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Number of results: 68
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Abstract

Traffic related noise is currently considered as an environmental pollution. Paper presents results of multidirectional study attempting to serve urban traffic without the need to erect noise barriers interfering urban space. Initial concept of the road expansion included construction of 1000 m of noise barriers dividing city space. Improvement in the acoustic conditions after construction completion is possible due to the applied noise protection measures: vehicle speed limit, smooth of traffic flow, use of road pavement of reduced noise emission and the technical improvement of the tramway.

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Authors and Affiliations

K.J. Kowalski
A.J. Brzeziński
J.B. Król
P. Radziszewski
Ł. Szymański
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Abstract

The author investigated traffic flow quality on a new 2+1 long road bypass with an exceptionally high share of heavy vehicles in order to assess rational limits of heavy vehicle shares in traffic flow, dependent on the length of the 2+1 road and the number of passing segments in each direction. This paper presents the results of traffic flow quality analyses through the use of empirical and simulation methods for a single 2+1 road segment with additional passing lanes, as well as for the study of the entire section of the bypass – 2+1 road. Variables include analysis of travel speed distribution, platoon traffic, and amount of passing maneuvers. Results show that large passing demands lead to very high speeds (over 100 km/h) on segments with additional passing lanes. The conclusions include remarks related to the use and operation of 2+1 cross-sections with high shares of heavy vehicles.

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Authors and Affiliations

M. Kieć
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Abstract

One of the basic parameters which describes road traffic is Annual Average Daily Traffic (AADT). Its accurate determination is possible only on the basis of data from the continuous measurement of traffic. However, such data for most road sections is unavailable, so AADT must be determined on the basis of short periods of random measurements. This article presents different methods of estimating AADT on the basis of daily traffic (VOL), and includes the traditional Factor Approach, developed Regression Models and Artificial Neural Network models. As explanatory variables, quantitative variables (VOL and the share of heavy vehicles) as well as qualitative variables (day of the week, month, level of AADT, the cross-section, road class, nature of the area, spatial linking, region of Poland and the nature of traffic patterns) were used. Based on comparisons of the presented methods, the Factor Approach was identified as the most useful.

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Authors and Affiliations

M. Spławińska
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Abstract

The article presents a new approach to building a passenger rail traffic generation model. It uses data on the number of passengers at stations and railway stops obtained from the databases of operators on the rail transport market through the Office of Rail Transport – market regulator – combined with data on the model of the area around the station built based on population, number of beds, individual motorization and gross domestic product (GDP). This enabled analyzing the potential of railway traffic generation at a very detailed level. The article presents a methodology for building a passenger rail traffic generation model and verification of this model based on limited variables describing railway stations and stops as well as traffic zones and available statistical data. The model takes into account three segments of the railway market: regional, interregional and inter-agglomeration transport. The results of these analyzes can be used to increase the accuracy and the reliability of rail traffic models used in the analysis of transport networks.
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Authors and Affiliations

Andrzej Brzeziński
1
Andrzej Waltz
2
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
  2. independent consultant
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Abstract

In the paper, the BTS (Background Traffic Simulator) tool is proposed to capture network traffic and then reproduce it in a simulations using the ns-3 simulator extension module. This new method of generating background traffic allows for repetitive testing of simulation scenarios under real network conditions. The authors described the differences between the previously available methods and the proposed solution. The operation of all the most important elements of the proposed tool has been described. The influence of the generated background traffic on the simulation scenario was presented as well as the results of the operation.
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Authors and Affiliations

Szymon Stryczek
1
Mikołaj Gwiazdowicz
1
Marek Natkaniec
1

  1. Faculty of Computer Science, Electronics and Telecommunications, Institute of Telecommunications, AGH University of Science and Technology, Poland
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Abstract

In this paper, impact of changes in parameters of offered traffic on the accuracy of determining the parameters of overflow traffic in hierarchical systems with multi-service traffic was presented. Pascal type traffic streams were offered to the considered systems. The study investigated the impact of changes in the number of sources, intensity of traffic offered by individual classes, as well as changes in the traffic offered by a single free source. The presented results are based on determined relative errors of the values of overflow traffic obtained in simulations and on the basis of calculations.

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Authors and Affiliations

Marian Głąbowski
Damian Kmiecik
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Abstract

The article introduces a novel Internet diagnosis utility - an open source IP packet snifferwhich captures TCP and UDP packets sent and received by a single Linux process only. Preliminary evaluation results are presented. The utility can be applied in the field of IP traffic classification.

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Authors and Affiliations

Paweł Foremski
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Abstract

Traffic classification is an important tool for network management. It reveals the source of observed network traffic and has many potential applications e.g. in Quality of Service, network security and traffic visualization. In the last decade, traffic classification evolved quickly due to the raise of peer-to-peer traffic. Nowadays, researchers still find new methods in order to withstand the rapid changes of the Internet. In this paper, we review 13 publications on traffic classification and related topics that were published during 2009-2012. We show diversity in recent algorithms and we highlight possible directions for the future research on traffic classification: relevance of multi-level classification, importance of experimental validation, and the need for common traffic datasets.
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Authors and Affiliations

Paweł Foremski
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Abstract

The paper shows a study on the relationship between noise measures and sound quality (SQ) features that

are related to annoyance caused by the traffic noise. First, a methodology to perform analyses related to

the traffic noise annoyance is described including references to parameters of the assessment of road noise

sources. Next, the measurement setup, location and results are presented along with the derived sound quality

features. Then, statistical analyses are performed to compare the measurement results and sound quality

features. The included conclusions are focused on showing that the obtained loudness values, regardless of

the used system, are similar in a statistical sense. Contrarily, sharpness, roughness and fluctuation strength

values differ for the tools employed.

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Authors and Affiliations

Waldemar Paszkowski
Józef Kotus
Tomasz Poremski
Bożena Kostek
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Abstract

In recent years adverse processes of suburbanization have been observed in cities. It has become a serious challenge for urban and transport planners, as it influences largely the quality of space, the quality of life, and the cost of running the city. This paper is dedicated to travel models in areas serviced by a railway system, and is based on a real-life survey example of the Błonie community, a district belonging to the Warsaw metropolitan area. Research carried out in 2014 focused on combined travels behaviors recorded using GPS locators as well as quantitative research (volumes of users across various transport systems).

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Authors and Affiliations

A. Brzeziński
K. Jesionkiewicz-Niedzińska
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Abstract

The aim of the article was to determine the course of changes the urban space under the influence of tourism, on the example of selected areas in Cracow. A literature study, statistical data and field studies were used to explain the relationship between the growth of tourist movement and the development of the tourist space of this city. The impact of tourism on changes in public and private space use within Matejki Square and Pawia Street, in the neighbourhood of the historical zone (Old Town) and in the New Square at Kazimierz, was analysed. The conducted analysis showed three functional changes of the studied areas under the influence of the rapid tourist movement. They were transformed from residential-service to service-residential related to service of tourists (hotels, gastronomy, trade, entertainment). The urban space has been enriched with elements that increasing the tourist attractiveness of Cracow compared with other cities, for example, concerning spending free time (pubs, cafés, restaurants), and the new accommodation base near the city-centre. A lack of a zoning plan and development vision causes the helplessness of the local authorities in managing the tourist infrastructure development, which is reflected at the Kazimierz New Square.

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Authors and Affiliations

Mariola Tracz
Marcin Semczuk
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Abstract

At the beginning of the COVID-19 pandemic the government of Spain decreed the State of Alarm to confine the entire population at their homes, except for essential services. Therefore, the central objective of this study is to evaluate the implication of this situation for the environmental noise existing in the city of Huelva (Spain). This study demonstrates that during the state of alarm an average daily reduction of 3.4 dBA was noted, and in the central moments of the day these reductions reached up to 4.4 dBA, while from 10:00 to 12:00 pm the reduction was around 6.5 dBA. Nevertheless, there were two moments of day: 3:00 am (garbage collection, street cleaning and container disinfection), and 8:00 pm (daily applause for health professionals), when the noise during the pandemic was higher than before it. It is further shown that globally, the loudest events only decreased by about 3 dBA, while the global background noise decreased by 10 dBA during the alarm state. Regarding road traffic noise, it is verified that in addition to being reduced by about 4 dBA, traffic represents 6.7% of noisy events during the alarm state, while before it represented 13%.
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Authors and Affiliations

Juan Carlos Fortes
1
Rafael Sánchez-Sánchez
1
Juan Pedro Bolívar
2

  1. School of Engineering, University of Huelva, Huelva, Spain
  2. Faculty of Experimental Sciences, University of Huelva, Huelva, Spain
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Abstract

Knowledge about future traffic in backbone optical networks may greatly improve a range of tasks that Communications Service Providers (CSPs) have to face. This work proposes a procedure for long-term traffic forecasting in optical networks. We formulate a long-terT traffic forecasting problem as an ordinal classification task. Due to the optical networks’ (and other network technologies’) characteristics, traffic forecasting has been realized by predicting future traffic levels rather than the exact traffic volume. We examine different machine learning (ML) algorithms and compare them with time series algorithms methods. To evaluate the developed ML models, we use a quality metric, which considers the network resource usage. Datasets used during research are based on real traffic patterns presented by Internet Exchange Point in Seattle. Our study shows that ML algorithms employed for long-term traffic forecasting problem obtain high values of quality metrics. Additionally, the final choice of the ML algorithm for the forecasting task should depend on CSPs expectations.
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Authors and Affiliations

Krzysztof Walkowiak
1
Daniel Szostak
1
Adam Włodarczyk
1
Andrzej Kasprzak
1

  1. Wroclaw University of Science and Technology, Poland
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Abstract

This article discusses the traffic types typically used in industrial networks. The authors propose a number of methods of generating traffic that can be used in modeling traffic sources in the networks under consideration. The proposed traffic model have been developed on the basis of the ON/OFF model. The proposed solutions can be applied to model typical traffic types that are used in industrial systems, such as Time-Triggered (TT) traffic, Audio-Video Bridging (AVB) traffic or Best Effort traffic. The article discusses four traffic models with modifications and shows how the proposed models can be used in modeling different traffic types used in industrial networks.

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Authors and Affiliations

M. Głąbowski
S. Hanczewski
M. Stasiak
M. Weissenberg
P. Zwierzykowski
V. Bai
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Abstract

The existing traffic noise prediction models in road intersections relate mainly to the typical solutions of intersection geometry and traffic organisation. There are no models for large and more complex intersections such as signalised roundabouts. This paper presents the results of studies on the development of a traffic noise prediction model for this type of intersection. The model was developed using a multiple regression method based on the results of field measurements of traffic parameters and noise levels in the vicinity of signalised roundabouts in Poland. The obtained model consists of two groups of variables affecting noise levels at the intersection. The first group determines in detail the influence of traffic and geometry of the closest entry. The second group shows the influence of more distant noise sources (traffic at the three remaining entries of the intersection) and the influence of the dimensions of the entire intersection. The developed model was verified through additional field measurements, as well as compared to the results of two methods of traffic noise prediction: the French ‘NMPB-Routes-2008’ and the German ‘RLS-90’. The obtained results confirmed a higher accuracy of calculations performed using the developed model in the range of: −1.2 dB ÷ +1.0 dB, while the ‘NMPB-Routes-2008’ and ‘RLS-90’ calculate precision were respectively: −2.8 dB ÷ +1.3 dB, and +0.8 dB ÷ +5.2 dB. Therefore, the developed model allows for a more accurate prediction of noise levels in the vicinity of signalised roundabouts in a flat terrain without buildings and noise barriers.

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Authors and Affiliations

M. Motylewicz
W. Gardziejczyk
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Abstract

The effectiveness of applied means of traffic noise protection can be determined through examining acoustic climate of the areas located near the communication routes. It allows to determine sound level in a specific area and determine the extent that its inhabitants are exposed to the effects of noise. The research and the analysis of the acoustic climate were carried out in the town of Podszosie, located in the vicinity of the S7 expressway. The aim of the research was: to determine the level of noise emitted by traffic on the S7 expressway, to determine the effectiveness of noise barriers installed in a given area, to determine the sound level in the vicinity of properties located in Podszosie, to determine whether the noise level in Podszosie is normal. The conducted research allowed the authors to determine the sound level prevailing in the study area, and to what extent its inhabitants are exposed to the effects of noise and how to prevent it. Showing the scale of the problem posed by noise from road transport. In addition to carrying out activities aimed at reducing its level, society should also be made aware of the harmful effects of its impact.
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Bibliography


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Authors and Affiliations

Zbigniew Łukasik
1
ORCID: ORCID
Aldona Kuśmińska-Fijałkowska
1
ORCID: ORCID
Jacek Kozyra
1
ORCID: ORCID
Sylwia Olszańska
2
ORCID: ORCID

  1. Faculty of Transport, Electrical Engineering and Computer Science, Kazimierz Pulaski University of Technology and Humanities in Radom, Radom, Poland
  2. Chair of Logistics and Process Engineering, University of Information Technology and Management in Rzeszow, Rzeszow, Poland
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Abstract

A microsimulation approach was carried out in this paper to evaluate the safety performance of turbo roundabouts in which the "CAVs" of connected autonomous vehicles are mixed with the "CVs" of conventional vehicles the research aims to evaluate the advantages in terms of safety and performance of turbo roundabouts. The paper shall also lead to describe the methodological path followed to build VISSIM models of turbo roundabout changing O-D matrix as real case applications, to calibrate the simulation models, and to estimate the potential conflicts when the percentages of CAVs are introduced into the traffic mix. The results, in accordance with the existing bibliography, have shown that the safety levels and the parameters that determine an improvement in the service level in a turbo roundabouts are significantly influenced not only by the geometric characteristics, but also by the distribution of vehicular flows. Therefore, it follows that in absence of crash data including CAVs, the surrogate measures of safety must be considered a strong approach to evaluate the safety performance of a roundabout so far, any road entity.
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Authors and Affiliations

Alessandro Severino
1
Giuseppina Pappalardo
1
Salvatore Trubia
2

  1. Faculty of Engineering and Architecture Polytechnic School, University of Catania, Viale Santa Sofia, 64 Ed 3, 95123 - Catania, Italy
  2. Faculty of Engineering and Architecture, University of Enna Kore, Cittadella Universitaria Viale delle Olimpiadi, Enna, Italy
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Abstract

The wearing courses (top layers) of the streets in towns are usually of asphalt concrete, paving stones or cement concrete blocks type. They must provide good load capacity, high friction, comfortable and quiet ride. The problem of traffic noise reduction by use of proper road surfaces is not very often addressed in Poland. Due to legislation and technical progress during the last decades, a substantial reduction of the power unit noise emitted by cars and trucks has been achieved. It is observed that nowadays even at low speeds typical for urban driving the dominating noise comes from the tyres. The paper compares typical road surfaces that are used in towns from the point of view of their influence on the traffic noise.
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Authors and Affiliations

Władysław Gardziejczyk
Jerzy A. Ejsmont
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Abstract

In the paper, the simulation PROP5 program is used to predict the sound level in proximity of a road with defined surroundings. The simulation involves road geometry (number of lanes and their positions) and traffic structure (vehicle flow rates and their average speeds), with equivalent omnidirectional point sources representing vehicles. In Part I of the paper, the agreement between measurement and simulation results is tested to verify the accuracy degree of the applied models of a road, as a noise source and propagation throughout surrounding space. In Part II, using the pre-tested simulation program, the possibility of acoustic climate improvement has been analyzed.

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Authors and Affiliations

Elżbieta Walerian
Ryszard Janczur
Mieczysław Czechowicz
Yulija Smyrnova
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Abstract

n the paper, the simulation PROP5 program with the road model defined as a noise source and road surroundings model, is used to predict the efficiency of noise protecting means for the chosen building. The appropriate models of verified accuracy have been chosen by comparison of the simulation results with field measurements (Walerian et al., 2010). Here, using the pre-tested simulation program, the possibility of acoustic climate improvement has been analyzed in the ranges of practical variations of the input parameters. The road parameters: its geometry (number of lanes and their positions) and traffic structure over lanes (vehicle flow rates and their average speeds) have been taken under consideration as changeable parameters, that could be corrected to obtain acoustical climate improvement. Moreover, an acoustical screen designing has been considered. The screen efficiency has been evaluated under conditions defined by the input parameters of the road and its surroundings.

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Authors and Affiliations

Elżbieta Walerian
Ryszard Janczur
Mieczysław Czechowicz
Yulija Smyrnova
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Abstract

Noise measurements have been carried out at eleven different sites located in three prominent cities of the Tarai region of India to evaluate the effectiveness of vegetation belts in reducing traffic noise along the roadsides. Attenuation per doubling of distance has been computed for each site and excess attenuation at different 1/3 octave frequencies has been estimated. The average excess attenuation is found to be approximately 15 dB over the low frequencies (200 Hz to 500 Hz) and between 15 dB to 20 dB over the high frequencies (8 kHz to 12.5 kHz). Over the critical middle frequencies (1-4 kHz), the average excess attenuation (between 10-15 dB) though not as high, is still significant, with a number of sites showing an excess attenuation of 15 dB or more at 1 kHz. The results indicate that sufficiently dense vegetation belts along the roadsides may prove as effective noise barriers and significant attenuation may be achieved over the critical middle frequencies (1-4 kHz).
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Authors and Affiliations

Vikrant Tyagi
Krishan Kumar
V.K. Jain
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Abstract

The use of periodic structures as noise abatement devices has already been the object of considerable research seeking to understand its efficiency and see to what extent they can provide a functional solu- tion in mitigating noise from different sources. The specific case of sonic crystals consisting of different materials has received special attention in studying the influence of different variables on its acoustic performance. The present work seeks to contribute to a better understanding of the behavior of these structures by implementing an approach based on the numerical method of fundamental solutions (MFS) to model the acoustic behavior of two-dimensional sonic crystals. The MFS formulation proposed here is used to evaluate the performance of crystals composed of circular elements, studying the effect of varying dimen- sions and spacing of the crystal elements as well as their acoustic absorption in the sound attenuation provided by the global structure, in what concerns typical traffic noise sources, and establishing some broad indications for the use of those structures.
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Authors and Affiliations

Mário Martins
Luís Godinho
Luís Picado-Santos
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Abstract

Enhanced Traffic Management System (ETMS) stores all the information gathered by the Federal Aviation Administration (FAA) from aircraft flying in the US airspace. The data stored from each flight includes the 4D trajectory (latitude, longitude, altitude and timestamp), radar data and flight plan information. Unfortunately, there is a data quality problem in the vertical channel and the altitude component of the trajectories contains some isolated samples in which a wrong value was stored. Overall, the data is generally accurate and it was found that only 0.3% of the altitude values were incorrect, however the impact of these erroneous data in some analyses could be important, motivating the development of a filtering procedure. The approach developed for filtering ETMS altitude data includes some specific algorithms for problems found in this particular dataset, and a novel filter to correct isolated bad samples (named Despeckle filter). As a result, all altitude errors were eliminated in 99.7% of the flights affected by noise, while preserving the original values of the samples without bad data. The algorithm presented in this paper attains better results than standard filters such as the median filter, and it could be applied to any signal affected by noise in the form of spikes

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Authors and Affiliations

Rafael Palacios
R. John Hansman

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