Bieberle M, Hampel U
AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering, Technische Universität Dresden, Dresden 01062, Germany Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, Dresden 01328, Germany
AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering, Technische Universität Dresden, Dresden 01062, Germany Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, Dresden 01328, Germany.
Philos Trans A Math Phys Eng Sci. 2015 Jun 13;373(2043). doi: 10.1098/rsta.2014.0395.
Tomographic image reconstruction is based on recovering an object distribution from its projections, which have been acquired from all angular views around the object. If the angular range is limited to less than 180° of parallel projections, typical reconstruction artefacts arise when using standard algorithms. To compensate for this, specialized algorithms using a priori information about the object need to be applied. The application behind this work is ultrafast limited-angle X-ray computed tomography of two-phase flows. Here, only a binary distribution of the two phases needs to be reconstructed, which reduces the complexity of the inverse problem. To solve it, a new reconstruction algorithm (LSR) based on the level-set method is proposed. It includes one force function term accounting for matching the projection data and one incorporating a curvature-dependent smoothing of the phase boundary. The algorithm has been validated using simulated as well as measured projections of known structures, and its performance has been compared to the algebraic reconstruction technique and a binary derivative of it. The validation as well as the application of the level-set reconstruction on a dynamic two-phase flow demonstrated its applicability and its advantages over other reconstruction algorithms.
断层图像重建基于从物体的投影中恢复物体分布，这些投影是从围绕物体的所有角度视图获取的。如果角度范围限制在小于180°的平行投影，使用标准算法时会出现典型的重建伪影。为了弥补这一点，需要应用使用关于物体的先验信息的专门算法。这项工作背后的应用是两相流的超快有限角度X射线计算机断层扫描。在这里，只需要重建两相的二元分布，这降低了反问题的复杂性。为了解决这个问题，提出了一种基于水平集方法的新重建算法（LSR）。它包括一个用于匹配投影数据的力函数项和一个包含相边界曲率相关平滑的项。该算法已使用已知结构的模拟投影和测量投影进行了验证，并将其性能与代数重建技术及其二元导数进行了比较。水平集重建在动态两相流上的验证和应用证明了其适用性以及相对于其他重建算法的优势。
