The paper presents the results of experiments on the technical fabric ''Panama'' carried out with the purpose of identification of inelastic properties of the warp and weft as well as the identification techniques based on the least-squares method. The material parameters are calculated on the basis of the uniaxial tension test in the warp and weft directions. The dense net type of a finite element is proposed to express the behaviour of the technical fabric in the FEM analysis. The Bodner-Partom and Chaboche viscoplastic models are applied to the description of the warp and weft properties. The results are verified by numerical simulation of the laboratory tests.

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The main aim of this study was to estimate the discrepancies of results of equivalent sound level (L AeqT) measured locally, and the SPL changes of acoustic pressure level during measurement. Changes of measured acoustic pressure level in time occur during field measurements independently from the source, which is the object of the study. In the case of some sources-for example air conditioners-the changes are little, at up to 4 dB. Other sources, like for instance road traffic, show higher than 10 dB fluctuations of acoustic pressure level in any observation time (Fig. 1). Cyclical fluctuations of audible noise levels of wind turbines registered at the turbine main tower, especially connected with the frequency of rotor blade passing the turbine main tower,mare called by many researchers a modulation of noise amplitude [1-3]. However, the author of this article uses the term "fluctuation of

Infrasounds are very common in the natural environment. There are various opinions about their harmfulness or lack of harmfulness. One of the reasons of increasing interest in this issue is that there are more and more wind farms appearing close to building estates which are undoubtedly a source of infrasound. It is reasonable to present the results of research of infrasound noise connected not only with wind farms. In this study own results of research of infrasound noise related to daily human activity are presented. The measurements were carried out during housework, travel to the office or shop, and during shopping. The results are shown in the form of values of equivalent levels and 1/3-octave analyses. Taking into consideration the natural sources of infrasound in the environment, the measurements were conducted during both windy and windless weather. On the basis of the results of the measurements it was possible to define the daily exposure to infrasound noise. Those results were also compared with the available in the literature threshold values sensed by people. Estimated level of exposure to noise beyond workplace together with the level of exposure to noise at work enables to define daily exposure level, which means a better assessment of risk of health loss. Increasing social awareness of acoustic threat in everyday life allows us to identify the problem and at the same time improve the quality of rest and efficiency at work.