This study explored the effect of porosity and installation angle, thickness (dimension) and second layer of permeable obstacles on density current control and trapping in the laboratory. For this purpose, an insoluble suspended polymer and two types of groove and cavity obstacles made from plexiglass sheets were selected. The experiments were conducted with two different concentrations, five d...

An optimization problem for the unilateral contact between a pseudoplate and a rigid obstacle is considered. The variable thickness of the pseudoplate plays the role of a control variable. The cost functional is a regular functional only in the smooth case. The existence of an optimal thickness is verified. The penalized optimal control problem is considered in the general case.

We describe a spatial pattern arising from the nonuniform evaporation of a colloidal film. Immediately after the film deposition, an obstacle is positioned above its free surface, minimizing evaporation at this location. In a first stage, the film dries everywhere but under the obstacle, where a liquid region remains. Subsequently, this liquid region evaporates near its boundaries with the dry ...

In an excitable medium, wave breaks are essential for spiral wave formation. Although wave breaks can result from collisions between a wave and an obstacle, it is only when the resultant wave fragments separate from the obstacle ~wave-front–obstacle separation! that a spiral wave will begin to develop. We explored collisions between a piecewise linear obstacle and an incident wave front while v...

We start with a three-dimensional equilibrium problem involving a linearly elastic solid at small strains subjected to unilateral contact conditions. The reference configuration of the solid is assumed to be a thin shallow shell with a uniform thickness. We focus on the limit when the thickness tends to zero, i.e. when the three-dimensional domain tends to a two-dimensional one. In the generic ...

Our purpose is to investigate the effect of a thin dielectric coating on the scattering of a time-harmonic electromagnetic wave by a perfectly conducting metal. An asymptotic expansion of the solution of a model problem is performed relatively to the thickness of the dielectric shell. A suitable scaling as well as an adapted writing of the the curl operator inside the thin shell make it possibl...

As the gate oxide thickness decreases below 2 nm, the gate leakage current increases dramatically due to direct tunneling current. This large gate leakage current will be an obstacle to reducing gate oxide thickness for the high speed operation of future devices. A MOS transistor with Ta2O5 gate dielectric is fabricated and characterized as a possible replacement for MOS transistors with ultra-...

Continuing the analysis of fracture size effect in Part I, which was focused on the maximum force in vertical penetration of ice, Part II tackles the problem maximum force that can be applied by a moving ice plate on an obstacle presented by a fixed structure. Based on an asymptotic approach, approximate solutions for are obtained for the size effects of ice thickness, effective structure diame...

nanotechnology has been shown to have promising roles in the development of various industries including the agricultural sector. the primary purpose of this study was to investigate the researchers’ attitude and the obstacle hampering the development of nanotechnology in the agricultural sector of iran. the population of this study consisted of researchers in national research centers/institut...