The behavior of linear and nonlinear dust acoustic waves (DAWs) in an unmagnetized plasma including inertialess electrons and positrons, ions, and mobile positive/negative dust grains are studied. Reductive perturbation method is employed for small and finite amplitude DAWs. To investigate the solitary waves, the Korteweg–de Vries (KdV) equation is derived and the solution is presented. B...

Structure formation and wave phenomena in moderately coupled dusty plasmas." PhD (Doctor of Philosophy) thesis, ABSTRACT Dusty plasmas, defined as plasmas of ions, electrons, neutrals, and charged micron to sub-micron dust particles, support a rich diversity of physical states. These states (ranging from solids to liquids to gas) are determined by the ratio of the Coulomb potential energy betwe...

In this paper we have studied the effect of magneto-static field onpropagation of thermal wave generated in metal by pulsed laser. In fact this interactiongenerate acoustic wave in different mechanisms. However, always the commonmechanism in the interactions of laser pulse and metal is the thermo-elastic wavegeneration. Applying the suitable magneto-static field on the s...

A one-dimensional impact problem is employed for a layered system that comprises heterogeneous materials with different geometrical configurations. The system mimics transmitter for Multiple Integrated Laser Engagement Systems (MILES). The analytical model tracks the stress wave propagation through this layered structure as a result of the mechanical shock from blank rounds as they fired. The r...

Differential pulse-width-pair BOTDA technique is combined with bi-directional Raman amplification and Simplex coding to achieve sub-meter spatial resolution over very long sensing distances. Numerical simulations are used to optimize the power levels of the Raman pumps, avoiding nonlinear effects and pump depletion. Distortions in the Brillouin gain spectrum due to acoustic-wave pre-excitation ...

Sub-meter distributed optical fiber sensing based on Brillouin optical time-domain analysis with differential pulse-width pairs (DPP-BOTDA) is combined with the use of optical pre-amplification and pulse coding. In order to provide significant measurement SNR enhancement and to avoid distortions in the Brillouin gain spectrum due to acoustic-wave pre-excitation, the pulse width and duty cycle o...