MODELS OF TRAFFIC FLOW DYNAMICS ON HIGHWAYS

2021 ◽  
Vol 116 (1) ◽  
pp. 236-241
Author(s):  
Diana Assankhankyzy Otegen
Keyword(s):  
Transport Infrastructure ◽  
Macroscopic Model ◽  
Flow Density ◽  
Traffic Flows ◽  
Macroscopic Models ◽  
The Road ◽  
Advantages And Disadvantages ◽  
Space And Time ◽  
Microscopic Models ◽  
On The Road

The paper is an analytical review of the currently existing methods of traffic flows modeling. The movement of vehicles on the road can be modeled in different ways. Mathematical models as tools that allow us to study complex processes in the real world, including transport infrastructure, without capital expenditures, are a popular tool for solving many problems in various spheres of the national economy. There are several approaches to mathematical modeling of traffic flows. In microscopic models, the law of motion of each car is set, depending on its current position, speed, characteristics of the movement of neighboring cars, and other factors. Microscopic models, in turn, can be divided into models that are continuous in space and time, and into models that are discrete in space and time, the so-called cellular automata. In macroscopic models, the transport flow is considered as a fluid flow with special properties. The equations of the macroscopic model establish the relationship between the flow, density, speed of movement, possibly acceleration, and so on. Macroscopic models can also be continuous or discrete. In continuous models, the change in the state of a road section without branches and intersections is usually described by partial differential equations. Modeling traffic flows is necessary because active experiments in the existing transport network are fraught with unpredictable consequences, and in many cases are not feasible at all. The work presents a description and analysis of the models, and of their advantages and disadvantages.

scholarly journals CLASSICAL PHOTOGRAMMETRY AND UAV – SELECTED ASCPECTS

2016 ◽  
Vol XLI-B1 ◽  
pp. 947-952 ◽  
Author(s):  
S. Mikrut
Keyword(s):  
Aerial Images ◽  
Relevant Research ◽  
The Road ◽  
Advantages And Disadvantages ◽  
Subpixel Accuracy ◽  
Low Costs ◽  
On The Road ◽  
Uav Images ◽  
The One ◽  
Research Centres

The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical) height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km<sup>2</sup>) for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle). Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy). After initial pre-processing of data, the images were put together, and shown side by side. Buildings and strips on the road were selected from whole data for the comparison of edges and details. The details on UAV images were not worse than those on classical photogrammetric ones. One might suppose that geometrically they also were correct. The results of aerotriangulation prove these facts, too. Final results from aerotriangulation were on the level of RMS = 1 pixel (about 3 cm). In general it can be said that photographs from UAVs are not worse than classic ones. In the author's opinion, geometric and radiometric qualities are at a similar level for this kind of area (a small village). This is a very significant result as regards mapping. It means that UAV data can be used in mapping production.

TRAFFIC FLOWS MODELING WITH INACCESSIBLE FOR DRIVING ROAD SECTIONS

2021 ◽  
pp. 19-36
Author(s):  
Anastasiya N. Zhukova ◽  
◽  
Marina S. Shapovalova ◽  
Keyword(s):  
Network Formation ◽  
Road Transport ◽  
Traffic Density ◽  
Traffic Flows ◽  
The Road ◽  
Model Modification ◽  
Road Section ◽  
Transport Line ◽  
On The Road ◽  
Python Programming

Computerized traffic modeling makes it possible to find out the modification needs to assess the traffic flow on the roads and detect likely problem areas in order to take timely measures to eliminate them. Competent preparation of a road network formation plan based on the acquired information makes it possible to reduce the load on the road transport line, avoid traffic jams, and also reduce the average time spent by drivers on the roads. The macroscopic and microscopic models of the cars flow were analyzed by authors to implement the computer model. The article considered the model of the cellular automata by Nagel–Schreckenberg, with the author’s addition that takes into account the presence of the road sections inaccessible for driving in. The need to modify the lane change algorithm was implemented: the condition of the need to change the lane when car is meeting an inaccessible road section was added. And also the “polite” drivers algorithm for bypassing inaccessible areas with a high density of the traffic flows was proposed. Such a model is realized on Python programming language. An analysis of vehicles behavior with different traffic density and location of inaccessible road sections for two- and three-lane roads was carried out based on that model modification.

scholarly journals FOURIER ANALYSIS OF THE TRAFFIC FLOW INTENSITY

2021 ◽  
pp. 46-59
Author(s):  
M.G. Boyarshinov ◽  
◽  
A.S. Vavilin ◽  
A.G. Shumkov ◽  
◽  
...  
Keyword(s):  
Time Series ◽  
Fourier Series ◽  
Traffic Flow ◽  
Harmonic Functions ◽  
Traffic Flows ◽  
The Road ◽  
Flow Intensity ◽  
Software And Hardware ◽  
On The Road ◽  
Amplitude Characteristics

The relevance of this work is determined by the need to find modern ways to process the information about traffic flows for regulating and controlling the movement of transport and pedestrians, to reduce congestion, road accidents, etc. The object of study is a part of road with heavy two-way traffic, equipped with a software and hardware complex that allows to measure the characteristics of the transport flow. The subject of the study is the daily intensity of the cars flow during the week, from Monday to Sunday. The purpose of this study is to analyze the amplitudes, frequencies, and periods of harmonic functions obtained by decomposing the time series of road traffic intensities to identify the main patterns of traffic flow formation. As a theoretical and methodological approach, the decomposition of the function of the traffic flow intensity in the Fourier series with respect to harmonic functions is used. The approach developed by the authors using the fast Fourier transform procedure made it possible to determine the amplitude-frequency characteristics of the time series under consideration, which is a scientific novelty of the analysis. It is proposed to use the «period-amplitude» characteristics as physically more meaningful instead of the «frequency-amplitude» dependencies traditionally used for the analysis. The processing of data obtained from software and hardware complexes allowed us to determine dependences of the car flow intensity on the road of the Perm city at different averaging intervals, to describe the features of the motor transport movement on the road under consideration. As a result of the study, the amplitude-frequency characteristics of time series are obtained. It is shown that the individual harmonics of the Fourier series expansion of the traffic flow intensity, which exhibits the properties of a random function, duplicate the periodicity of the global, local, and intermediate extremes of the original function and have similar periods. The practical significance consists in the use of the decomposition of the function of the traffic flow intensity in the Fourier series of harmonic functions for predicting traffic flows, controlling the operation of traffic lights, monitoring the operation of equipment, as well as in the reconstruction, design and construction of roads and road objects. The study will continue in the direction of obtaining, processing and determining the «period-amplitude» characteristics for time series of traffic flow intensity for other road networks.

scholarly journals Overview of approaches to driver fatigue recognition and existing technical solutions

2020 ◽  
Vol 1 (3) ◽  
pp. 48-58
Author(s):  
Ya.D. Saprykin ◽  
◽  
V.I. Ryazantsev ◽  
A.A. Smirnov ◽  
◽  
...  
Keyword(s):  
Traffic Accidents ◽  
Road Traffic ◽  
Physiological State ◽  
Steering Wheel ◽  
Driver Fatigue ◽  
The Road ◽  
Advantages And Disadvantages ◽  
Falling Asleep ◽  
On The Road ◽  
Technical Solutions

The article analyzes the existing methods for determining the driver's condition. Driving in a state of fatigue, according to various statistics, is the cause of a large number of road traffic accidents (RTA). The percentage of accidents in Russia associated with the driver falling asleep while driving in 2018 is about 20%, in the USA the number of accidents for the same reason reaches 100,000 per year. The aim of the work is to review existing approaches to recognizing driver fatigue and existing technical solutions in this area. The article discusses such approaches as fatigue recognition based on the physiological state of the driver, recognition based on the driver's behavior, namely his speech and visual signs while driving, fatigue determination based on the nature of the vehicle's movement on the road and based on the driver's actions on the controls, the approaches based on the subjective assessment of the driver's condition. The advantages and disadvantages of each of the approaches were analyzed. The paper also provides an overview of existing fatigue recognition systems from various manufacturers that are currently used on vehicles and are designed to warn the driver of impending fatigue. It was revealed that in modern conditions of road transport operation, the most optimal approaches to fatigue recognition are based on an assessment of the driver's impact on the steering wheel, visual signs of driver fatigue and the nature of the vehicle's movement on the road, therefore, it is proposed to further focus on these methods.

scholarly journals Assessment of Colorimetric Parameters for HPS Lamp with Electromagnetic Control Gear and Electronic Ballast

Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2909
Author(s):  
Roman Sikora ◽  
Przemysław Markiewicz
Keyword(s):  
New Technologies ◽  
Technical Condition ◽  
Road Accident ◽  
Electronic Ballast ◽  
The Road ◽  
Advantages And Disadvantages ◽  
Road Lighting ◽  
Road Users ◽  
Electromagnetic Control ◽  
On The Road

Road lighting is an important element of road infrastructure influencing on the road safety. It helps road users to identify potential hazards on the road and reduces the risk of a road accident. Improving the energy efficacy of road lighting installations requires using new technologies. Currently, high-pressure sodium (HPS) lamps are still most commonly used in road lighting. Many of the luminaires with HPS lamps are still in good technical condition and there is no economic justification for replacing them (except improving energy efficacy). One of the methods of improving their energy efficacy is to replace the electromagnetic control gear (ECG) with an electronic ballast (EB). This replacement may affect the colorimetric parameters of the HPS lamps. Two methods to the estimation change of colorimetric parameters after the replacement of ECG to EB were used. The first is CIE TN 001:2014 and the second is ANSI/IES TM-30-15. The article also presents the advantages and disadvantages of these methods in relation to the evaluation of changes in colorimetric parameters of HPS lamps after the replacement of the ECG with an EB. After the replacement of ECG to EB, the smallest reduction of Ra (colour rendering index) occurred for the 150 W lamp by 31.30% and the highest reduction for the 70 W lamp by 65.52%. Considering the changes of the fidelity indicator Rf and gamut indicator Rg, their changes are significantly smaller than for Ra. The smallest change of Rf value was observed for a 150 W lamp (6.00%) and the largest for a 70 W lamp by 25.00%. In case of Rg, similar changes were observed—for 150 W lamp by 9.26% and for 70 W lamp by 21.88%. The ANSI/IES TM-30-15 method is more suitable for evaluating colorimetric parameters after replacing ECG with EB. Using only Ra to evaluate changes of HPS lamps colorimetric parameters after replacing the ballast type can lead to incorrect conclusions concerning changes of colorimetric parameters. Based on the ANSI/IES TM-30-15 method, it has been proposed to introduce the Δf,g indicator which determines the change of colorimetric parameters based on fidelity and gamut colour indicator.

OBJECT RECOGNITION SYSTEM ON THE ROAD

2016 ◽  
Vol 3 (1) ◽  
pp. 224-227
Author(s):  
Жданова ◽  
O. Zhdanova ◽  
Макарова ◽  
I. Makarova
Keyword(s):  
Object Recognition ◽  
General Scheme ◽  
Recognition System ◽  
The Road ◽  
Advantages And Disadvantages ◽  
Recognition Systems ◽  
On The Road ◽  
Objects Detection ◽  
Detection And Recognition

This article outlines the existing safety problems on the road, describes the existing recognition systems of well-known automobile manufacturers, and considers advantages and disadvantages of existing solutions. The general scheme of solving the problem of objects detection and recognition was showed.

Optimal Eco-Approach Control With Traffic Prediction for Connected Vehicles

2018 ◽  
Author(s):  
Yunli Shao ◽  
Zongxuan Sun
Keyword(s):  
Robust Optimization ◽  
Optimization Problem ◽  
Traffic Prediction ◽  
Flow Density ◽  
Optimization Approach ◽  
Connected Vehicle ◽  
State Variables ◽  
Unified Framework ◽  
The Road ◽  
On The Road

This work proposes a unified framework for the eco-approach application that integrates traffic prediction, vehicle optimization, and implementation. The eco-approach application is formulated as either a car-following optimization problem or a single vehicle optimization problem, depending on whether a preceding vehicle exists. The traffic prediction scheme anticipates future traffic conditions and describes the traffic dynamics on the road segment of interest using state variables: traffic flow, density, and speed. With the information enabled by connectivity, the traffic state estimation is updated using an observer. Uncertainties in the traffic prediction are considered using a robust optimization approach. The robust optimization problem is discretized and solved by an efficient nonlinear programming solver. The proposed eco-approach framework is implemented to a single lane single intersection scenario for 12, 8, 4, and 1 connected vehicle scenarios. The fuel benefits vary from 11.0% to 6.7% as the penetration rates of connectivity decrease. The performance is satisfactory compared to the 12.0% fuel benefits with perfection traffic prediction.

scholarly journals MODELLING TRAFFIC FLOWS USING GRAPH THEORY

2010 ◽  
Vol 2 (6) ◽  
pp. 86-89
Author(s):  
Oksana Musyt ◽  
Oksana Nadtochij ◽  
Aleksandr Stepanchiuk ◽  
Andrej Beljatynskij
Keyword(s):  
Graph Theory ◽  
Network Optimization ◽  
Road Network ◽  
Traffic Accidents ◽  
Road Transport ◽  
Traffic Flows ◽  
Urban Road ◽  
The Road ◽  
Traffic Jams ◽  
On The Road

An intensive increase in road transport, particularly individual, in recent years has led to such consequences as increased time spent on travel, the number of forced stops, traffic accidents, the occurrence of traffic jams on the road network, reducing traffic speed and a deteriorated urban road network in cities. The most effective method for solving these problems is the use of graph theory, the main characteristics of which is reliability, durability and accessibility of a free as well as loaded network. Based on their analysis the methods for network optimization are proposed.

MODELING TRAFFIC FLUCTUATIONS AND CONGESTION ON A ROAD NETWORK

2015 ◽  
Vol 18 (03n04) ◽  
pp. 1550009 ◽  
Author(s):  
E. ANDREOTTI ◽  
A. BAZZANI ◽  
S. RAMBALDI ◽  
N. GUGLIELMI ◽  
P. FREGUGLIA
Keyword(s):  
Numerical Simulations ◽  
Road Network ◽  
Statistical Physics ◽  
Transition Probabilities ◽  
Traffic Load ◽  
Flow Density ◽  
The Road ◽  
Random Transition ◽  
Emilia Romagna Region ◽  
On The Road

Statistical mechanics points out as fluctuations have a relevant role for systems near critical points. We study the effect of traffic fluctuations and the transition to congested states for a stochastic dynamical model of traffic on a road network. The model simulates a finite population that moves from one road to another according to random transition probabilities. In such a way, we mimic the traffic fluctuations due to the granular feature of traffic and the dynamics at the crossing points. Then the amplitude of traffic flow fluctuations is proportional to the average flow as suggested by empirical observations. Assuming a parabolic shaped flow-density relation, there exists an unstable critical point for the road dynamics and the system can perform a phase transition to a congested state, where some roads reach their maximal capacity. We apply a statistical physics approach to study the onset congestion and we characterize analytically the relation between the fluctuations amplitude and the appearance of congested nodes. We verify the results by means of numerical simulations on a Manhattan-like road network. Moreover we point out the existence of oscillating regimes, where traffic oscillations back propagate on the road network, whose onset depend sensitively from the traffic fluctuations and that have a strong influence on the hysteresis cycles of the systems when the traffic load is modulated. The comparison between the numerical simulations and the empirical traffic data recorded by an inductive-loop traffic detector system (MTS system) on the county roads of the Emilia Romagna region in Italy is shortly discussed.

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