Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Entire DC Network
Effects Of Changing The Amount Of Absorption In A Computer Model Of Queen’S Hall, Copenhagen, Denmark, Michelle C Vigeant, Lily M. Wang, Jens Holger Rindel
Effects Of Changing The Amount Of Absorption In A Computer Model Of Queen’S Hall, Copenhagen, Denmark, Michelle C Vigeant, Lily M. Wang, Jens Holger Rindel
Durham School of Architectural Engineering and Construction: Faculty Publications
Room acoustics modelling and auralizations are very useful tools in the design of acoustically sensitive spaces. One area of improvement for auralizations is the method of modelling the source directivity. A new method to incorporate source directivity is multi-channel auralizations. This study first evaluates the objective effects of using four and thirteen channel impulse responses in an ODEON model of Queen’s Hall, where the actual variable absorption is changed within the model. Analyses of the results reveal great differences in the objective parameters of reverberation time and sound pressure level across each channel’s impulse response. Subjective studies were then conducted …
Appropriate Characterization Of Background Noise Levels In The Workplace, Erica E. Bowden, Lily M. Wang
Appropriate Characterization Of Background Noise Levels In The Workplace, Erica E. Bowden, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
Overall loudness is not the only quality of indoor background noise that affects occupants. The distribution of noise across frequency (pitch), whether or not the noise contains tones, and whether or not the noise changes over time must also be considered. There are several indoor noise criteria systems available to quantify the background noise in rooms, but many of them do not account for these factors. These systems are commonly used by architects and engineers, and often incorporated into manufacturer’s data, design guides, and standards. There is much debate over which of the criteria systems best reflect how occupants will …
Room Acoustics In Coupled Volume Spaces, David T. Bradley, Lily M. Wang
Room Acoustics In Coupled Volume Spaces, David T. Bradley, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
The study of sound in the built environment is finding more awareness in the 21st century. As this awareness has increased, and as computing power has grown, the method of computer modeling for studying room acoustics in such settings as classrooms, offices, and performances spaces has taken great strides in recent years. Of particular interest has been the study of the coupled volume space due to its unique ability to provide contrasting acoustical phenomenon. A coupled volume room is generally defined as a space consisting of a large main volume containing high levels of sound absorption connected through small …
Effects Of Noise On Productivity: Does Performance Decrease Over Time?, Jessica Errett, Erica Eileen Bowden, Marc Choiniere, Lily M. Wang
Effects Of Noise On Productivity: Does Performance Decrease Over Time?, Jessica Errett, Erica Eileen Bowden, Marc Choiniere, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
Most people at one time or another have found themselves irritated or distracted by the background noise in a building. The irritation might have resulted in minor aggravation or may have been dramatic enough to hinder their work. This leads us to ask whether occupants are increasingly aggravated by noise the longer they are exposed to it, or if they naturally habituate to their acoustic environment. In an effort to answer this question, a study was completed in the “Indoor Environment Lab” at the University of Nebraska. This lab resembles a typical office and was specially constructed to be acoustically …
A Review Of Diffuse Reflections In Architectural Acoustics, Jonathan Rathsam, Lily M. Wang
A Review Of Diffuse Reflections In Architectural Acoustics, Jonathan Rathsam, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
Diffuse reflections have received increasing attention in architectural acoustics over the past quarter century. The term diffuse refers to non-specular directions. This paper identifies three mechanisms that cause diffuse reflections. Practitioners have found that changing specular reflections into diffuse reflections can reduce noise and echoes both indoors and outdoors. Developers of acoustical modeling software have also found that modeling diffuse in additional to specular reflections produces more accurate predictions. The final portion of this paper presents results for a study of scattering coefficients in acoustical modeling software.
Measuring Sound Power In Ducted Heating, Ventilating, And Air-Conditioning (Hvac) Systems For Use In Verifying Acoustical Prediction Methods, Steven R. Ryherd, Lily M. Wang
Measuring Sound Power In Ducted Heating, Ventilating, And Air-Conditioning (Hvac) Systems For Use In Verifying Acoustical Prediction Methods, Steven R. Ryherd, Lily M. Wang
Durham School of Architectural Engineering and Construction: Faculty Publications
This paper discusses issues regarding in-situ methods of obtaining sound power at a point in a heating, ventilating and air-conditioning (HVAC) duct system. Such a method is being used as part of a larger investigation on acoustical prediction methods to allow for comparison of measured data to results from attenuation predictions of individual duct elements, such as elbows or dampers. Sound propagation in HVAC duct work is complex. Any measurements of sound energy in the duct must address the characteristics of sound propagation in ducts, end reflections, and air turbulence. Investigations are being conducted to understand the extents to which …
Room Acoustics Computer Modeling: Study Of The Effect Of Source Directivity On Auralizations, Michelle C Vigeant, Lily M. Wang, Jens Holger Rindel
Room Acoustics Computer Modeling: Study Of The Effect Of Source Directivity On Auralizations, Michelle C Vigeant, Lily M. Wang, Jens Holger Rindel
Durham School of Architectural Engineering and Construction: Faculty Publications
Auralizations are very useful in the design of performing arts spaces, where auralization is the process of rendering audible the sound field in a space, in such a way as to simulate the binaural listening experience at a given position in the modeled space. One of the fundamental modeling inputs to create auralizations is the source directivity. Standard methods involve inputting the measured source directivity, calculating the impulse response and convolving it with a single channel anechoic recording. An initial study was conducted using this method and the results showed significant differences in reverberation time and clarity index when using …