Transport Research International Documentation (TRID) https://trid.trb.org/ en-us Copyright © 2024. National Academy of Sciences. All rights reserved. http://blogs.law.harvard.edu/tech/rss tris-trb@nas.edu (Bill McLeod) tris-trb@nas.edu (Bill McLeod) Transport Research International Documentation (TRID) https://trid.trb.org/Images/PageHeader-wTitle.jpg https://trid.trb.org/ Physics-based modelling for aircraft noise and emission predictions https://trid.trb.org/View/2145727 Mon, 03 Apr 2023 16:46:58 GMT https://trid.trb.org/View/2145727 Methods for motor noise evaluation and control in electric vehicles https://trid.trb.org/View/1367698 1 kHz) tonal components, the overall satisfaction and annoyance ratings were improved. The annoyance due to tonal components, stationary as well as speed-dependent, was further studied in Paper 2. The psycho-acoustic metric prominence ratio (PR) was used to quantify the tone levels relative to the adjacent background noise. It was found that for PR-levels below 3 dB, the perceived annoyance was similar independent of frequency range. Increased PR-level provided higher probability of detecting the tones and the perceived annoyance was significantly increased compared to PR<3 dB for tones above 2.5 kHz. The findings from Paper 1 and 2 provide foundation for complete vehicle interior acoustic target specification. The following two papers (Paper 3 and 4) focus on the main mechanical system properties that are responsible for the airborne radiation and transfer of electric powertrain induced noise. Paper 3 has emphasis on the experimental determination of acoustic transfer functions (ATFs) between the car’s interior to multiple positions located on the stator shell surface of an electric rear axle drive. It addresses the ATFs’ spatial resolution with respect to estimated interior noise for theoretically derived and measured surface vibrations. A reciprocal relation was assumed; therefore the measured ATFs could be used to inversely reproduce the sound transmission from the stator shell to the interior. ATFs and surface velocities are also central in Paper 4, where a method for in-situ determination of radiated sound power from a stator shell was presented and validated. By acquiring the operational deflection shape due to an electro-magnetic radial force wave, a simplified expression for the radiation efficiency was estimated. Paper 3 and 4 highlights the advantages of the rotational symmetric force excitation acting on the stator housing which enables sound power as an acoustic source characterization which perhaps is the most adequate measure for system target setting directed towards external suppliers.]]> Tue, 01 Sep 2015 11:22:41 GMT https://trid.trb.org/View/1367698 MOTORCYCLE SAFETY, ENVIRONMENTAL EFFECTS, AND PERFORMANCE STUDIES. 1964-JUNE, 1980 (A BIBLIOGRAPHY WITH ABSTRACTS) https://trid.trb.org/View/155829 Tue, 27 Oct 1981 00:00:00 GMT https://trid.trb.org/View/155829 HIGHWAY NOISE CRITERIA STUDY: TRAFFIC NOISE DATA BASE https://trid.trb.org/View/150897 Thu, 27 Aug 1981 00:00:00 GMT https://trid.trb.org/View/150897 INVESTIGATION OF THE ENVIRONMENTAL POLLUTION AND DAMAGE BY URBAN TRAFFIC - NOISE AND EXHAUST GASES (UNTERSUCHUNG DER UMWELTBELAESTIGUNG UND UMWELTSCHAEDIGUNG DURCH DEN STRASSENVERKEHR IN STADTGEBIETEN - LAERM UND ABGASE) https://trid.trb.org/View/63527 Wed, 16 Feb 1977 00:00:00 GMT https://trid.trb.org/View/63527 FIRST REPORT ON STATUS AND PROGRESS OF NOISE RESEARCH AND CONTROL PROGRAMS IN THE FEDERAL GOVERNMENT. VOLUME 1: REPORT ON STATUS AND PROGRESS https://trid.trb.org/View/29488 Wed, 05 Nov 1975 00:00:00 GMT https://trid.trb.org/View/29488 TRANSPORTATION NOISE AND ITS CONTROL https://trid.trb.org/View/9476 Fri, 27 Sep 1974 00:00:00 GMT https://trid.trb.org/View/9476 TRUCK NOISE III-A. PRELIMINARY NOISE DIAGNOSIS OF FREIGHTLINER DATUM TRUCK-TRACTOR https://trid.trb.org/View/10600 Thu, 31 Jan 1974 00:00:00 GMT https://trid.trb.org/View/10600