Three Algorithms and Three Electrode Models for Electrical Impedance Image Reconstruction

電阻抗斷層掃描是一種技術可以重建量化人體內部組識電性參數之空間分佈，這種電阻係數與介電係數是無法由其他醫學成像系統來得到。本論交將探討改良型牛頓－拉遜法，模擬退火法及基因演算法以發展電阻抗影像重建演算法。從結果顯示，模擬退火法與基因演算法均可以重建電阻係數分佈動態影像，同時爲降低此兩種方法之自由度，也設計一可從測量而得之電壓導引技術。附此之外。改良型代牛頓－拉遜法也改進了影像對比。針對此三種電壓模型加以研究，其中具有最佳效能之間隙模型也包含於有限元素法之正向解法。

關鍵字

電阻抗成像系統；電阻係數；介電系數；影像重建演算法

並列摘要

Electrical impedance tomography is a technique for reconstructing the spatial distribution of the parameters characterizing the electrical properties of tissues within a body. These parameters, conductivity and relative permittivity, cannot be obtained by other imaging modalities. In this paper, the simulated annealing, the genetic algorithms, and the Newton-Raphson method are developed for electrical impedance image reconstruction. From the results, both the simulated annealing and genetic algorithm based methods are demonstrated to be feasible for producing the dynamic image of resistivity distribution. In order to reduce the number of degree of freedom in these two methods, a guided technique based upon the voltage measurements is also designed. In addition, a modified Newton-Raphson method is also proposed for improving the image contrast. Three electrode models for describing the effect of electrode are also investigated. Afterwards, A simple gap electrode model for its best performance is also included in the FEM forward solver.

並列關鍵字

Electrical impedance tomography ； Resistivity ； Permittivity ； Reconstruction algorithm

國際替代計量

Three Algorithms and Three Electrode Models for Electrical Impedance Image Reconstruction

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