Vol. 9 No. 14 (1994): Acústica e Vibrações 14

Editorial

SOBRAC is on a path of improvement, after 10 years of its existence. Over the years, we have learned and modified the ways in which SOBRAC was organized, held congresses/symposia, and edited the magazine.

In April 1994, the 15th SOBRAC Meeting was held together with the I Congress Brazil/Argentina, which was one of the biggest technological events in the area of ​​Acoustics and Vibrations in Latin America, with the publication of Annals of 600 pages, 6 ( six) key US speakers and Europe, with sections specialized in the area of ​​individual and collective protection against noise and vibrations, vehicle acoustics, urban noise, active noise control, acoustic materials and devices, with 88 works presented from Brazil, Argentina, Chile, and Mexico.

One of SOBRAC's great achievements in 1994 was the work carried out together with other Latin American Societies such as: the Argentinian Acoustics Association (AdAA), Chilean Acoustic Society (in the reactivation phase), Peruvian Acoustic Society (SPA), and Instituto Mexicano de Acústica (see news on page 71).

The request for copies of the magazine in Brazil and other Latin American countries led to the publication of the magazine in a new form. From this edition onwards, the journal will be in A4 size, with all articles in the same form, with high print quality, that is, the journal is at the same level as other international technical journals. We are composing an editorial group in 1995 in the various areas of acoustics and vibrations to contribute to the quality of the articles.

Consumer demands on acoustic quality in the work and leisure environment significantly increased the demand for technology and information in this area, which stimulated SOBRAC to publish special editions, such as issue no. 13, July/94 on "Noise, Vibrations and Man", this issue on "Vehicle Acoustics", as well as the next issue of July 95, which we intend to address "Industrial Noise".

In this context, the Sociedade Brasileira de Acústica, as a technical entity, dedicates this special edition to Vehicular Acoustics with the support of the Automobile Industry, Universities and Service and Material Providers.

With CONAMA resolutions 06/93 and 07/93 and municipal and state decrees, in addition to the opening of the market for imported vehicles, national technological development in the area of ​​vehicular acoustics becomes inevitable to achieve competitive standards of external noise and internal comfort acoustic.

We would like to thank the contribution of all authors and co-authors of this edition, especially Prof. Helcio Onusic for recommending the topic and for supporting the editing of this volume.

Sarnir N.Y. Gerges, Sobrac President

Summary content:

• Active control of noise in pipelines;
• Identification of vehicular noise sources by measuring sound intensity;
• Transmission via area: internal noise and external noise;
• Exhaust system: fundamentals and projects;
• Tests and acoustic simulation of simple vehicle exhaust;
• Numerical simulation of internal vehicle noise;
• Reduction of the internal noise in intercity buses;
• Internal noise of motor vehicles: the use of loudness;
• Simulation and measurements of engine aspiration noise in the laboratory;
• Experimental study of vibration and noise during clutch pedal actuation; and
• Acoustic characterization of light metal engine test bench using sound intensity; and
• News.