994 resultados para Traffic Noise


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Invasive species can disrupt the communication systems that native biota use for reproductive interactions. In tropical Australia, invasive cane toads (Rhinella marina) breed in many of the same waterbodies that are used by native frogs, and males of both the invader and the native taxa rely on vocal signals to attract mates. We conducted playback experiments to test the hypothesis that calls of toads may influence the calling behaviour of frogs (Limnodynastes convexiusculus and Litoria rothii). Male L. convexiusculus adjusted their calling rate and the variance in inter-call interval in response to a variety of sounds, including the calls of cane toads as well as those of other native frog species, and other anthropogenic noise, whereas L. rothii did not. Within the stimulus periods of playbacks, male L. convexiusculus called more intensely during long silent gaps than during calling blocks. Thus, males of one frog species reduced their calling rate, possibly to minimise energy expenditure during periods of acoustic interference generated by cane toads. In spite of such modifications, the number of overlapping calls (within stimulus periods) did not differ significantly from that expected by chance. In natural conditions, the calls of cane toads are continuous rather than episodic, leaving fewer gaps of silence that male frogs could exploit. Future work could usefully quantify the magnitude of temporal (e.g. diel and seasonal) and spatial overlap between calling by toads and by frogs and the impact of call-structure shifts on the ability of male frogs to attract receptive females.

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No Brasil, é grande o número de casas e apartamentos que sofrem a influência da poluição sonora. Atualmente, esta questão ganhou importante destaque no cenário local, uma vez que Belém-PA foi eleita a “Capital Nacional do Ruído” por vários anos, segundo dados obtidos pelo IBGE. Dentre os tipos mais comuns de poluição sonora, percebe-se que há uma maior queixa por parte da sociedade em relação ao c, o qual é inerente ao cotidiano de qualquer grande cidade. À medida que os problemas de ruído de tráfego aumentam, cresce a preocupação com o grau de incômodo gerado na população, justificando o desenvolvimento de meios para quantificar e reduzir tal desconforto, além da busca por uma regulamentação desta situação, através de normas brasileiras. Portanto, a condição do ruído de tráfego, enquanto principal agente de incômodo da população, no que se refere à poluição sonora, vem justificar a necessidade de realização de um estudo que vise o desenvolvimento de elementos de edificações, de novas geometrias e de composição de materiais existentes, tais que se minimize a penetração do ruído de tráfego aos ambientes internos dessas edificações. Assim, este trabalho apresenta os resultados de estudos do comportamento acústico em edificações situadas frontalmente às vias de grande fluxo de veículos e que sofrem interferências ocasionadas pelo ruído de tráfego gerado em excesso, por essas fontes veiculares. Para tanto, foram realizadas medições em campo numa edificação de 25 andares, em fase avançada de construção e escolhida como piloto para o presente estudo, o qual apresenta uma modelagem numérica da edificação modelo, com o auxílio do software ODEON.

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Invasive species are known to affect native species in a variety of ways, but the effect of acoustic invaders has not been examined previously. We simulated an invasion of the acoustic niche by exposing calling native male white-banded tree frogs (Hypsiboas albomarginatus) to recorded invasive American bullfrog (Lithobates catesbeianus) calls. In response, tree frogs immediately shifted calls to significantly higher frequencies. In the post-stimulus period, they continued to use higher frequencies while also decreasing signal duration. Acoustic signals are the primary basis of mate selection in many anurans, suggesting that such changes could negatively affect the reproductive success of native species. The effects of bullfrog vocalizations on acoustic communities are expected to be especially severe due to their broad frequency band, which masks the calls of multiple species simultaneously.

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Nella tesi si analizzano le principali fonti del rumore aeronautico, lo stato dell'arte dal punto di vista normativo, tecnologico e procedurale. Si analizza lo stato dell'arte anche riguardo alla classificazione degli aeromobili, proponendo un nuovo indice prestazionale in alternativa a quello indicato dalla metodologia di certificazione (AC36-ICAO) Allo scopo di diminuire l'impatto acustico degli aeromobili in fase di atterraggio, si analizzano col programma INM i benefici di procedure CDA a 3° rispetto alle procedure tradizionali e, di seguito di procedure CDA ad angoli maggiori in termini di riduzione di lunghezza e di area delle isofoniche SEL85, SEL80 e SEL75.

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In the past centuries and before the invention of automobile, roads consisted mainly of unpaved paths connecting only few cities. Later, in the beginning of the twentieth century, the automobile was introduced and a new type of the transportation system was born. Therefore, it was necessary to change the condition of roads to fit with the automobiles. With the spread and the development of the automobiles, roads also have developed and increased all over the world. That caused negative effects on the environment and humans’ life quality. Thus, highways associations and communities had to take some steps to reduce these effects and care about environmental and cultural issues with the traditional commitment to safety and mobility, and that is known as context sensitive design. The aim of this thesis is to use the concepts of context sensitive design to reduce the negative environmental impacts of provincial road Galliera, which connects via Colombo in city of Bologna to provincial road 3 in Argelato city. Some solutions were proposed in this thesis to reduce traffic noise, fragmentation, fauna mortality and to improve the aesthetics of the road.

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Eco-driving has well-known positive effects on fuel economy and greenhouse-gas emissions. Moreover, eco-driving reduces road-traffic noise, which is a serious threat to the health and well-being of many people. We investigated the psychological predictors of the adoption of eco-driving from the perspective of road-traffic noise abatement. The data came from 890 car drivers who participated in a longitudinal survey over four months. Specifically, we tested the effects of the intention to prevent road-traffic noise, variables derived from the theory of planned behavior (social norm, perceived behavioral control, and attitude), and variables derived from the health action process approach (implementation intention, maintenance self-efficacy, and action control) on the intention to practice eco-driving and on eco-driving behavior. The intention to prevent road-traffic noise was not linked to the intention to practice eco-driving. The strongest predictors of the intention to practice eco-driving were attitude and perceived behavioral control. The strongest predictor of eco-driving behavior was action control. The link between behavioral intention and behavior was weak, indicating that drivers have difficulties putting their intention to practice eco-driving into action. Therefore, intervention efforts should directly address and support the transition from intention to behavior. This could be accomplished by providing reminders, which help to maintain behavioral intention, and by providing behavior feedback, which helps car drivers to monitor their behavior.

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El ruido de tráfico generado en la ciudad es uno de los principales problemas ambientales que afecta notablemente a la calidad de vida de los ciudadanos. Actualmente, la manera de abordar el problema de la contaminación acústica se basa principalmente en medidas correctoras que se aplican a posteriori; cuando el problema ya existe. El problema del ruido debería abordarse además, con medidas preventivas aplicables en la fase de diseño de la ciudad. Sin embargo existen pocos estudios acústicos que puedan aportar conclusiones concretas sobre cómo afectan acústicamente las decisiones tomadas en el planeamiento urbano, ni sobre cómo podrían optimizarse. El trabajo realizado consiste en el estudio de la propagación de ruido en diversas calles representativas de la ciudad de Madrid que pertenecen a diversas tipologías urbanas. De él se concluye que existe una relación directa entre las características tipológicas urbanas y la propagación del ruido. Este estudio representa la base para la investigación acústica sobre múltiples aspectos urbanos y se encuadra en esta nueva área de investigación dentro de la acústica, que podría estar al servicio del planeamiento urbanístico, aportándole las herramientas que precisa para optimizar el diseño de las ciudades teniendo en consideración la problemática del ruido. ABSTRACT. Traffic noise generated in the city has become one of the main environmental problems that significantly affects the quality of life of its citizens. Currently, the approach to the problem of acoustic noise pollution is mainly based on corrective methods that are applied retrospectively; when the problem already exists. The problem of noise pollution in the city should also be dealt with preventive methods, developed in the design phase of the city. However there are few studies that can provide concrete conclusions on how urban planning decisions can affect acoustically the noise problem, or how to optimize it. This work consists in studying noise propagation in several representative streets in the city of Madrid. These streets are a selection belonging to different urban typologies. This study reveals that a direct relation exists between the urban typological characteristics and the noise propagation. This conclusion represents the base for acoustic research on multiple urban aspects. The work fits into this new area of research in acoustics, which could be at the service of the urban planning, giving it the tools it needs to improve urban designing taking into account the problem of noise.

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El objetivo del trabajo es estudiar el procedimiento descrito en el proyecto IMAGINE(estimación del nivel de ruido del tráfico rodado que se registra en las carreteras europeas, a partir de la obtención del nivel de potencia sonora del ruido de propulsión y del ruido de rodadura). Para validar el modelo, se compararán los resultados teóricos del proyecto con los niveles registrados en las inmediaciones de la M-40, dentro del campus de la Escuela Universitaria de Ingeniería Técnica de Telecomunicación. Para obtener los valores reales, además de lo descrito en el proyecto IMAGINE se empleará como método de medida el descrito en la ISO 1996- Parte 2 y con el instrumental con el que cuenta la Escuela. SUMMARY. The objective of this work is to analyse the procedure described in the IMAGINE project(estimation of the road traffic noise level that can be observed in the European roads, by means of obtaining the level of audible power from both the propulsion and rolling noise), in order to validate the model. The theoretical results from the project will be compared against the levels measured in the surroundings of the M-40 in Madrid, within the campus of the Escuela Universitaria de Ingeniería Técnica de Telecomunicación. To obtain the real values, the IMAGINE project and the methodology described in the norm ISO 1996 - Part 2 will be used, with the equipment made available by the Faculty.

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El ruido derivado de las actividades de ocio es uno de los contaminantes acústicos más importantes en la sociedad actual. Este foco de ruido no sólo se encuentra presente en los entorno de los bares, pubs o discotecas, sino también en las zonas donde se desarrollan los eventos festivos de la ciudad. Sin embargo, son pocos los estudios y actuaciones llevadas a cabo desde el punto de vista ambiental que permitan conocer las principales características del ruido de ocio, los métodos de medida o los parámetros más adecuados. Por este motivo, se han fijado en estos aspectos los objetivos de esta tesis doctoral. Para el estudio del ruido de ocio nocturno se ha desarrollado y evaluado un método de medida, basado en la realización de medidas binaurales durante un recorrido y en medidas de larga duración en puntos fijos de las distintas zonas de ocio de Madrid y Cuenca. A partir de los resultados obtenidos, se ha realizado una caracterización acústica del ruido ocio, se ha definido un procedimiento de actuación en el que se incluye un modelo de predicción, y se ha desarrollado un modelo clasificador capaz de diferenciar el ruido de ocio del ruido de tráfico rodado. En el caso de los eventos de ocio también se ha desarrollado un método de evaluación y medida adaptado a sus características, con el que se han medido los eventos más importantes acontecidos durante un año en Madrid y Cuenca, del análisis de estas medidas se ha determinado qué eventos son los más ruidosos, así como sus características principales y las diferencias entre ellos. Este estudio pretende servir de apoyo en la gestión del ruido ambiental derivado de las actividades de ocio, presentando datos cualitativos y cuantitativos de este tipo de ruido en sus distintas facetas y aportando nuevas herramientas que faciliten su gestión. ABSTRACT Leisure noise is one of the most important environmental pollutants nowadays. This noise is not only nearby leisure venues where people go at night, but also around leisure events like popular parties or concerts placed in urban areas. There are few studies and actions about leisure noise from the environmental noise point of view, and consequently, there are no information about the leisure noise characteristics, the most appropriate measurement methods or the most interesting parameters to evaluate this kind of noise. Consequently, these are the aims of this PhD thesis. About the noise around leisure venues, a measurement method has been defined by using the Soundwalker technique. Besides, fixed point measurements have been done in different leisure areas. With the results of these measurements, a noise characterization has been done and a guide has been developed to act in case of leisure noise problems, including a method to predict the leisure noise in this kind of areas. As well as that, a classifying model has been done to differenciate leisure noise and road traffic noise. A measurement procedure has been developed in the leisure events case. Following this procedure, the most important events happened during a year in two different cities have been measured. With these results, the noisiest events, the most important characteristics of each kind of event and the differences between them have been pointed out. This study tries to support the environmental noise management in the leisure noise case. It provides cualitative and quantitative data of leisure noise levels in different situations; it also defines an action protocol to resolve leisure noise problems and it defines new tools to manage this kind of noise.

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En los últimos años, debido a la creciente preocupación por el calentamiento global y el cambio climático, uno de los retos más importantes a los que se enfrenta nuestra sociedad es el uso eficiente y económico de energía así como la necesidad correspondiente de reducir los gases de efecto invernadero (GEI). Las tecnologías de mezclas semicalientes se han convertido en un nuevo e importante tema de investigación en el campo de los materiales para pavimentos ya que ofrece una solución potencial para la reducción del consumo energético y las emisiones de GEI durante la producción y puesta en obra de las mezclas bituminosas. Por otro lado, los pavimentos que contienen polvo de caucho procedente de neumático fuera de uso, al hacer uso productos de desecho, ahorran energía y recursos naturales. Estos pavimentos ofrecen una resistencia mejorada a la formación de roderas, a la fatiga y a la fisuración térmica, reducen los costes de mantenimiento y el ruido del tráfico así como prolongan la vida útil del pavimento. Sin embargo, estas mezclas presentan un importante inconveniente: la temperatura de fabricación se debe aumentar en comparación con las mezclas asfálticas convencionales, ya que la incorporación de caucho aumenta la viscosidad del ligante y, por lo tanto, se producen mayores cantidades de emisiones de GEI. En la presente Tesis, la tecnología de mezclas semicalientes con aditivos orgánicos (Sasobit, Asphaltan A, Asphaltan B, Licomont) se incorporó a la de betunes de alta viscosidad modificados con caucho (15% y 20% de caucho) con la finalidad de dar una solución a los inconvenientes de mezclas con caucho gracias a la utilización de aditivos reductores de la viscosidad. Para este fin, se estudió si sería posible obtener una producción más sostenible de mezclas con betunes de alto contenido en caucho sin afectar significativamente su nivel de rendimiento mecánico. La metodología aplicada para evaluar y comparar las características de las mezclas consistió en la realización de una serie de ensayos de laboratorio para betunes y mezclas con caucho y con aditivos de mezclas semicalientes y de un análisis del ciclo de vida híbrido de la producción de mezclas semicalientes teniendo en cuenta la papel del aditivo en la cadena de suministro con el fin de cuantificar con precisión los beneficios de esta tecnología. Los resultados del estudio indicaron que la incorporación de los aditivos permite reducir la viscosidad de los ligantes y, en consecuencia, las temperaturas de producción y de compactación de las mezclas. Por otro lado, aunque la adición de caucho mejoró significativamente el comportamiento mecánico de los ligantes a baja temperatura reduciendo la susceptibilidad al fenómeno de fisuración térmica, la adición de las ceras aumentó ligeramente la rigidez. Los resultados del estudio reológico mostraron que la adición de porcentajes crecientes de caucho mejoraban la resistencia del pavimento con respecto a la resistencia a la deformación permanente a altas temperaturas y a la fisuración térmica a bajas temperaturas. Además, se observó que los aditivos mejoran la resistencia a roderas y la elasticidad del pavimento al aumentar el módulo complejo a altas temperaturas y al disminuir del ángulo de fase. Por otra parte, el estudio reológico confirmó que los aditivos estudiados aumentan ligeramente la rigidez a bajas temperaturas. Los ensayos de fluencia llevados a cabo con el reómetro demostraron una vez más la mejora en la elasticidad y en la resistencia a la deformación permanente dada por la adición de las ceras. El estudio de mezclas con caucho y aditivos de mezclas semicalientes llevado a cabo demostró que las temperaturas de producción/compactación se pueden disminuir, que las mezclas no experimentarían escurrimiento, que los aditivos no cambian significativamente la resistencia conservada y que cumplen la sensibilidad al agua exigida. Además, los aditivos aumentaron el módulo de rigidez en algunos casos y mejoraron significativamente la resistencia a la deformación permanente. Asimismo, a excepción de uno de los aditivos, las mezclas con ceras tenían la misma o mayor resistencia a la fatiga en comparación con la mezcla control. Los resultados del análisis de ciclo de vida híbrido mostraron que la tecnología de mezclas semicalientes es capaz de ahorrar significativamente energía y reducir las emisiones de GEI, hasta un 18% y 20% respectivamente, en comparación con las mezclas de control. Sin embargo, en algunos de los casos estudiados, debido a la presencia de la cera, la temperatura de fabricación debe reducirse en un promedio de 8 ºC antes de que los beneficios de la reducción de emisiones y el consumo de combustible puedan ser obtenidos. Los principales sectores contribuyentes a los impactos ambientales generados en la fabricación de mezclas semicalientes fueron el sector de los combustibles, el de la minería y el de la construcción. Due to growing concerns over global warming and climate change in recent years, one of the most important challenges facing our society is the efficient and economic use of energy, and with it, the corresponding need to reduce greenhouse gas (GHG) emissions. The Warm Mix Asphalt (WMA) technology has become an important new research topic in the field of pavement materials as it offers a potential solution for the reduction of energy consumption and GHG emissions during the production and placement of asphalt mixtures. On the other hand, pavements containing crumb-rubber modified (CRM) binders save energy and natural resources by making use of waste products. These pavements offer an improved resistance to rutting, fatigue and thermal cracking; reduce traffic noise and maintenance costs and prolong pavement life. These mixtures, however, present one major drawback: the manufacturing temperature is higher compared to conventional asphalt mixtures as the rubber lends greater viscosity to the binder and, therefore, larger amounts of GHG emissions are produced. In this dissertation the WMA technology with organic additives (Sasobit, Asphaltan A, Asphaltan B and Licomont) was applied to CRM binders (15% and 20% of rubber) in order to offer a solution to the drawbacks of asphalt rubber (AR) mixtures thanks to the use of fluidifying additives. For this purpose, this study sought to determine if a more sustainable production of AR mixtures could be obtained without significantly affecting their level of mechanical performance. The methodology applied in order to evaluate and compare the performance of the mixtures consisted of carrying out several laboratory tests for the CRM binders and AR mixtures with WMA additives (AR-WMA mixtures) and a hybrid input-output-based life cycle assessment (hLCA) of the production of WMA. The results of the study indicated that the incorporation of the organic additives were able to reduce the viscosity of the binders and, consequently, the production and compaction temperatures. On the other hand, although the addition of rubber significantly improved the mechanical behaviour of the binders at low temperatures reducing the susceptibility to thermal cracking phenomena, the addition of the waxes slightly increased the stiffness. Master curves showed that the addition of increasing percentages of rubber improved the resistance of the pavement regarding both resistance to permanent deformation at high temperatures and thermal cracking at low temperatures. In addition, the waxes improved the rutting resistance and the elasticity as they increased the complex modulus at high temperatures and decreased the phase angle. Moreover, master curves also attest that the WMA additives studied increase the stiffness at low temperatures. The creep tests carried out proved once again the improvement in the elasticity and in the resistance to permanent deformation given by the addition of the waxes. The AR-WMA mixtures studied have shown that the production/compaction temperatures can be decreased, that the mixtures would not experience binder drainage, that the additives did not significantly change the retained resistance and fulfilled the water sensitivity required. Furthermore, the additives increased the stiffness modulus in some cases and significantly improved the permanent deformation resistance. Except for one of the additives, the waxes had the same or higher fatigue resistance compared to the control mixture. The results of the hLCA demonstrated that the WMA technology is able to significantly save energy and reduce GHG emissions, up to 18% and 20%, respectively, compared to the control mixtures. However, in some of the case studies, due to the presence of wax, the manufacturing temperature at the asphalt plant must be reduced by an average of 8ºC before the benefits of reduced emissions and fuel usage can be obtained. The results regarding the overall impacts generated using a detailed production layer decomposition indicated that fuel, mining and construction sectors are the main contributors to the environmental impacts of manufacturing WMA mixtures.

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El presente documento, evalúa y analiza el ruido existente en las inmediaciones del CEIS (Centro Estudio, Innovación y Servicios), situado en la carretera Villaviciosa de Odón a Móstoles (M-856) en el Km 1,5. El objetivo es obtener datos de nivel de ruido en función del tiempo para conocer su variabilidad a lo largo de la semana, para promover una intercomparación entre laboratorios con ruido real. La zona que contempla el proyecto tiene variedad de ruido medioambiental: ruido de tráfico rodado, ruido industrial, ruido de instalaciones y ruido de tráfico aéreo. Estas fuentes de ruido pueden presentarse en diversas combinaciones. Para el ruido total existente, se analiza por un lado el ruido específico de la carretera M-856, y por otro lado el ruido residual asociado a sucesos aislados, como el ruido de tráfico aéreo, ruido industrial y de instalaciones. Para el cálculo de los niveles sonoros de la zona se realiza una evaluación del índice de ruido Ld, para el periodo de día, utilizando como herramienta de cálculo el programa CadnaA versión 4.2. Se realiza la validación de los niveles sonoros obtenidos en el CadnaA en las inmediaciones de la carretera Villaviciosa de Odón a Móstoles. Para ello se comparan los niveles obtenidos en el modelo acústico de la zona elaborado mediante CadnaA y los niveles medidos “in-situ”. Una vez obtenidos los niveles sonoros, se calcula la incertidumbre de las medidas ejecutadas “in-situ” en la última jornada de mediciones realizada, correspondientes a niveles de presión sonora continuos equivalente ponderado A (LAeq, 5min) y de las medidas simuladas en CadnaA , teniendo en cuenta las posibles desviaciones ocasionadas por el equipo de medida, condiciones meteorológicas, variaciones del tráfico, metodología de ensayo..... Por último se valoran los datos obtenidos y se evalúa la posibilidad de promover una intercomparación entre laboratorios realizada con el ruido real de tráfico de la zona. ABSTRACT. The next document evaluates the noise in sorrounding areas of CEIS (Centro Estudio, Innovación y Servicios), located in the road from Villaviciosa de Odón to Móstoles (M-856), in 1.5 km. The aim of this project is to get precise information during time to promove an intercomparation between laboratories with real noise. The area included in the project has several environmental noise: traffic noise, industrial noise and air traffic noise. These noise sources can be combined in different ways. The specific noise of the M-856 on one hand, and the residual noise associated with air traffic noise and industrial noise on the other. The calculation tool CadnaA, 4.2 version, simulates sound levels for the day period and the index Ld. The validation of sound levels around the road Villaviciosa de Odon to Móstoles, is made by comparing the obtained levels in the acoustic model and the real measured levels “in situ” . The uncertainty of the measures "in-situ", and the uncertainty of the sound levels simulated in the acoustic model CadnaA, is calculated using the measurements “in situ” (LAeq, 5min) of the last day. For that calculation, is necessary to take into account the deviations resulting from the measurement equipment, weather conditions, traffic variations, test methodology.... Finally the obtained data are evaluated, considering the possibility of promote an intercomparison between laboratories with real traffic noise of the area.

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National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.

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Virginia Department of Highways and Transportation, Richmond

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National Highway Traffic Safety Administration, Office of Passenger Vehicle Research, Washington, D.C.

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Transportation Department, Office of Noise Abatement, Washington, D.C.