Download or read book Effectiveness of Predictive Computer Programs in the Design of Noise Barriers Before and After Approach Part II A Final Report written by J. K. Haviland and published by . This book was released on 1981 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effectiveness of Predictive Computer Programs in the Design of Noise Barriers written by J. K. Haviland and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The early work of the Virginia Department of Highways and Transportation on highway traffic noise was focused on a model and a computer program for predicting the noise levels likely to be generated by traffic on proposed highways. The computer program was also used to design barriers to shield neighborhoods from such noise. Because of the cost of noise barriers and the millions of dollars worth of barriers being planned, there was a need to evaluate the efficacy of the predictive computer programs used to design the barriers. For the evaluation, noise measurements were taken before and after construction of an earth berm and plywood wall alongside I-495 in Northern Virginia. The effect of the barrier was taken as the difference between the drop-off in noise level from the roadside to the location under study, as measured before and after construction of the barrier. The measured effect, obtained in this manner, was compared to the effect predicted by hand calculator using the current FHWA model. in a straightforward comparison, all but a few of the measured effects were less than the predicted effects and less than half of them were within 3 dB of the predicted values. However, when the effects of the time of day and human activity within the neighborhood were taken into account, 65% of the noise values obtained during periods of low human activity were within 3 dB of the predicted values. Much of the discrepancy can be attributed to local noise, not accounted for in the prediction, thus it is thought that the computer program can be effectively used in designing noise barriers. By monitoring the neighborhood activity it was determined that while noise such as that from jet lanes and lawn mowers sometimes overrode the traffic noise from I-495, the latter clearly dominated the noise environment of the neighborhood. direct correlations made between variations in L10 levels and truck traffic and between L50 and L90 levels and automobile traffic seem to support the generalization that the L10 levels are controlled by trucks and the L90 levels are controlled by automobiles.

Download or read book Effectiveness of Predictive Computer Programs in the Design of Noise Barriers written by J. K. Haviland and published by . This book was released on 1978 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: A digital data acquisition system has been designed to meet the need for a long duration noise analysis capability. By sampling the DC outputs from sound level meters, it has been possible to make twenty-four hour or longer recordings, in contrast to the one-hour recordings possible on seven-inch analog tape reels. The system is made up of a digital tape recorder, an analog-to-digital converter, an outdoor microphone unit, a weatherproofed microphone, two B & K sound level meters, and other miscellaneous equipment. It has the capability of recording and analyzing data from up to eight channels in linear or decibel format. The operation of the system in terms of its setup, calibration, and the recording of digitized signals, as well as the computer programs used to analyze the signals, are described in this report. Listings of computer programs and of a sample problem are supplied in the appendixes.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book SRIM Index written by and published by . This book was released on 1982 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1983 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by and published by . This book was released on 1983 with total page 1028 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book HRIS Abstracts written by and published by . This book was released on 1988 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Annotated Bibliography of Virginia Transportation Research Council Writings July 1966 June 1989 written by Harry T. Craft and published by . This book was released on 1991 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1982 with total page 1300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.

Download or read book Federally Coordinated Program of Highway Research and Development written by United States. Federal Highway Administration and published by . This book was released on with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Library Acquisitions written by United States. Department of Transportation and published by . This book was released on with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Check list of Virginia State Publications written by and published by . This book was released on 1971 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development and Description of a Computer Program for Predicting Impulse Noise Reduction by Barriers written by Richard Raspet and published by . This book was released on 1987 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Barriers have been proposed as a method of reducing impulse noise from blasts, artillery, and gunfire produced during Army training activities. To estimate the amount of noise reduction they provide, the U.S. Army Construction Engineering Research Laboratory has developed a computer program based on a pulse diffraction prediction method. This report documents the development of the program, outlines barrier design considerations, and describes how to use the program.

Download or read book Government Reports Annual Index Keyword A L written by and published by . This book was released on 1979 with total page 1324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1990 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Federal Register written by and published by . This book was released on 2012-04 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: