Showing papers on "Noise pollution published in 1987"
TL;DR: In this paper, a method based on the work of Tam and Tanna (1982) for calculating the near field noise spectrum and the spatial distribution of broadband shock associated noise from supersonic jets is proposed.
197 citations
TL;DR: It is suggested that noise does not interfere with short-term memory but that unattended speech does impair performance by disrupting the articulatory loop component of working memory.
Abstract: Studies of ‘noise pollution’ have typically used unpatterned white noise. The present study compares the effect of noise with that of unattended speech. Three experiments required the immediate serial recall of sequences of nine visually presented digits accompanied by silence, noise or unattended speech in an unfamiliar language. Experiments 1 and 2 showed a clear effect of unattended speech at both 75dB(A) and 95dB(A), while unattended noise had no effect in either study. Experiment 3 used a separate groups design combining 95 dB(A) noise and quiet with instructions either to remain silent or to rehearse overtly. Overt rehearsal enhanced recall, while unattended noise again had no effect. It is suggested that noise does not interfere with short-term memory but that unattended speech does impair performance by disrupting the articulatory loop component of working memory. Implications for studies of ‘noise pollution’ are discussed.
163 citations
TL;DR: In this paper, a door and window apparatus includes a pair of longitudinal frames, two transverse frames and two glass sheets respectively disposed among the longitudinal frames defining a vacuum chamber for minimizing sound-wave transmission and preventing noise pollution.
Abstract: A door and window apparatus includes a pair of longitudinal frames, a pair of transverse frames, two glass sheets respectively disposed among the longitudinal and transverse frames defining a vacuum chamber for minimizing sound-wave transmission and preventing noise pollution, and a reinforcing grating intermediately fixed in between the two glass sheets serving as an internal barrier to exclude any intruder through the door or window for security purpose.
25 citations
TL;DR: In this paper, the background levels (L 90 ) from road traffic are high, with half of the study population exposed to levels some 20 dB above those measured in a UK study of the (whole) population of England.
19 citations
05 Oct 1987
TL;DR: In this article, the authors evaluate the potential of interior low-frequency annoyance in homes located near wind turbine installations using a limited program using volunteers to see if they could identify a method suitable for wind turbine noise applications.
Abstract: Given our initial experience with the low-frequency, impulsive noise emissions from the MOD-1 wind turbine and their impact on the surrounding community, the ability to assess the potential of interior low-frequency annoyance in homes located near wind turbine installations may be important. Since there are currently no universally accepted metrics or descriptors for low-frequency community annoyance, we performed a limited program using volunteers to see if we could identify a method suitable for wind turbine noise applications. We electronically simulated three interior environments resulting from low-frequency acoustical loads radiated from both individual turbines and groups of upwind and downwind turbines. The written comments of the volunteers exposed to these interior stimuli were correlated with a number of descriptors which have been proposed for predicting low-frequency annoyance. The results are presented in this paper. We discuss our modifications of the highest correlated predictor to include the internal dynamic pressure effects associated with the response of residential structures to low-frequency acoustic loads. Finally, we outline a proposed procedure for establishing both a low-frequency ''figure of merit'' for a particular wind turbine design and, using actual measurements, estimate the potential for annoyance to nearby communities. 10 refs., 13 figs., 7 tabs.
14 citations
01 Feb 1987
TL;DR: A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise in which certain noise characteristics are independently varied, while the remaining characteristics, such as broadband content, are held constant.
Abstract: A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying, audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure-tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics, such as duration or tonal content, are independently varied, while the remaining characteristics, such as broadband content, are held constant. The system can also generate simulations of the predicted noise characteristics of future aircraft. A description of the synthesis system and a discussion of the algorithms and methods used to generate the simulations are provided. An appendix describing the input data and providing user instructions is also included.
12 citations
TL;DR: In this paper, the effects of maximum noise level and number of noise events on helicopter noise annoyance were found to be consistent with the principles contained in Leq-based noise indices.
Abstract: Reactions to low numbers of helicopter noise events (less than 50 per day) have been studied in a community setting utilizing a new type of study design. Community residents were repeatedly interviewed about daily noise annoyance reactions on days when helicopter noise exposures had, without the residents’s knowledge, been controlled for study design purposes. The effects of maximum noise level and number of noise events on helicopter noise annoyance were found to be consistent with the principles contained in Leq‐based noise indices. Although the best estimate of the effect of number of noise events is very nearly the same as that represented by the energy summation principle contained in Leq‐based indices, the possibility that the number of noise events has only a small effect on annoyance cannot be rejected at the conventional p<0.05 level. The effect of the duration of noise events was also found to be consistent with Leq‐based indices. After removing the effect of differences in duration and noise le...
12 citations
TL;DR: The results of this comparison indicate that CHINA is capable of designing highway noise barriers that are at least equal, in terms of performance, to a human expert.
Abstract: The expert system is a relatively new application of artificial intelligence technology that is beginning to emerge in the field of civil engineering. This new computer‐aided tool has the potential to significantly affect the way today's civil engineer assesses and solves complex problems. An expert system named CHINA (Computerized Highway Noise Analyst) has been developed that is capable of interacting with an existing FORTRAN model that aids an engineer in acoustically designing a highway noise barrier. CHINA executes the design model, interprets the results, and decides if those results are valid. If they are not, CHINA determines new input parameters and re‐executes the design model until a satisfactory design is obtained. Three actual highway noise abatement problems are examined in detail and the design solution from CHINA and a human expert are compared. The results of this comparison indicate that CHINA is capable of designing highway noise barriers that are at least equal, in terms of performance...
9 citations
TL;DR: In this paper, the authors present an overview of appropriate laws, regulations, and prediction models for environmental analysis of transportation systems, focusing on the impact areas of noise analysis, air quality, and water resources, reflecting the engineering related issues of the environmental questions that generally concern civil engineers.
Abstract: Environmental analysis of transportation systems is a comprehensive and demanding task. The environmental planner is required to carefully and objectively examine project data provided by transportation planners and designers, review existing environmental laws and regulations that may affect the project, make appropriate calculations of impact, compare impact values against acceptable criteria, and recommend mitigation where needed. An outline of the procedures followed and the issues addressed during such an analysis are presented in this paper, which is one in a series by members of the Urban Transportation Division's Committee on Transportation Planning. The series of articles is designed to provide guidance on a variety of planning concerns. Discussion in this article is limited to the transportation modes of highways and airports. The impact areas of noise analysis, air quality, and water resources are covered, reflecting the engineering-related issues of the environmental questions that generally concern civil engineers. The paper is not intended to discuss the integrated process for environmental consideration in a manner that would be found in a policy white paper; rather, it presents an overview of appropriate laws, regulations, and prediction models.
9 citations
TL;DR: One of the largest analyses in this country of the need for sound absorptive treatment on highway noise barriers was conducted on the Interstate 440 project in Nashville, Tennessee as discussed by the authors, where special considerations had to be made of potential multiple reflection problems between noise barriers on both sides of the highway, and between vertical rock faces in deep cut sections.
Abstract: One of the largest analyses in this country of the need for sound absorptive treatment on highway noise barriers was conducted on the Interstate 440 project in Nashville, Tennessee. Special considerations had to be made of potential multiple reflection problems between noise barriers on both sides of the highway, and between vertical rock faces in deep-cut sections. This paper presents a detailed discussion of the analysis process and the resultant design of nearly 1/2 mile of sound absorptive barriers. The purpose is to provide information to noise analysts on potential analysis techniques and on problems and pitfalls that may occur. The use of one analysis tool, a computer program developed at Vanderbilt University, will also be described briefly.
5 citations
01 Apr 1987
TL;DR: In this article, a review of available information on the nature of, and potential subjective response to, this environment has been carried out and an interim noise metric is recommended for evaluation of the potential annoyance response of communities to MTR noise environments.
Abstract: : Operations on low level Military Aircraft Training Routes (MTRs) generate a unique noise environments. A review of available information on the nature of, and potential subjective response to, this environment has been carried out. The noise exposure from MTR operations is well below threshold limits for hearing damage or other physiological effects. However, based on this review, an interim noise metric is recommended for evaluation of the potential annoyance response of communities to MTR noise environments. Keywords: Aircraft noise.
TL;DR: In this article, a technique is described that compares the potential noise impacts of construction hauling for a number of project alternatives, based on a modification of the level weighted population method to account for the duration of the hauling activity along various haul routes.
Abstract: Long‐term construction projects have the potential to adversely affect the quality of life of residents living adjacent to the proposed activity. It is therefore desirable to quantify the relative impacts of various options as a part of the overall decision‐making process in choosing a preferred alternative. A technique is described that compares the potential noise impacts of construction hauling for a number of project alternatives. The technique presented herein is based on a modification of the level weighted population method to account for the duration of the hauling activity along various haul routes. The resulting descriptor is termed the level/duration weighted population (LDWP). The use of this technique is demonstrated through application to an actual flood control construction project under study by the U.S. Army Corps of Engineers. The LDWP method allowed the Corps to quantitatively evaluate various project alternatives from the haul noise impact point of view.
01 Jan 1987
TL;DR: In this paper, the authors deal with the effect of noise barriers on the market value of adjacent residential properties, control of airport-and aircraft-related noise in the United States, a traffic-assignment model to reduce noise annoyance in urban networks, a survey of railroad occupational noise sources, a prediction procedure for rail transportation ground-borne noise and vibration, and high-speed rail in California: the dream, the process, and the reality.
Abstract: The six papers in the report deal with the following areas: the effect of noise barriers on the market value of adjacent residential properties; control of airport- and aircraft-related noise in the United States; a traffic-assignment model to reduce noise annoyance in urban networks; a survey of railroad occupational noise sources; a prediction procedure for rail transportation ground-borne noise and vibration; and high-speed rail in California: the dream, the process, and the reality.
31 May 1987
Abstract: Local residential development and the introduction of more restrictive noise regulations in Canada and the United States are creating a need to improve the noise abatement systems at many existing industrial sites including pipeline compressor stations The initial phase of any silencing program should include a study to identify and rank the noise sources Until recently, this type of noise study has been qualitative and inexact, requiring a trial and error approach which addressed only one or two sources at a time and often resulted in a prolonged and costly silencing program The use of sound intensity techniques to determine sound power levels of all noise sources results in lower costs, improved job scheduling and greater likelihood of success of a silencing program This paper discusses a case study which uses sound intensity techniques to rank noise sources at a natural gas compressor plant powered by a gas turbineCopyright © 1987 by ASME
Journal Article•
01 Dec 1987
TL;DR: In this article, the authors analyzed several different elements to identify individual components contributing to rattle, such as windows, doors, wall-mounted objects, bric-a-brac, ductwork, gutters, and light fixtures.
Abstract: Occupants of buildings located in areas of high-level impulse noise usually report that the main annoyance factor is the rattle produced by house components upon vibration. This type of noise is associated with helicopter flybys and blast overpressure from artillery and other military training operations. Methods are needed for mitigating rattles in both existing structures and future construction. This report analyzes several different elements to identify individual components contributing to rattle. Elements studied include windows, doors, wall-mounted objects, bric-a-brac, ductwork, gutters, and light fixtures, among others. In general, the primary source of rattle is any small gap between two hard surfaces that are subject to vibration from an exterior noise source. Upon excitation, these surfaces can impact each other, producing the sound. Other rattle sources are identified, and methods are recommended for eliminating or reducing noise from the individual elements.
01 Dec 1987
TL;DR: In this article, the authors analyzed several different elements to identify individual components contributing to rattle, such as windows, doors wall mounted objects, bric-a-brac, ductwork, gutters, and light fixtures.
Abstract: : Occupants of buildings located in areas of high-level impulse noise usually report that the main annoyance factor is the rattle produced by house components upon vibration. This type of noise is associated with helicopter flybys and blast overpressure from artillery and other military training operations. Methods are needed for mitigating rattles in both existing structures and future construction. This report analyzes several different elements to identify individual components contributing to rattle. Elements studied include windows, doors wall mounted objects, bric-a-brac, ductwork, gutters, and light fixtures, among others. In general, the primary source of rattle is any small gap between two hard surfaces that are subject to vibration from an exterior noise source. Upon excitation, these surfaces can impact each other, producing the sound. Other rattle sources are identified and methods are recommended for eliminating or reducing noise from the individual elements. Keywords: Impulse noise, Buildings, Vibration.
Journal Article•
01 Jan 1987
TL;DR: In this paper, the effects of combined community noise sources on annoyance were investigated, with aircraft noise defined as the major noise source and traffic and air conditioner noise as background noise sources, with a total of 216 subjects were required to make either total or source specific annoyance judgements.
Abstract: Two experiments were conducted to assess the effects of combined community noise sources on annoyance. The first experiment baseline relationships between annoyance and noise level for three community noise sources (jet aircraft flyovers, traffic and air conditioners) presented individually. Forty eight subjects evaluated the annoyance of each noise source presented at four different noise levels. Results indicated the slope of the linear relationship between annoyance and noise level for the traffic noise was significantly different from that of aircraft and of air conditioner noise, which had equal slopes. The second experiment investigated annoyance response to combined noise sources, with aircraft noise defined as the major noise source and traffic and air conditioner noise as background noise sources. Effects on annoyance of noise level differences between aircraft and background noise for three total noise levels and for both background noise sources were determined. A total of 216 subjects were required to make either total or source specific annoyance judgements, or a combination of the two, for a wide range of combined noise conditions.