外文翻译----空气污染的虚拟现实模型(编辑修改稿)

外文翻译----空气污染的虚拟现实模型(编辑修改稿)内容摘要：

onal . The description and parison of these problems has been presented in [4]. It is possible to use the simplest method of the 0th order the nearest neighbour method that interpolates the surroundings of a given station by the same value measured in the station. Voronoi diagrams [1] limit the surrounding borders. Related Delaunay triangulation method presented in Fig. 1 is used for higherorder interpolation (bilinear, cubic, spline). A selected method applied to the array of calculated concentration39。 s values results in the orthogonal de_ning longitude and latitude. The threedimensional model represents a natural presentation of these results. 5 Three Dimensional Model in Matlab and VRML Environment The spline interpolation method has been applied for the data PM10 (particular material up to 10 _m) measured in the AIM system of the Czech Republic at a selected time. The algorithm realized in the Matlab R12 system provides resulting model of air pollution presented in Fig. 2. Figure 2: Result of spline interpolation of PM10 concentration realized in the Matlab system. Virtual Reality Toolbox [2] has been then used for creation of the VRML _le (.wrl). Using any text editor for modi_cation of this _le it is necessary to respect the following requirements for the VRML _le creation: 1. Coordinate systems: Both the Matlab system and the VRML use the righthanded Cartesian coordinate system, but rotated around the xaxis as given in Fig. 3 Figure 3: Coordinate systems in Matlab and VRML 2. Units: While in the Matlab environment it is possible to use any unit system, VRML expects that the length values are given in meters, angles in radians and time in seconds 3. Nodes marking: It is possible to municate with the selected set of the VRML nodes in existing virtual world from Matlab and its Virtual Reality Toolbox provided that the nodes in VRML are named using the DEF keyword. Having in mind these rules it is possible to export a 3D model created in the Matlab environment enabling visualization by mesh or surf mands to VRML environment in a very simple way using vrml(handle。 filename) mand. Object properties de_ned in Matlab and given by the corresponding constant handle are translated into the VRML node parameters in this way. As an example it is possible to assume the point coordinates a。