• 제목/요약/키워드: Oblique incidence

검색결과 82건 처리시간 0.031초

Optical Modeling for Polarization-dependent Optical Power Dissipation of Thin-film Organic Solar Cells at Oblique Incidence

  • Kim, Jungho;Jung, Sungyeop;Jeong, Inkyung
    • Journal of the Optical Society of Korea
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    • 제16권1호
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    • pp.6-12
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    • 2012
  • We present the optical models and calculation results of thin-film organic solar cells (OSCs) at oblique incidence of light, using the transfer matrix method. The simple expression for the optical power dissipation is derived at oblique incidence for s- and p-polarized light. The spatial distribution of the electric field intensity, the optical power density, and the optical power dissipation are calculated in both s- and p-polarized light with respect to the incidence angle. We identify how the light absorption efficiency for p-polarized light becomes relatively larger than that for s-polarized light as the incidence angle increases.

초음파의 에너지속도와 위상속도의 주행시간 동시성과 이방성 재료의 탄성계수 결정 (Equivalence of the times of flight by ultrasonic energy and phase velocities and determination of the elastic constants of anisotropic materials)

  • 정현조
    • 한국정밀공학회지
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    • 제11권2호
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    • pp.95-103
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    • 1994
  • The purpose of this paper is to provide the experimenters who use the oblique incidence ultrasonic method for anisotropic elastic constants measurement eith some useful relations. In particular, the equivalence of the times of flight by the energy ad phase velocities, which is key to the oblique incidence method, is proved explicitly. This equivalence greatly simplifies the analysis of immersion measurement results. In oredr to correctly measure the transit time of an immersed sample using the oblique incidence, the receiving transducer should be shifted laterally, and an expression in given for this shift. A method for determining all nine elastic constants of an orthotropic material is briefly described and the measurement results are listed for SiC particulate reinforced A1 matrix composites.

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SUS316L 강의 초음파 비선형 특성평가를 위한 경사입사기법 (Oblique Incidence Technique for Ultrasonic Nonlinear Characterization in SUS316L Alloy)

  • 백승현;이태훈;김정석;장경영
    • 비파괴검사학회지
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    • 제30권4호
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    • pp.345-351
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    • 2010
  • 본 연구에서는 고주기 피로를 받은 SUS316L 강에서의 초음파 비선형 특성평가를 위한 종파 경사입사기법을 연구하였다. Dog-bone형의 판상시편을 준비하여 시편 중심부에서 응력집중이 되며 각 위치마다 피로 손상이 다르도록 제작하였다. 수직투과법 외에 본 연구에서 새로이 제안한 경사입사법을 이용하여 초음파 비선형 파라미터를 측정하였다. 두 기법 모두에서 피로 손상 전보다 고주기 피로 손상 후 초음파 비선형 파라미터가 높게 나타났다. 특히, 응력 집중을 받은 시편 중심부에서 크게 증가하였다. 상대적인 초음파 비선형 파라미터는 피로 손상과 밀접한 상관성을 보였으며 결과적으로 종파를 이용한 경사입사기법은 피로 손상을 평가하는데 효과적인 기법이라 할 수 있다.

고체-고체 접촉계면에서 경사입사 초음파의 반사·투과 특성 분석 (Reflection and Transmission Characteristics of Oblique-Incidence Ultrasonic Waves at Solid-Solid Contact Interfaces)

  • 남태형;김정석;이태훈;장경영;김노유
    • 대한기계학회논문집A
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    • 제35권9호
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    • pp.1113-1118
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    • 2011
  • 고체-고체 접촉계면의 특성을 평가하기 위하여 초음파 수직 입사에 의한 반사 투과법이 주로 이용되어왔다. 하지만 수직입사방법은 용접부 검사와 같은 현장적용에 한계가 있는 단점이 있다. 이러한 한계를 극복하기 위한 방법으로 초음파 경사입사법이 대안이 될 수 있다. 그러나 경사입사법의 경우, 초음파의 모드변환이 발생하고 수신신호는 접촉면의 수직 계면강성뿐만 아니라 수평 계면강성의 영향을 받으므로 이를 고려한 분석이 필요하다. 본 연구에서는 경사입사에 따른 접촉계면에서의 초음파 반사와 투과특성에 대한 이론적 모델을 제안하였다. 그리고 경사입사에 대한 초음파 반사율 및 2 차 고조파 측정실험 결과 이론적 예측과 잘 일치함을 확인하였다. 결과적으로 경사입사법은 접촉계면 특성평가를 위한 효과적인 기법이라 할 수 있다.

임의의 편파로서 비스듬한 각도로 입사하는 전자파의 경우에 대한 접지된 유전체층 위에 놓여있는 주기적인 스트립격자 구조에서의 특이한 회절현상 (Diffraction Anomalies on the Periodic Strip Grating over a Grounded Dielectric Layer in Case of Oblique Incidence and Arbitrary Polarization)

  • 조웅희;고지환;조영기
    • 한국전자파학회논문지
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    • 제9권2호
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    • pp.238-252
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    • 1998
  • 임의의 편파로서 비스듬한 각도록 입사하는 전자파의경우에 대한 접지돈 유전체층 위에 놓여있는 주기적인 스트립격자 구조에서의 특이한 희절현상을 샘플링 정리와 파수영역 방법을 사용하여 해석하였다. 수치적 결과는 임의의 편파와 TE 및 TM편파가 입사되는 경우에 대하여 각각 Bragg 및 Off-Bragg blazing현상을 확인하고 이에 관하여 논의하였다.

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경사진 자외선조사를 이용한 네마틱액정의 프리틸각의 발생 및 광배향 TN-LCD의 전기광학특성 (Pretilt Angle Generation of Photo-aligned TN-LCD Using Oblique Non-polarized UV Light Irradiation on Polymer Surface)

  • 서대식;한정민;박두석
    • 한국전기전자재료학회논문지
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    • 제11권10호
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    • pp.911-917
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    • 1998
  • In this paper, we have investigated the generation of pretilt angle for nematic liquid crystal (NLC) in a cell with oblique non-polarized ultraviolet(UV) light irradiation polyimide (PI) surface. It was found that the monodomain alignment of the NLC is obtained with an angle of incidence of 70∼85。 on PI surface. It is considered that the monodomain alignment of NLC is attributed to anisotropic of NLC is about 3。 with and angle of incidence of 70∼75。. Finally, we observed that the voltage-transmittance, response time, and voltage-holding-ratio(VHR) characteristics of photo-aligned twisted nematic(TN)-LCD with and angle of incidence of 85。 on PI surface were almost same compared to rubbing -treated TN-LCD.

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빔형성 방법을 이용한 경사 반사계수 측정 (Measurement of Oblique Incidence Reflection Coefficient Using Beamforming Method)

  • 주형준;강연준
    • 한국소음진동공학회논문집
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    • 제13권6호
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    • pp.438-444
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    • 2003
  • A method using beamforming algorithm has been developed to measure oblique incidence reflection coefficients of sound absorption materials. MUSIC(multiple signal classification) method detects the angles of incidence and reflection. By separating the incident and reflected waves using beamforming method, the reflection coefficient is calculated. Spatial smoothing technique Is also used to reduce the coherence between the incident and reflected waves. Numerical and experiment results are performed to verify the accuracy of proposed method.

Dynamic response of integrated vehicle-bridge-foundation system under train loads and oblique incident seismic P waves

  • Xinjun Gao;Huijie Wang;Fei Feng;Jianbo Wang
    • Earthquakes and Structures
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    • 제26권2호
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    • pp.149-162
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    • 2024
  • Aiming at the current research on the dynamic response analysis of the vehicle-bridge system under earthquake, which fails to comprehensively consider the impact of seismic wave incidence angles, terrain effects and soil-structure dynamic interaction on the bridge structure, this paper proposes a multi-point excitation input method that can consider the oblique incidence seismic P Waves based on the viscous-spring artificial boundary theory, and verifies the accuracy and feasibility of the input method. An overall numerical model of vehicle-bridge-soil foundation system in valley terrain during oblique incidence of seismic P-wave is established, and the effects of seismic wave incidence characteristics, terrain effects, soil-structure dynamic interactions, and vehicle speeds on the dynamic response of the bridge are analyzed. The research results indicate that with an increase in P wave incident angle, the vertical dynamic response of the bridge structure decreased while the horizontal dynamic response increased significantly. Traditional design methods which neglect multi-point excitation would lead to an unsafe structure. The dynamic response of the bridge structure significantly increases at the ridge while weakening at the valley. The dynamic response of bridge structures under earthquake action does not always increase with increasing train speed, but reaches a maximum value at a certain speed. Ignoring soil-structure dynamic interaction would reduce the vertical dynamic response of the bridge piers. The research results can provide a theoretical basis for the seismic design of vehicle-bridge systems in complex mountainous terrain under earthquake excitation.

Correction of Bilateral Tessier No. 2, 3, and 12 Facial Cleft with Anopthalmia

  • Moon, Seong-Yong;Kim, Seong-Gon;Park, Young-Ju;Park, Young-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제35권4호
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    • pp.243-247
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    • 2013
  • Oblique facial cleft is a rare congenital deformity. Its incidence has been reported as 0.24% of all reported cases of facial cleft. We report on a patient who had a left-sided oblique facial cleft with anopthamia, including lip and palate, nose alar base, and medial canthus. The patient also had a right-sided oblique facial cleft, which included lip and palate, nose alar base, medial canthus, and upper eye brow. Primary closure of the facial cleft was performed using multiple Z-plasty after excision of scar tissue.