The finite-difference time-domain (FDTD) method is used to obtain numerical solutions of infinite periodic structures without resorting to the complex frequency-domain analysis, which is required in traditional frequency-domain techniques. The field transformation method is successfully used to model periodic structures with oblique incident waves/scan angles. Maxwell’s equations are transforme...

Modeling blood flow in larger vessels using lattice-Boltzmann methods comes with a challenging set of constraints: a complex geometry with walls and inlets and outlets at arbitrary orientations with respect to the lattice, intermediate Reynolds (Re) number, and unsteady flow. Simple bounce-back is one of the most commonly used, simplest, and most computationally efficient boundary conditions, b...

The effect of (a huge number of) pumping holes on beam dynamics and stability, described in terms of coupling impedances, is a fundamental issue and has been carefully investigated, both theoretically [1] and experimentally [2]. With the exception of a few very simple pipe geometris, for which the modal expansion of the electromagnetic field is available, beam coupling impedances can be only co...

Given a simplicial complex K with weights on its simplices and a chain on it, the Optimal Homologous Chain Problem (OHCP) is to find a chain with minimal weight that is homologous (over Z) to the given chain. The OHCP is NP-complete, but if the boundary matrix of K is totally unimodular (TU), it becomes solvable in polynomial time when modeled as a linear program (LP). We define a condition on ...

A new mathematical model of time fractional order heat equation and fractional order boundary condition have been constructed in the context of the generalized theory of thermo piezoelasticity. The governing equations have been applied to a semi infinite piezoelectric slab. The Laplace transform technique is used to remove the time-dependent terms in the governing differential equations and the...

In this work, for better understanding of drug delivery systems, blood flow over a ceramic nanoparticle is investigated through microvessels. Drug is considered as a nanoparticle coated with the rigid ceramic. Due to the low characteristic size in the microvessel, the fluid flow is not continuum and the no-slip boundary condition cannot be applied. To solve this problem lattice Boltzmann method...

The study of planktonic foraminifera in Jorband section reveals two major events in Campanian- Maastrichtian boundary and early-late Maastrichtian bio-diversification. In this study, occurrence and species richness of planktonic foraminifera in Jorband area show the warm marine environment dominant during early to late Campanian and it could be correlating by tropical and subtropical biozones. ...

For implementation&#10 of the free surface boundary condition, a new subroutine has been introduced to an existing steady 3-D body fitted code. This code was previously written for steady flow simulation in closed ducts. The algorithm used in this subroutine reduces the instability problem according to the free surface wave generation. For code validation, it was applied to two different open c...

Three circular piezoelectric actuators: Bimorph, Thunder, and Radial Field Diaphragm (RFD) function as oscillating diaphragms within a cavity to produce a zero net mass flux air jet. To characterize each diaphragm, displacement response and vibrational characteristics with varying mechanical and electrical boundary conditions were investigated using a saw tooth waveform at 5 Hz. Clamping pressu...

A stochastic approach to a recently proposed model of terminal current fluctuations is presented. Two kinds of boundary conditions suitable for noise simulations in semiconductor devices are proposed. The properties and the domain of application of the two models are investigated and the conclusions are drawn from numerical experiments.