Tourist Influence on Nightlife Noise

Although environmental noise from entertainment and leisure activities is causing a growing number of complaints from EU population, this noise issue is not covered by the current EU initiatives on environmental noise management. This noise problem is difficult to tackle strategically and technically – no specific standards have yet been established for measurements, methods and indicators, and the practical remedies are still limited. This paper reviews nightlife noise and more specifically how the presence of tourists influences the variation of the noise. Several case studies were conducted in some Spanish locations by the seasonal tourist incursion, mainly in the summer months. Variations in the nightlife noise in recreational zones during the weekends and “working days” are compared. This research also discusses data from different years and seasonal periods and reinforced with data obtained through surveys specifically designed for foreign tourists. These surveys reveal practical information about how tourists perceive noise, and their behaviour and reactions to it. Those data could be useful for Environmental Noise Authorities to develop noise action plans, as recreational noise is a source not considered when noise mapping by means of using simulation techniques

Noisy Environments: the Influence on Basic Cognitive Processes

The attention processes in people is affected by background noise produced by many different sources. Beta (13-30Hz) and Theta (4-7 Hz) waves are directly related to attention and memory processes. Volunteers were asked to perform an attention test with and without background noise and their cerebral activity was recorded through electroencephalography (EEG). Results shows significant decreases in both beta and theta frequency bands (beta 13-30 Hz and theta 4-7 Hz) under background noise exposure. The attentional improvement is related to increases of the beta and theta waves, and we have observed that those decreases are directly related to a lack of attention caused by the exposure to background noise

Spatial Interpolation contribution to noise maps uncertainty

Noise maps results are usually presented as contour graphs or isophone curves, which describe the sound levels as functions of spatial location. These maps are added to Geographic Information Systems (GIS), allowing sound level evaluation as a function of the continuous coordinates x and y, for a given height above ground. Although the outcome of the system is a continuous variable, the calculations that allow its evaluation are obtained in discrete points that form a calculation grid, which is created by the application of spatial sampling techniques. Using spatial interpolation tools, values are assigned to the locations in which measures or calculations have not been performed. The application of sampling and interpolation techniques (the type of grid, its density, the interpolation algorithms…) contributes to the uncertainty of the results. This paper describes a calculation method to quantify the uncertainty associated to the spatial sampling and interpolation process. We also propose a revision of the classical meaning of noise mapping uncertainty, taking into account the final application of the results

Influencia del ruido de fondo en ambientes universitarios sobre los procesos cognitivos básicos

En este trabajo, se presenta un estudio cuyo objetivo fue determinar la influencia del ruido de fondo producido dentro de instalaciones universitarias sobre procesos cognitivos básicos tales como: la percepción y la atención. Se realizaron grabaciones de ruido de fondo en aulas de clase, bibliotecas, etc., para luego exponer a estudiantes universitarios a estos ambientes sonoros. Se registró la actividad cerebral a través de electroencefalografías (EEG), estudiando los cambios en las bandas de frecuencia relacionadas con procesos atencionales (beta 13-30 Hz. y theta 4-7 Hz.). Los resultados preliminares aquí presentados, muestran un decremento en estas bandas al exponer a los voluntarios a ruido de fondo. Así mismo, se aplicó una prueba psicométrica para determinar cambios en la atención. Los resultados obtenidos en esta prueba, no permiten relacionar directamente la influencia del ruido de fondo sobre los procesos atencionales

Preliminary test to characterize the soundscape of the Plaza Mayor in Madrid

This paper is a first step of a research about the analysis of the richness of the existing sounds in the Plaza Mayor, due to the old and traditional shops and bars under its porticoes together with the huge daily affluence of people. In this paper we study the sound preferences of the salesmen and bar tenders at those traditional shops. These sound preferences include particular sounds, time of occurrence and date of specific annoying and pleasant sounds perceived at the square and the shops surrounding it. To carry out this study, several noise level measurements and socio-acoustic surveys were held. We will also try to correlate sound preferences and annoyance with noise levels of specific events existing at this particular square

Reduction in Calculated Uncertainty of a Noise Map by Improving the Traffic Model Data Through Two Phases

The influence of applying European default traffic values to the making of a noise map was evaluated in a typical environment like Palma de Mallorca. To assess these default traffic values, a first model has been created and compared with measured noise levels. Subsequently a second traffic model, improving the input data used for the first one, has been created and validated according to the deviations. Different methodologies were also examined for collecting model input data that would be of higher quality, by analysing the improvement generated in the reduction in the uncertainty of the noise map introduced by the road traffic noise emissio

Mejora de los datos de entrada en la realización de un mapa de ruido y sus efectos en la incertidumbre

Debido a la existencia de recomendaciones europeas que establecen valores por defecto ante la ausencia de datos en el proceso de realización de un mapa de ruido [1], se ha evaluado la influencia de aplicar dichos valores en un caso concreto como es el mapa estratégico de ruido de Palma de Mallorca. Se compararon los resultados de la simulación tras aplicar dichos valores por defecto con niveles de ruido obtenidos mediante medidas experimentales y se analizaron las desviaciones para determinar la calidad del modelo. Después de obtener un primer resultado de calidad inaceptable, se ha cuantificado la mejora de los resultados tras la utilización de datos de entrada de mayor calidad al modelo acústico. Este análisis demuestra que el uso de datos por defecto, en ausencia de datos de entrada de mayor calidad, genera unos resultados con desviaciones superiores a los 9 dB. Consecuentemente, se obtuvieron nuevos datos de entrada al modelo con mayor calidad, analizando su efecto en la reducción de la incertidumbre del resultado final del mapa de ruido. El proceso de obtención de dichos datos consistió en el desarrollo de una actualización de los datos de tráfico con mayor número de datos de flujo; la implementación de una nueva categorización viaria; y la utilización de técnicas novedosas para la adquisición de composición y velocidad de tráfic

Improvement of the Quality of Input Data and its Effect in the Uncertainty of a Noise Map

The influence of applying European default values to the making of a noise map was evaluated in a typical environment like Palma de Mallorca. These default values were compared with measured noise levels and the model was validated or rejected according to the deviations. After an unacceptable initial result, quantification of improvements to the process has been performed. This analysis demonstrates that the use of noise source default data in the absence of specific data can generate deviations in excess of more than 9 dB. Consequently, additional data gathered were of higher quality and were collected using different techniques. Different methodologies were also examined for collecting model input data that would be of the highest possible quality, by analysing the improvement generated in the reduction in the uncertainty of the final result of the noise map. Improvements to the process consisted of a developing a new traffic network with current data, obtaining more experimental data with a greater geographical sampling of traffic, implementing a new road categorization system and using alternative techniques to obtain the composition and speed of traffic

Study of Uncertainty in Noise Mapping

Noise mapping is a complex process requiring a large amount of data from different sources, which are not always available. In the process, there are many factors involving simplifications, approaches and deviations that contribute to the final uncertainty of the result. An error in the final result of the noise map causes an incorrect amount of exposed population, as well as the design and implementation of inadequate or wrong noise action plans. The uncertainty analysis in the creation of noise maps is therefore a key tool to design noise action plans. However, up to now, there are only guides giving an approximate range of possible contribution to the uncertainty depending on the quality of input data. The present paper analyses the contributions to the total uncertainty of a noise map, proposing a methodology to quantify it. After analyzing the sources that contribute to the overall system uncertainty, a method to quantify the expanded uncertainty properly is proposed, through an analytical calculation and experimental determination. Thus, a specific value of the uncertainty of a map can be calculated avoiding approximations and range values

Self-Adaptive Grids for Noise Mapping

Often, the quality of the results in a noise map is expressed as a comparison between measured and calculated noise levels at several sample locations spread over the map. Although, under some circumstances this could be considered as a valid approximation, it excludes from the noise mapping process two very important stages: interpolation and classification. The two tasks must be applied to obtain a full map, with contours and isolines that allow characterizing the noise levels at every location in it.The grid of receivers used for calculations has an influence in the final results. We could summarize that, the thinner the grid (more receivers), the better the results. As the receivers’ density increases, the accuracy of the map is improved, but the computational costs will also increase exponentially. Furthermore, most of the receivers do not contribute to the optimization of the map quality.The main objective of this paper is to present a method that substantially improves the quality of a map at its isolines by using self-adaptive grids.Self-adaptive grids are created using a smart iterative algorithm that analyses previous knowledge to concentrate the calculation effort in those areas where it will be more effective. Because of this, it can provide better results than higher resolutions grids, while using fewer receivers for calculation and interpolation.Self-adaptive grids improve the results obtained by any starting grid, no matter the resolution of the grid, the interpolation method (idw, spline, kriging,..), the number of receivers, or the way they have been located (random, triangulated or equal spaced). As further knowledge (extra receivers) is provided as in input to the interpolator, the results will be improved.Self-adaptive grids have been proven to be an excellent method especially for open spaces with few obstacles. The use of a coarse initial grids, allow the number of calculated receivers to be reduced enormously, while improving the accuracy of the map. The calculation time is drastically reduced, as the number of calculation receivers is reduced. Because of this reason, this method may be very useful for grid refinement in models that do not consider obstacles in propagation paths (for instance, Integrated Noise Mapping, INM, for airports noise mapping