Search

This paper presents a traffic volume prediction method for global vehicle path planning at freeway entrances and exits. Firstly, a "point-line" vehicle path planning model was established, and the vehicle driving data was obtained by combining CCD sensor camera. Secondly, the weight of holidays in traffic volume prediction is analyzed from time Angle. The weight and speed in traffic volume prediction are analyzed from the perspective of space, and the weight of vehicle state index is calculated by using adaptive weighted data fusion algorithm. Finally, the traffic volume prediction algorithm is designed to realize the traffic volume prediction of vehicle global path planning. The results show that in the long-term traffic volume forecast results through this method, the Japanese and RMSE are stable at 5.44 and 9.06 respectively and the difference between the daily traffic volume forecast results and the actual results is in 10, which is obviously higher than the comparison method with high accuracy. [ABSTRACT FROM AUTHOR]

Due to the traditional method in the analysis of traffic flow stability, there is no analysis of the influence factors, resulting in the analysis results are not reliable, and cannot accurately analyze the traffic flow in different periods. Therefore, this paper proposes a new type of intelligent network connected vehicle hybrid traffic flow progressive stability analysis method. This method establishes a basic graph model of mixed traffic flow, and analyzes the relationship between traffic flow density, flow and speed through this model. Establish a car-following model to reflect the relationship between the traffic flow and the speed difference, vehicle speed, and headway distance of hybrid intelligent networked vehicles and manually driven vehicles. According to the analysis results, the vehicle collision index, vehicle collision time and vehicle speed dispersion are selected as indicators to analyze the factors affecting the stability of traffic flow, and complete the progressive stability analysis of the mixed traffic flow of intelligent networked vehicles. The results show that the analysis results of this method are highly reliable and can accurately analyze the traffic flow in different periods. [ABSTRACT FROM AUTHOR]

Road traffic is an important factor restricting economic development. With the rapid growth of the number of motor vehicles, traffic accidents, traffic congestion and traffic pollution have become the persistent diseases of contemporary society, and become more and more serious. The existing traffic accident analysis is difficult to comprehensively and objectively reflect the process of traffic accidents. In order to improve the effectiveness of traffic accident prevention and measures, it is particularly important to carry out road traffic accident analysis. The paper proposes a new method for modeling the relationship between vehicle speed dispersion and traffic accidents in mixed traffic flow. Simulation results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In order to overcome the problems of large total vehicle delay and high average absolute error in the process of travel path dynamic planning, this paper proposes a new dynamic planning method of transportation travel path based on Internet of vehicles technology. This method is based on the RFID technology of Internet of vehicles, which makes the electronic tag on the vehicle connect with the traffic network platform to determine the specific position, speed and driving status of the vehicle, so as to identify the behavior track of the vehicle. The vehicle target image is enhanced to estimate the real-time average traffic flow speed of the vehicle driving section. The shortest path of the vehicle driving process is taken as the value function, and the related road path distance is used to complete the dynamic planning of the traffic travel path. The experimental results show that the average total delay of fixed cycle vehicles is 4.604s, which can improve the control effect of traffic lights. The average absolute error value is far less than the existing three methods, and the minimum value can reach 8.13. The predicted value of traffic flow is close to the actual value. [ABSTRACT FROM AUTHOR]

Interchanges are constructed in urban and suburban areas to ease traffic operation. Outer connection ramps constitute a major part of interchanges planning and design. The objective of this study was to estimate interchange ramp capacity and investigate the impacts of ramp geometry on the obtained capacity. To achieve this objective, 20 ramps were selected, including 10 circular ramps and 10 curve-straight-curve ramps. Capacity of ramp proper and ramp exit were investigated in the study. At ramp proper, data on traffic speed and traffic flow were collected at 1 -minute intervals using video camera. Also, traffic data for ramp exit and mainline traffic were obtained under queued traffic condition on the ramp exit. An empirical approach using regression analysis was adopted to estimate capacity of the selected ramps and explore the impact of geometric design and traffic variables that might affect the estimated capacity. For ramp proper, the analyses revealed that the relationship between traffic speed and density is linear and between speed and traffic flow is parabolic irrespective of ramp configuration. For circular ramps, the capacity was found to vary from 1470 to about 2100 pc/hr./lane, and it was found that ramp radius is the most influencing factor in capacity estimation. For curve-straight-curve ramps, the results indicated that the obtained capacity varied from 1490 to 2200 pc/hr./lane, and both the straight segment length and the radius of the first curve are the most influencing factors. Also, it was found that ramp exit capacity is affected by flow and speed of traffic in the mainline street and degree of curvature of ramp exit curve. Finally, it was concluded that the use of curves with large radii at ramp proper and exit would increase ramp capacity, and customization of capacity values to reflect local conditions would provide more realistic estimates. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency and safety of urban expressway, the macroscopic dynamic traffic flow model is extended using speed guidance control. Speed guidance as control variable was introduced into the urban expressway control system, and the macroscopic dynamic traffic flow model was established. Model predictive control is presented to calculate the optimal speed guidance under the objective function of total travel time and changes of speed guidance. Speed guidance control of urban expressway was designed and optimized. Simulation analysis is carried out in simulation platform based on the case of mutations traffic in the downstream. The results show that the speed guidance under safety constraints has a good control effect to smooth traffic flow, alleviate traffic congestion and improve traffic safety which can be applied in practice to provide a theoretical basis for active traffic management [ABSTRACT FROM AUTHOR]

The main objective of this paper is to examine the influence of road alignment on vehicle operating speed. The authors propose and validate a new operating speed model in which the geometric features of an alignment and the lengths of its elements (curve, tangent) are considered. The results demonstrate that grade, radius, and length affect driver perception and operating speeds and are relevant to safety analysis methods. In contrast, the geometric features of previous and oncoming elements, although essential for an accurate analysis of the single locations and sections, had a negligible statistical influence on operating speed. The paper provides a set of analytical tools for predicting driver behaviour and speed in a given section based on the alignment features (previous and oncoming elements included). Furthermore, a framework for ranking and screening the factors that affect speed profiles is presented. Finally, the model can be used in safety evaluation of horizontal curves and tangents on rural undivided roads. [ABSTRACT FROM AUTHOR]

Actively commuting to school gives children the opportunity to explore nature, get exercise, and develop cognitive skills. Today though, few children in the United States (US) are able or given the opportunity to travel to and from school by their own power. Although walking or biking to school was customary 30 years ago, many of today's children are driven to school regardless of the distance. Understanding the barriers that prevent parents from allowing their children to commute to school actively is the first step in encouraging more children to travel by their own power. This study looked at the barriers parents of school children in Illinois, US, reported in the National Safe Routes to School Parent Surveys. The findings indicated that the top barriers for urban and suburban children both included intersection safety and traffic speed/volume, however; distance from school affected suburban students more than urban students. Analysis of parent responses revealed the strongest correlation between speed and volume barriers (r=0.48). With these barriers identified, the Safe Routes to School Programs in Illinois can target their resources effectively to encourage children and their parents to consider walking and biking alternatives for trips to and from school. [ABSTRACT FROM AUTHOR]