Large Scale Finite Element Modeling,Simulation and Visualization for Wind Flows in Urban Area Using Virtual Reality

A large-scale finite element modeling, simulation and visualization for wind flows are presented. The modeling method using GIS/CAD data is employed. The stabilized parallel finite element method based on SUPG/PSPG method is employed for the analysis of wind flows. The present method is applied to the simulation of wind flow and contaminant spread in urban area. The visualization based on virtual reality is employed to evaluate the mesh quality and computational results. The computed results are qualitatively in agreement with the experimental results and actual phenomena. The present method is shown to be a useful tool to simulate the wind flows in urban area.

An alternative visualization pipeline for large-scale data sets by using early visibility test point rendering

The amount of produced data required to be visualized and analyzed has grown year by year,and the traditional approach of using larger computational resources or exploiting task and data parallelism seems to have reached its limit.Therefore,a new paradigm for large-scale data visualization becomes highly desired,and in this paper,we propose a new and optimized visualization pipeline which uses a point rendering-based early visibility testing for reducing the unnecessary rendering in the final stage of the visualization pipeline,and we named this technique“Early Visibility Test Point Rendering”.In a densely populated polygonal mesh scene,where multiple triangles may cover a single pixel,unnecessary and wasteful rendering will occur in the final stage of the traditional visualization pipeline,that is,during the rasterization process.Therefore,we propose an alternative visualization pipeline by introducing the“Early Visibility Test Point Rendering”for selecting only the visible polygonal elements for a given visualization scene.This visibility testing can be executed on the CPU side,and only the visible polygonal elements are needed to be sent to the GPU for an optimized rendering.We could verify the effectiveness of our proposed approach by using synthetic datasets,and also a real-world large-scale simulation result.

Introduction to the special issue on virtual reality and visualization for modeling and simulation

Since last year,we have been experiencing the second boom of Virtual Reality.In the first boom during the 1990’s,applications of Virtual Reality to the research field of modeling and simulation were limited because of the cost and complexity in use of the Virtual Reality equipment.However,in the current boom,the situation is very different.Now,we have sophisticated but cheap and user-friendly Virtual Reality tools and environments such as head-mounted display,personal-size naked-eye stereographic displays,high-quality remote visualization systems,and others.We can also utilize personalized ICT devices such as laptop PCs,tablets,and smart phones.On the other hand,it should also be remarked that the recent cutting-edge technologies can provide us with highly real virtual worlds based on ultra-high-resolution images,ultra-large displays,haptics and auditory devices,etc.Availability of the well-established network environments further increases possible application of Virtual Reality.