Federico Miyara

Spectral information in noise‐mapping: An exploratory study

International standards such as ISO 1996 and ISO 717 as well as noise regulations in several countries are increasingly relying on spectral information in order to assess the acoustical behavior of materials and structures and the effects of noise on people. Nevertheless, the new European Union Directive on the assessment and management of environmental noise reinforces the A‐weighted equivalent level (with appropriate night and evening corrections) as the preferred indicator for noise mapping. Considering that noise maps are a powerful zoning and planning resource, the idea of reporting the mean spectrum of noise at each selected location at different times is proposed and thoroughly justified. Arguments in favor of its feasibility are given, showing that, in spite of the widespread opinion, costs and required time may be reduced considerably by the use of low‐priced, new‐technology auxiliary equipment. Then an exploratory study is reported, in which (a) the spectrum of traffic noise in Rosario (Argentin...

Analysis of lightweight acoustic reflectors

Halls for music performance frequently require the design of acoustic reflectors to redirect the sound waves toward the audience. In order to get adequate reflecting properties the usual criterion is that the surface density be no less than 20 kg/m2. However, this may prove too heavy in certain cases, so other possible solutions must be studied. In this paper, light-weight reflectors, such as medium density fibreboard or plywood panels clamped at their boundaries, where structural rigidity replaces mass at the low frequency end, have been investigated. A compliance model is compared with the mass model showing that the structure is suitable.

Method for generating realistic sound stimuli with given characteristics by controlled combination of audio recordings

Audio recordings are often used to improve ecological validity of stimuli for laboratory research on effects of noise. In this paper a method is proposed for composing realistic environmental sound stimuli with (1) specified overall spectrum and (2) specified statistical distribution of sound event durations and semantic categories. The combination is addressed as a mixed integer linear programming problem. Objective measurements, for eight stimuli and a moderate-size database, validate the method. The mean error in octave bands exposure level is 2.6 dB and the statistical distribution of sound event durations and semantic categories is perfectly matched.

Education in acoustics in Argentina

Over the last decades, education in acoustics (EA) in Argentina has experienced ups and downs due to economic and political issues interfering with long term projects. Unlike other countries, like Chile, where EA has reached maturity in spite of the acoustical industry having shown little development, Argentina has several well‐established manufacturers of acoustic materials and equipment but no specific career with a major in acoustics. At the university level, acoustics is taught as a complementary—often elective—course for careers such as architecture, communication engineering, or music. In spite of this there are several research centers with programs covering environmental and community noise, effects of noise on man, acoustic signal processing, musical acoustics and acoustic emission, and several national and international meetings are held each year in which results are communicated and discussed. Several books on a variety of topics such as sound system, architectural acoustics, and noise control...