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

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在开发通用单元模拟能力的过程中，关键步骤之一是能够生成带有边界曲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质函数分布引起的空间和时间局部化效果，需要一个将几何定义转换为可计算网格的工具。虚拟单元中的几何体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)自动生成的曲面表示(平滑的非结构化多面体曲面网格)，以及3)几何体的拓扑摘要(具有大小度量和邻接关系的所有连续曲面和体积区域的列表)。拓扑摘要将形成自动执行任何空间模拟的非空间(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.