ABSTRACT
Objective To develop a new algorithm to reconstruct the distribution of acoustic sources of magnetoacoustic tomography with magnetic induction(MAT-MI)in the acoustic inhomogeneous media,which is developed on the basis of generalized finite element method (GFEM) and modified time inversion algorithm. Methods The acoustic and acoustic coupling theory and the basic equations of acoustics were used to study the forward and inverse problems of the acoustic inhomogeneous concentric sphere magneticacoustic coupling model. The solution of acoustic non-uniform media wave equation based on GFEM was proposed.The method solved the problem of acoustically inhomogeneous media sound source reconstruction and conductivity reconstruction.At the same time,the distribution of velocity was reconstructed by rotating the pairs of transducers and the time reversal algorithm. Results The proposed algorithm could accurately reconstruct the acoustic source distribution in acoustic inhomogeneous media,and could obtain the distribution of sound velocity during the reconstruction of sound source and recover the image well. Conclusion The proposed algorithm had its feasibility and effectiveness verified,and gains advantages in MAT-MI reconstruction of acoustic inhomogeneous media.
ABSTRACT
Meshless methods are recently developed numerical methods which require only node informa- tion. This paper introduces the basic principles and history of meshless methods, the principles and implementation of the moving least square method taking Galerkin method as an example. Finite points mixed method (FPMM) and its application in solving electrocardiogram(ECG) forward problem is also introduced. Foreground and problems need to be solved concerning the application of meshless methods in the study of ECG forward problem are discussed.