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전기 임피던스 단층촬영법에서 적응 문턱치 기반의 관심영역 기법을 사용한 영상 복원의 개선

Enhancement of Image Reconstruction Using Region of Interest Method Based on Adaptive Threshold Value in Electrical Impedance Tomography

  • 김창일 (한국승강기대학교 승강기공학부) ;
  • 김봉석 (한국승강기대학교 승강기공학부) ;
  • 김경연 (제주대학교 전자공학과)
  • Kim, Chang Il (Faculty of Lift Engineering, Korea Lift College) ;
  • Kim, Bong Seok (Faculty of Lift Engineering, Korea Lift College) ;
  • Kim, Kyung Youn (Department of Electronic Engineering, Jeju National University)
  • 투고 : 2017.03.16
  • 심사 : 2017.07.25
  • 발행 : 2017.08.25

초록

전기 임피던스 단층촬영법은 주입 전류와 측정 전압을 기반으로 관심 도메인 내부의 도전율/저항률 분포를 복원하는 비파괴 영상 복원 기법이다. 본 논문에서는 역문제 계산시간을 줄이고 더불어 공간 해상도도 향상시키기 위해, 적응 문턱치 기반의 ROI(region of interest) 방법을 제안하였다. INTERMODES 방법에 의해 적응 문턱치가 계산이 되고 이 값을 기반으로 전체 도메인으로부터 ROI가 결정된다. 그리고 영상 복원의 계산 도메인을 ROI 내로 국한시켜 반복적 가우스-뉴턴 방법을 적용하여 저항률 분포를 추정하였다. 제안한 방법의 성능을 평가하기 위해 수치실험을 수행하고 그 결과를 비교분석하였다.

Electrical impedance tomography is a nondestructive imaging modality in which the internal resistivity distribution is reconstructed based on the injected currents and measured voltages inside a domain of interest. In this paper, an adaptive threshold value based region of interest (ROI) method is proposed to improve the spatial resolution of reconstructed images as well as to reduce the computational time of the inverse problem. Adaptive threshold value is calculated by INTERMODES method and ROI is determined from the domain based on this value. Moreover, the computational domain of image reconstruction is restricted within a ROI and iterative Gauss-Newton method is employed to estimate the resistivity distribution. To evaluate the performance of the proposed method, numerical experiments have been performed and the results are analyzed.

키워드

참고문헌

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