We present finite difference schemes for solving the variable coefficient Poisson and heat equations on irregular domains with Dirichlet boundary conditions. The computational domain is discretized with non-graded Cartesian grids, i.e., grids for which the difference in size between two adjacent cells is not constrained. Refinement criteria is based on proximity to the irregular interface such ...

A novel hybrid numerical scheme with built-in hyperviscosity has been developed to address the accuracy and numerical instability in numerical simulation of isotropic compressible turbulence in a periodic domain at high turbulent Mach number. The hybrid scheme utilizes a 7th-order WENO (Weighted Essentially Non-Oscillatory) scheme for highly compressive regions (i.e., shocklet regions) and an 8...

We report on recent insights into the interaction between ultra-fast laser pulses and plasmonic nanoparticles . We discuss femtosecond near-field ab lation as a simple but versatile too l for the nanoscale modification of surFaces and the high-resolution measurement of a nanostructure's near fi e ld . Two model systems are presented, illustrating the comp\t:Xily of near-field distributions. Fur...

During air-gap formation in interconnects, decomposition process of the sacrificial layer induces deformation of a low-k dielectric cap layer. For analysis of ensuing structural instability, a logistic kinetics model is introduced to describe the removal process of the sacrificial layer, and finite difference method (FDM) is applied to evaluate the deformation behavior of the cap layer. The ins...

BACKGROUND Elective aesthetic surgeries are increasing in the Iranian population with reasons linked to body image dissatisfaction and psychological symptoms. This study compared the body image dissatisfaction and psychological symptoms among invasive and minimally invasive aesthetic surgery patients and a control group. METHODS Data from 90 participants (invasive aesthetic surgery=30 ...

In this paper we present two unconditionally energy stable finite difference schemes for the Modified Phase Field Crystal (MPFC) equation, a sixth-order nonlinear damped wave equation, of which the purely parabolic Phase Field Crystal (PFC) model can be viewed as a special case. The first is a convex splitting scheme based on an appropriate decomposition of the discrete energy and is first orde...

Snakes have become a standard image analysis technique with several variants now in common use. We have developed a software package called “United Snakes”. It unifies the most important snake variants, including finite difference, B-spline, and Hermite polynomial snakes, within the framework of a general finite element formulation with a choice of shape functions. Furthermore, we have incorpor...

Poisson editing, introduced in 2003, is becoming a technique with major applications in many different domains of image processing and computer graphics. This letter presents an exact and fast Fourier implementation of the Poisson editing equation proposed in (Pérez et al., 2003). The proposed algorithm can handle well all Poisson editing methods that are currently implemented with finite diffe...

BACKGROUND Aesthetic surgery procedures have been performed at dramatically increased rates in recent years in Iran. Few researches exist documenting the usage of body image coping strategies and its relationship in seeking surgery. METHODS The present research examined data from 90 aesthetic surgery participants (30 Subjects each in invasive, minimally-invasive, and control groups). A...

Finite-difference approximations are succinctly represented by their stencils, a set of weights that when applied to adjacent samples of a function approximate some differential operator. In image processing the samples are pixels or voxels, and the differential operators must be inverted for smoothing or painting applications. For efficiency in such applications requiring inverses, the finited...