On kinematic waves II. A theory of traffic flow on long crowded roads

1955 ◽  
Vol 229 (1178) ◽  
pp. 317-345 ◽  
Keyword(s):  
Traffic Flow ◽  
Functional Relationship ◽  
Vehicle Speed ◽  
Main Road ◽  
The Road ◽  
Traffic Distribution ◽  
Kinematic Waves ◽  
The Subject ◽  
The Mean ◽  
Starting Flow

This paper uses the method of kinematic waves, developed in part I, but may be read independently. A functional relationship between flow and concentration for traffic on crowded arterial roads has been postulated for some time, and has experimental backing (§2). From this a theory of the propagation of changes in traffic distribution along these roads may be deduced (§§2, 3). The theory is applied (§4) to the problem of estimating how a ‘hump’, or region of increased concentration, will move along a crowded main road. It is suggested that it will move slightly slower than the mean vehicle speed, and that vehicles passing through it will have to reduce speed rather suddenly (at a ‘shock wave’) on entering it, but can increase speed again only very gradually as they leave it. The hump gradually spreads out along the road, and the time scale of this process is estimated. The behaviour of such a hump on entering a bottleneck, which is too narrow to admit the increased flow, is studied (§5), and methods are obtained for estimating the extent and duration of the resulting hold-up. The theory is applicable principally to traffic behaviour over a long stretch of road, but the paper concludes (§6) with a discussion of its relevance to problems of flow near junctions, including a discussion of the starting flow at a controlled junction. In the introductory sections 1 and 2, we have included some elementary material on the quantitative study of traffic flow for the benefit of scientific readers unfamiliar with the subject.

On Some Flint Implements Beneath Blown Sand in Northern France

1922 ◽  
Vol 3 (4) ◽  
pp. 587-596
Author(s):  
R. H. Chandler
Keyword(s):  
Sand Dunes ◽  
Main Road ◽  
The Road ◽  
Northern France ◽  
The Subject ◽  
North And South

The implements forming the subject of this note were found at the base of the Blown Sand Dunes which extend along the coast of Pas de Calais and attain, in the neighbourhood of Etaples, a height of 60 metres.The principal sites are grouped about the outstanding pinacle of sand immediately opposite the Etaples Military Cemetery, and are on the east of the road to Boulogne and about one mile out of Etaples.This pinacle of sand is the highest dune seen from the road (it reaches up to about 50 metres) and it is in the dunes ranging north and south of this pinacle, where the wind has scooped out hollows in the western face, and reached down to the underlying chalk and gravel, that the implements and flakes occur so abundantly.Generally speaking there are low dunes bordering the Canche River, but on the east of the main road they rise in a fairly pronounced range to between 40 and 50 metres, then they fall away to about 25-30 metres and rise again, ¼ to ½ a mile further inland to about 60 metres.

CELLULAR AUTOMATON MODELS FOR MIXED TRAFFIC FLOW CONSIDERING PASSAGE WAY OF EMERGENCY VEHICLE

2013 ◽  
Vol 27 (08) ◽  
pp. 1350052 ◽  
Author(s):  
HAN-TAO ZHAO ◽  
HONG-YAN MAO ◽  
RUI-JIN HUANG
Keyword(s):  
Cellular Automaton ◽  
Traffic Flow ◽  
Average Density ◽  
Vehicle Speed ◽  
Emergency Vehicle ◽  
Mixed Traffic ◽  
Mixed Traffic Flow ◽  
The Road ◽  
Emergency Vehicles ◽  
Computer Numerical Simulation

Two kinds of cellular automaton models are proposed for mixed traffic flow with emphasis on emergency vehicles. By analyzing the characteristics of ordinary vehicles in giving way to emergency vehicles, the rules for changing lanes are modified. Computer numerical simulation results indicate that an emergency vehicle without changing lanes can enhance speed with density lower than 0.1, while its speed can be enhanced by changing lane with density greater than 0.1. Meanwhile, vehicle speed and density within a certain range around emergency vehicles are lower than the road section average velocity and average density. The passage way of emergency vehicle that facilitate lane change causes less interference than that of an emergency vehicle which is unable to change lane. The study found that the physical characteristics of traffic flow when there are emergency vehicles are significantly different from routine traffic flow. Emergency vehicles can facilitate their passage by changing lanes at a medium or high density.

scholarly journals Acoustic Road Monitoring

2018 ◽  
Vol 231 ◽  
pp. 05002 ◽  
Author(s):  
Karolina Marciniuk ◽  
Maciej Blaszke ◽  
Bożena Kostek
Keyword(s):  
Traffic Flow ◽  
Monitoring System ◽  
Signal Analysis ◽  
Road Traffic ◽  
Weather Condition ◽  
Audio Signal ◽  
Flow Sensors ◽  
The Road ◽  
The Subject ◽  
Acoustic Representation

The subject of this research is showing the performance of an automatic acoustic road monitoring system proposed by the authors. The main goal of the study is describing road traffic by means of an acoustic representation and testing effectiveness of traffic flow sensors. Evaluation metrics of the road conditions such as velocity of the traffic flow, its structure and weather condition are presented along with acoustic descriptors derived from the audio signal analysis. Accuracy of emergency vehicles pass by detection based on acoustic monitoring is also briefly described.

scholarly journals Performance Analysis of Road Section and Unsignalized Intersections On Jalan Cileungsi Setu and Jalan Raya Narogong

2021 ◽  
Vol 1 (2) ◽  
pp. 72-80
Author(s):  
Muhammad Isradi ◽  
Nandhita Aulia Tarastanty ◽  
Widodo Budi Dermawan ◽  
Amar Mufhidin ◽  
Joewono Prasetijo
Keyword(s):  
Secondary Data ◽  
Population Data ◽  
Degree Of Saturation ◽  
Primary Data ◽  
Vehicle Speed ◽  
Data Traffic ◽  
Main Road ◽  
Saturation Degree ◽  
The Road ◽  
Commercial Area

The unsignalized intersection which is located in Cileungsi District, precisely on Jalan Cileungsi Setu and Jalan Raya Narogong, is a commercial area with dense economic activity and densely populated settlements. As a result of the dense activity, congestion occurs due to the large number of vehicles passing the road, especially during peak hours, namely the morning and evening. Seeing this problem, an analysis is needed that aims to determine the volume, performance of roads, and unmarked intersections as measured by capacity, degree of saturation, and level of service.  In analyzing this study using the Indonesian Road Capacity Manual (MKJI) 1997 method which will determine the performance of roads and intersections without signs. The data needed in this research are primary data in the form of geometric road data, traffic volume, vehicle speed data, and side friction. As well as secondary data in the form of location maps, land use, and population data. From the results of data analysis and processing, the busiest traffic flow at the intersection occurred on Sunday, November 15, 2020 at 17.30 - 18.30 WIB, the saturation degree value was 1.17 with LOS F. By doing an alternative solution, the saturation degree value was 0.68 and LOS B with placing signs are prohibited from stopping around intersections, and prohibiting the flow of traffic turning right either from the main road D to the Minor C road or from the Minor C road to the main road B. On Jalan Raya Narogong, the degree of saturation is 0.74 LOS C service, this shows that the road sections do not exceed the figure required by MKJI 1997, namely ≤ 0.75.

scholarly journals AVERAGE SPEED ENFORCEMENT SYSTEM EFFICIENCY ASSESSMENT MODEL

2017 ◽  
Vol 12 (1) ◽  
pp. 64-69
Author(s):  
Laura Jateikienė ◽  
Audrius Vaitkus
Keyword(s):  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Assessment Model ◽  
Vehicle Speed ◽  
Main Road ◽  
Average Speed ◽  
The Road ◽  
Traffic Law Enforcement ◽  
High Level ◽  
Speed Enforcement

Accidents are one of the leading cause of death all over the world. Speed has been identified as a factor in road accidents, influencing both the risk of accidents and the severity of the accidents. However, speeding is one of the most frequent violations of traffic rules by the road users. Many results of studies showed that the implementation of speed cameras significantly reduced the vehicle speed and the number of accidents near camera sites. One issue regarding speed enforcement by a speed camera is that a reduction in speed is obtained only on a short section of a road. The results of scientific research analysis suggest that this issue can be overcome by the employment of average speed enforcement system (hereafter system), which is a relatively new approach to traffic law enforcement. Until now, Lithuania had no methodology for selecting road sections to be installed with the system. The purpose of this paper is to develop a model for the assessment of safety impact of the system and to perform economic estimation of a system of Lithuanian main road sections selected under this model. The analysis of international practice helped to develop this model, which joins accident indicators, road and traffic parameters. A cost-benefit analysis of the system, implemented on main road sections and selected by suggested model, shows a high level of payback. The implementation of the system would pay back in one year of service.

scholarly journals MODELING AND SIMULATION OF TRAFFIC FLOWS ON INCLINED ROAD DURING EVACUATION PROCESS OF THE VOLCANO DISASTER WITH FINITE DIFFERENCE METHOD

2017 ◽  
Vol 17 (1) ◽  
pp. 8
Author(s):  
Richasanty Septima S ◽  
Said Munzir ◽  
Salmawaty Salmawaty
Keyword(s):  
Finite Difference ◽  
Finite Difference Method ◽  
Traffic Flow ◽  
Difference Method ◽  
Upwind Scheme ◽  
Vehicle Speed ◽  
Traffic Flows ◽  
The Road ◽  
Vehicle Density ◽  
Forward Difference

The research in this thesis was done to examine the model of traffic flow of volcanic disaster evacuation path for uphill and downhill roads. The assessment was focused on the area of disaster evacuation path from the Pante Raya Bener Meriah intersection to Takengon. This model is assessed for two different types of time when which a disaster occurs; the disaster occurred at night and the disaster occurred during the day, especially during peak hours (working hours). The model was developed with attention to the exixtence of inflow and outflow along the evacuation route. Furthermore, the model obtained is solved numerically by using finite difference method. The chosen approach of this method is upwind scheme with time and space steps using forward difference and backward difference. The solution of this model in the form of simulated vehicle density along evacuation pathways. The research conducted is in the form of a model of traffic flow on evacuation paths and restricted to the inflow and outflow without alternative path as well as the conditions of the road which are uphill and downhill, showed a high density of vehicles either at night or during the day. Uphill road conditions resulted in decreased vehicle speed and vehicle density will increase, while downhill road conditions resulted in increased vehicle speed and vehicle density will decrease, meaning that the road conditions which are uphill and downhill will greatly affect the process of evacuation. Degree vehicles of evacuation efficiency occuring at night without an alternative pathway produces a high efficiency so that it can be interpreted that the evacuation process in the evening was successful and runs better than the evacuation process during the day, and this is caused by the existence of vehicles on the road  evacuation process started thus affecting the efficiency levels. Keywords : Traffic flows, finite difference method, upwind scheme method, forward difference, backward difference, greenshield method, uphill road, downhill road.

scholarly journals Analysis of the Impact of Traffic Violation Monitoring on the Vehicle Speeds of Urban Main Road: Taking China as an Example

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Fuquan Pan ◽  
Yongzheng Yang ◽  
Lixia Zhang ◽  
Changxi Ma ◽  
Jinshun Yang ◽  
...  
Keyword(s):  
Probability Density ◽  
Road Traffic ◽  
Maximum Speed ◽  
Vehicle Speed ◽  
Main Road ◽  
The Road ◽  
Before And After ◽  
Traffic Violation ◽  
The Impact ◽  
Monitoring Area

In recent years, there are more and more applications of traffic violation monitoring in some countries. The present work aims to analyze the vehicle speeds nearby road traffic violation monitoring area on urban main roads and find out the impact of road traffic violation monitoring on the vehicle speeds. A representative urban main road section was selected and the traffic flow was recorded by camera method. The vehicle speeds before, within, and after the road traffic violation monitoring area were obtained by the calculation method. The speed data was classified and processed by SPSS software and mathematical method to establish the vehicle speed probability density models before, within, and after the road traffic violation monitoring area. The results show that the average speed and maximum speed within the traffic violation monitoring area are significantly slower than those before and after the traffic violation monitoring area. 70.1% of the vehicles before the road traffic violation monitoring area were speeding, and 80.2% of the vehicles after the road traffic violation monitoring area were speeding, while within the road traffic violation monitoring area, the speeding vehicles were reduced to 15.9%. When vehicles pass through the road traffic violation monitoring area, the vehicle speeds tend to first decrease and subsequently increase. In its active area, road traffic violation monitoring can effectively regulate driving behaviors and reduce speeding, but this effect is limited to the vicinity of the traffic violation monitoring. The distribution of vehicle speeds can be calculated from vehicle speed probability density models.

Malaysian Transverse Rumble Strips: A Review and Recommendations for Practice

2015 ◽  
Vol 73 (4) ◽  
Author(s):  
Mohd Hanifi Othman ◽  
Zaiton Haron ◽  
Mohd Rosli Hainin ◽  
Khairulzan Yahya ◽  
Haryati Yaacob ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Vehicle Speed ◽  
Personal Interview ◽  
The Road ◽  
Literature Source ◽  
Public Work ◽  
Public Work Department ◽  
Recommendations For Practice ◽  
Definition Of ◽  
Optical Vibration

Transverse rumble strips (TRS) is a common choice to reduce vehicle speed and increase driver alertness on roadway. TRS is a series of marked (either flat or raised) transverse bars placed across the road in direction of traffic flow. It functions to assist driver to become aware through optical, vibration and audible effect thus encouraging drivers to reduce speed and increase their alertness in order to face any hazard that may exist ahead. Although often being used, in reality TRS usage in Malaysia still has some aspects that can be improved. The purpose of this paper is to critically review the definition of thermoplastic TRS, its effectiveness, standard guidelines in Malaysia, thermoplastic materials and colour and also to propose the recommendation in regard practice of TRS in order to increase its effectiveness. Besides the available literature source in the light of the latest published findings, personal interview have been done to several authorities which are headquarter and district public work department, local municipal and university regarding TRS application guidelines and practice in Malaysia. The authors synthesize the available findings on the TRS performance and standard guidelines to propose some recommendations for a better application practice of TRS in particular in Malaysia. The proposal of all the findings hopefully would be beneficial to authorities in improving the practices of TRS. 

scholarly journals A Data-Driven Method for Vehicle Speed Estimation

2021 ◽  
Vol 23 (3) ◽  
pp. B165-B177
Author(s):  
Angelo Bonfitto ◽  
Stefano Feraco
Keyword(s):  
Neural Networks ◽  
Estimation Method ◽  
Mean Value ◽  
Estimation Accuracy ◽  
Speed Estimation ◽  
Vehicle Speed ◽  
The Road ◽  
Computing Platform ◽  
Road Condition ◽  
The Mean

This paper presents a method based on Artificial Neural Networks for estimation of the vehicle speed. The technique exploits the combination of two tasks: a) speed estimation by means of regression neural networks dedicated to different road conditions (dry, wet and icy); b) identification of the road condition with a pattern recognition neural network. The training of the networks is conducted with experimental datasets recorded during the driving sessions performed with a vehicle on different tracks. The effectiveness of the proposed approach is validated experimentally on the same car by deploying the algorithm on a dSPACE computing platform. The estimation accuracy is evaluated by comparing the obtained results to the measurement of an optical sensor installed on the vehicle and to the output of another estimation method, based on the mean value of velocity of the four wheels.

Novel Algorithm for Calibrating Speed-Density Model Parameters in Mesoscopic Traffic Simulator

2014 ◽  
Vol 599-601 ◽  
pp. 1891-1896
Author(s):  
Xiao Long Li ◽  
Wen Wu Song ◽  
Zhu Jiang
Keyword(s):  
Traffic Flow ◽  
Road Traffic ◽  
Optimal Algorithm ◽  
Dynamic Change ◽  
Density Model ◽  
Weighted Regression ◽  
Model Parameters ◽  
Vehicle Speed ◽  
The Road ◽  
The Common

This article is on the basis of the classical speed-density model which combines with the complex road traffic flow, to raise a way that using the weighted regression to calibrate speed-density model parameters in mesoscopic traffic simulator. After processing detector data, the densities are taken as the variables; locally weighted regression is used to build a nonparameter relationship for the number of the traffic flow, to calibrate the vehicle speed. The test with a huge amount of factual data shows that the methods proposed in this paper outperforms the common optimal algorithm: simplex method in the vehicles speed estimation precision, and can accurately descript the dynamic change regularity of the road traffic flow.

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