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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Verkehrsökologische Schriftenreihe

12 April 2016 (has links)
Ziel der „Verkehrsökologischen Schriftenreihe“ ist es, die Forschungsergebnisse der Professur für Verkehrsökologie (TU Dresden) und ausgewählte studentische Arbeiten einer breiteren Öffentlichkeit zugänglich zu machen. Damit möchten wir einerseits die fachliche Diskussion zu Problemstellungen einer nachhaltigen Mobilitätsentwicklung und anderseits den offenen Zugang zu Wissen und Informationen unterstützen. Thematisch greift die Schriftenreihe dabei die folgenden Forschungsschwerpunkte der Professur auf: a) Nachhaltige Verkehrsentwicklung: Auswirkungen, Verfahren, Konsequenzen b) Klimaschutz, Energie und CO2 im Verkehr c) Luftreinhaltung & Lärm, Emissionsfaktoren und reale Fahrmuster d) Externe Kosten und Nutzen des Verkehrs, Kostenwahrheit und Internalisierung e) Rad- und Fußverkehr f) Umweltbildung, Monitoring und Evaluation g) Soziale Exklusion und Umweltgerechtigkeit im Verkehrsbereich
82

Vyhodnocování dopravního hluku a jeho modelování / Evaluation and modelling of Traffic Noise

Černoch, Adam January 2014 (has links)
The task of the master's thesis is introduction with the problems of traffic noise, focusing on noise from road traffic. There is a description what is the noise, how it is formed, its resources and what are the methods of measuring. The following are the various noise reduction measures such as noise barriers and low noise pavements. The main attention is devoted to the noise generated at the tire / road that is reduced by these pavements. The practical part describes the implemented measurements on individual sections at various locations in our country. The measurement was carried by slightly modified method CPX with reference tire directly at the vehicle. The main aim was to evaluate the measurement data, make comparison of different low-noise surfaces with each other and with the commonly used surfaces. Then quantification of the rate reduction of the noise emission for a given section and verification of input data for noise modeling. In conclusion, the obtained results are summarized and based on them were confirmed very good acoustic properties with the recommendation to continue with measurements in the future.
83

Verkehrsökologische Schriftenreihe

12 April 2016 (has links)
Ziel der „Verkehrsökologischen Schriftenreihe“ ist es, die Forschungsergebnisse der Professur für Verkehrsökologie (TU Dresden) und ausgewählte studentische Arbeiten einer breiteren Öffentlichkeit zugänglich zu machen. Damit möchten wir einerseits die fachliche Diskussion zu Problemstellungen einer nachhaltigen Mobilitätsentwicklung und anderseits den offenen Zugang zu Wissen und Informationen unterstützen. Thematisch greift die Schriftenreihe dabei die folgenden Forschungsschwerpunkte der Professur auf: a) Nachhaltige Verkehrsentwicklung: Auswirkungen, Verfahren, Konsequenzen b) Klimaschutz, Energie und CO2 im Verkehr c) Luftreinhaltung & Lärm, Emissionsfaktoren und reale Fahrmuster d) Externe Kosten und Nutzen des Verkehrs, Kostenwahrheit und Internalisierung e) Rad- und Fußverkehr f) Umweltbildung, Monitoring und Evaluation g) Soziale Exklusion und Umweltgerechtigkeit im Verkehrsbereich
84

Flygtrafikbuller i hemmiljö : En enkätundersökning om besvärsupplevelser och hälsa i relation till flygbuller för boende kring Linköping City Airport / Air Traffic Noise in the Home Environment : A survey of disturbances and self-reported health in relation to air traffic noise for residents around Linköping city airport

Lindeler, Sara January 2019 (has links)
Introduktion: Buller definieras som oönskat ljud. Uppfattningen av ett oönskat ljud är mycket individuellt. Det som anses vara oljud för en person, kan upplevas som icke-oljud för en annan person. Buller anses dock generellt som störande ljud och är vanligtvis något som varje individ stöter på under sin vardag som exempelvis på arbetsplatsen, skolan, eller i hemmet. Buller anses vara den miljöstörning som berör flest människor i Sverige. Det är ett växande problem och flygtrafik anses vara en av de mest genomgripande utomhusljudkällorna. Bullerproblem som är förknippade med flygtrafik är koncentrerade i områden nära flygplatser, vilket kan påverka flera tusentals boendes hälsa. Flygtrafikbuller har länge varit ett folkhälsoproblem och många människor som är bosatta i närheten av en flygplats har utvecklat ett antal negativa hälsoeffekter av flygtrafikbuller Syfte: Att undersöka hur boende som är bosatta nära flygplatsen Linköping City Airport upplever och påverkas av flygtrafikbuller.  Metod: Studien har utförts som en enkätundersökning med en kvantitativ tvärsnittsdesign. Webbenkäten som har använts som mätinstrument har konstruerats för att besvara syftet. 292 vuxna individer (>18år), varav 158 män och 133 kvinnor, deltog i studien. Insamlad statistiska data har bearbetats och analyserats i SPSS. För att kunna besvara syftet har följande statistiska tester använts: chi2-test, spearmans-korrelationsanalys och logistisk regressionsanalys.   Resultat och konklusion: Boende som är bosatta i Tannefors visade överlag positiva upplevelser till flygtrafiken och var positivt inställda till flygplatsen. De boende som upplevde störningar minst varje vecka vissa delar av året upplevde att flygtrafikbuller medför svårigheter att utföra olika aktiviteter. Kvinnor i den yngsta åldersgruppen upplevde flygtrafikbuller som mer störande jämfört med män. Män hade en mer negativ inställning till flygplatsen jämfört med kvinnor. Boende som rapporterade sämre hälsotillstånd, sömnproblem och användande av öronproppar eller något annat hörselskydd för att kunna sova bättre, sämre sömnkvalitet, trötthet, obehagskänslor, ledsenhet och nedstämdhet, osällskaplighet och att man föredrar att vara ifred, irritation och vresighet, stress, lock eller tinnitus i öronen meddelade också ett större besvär för flygtrafikbuller. / Introduction: Aircraft noise is an example of unwanted sound. The perception of unwanted sound is very individual. What is considered noise by one person may be perceived as non-noise by someone else. However, noise is generally regarded as disturbing noise and is usually something that each individual encounters in their daily life, such as in the workplace, at school, or at home. Noise is considered to be the form of environmental disruption that affects the most people in Sweden. It is a growing problem, and air traffic is considered to be one of the most pervasive outdoor sound sources. Noise problems associated with air traffic are concentrated in areas close to airports, which can affect the health of thousands of residents. Air traffic noise has long been a public health problem, and many people living near an airport have developed a number of negative health effects due to air traffic noise. Purpose: To study how residents living near Linköping City Airport experience and are affected by air traffic noise.   Method: The study has been conducted as a questionnaire survey with a quantitative crosssectional design. The online survey that has been used as a measuring instrument has been designed to answer the purpose. 292 adult subjects (> 18 years), including 158 men and 133 women, participated in the study. Collected statistical data has been processed and analysed in SPSS. In order to answer the purpose, the following statistical tests have been used: chi2 test, Spearman’s correlation analysis and logistic regression analysis. Results and conclusion: Residents living in Tannefors generally had positive experiences from air traffic and were positive towards the airport. The residents who experienced disturbances at least every week during certain parts of the year felt that air traffic noise caused difficulties performing various activities. Women in the youngest age group experienced air traffic noise as more disturbing compared to men. Men had fewer negative attitudes towards the airport compared to women. Residents who reported poorer health conditions, sleep problems and the use of earplugs or other hearing protectors to be able to sleep better, poorer sleep quality, fatigue, discomfort, sadness and depressed mood, low morale, a desire to be left alone, irritation and grief, stress, clogged ear or tinnitus also started that air traffic noise was a major inconvenience.
85

Detection and Classification of Sparse Traffic Noise Events / Detektering och klassificering av bullerhändelser från gles trafik

Golshani, Kevin, Ekberg, Elias January 2023 (has links)
Noise pollution is a big health hazard for people living in urban areas, and its effects on humans is a growing field of research. One of the major contributors to urban noise pollution is the noise generated by traffic. Noise simulations can be made in order to build noise maps used for noise management action plans, but in order to test their accuracy real measurements needs to be done, in this case in the form of noise measurements taken adjacent to a road. The aim of this project is to test machine learning based methods in order to develop a robust way of detecting and classifying vehicle noise in sparse traffic conditions. The primary focus is to detect traffic noise events, and the secondary focus is to classify what kind of vehicle is producing the noise. The data used in this project comes from sensors installed on a testbed at a street in southern Stockholm. The sensors include a microphone that is continuously measuring the local noise environment, a radar that detects each time a vehicle is passing by, and a camera that also detects a vehicle by capturing its license plate. Only sparse traffic noises are considered for this thesis, as such the audio recordings used are those where the radar has only detected one vehicle in a 40 second window. This makes the data gathered weakly labeled. The resulting detection method is a two-step process: First, the unsupervised learning method k-means is implemented for the generation of strong labels. Second, the supervised learning method random forest or support vector machine uses the strong labels in order to classify audio features. The detection system of sparse traffic noise achieved satisfactory results. However, the unsupervised vehicle classification method produced inadequate results and the clustering could not differentiate different vehicle classes based on the noise data. / Buller är en stor hälsorisk för människor som bor i stadsområden, och dess effekter på människor är ett växande forskningsfält. En av de största bidragen till stadsbuller är oljud som genereras av trafiken. Man kan utföra simuleringar i syfte att skapa bullerkartor som kan användas till planer för att minska dessa ljud. För att testa deras noggrannhet måste verkliga mätningar tas, i detta fall i formen av ljudmätningar tagna intill en väg. Syftet med detta projekt är att testa maskininlärningsmetoder för att utveckla ett robust sätt att detektera och klassificera fordonsljud i glesa trafikförhållanden. Primärt fokus ligger på att detektera bullerhändelser från trafiken, och sekundärt fokus är att försöka klassificera vilken typ av fordon som producerade ljudet. Datan som används i detta projekt kommer från sensorer installerade på en testbädd på en gata i södra Stockholm. Sensorerna inkluderar en mikrofon som kontinuerligt mäter den lokala ljudmiljön, en radar som detekterar varje gång ett fordon passerar, och en kamera som också detekterar ett fordon genom att ta bild på dess registreringsskylt. Endast ljud från gles trafik kommer att beaktas och användas i detta arbete, och därför används bara de ljudinspelningar där radarn har upptäckt ett enskilt fordon under ett 40 sekunders intervall. Detta gör att den insamlade datan har svaga etiketter. Den resulterande detekteringsmetoden är en tvåstegsprocess: För det första används den oövervakade inlärningsmetoden k-means för att generera starka etiketter. För det andra används de starka etiketterna av den övervakade inlärningsmetoden slumpmässig beslutsskog eller stödvektormaskin i syfte att klassificera ljudegenskaper. Detekteringssystemet av glest trafikljud uppnådde tillfredsställande resultat. Däremot producerade den oövervakade klassificeringsmetoden för fordonsljud otillräckliga resultat, och klustringen kunde inte urskilja mellan olika fordonsklasser baserat på ljuddatan.
86

Caractérisation physique et perceptive de différentes compositions de trafic routier urbain pour la détermination d'indicateurs de gêne en situation de mono-exposition et de multi-exposition / Physical and perceptual characterization of different compositions of urban road traffic for the determination of indicators of annoyance via single and combined exposure

Gille, Laure-Anne 01 July 2016 (has links)
Le bruit de la circulation routière, et en particulier le bruit des deux-roues motorisés, constituent une importante source de gêne sonore. Afin d’estimer l’exposition sonore dans les villes de plus 100 000 habitants, la directive européenne 2002/49/CE impose la réalisation de cartes de bruit stratégiques, basées sur l’indice Lden. Cet indice est également utilisé dans des relations exposition-réponse, afin de prédire les pourcentages de personnes gênées, notamment par le bruit du trafic routier. En couplant les cartes de bruit stratégiques et ces relations exposition-réponse, des cartes de gêne pourraient être établies. Toutefois, la pertinence de cet indice pour prédire la gêne due au bruit en milieu urbain est souvent remise en cause, car de nombreux facteurs acoustiques influents (e.g. les caractéristiques spectrales et temporelles) ne sont pas pris en compte par cet indice. Cette thèse vise à améliorer la caractérisation de la gêne due au bruit de trafic routier urbain en considérant différentes compositions de trafic et la présence des deux-roues motorisés. Dans ce but, des expériences sont menées en conditions contrôlées. Une première étude a porté sur l’influence de plusieurs facteurs acoustiques relatifs aux périodes de calme et aux bruits de passage de véhicules sur la gêne due au bruit de trafic routier urbain. Cette étude a conclu à l’influence de la présence de périodes de calme et du nombre de véhicules au sein du trafic routier urbain et à l’absence d’influence de l’ordre des véhicules routiers, de la position et de la durée des périodes de calme. Ces résultats ont été utilisés afin de mener la caractérisation physique et perceptive de différentes compositions de trafic routier urbain. La régression multi-niveau a été utilisée pour calculer la gêne, en considérant 1) des facteurs acoustiques influents à l’aide de combinaisons pertinentes d’indices et 2) un facteur non acoustique : la sensibilité au bruit. Dans les villes, le bruit routier est souvent entendu en situation de multi-exposition avec d’autres bruits. Dans le cadre de ces travaux de thèse, les situations de multi-exposition aux bruits routier et d’avion ont été étudiées. Pour cela, un travail semblable à celui mené pour le bruit de trafic routier urbain a été mené pour le bruit d’avion conduisant également à des combinaisons pertinentes d’indices. En vue de caractériser les gênes dues aux bruits de trafic routier et d’avion pour des situations de multi-exposition sonore, les données des précédentes expériences ainsi que celles d’une expérience conduite en situation de multi-exposition à ces bruits combinés ont été utilisées au travers d’une régression multi-niveau adaptée, comme cela a pu être mené dans la littérature. La régression multi-niveau a ainsi permis la proposition de modèles de gêne pour chaque source de bruit. Puis, la gêne totale due à des situations de multi-exposition à ces bruits a été étudiée, afin de mettre en évidence les phénomènes perceptifs mis en jeu. Des modèles de gêne totale ont été proposés, en utilisant les modèles de gêne due à chaque source. Enfin, les modèles de gêne obtenus pour chaque source et les modèles de gêne totale ont été confrontés aux données d’une enquête socio-acoustique. A cet effet, une méthodologie a été proposée afin d’estimer les différents indices des modèles à partir des valeurs du Lden, issues de cartes de bruit et utilisées pour définir l’exposition au bruit des personnes enquêtées. Cette confrontation a montré que les modèles proposés à partir d’expériences menées en laboratoire et couplés à la méthodologie d’estimation des indices à partir des valeurs du Lden permettent une bonne prédiction de la gêne in situ. / Road traffic noise, and in particular powered two-wheeler noise, constitute an important source of noise annoyance. In order to estimate the noise exposure in cities of more than 100 000 inhabitants, the European directive 2002/49/EC requires the elaboration of strategic noise maps, based on the Lden index. This index is also used in exposureresponse relationships, to predict the percentages of annoyed people, by road traffic noise for example. By coupling strategic noise maps and these exposure-response relationships, noise annoyance maps could be established. The relevance of this index to predict noise annoyance in cities is however often questioned, since many influential acoustical factors (e.g. spectral and temporal features) are not considered by this index. The aim of this thesis is to enhance the characterization of noise annoyance due to different compositions of urban road traffic including powered two-wheelers. To achieve this goal, experiments were carried out under controlled conditions. A first study concerned the influence of several acoustical features related to quiet periods and vehicle pass-by noises on the annoyance due to urban road traffic noise. This study demonstrated the influence of the presence of quiet periods and of the number of vehicles within the urban road traffic and to the absence of the influence of the order of the vehicle pass-by noises, the position and duration of quiet periods. These results were used to carry out the physical and perceptual characterization of different compositions of urban road traffic noise. Multilevel regression was used to calculate noise annoyance, by coupling combinations of indices relating to influential acoustical features and an individual factor: noise sensitivity. In cities, road traffic noise is often combined with other noises. In the framework of this thesis, noise exposure to road traffic noise combined with aircraft noise was studied. Therefore, the same work as the one performed for urban road traffic noise was carried out for aircraft noise, leading also to relevant combinations of noise indices. In order to characterize annoyances due to road traffic noise and to aircraft noise in a combined exposure situation, data from the previous experiments and from an experiment dealing with these combined noises were used through an appropriate multilevel regression, as done in literature. The regression allows annoyance models for each noise source to be proposed. Then, total annoyance due to combined noises was studied, in order to highlight the perceptual phenomena related to the combined exposure. Total noise annoyance models were proposed, using proposed annoyance model of each noise source. Finally, these single source annoyance models and total annoyance models were tested using data of a socio-acoustic survey. To do this, a methodology has been proposed to estimate the different indices involved in the annoyance models, from the Lden values obtained from the strategic noise maps and used to define the noise exposure of the respondents. This confrontation showed that the models proposed on the basis of experiments carried out under laboratory conditions and coupled with a methodology of estimation of the noise indices from Lden values, enabled a good prediction of in situ annoyance.

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