摘要
在干涉层析中,目前最大的难点仍是对非完全投影数据场的重建,非完全投影数据指观察角小于180°,或者折射车场中存在不透明的遮挡模型,问题的核心在于如何设计结合先验知识的可行算法。对于三维折射率场的重建,先验知识,如折射率非负、遮挡物的尺寸、几何形状、空间位置等是常用的信息。该文提出了一种有效易行的结合先验知识的三维折射率场重建算法,在算法中引进属性矩阵的概念,无需对缺少的投影数据补齐。将该算法应用于高超音速激波风洞中含有遮挡物的三维折射率场的重建,再现了其三维密度分布。
In the field of interferometric tomography, the major problem is to reconstruct three dimensional refractive index field with limited projection data, limited observed angle and objects in the measured field. The core of the question is to design practical algorithm combining with priori information. The priori information may be nonnegative of refractive index, the size and position of opaque object. In this paper a practical algorithm combining projection data with priori in formation is presented, attributed matrix is introduced in the algorithm and the projection data do not need to be interpolated. This algorithm is used to reconstruct three-dimensional refractive field with opaque model, which is sampled in hypersonic wind tunnel.Then its three-dimensional density distribution is reconstructed.
出处
《南京理工大学学报》
EI
CAS
CSCD
1997年第3期273-276,共4页
Journal of Nanjing University of Science and Technology
基金
国家自然科学基金