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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.
21

Mapeamento e análise de ruído ambiental estudo de caso: Campus Unisinos

Krumenauer, Marcelo 09 August 2016 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-12-15T15:05:04Z No. of bitstreams: 1 Marcelo Krumenauer_.pdf: 69569589 bytes, checksum: e2523784eadef427213d4da3ae49eb6f (MD5) / Made available in DSpace on 2016-12-15T15:05:05Z (GMT). No. of bitstreams: 1 Marcelo Krumenauer_.pdf: 69569589 bytes, checksum: e2523784eadef427213d4da3ae49eb6f (MD5) Previous issue date: 2016-08-09 / UNISINOS - Universidade do Vale do Rio dos Sinos / Os mapas de ruído ou cartas acústicas são amplamente difundidos entre os países da União Europeia e são importantes ferramentas para elaboração de planos de ação e metas para combater a poluição sonora. No Brasil, contudo, poucas são as ações efetivas para a identificação e avaliação das condições de exposição da população ao ruído real. O conhecimento dos níveis reais de ruído permite ao poder público a análise e proposição de medidas e políticas públicas. Nos centros urbanos, cada vez mais a população sofre devido aos efeitos dos elevados níveis de ruídos, principalmente decorrentes do tráfego viário, degradando o meio ambiente e as condições de vida da população. O objetivo do trabalho é desenvolver o mapa de ruído para o Campus da Universidade do Vale do Rio dos Sinos. Para desenvolver este objetivo, foi utilizado o software de previsão acústica CadnaA, aplicando-se os seguintes procedimentos metodológicos: definição da área de estudo; estudo de tráfego da área avaliada (utilizando-se a contagem automática de veículos, através de controladores eletrônicos e cancelas automáticas do Campus); definição de grandezas (meteorológicas, acústicas, tráfego e geométricas); definição de parâmetros de cálculo; modelagem sonora; e validação do ambiente simulado. Para validação do mapa de ruído do Campus, foram avaliados 13 diferentes modelos, com diferentes configurações, comparando-os com os níveis equivalentes de pressão sonora coletados em campo. Os resultados finais indicam um modelo calibrado para a representação do ambiente sonoro do Campus, que com grande diversidade de ambientes de propagação, diferencia-se dos demais ambientes urbanos. Este trabalho justifica-se pelo avanço no reconhecimento e quantificação de níveis de ruídos em áreas externas. / The noise maps or acoustic cards are widely disseminated among of the European Union countries and are important tools for preparing action plans and targets to combat noise pollution. In Brazil, however, there are few effective actions for the identification and evaluation of the conditions of exposure of the population to the real noise. Knowledge of the actual levels of noise allows the government to analyze and propose measures and public policies. In urban centers, increasingly people are suffering from the effects of high noise levels, mainly resulting from road traffic, degrading the environment and living conditions of the population. The objective is to develop a noise map for the Campus of the Universidade do Vale do Rio dos Sinos. To develop this goal, the acoustic prediction software CadnaA was used, applying the following methodological procedures: definition of the study area; the evaluated area traffic study (using the automatic counting of vehicles through electronic controllers and automatic Campus gates); defining quantities (weather, acoustics, traffic and geometric); setting calculation parameters; sound modeling; and validation of the simulated environment. To validate the Campus noise map were evaluated 13 different models, with different settings, comparing them with the equivalent sound pressure level collected in the field. The final results indicate a calibrated model for the representation of the Campus environment sound, which with great diversity of propagation environments, differs from other urban environments. This work is justified by the progress in the recognition and measurement of noise levels outdoors.
22

Tyst stad : En studie om god ljudmiljö och blandstad vid planeringen av högljudda kulturaktiviteter

Wallenius Kral, Martin January 2023 (has links)
I Stockholm pratades det om klubbdöden under 2019 eftersom flera högljudda kulturaktiviteter behövt stänga i innerstaden. Den huvudsakliga anledningen var konflikter mellan boende och kulturaktiviteter om bullerstörningar som naturligt uppstår när människor ska bo, verka och leva i en tät blandstadsmiljö. I Slakthusområdet ska denna problematik bemötas för att bli en nöjes- och evenemangsknutpunkt tillsammans med höga målsättningar om bostadsbyggande i blandstad. Den tidigare forskningen visar på att god ljudmiljö är mer komplext än endast reduceringen av önskade ljud utefter mätbara decibel. I Kulturkvarteren möts förståelsen av god ljudmiljö och blandstaden vid planeringen av högljudda kulturaktiviteter och utgör därför fallet i denna studie. I form av en kvalitativ innehållsanalys studerades planeringens förutsättningar, intentioner och åtgärder för att svara på om god ljudmiljö och blandstad är förenligt vid planeringen av högljudda kulturaktiviteter. För att studera det tillämpades teorin om ljud som en resurs och ljud som oönskat buller tillsammans med teorier om vad som utgör blandstaden. Dokumentstudier innefattade Slakthusområdets planprogram och Kulturkvarterens olika plandokument. Övergripande dokument från myndigheter studerades också för att skapa en större förståelse för planeringens förutsättningar. Intervjuer utförde med en planarkitekt, miljöutredare, nationell bullersamordnare, jurist och akustiker på Boverket, Naturvårdsverket, Miljöförvaltningen och Stockholms stad. Resultaten visar på att, i Kulturkvarteren, har ett defensivt förhållningssätt utgåtts ifrån där kulturaktiviteters ljudnivåer begränsas för att möjliggöra blandstadskvaliteteter. Möjliggörandet av en större variation i funktioner, människor och aktiviteter på den lilla skalan underbygger planeringens intentioner och åtgärder för en ljudmiljö där ljudkällor ska vara i balans med varandra för att inte maskera andra ljud. Bostadens riktvärden för ljud är den centrala faktorn i förutsättningarna för ljudmiljön i blandstaden och planeringens intentioner för den urbana ljudmiljön kunde därför ses som en funktion av bulleråtgärder snarare än direkta intentioner och åtgärder. Planeringen av kulturaktiviteter innebar därför inte en god ljudmiljö där högre kulturella ljud konsolideras i blandstadsmiljön utefter ljudets mening och sociokulturella kontext. Kulturkvarteren som en plats där högre kulturellt ljud görs möjligare, i högre grad, än i resten av innerstaden kunde därför ifrågasättas. Förenligheten i god ljudmiljö och blandstad vid planeringen av högljudda kulturaktivitet i Kulturkvarteren är hög i många aspekter. Högre ljudnivåer i lokaler möjliggörs och en god ljudmiljö utomhus och i bostäder säkerställs baserat på effekten på människors fysiologiska hälsa. Det förutsätter däremot en förståelse av god ljudmiljö som tystare där högre ljud, oberoende av dess subjektiva uppskattning, ska reduceras eller kontrolleras. Förenligheten i god ljudmiljö och blandstad är därför kontextuell. Högre ljudnivåer som en resurs kan innebär goda ljudkvaliteter utifrån platsens sociokulturella aspekt och ljudets mening men det är mindre förenligt med blandstaden på grund av riktvärdenas tillämpning men även planeringen intentioner för blandstadskvaliteter på den lilla skalan. Möjliggörandet av högre kulturljud i Kulturkvarteren innebar en reglering som säkerställer att riktvärden inte överstigs och inte att högre ljudnivåer möjliggörs i den urbana miljön. Jag anser därför att god ljudmiljö måste lyftas i bredare mening för att möjliggöra en större variation av ljudmiljöer som kan skapa platser i innerstaden för de kulturaktiviteter som inte ryms under riktvärdenas mätbarhet men som tillför andra goda ljudkvaliteteter. / In Stockholm, there was a discussion about the death of clubs in 2019 due to the closure of several vibrant cultural activities in the city centre. The main reason behind this was conflicts between residents and cultural activities regarding noise disturbances that naturally occur when people live, work, and coexist in a densely populated urban environment. In the Slakthusområdet area, efforts are being made to address this issue and transform it into a hub for entertainment and events, while also setting ambitious goals for mixed-use residential development. Previous research indicates that a good sound environment is more complex than simply reducing the desired sounds based on measurable decibels. In one of Slakthusområdets areas, Kulturkvarteren, the understanding of a good sound environment meets mixed-use urban development when planning for loud cultural activities, thereby making it the case of the study. Using a qualitative content analysis approach, this study examines the conditions, intentions, and measures taken in the planning process to determine whether a good sound environment and mixed-use urban development are compatible when planning for loud cultural activities. To study this, a theoretical framework consisting of sound as a resource and sound as unwanted noise was applied. This was then studied by applying theory regarding what constitutes the mixed-use city. The study involved examining documents such as the Slakthusområdet's master plan and various planning documents related to the Kulturkvarteren. Additionally, overarching documents from relevant authorities were also studied to gain a better understanding of the planning conditions. Interviews were conducted with a planning architect, environmental assessor, national noise coordinator, lawyer, and acoustician from Boverket, Naturvårdsverket, Miljöförvaltningen, and the City of Stockholm.  The findings demonstrate that, in Kulturkvarteren, a defensive approach has been taken, wherein the sound levels of cultural activities are limited to enable mixed-use qualities. Facilitating a greater variety of functions, people, and activities on a small scale supports the intentions and measures of the planning process aimed at achieving a sound environment where sound sources are balanced to avoid masking other sounds. The residential sound standards serve as a pivotal factor in shaping the acoustic conditions in the mixed-use city, and the planning intentions for the urban sound environment can therefore be viewed as a function of noise control rather than direct intentions and measures. Consequently, the planning of cultural activities does not result in a good sound environment where higher cultural sounds are integrated into the mixed-use environment based on the meaning of sound and sociocultural context. Therefore, the notion of the Kulturkvarteren as a place where higher cultural noise levels are enabled compared to the rest of the city could be subject to scrutiny. The compatibility between a good sound environment and mixed-use in the planning of loud cultural activities in Kulturkvarteren is favourable in several aspects. Higher sound levels indoors are made possible, and a favourable sound environment is ensured outdoors and in residential areas based on the impact on people's physiological well-being. However, this presupposes an understanding of a good sound environment as being quieter, where higher sounds, regardless of their subjective appreciation, should be reduced or controlled. Therefore, the compatibility between a good sound environment and mixed-use is context dependent. Higher sound levels, as a resource, may provide favourable sound qualities based on the sociocultural aspect of the location and the meaning of sound. However, it is less compatible with the mixed-use city due to the application of sound standards and the planning intentions for mixed-use qualities on a small scale. The facilitation of higher cultural sounds in the Kulturkvarteren entailed regulation to ensure that sound standards are not exceeded, rather than enabling higher sound levels in the urban environment. Hence, I argue that a broader understanding of a good sound environment is necessary to allow for a greater variety of sound environments that can create spaces in the city centre for cultural activities that fall outside the scope of measurable sound standards but contribute to other favourable sound qualities.
23

Visual simultaneous localization and mapping in a noisy static environment

Makhubela, J. K. 03 1900 (has links)
M. Tech. (Department of Information and Communication Technology, Faculty of Applied and Computer Sciences), Vaal University of Technology / Simultaneous Localization and Mapping (SLAM) has seen tremendous interest amongst the research community in recent years due to its ability to make the robot truly independent in navigation. Visual Simultaneous Localization and Mapping (VSLAM) is when an autonomous mobile robot is embedded with a vision sensor such as monocular, stereo vision, omnidirectional or Red Green Blue Depth (RGBD) camera to localize and map an unknown environment. The purpose of this research is to address the problem of environmental noise, such as light intensity in a static environment, which has been an issue that makes a Visual Simultaneous Localization and Mapping (VSLAM) system to be ineffective. In this study, we have introduced a Light Filtering Algorithm into the Visual Simultaneous Localization and Mapping (VSLAM) method to reduce the amount of noise in order to improve the robustness of the system in a static environment, together with the Extended Kalman Filter (EKF) algorithm for localization and mapping and A* algorithm for navigation. Simulation is utilized to execute experimental performance. Experimental results show a 60% landmark or landfeature detection of the total landmark or landfeature within a simulation environment and a root mean square error (RMSE) of 0.13m, which is minimal when compared with other Simultaneous Localization and Mapping (SLAM) systems from literature. The inclusion of a Light Filtering Algorithm has enabled the Visual Simultaneous Localization and Mapping (VSLAM) system to navigate in an obscure environment.
24

The Effects of Auditory Stimuli on Stress Levels of Adult Patients in the Critical Care Setting

Ellermets, Jessica 01 August 2015 (has links)
The purpose of this review of literature is to explore the effects of interventional and environmental auditory stimuli on the adult critical care population. Current research has yet to compare and contrast the effectiveness of various interventional auditory stimuli on stress relief, an oversight this thesis aims to remedy. Modern day critical care settings demand the identification of the most therapeutic interventional auditory stimulus and the most stress-inducing environmental stimuli, so that interventions can be made to optimize patient stress levels and improve outcomes. Suggestions will be made on how to simultaneously reduce harmful or stress inducing auditory stimuli in the critical care setting and implement the optimal stress-relieving interventional auditory stimuli.
25

[en] ASSESSMENT OF COMPLIANCE TO ENVIRONMENTAL LEGISLATION OF SOUND PRESSURE LEVELS IN POWER SUBSTATIONS / [pt] AVALIAÇÃO DA CONFORMIDADE DA PRESSÃO SONORA EM SUBESTAÇÕES DE ENERGIA AOS NÍVEIS IMPOSTOS PELA LEGISLAÇÃO AMBIENTAL APLICÁVEL

08 October 2021 (has links)
[pt] Esta dissertação de mestrado tem por objetivo investigar os níveis de pressão sonora resultantes do funcionamento de subestações de energia, instaladas em áreas de considerável densidade urbana. A metodologia de desenvolvimento do trabalho fundamenta-se em dois preceitos: (i) em um programa estruturado de medições da pressão sonora e (ii) na conformidade dos valores medidos com os limites impostos pela rígida legislação ambiental aplicável. A motivação pelo tema da pesquisa resultou de uma demanda de uma concessionária de energia da cidade do Rio de Janeiro que, para se defender de uma ação civil pública impetrada pelos moradores da vizinhança de uma subestação, contratou o PósMQI para desenvolver um projeto de P&D capaz de avaliar alternativas de mitigação do ruído acústico na vizinhança de subestações de energia em funcionamento em zonas urbanas de alta densidade populacional. No que concerne aos resultados da pesquisa, a dissertação descreve e analisa os resultados de um programa estruturado de medições da pressão sonora na vizinhança de dez subestações inseridas em zonas urbanas. Como conclusão, foi possível mostrar que, de uma maneira geral, todas as subestações estudadas geram um nível de ruído muito próximo aos limites máximos impostos pela legislação ambiental aplicável. Desenvolvida em sintonia com um projeto de P&D (Light/Aneel Ref. 0128/2019), que propõe alternativas tecnológicas para mitigar o nível da pressão sonora em subestações de energia, a pesquisa de mestrado desenvolveu extensa revisão da literatura especializada sobre o tema e uma análise crítica do acervo normativo, diretivas e leis aplicáveis ao controle de ruído acústico em zonas urbanas. / [en] This master s research aims to investigate the sound pressure levels resulting from the operation of power substations, installed in areas of considerable urban density. The methodology for developing the work is based on two precepts: (i) a structured program of sound pressure measurements and (ii) the compliance of the measured values with the limits imposed by the strict applicable environmental legislation. The motivation for the research theme resulted from a demand from an electricity utility in the city of Rio de Janeiro that, to defend itself from a public civil action filed by residents of a nearby substation, hired PósMQI to develop a capable R&D project to evaluate alternatives for mitigating acoustic noise in the vicinity of power substations operating in urban areas with high population density. Regarding the research results, the dissertation describes and analyzes the outcomes of a structured program of sound pressure measurements in the vicinity of ten substations located in urban areas. In conclusion, it was possible to show that, in general, all studied substations generate a noise level very close to the maximum limits imposed by the applicable environmental legislation. Developed in line with an R&D project (Light/Aneel Ref. 0128/2019), which proposes technological alternatives to mitigate the level of sound pressure in power substations, the master s research developed an extensive review of the specialized literature on the subject and a critical analysis of the normative asset of, directives and laws applicable to the control of acoustic noise in urban areas.
26

Relations entre l’exposition au bruit environnemental total et des transports et l’infarctus du myocarde et les accidents vasculaires cérébraux et effet médiateur de l’hypertension sur ces relations

Yankoty, Larisa Inès 11 1900 (has links)
Résumé Le bruit environnemental aurait des effets négatifs majeurs sur le système cardiovasculaire. Cependant, les preuves épidémiologiques proviennent majoritairement de l’Europe et restent largement limitées aux associations avec l’hypertension (HT) et l’ensemble des maladies coronariennes combinées (incluant l’infarctus du myocarde, IM). Les accidents vasculaires cérébraux (AVC) qui constituent pourtant la deuxième cause de décès dans le monde ont été très peu étudiés. De plus, la plupart des études portant sur les effets cardiovasculaires du bruit environnemental ont surtout estimé l’exposition au bruit des transports (routier et aérien) et non le bruit environnemental total (provenant de toutes les sources extérieures) auquel les individus sont généralement exposés dans leur environnement. Aussi, aucune étude n’a exploré par des analyses de médiation si l’effet du bruit sur les maladies cardiovasculaires (MCV) comme l’IM ou les AVC « passe » ou non par l’HT qui est un important facteur de risque des MCV. L’objectif de cette thèse était d’examiner les associations entre l’exposition résidentielle prolongée au bruit environnemental total et des transports et l’incidence d’IM et d’AVC (incluant l’AVC ischémique et hémorragique) dans la population adulte de Montréal, Canada. Cette thèse visait également à évaluer le rôle médiateur de l’HT dans ces associations. Des cohortes rétrospectives ouvertes (pour l’IM et les AVC) constituées d’individus âgés de ≥ 45 ans résidant à Montréal et sans antécédent d’IM ou d’AVC ont été construites à partir des données du Système intégré de surveillance des maladies chroniques du Québec pour la période 2000-2014. Nous avons utilisé trois méthodes différentes pour estimer l’exposition au bruit résidentiel : 1) bruit environnemental total estimé avec un modèle de type « Land Use Regression (LUR) »; 2) bruit du transport routier estimé avec le modèle de propagation CadnaA et 3) les distances aux sources de bruit du transport (routes, aéroport et chemins de fer). Les cas incidents d’IM, d’AVC et d’HT ont été identifiés à partir d’algorithmes validés, basés sur les diagnostics d’hospitalisations et de consultations médicales à l’urgence et en cabinet. Des modèles de Cox (avec l’âge comme axe de temps) stratifiés pour le sexe, ajustés pour l’année calendrier, l’indice de défavorisation matérielle et la pollution routière (dioxyde d’azote) et indirectement ajustés pour le tabagisme ont permis d’estimer les différentes associations. La méthode contrefactuelle a été utilisée pour estimer les effets direct et indirect de l’analyse de médiation par l’HT; dans cette analyse, un modèle logistique a été utilisé pour relier le bruit total à l’HT. Plus d’un million d’individus totalisant plus de 9,000,000 personnes-années ont été suivis de 2000 à 2014 dans chaque cohorte (IM et AVC). Nous avons trouvé des associations positives entre le bruit environnemental total (estimé avec LUR) et l’incidence de l’IM et des AVC. Les rapports de taux de risque (hazard ratio : HR) ajustés étaient respectivement de 1,12 (Intervalle de confiance [IC] à 95 % : 1,08-1,15) et 1,06 (IC 95 % : 1,03-1,09) pour chaque augmentation de 10 décibels A (dBA) des niveaux de bruit équivalent total sur 24h (LAeq24h). L’AVC ischémique était aussi associé au bruit environnemental total (HR par 10 dBA : 1.08; IC 95 % : 1,04-1,12) mais pas l’AVC hémorragique (HR par 10 dBA : 0,97; IC 95 % : 0,90-1,04). La précision des niveaux de bruit routier estimés avec le modèle de propagation CadnaA était faible, et l’association entre le bruit routier et l’IM négative (HR par 10 dBA : 0,99; IC 95 % : 0,98-1,00). Les résultats avec les distances aux sources de bruit étaient aussi surprenants. La proximité aux routes majeures et autoroutes n’étaient pas associée à l’IM (ex : HR comparant ≤50 versus > 500 m : 1,00; IC 95 % : 0,97-1,03 pour les routes majeures) tandis que la proximité aux chemins de fer l’était (HR pour ≤100 versus >1000 m : 1,07; IC 95 % : 1,01-1,14). Une association négative a été observée avec la proximité à la zone bruyante de l’aéroport). L’HT n’apparaissait pas comme un médiateur des associations entre le bruit environnemental total et l’incidence de l’IM ou des AVC, bien que l’HT soit aussi associée au bruit environnemental total (Rapport de Cotes par IQR de 5,5 dBA : 1,05, IC 95 % : 1,04-1,06 pour l’IM; et 1,05, IC 95 % : 1,05-1,06 pour les AVC). Les résultats de nos travaux basés sur le bruit environnemental total suggèrent que le bruit environnemental est associé à l’incidence de l’IM et des AVC dans une ville canadienne. L’HT n’apparaît pas comme un médiateur dans la relation entre le bruit et ces MCV. Les distances sont des indicateurs non spécifiques de l’exposition au bruit et le développement d’estimés d’exposition plus précis basés sur des modèles de propagation sont nécessaires pour quantifier les risques associés spécifiquement au bruit routier afin de les comparer à ceux d’autres villes. À Montréal, au Québec et au Canada, comme en Europe, le bruit environnemental contribue au fardeau de la maladie et il est important d’envisager des actions préventives pour réduire l’exposition des populations. / Abstract Environmental noise has major negative effects on the cardiovascular system. However, epidemiological evidence comes mainly from Europe and remains largely limited to associations with hypertension (HT) and all combined coronary heart disease (including myocardial infarction, MI). Stroke, which is the second leading cause of death in the world, has been very little studied. In addition, most studies examining the cardiovascular effects of environmental noise have mainly estimated exposure to transport noise (road and air), not the total environmental noise (from all sources) to which individuals are generally exposed in their environment. Also, no study has explored with mediation analyses whether the effect of noise on cardiovascular diseases (CVD) such as MI or stroke “passes” or not through HT which is an important risk factor for CVD. The objective of this thesis was to examine the associations between long-term residential exposure to total environmental and transport noise and the incidence of MI and strokes (including ischemic and hemorrhagic stroke) in the adult population of Montreal, Canada. This thesis also aimed to assess the mediating effect of HT on these relationships. Open retrospective cohorts (for MI and strokes) of individuals aged ≥ 45 years residing in Montreal and without a history of MI or stroke were constructed from the Quebec Integrated Chronic Disease Surveillance System for the period 2000-2014. We used three different methods to estimate residential noise exposure: 1) total environmental noise estimated with a « Land Use Regression (LUR) » model; 2) road transport noise estimated with the CadnaA propagation model and 3) distances to transport noise sources (roads, airport, rail). Incident cases of MI, stroke and HT were identified using validated algorithms, based on diagnoses of hospitalizations and medical consultations at the emergency room and in physician offices. Cox models (with age as the time axis) stratified by sex, adjusted for the calendar year, material deprivation index and road pollution (nitrogen dioxide) and indirectly adjusted for smoking were used to estimate the different associations. The counterfactual method was used to estimate the direct and indirect effects of the mediation analysis by HT; a logistic regression model was used to relate total noise to HT in this analysis. Over one million individuals totalizing over 9,000,000 person-years were followed from 2000 to 2014 in each cohort (MI and stroke). We found positive associations between total environmental noise (estimated with LUR) and the incidence of MI and stroke. The adjusted hazard ratios (HR) were 1.12 (95% confidence interval [CI]: 1.08-1.15) and 1.06 (95% CI: 1.03-1, 09) for each 10 decibel A (dBA) increase in total equivalent noise levels over 24 hours (LAeq24h). Total environmental noise was associated with ischemic stroke (HR per 10 dBA: 1.08; 95% CI: 1.04-1.12) but not with hemorrhagic stroke (HR per 10 dBA: 0.97; 95% CI: 0.90-1.04). The precision of road noise levels estimated from the propagation model CadnaA was low and the association between road noise levels and MI negative (HR per 10 dBA: 0.99; 95% CI: 0.98-1.00). The results with distances to noise sources were also surprising. Proximity to major roads and highways were not associated with MI (e.g. HR comparing ≤50 versus> 500 m: 1.00; 95% CI: 0.97-1.03 for major roads) while the proximity to railways was positively associated with MI (HR for ≤100 versus> 1,000 m: 1.07; 95% CI: 1.01-1.14). A negative association was observed with the proximity to the noisy area of the airport (HR <1 versus> 1,000 m: 0.88; 95% CI: 0.81-0.96). HT did not appear to mediate the associations between total environmental noise and the incidence of MI or stroke, although HT was also associated with total environmental noise (Odds Ratios by IQR of 5.5 dBA increase: 1.05, 95%CI: 1.04-1.06 for MI; and 1.05, 95%CI: 1.05-1.06 for stroke). The results of our research based on total environmental noise suggest that environmental noise is associated with the incidence of MI and stroke in a Canadian city. HT does not appear to mediate the relationship between noise and these CVDs. Distances are non-specific indicators of noise exposure and the development of more precise exposure estimates based on propagation models is needed to quantify the risks associated specifically with road noise in order to compare them with those of other cities. In Montreal, Quebec and Canada, as in Europe, environmental noise contributes to the burden of disease, and it is important to consider preventive actions to reduce the exposure of populations.
27

Perceptually meaningful time and frequency resolution in applying dialogue enhancement in noisy environments : Dialogue Enhancement research

PATIL, SUSHANTH January 2023 (has links)
Dialogue Enhancement (DE) is a process used in audio delivery systems to improve the clarity, intelligibility, and overall quality of the spoken dialogue in audio content. It is primarily used when dialogue is masked by music, surrounding noise, or other audio sources. This thesis project involves experiments to find the optimal time and frequency resolution needed for a DE system. The time resolution focuses on experimenting with various attack/release times for a DE system. The frequency domain analysis investigates whether people prefer a noise spectrum-dependent gain over a conventional full-band gain. The research methodology comprises three main parts. The first part focuses on system setup and choosing content/vectors to be used for the experiments. Next, the experiments are designed for time and frequency resolution. An exponential smoothing model is used to amplify/attenuate the dialogue stream at various times of attack/release. For the frequency counterpart, a banded gain model is designed which uses banded noise levels as input. Subsequently, a modified subjective listening test is designed to evaluate the experiments designed. The responses recorded for various types of content-noise combinations from the listeners are recorded and analyzed. Finally, the main outcome of this research emphasizes the advantages of a DE system. Further, it paves the way for further exploration of DE models and rigorous testing schemes with expert listeners. / Dialogue Enhancement (DE) är en process som används i ljudleveranssystem för att förbättra tydligheten, förståeligheten och den övergripande kvaliteten på den talade dialogen i ljudinnehåll. Det används främst när dialog maskeras av musik, omgivande brus eller andra ljudkällor. Detta examensarbete omfattar experiment för att hitta den optimala tids- och frekvensupplösningen för ett DEsystem. Tidsupplösningsexperimenten fokuserar på olika attack- och releasetider för ett DE-system. Frekvensdomänanalysen undersöker om människor föredrar en brusspektrumberoende förstärkning framför en konventionell fullbandsförstärkning. Forskningsmetodiken består av tre huvuddelar. Den första delen fokuserar på systeminställning och val av innehåll/vektorer som ska användas för experimenten. Därefter designas tids- och frekvensupplösningsexperimenten. En exponentiell tidsenvelopp används för att förstärka/dämpa dialogen vid olika tider för attack/release. För frekvensdomänexperimenten används en bandad förstärkningsmodell som använder bandade brusnivåer som insignal. I den tredje delen utformas ett subjektivt lyssningstest för att utvärdera experimenten. Lyssnarnas svar för olika typer av innehåll-bruskombinationer registreras och analyseras. Det huvudsakliga resultatet av denna forskning betonar fördelarna med ett DEsystem. Vidare banar det väg för utforskning av fler DE-modeller och rigorösa testscheman med expertlyssnare.

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