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Conductivity Image Reconstruction Using Modified Gauss-Newton Method in Electrical Impedance Tomography

전기 임피던스 단층촬영 기법에서 수정된 가우스-뉴턴 방법을 이용한 도전율 영상 복원

  • Kim, Bong Seok (BK21+ Clean Energy Convergence and Integration Center for Human Resources Training and Education, Jeju National University) ;
  • Park, Hyung Jun (Dept. of Materials & Energy Engineering College of IT & Energy, KyungWoon University) ;
  • Kim, Kyung Youn (Dept. of Electronic Engineering, Jeju National University)
  • Received : 2015.04.30
  • Accepted : 2015.06.01
  • Published : 2015.06.30

Abstract

Electrical impedance tomography is an imaging technique to reconstruct the internal conductivity distribution based on applied currents and measured voltages in a domain of interest. In this paper, a modified Gauss-Newton method is proposed for conductivity image reconstruction. In the proposed method, the dimension of the inverse term is reduced by replacing the number of elements with the number of measurement data in the conductivity updating equation of the conventional Gauss-Newton method. Therefore, the computation time is greatly reduced as compared to the conventional Gauss-Newton method. Moreover, the regularization parameter is selected by computing the minimum-maximum from the diagonal components of the Jacobian matrix at every iteration. The numerical experiments with several scenarios were carried out to evaluate the reconstruction performance of the proposed method.

전기 임피던스 단층촬영 기법은 전극들을 통해 전류를 주입하고 이에 유기되는 전압을 측정한 후, 이들 데이터를 기반으로 내부의 도전율 분포를 영상으로 복원하는 방법이다. 이 논문에서는 기존의 Gauss-Newton 방법의 역행렬 항목의 차원을 도메인의 원소의 개수가 아닌 데이터의 개수의 차원으로 바꿔줌으로써, 관심 도메인 내부의 도전율 분포를 보다 빠르게 추정할 수 있는 방법을 제안하였다. 그리고 자코비안 행렬의 대각성분의 최소-최대를 이용하여 조정인자를 계산하는 방법을 함께 제안하였다. 몇 가지 시나리오를 설정하고 모의실험을 통해 제안한 방법의 복원 성능을 비교분석하였다.

Keywords

References

  1. F. A. Holand, R. Bragg, Fluid Flow for Chemical Engineers, Edward Arnold Publisher, 1995
  2. O. C. Jones, J. T. Lin, L. Ovacik, H. Shu, "Impedance imaging relative to gas-liquid systems," Nuclear Engineering and Design, Vol.141, pp.159-176, 1993 https://doi.org/10.1016/0029-5493(93)90100-N
  3. D. L. George, J. R. Torczynski, K. A. Shollenberger, T. J. O'Hern, S. L. Cecciob, "Validation of electrical-impedance tomography for measurements of material distribution in two-phase flows," International Journal of Multiphase Flow, Vol.26, pp.549-581, 2000 https://doi.org/10.1016/S0301-9322(99)00029-4
  4. J. G. Webster, Electrical Impedance Tomography, IOP Publishing Ltd, 1990
  5. D. S. Holder, Electrical Impedance Tomography: Methods, Histrory and Applications, IOP Publishing Ltd, 2005
  6. M. Vauhkonen, Electrical impedance tomography and prior information, Ph.D. Thesis, University of Kuopio, Finland, 1997
  7. T. J. Yorkey, J. G. Webster, W. J. Tompkins, "Comparing reconstruction algorithms for electrical impedance tomography," IEEE Transactions on Biomedical Engineering, Vol.34, pp.843-852, 1987
  8. B. Zhao, H. Wang, X. Chen, X. Shi, W. Yang, "Linearized solution to electrical impedance tomography based on the Schur conjugate gradient method," Measurement Science and Technology, Vol.18, pp.3373-3383, 2007 https://doi.org/10.1088/0957-0233/18/11/017
  9. A. Adler, T. Dai, W. R. B. Lionheart, "Temporal image reconstruction in electrical impedance tomography," Physiological Measurement, Vol.28, pp.S1-S11, 2007 https://doi.org/10.1088/0967-3334/28/7/S01
  10. S. I. Kang, K. Y. Kim, "Image reconstruction using iterative regularization scheme based on residual error in electrical impedance tomography," j.inst.Korean.electr.electron.eng., Vol.18, No.2, pp.272-281, 2014
  11. M. H. Jeon, K. Y. Kim, "Application of matrix adaptive regularization method for human thorax image reconstruction," j.inst.Korean.electr.electron. eng., Vol.19, No. 1, pp.33-40, 2015
  12. W. Q. Yang, L. Peng, "Image reconstruction algorithm for electrical capacitance tomography," Measurement Science and Technology, Vol.14, pp.1-13, 2003 https://doi.org/10.1088/0957-0233/14/1/301