No description available.

No / The acoustical effects of hedges result from a combination of physical noise reduction and their influences on perception. This study investigates the physical noise reduction so as to enable estimation of its relative importance. Different in-situ methods have been used to measure noise shielding by hedges. These include a statistical pass-by experiment where the real insertion loss of a hedge could be measured, three controlled pass-by experiments using a reference microphone at close distance, and transmission loss measurements using a point source. Thick dense hedges are found to provide only a small total A-weighted light vehicle noise reduction at low speeds. Measured insertion losses range from 1.1 dBA to 3.6 dBA. The higher noise reductions are found to be associated with an increased ground effect.

Objectives.The general objectives of this dissertationwere to examine the effects of acute exposure to meaningfulirrelevant speech and road traffic noise on memory performance,and to explore annoyance responses to noise exposure in theschool environment for pupils and teachers in different agegroups. Methods. The thesis comprises seven papers, representingdifferent methodological approaches: experiments, surveystudies and interviews. In the experiments, reported in PapersI-V, 288 pupils and teachers participated in the age groups,13-14 years (n=96), 18-20 years (n=96), 35-45 years (n=48) and55-65 years (n=48). The subjects were randomly assigned to oneof three conditions: (a) meaningful irrelevant speech, (b) roadtraffic noise, and (c) silence. The equivalent sound level inthe noise conditions was set to 66 dB(A). A test batteryreflecting episodic and semantic memory were used. The surveystudies, reported in Paper VI and VII, included 207 pupils(M=13.5) and 166 teachers (M=45.9). Two separate questionnairesmainly comprising items about annoyance, noise sensitivity andstress symptoms were administered. Paper VI presents results offocus group interviews (n=16) treating the main topics:disturbing sounds, emotions, ongoing activity, and suggestionsconcerning future changes. Results. The overall findings showedthat both noise sources affected episodic and semantic memoryto the same degree for all age groups. The results indicatedthat the similarity of semantic content between noise and thetask at hand was not the only suitable explanation model, sincea non-speech noise impaired memory as much as speech. Resultsalso indicated that attention effects did notmediate the obtained noise effects and that the noise effectsdid not differ between age groups. Therefore, it seemedunlikely that different memory and attentional capacities stoodout as explanatory factors of the memory effects. Sinceperformances of both episodic and semantic memory tasks wereimpaired, the explanation based on level of access to long-termmemory was also ruled out. However, the episodic memory task,reading comprehension, stood out to be most impaired by noise,suggesting that complexity of the task to perform was ofimportance. For reading comprehension there was also adifferent noise pattern obtained. Participants performance wasin this task, more impaired by meaningful irrelevant speechthan by road traffic noise. This effect indicated thatmeaningful irrelevant speech might reduce the availablecognitive resources necessary for learning the text. Theannoyance models derived from the survey studies indicated thatsensitivity acted as a mediator between hearing status andannoyance, with stress symptoms as an outcome. Whetherannoyance arises or not was also determined by control andpredictability of the noise. In the interviews a differentannoyance pattern was found, in that stress symptoms appearedto be a determinant of annoyance. To be involved, respected,take own responsibility and respect others were suggestions onhow to change the environment to become more silent. Conclusions.For both pupils and teachers acute exposureto meaningful irrelevant speech and road traffic noiseinfluenced both the achieving and providing of knowledge. Acommon annoyance pattern was also found for pupils andteachers, where individual and situational factors were ofimportance. To achieve a more silent school environment in thefuture, the pupils pointed out that the interaction betweenthemselves and their teachers was of importance. Key words:Noise, meaningful irrelevant speech, roadtraffic noise, memory, age groups, school environment, pupils,teachers

Objectives.The general objectives of this dissertationwere to examine the effects of acute exposure to meaningfulirrelevant speech and road traffic noise on memory performance,and to explore annoyance responses to noise exposure in theschool environment for pupils and teachers in different agegroups. Methods. The thesis comprises seven papers, representingdifferent methodological approaches: experiments, surveystudies and interviews. In the experiments, reported in PapersI-V, 288 pupils and teachers participated in the age groups,13-14 years (n=96), 18-20 years (n=96), 35-45 years (n=48) and55-65 years (n=48). The subjects were randomly assigned to oneof three conditions: (a) meaningful irrelevant speech, (b) roadtraffic noise, and (c) silence. The equivalent sound level inthe noise conditions was set to 66 dB(A). A test batteryreflecting episodic and semantic memory were used. The surveystudies, reported in Paper VI and VII, included 207 pupils(M=13.5) and 166 teachers (M=45.9). Two separate questionnairesmainly comprising items about annoyance, noise sensitivity andstress symptoms were administered. Paper VI presents results offocus group interviews (n=16) treating the main topics:disturbing sounds, emotions, ongoing activity, and suggestionsconcerning future changes. Results. The overall findings showedthat both noise sources affected episodic and semantic memoryto the same degree for all age groups. The results indicatedthat the similarity of semantic content between noise and thetask at hand was not the only suitable explanation model, sincea non-speech noise impaired memory as much as speech. Resultsalso indicated that attention effects did notmediate the obtained noise effects and that the noise effectsdid not differ between age groups. Therefore, it seemedunlikely that different memory and attentional capacities stoodout as explanatory factors of the memory effects. Sinceperformances of both episodic and semantic memory tasks wereimpaired, the explanation based on level of access to long-termmemory was also ruled out. However, the episodic memory task,reading comprehension, stood out to be most impaired by noise,suggesting that complexity of the task to perform was ofimportance. For reading comprehension there was also adifferent noise pattern obtained. Participants performance wasin this task, more impaired by meaningful irrelevant speechthan by road traffic noise. This effect indicated thatmeaningful irrelevant speech might reduce the availablecognitive resources necessary for learning the text. Theannoyance models derived from the survey studies indicated thatsensitivity acted as a mediator between hearing status andannoyance, with stress symptoms as an outcome. Whetherannoyance arises or not was also determined by control andpredictability of the noise. In the interviews a differentannoyance pattern was found, in that stress symptoms appearedto be a determinant of annoyance. To be involved, respected,take own responsibility and respect others were suggestions onhow to change the environment to become more silent. Conclusions.For both pupils and teachers acute exposureto meaningful irrelevant speech and road traffic noiseinfluenced both the achieving and providing of knowledge. Acommon annoyance pattern was also found for pupils andteachers, where individual and situational factors were ofimportance. To achieve a more silent school environment in thefuture, the pupils pointed out that the interaction betweenthemselves and their teachers was of importance. Key words:Noise, meaningful irrelevant speech, roadtraffic noise, memory, age groups, school environment, pupils,teachers

<p><b>Objectives.</b>The general objectives of this dissertationwere to examine the effects of acute exposure to meaningfulirrelevant speech and road traffic noise on memory performance,and to explore annoyance responses to noise exposure in theschool environment for pupils and teachers in different agegroups.</p><p><b>Methods</b>. The thesis comprises seven papers, representingdifferent methodological approaches: experiments, surveystudies and interviews. In the experiments, reported in PapersI-V, 288 pupils and teachers participated in the age groups,13-14 years (n=96), 18-20 years (n=96), 35-45 years (n=48) and55-65 years (n=48). The subjects were randomly assigned to oneof three conditions: (a) meaningful irrelevant speech, (b) roadtraffic noise, and (c) silence. The equivalent sound level inthe noise conditions was set to 66 dB(A). A test batteryreflecting episodic and semantic memory were used. The surveystudies, reported in Paper VI and VII, included 207 pupils(M=13.5) and 166 teachers (M=45.9). Two separate questionnairesmainly comprising items about annoyance, noise sensitivity andstress symptoms were administered. Paper VI presents results offocus group interviews (n=16) treating the main topics:disturbing sounds, emotions, ongoing activity, and suggestionsconcerning future changes. Results. The overall findings showedthat both noise sources affected episodic and semantic memoryto the same degree for all age groups. The results indicatedthat the similarity of semantic content between noise and thetask at hand was not the only suitable explanation model, sincea non-speech noise impaired memory as much as speech.</p><p><b>Results</b>also indicated that attention effects did notmediate the obtained noise effects and that the noise effectsdid not differ between age groups. Therefore, it seemedunlikely that different memory and attentional capacities stoodout as explanatory factors of the memory effects. Sinceperformances of both episodic and semantic memory tasks wereimpaired, the explanation based on level of access to long-termmemory was also ruled out. However, the episodic memory task,reading comprehension, stood out to be most impaired by noise,suggesting that complexity of the task to perform was ofimportance. For reading comprehension there was also adifferent noise pattern obtained. Participants performance wasin this task, more impaired by meaningful irrelevant speechthan by road traffic noise. This effect indicated thatmeaningful irrelevant speech might reduce the availablecognitive resources necessary for learning the text. Theannoyance models derived from the survey studies indicated thatsensitivity acted as a mediator between hearing status andannoyance, with stress symptoms as an outcome. Whetherannoyance arises or not was also determined by control andpredictability of the noise. In the interviews a differentannoyance pattern was found, in that stress symptoms appearedto be a determinant of annoyance. To be involved, respected,take own responsibility and respect others were suggestions onhow to change the environment to become more silent.</p><p><b>Conclusions.</b>For both pupils and teachers acute exposureto meaningful irrelevant speech and road traffic noiseinfluenced both the achieving and providing of knowledge. Acommon annoyance pattern was also found for pupils andteachers, where individual and situational factors were ofimportance. To achieve a more silent school environment in thefuture, the pupils pointed out that the interaction betweenthemselves and their teachers was of importance.</p><p><b>Key words:</b>Noise, meaningful irrelevant speech, roadtraffic noise, memory, age groups, school environment, pupils,teachers</p>

In a time when urban areas continue to expand, environmental noise pollution especially from road traffic remains a big challenge. This study was aimed at using open-source GIS tools to predict road traffic noise pollution using the mid-sized city of Gävle as a case study. The noise indicators measured were the equivalent day (Lday), evening (Levening), nighttime (Lnight), and the equivalent daily average (Lden). Traffic data (composition and flow of vehicles on selected roads), traffic source characteristics (road gradient, road surface type), and buildings (geometry) were integrated into Quantum GIS (QGIS) using the CNOSSOS-EU prediction method packaged in OpeNoise, a QGIS plug-in. The resultant noise levels at receiver points were interpolated using the Inverse Distance Weighting method to create noise maps for the city.  The results showed the maximum equivalent day, evening, nighttime predicted noise levels at 85 dB (A), 80 dB (A), 75 dB (A) respectively while the maximum for overall daily average noise level predicted was 85 dB (A). These limits far exceed population exposure threshold limits for the onset of annoyance (55 dB (A)) and sleep disturbance (40 dB (A)). This result is indicative of a poor sound acoustic environment. The pattern of noise level across the city was found to follow street connectivity and traffic intensity. The maximum noise levels were clustered around the highway. Within the city, areas with the highest noise levels were found close to main roads. Residential areas served by service roads were areas with the lowest noise levels. Predicted daytime noise levels (Lday) were compared with 60-second measurements of equivalent noise levels measured at 85 locations during the day in residential and mixed land use areas in the city. The mean of differences between predicted and observed noise levels was found at +1 dB for both residential and areas of mixed land use respectively. Correlation and regression analyses performed for observed and predicted values showed an initial weak positive association with a correlation coefficient of 0.21. However, when outliers were excluded, a correlation coefficient of 0.69 was observed indicating a strong association and linear relationship between the observed and predicted noise levels. Most outliers were underestimations recorded in residential areas at hidden facades. These were attributed to local effects at the measuring locations and assumptions made for building diffraction. The application of the CNOSSOS-EU method in this study did not consider attenuation from ground reflection and terrain effects. Despite these limitations, the results show that the CNOSSOS-EU has good predictive power. However, this study has only been exploratory in nature. It is recommended that further studies be performed with this model as well as in comparison with other models to find the one that best reflects the acoustic environment of the city. A wide application of the CNOSSOS-EU method across several cities will be integral in increasing our understanding of its strengths and weaknesses.

In my thesis I deal with the effects of noise on real estate prices in our capital city. The aim is to estimate the traffic noise impact on property prices, using the hedonic price method. Hedonic price analysis is a useful tool for evaluating the impact of environmental policies, especially for assessing measures aiming to reduce traffic noise, and for apprising landscape architecture during the forming of green quiet areas in the city. In the theoretical part of the thesis I deal with the noise characteristics, hedonic price method, and searches of foreign studies that are centered on the benefits of the silence in households. From these studies, I deduced how the noise affects the real estate market, defined the determinants of the real estate valuation, and showed the appropriate format of these determining variables. The practical part of my work focuses on estimating the effect of particular characteristics of a property on its price. From the noise and real estate price data plotted on the map of Prague, I evaluate the relationship between the noise reading and the real estate price, using the econometric analysis. According to my findings, the negative correlation has been proven to be of a significant measure.

The development of cities and population growth have led, among other urban problems, the increase in sound pressure levels of environmental noise. With the overcrowding of cities, the roads start to host large flows of vehicles, among other sound sources. These factors, coupled with the layout and massing of buildings, make the road a polluter responsible for sound pressure levels highly detrimental to health. In Brazil, noise has not been considered by urban planning policies. This study aims to assess the current conditions of urban noise pollution due to vehicular traffic on the downtown of Chapecó - SC. To this end, we sought to map the sound pressure levels, compare them to the municipal and federal laws relating to urban noise, to relate the sound descriptors of the traffic noise with the volume of traffic, to relate the geometry of the built environment with levels of sound pressure and compare the results with the rates proposed by the urban plan of the municipality. To conduct the survey data, was defined a mesh grid from which were located 14 measuring points. Data collection was performed at peak times and these data have been divided into acoustic quantities, geometrical quantities, quantities of traffic and meteorological quantities. The sound pressure levels collected from the study area had higher than those recommended by national standards at all times and points of measurement. From the linear regression analysis between the sound descriptors and flow of vehicular traffic, it was realized that the LAeq is not sufficient to explain the vehicular noise, because the variation of the LAeq is influenced not only by the variation in the number of vehicles, but also by the features the built environment of the road. The variation of LA90 and LA50 sound descriptors showed better correlation with the variation of the flow of vehicular traffic. The urbanistic indices proposed by the plan of the municipality stimulate the future shape of urban canyons, which can aggravate the problems related to noise from vehicular traffic in the local community. / O desenvolvimento das cidades e o crescimento demográfico têm acarretado, entre outros problemas urbanos, o aumento dos níveis de pressão sonora do ruído ambiental. Com a aglomeração dos centros urbanos, as vias passam a abrigar grandes fluxos de veículos, entre outras fontes sonoras. Esses fatores, aliados à disposição e à volumetria das edificações, tornam o tráfego rodoviário um poluidor acústico responsável por níveis de pressão sonora altamente prejudiciais à saúde. No Brasil, o ruído não tem sido considerado pelas políticas de planejamento urbano. O presente estudo tem por objetivo avaliar as condições atuais de poluição sonora urbana devido ao tráfego veicular em área central do município de Chapecó SC. Para tanto, buscou-se mapear os níveis de pressão sonora, comparar os mesmos à legislação municipal e federal referente ao ruído urbano, relacionar os descritores sonoros do ruído de tráfego com o volume de tráfego, relacionar a geometria do ambiente construído com os níveis de pressão sonora e comparar os resultados com os índices urbanísticos propostos pelo plano diretor do município. Para realização do levantamento de dados, foi definida uma malha quadriculada a partir da qual foram localizados 14 pontos de medição. O estudo delimitou a coleta de dados aos horários de pico e estes dados apresentam-se divididos em grandezas acústicas, grandezas geométricas, grandezas de tráfego e grandezas meteorológicas. Os níveis de pressão sonora coletados da área de estudo se apresentaram superiores aos preconizados pelas normativas nacionais em todos os horários e pontos de medição. A partir das análises de regressão linear entre os descritores sonoros e o fluxo de tráfego de veículos, percebeu-se que o LAeq não é suficiente para explicar o ruído veicular, uma vez que a variação do LAeq sofre influência não só da variação no número de veículos, como também das características do ambiente construído da via. A variação dos descritores sonoros LA90 e LA50 demonstraram melhor correlação com a variação do fluxo de tráfego veicular. Os índices urbanísticos propostos pelo plano diretor do município estimulam a configuração futura de cânions urbanos, o que pode agravar os problemas relacionados ao ruído de tráfego veicular enfrentados pela comunidade local.

Trafikbuller är den miljöstörning som påverkar flest människor i Sverige. Studier visar att buller kan påverka människors hälsa genom att orsaka hörselskador, stress, sömnsvårigheter och i förlängningen hjärt- och kärlsjukdomar. Idag byggs städerna i Sverige allt tätare, vilket gör att antalet bullerstörda personer fortsätter att öka. För att dämpa buller används ofta höga och breda bullerskärmar, vilket inte är att föredra i urban miljö. Ny forskning undersöker därför andra alternativ, bland annat hur växter och gröna områden kan verka bullerreducerande. Forskare menar att växter med hjälp av sina stammar, bladverk och substratet de står i kan reducera ljud genom reflektion, absorption och spridning av ljudenergin. Detta examensarbete syftade till att utvärdera olika växtelement ur bullerreducerande synpunkt. Växters bullerreducerande förmåga är något varken akustiker eller landskapsarkitekter generellt sett tar hänsyn till och därför ansågs en kunskapssammanställning ligga i tiden. För att göra detta har en litteraturstudie, två intervjuer samt mätningar på två växtelement utförts. Mätningarna gjordes på häckar längs Luthagsesplanaden i Uppsala och på en fasad med klätterväxter på Norr Mälarstrand i Stockholm. Litteratur- och intervjustudien visade att växtbeklädda bullerbarriärer hade högst potential att reducera buller längs vägar, gröna tak högst potential att reducera buller in på innergårdar och gröna fasader högst potential att dämpa buller på torg. Växter har också möjlighet att osynliggöra ljudkällor, vilket gör att vi upplever ljudet som lägre. Mätningarna visade att häcken på Luthagsesplanaden hade möjlighet att dämpa ljudet precis bakom häcken med upp till 3 decibel (dBA). Minskningen höll sig inte ända in till fasaden vilket tros bero på att det reflekterade ljudet dominerar i gaturummet samt att den avskärmande effekten minskar med ökat avstånd. Höga frekvenser dämpades bäst av häcken med den högsta dämpningen på 18 dBA för frekvensbandet 16000 Hz. Dämpningen av de höga frekvenserna syns även in vid fasaden med en dämpning kring 4-5 dBA. Häcken efterliknades i modelleringsprogrammet CadnaA med den nordiska beräkningsmodellen för vägtrafikbuller, men inget objekt tycktes kunna representera häcken på ett reproducerbart sätt. På Norr Mälarstrand visades ingen signifikant skillnad i varken ljudtrycksnivå eller frekvensfördelning från fasaden med klätterväxter. En dämpning på upp till 4 dBA för frekvenser över 800 Hz kan dock antydas in vid fasaden. Vid modellering av fasaden visades att varken en reflekterande eller en absorberande fasad kunde representera klätterväxterna. / Traffic noise is the environmental problem that affects most people in Sweden. Studies show that noise can affect human health by causing hearing damage, stress, insomnia and cardiovascular disease. Swedish cities today are built increasingly close, increasing the number of people that are affected by noise. Today, the most common way to reduce noise is to use barriers. In towns, this is not preferable and new research brings up other suggestions that can fit into an urban environment. Some studies are investigating how plants can reduce noise. Research has shown that plants by their trunks, foliage and substrate can reduce sound by reflection, absorption and diffusion. This thesis aimed to identify and evaluate various plant elements through a noise abatement perspective. This perspective is something neither acoustician nor landscape architects in general takes into account and was therefore considered useful. To do this, a literature study, two interviews and measurements were made. The measurements were made on hedges along Luthagsesplanaden in Uppsala and on a facade with climbing plants on Norr Mälarstrand in Stockholm. The literature and the interviews showed that vegetated noise barriers had the highest potential to reduce noise along roads, green roofs had the maximum potential to reduce noise in courtyards and green facades had the maximum potential to reduce noise in squares. Plants are also able to hide sound sources, enabling us to perceive the sound as lower. The measurements showed that the hedge were able to lower the sound pressure level up to 3 decibels (dBA). This reduction did not last to the facade, which is believed to be due to reflected sound dominating the street canyon and that the shielding ability decreases with increasing distance. The hedge was able to lower the higher frequencies the most with the maximum attenuation of 18 dBA for the frequency 16000 Hz. The attenuation of high frequencies is also visible close by the facade with attenuation around 4-5 dBA. The hedge were imitated by different elements in the sound modeling program CadnaA with the help of the Nordic calculation model for road traffic noise, but no element seemed to be able to represent the hedge. The measurement at Norr Mälarstrand showed no significant difference in either sound pressure level or frequency distribution by the facade with climbing plants. However, a damping of up to 4 dBA for frequencies above 800 Hz could be hinted from the measurement by the facade. When modeling the same it was shown that neither an absorbing facade nor a reflecting facade could represent the facade with climbing plants.

Le bruit engendré par le trafic routier est aujourd'hui une des nuisances sonores d'origine anthropique les plus importantes en milieu terrestre. Cette thèse, à l'interface entre comportement et écophysiologie, a eu pour but de déterminer expérimentalement les impacts d'une exposition à du bruit de trafic routier tant sur les systèmes de communication (acoustique et visuelle) que sur la physiologie (stress, immunité…) animale. Le choix de Hyla arborea, espèce utilisant à la fois des signaux acoustiques et colorés pour la communication, nous a permis de tester efficacement nos différentes hypothèses. Alors que chez de nombreuses espèces d'oiseaux des modifications du système de communication acoustique ont été observées (tant chez l'émetteur que le récepteur), mes travaux n'ont pas mis en évidence de telles perturbations chez Hyla arborea. Cependant, et pour la première fois, j'ai pu mettre en évidence un impact du bruit de trafic routier sur la communication visuelle, une exposition chronique à du bruit de trafic routier entraînant une perte de couleur chez les mâles. Enfin, des mesures physiologiques m'ont permis de montrer qu'une exposition chronique à du bruit de trafic routier est stressant (élévation du niveau de corticostérone) et a un effet immunosuppresseur (dû à l'augmentation du stress) chez H.arborea. Ainsi cette thèse démontre que le bruit de trafic routier peut avoir un impact plus large que ce qui était suggéré jusqu'à présent en impactant, en plus de la communication acoustique, la communication visuelle (signaux colorés) et la physiologie des animaux / Road traffic noise is undoubtedly the most important source of anthropogenic noise on terrestrial habitat. This thesis, at the interface between behaviour and physiology was designed to experimentally determine the impacts of road traffic noise exposure on both animal communication systems (acoustic and visual) and physiology (stress, immunity ...) The choice of Hyla arborea, species using both acoustic and coloured signals for communication, allowed us to efficiently test our various hypotheses. While in many bird species changes in acoustic communication system have been observed (in both the transmitter and receiver) my results do not show such disturbances in H. arborea. However, for the first time, I was able to highlight the impact of road traffic noise on visual communication, chronic exposure to traffic noise resulting in colouration loss in male. In addition, physiological measures have allowed me to show that road traffic noise exposure is stressful (corticosterone level rise) and has immunosuppressive effect (due stress rise) in H.arborea. Thus, this thesis demonstrates that road traffic noise may have a larger effect than previously thought by impacting, in addition to the acoustic communication, visual communication (impact on coloured signals) and animal physiology