?a òa
μ?×è?1??2?3é????ê?(Electrical Impedance Tomography￡??ò3?EIT)ê??üD??ê·￠?1?eà′μ?ò???D?D?ò??§3é????ê?￡??üê?í¨1y??éú??ì?±í????DDμ?2aá?à′·′ó3éú??ì??úμ?μ??êμ?±??ˉ?é???￡ó???óDμ?ò??§3é????ê??à±è￡?è?Xé???3é???￠?????ú??2?é¨?è3é??(CT)ò??°o?′?12??(MRI)μè￡?EIT2?????óD1|?@@é??μ?D??ê￡????ò?1òòá????￠?T′′?￠ì??yD??￠·?±?Dˉ′?μèì?μ?￡????°ò?3é?aμ±??éú??ò??§1¤3ìμ???′ó?D????ìa￡?óD×?1?à?μ?ó|ó??°?°?￡
????μ???μ?ê??D??EIT??ê?μ?èí?têμ??1y3ì?￡ê×?è￡?í¨1y???t??EIT??DD?¨?￡￡? êμ???ùóúMatlabμ?óD?T?a?ê·??￠í?μ?Laplace·?3ì±?·??-àíoí?¨á￠EIT?y?êìaμ?óD?T?a3ì￡???′?￡??????êìa?Dμ?í??????¨??·¨??DD?D??￡?í?μ?á?DT?yNewton-Raphsonμü′ú??·¨μ?μü′ú1y3ì￡?2￠?ú′??ù′?é?ìá3?ò????ùóú×ü±?2??y?ò?ˉ??ê?μ?Newton-Raphsonμü′ú??·¨￡??ù′?￡?à?ó?DT?yNewton￡?Raphsonμü′ú??·¨￡??ùóúmatlab??ì¨??DDí??????¨￡?2ìμ￥??oíá???3é????±ê?é????í??????¨D§1?￡?2￠?ò????11í?????DDá?·???ì???￡??D??á?2?í?2?êy??3é???á1?μ?ó°?ì?￡ ?á1?±í?÷￡?ó|ó?????μ?óD?T?a?￡Dí￡?í¨1yDT?yNewton-Raphsonμü′ú??·¨?ü1?μ?μ?±è?????úμ?EIT??11í???￡?2￠?ò?y?ò?ˉ2?êyoíμü′ú2?3¤????3é???á1?óD×?ò??¨μ?ó°?ì?￡×?oó2éó?êμ2aêμ?éêy?Y￡?í¨1yé?ê???·¨￡?μ?μ???11í????￡



1??ü′ê￡oμ?×è?1??2?3é??; ?y?êìa￡?; ???êìa￡?óD?T?a￡??y?ò?ˉ
ABSTRACT
Electrical Impedance Tomography(EIT)is a developing technology for medical imaging these years￡?which is to calculate the changes of conductivityof biomedical issues￡?Comparedto the current iInaging technology,such as X-ray,Computed Tomography,and MagneticResonanceImaging￡?EIT has its ownadvantages￡?e￡?g￡?functional imaging￡?ow-cost,non-invasion and portability￡?And these features make it become a hot point for study and discussion in biomedical engineering area￡?.
Paper based on the study of the principle of EIT, the preliminary study on the hardware system, puts forward an improved EIT system. The article focuses on the research of EIT technology software implementation process. First of all, based on 2d EIT modeling, implementation, Laplace equation is derived based on Matlab finite element subdivision EIT is variational principle and establishment of the finite element process; Second, the study of inverse problem of image reconstruction algorithm, modified Newton -- Raphson iteration algorithm was deduced in the iterative process, and based on this, advances a kind of based on total variation regularization techniques of Newton -- Raphson iterative algorithm; . Again, using the modified Newton Raphson iteration algorithm, the image reconstruction based on matlab platform and examine a single case and two imaging target image reconstruction effect, and the reconstructed image are analyzed and discussed, studied the influence of different parameters on the imaging results. Application results show that the improved finite element model, through the modified Newton Raphson iteration algorithm can get clearer EIT reconstruction image, and the regularization parameter and the iteration step length has a certain influence on the imaging results. Then using the measured experimental data, through the above algorithm, reconstruction image is obtained.



Key words￡oEIT; Forward Problem ; Inverse Problem￡?Finite Element￡?Regularization￡?







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1 D÷ ?? 1
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1.4 ±???μ?×é?ˉ?á11 2
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2.4 EIT?y?êìaμ?óD?T?a?ê·??￡Dí 5
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4.3.2 μü′ú2?3¤ 15
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