This summer, Dr. Greg Faris and I used new optical techniques to create a system for stimulated Rayleigh-Brillouin scattering measurements that will evolve into a microscopy system for biological applications. The system consists of a pump and a probe beam, which are modulated to different frequencies, amplitudes, and pulse lengths by acousto-optic (AOM) and electro-optic modulators (EOM). The ...

We calculated the Fresnel paraxial propagator in a birefringent plate having topological charge q at its center, named "q-plate." We studied the change of the beam transverse profile when it traverses the plate. An analytical closed form of the beam profile propagating in the q-plate can be found for many important specific input beam profiles. We paid particular attention to the plate having a...

This work presents a numerical analysis of entropy generation in Γ-Shaped enclosure that was submitted to the natural convection process using a simple thermal lattice Boltzmann method (TLBM) with the Boussinesq approximation.  A 2D thermal lattice Boltzmann method with 9 velocities, D2Q9, is used to solve the thermal flow problem. The simulations are performed at a constant Prandtl number (Pr ...

We consider the following constrained Rayleigh quotient optimization problem (CRQopt) $$ \min_{x\in \mathbb{R}^n} x^{T}Ax\,\,\mbox{subject to}\,\, x^{T}x=1\,\mbox{and}\,C^{T}x=b, where $A$ is an $n\times n$ real symmetric matrix and $C$ m$ matrix. Usually, $m\ll n$. The also known as eigenvalue in literature because it becomes if linear constraint $C^{T}x=b$ removed. start by equivalently tra...

In this paper, the dynamic stability analysis of a simply supported beam carrying a sequence of moving masses is investigated. Many applications such as motion of vehicles or trains on bridges, cranes transporting loads along their span, fluid transfer pipe systems and the barrel of different weapons can be represented as a flexible beam carrying moving masses. The periodical traverse of masses...

‎in this paper‎, ‎we have investigated the chaotic behavior of thermal convection in couple stress liquid saturated porous layer subject to gravity‎, ‎heated from below and cooled from above‎, ‎based on theory of dynamical system‎. ‎a low dimensional lorenz‎- ‎like model is obtained by using galerkin-truncation approximation‎. ‎we found that there is proportional relation between scaled couple ...

Multi-spot optics are applied for process parallelizing if the demand on throughput in mass production rises or large areas of material have to be processed. We investigate the usage of microlens arrays as multifunctional elements for forming an arbitrary shaped laser beam into a spot-, a ring-spotor a line-array pattern. It can be shown that the intensity distribution of each spot is equal to ...

We study the boundary controllability problem for a multilayer Rao-Nakra sandwich beam. This beam model consists of a Rayleigh beam coupled with a number of wave equations. We consider all combinations of clamped and hinged boundary conditions with the control applied to either the moment or the rotation angle at an end of the beam. We prove that exact controllability holds provided the damping...