168 research outputs found
Aircraft and background noise annoyance effects
To investigate annoyance of multiple noise sources, two experiments were conducted. The first experiment, which used 48 subjects, was designed to establish annoyance-noise level functions for three community noise sources presented individually: jet aircraft flyovers, air conditioner, and traffic. The second experiment, which used 216 subjects, investigated the effects of background noise on aircraft annoyance as a function of noise level and spectrum shape; and the differences between overall, aircraft, and background noise annoyance. In both experiments, rated annoyance was the dependent measure. Results indicate that the slope of the linear relationship between annoyance and noise level for traffic is significantly different from that of flyover and air conditioner noise and that further research was justified to determine the influence of the two background noises on overall, aircraft, and background noise annoyance (e.g., experiment two). In experiment two, total noise exposure, signal-to-noise ratio, and background source type were found to have effects on all three types of annoyance. Thus, both signal-to-noise ratio, and the background source must be considered when trying to determine community response to combined noise sources
Modes of Listening and their Implications to Audience Experience of Orchestral Concerts, with a Case Study of the Toronto Symphony Orchestra
Although listeners adopt similar behaviours according to sociocultural norms in the concert hall, they do not all experience an orchestral performance in the same way. Stockfelts theory of Adequate Modes of Listening provides the framework necessary to examine contemporary listening practices in the modern orchestral context, and provides an alternative to the dominant marketing paradigm. Using a representative case study of the Toronto Symphony Orchestra, the current research performs interviews, document survey and analysis, and concert observation to answer questions such as; do facilitators, orchestra, and audience members agree on a single (or related group) of genre-normative modes of listening? What happens when there is a breakdown in the assumed sociocultural conventions? How can the orchestra facilitate its listeners? By examining the way in which a listener experiences orchestral music, we can strengthen our understanding of contemporary listening practices and develop nuanced approaches to promoting sustainable audiences
PTA en route noise measurements
A long-range advanced turboprop en route noise database was obtained with weather, tracking, and onboard measurements. In-flight noise directivity measurements were made. Data repeatability within a test day was excellent. Day-to-day variability existed and is not completely understood and therefore not predicted. Comparison of a two-dimensional ray-tracing propagation model with the ensemble average ground-measured data was good; however, as stated above, the day-to-day data variability was not completely predicted. Future research will include looking at alternative propagation models. Three-dimensional ray tracing, fast field program, and the parabolic equation are possibilities. The effect of turbulence needs to be accessed
Ground effects on aircraft noise
A flight experiment was conducted to investigate air-to-ground propagation of sound near grazing incidence. A turbojet-powered aircraft was flown at low altitudes over the ends of two microphone arrays. An eight-microphone array was positioned along a 1850 m concrete runway. The second array consisted of 12 microphones positioned parallel to the runway over grass. Twenty-eight flights were flown at altitudes ranging from 10 m to 160 m. The acoustic data recorded in the field reduced to one-third-octave band spectra and time correlated with the flight and weather information. A small portion of the data was further reduced to values of ground attenuation as a function of frequency and incidence angle by two different methods. In both methods, the acoustic signals compared originated from identical sources. Attenuation results obtained by using the two methods were in general agreement. The measured ground attenuation was largest in the frequency range of 200 to 400 Hz. A strong dependence was found between ground attenuation and incidence angle with little attenuation measured for angles of incidence greater than 10 to 15 degrees
Advanced subsonic transport approach noise: The relative contribution of airframe noise
With current engine technology, airframe noise is a contributing source for large commercial aircraft on approach, but not the major contributor. With the promise of much quieter jet engines with the planned new generation of high-by-pass turbofan engines, airframe noise has become a topic of interest in the advanced subsonic transport research program. The objective of this paper is to assess the contribution of airframe noise relative to the other aircraft noise sources on approach. The assessment will be made for a current technology large commercial transport aircraft and for an envisioned advanced technology aircraft. NASA's Aircraft Noise Prediction Program (ANOPP) will be used to make total aircraft noise predictions for these two aircraft types. Predicted noise levels and areas of noise contours will be used to determine the relative importance of the contributing approach noise sources. The actual set-up decks used to make the ANOPP runs for the two aircraft types are included in appendixes
Long-range vertical propagation
Development of the advanced turboprop has led to concerns about en route noise. Advanced turboprops generate low-frequency, periodic noise signatures at relatively high levels. As demonstrated in a flight test of NASA Lewis Research Center's Propfan Test Assessment (PTA) airplane in Alabama in October 1987, the noise of an advanced turboprop operating at cruise altitudes can be audible on the ground. The assessment of the en route noise issue is difficult due to the variability in received noise levels caused by atmospheric propagation and the uncertainty in predicting community response to the relatively low-level en route noise, as compared to noise associated with airport operations. The En Route Noise Test was designed to address the atmospheric propagation of advanced turboprop noise from cruise altitudes and consisted of measuring the noise of an advance turboprop at cruise in close proximity to the turboprop and on the ground. Measured and predicted ground noise levels are presented
Patch or Rebuild: A Comparative Analysis of Multi-Agency Regime vs. Single-Agency Regime within US Domestic Space Traffic Management Regulation
It has been suggested that expansion and modification of the current US regulatory regime is sufficient to regulate space traffic. It has also been suggested that a consolidation of the existing fragmented structure into a single agency would be superior. This article provides a detailed pro vs. con comparative analysis of the two approaches as they relate to civil space traffic and commerce. Expanding commercial needs place specific demands on the regulatory next steps and require thoughtful prioritization and coordination of efforts to ensure a successful future regulatory regime that addresses the competing needs of agencies and industry. The proper fit of domestic regulation within the international landscape, both presently and in the future, is another factor for ultimate success. This paper concludes with recommendations for near-term and longer-term next steps based upon the analytic outcome
Aaron Kohn Attacks Corruption in New Orleans: An Intersection of Media and Politics, 1953-1955
Aaron Kohn’s career as a driven professional crime fighter with the Special Citizens Investigative Committee, and later the Metropolitan Crime Commission, began after the Kefauver Hearings on organized crime, one of the first Senate investigative committee hearings broadcast on the evolving medium of television, gripped the American public in 1950. Sen. Estes Kefauver’s committee visited cities across America, including New Orleans. The hearings’ popularity revealed public thirst for coverage of sensational topics like organized crime, and established how Kohn would soon approach the SCIC job: with force and bombast, featuring flair and sometimes bended truth. Aaron Kohn combined Kefauver’s crusading spirit and media savvy and attempted to apply it to his own long career as a citizen crime fighter in New Orleans, but he met limited success taking on a corrupt establishment in a career that could ultimately be deemed a failure
Aaron Kohn Attacks Corruption in New Orleans: An Intersection of Media and Politics, 1953-1955
Aaron Kohn’s career as a driven professional crime fighter with the Special Citizens Investigative Committee, and later the Metropolitan Crime Commission, began after the Kefauver Hearings on organized crime, one of the first Senate investigative committee hearings broadcast on the evolving medium of television, gripped the American public in 1950. Sen. Estes Kefauver’s committee visited cities across America, including New Orleans. The hearings’ popularity revealed public thirst for coverage of sensational topics like organized crime, and established how Kohn would soon approach the SCIC job: with force and bombast, featuring flair and sometimes bended truth. Aaron Kohn combined Kefauver’s crusading spirit and media savvy and attempted to apply it to his own long career as a citizen crime fighter in New Orleans, but he met limited success taking on a corrupt establishment in a career that could ultimately be deemed a failure
The Aborigines of Central Australia : with vocabularies of the dialects spoken by the natives of Lake Amadeus and of the western territory of Central Australia
Original held in Special Collections, Rare Books, 572.994 W74.Police Officer W.H. Willshire describes his experiences in charge of native police. He was based in what is now Alice Springs, (N.T.) and was able to collect some of the local language and customs of that area and also of the Lake Amadeus area in the S.W. of N.T
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