottlenecks in the network. In this paper, the study focuses on the identification of the fixed and dynamic bottleneck of networks based on the traffic data from a part of road network in Beijing. According to the data view, the dynamic traffic bottleneck recognition is conducted, mainly considering the congestion evaluation under reliability through network topology analysis method. The predictive results can be helpful in applications to formulate the strategy of management and control.

Most k-nearest neighbor models only focus on single step short-term traffic forecasting and can't perform well when extended to multi-step forecast. To enhance accuracy, this paper presents an improved k-nearest neighbor model considering the spatiotemporal correlation. The proposed model defines the current conditions by the two-dimensional spatiotemporal state matrices, instead of the one-dimensional state vector of the time series. Moreover, this paper determines the weights by Gaussian function to adjust the matching distance and manage the data of the nearest neighbors. The original speed data used in this paper are normalized in order to apply the proposed model to different types of road segments. The case shows the improved model performs more desirable than the original k-nearest neighbor models and demonstrates more appropriate for multi-step forecast of the road speed.

To analyze the effect of crosswind on the handling stability of tractor semi-trailers in double-lane change situations, the tractor semi-trailer model and the relative aerodynamic coefficient model were built by using TruckSim. Considering the factors of different crosswind directions, crosswind speed, and vehicle speed, we analyzed the relationship between these factors and the handling stability of tractor semi-trailers in double-lane change situations. The results show that a trailer has movement delay and worse handling stability compared to a tractor. The tractor/semi-trailer is unstable when the vehicle speed is 75 km/h and the crosswind speed is 40km/h or 60km/h. The tractor semi-trailer is stable when the vehicle speed is 70 km/h and the crosswind speed is less than 60km/h.

To analyze the influence of trailer length on passing ability of double semi-trailer road train (B-Train), we built B-Train model by using TruckSim, and confirmed limit steering wheel angle when all wheels of B-Train moved forward and the turning radius was minimum simultaneously by choosing dry pavement. And then, the turning process was simulated to analyze the relationship between the trailer length and the turning channel width at low speed. The results show that increasing trailer length leads to the increase of the turning channel width of B-Train; the turning channel width is larger when the length of the first trailer is increased independently than that when the length of the second trailer is increased independently. In addition, according to the simulation results, we built the relation model between trailer length variation and turning channel width using least-square theory.

Based on the theory and research methods of binocular vision, mechanical structure design and human-machine engineering, the portable investigation system in traffic accident scenes is designed and established. This system is composed of two ordinary fixed focus cameras, control and display unit, connection platform and other accessories, which is convenient(scale-free), accurate and portable for quick investigation of traffic accident scenes.

Modern world builds on the resilience of interdependent infrastructures characterized as complex networks. Recently, a framework for analysis of interdependent networks has been developed to explain the mechanism of resilience in interdependent networks. Here we extend this interdependent network model by considering flows in the networks and study the system's resilience under different attack strategies. In our model, nodes may fail due to either overload or loss of interdependency. Under the interaction between these two failure mechanisms, it is shown that interdependent scale-free networks show extreme vulnerability. The resilience of interdependent SF networks is found in our simulation much smaller than single SF network or interdependent SF networks without flows., Comment: 5 pages, 4 figures

By taking Visual C++ and OpenCV as tools and processing video image sequences gathered by one camera under low view angle, suitable foreground detection method of intersection was selected. Through improving blob tracking system provided by OpenCV, the program was developed to detect motion parameters of vehicles in intersection. The motion parameters were smoothed by Kalman filter. It made the data more reliably. The research could be applied in detections of the traffic conflict and traffic information.

Parameters calibration constitutes the base of car following simulation by Desired Safety Margin(short for DSM model) . In the paper, the DSM model is introduced firstly. Then, the calibration method of the key parameters, including desired safety margin, acceleration and deceleration sensitivities, is proposed. Subsequently, based on driving performances of eight different drivers, with the statistical calculation and analysis, the calibrated parameters, upper and lower limits of desired safety margin, acceleration and deceleration sensitivities, are obtained. After that, with the calibrated DSM model, the application and simulation of a practical car following case are showed. Finally, the main research results are concluded.