서지주요정보
두 지하 시추공에서 현장 측정한 전자파로부터 유전율과 도전율의 단층 영상 구현 = Undergound cross-borehole complex permittivity tomogram reconstructed from in situ measured electromagnetic fields
서명 / 저자 두 지하 시추공에서 현장 측정한 전자파로부터 유전율과 도전율의 단층 영상 구현 = Undergound cross-borehole complex permittivity tomogram reconstructed from in situ measured electromagnetic fields / 박성길.
저자명 박성길 ; Park, Seong-Kil
발행사항 [대전 : 한국과학기술원, 1998].
Online Access 원문보기 원문인쇄

소장정보

등록번호

8009222

소장위치/청구기호

학술문화관(문화관) 보존서고

DEE 98044

휴대폰 전송

도서상태

이용가능

대출가능

반납예정일

초록정보

Detection of isolated target such as underground tunnel located deeply may be possible by the cross-borehole or the single borehole measurements. In situ conductivities(σ) and permittivities(ε) of the underground geometry may be obtained by three borehole measurements; one for the transmitting(source) antenna and the others for the receiving antenna picking up the scattered fields at two different distances. By taking the division of these two fields, one may obtain the permittivity and the conductivity from the ratio of the amplitudes and the difference of the phases. Multi-frequency averaging of these permittivities and conductivities smooths out not only the dispersive characteristics but also the rapid fluctuations across the planar discontinuities such as cracks and faults. It is shown by the two dimensional simulations that cracks and faults may be identified by the back projection of the multi-frequency averaged σ and ε. The isolated targets such as the air tunnel, however, produces highly fluctuating interference fringes of σ and ε at the target, even with the multi-frequency averaging. After the identifying of the isolated target from the interference fringing area and by defining the region of reconstruction, one may reconstruct the isolated target by using the iterative inversion method. The two-dimensional numerical simulation shows that the successful reconstruction of the air tunnel is possible. It is shown here that the tomogram of σ and ε in the cross section covered by two boreholes is successfully obtained from the in situ data measured by Ra-Geovis. One may identify the fluctuating interference-fringe area from this three-dimensional measured data. The reconstruction of this isolated air tunnel requires larger computer capability and its reconstruction is proceeded. The tomogram obtained from this three-dimensional measurement gives acceptable distribution of σ and ε of the background medium.

서지기타정보

서지기타정보
청구기호 {DEE 98044
형태사항 iv, 159 p. : 삽도 ; 26 cm
언어 한국어
일반주기 저자명의 영문표기 : Seong-Kil Park
지도교수의 한글표기 : 나정웅
지도교수의 영문표기 : Jung-Woong Ra
학위논문 학위논문(박사) - 한국과학기술원 : 전기및전자공학과,
서지주기 참고문헌 : p. 148-159
주제 지하 시추공
유전율 단층 영상
반복 역산란 방법
땅굴 탐지
Underground cross-borehole
Permittivity tomogram
Iterative inversion method
Tunnel detection
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