We show that 5-minute acoustic oscillations may resonantly convert into Alfvén waves in the β∼1 region of the solar atmosphere. Considering the 5-minute oscillations as pumping standing acoustic waves oscillating along unperturbed vertical magnetic field, we find on solving the ideal MHD equations that amplitudes of Alfvén waves with twice the period and wavelength of acoustic waves exponential...

the thomas-fermi (tf) equation has proved to beuseful for the treatment of many physical phenomena. in this pa-per, the traveling wave solutions of the kdv equation is investi-gated by the simplest equation method. also, the effect of differentparameters on these solitary waves is considered. the numericalresults is conformed the good accuracy of presented method.

Many acoustic instruments create a harmonic series, a collection of sine-waves uniformly spaced in frequency. A listener aggregates such collections of sine-waves, or partials, into a single pitch. Some acoustic instruments allow portamento, the smooth glide from one pitch to another. For example, the violin and trombone. During acoustic portamento, each sine-wave transitions in parallel motion...

An experiment has been performed to study the behavior of dust acoustic waves driven at high frequencies f 100 Hz , extending the range of previous work. In this study, two previously unreported phenomena are observed—interference effects between naturally excited dust acoustic waves and driven dust acoustic waves, and the observation of finite dust temperature effects on the dispersion relatio...

This study introduces optical feedback interferometry as a simple and effective technique for the two-dimensional visualisation of acoustic fields. We present imaging results for several pressure distributions including those for progressive waves, standing waves, as well as the diffraction and interference patterns of the acoustic waves. The proposed solution has the distinct advantage of extr...

The propagation of borehole acoustic waves in the presence of various types of heterogeneous formations is investigated by modeling them as stratified media with varying velocity-depth distributions. Two types of formations are modeled, using translational and cyclic random models, respectively. Borehole acoustic wavefields for the heterogeneity formation models are simulated using finite-diffe...

A review is presented of recent experiments performed on the University of Iowa DC discharge dusty plasma device on various aspects of dust acoustic waves. A brief introduction to the physics of dusty plasmas and the dust acoustic wave is first presented. Three experiments are then described: (i) observation and interpretation of large amplitude (nonlinear) dust acoustic waves; (ii) evolution o...