Other Engineering Commons^™

How Tonality And Loudness Of Noise Relate To Annoyance And Task Performance” Noise Control Eng. J. 65(2), 71-82., Joonhee Lee, Jennifer M. Francis, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Audible tones in noise generated by building mechanical equipment can be a leading cause of complaints from occupants. A number of metrics have been developed to quantify prominence of a tone, but previous work has shown that the impact of a certain tonality appears to vary with the level of the broadband noise signal. More work on how tonal signals of varying tonality, tone frequency and broadband noise levels relate to annoyance and task performance is needed. This paper investigates such relationships between current noise metrics, annoyance and task performance under assorted tonal noise conditions through subjective testing. Participants rated …

Investigation Of Subjective Perception & Objective Metrics Of Acoustic Room Diffusion, Jay Michael Bliefnick

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

While a variety of assessment methodologies have been proposed to quantify acoustic diffusivity within rooms, a link between these and the perception of diffusion has not been fully established. This study investigated various ways of analyzing diffusion, through both human perception and objective metrics. Numerous impulse response measurements were collected from a physical acoustics testing facility designed for diffusion research. This space featured reversible absorptive/diffusive/reflective wall panels, which allowed numerous testing configurations. One such setup investigated how changing the diffusivity of an isolated wall surface impacted diffusive room conditions. Alternatively, the effects diffuser configurations had on diffusive room conditions were …

Effects Of Time Varying Background Noise Conditions On Human Perception And Performance, Andrew H. Hathaway

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

This thesis was designed to study the effects of changing noise conditions on human perception and performance. In two phases, participants were exposed to a number of noise conditions and their performance on an arithmetic task involving short-term memory was monitored and their subjective perception of noise conditions was collected via questionnaires.

In the first phase, participants were tested while being subjected to RC-29(H) and RC-47(RV) conditions created by broadband noise fluctuating on different time intervals, resembling the changing noise conditions potentially found in modern HVAC systems. These intervals varied from two minutes to ten minutes. Results show a significant …