• Title/Summary/Keyword: Oblique Incidence

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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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    • v.16 no.1
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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.

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

  • Jeong, Hyun-Jo
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.2
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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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Oblique Incidence Technique for Ultrasonic Nonlinear Characterization in SUS316L Alloy (SUS316L 강의 초음파 비선형 특성평가를 위한 경사입사기법)

  • Baek, Seung-Hyun;Lee, Tae-Hun;Kim, Chung-Seok;Jhang, Kyung-Young
    • Journal of the Korean Society for Nondestructive Testing
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    • v.30 no.4
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    • pp.345-351
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    • 2010
  • The oblique incidence technique for ultrasonic nonlinear characterization was studied in stainless steel 316L alloy subjected to high cycle fatigue. A dog-bone plate specimen was prepared to make different faitgue-driven deformation at each position where the stress concentration could occur in the middle of specimen. In addition to the normal transmission technique, the oblique incidence technique which is newly suggested in this study, was used to measure ultrasonic nonlinear parameter. The fatigued specimen shows higher ultrasonic nonlinear parameter than the virgin specimen for both techniques. Ultrasonic nonlinear parameter highly increases in the middle of test specimen where the stress concentration existes. Relative nonlinear parameter has strong correlation with fatigue damage. Consequently, the oblique incidence technique with longitudinal wave can be potential to characterize high cycle fatigue damage.

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

  • Nam, Tae-Hyung;Kim, Chung-Seok;Lee, Tae-Hun;Jhang, Kyung-Young;Kim, Noh-Yu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.9
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    • pp.1113-1118
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    • 2011
  • In order to evaluate the characteristics of solid-solid contact interfaces, reflection or transmission techniques involving normal-incidence longitudinal waves are generally used. However, these normal-incidence techniques are of limited use in field applications such as in the inspection of welded parts. The oblique-incidence ultrasonic technique may be an alternative for overcoming these problems. However, in this technique, the mode conversion at the contact interfaces should be taken into account along with the normal and tangential interface stiffness. In this study, we have suggested a theoretical model for obliqueincidence ultrasonic waves at the contact interfaces and analyzed their reflection and transmission characteristics. Experimental results showed that the measured reflection coefficient and second harmonic wave agreed well with the suggested theoretical model. Consequently, the oblique-incidence technique can be a promising method for evaluating the characteristics of the contact interfaces.

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

  • 조웅희;고지환;조영기
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.2
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    • pp.238-252
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    • 1998
  • Diffraction anomalies in the periodic strip grating over a grounded dielectric layer are investigated for the plane wave incidence case of both arbitrary(oblique) incidence angle and arbitrary polarization by use of the spectral domain method combined with the sampling theorem. Some numerical results for the Bragg and Off-Bragg blazing phenomena for the cases of arbitrary incidence angle and polarization as well as TE and TM polarization are presented along with discussions on those phenomena.

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

  • 서대식;한정민;박두석
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.10
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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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Measurement of Oblique Incidence Reflection Coefficient Using Beamforming Method (빔형성 방법을 이용한 경사 반사계수 측정)

  • 주형준;강연준
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.13 no.6
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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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    • v.26 no.2
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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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    • v.35 no.4
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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.