Controlling the self-assembly of surface-adsorbed molecules into nanostructures requires understanding physical mechanisms that act across multiple length and time scales. By combining scanning tunneling microscopy with hierarchical ab initio and statistical mechanical modeling of 1,4-substituted benzenediamine (BDA) molecules adsorbed on a gold (111) surface, we demonstrate that apparently sim...

A method of ray tracing for free-form optical surfaces has been developed. The ray tracing through such surfaces is based on Delaunay triangulation of the discrete data of the surface and is related to finite-element modeling. Some numerical examples of applications to analytical, noisy, and experimental free-form surfaces (in particular, a corneal topography map) are presented. Ray-tracing res...

We present a generalized method for free-form deformations that combines the traditional freeform deformation model with techniques of scattered data interpolation based on Delaunay and Dirichlet/Voronoi diagrams. This technique offers many advantages over traditional FFDs, including simple control of local deformations. It also keeps all the capabilities of FFD extensions, such as extended fre...

analysis of non-laminar flows in coarse alluvial beds has a wide range of applications in various civil engineering, oil and gas, and geology problems. darcy equation is not valid to analyze transient and turbulent flows, so non-linear equations should be applied. non-linear equations are classified into power and binomial equations. binomial equation is more accurate in a wide range of velocit...

Surface fairing, generating free-form surfaces satisfying aesthetic requirements, is important for many computer graphics and geometric modeling applications. A common approach for fair surface design consists of minimization of fairness measures penalizing large curvature values and curvature oscillations. The paper develops a numerical approach for fair surface modeling via curvature-driven e...

using surface analysis, simultaneous effects of temperature (260-380ºc) and ethanol concentration (0-1%) on dimethyl ether (dme) selectivity, yields of hydrocarbon and dme, and methanol conversion were investigated in methanol dehydration reaction over γ-al2o3 catalyst. methanol conversion and yield of hydrocarbon/dme were found to be significantly affected by temperature and the temperature-et...

Physics-based modeling techniques have been shown to be advanced methods for creating high quality surfaces for application in CAGD. In this paper we propose a physics-based Temporal Computational Object (TCO) as a modeling process that simulates a liquid membrane to generate organic freeform models. This process compliments existing solid and elastic physics based modeling processes by simulat...

The paper studies a method for numerical simulation of free surface flows of viscous incompressible fluids. The approach is based on the level set method for capturing free surface evolution and features compact finite difference approximations of fluid and level set equations on locally refined and dynamically adapted octree cartesian grids. We consider in detail an extension of staggered grid...

Topography complicates the modeling and retrieval of land surface albedo due to shadow effects and the redistribution of incident radiation. Neglecting topographic effects may lead to a significant bias when estimating land surface albedo over a single slope. However, for rugged terrain, a comprehensive and systematic investigation of topographic effects on land surface albedo is currently ongo...