• 제목/요약/키워드: vertical alignment

검색결과 335건 처리시간 0.024초

Liquid crystal alignment on rubbed self-assembled monolayers with fluorinated alkyl chain

  • Oh, Chan-Woo;Hwang, Seok-Gon;Park, Sang-Geon;Park, Hong-Gyu
    • 한국정보전자통신기술학회논문지
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    • 제11권6호
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    • pp.671-677
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    • 2018
  • In this paper, we investigated the vertical alignment characteristics of liquid crystals (LCs) on fluorinated self-assembled monolayers (FSAMs). For comparison, a commercialized homeotropic polyimide (PI) layer was used as an LC alignment layer. We confirmed the successful deposition of FSAMs and the change of FSAMs before and after rubbing treatment through contact angle measurement and atomic force microscopy. The optical transmittance spectrum of the FSAMs is similar to that of the homeotropic PI layer, which is a superior optical characteristic applicable to LC devices. When FSAMs were applied to the vertically aligned (VA) LC cell, uniform and vertical LC alignments were achieved. In addition, the voltage-transmittance characteristic of VA LC cell with FSAMs was superior to that of VA LC cell with the conventional homeotropic PI layers. These results indicate that the FSAMs are suitable as the homeotropic LC alignment layer for enhanced LC devices.

수직 광폴리머를 이용한 새로운 MVA 셀 (New MVA Cell Using a Homeotropic Photopolymer)

  • 황정연;서대식
    • 한국전기전자재료학회논문지
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    • 제14권1호
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    • pp.54-57
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    • 2001
  • We have developed a new multidomain vertical-alignment (MVA) mode using a homeotropic photopolymer that provides a wider viewing angle for nematic liquidcrystal (NLC) with negative dielectric anisotropy. Good voltage-transmittance curves for he new MVA cell using the homeotropic photopolymer were observed. The viewing angle of the new MVA cell using the homeotropic photopolymer was wider than that of the conventional VA cell. The wide viewing angle using the new MVA cell is attributable to 4-domain by the ribs with UV exposure on the photopolymer.

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Effects of Vertical Alignment of Leg on the Knee Trajectory and Pedal Force during Pedaling

  • Kim, Daehyeok;Seo, Jeongwoo;Yang, Seungtae;Kang, DongWon;Choi, Jinseung;Kim, Jinhyun;Tack, Gyerae
    • 한국운동역학회지
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    • 제26권3호
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    • pp.303-308
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    • 2016
  • Objective: This study evaluated the vertical and horizontal forces in the frontal plane acting on a pedal due to the vertical alignment of the lower limbs. Method: Seven male subjects (age: $25.3{\pm} 0.8years$, height: $175.4{\pm}4.7cm$, weight: $74.7{\pm}14.2kg$, foot size: $262.9{\pm}7.6mm$) participated in two 2-minute cycle pedaling tests, with the same load and cadence (60 revolutions per minute) across all subjects. The subject's saddle height was determined by the height when the knee was at $25^{\circ}$ flexion when the pedal crank was at the 6 o'clock position (knee angle method). The horizontal force acting on the pedal, vertical force acting on the pedal in the frontal plane, ratio of the two forces, and knee range of motion in the frontal plane were calculated for four pedaling phases (phase 1: $330{\sim}30^{\circ}$, phase 2: $30{\sim}150^{\circ}$, phase 3: $150{\sim}210^{\circ}$, phase 4: $210{\sim}330^{\circ}$) and the complete pedaling cycle. Results: The range of motion of the knee in the frontal plane was decreased, and the ratio of vertical force to horizontal force and overall pedal force in the complete cycle were increased after vertical alignment. Conclusion: The ratio of vertical force to horizontal force in the frontal plane may be used as an injury prevention index of the lower limb.

종곡선/평면곡선 경합 시 승차감을 고려한 선형최적화에 관한 연구 (A Study on the Optimization of the Alignment Considering the Ride Comfort in the Case of the Superimposition of Vertical and Horizontal Curves)

  • 엄주환;양신추;최일윤
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.1943-1950
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    • 2010
  • Superimposition of horizontal and vertical curves may hamper the ride comfort and the running stability of train and largely affect the maintenance cost. However, in many cases, it's not easy to make a track plan because of the fixed points (bridge, tunnel, turnout, catenary system, etc.) to be avoided due to the geographic conditions or to be passed for utilization of existing structures. In this study, when the horizontal and vertical curves are superimposed, in order to optimize the horizontal curve in aspect of the ride comfort, the object function $P_{CT}$ was developed and verified by vehicle dynamic analysis. Also, the solution algorithm for simplified evaluation method was presented.

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Liquid Crystal Alignment on the SiC Thin Film by the Ion Beam Exposure Method

  • Park, Chang-Joon;Hwang, Jeoung-Yeon;Kang, Hyung-Ku;Kim, Young-Hwan;Seo, Dae-Shik;Ahn, Han-Jin;Kim, Kyung-Chan;Kim, Jong-Bok;Baik, Hong-Koo
    • Transactions on Electrical and Electronic Materials
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    • 제6권1호
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    • pp.22-24
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    • 2005
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of the SiC (Silicon Carbide) thin film. The SiC thin film exhibits good chemical and thermal stability. The good thermal and chemical stability makes SiC an attractive candidate for electronic applications. A vertical alignment of nematic liquid crystal by ion beam exposure on the SiC thin film surface was achieved. The about $87{\circ}$ of stable pretilt angle was achieved at the range from $30{\circ}$ to $45{\circ}$ of incident angle. The good LC alignment is maintained by the ion beam alignment method on the SiC thin film surface at high annealing temperatures up to $300{\circ}C$.

Effects of Pilates Reformer Exercise on Standing Postural Alignment

  • Sim, Gyeong Seop;Shin, Ho Jin;Kim, Shin Young
    • The Journal of Korean Physical Therapy
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    • 제33권2호
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    • pp.76-83
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    • 2021
  • Purpose: This study examined the effects of applying the Pilates reformer exercise to 17 adult women on the alignment of the standing posture. Methods: The subjects performed a Pilates reformer exercise for 60 minutes a day, three times a week, for a total of eight weeks. The Pilates reformer exercise consisted of five types: 1) lower and lift, 2) hundred, 3) plow, 4) airplane, and 5) twist. The standing posture alignment in the sagittal and frontal planes was measured using exbody 9100MOMI musculoskeletal analysis equipment. Results: A comparison of before and after the exercise using paired t-test revealed a significant decrease in the difference between the horizontal inclination and the vertical height that approached zero after the intervention in the frontal plane of anterior and posterior standing postures (p<0.05), and the lateral standing posture in the sagittal plane. In addition, the difference between the horizontal inclination and the vertical height decreased and approached zero after the intervention (p<0.05). Conclusion: The Pilates reformer exercise had a positive effect on the alignment of the standing posture.

데오도라이트를 이용한 위성체 얼라인먼트 측정에 관한 연구 (A Study on Spacecraft Alignment Measurement with Theodolite)

  • 윤용식;이동주
    • 한국공작기계학회논문집
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    • 제12권6호
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    • pp.64-70
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    • 2003
  • A measurement of spacecraft alignment is an important process of spacecraft assembly, integration and test because it is necessary that a ground station controls the precise positions of on-orbit spacecraft by using the alignment data of attitude orbit control sensors(AOCS) on spacecraft. In addition, accuracy of spacecraft alignment requirement is about $0.1^{\circ}$~$0.7^{\circ}$. The spacecraft alignment is measured by autocollimation of theodolite. This paper describes the measurement principle and method of spacecraft alignment. The result shows that all of the AOCS on the spacecraft are aligned within the tolerance required through the alignment measurement.

전기적 편광 조절형 카메라를 위한 수직 배향형 액정 소자 연구 (A study on vertical alignment liquid crystal devices for electrically polarization controlled camera)

  • 이나경;안현식;김성민;김민상;박승서;최윤석
    • 전기전자학회논문지
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    • 제27권4호
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    • pp.512-517
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    • 2023
  • 본 연구에서는 액정에 인가되는 전압을 조절하여 편광을 조절할 수 있는 액정 기반 편광 조절 기술을 폐쇄회로 텔레비전(CCTV)에 적용하여 사용자가 원하는 각도의 편광만을 투과시킬 수 있는 시스템을 제안한다. 기존의 편광필름이 적용된 CCTV는 역광 보정 기능에 치중되어 있기 때문에 편광을 제어할 수 없어 수면에서 반사된 빛이나 차량에서 반사된 하이라이트가 피사체 식별을 방해한다. 그러나 Vertical Alignment 모드를 사용하면 전기적으로 편광을 조절할 수 있기 때문에 사용자가 원하는 각도의 편광만 투과시켜 반사되는 하이라이트를 제거할 수 있다. 이 기술을 사용하여 얻은 이미지들은 컴퓨터 소프트웨어에 의해 최적의 이미지로 도출하였다. 편광 각도와 투과율, 편광 속도를 전기적으로 제어할 수 있는 액정 편광 패널을 편광 폐쇄회로 텔레비전에 적용하여 기존 CCTV에서의 피사체 식별을 개선하였다.

위성 탑재 센서의 정렬 측정 및 보정에 관한 연구 (A Study on Alignment Measurement and Compensation for Spacecraft Sensors)

  • 이병기;김영윤;윤용식
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.537-540
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    • 2005
  • The attitude control, sensors and camera installed on the spacecraft should be located according to the system alignment requirement. The alignment measurement requirement accuracy for the sensors should be below $\pm$0.1. Therefore, Alignment Measurement System which is combined theodolite, Rotating table and digital inclinometer etc., should be used. As the measurement accuracy is required very precise, the appropriate measurement procedure and alignment angle measurement, calculation and shimming work should is accomplished. Consequently, this paper is accomplished the works to align the measurement requirement accuracy throughout alignment measurement and shimming work of installed module and sensor

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수평 배향막을 이용한 내장형 위상지연 박막의 액정 배향 효과 (The liquid crystal alignment effect of in-cell retarder using homogeneous alignment layer)

  • 최민오;임영진;이승희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.449-450
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    • 2005
  • Alignment characteristic of liquid crystal (LC) on in-cell retarder which is composed of reactive mesogens has been tested. The in-cell retarder which is polymerized on top of the homogeneous alignment layer (AL) has an optic axis along the rubbing direction of the homeogenous AL and does show good alignment effect of the LC without showing any defects, which possibly allows a skip of another AL on the in-cell retarder that was required conventionally to control alignment of the LC. However, the measured pretilt angle is only 0.04 degree so that disclination lines are generated for a cell that uses the in-cell retarder as an AL when the LC is tilted upward by a vertical electric field.

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