http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
단일 주파수 시간조화 신호원을 사용한 도체기둥의 incoherent 단면영상법
강진섭,라정웅 대한전자공학회 1998 電子工學會論文誌, D Vol.d35 No.1
In this paper, an incoherent imaging of a conducting cylinder illuminated by the single-frequency time-harmonic plane wave is obtained via the back-projections of the intensity patterns of the forward total electric field scattered from this object in the circular rotational measurement configuration. The pheonmenon that interference fringes generated in the itesity patterns is removed in the back-projection process is interpreted numerically. This imaging method is validated by imagining conducting circular cylinders and the conditions to ge beter image are investigated.
Wiener-Hopf 적분방정식으로부터 파수영역에서의 쌍적분 방정식 유도에 관한 검토
하헌태,라정웅 대한전자공학회 1998 電子工學會論文誌, D Vol.d35 No.6
Wiener-Hopf 적분방정식으로부터 경계면 위의 전체파를 미지수로 하는 파수영역에서의 쌍적분 방정식을 얻는 기존의 유도과정을 검토하였다. 이러한 기존의 유도 과정은 결국 Wiener-Hopf 적분방정식으로부터 Helmholtz-Kirchhoff 적분방정식을 유도하는 과정임을 해석적으로 보였다. The derivation of the dual integral equation in the spectral domain, which has total fields of the interfaces as unknowns, is investigated. It is analytically shown that the derivation of the dual integral equation is equivalent to deriving the Helmholtz-Kirchhoff integral equation from the Wiener-Hopf integral equation.
주파수평균된 전계전력패턴을 사용한 high-contrast 원기둥 공동의 incoherent 영상법
강진섭,라정웅 대한전자공학회 1998 電子工學會論文誌, D Vol.d35 No.2
In this paper, an incoherent imaging of a high-contrast cylindrical cavity illuminated by the time-harmonic cylindrical wave is obtained ia the back-projections of he incoherent intensity patterns, which si acquired by averaging out the multi-frequency intensities of the total electric field scattered from this object in the cross-borehole measurement configuration. Multi-freuqncy effect is shown numerically and is intepreted analytically by the mutual coherence function defined in the is frequency domain. This imaging method is validated by imaging high-contrast cylindrical cavidities and the conditions to get better image are investigated.
주창성,라정웅,신상영,Ju, Chang-Seong,Ra, Jeong-Ung,Sin, Sang-Yeong 대한전자공학회 1981 전자공학회지 Vol.18 No.5
직각 쐐기는 유전체에 평면 전자파가 입사할때 일어나는 산란파에 대한 점근해를 구하였다. 산란파는 유전체경계면으로부터 반사된 파 및 고절된 파와 유전체 끝 모서리로부터 회석된 도간면파로 구성하였다. 모서리에서 회절된 전제는 물리광학 근사법에 의한 해에 교정항을 더하여 구하였으며, 이 교정 전계는 수치 계산에 의하여 풀 수 있는 이중 급수 방정식으로부터 구하였다. 구해진 점근해의 유효성은 유전체의 상대 유전률 ε의 값이 -에 갈때와 1에 가까운 값을 가질때의 두 극한치에서 검토 되었다. ε이 작을때는 Rawlins이 구한 ε Neumann계수해의 계산 결과와 같았으며, ε이 ∞에 접근할때 모서리의 회절 패턴은 도체 모서리의 회절패턴에 접근함을 보일 수 있다. An asymptotic solution of electromagnetic waves scattered by a right-angled dielectric wedge for plane wave incidence is obtained. Scattered fields are constructed by waves reflected and refracted from dielectric interfaces (geometric-optical fields) and a cylindrical wave diffracted from the edge. The edge diffracted field is obtained by adding a correction to the edge diffraction of physical optics approximation, where the correction field is calculated by solving a dual series equation amenable to simple numerical calculation. Validity of this result is assured by two limits of relative dielectric constant $\varepsilon$ of the wedge. The total asymptotic field calculated results in a Rawlins' Neumann series solution for small $\varepsilon$, and the edge diffraction pattern is shown to approach that of a perfectly conducting wedge for large $\varepsilon$. Calculated field patterns are presented and the accuracy of physical optics approximation is discussed.
다중주파수 시간좌화신호를 사용한 도체기중의 초고주파 incoherent 영상:Part I - 다중주파수 시간좌화신호를 사용한 incoherent 전력패턴
강진섭,라정웅 대한전자공학회 1996 전자공학회논문지-B Vol.b33 No.2
A microwave incoherent imaging method for a conducting cyliner by using multi-frequency tiem-harmonic field is presented in this study. In this paper, an incoherent intensity pattern of th econducting cylinder is obtained by averagin gout the multi-frequency intensities of the coherent field such as the time-harmonic field scattered from this cylinder. This phenomenon is hsown numerically in scattering by a conducting circular cylinder illuminated by the time-harmonic plane wave, and is interpreted analytically by the mutual coherence functon defined as a frequency-averaged intensity of the time-harmonic fields in th frequency domain.
다중주파수 시간조화신호를 사용한 도체기둥의 초고주파 incoherent 영상 : Part II - 도체기둥의 초고주파 incohernet 영상
강진섭,라정웅 대한전자공학회 1996 전자공학회논문지-B Vol.b33 No.2
In the previous paper of this study, an incoherent intensity pattern of a conducting cylinder is obtained by averaging out the multi-frequency intensities of the time-harmonic fields scattered from this cylinder. in this paper, an incoherent imaging of a conducting cylinder is obtained via the back-projection of the incoherent intensity patterns calculated from the circular rotational measurement configuration. This imaging method is vlaidated by imaging a conducting circular and a conducting elliptic cylinder and the measurement conditions to get better image are investigated.
지표면 위에 한쪽 면이 도체로 된 손실 유전체 슬랩 속의 다이폴 전원에 의한 동일면상의 전계
박동국,라정웅 대한전자공학회 1996 전자공학회논문지-A Vol.33 No.12
An electric field induced by a point dipole soruce within a conductor-backed lossy dielectric slab above the earth is calculated by anumerical method. the calcualtion is peformed on the plane which is parallel to the conductor plane and containing the point dipole soruce. Computed S$_{21}$ values of two parallel planar dipole antennas and two collinear planar dipole antennas are compared against each other, as well as the electic field magnitudes in those arrangements.