摘要
假设肺组织和肿瘤为均匀弹性材料,给出了其本构方程,提出了用位移量来反演肺组织及肿瘤的弹性模量及泊松比的目标函数及其最小值问题,以及相应的梯度逼近法,其中梯度通过基于有限元分析结果的差分作近似计算。通过一实例的CT映像,重建肺部组织及肿瘤在呼吸过程中的三维模型,提取某时刻的肺部边界位移及样点的位移,在此基础上反演了其材料参数,分析了反演方法的收敛情况。
Under the assumption of homogenous elasticity, the constitutive equations of lung tissue and tumor were given. To predict the material parameters, an objective function for inverse analysis was proposed, and an inverse analysis scheme of step-by-step gradient approximation was formulated. The gradients of objective function were approximated by the relevant differences based on the results of finite element analysis. An example was presented to demonstrate the validity of present method. From CT images, the 3D model of lung tissue and tumor were re-constructed, and also the displacements of boundary points and those of internal sample points were separated. Reasonable results of the material parameters were obtained by inverse analysis.
出处
《力学季刊》
CSCD
北大核心
2006年第3期463-468,共6页
Chinese Quarterly of Mechanics
关键词
肺组织
肺肿瘤
有限元法
参数反演
lung tissue
lung tumor
finite element method
inverse analysis
