scholarly journals Effects of Visual Active Deceleration Devices on Controlling Vehicle Speeds in a Long Downhill Tunnel of an Expressway

2021 ◽  
Vol 11 (15) ◽  
pp. 6753
Author(s):  
Fu Wang ◽  
Dengjun Gu ◽  
Yuanyuan Li ◽  
Wei Liu ◽  
Guoyun Wang
Keyword(s):  
Traffic Safety ◽  
Vehicle Speed ◽  
Road Tunnel ◽  
Obvious Effect ◽  
Average Speed ◽  
Environment Changes ◽  
Fold Line ◽  
Before And After ◽  
Passing Ability ◽  
Tunnel Entrance

Because the inside of a road tunnel is a closed strip, the driving environment changes suddenly at the tunnel entrance and exit, which is why accidents occur more frequently in tunnels than elsewhere. Based on visual psychology, reverse-perspective-illusion deceleration lines (RPIDLs) and visual-intervention deceleration devices (VIDDs) were designed to control vehicle speeds near the entrance and in the middle of a tunnel, respectively. Then, to assess the speed-controlling performance of the RPIDLs and VIDDs for vehicles in a long downhill tunnel, laser velocimeters were used to measure the vehicle speeds at different observation points in the tunnel before and after implementing the RPIDLs and VIDDs. The results show that the RPIDLs and VIDDs decreased the average vehicle speed and controlled its dispersion effectively. The 60 m RPIDLs improved the traffic safety in the tunnel without lessening the passing ability therein. The slash-line VIDD had no obvious effect on the maximum vehicle speeds in the middle of the tunnel. Both the 90° fold-line VIDD and the four-yellow–four-white VIDD decreased the maximum vehicle speeds significantly. The 60 m RPIDLs and the 90° fold-line VIDD gave the best deceleration effect on vehicles near the entrance and in the middle of the tunnel, respectively, and controlled the average speed and its dispersion effectively.

Applicability Analysis and Installation Techniques of Driver Feedback Sign on Freeway in China

2012 ◽  
Vol 209-211 ◽  
pp. 987-991
Author(s):  
Shui Long Jiang ◽  
Hong Qi Liu
Keyword(s):  
Traffic Safety ◽  
Document Retrieval ◽  
Technical Requirement ◽  
Vehicle Speed ◽  
Safety Level ◽  
Before And After ◽  
Feedback Sign ◽  
Driver Feedback ◽  
At Home

The Driver Feedback Sign (DFS) has been widely used abroad to reduce the vehicle speed to improve traffic safety level, but it only be used on a few of freeways and urban expressways in China, and there have no research on its application effect. In order to popularization and application the DFS in China, the paper analyzed the DFS application situation at home and broad by document retrieval, comparatively analyzed implement effect before and after installing DFS on Badaling freeway by vehicle speed survey and questionnaires survey. At last, the paper comprehensively analyzed the applicability of DFS on freeway in China and proposed the installing requirement and technical requirement.

scholarly journals Relationship between Speed Characteristics and Traffic Safety on Freeways in Mainland China

2018 ◽  
Vol 47 (4) ◽  
pp. 318-328 ◽  
Author(s):  
Ziyue Tang
Keyword(s):  
Standard Deviation ◽  
Traffic Safety ◽  
Traffic Accidents ◽  
Mainland China ◽  
Practical Significance ◽  
Vehicle Speed ◽  
Average Speed ◽  
Regression Methods ◽  
Nonlinear Regression Method ◽  
Speed Standard Deviation

Based on the traffic accidents statistical data of 10 typical freeways in mainland China, by using of some kinds of regression model, the influences of the average vehicle speed and the speed standard deviation on the traffic safety are studied. According to the regression results, the accidents show an increasing trend with the increase of the vehicle average speed and the speed standard deviation. On this basis, in view of the regression results, the strategy is put forward for controlling the vehicle average speed and the speed standard deviation, which has important theoretical and practical significance for improving highway safety. After a comprehensive comparison among these regression methods, it is found that the nonlinear regression method of user-defined model expression has the best fitting effect, and it can also more accurately describe the objective reality. It has high practicality and popularized value.

scholarly journals Effects of small-sided games and conventional aerobic interval training on various physiological characteristics and defensive and offensive skills used in soccer

Kinesiology ◽  
2018 ◽  
Vol 50 (1) ◽  
pp. 104-111 ◽  
Author(s):  
İlker Özcan ◽  
Çağatay Şahan
Keyword(s):  
Anaerobic Threshold ◽  
Interval Training ◽  
Endurance Performance ◽  
Physiological Parameters ◽  
Technical Ability ◽  
Aerobic Interval Training ◽  
Before And After ◽  
Analysis System ◽  
The Individual ◽  
Passing Ability

The aim of this study was to investigate the effects of small-sided game training (SSGT) versus conventional aerobic interval training (CAIT) on soccer-specific endurance performance, lactate threshold levels (mmol·L-1), short-passing ability and defensive and offensive skills of a soccer match. Before and after a 6-week training intervention period, eighteen amateur soccer players (age 21.8±4.8 years) were tested. The tests included the anaerobic threshold (AnT) test, the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1), and the Loughborough Soccer Passing Test (LSPT). A manual notational match analysis system was utilized to evaluate the defensive and offensive skills of players during the matches. Both the SSGT and CAIT were performed two days a week and consisted of five sets of 6-minute periods of work at the individualized exercise intensity corresponding to the individual anaerobic threshold, with 3-minute of recovery periods between sets. Mann-Whitney U and Wilcoxon signed rank tests were used to examine the between- and within-group differences, respectively. Statistical analyses revealed that the SSGT group players exhibited significantly better in terms of the LSPT scores (p<.01) and the number of defensive and offensive skills (p<.05). However, no other significant differences in the other variables were observed (p>.05). The results of the study suggested that SSGT improved short-passing ability, various soccer skills and physiological parameters, while CAIT only improved physiological parameters. SSGT improves soccer-specific endurance and technical ability of players at the same time, meaning it is a time efficient way of training.

Road Engineering Optimization Based on Driving Reaction

2013 ◽  
Vol 579-580 ◽  
pp. 841-844
Author(s):  
Zhao Cao ◽  
Xiao Wu ◽  
Qing Yang
Keyword(s):  
Traffic Safety ◽  
Safety Issue ◽  
Heart Beat ◽  
Driving Safety ◽  
Response Analysis ◽  
Vehicle Speed ◽  
Force Coefficient ◽  
Slope Length ◽  
Road Engineering ◽  
Positive Correlation

With the increasingly outstanding of the traffic safety issue, the human factors in People-Vehicle-Road System are being emphasized gradually. Takes Jinhua suburb asphalt mountain road (two-lane, multiple steep slopes) for example, this study focuses on road engineering response analysis on driving reaction, design optimization of road engineering base on driving response. A driver over 3 driving years steered 5-seat car in 4 kilometers long experimental road, kept the vehicle speed (V) under 40km/h. Heartbeat rate of the driver was monitored by dynamic Holter through driving process. The analysis shows that there is a linear positive correlation between Heart beat growth rate (Ni) and V, a nearly positive correlation between lateral force coefficient (μ) and Ni, and nearly inversely proportional between plane curve radius (R) and slope (i). It should decrease R appropriately when road slope (i) much sharply in road alignment design. There is a polynomial relation between Ni, V and R. As R increases, both Ni and V reduce firstly, and then rise. When R ranges from 240 to 500 meter, stress gradually ease; while R exceeds 500 meter, driving reaction tension gradually rise. R<550 m, i <6% and slope length under 300 m in the experimental road. When instructional speed <40km/h, then Ni was 30.2% and μ was 0.25. Its benefit for driving safety to keep drivers in appropriate tension in such situation.

Research on Safety Vehicle Distance Recognition Based on Stereo Vision and DSP

2013 ◽  
Vol 333-335 ◽  
pp. 805-810 ◽  
Author(s):  
Rong Bao Chen ◽  
Ning Li ◽  
Hua Feng Xiao ◽  
Wei Hou
Keyword(s):  
Stereo Vision ◽  
Traffic Safety ◽  
Traffic Accidents ◽  
Intelligent Transportation ◽  
Research Area ◽  
Measurement Range ◽  
Vehicle Speed ◽  
Target Vehicle ◽  
Operation Rate ◽  
The Right

With the development of economy, there are an increasing number of cars as well as traffic accidents, thus intensifying the need to take measures to reduce traffic accidents and protect the safety of life and property. Vehicle distance is one of the most important indexes of traffic safety. The measurement of safety vehicle distance has become an increasingly hot research area of intelligent transportation. Through analyzing the basic principle of stereo vision and calibrating the parameters of the CCD sensors both inside and outside, this paper comes up with a method to measure the former vehicle distance based on stereo vision and DSP. Once the vehicle speed and distance form a non-security association, it will give a warning, and upload data or force speed-limiting. According to the different coordinates of the obtained images of the target vehicle from the left and the right sensor, this method can identify feature points, calculate distance to the target vehicle, and analyze the security of vehicle distance. The experimental results show that this method has wide measurement range, high measurement accuracy, and fast operation rate, thus it can meet the actual needs of the measurement of safe vehicle distance in intelligent transportation.

scholarly journals Evaluation of Automated Enforcement Program in Amman

2018 ◽  
Author(s):  
Hana Naghawi ◽  
Bushra Al Qatawneh ◽  
Rabab Al Louzi
Keyword(s):  
Traffic Safety ◽  
Questionnaire Survey ◽  
Positive Impact ◽  
Red Light ◽  
Crash Frequency ◽  
Red Light Running ◽  
Red Light Cameras ◽  
Percent Confidence Level ◽  
Before And After ◽  
Traffic Violations

This study aims, in a first attempt, to evaluate the effectiveness of using the Automated Enforcement Program (AEP) to improve traffic safety in Amman, Jordan. The evaluation of the program on crashes and violations was examined based on a “before-and-after” study using the paired t-test at 95 percent confidence level. Twenty one locations including signalized intersections monitored by red light cameras and arterial roads monitored by excessive speed cameras were selected. Nine locations were used to study the effectiveness of the program on violations, and twelve locations were used to determine the effectiveness of the program on frequency and severity of crashes. Data on number and severity of crashes were taken from Jordan Traffic Institution. Among the general findings, it was found that the AEP was generally associated with positive impact on crashes. Crash frequency was significantly reduced by up to 63%. Crash severities were reduced by up to 62.5%. Also, traffic violations were significantly reduced by up to 66%.  Finally, drivers’ opinion and attitude on the program was also analyzed using a questionnaire survey. The questionnaire survey revealed that 35.5% of drivers are unaware of AEP in Amman, 63.9% of drivers don’t know the camera locations, most drivers knew about excessive speed and red light running penalties, most drivers reduce their speed at camera locations, 44.4% of drivers think that the program satisfies its objective in improving traffic safety and 52% of drivers encourage increasing the number of camera devices in Amman.

scholarly journals The concept of average speed measurements network in the West Pomeranian

2018 ◽  
Vol 19 (12) ◽  
pp. 238-241
Author(s):  
Katarzyna Sosik
Keyword(s):  
Traffic Safety ◽  
Road Traffic ◽  
Road Transport ◽  
Transport Systems ◽  
Intelligent Transport Systems ◽  
The West ◽  
Accident Rate ◽  
Average Speed ◽  
Intelligent Transport ◽  
Road Traffic Safety

The article presents the concept of implementing a network of average speed measurements in the West Pomeranian. The author focused on solutions of Intelligent Transport Systems to improve the safety of road transport. The first part of the article discusses the state of road traffic safety in the West Pomeranian. In the next part, the solutions of Intelligent Transport Systems used to record the speed of road vehicles and the method of data recording and processing were discussed. In the third part, the accident maps and the locations of the stored sectional speed measurements were analysed, on the basis of which the proposition of places for the implementation of the network of average speed measurements was created due to the high accident rate.

Numerical Simulation on Deformation Features and Filling Efficiency of Channel Goaf Foundation

2013 ◽  
Vol 353-356 ◽  
pp. 3707-3712
Author(s):  
Zhi Dong Zhou ◽  
Hong Bo Zhang ◽  
Xiu Guang Song ◽  
Hong Ya Yue
Keyword(s):  
Numerical Simulation ◽  
Comparative Analysis ◽  
Comprehensive Analysis ◽  
Obvious Effect ◽  
Before And After ◽  
Check Gate ◽  
Deformation Features ◽  
Natural Foundation ◽  
The Stability

For analyzing and evaluating the deformation features of channel goaf foundation and its effect on superstructure, according to the foundation reinforcement engineering of Ji-Liang Channel Check Gate, the comparative analysis on the differential settlement between the unfavorable foundation and natural foundation was performed by numerical simulation with FLAC3D. The computer results showed that the present foundation had obvious effect on the stability and security of the superstructure, so the engineering treatment are needed. Based on technical-economic comprehensive analysis among three treatment methods for strengthening the channel golf foundation with different kinds of filling, the reasonable method is put forward in this paper. By comparing mechanical characteristic of flashboard in channel goaf before and after strengthening, we confirmed the foundation stability of channel goaf and the security of the ground building which can satisfy the long term usage requirements.

scholarly journals School-Aged Pedestrian–Vehicle Crash Vulnerability

2019 ◽  
Vol 11 (4) ◽  
pp. 1214 ◽  
Author(s):  
Kinga Ivan ◽  
József Benedek ◽  
Silviu Ciobanu
Keyword(s):  
Traffic Safety ◽  
Local Level ◽  
Urban Traffic ◽  
Vehicle Speed ◽  
Vehicle Crashes ◽  
Time Intervals ◽  
Local Authorities ◽  
Traffic Crashes ◽  
Triggering Factors ◽  
Pedestrian Crashes

The analysis of pedestrian–vehicle crashes makes a significant contribution to sustainable pedestrian safety. Existing research is based mainly on the statistical analysis of traffic crashes involving pedestrians and their causes, without the identification of areas vulnerable to traffic crashes that involve pedestrians. The main aim of this paper is to identify areas vulnerable to school-aged pedestrian–vehicle crashes at a local level to support the local authorities in implementing new urban traffic safety measures. The vulnerable areas were determined by computing the severity index (SI) based on the number of fatal, serious, and slight casualties throughout the 2011–2016 period in a large urban agglomeration (Bucharest). As well as the vulnerable areas, the triggering factors and the time intervals related to school-aged pedestrian–vehicle crashes were identified. The outcomes of the study showed that the vulnerable areas were concentrated only in districts 2 and 4 of Bucharest, and they were associated with high vehicle speed and pedestrians’ unsafe crossing behavior. The findings revealed that speed and age are triggering factors in generating school-aged pedestrian–vehicle crashes. The identified time peaks with a high number of traffic crashes correspond to the afternoon time intervals, when scholars go home from school. The identification of the areas vulnerable to school-aged pedestrian crashes may help local authorities in identifying and implementing measures to improve traffic safety in large urban agglomerations.

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