Traffic Flow Composition Research Articles

ACOUSTIC POLLUTION OF CITIES AND ITS IMPACT ON HUMAN LIFE ACTIVITIES

The results of acoustic measurements and sociological studies indicate that the main source of acoustic pollution in cities is motor vehicles. About one in two city residents suffers from the noise it generates. Imperfect legislative and regulatory framework, lack of economic instruments to regulate acceptable levels of noise is the reason for the growth of acoustic pollution in cities. The most investigated is industrial noise, while the problem of urban street noise is less studied. It is very difficult to study street noise because this type of noise can originate from a large number of sources. The aim of the study was the measurement of noise pollution and its mode within two cities of different countries. In particular, it is the review of the processes of noise pollution impact on human health and the environment, analysis of the current state of noise pollution in urbanised territories, as well as the identification of modern mechanisms for solving noise pollution issues in urbanised territories. Research methods: field measurements of acoustic pollution levels, analysis, statistical processing of research results, generalisation. Measurements of the maximum level of sound were carried out with the help of FLUSET-965 device. Measurements were conducted according to the standard methodology. The dynamics of noise pollution in the streets of Holosievsky district of Kyiv in comparison with the streets of Cologne, Germany allows us to understand that the type of road surface, traffic intensity, organisation and composition of traffic flow has a significant impact on the level of noise pollution. The methods of calculation of the expected noise level of road transport can be taken as a basis for the selection of building-acoustic measures for protection of residential premises and public buildings from transport noise.

A preliminary analysis for determining passenger car equivalent value for motorcycle during first lost time and saturation time at pretimed signalized intersections

In Banda Aceh City, signalized intersections are a strategic approach to mitigate conflicts such as accidents and traffic congestion. This was achieved by efficiently managing the flow of vehicles passing through intersections, enhancing their overall capacity. Currently, the management of signalized intersections in Banda Aceh still adheres to the guidelines stipulated in the 1997 Indonesian Highway Capacity Manual (MKJI 1997). Given the considerable variation in driver behavior and vehicle composition, particularly motorcycles, within Banda Aceh, a need for updated practices arises. Therefore, this research determined the comparison of PCEs values at the initial and saturation time based on the PKJI 2023 and the new calculations. It was conducted at four-legged intersections, namely Pocut Baren, AMD, Lhong Raya, and Jambo Tape. The primary dataset comprised intersections geometry, effective green time, traffic flow composition captured through drone recordings, and signal configurations. Statistical analysis in this research used multiple linear regression analysis to estimate the Passenger Car Unit (PCU) model parameters using video data recorded at the four-legged intersections. The result showed that PCE values for motorcycles during the initial time was 0.16, higher than the average saturation time values of 0.08.

A mixed traffic car-following behavior model

With the advancement of communication and autonomous driving technologies, a mixed traffic flow comprising human-driven vehicles (HVs), connected human-driven vehicles (CHVs), and connected autonomous vehicles (CAVs) is emerging. In this paper, we propose a generalized car-following model for mixed traffic flow, which considers both the human drivers’ characteristics (i.e., perception ability of distance, acceleration, and speed, trust level in connected vehicle information, and driving style) and information from multiple leading connected vehicles (CVs). Through numerical experiments, we analyze the influences of mixed traffic flow composition schemes, communication distance, and human drivers’ characteristics on mixed traffic flow. The results show that the proposed model can effectively capture the car-following behavior of different types of vehicles in mixed traffic flow. The contribution of CHVs to mixed traffic flow stability is significantly less than that of CAVs due to the involvement of human drivers’ characteristics. Human drivers’ characteristics significantly influence average fuel consumption (FC) within mixed traffic flow. Specifically, inaccurate perception of distance by human drivers can lead to an increase in the average FC, while a higher level of trust in connected information leads to lower average FC. Furthermore, the results reveal that the communication distance between CVs plays a pivotal role in the stability of mixed traffic flow.

Обеспечение эксплуатационной надежности при проектировании автомобильных дорог в условиях Сибири и крайнего севера

Complex natural and climatic, unfavorable soil-hydrogeological and cryogenic conditions of Siberia and the Far North require a special approach to the design of road structures. Taking into account the prediction of climate changes, the intensity and composition of traffic flow, a number of uncertainties arise at the design stage, which can lead to an unrealistic unaccounted picture during the operation of the highway. The article presents the criteria of operational reliability, the results of forecasting and changes in the operational characteristics of highways in the life cycle. It also provides the results of geo-radar surveys on the sections of operated highways, and concerns with the main provisions of ensuring operational reliability in the design of highways in Siberia in the II and III road-climatic zones. The results of the research give the recommendations for the conditions of the Far North. They are able to ensure operational reliability with a staged position requiring additional in-depth monitoring surveys.

Application of Wireless Magnetic Sensors in the Urban Environment and Their Accuracy Verification.

In a smart city, sensors are essential elements-the source of up-to-date traffic information. This article deals with magnetic sensors connected to wireless sensor networks (WSNs). They have a low investment cost, a long lifetime, and easy installation. However, it is still necessary to disturb the road surface locally during their installation. All road lanes to and from the city center of Žilina have sensors that send data at five-minute intervals. They send up-to-date information about the traffic flow's intensity, speed, and composition. The LoRa network ensures the data transmission, but in the event of failure, the 4G/LTE modem realizes the backup transmission. The disadvantage of this application of sensors is their accuracy. The research task was to compare the outputs from the WSN with a traffic survey. The appropriate method for the traffic survey on the selected road profile is a video recording and speed measurement using the Sierzega radar. The results show distorted values, mainly for short intervals. The most accurate output from magnetic sensors is the number of vehicles. On the other hand, traffic flow composition and speed measurement are relatively inaccurate because it is not easy to identify vehicles based on dynamic length. Another problem with sensors is frequent communication outages, which cause an accumulation of values after the outage ends. The secondary objective of the paper is to describe the traffic sensor network and its publicly accessible database. In the end, there are several proposals for data usage.

Development of crash prediction models by assessing the role of perpetrators and victims: a comparison of ANN & logistic model using historical crash data

Road traffic injuries cost countries 3% of their annual GDP. In developing countries like India, every year around 150,000 people die on roads. The type of vehicles involved in a crash contribute majorly to the outcome of casualty (injury/death). Barring few studies, literature are less regarding the role of vehicle as perpetrator and victim on road crash fatalities. Historical crash data has been used in the present study to examine the role of vehicles (both as perpetrator & victim). The study reveals that victim’s effect is more as compared to perpetrator/accused for determining the outcome of crash. Heavy vehicles as perpetrator, and self-hitting vehicles along with pedestrians as victims have higher fatality rates. Binary logistic regression and artificial neural network (ANN) has been utilized for developing prediction models. Binary logistic model predicted around 75% of outcomes correctly with default cut-off value (0.5). However, based on reported crash data, where 19% of total crashes lead to deaths, 0.19 has been proposed as cut-off value which increases the accuracy of the predictions. Accuracy of ANN technique directly depends on the number of crashes reported for a definite pair of perpetrator and victim and the type of validation technique used (Holdback/K-Fold) along with the type of hidden layer chosen for the study based on different types of sigmoid activation function. ROC curves in ANN suggest that the analysis can predict 75% of the outcomes which can be increased by deleting the pairs of vehicles which are present/have occurred in very less number. A comparison has been made between the two techniques based on their advantages and limitations. The developed models can be used as safety indicators based on composition of traffic flow on urban roads.

Standard Axle Loads in the Design of Motorway Pavements

The paper considers issues of standard axle load, which is among the main design parameters when designing motorway pavements. Changing standard axle loads over time due to changes in the traffic flow composition is shown. Standard axial loads recommended for the design by the currently valid regulatory documents are given. Also, axle loads are given for trucks most widespread on domestic highways. Attention is drawn to the axle loads of modern vehicles, significantly exceeding the standard values. Also, the paper provides research data showing that more than 75 % of freight vehicles are overloaded, which also increases axle loads. These two factors – axle loads exceeding the standard values and overloaded vehicles lead to additional loads on the motorway pavement, for which it has not been designed. This, in turn, leads to the premature destruction of road pavements, the loss of their service quality, and additional costs for repairs. The paper justifies the need to increase the standard axle load when designing the motorway pavements since the use of the currently adopted value of 115 kN in the pavement design leads to insufficient strength of the pavement designed and its inability to withstand the existing loads. It is proposed to use an axial load of 150 kN as a design parameter when designing the motorway pavements.

Assessment of the noise level on arterial streets depending on traffic flow indicators

The intensity of traffic flows increases every year and intensifies its impact significantly on urban territory's ecologic situation and natural environment. In Ukrainian cities, the growth of noise pollution is quite a topical problem as it has a significant impact on the environment because of the increase in car numbers. Traffic flow intensity and densification of the built-up area cause the increase of the noise level. As analytical methods of calculation of determination of traffic noise level have several disadvantages, then for assessing the level of noise on arterial streets of Lviv city, research is carried out with consideration of traffic flow indicators. One of the critical criteria that have an impact on noise pollution in the urban environment is traffic flow composition. Conducted research indicates that the speed of traffic flow creates significant noise pollution, especially on those streets where cobblestone is a road pavement. Freight and passenger transport that moves along arterial streets causes the increase of noise level and increases its impact on the city territory. On sections of arterial streets in peak periods of the day with high values of volume-capacity ratio and general share of freight and public transport of more than 30% in a flow, the noise exceeds the acceptable norms and has a harmful impact on the environment. That is why it is necessary to assess noise pollution and the development of protection measures from noise during the planning and construction of some urban regions or residential areas. It is established that to lower the noise level on streets, it is necessary to consider existing intersections of arterial streets and the regime of movement on them. To lower transport noise, it is necessary to distribute freight and transit transport by city streets more rationally, use qualitative public transport, and limit the maximal speed regime on city streets. Further research on the road network will provide an opportunity to assess the noise level distribution of traffic flows in Lviv city. It will help to determine the problem places and propose methods of combating traffic noise.

Short-term traffic prediction based on time series decomposition

Traffic flow decomposition is an alternative method to explore the composition of traffic flow and improve prediction accuracy. However, most of them suffer from the inability to fully utilize the character of traffic data. This paper presents a novel framework for traffic flow decomposition and modeling named Time Series Decomposition (TSD). The traffic flow is adaptively decomposed into periodic component, residual component and volatile component which are modeled respectively. Empirical Mode Decomposition (EMD) is applied to extract the intrinsic mode functions (IMFs) of traffic flow, the periodic patterns are intuitively presented via Hilbert transform in terms of frequencies. Then the periodic component can be described as a Fourier series based on obtained frequencies. Meanwhile, the residual component is presented by IMF with the lowest frequency. The remaining part is the volatile component modeled by supervised learning. The proposed hybrid model is evaluated on the real-world dataset and compared with classical baseline models. The results demonstrate that TSD can unearth the underlying periodic patterns and provide an explicable composition of the traffic flow. Furthermore, the volatile component ensures the accuracy of single-step prediction while periodic and residual components show promising abilities in improving the multi-step prediction accuracy of short-term traffic flow.

Determination of passenger car noise equivalent for mid-sized cities in India

The heterogeneity in traffic flow composition increases the complexity of road traffic noise analysis for mid-sized in India. This study aims to determine a passenger car noise equivalent (PCNE) with respect to the average traffic stream speed that represents the number of a particular vehicle category with reference to an identified vehicle based on their noise emission characteristics. In the present study, vehicles are classified as bus, truck, light commercial vehicles (minibus, minitruck), three-wheelers (vikram-rickshaw), two-wheelers (bike/scooter), car, e-rickshaw and auto-rickshaw, and tractor-trailer. Car is taken as a reference vehicle for estimation of PCNE in our study due to its high percentage in traffic stream. Data has been collected on both bituminous and concrete pavement in Kanpur city, India, to analyze the differential effect of pavement on the noise level. As per this study, tractors-trailers, trucks, three-wheelers, and buses had a higher PCNE value, while two-wheelers and cars had almost similar PCNE value. A comparative analysis of PCNE value at concrete pavement is also conducted by considering car running on the bituminous pavement as reference vehicle. The study suggests to employ PCNE value in traffic noise analysis as it converts the divergent traffic volume in terms of the car.

Study of the ways to increase the urban street and road network capacity

During the existing situation assessment on the urban road network and intersections design, it is necessary to establish the traffic capacity value of streets and its elements. When forecasting the capacity value it is necessary to turn traffic flow presented by different vehicles to uniformity expressed in the equivalent number of passenger cars by using passenger car equivalent coefficients (PCE). PCE currently used in the Russian Federation are formed on the capacity studies of the street-road network, carried out in the 70s-80s of the last century on rural roads, where the traffic flow was mostly presented by heavy vehicles. Nowadays the major percentage of traffic flow is presented by passenger cars. At the same time, the dynamic performances of trucks and buses have changed significantly. In this regard, the question of clarifying the traffic flow composition and revising the passenger car equivalent coefficients becomes urgent. High level of streets congestion and intersections with a small heavy vehicle percentage in the traffic flow is most often observed in large cities. The studies were carried out on the the multi-lane highway in Moscow in the sections free from the intersections and junctions influence. The purpose of the study was to clarify the traffic flow composition and determine the passenger car equivalent coefficients in modern traffic conditions.

Traffic intensity calculation criteria for freight vehicles

To choose the road pavement, it is necessary to determine the traffic intensity and composition of the traffic flow on highways. The existing methods are used depending on the number of axles or carrying capacity of trucks. The purpose of this study is to compare the methods for determining the traffic intensity of vehicles and analyze the values of the minimum total modulus of elasticity. The article presents the results of calculation of the modulus of elasticity based on the traffic flow, the number of axles and carrying capacity of the vehicle. As part of the analysis, tables were compiled, the total estimated number of applications of the design load to a surface point was determined, and the minimum total modulus of elasticity of the road structure was calculated. The result of the research is recommendations for choosing a method for recording traffic intensity depending on the road category and traffic flow composition.

Assessment of possibility of "Park and ride" system in Kharkiv, Ukraine

The article considers the possibility of the "Park and ride" system in Kharkiv (Ukraine). Paper is based on studying the demand for parking services for incoming drivers to urban area. Analysis of methods of «park and ride» technologies was carried out. The nodes of the transport network that are suitable for the arrangement of «park and ride» lots in Kharkiv was determined. Based on the results of this review, 7 potential places were identified for the placement. In the listed nodes, full-scale examinations of the intensity and traffic flow composition were done. The processing of the survey results evaluated the intensity of traffic flow of privet cars that enter the urban area during the morning rush hour. Results of the transport demand research in the possible «park and ride» lots according to the travel distance have shown: the largest number of cars (30%) travelled at a distance of 5 to 8 km; 21% - generates a road traffic in the ranges of 2 ... 5 km and 8 ... 12 km; 11% - up to 2 km and 12% - 12 ... 16 km. The obtained results revealed generation of distribution of private cars trips based on the distance from the nodes of the possible location of «park and ride» parking lots is insufficient to determine the potential demand for parking data. The obtained data can be used in the development of urban master plans, projects of transport infrastructure facilities.

Analysis of saturation flow on isolated lanes of controlled intersections with significant traffic intensity

The methods and results of the investigation of intervals between vehicles during queue dissipation before controlled intersections with the further determination of saturation flow are reviewed in this paper. Having reviewed existing methods of determining the saturation in traffic flows, those are determined which provide the most certain results in conditions of intensive movement and take into account quite a large number of impact factors. Such methods are based on experimental measurement of intervals between vehicles during their passage through the stop-line in different directions of the controlled intersection. For the completeness of the analysis of such intervals, such factors are considered additionally as traffic composition and use of lanes by directions. Objects of the research are controlled intersections on approaches to which the slope is absent, there is no pedestrian and cyclist movement during the performance of turn, and conflicting traffic flows and also public transport stops in the zone of the intersection. The transitional research result is the determination of the number of vehicles that pass the stop-line during the permissive signal and time intervals between them, and the final result is the oncoming of saturation period on the lanes of straight and turns movement depending on traffic flow composition.

Selection of a traffic management scheme at an intersection taking into consideration the traffic flow composition

Traffic flows in large cities have a non-uniformed character of origin and changes. The main parameters are often sensitive to the changes in the environmental conditions, specifically, the time of the day, season, etc. The magnitudes that characterize traffic flows have a stochastic nature and therefore they are difficult to predict. According to this, indicators such as intensity, density and traffic speed over time and space are uneven. Taking this into consideration, during the development of traffic management schemes, there arises a necessity to take into consideration additional factors which are of probabilistic nature. This approach provides more opportunities in the traffic management process and makes it possible to use appropriate ways to choose traffic management methods in certain cases. This process involves detailed studies of traffic indicators. The approaches and methods for studying the main indicators of traffic flows were given. They include both field methods and simulation, which involves accounting of mathematical and physical patterns of traffic flows. It also makes it possible to predict the situation when choosing a traffic management scheme with the use of computer equipment. The results of the studies, which were conducted according to the described methods, were analyzed. These results indicate a close relationship between the relative traffic composition for the types of vehicles and the indicators of queuing and delays within the intersections. According to the results, mathematical dependences characterizing this relationship were obtained. It was established that the choice of a road traffic scheme at intersections should be made taking into consideration the traffic flow composition, as each regulation type is effective for a particular case

Road Traffic Noise Levels at Different Types of Residential Areas in Nibong Tebal, Penang

Traffic vehicles on the road networks during their movement create noise that has greater impact on environment. The sources, the receivers and the place of transition, where the sound wave propagates, are the three vital parameters for the field of noise acoustics. For this research, the aim of this study is to assess traffic noise levels between different types of residential areas in Nibong Tebal, Penang. The study is carried out in order to achieve the following three main objectives, which are to assess the level of traffic noise at selected residential areas, to characterize the traffic flow composition nearby study areas, and to compare noise levels between low density and terraced house residential areas. The noise levels measurements were carried out periodically in the morning (from 0700 to 1100), evening (from 1600 to 1900), and at night (from 2200 to 2300) for 15 minutes using a sound level meter. The traffic characteristics were measured simultaneously during noise levels measurements. The highest equivalent continuous noise levelsfor the low density residential areas was at Kampung Batu 2 in the evening with 65.9 dB(A), while for the medium density residential areas, Taman Sri Acheh contributed 68.60 dB(A) during the morning. The lowest equivalent continuous noise levelswere obtained at Kampung Simpang Tiga in the morning that contributed 54.9 dB(A) for low density residential areas. However, the minimum equivalent continuous noise levelsobtained for the medium density residential areas was at Taman Ilmu Indah in the morning with 63.10 dB(A). The results obtained, clearly show that the equivalent continuous noise level for all study sites exceeded the maximum permissible sound level for medium density areas during daytime (from 7.00 am to 10.00 pm), which is 55 dB(A), while at night time (from 10.00 pm to 7.00 am) is 45 dB(A), and for low density residential areas during daytime (from 7.00 am to 10.00 pm) is 55 dB(A), while at night time (from 10.00 pm to 7.00 am) is 45 dB(A), respectively. These values are based on the guidelines for environmental noise limits and control by the Department of Environment, Malaysia.

Modeling of traffic-light signalization depending on the quality of traffic flow in the city

The high level of motorization typical for many cities gives background to the emergence of congestion situations, which largely reduces the transporting access to and unimpeded movement. To resolve occurring traffic problems are used for various kinds of activities that subunits are radical and conservative. For existing cities, quite often used the second type of events that do not require significant capital investments compared to the first one of these activities is improvement of traffic lights regulation, to reduce delays to vehicles by changing the input parameters required in the calculation. In this work the authors is proposed to model the traffic signalization traffic fl ow based on its qualitative composition. The growth of car ownership contributes to the change in the qualitative composition of traffic flow, that is not to be taken in determining the modes of traffic lights regulation. The authors performed a study of urban traffic, the results of which allowed to determine the values of the distributions of vehicles in the stream with regard to its composition, based on the extension of the main rolling stock type - passenger car. Based on the obtained distributions, a mathematical analysis for determining the influence of each considered class and refined method of calculation of the traffic signalization. The purpose of the proposed assessment to the development of a methodology for calculating the experimental computer simulation, the comparative analysis of the obtained data and the main conclusions of the study.

Нормирование основных транспортно-эксплуатационных качеств зимних лесовозных автомобильных дорог

The main material for the construction of the coatings of the winter forest roads is snow. The creation of this snow and ice durable material of the structural layers of pavement associated with a number of features. The main parameter that will define the structural strength of the pavement to be the hardness of the snow. In the operation of the winter timber-carrying roads this option almost never defined. We have conducted studies on the formation of a layer of compacted coating on the roadway depending on the amount of precipitation. The evaluation of the degree of influence of the density of falling snow on the magnitude of the compacted layer. When studying the degree of influence of precipitation was analyzed climatic conditions that operated hauling winter roads. It has been shown that the density of snow in the compacted layer affects the intensity of movement of trains, composition of traffic flow, the humidity of the snow and air and snow temperature. The density of the layer of the same influences and the evaporation of snow. Based on the experimental data were obtained the coefficients of evaporation of snow for the entire winter for the conditions of the Ural region. Based on these data, the calculated values of the possible maximum thickness of compacted layer at various speeds of movement of logging trucks and the different density of freshly fallen snow. The dependencies of the density layer of snow monthly. Found that to find the value of the thickness of the compacted layer to the end of the winter period, it is necessary to take into account the wear and evaporation of snow in the next months. This was carried out to estimate the depth gauge on a Packed snow surface. The recommended values for the maximum depth gauge on the surface for various road-climatic sub-zones. Set values of a compacted snow layer on the roadway by the end of the winter period for winter timber transportation trunk roads for winter logging winter logging mustache and branches.

Analysis of the distribution of the number of applications of the estimated load on the Federal roads during the year

The article is devoted to the statistical processing of traffic intensity and composition of traffic flow obtained from the points of automated traffic intensity accounting for 2010-2018 in order to determine the distribution of the number of applications of the calculated load by months. The main source of information for statistical processing was the results of traffic accounting on highways M-1 «Belarus», a-107 MMK Mozhaisk-Volokolamsk highway, M-3 «Ukraine», M-4 «don», M-4 «don». The correct determination of the traffic intensity and composition of the traffic flow is an important task that allows you to make adequate decisions at the design stage of roads, namely to choose a road structure that can operate under load from the actual traffic flow for the entire service life. The authors calculated the total number of applications of the calculated load to the point on the surface of the coating, using the coefficients of reduction of vehicles to the calculated load of 115 kN. After calculating the total number of applications, the resulting value was divided by the number of days in the month in question. According to the data obtained, the total total number of applications of the calculated load at all points of accounting, by month, was found. The minimum values of the number of load applications are observed in winter (January, February, March), when the situation on the road deteriorates due to weather conditions. The values range from 4.75 % to 8 % for roads M-1 «Belarus», M-3 «Ukraine», M-4 «Don», M-4 «Don». The maximum values of the number of load applications observed in the warmer months (July, August, September, October), due to the fact that there are favorable weather conditions for recreation and the most active agricultural industry. The values range from 7.6 % to 11.3 % for the roads M-1 «Belarus», M-3 «Ukraine», M-4 «Don», M-4 «Don».

A Methodological Framework to Rank Energy Efficiency of Cities

Out of 17 sustainable development goals established by United Nations, the goal of sustainable cities and communities achievement can be addressed by having more energy saving cities. In this context this study will be useful in identifying sustainable cities in the evaluation of goal achievement as one indicator to measure sustainable cities. The objective of this study is to propose a methodology that would enable to rank energy efficient cities and to establish their rank priorities. Energy efficiency may be the cheapest, most abundant, and most underutilized resource for local economic and community development.In today’s context motorized transportation is highly being used, which resulted in more energy waste and pollution. Walking receives a considerable interest as non polluting transportation mode which results in energy saving as opposed to motorized traffic. We can have more energy saving cities by reducing the motor traffic and promoting more pedestrian friendly cities. In this context, measure of “walkability” has been used. This research attempts to identify a ranking system of cities to base on their energy efficiency in terms of walkability with the identified indicators.These indicators included daily traffic flow composition, Public transport network, pedestrian movements and an evaluation of existing pedestrian facilities within the city limits. On the basis of the surveys performed, the significance of indicators was determined.Since this being an initial attempt in ranking energy efficient cities in terms of walkability, researches can further develop this methodological framework and fine tune it towards an all inclusive ranking system of energy efficient cities. Keywords: Sutainable cities, Motorized transportation, Walkability, Pedestrian, Indicators