In this paper the influence of non-acoustic properties on the sound absorption coefficient of polyurethane foams as a porous medium is investigated. Biot’s equations with transfer matrix method, as the solution approach are employed to evaluate the sound absorption coefficient of selected polyurethane foams. The major issue is the dependency of non-acoustic properties on each other which makes ...

the course of consecutive experiments in this report aimed to a research or introductory identification about mechanical and acoustical properties of maple (acer velutinum) wood. studied factors were included quality factor (due to internal friction), acoustic coefficient, acoustical conversion efficiency as well as the modulus of elasticity (young’s modulus) which they were all accomplished us...

in this study, the disadvantages of wood, which is widely employed in producing music instruments, are discussed. for example, high moisture sensitivity, low impact resistance, and time-consuming procedure as well as various properties of different species or in several parts of one specimen which are the main problems of wooden music instruments are extensively discussed in this paper. many ma...

Carbon / epoxy composite is one of the most useful polymer matrix composites that has special properties such as high strength-to-weight ratio, high hardness, high corrosion resistance, Resistance to nuclear radiation has high consumption in different industries such as aerospace industry. Therefor monitoring of loading of this type of composite is important. In order to determine failure mecha...

with the aim of identifying failure mechanism in oriented strand boards, failure behavior of wood strands under tensile load was investigated using acoustic emission technique. resinated and unresinated strands were arranged at top, middle and bottom section of the board before pressing. tensile and acoustic emission tests were performed simultaneously on treated and control samples. using tens...

The presented research aims to reduce the uncertainty in selection of noise wall panel materials, and thus improve traffic management process Republic Croatia. An evaluation concrete, metal, wood, transparent panels is performed material procedure planning design walls. Properties made these four basic materials are studied under assumption that acoustic requirements relating structure have bee...