| 1. |
- Botteldooren, Dick, et al.
(författare)
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An LAeq is not an LAeq.
- 2005
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Ingår i: Journal of the Acoustical Society of America. - 0001-4966. ; 117:4, s. 2616-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Classical dose response relationships for environmental noise annoyance have been based on Ldn or Lden. These exposure measures are essentially based on an energy averaging measure, LAeq. Differences between groups of sources (e.g., continuous or event based) are accounted for by using separate dose-effect relationships. In society today, one often sees that event loudness is traded for number of events which is perfectly acceptable within the LAeq based annoyance concept. Clearly a more unified theory for noise annoyance is needed to fully account for the effect of such trade-offs. In this paper a model implementing such a theory is presented. The perceptual model starts from the premises that a sound event has to be noticed for it to contribute to overall annoyance. The model accounts for the fact that noticing a noise event not only depends on the level of the event itself but also on background noise, sound insulation and acoustic characteristics of the dwelling, level of attention, etc. The severity of the effect of a noticed sound on overall annoyance is assumed to primarily depend on the signal to noise ratio. The model allows to account for modifiers such as previous exposure, noise sensitivity, and coping. The model results are compared to the findings of a recent field experiment. Conclusions based on calculated and experimental trends are presented.
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| 2. |
- Botteldooren, Dick, et al.
(författare)
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From Sonic Environment to Soundscape
- 2015
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Ingår i: Soundscape and the Built Environment. - Boca Raton : CRC Press. - 9781482226317 - 9781482226324 ; , s. 17-41
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Bokkapitel (refereegranskat)
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| 3. |
- De Coensel, B., et al.
(författare)
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A computational model for auditory saliency of environmental sound
- 2009
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America. - 0001-4966 .- 1520-8524. ; 125:4 (part2), s. 2528-2528
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Tidskriftsartikel (refereegranskat)abstract
- Because the information flow received by the human auditory system exceeds the processing capacity of the brain, neural mechanisms engage and guide attention toward prominent parts of the auditory scene. Several computational models for auditory saliency have been proposed recently. Most of these are concerned with speech recognition, and therefore apply high temporal and spectral precision to relatively short sound fragments. Here, a simplified model is described that specifically targets the long exposure times usually considered in soundscape research. The model trades temporal and spectra accuracy for computational speed, but nevertheless implements the key elements that are present in the calculation of complex auditory saliency maps. A simplified “cochleagram” is calculated from the 1/3-octave band spectrogram using the Zwicker model for specific loudness. Saliency is determined based on spectro-temporal irregularities, extracted in parallel at different feature scales, using a center-surround mechanism. Finally, conspicuous peaks are selected using within-feature and between-feature competitions. The model is shown to behave as expected for a number of typical sounds. As an illustration, saliency calculation results for a set of recordings in urban parks are compared with other acoustical descriptors and with perceptual attribute scales from questionnaire studies.
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| 4. |
- De Coensel, Bert, et al.
(författare)
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A model for the perception of environmental sound based on notice-events
- 2009
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America. - 0001-4966 .- 1520-8524. ; 126:2, s. 656-665
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Tidskriftsartikel (refereegranskat)abstract
- Anapproach is proposed to shed light on the mechanisms underlyinghuman perception of environmental sound that intrudes in everyday living.Most research on exposure-effect relationships aims at relating overall effectsto overall exposure indicators in an epidemiological fashion, without includingavailable knowledge on the possible underlying mechanisms. Here, it isproposed to start from available knowledge on audition and perceptionto construct a computational framework for the effect of environmentalsound on individuals. Obviously, at the individual level additional mechanisms(inter-sensory, attentional, cognitive, emotional) play a role in the perceptionof environmental sound. As a first step, current knowledge ismade explicit by building a model mimicking some aspects ofhuman auditory perception. This model is grounded in the hypothesisthat long-term perception of environmental sound is determined primarily byshort notice-events. The applicability of the notice-event model is illustratedby simulating a synthetic population exposed to typical Flemish environmentalnoise. From these simulation results, it is demonstrated that thenotice-event model is able to mimic the differences between theannoyance caused by road traffic noise exposure and railway trafficnoise exposure that are also observed empirically in other studiesand thus could provide an explanation for these differences.
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| 5. |
- De coensel, Bert, et al.
(författare)
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Soundscape classifying ants
- 2007
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Ingår i: Proc. Inter-Noise 2007. ; , s. Paper IN07–431-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 6. |
- de Kluizenaar, Yvonne, et al.
(författare)
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Annoyance and disturbed sleep due to road traffic noise: The importance of the least exposed side - QSIDE
- 2013
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Ingår i: The 42nd International Congress and Exposition on Noise Control Engineering Inter-Noise 2013, 15-18 September, Innsbruck, Austria.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: In urban areas, road traffic noise is a dominant source of environmental noise and a major cause of noise annoyance and disturbed sleep. It has been hypothesized that respondents highly exposed to noise at multiple sides of their dwelling, may be expected to be worse off than respondents with the same exposure at the most exposed side, but also having a quiet side to their dwelling. Previous studies provide support for this hypothesis, however to date only a limited number of studies have investigated this hypothesis. There is a need for strengthening existing evidence, and for further quantification of the effects. Methods: Within the EU project QSIDE, the effect of the least exposed facade on annoyance and sleep response is studied in different EU cities in Sweden, Belgium and the Netherlands, including Gothenburg, Stockholm, Antwerp, Gent and Amsterdam. Results: In this paper we discuss the general picture arising from the outcome of these studies. We discuss what the implications may be for new situations (urban planning) and existing high exposure situations (noise abatement measures). Conclusion: The noise environment may be improved by taking into account the exposure levels, and promoting quietness, at the least exposed façade.
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| 7. |
- Forssén, Jens, et al.
(författare)
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A model of sound scattering by atmospheric turbulence for use in noise mapping calculations
- 2014
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Ingår i: Acta Acoustica united with Acustica. - : S. Hirzel Verlag. - 1610-1928 .- 1861-9959. ; 100:5, s. 810-815
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Tidskriftsartikel (refereegranskat)abstract
- Sound scattering due to atmospheric turbulence limits the noise reduction in shielded areas. An engineering model is presented, aimed to predict the scattered level for general noise mapping purposes including sound propagation between urban canyons. Energy based single scattering for homogeneous and isotropic turbulence following the Kolmogorov model is assumed as a starting point and a saturation based on the von Kármán model is used as a first-order multiple scattering approximation. For a single shielding obstacle the scattering model is used to calculate a large dataset as function of the effective height of the shielding obstacle and its distances to source and receiver. A parameterisation of the dataset is used when calculating the influence of single or double canyons, including standardised air attenuation rates as well as façade absorption and Fresnel weighting of the multiple façade reflections. Assuming a single point source, an aver aging over three receiver positions and that each ground reflection causes energy doubling, the final engineering model is formulated as a scattered level for a shielding building without canyon plus a correction term for the effect of a single or a double canyon, assuming a flat rooftop of the shielding building. Input parameters are, in addition to geometry and sound frequency, the strengths of velocity and temperature turbulence.
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| 8. |
- Forssén, Jens, 1968, et al.
(författare)
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Toolbox from the EC FP7 HOSANNA project for the reduction of road and rail traffic noise in the outdoor environment
- 2014
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Ingår i: Transport Research Arena 2014, Paris, France. ; , s. 10-
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Konferensbidrag (refereegranskat)abstract
- This paper offers a brief overview of innovative methods for road and rail traffic noise reduction between sourceand receiver. These include using new barrier designs, planting of trees, treatments of ground and road surfacesand greening of building façades and roofs using natural materials, like vegetation, soil and other substrates incombination with recycled materials and artificial elements. The abatements are assessed in terms of numericallypredicted sound level reductions, perceptual effects and cost–benefit analysis. Useful reductions of noise fromurban roads and tramways are predicted for 1-m-high urban noise barriers and these are increased by addinginter-lane barriers. A 3 m wide 0.3 m high lattice ground treatment, a carefully planted 15-m-wide tree belt andreplacing 50 m of paved areas by grassland are predicted to give similar reductions. Tree belts are shown to bevery cost-effective and combining tall barriers with a row of trees reduces the negative impact of wind. Greenroofs may significantly reduce the noise at the quiet side of buildings.
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| 9. |
- Forssén, Jens, 1968, et al.
(författare)
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Åtgärder i utomhusmiljön för att minska buller från väg- och tågtrafik – resultat från EU-projektet HOSANNA
- 2013
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Ingår i: LjudBladet, Svenska akustiska sällskapet. - 1403-2317. ; 3, s. 16-28
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Denna artikel ger en kort översikt av bulleråtgärder, resulterande från EU-projektet HOSANNA, för minskning av buller från väg- och spårtrafik under ljudets utbredning. Dessa verktyg inkluderar användning av ny skärmdesign, plantering av träd, förbättringar av mark- och vägytor samt vegetation på byggnadsfasader och tak, med hjälp av naturmaterial, såsom vegetation, jord och andra substrat i kombination med återvunnet material och artificiella element. De akustiska insättningsdämpningarna bedöms genom numeriska beräkningar, perceptuella effekter och kostnadsnyttoanalys. En betydande minskning av buller från väg- och spårtrafik förutsägs för ett 1-m-högt urbant bullerskydd. Detta kan förbättras, upp till ca 10 dB insättningsdämpning, genom att placera ytterligare skydd mellan körfälten. Ett 3 m brett och 0,3 m högt rutnät, ett omsorgsfullt planterat 15 m brett trädbälte samt att ersätta 50 meter asfalterad mark med gräsmark förutspås ge bullerminskningar om 5–8 dB, medan användning av fasadvegetation och gröna tak kan minska nivån på innergårdar med upp till ca 4 respektive 7 dB. Trädbälten visar sig vara mycket kostnadseffektiva och kombinationer av höga skärmar med en rad av träd minskar de negativa effekterna av vind på bullerskärmars insättningsdämpning. Gröna tak kan minska bullret på den tysta sidan av byggnader.
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| 10. |
- Hornikx, Maarten, 1980, et al.
(författare)
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Modelling of scattering of sound from trees by the PSTD method
- 2011
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Ingår i: Forum Acusticum, Aalborg, Denmark. ; , s. 6-
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Konferensbidrag (refereegranskat)abstract
- In an urban environment with multiple building façade reflections, scattering from trees will increase the diffusivity of the sound field and can lead to a reduction of the noise level. Here, the possibility to incorporate scattering objects as the trunk and branches of trees in the framework of an urban propagation model, the Fourier pseudospectral time-domain (PSTD) method, has been investigated. Two different modelling approaches are studied, with either a different density of the scattering objects or with the acoustic normal velocity components at the scattering boundaries and all acoustic components inside the scattering volumes equal to zero. The first PSTD scattering approach shows to work best, although some underestimation of levels is shown. The accuracy of modelling scattering from trees by using a coarser mesh is investigated.
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