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Publications (5)3.29 Total impact

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    ABSTRACT: With the proclamation of the Directive on Environmental Noise (200249), the process of noise mapping and action planning has begun around Europe. Large scale wide area noise modelling requires an extensive range of data inputs. The requirements for these inputs are driven by several factors, including the noise calculation methodologies, noise mapping software system, GIS and the deliverables set out within the Directive and recommended Reporting Mechanism. Utilising a staged approach to project design led to the development of detailed noise mapping data schema specifications prior to the collation of input datasets for the calculation process. The data schema may be used throughout the mapping project as a framework to manage dataset concatenation, data capture or the use of defaults and GPGv2 Toolkits to infill data gaps. They also enable data pre-processing guidelines to be passed to non-acoustic GIS specialists, and help to guide and catalogue data processing steps. This paper presents experience gained whilst developing a number of noise mapping data schema specifications and their implementation within successful projects during the first round of mapping. Railway noise mapping is used as an example of how a data schema may be used to develop solutions to technical problems as well as coordinate data capture.
    The Journal of the Acoustical Society of America 06/2008; 123(5):3263. · 1.65 Impact Factor
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    ABSTRACT: With the proclamation of the Directive on Environmental Noise (200249), the process of noise mapping and action planning has begun around Europe. As the development of strategic noise maps is arguably a new experience for many end-users, the first round of noise mapping could potentially lead to uncertainties within many aspects of the process. Noise maps represent a baseline for the implementation of noise management systems and any systematic errors within the noise maps could reduce the effective implementation of the whole management system. The extensive range of data inputs required in strategic noise mapping are usually obtained from different data sources or base datasets and as such, cataloguing with the use of metadata is key. The implementation of a quality assurance system is imperative to maintain consistency between technicians and within multi-disciplinary teams. It is also essential to ensure the control of processes and the ability to review inputs, intermediaries and deliverables. A similar approach may also be applied to calculation and post processing of noise levels. This paper presents collective experience of the implementation of quality assurance procedures used in several EU countries during the successful completion of projects within the first round of mapping.
    The Journal of the Acoustical Society of America 06/2008; 123(5):3135. · 1.65 Impact Factor
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    ABSTRACT: Noise mapping is an increasingly important method of assessing environmental noise. Noise maps are being generated for projects ranging from small scale new developments with a single noise source to large agglomerations with many noise sources. The largest noise maps require millions of calculations to be carried out and this can lead to long processing times and significant costs for hardware and software. In order to reduce calculation time, noise mapping packages offer efficiency settings which reduce the complexity and numbers of calculations required. Questions over the impact on accuracy and uncertainty of using these efficiency techniques continue to be posed and little objective data has been published about the correlation between calculation speed and accuracy. In addition, the accuracy required from noise maps varies depending on the end use of the data. A noise map required to assess eligibility under the Noise Insulation Regulations for a new road where noise levels are reported to the nearest 0.1 dB will have different requirements to a city wide noise map. These concerns prompted the Department for Environment, Food and Rural Affairs (Defra) to commission research in 2005 on the effect of efficiency techniques on the accuracy of noise levels calculated by mapping software using the United Kingdom road traffic noise prediction methodology – Calculation of Road Traffic Noise (CRTN). Two papers are presented to detail some of the findings from this research. This, the second of the two papers identifies calculation settings available in five noise mapping packages which act as efficiency settings. The research found that for one noise mapping package, effective use of efficiency settings made it possible to reduce calculation time by 99% for an error of 1.09 dB(A).
    01/2006;
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    ABSTRACT: Noise mapping is an increasingly important method of assessing environmental noise. Noise maps are being generated for projects ranging from small scale new developments with a single noise source to large agglomerations with many noise sources. The largest noise maps require millions of calculations to be carried out and this can lead to long processing times and significant costs for hardware and software. In order to reduce calculation time, noise mapping packages offer efficiency settings which reduce the complexity and numbers of calculations required. Questions over the impact on accuracy and uncertainty of using these efficiency techniques continue to be posed and little objective data has been published about the correlation between calculation speed and accuracy. In addition, the accuracy required from noise maps varies depending on the end use of the data. A noise map required to assess eligibility under the Noise Insulation Regulations for a new road where noise levels are reported to the nearest 0.1 dB will have different requirements to a city wide noise map. These concerns prompted the Department for Environment, Food and Rural Affairs (Defra) to commission research in 2005 on the effect of efficiency techniques on the accuracy of noise levels calculated by mapping software using the United Kingdom road traffic noise prediction methodology - Calculation of Road Traffic Noise (CRTN). Two papers are presented to detail some of the findings from this research. This, the first of two papers identifies the most accurate and compliant settings (benchmark settings) for performing CRTN calculations in five different noise mapping packages. Calculation times using benchmark settings ranged from 11.4 seconds to approximately 4,400 seconds per calculation point depending upon the noise mapping software used.
    01/2006;
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    James Trow, Simon Shilton
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    ABSTRACT: Following the publication of the Harmonoise methodologies, research has been carried out investigating the effect of uncertainty in the road traffic source parameters in order to assess the relative significance of each input dataset. Using Monte Carlo Simulations, a series of possible inputs were generated for each source parameter, and the respective emission level calculated, creating a distribution from which the uncertainty in the input could be expressed directly as uncertainty in the decibel emission level. Assessments of the source parameters were conducted both individually and simultaneously. This paper presents the results of this research, and draws parallels between data accuracy and the accuracy of predicted emission levels. It is envisaged this research can aid the design of datasets to increase the quality and reliability of source emission levels.
    01/2005;