3 D IMAGE RECONSTRUCTION, GEOMETRY FEATURE EXTRACTION, & GRID GENERATION

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。在产生通用单元模拟能力的过程中，关键步骤之一是能够生成具有边界面的离散计算体网格，并在这些离散网格上执行计算。为了表示由显式几何特征或异构函数分布引起的空间和时间局部效应，需要一种将几何定义转换为可计算网格的工具。虚拟单元中的几何图形现在被分解为三个组件；1)基于体积的规范（图像堆栈或一组解析的内外函数），2)自动生成的表面表示（光滑的非结构化多面体表面网格），以及3)几何形状的拓扑摘要（具有尺寸度量和邻接关系的所有相邻表面和体积区域的列表）。拓扑摘要将构成对任何空间模拟自动化非空间（混合良好）近似的基础。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. One of the critical steps in the process of producing a general purpose cell simulation capability is being able to generate discrete computational volume meshes with bounding surfaces and perform computations upon these discrete meshes. For representing spatially and temporally localized effects, which result from explicit geometric features or heterogeneous function distributions, a tool that transforms geometry definitions into computable meshes is required. Geometries within the Virtual Cell are now decomposed into three components; 1) a volume-based specification (an image stack or a set of analytic inside-outside functions), 2) an automatically generated surface representation (smoothed unstructured polyhedral surface mesh), and 3) a topological summary of the geometry (list of all contiguous surfaces and volume regions with size metrics and adjacency relationships). The topological summary will form the basis for automating non-spatial (well mixed) approximations for any spatial simulation.