The assessment of creep damage in steels employed in the power generation industry is usually carried out by means of replica metallography, but the several shortcomings of this method have prompted a search for alternative or complementary non-destructive techniques, ranging from ultrasonic to electromagnetic methods, hardness measurements and nuclear techniques. A critical review of the main ...

Using a local plane wave assumption, one can determine the normal incidence sound absorption coefficient of a surface by measuring the acoustic pressure and the particle velocity normal to that surface. As the measurement surface lies in front of the material surface, the measured active and incident acoustic power will generally deviate from those at the material surface, leading to a possibly...

A technique is presented in this paper for the analysis of acoustic radiation of baffled planar sources. This method is based on the concept of the radiation matrix which is a representation of the sound field radiated by complex sources. Both sound power and far-field pressure can be estimated using this method. Numerical simulation and experimental investigation were carried out to verify the...

Memory for order is markedly impaired by the presence of irrelevant sound, even though participants are instructed to ignore the sound. Although a great deal of research has disclosed some features of the task and of the sound that augment or reduce the degree of interference, one important issue of the irrelevant sound effect not yet resolved is whether speech has a special status. This study ...

In this paper, we propose a method for reproducing different sound for multiple users by forming a narrow area, where the users can listen only the desired sounds. We have proposed a sound field control method for narrow area by combining Null-space Based Sound Field Control (NBSFC) and liner loudspeaker array. NBSFC filtering can suppress the sound pressure on the each control point and mainta...

Sound velocity and attenuation in liquid sulfur have been measured at temperatures from 80 °C in the super cooled state through the melting temperature ~about 120 °C! to 200 °C under saturated pressure. The measurements were performed with a pulsed phase sensitive technique at frequencies from 5 to 22 MHz. Accuracy of the sound velocity measurements was 0.1%. A distinct feature in sound velocit...

This paper deals with the problem of sound propagation in urban areas, a real tool leading to smart cities design. It begins by studying the propagation of sound in order to determine and extract the physical parameters that direct this propagation. Then it deals with the formalism of cellular automata and their relation to the specification of physical phenomena with discrete events, such as s...

The sound quality inside a car is a very important aspect of automobile design. Many different sources produce sounds that can be heard inside a car. Previous studies have investigated the sound quality of the sources, such as those produced by the engine [1,2], door closing [3,4], and power windows [5,6]. Recent developments in vehicle design have led to a reduction in various sound levels, pr...

[1] Passive ocean acoustic measurements may provide a safe and inexpensive means of accurately quantifying the destructive power of a hurricane. This is demonstrated by correlating the underwater sound intensity of Hurricane Gert with meteorological data acquired by aircraft transects and satellite surveillance. The intensity of low frequency underwater sound measured directly below the hurrica...