• 제목/요약/키워드: Oblique Angle

검색결과 411건 처리시간 0.024초

골간부 사형 절골술을 이용한 소건막류의 치료 (Treatment of Bunionette Deformity with Diaphyseal Oblique Osteotomy)

  • 안재훈;김하용;강종원;최원식;김용인
    • 대한족부족관절학회지
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    • 제12권1호
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    • pp.31-35
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    • 2008
  • Purpose: The authors intended to evaluate the results of symptomatic bunionette treated with a diaphyseal oblique osteotomy. Materials and Methods: Nine patients were followed for more than 1 year after diaphyseal oblique osteotomy for a bunionette deformity with plantar callosity. The mean age was 43 years (23-69 years), and the mean follow-up period was 27 months (12-70 months). As a combined disorder, 7 patients had hallux valgus, for which 3 distal metatarsal oteotomies, 3 proximal osteotomies, and 1 double osteotomy were performed. Clinically, preoperative and postoperative AOFAS MP-IP scale, patient's satisfaction, postoperative complications were analyzed. Radiologically, the 4th intermetatarsal angle and the 5th metatarso-phalangeal angle were analyzed. Results: Clinically, AOFAS MP-IP scale was increased from 59 points preoperatively to 93 points postoperatively, and all patients were satisfied with the results. The plantar callosity had all disappeared at the final follow up. The 4th intermetatarsal angle was decreased from $12.6^{\circ}$ preoperatively to $4.3^{\circ}$ postoperatively, and the 5th metatarsophalangeal angle was decreased from $21.9^{\circ}$ preoperatively to $2.4^{\circ}$ postoperatively. There were no significant postoperative complications. Conclusion: Diaphyseal oblique osteotomy of the 5th metatarsal appears to be safe and satisfactory procedure for the treatment of a symptomatic bunionette with plantar callosity.

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자기공명영상을 이용한 금속전극의 정확한 위치 결정 (Accurate Localization of Metal Electrodes Using Magnetic Resonance Imaging)

  • 조은혜;김민호;하윤;김동현
    • Investigative Magnetic Resonance Imaging
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    • 제15권1호
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    • pp.11-21
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    • 2011
  • 목적: 금속전극은 MRI 안에서 자기장의 왜곡을 일으켜 영상에 인공물이 나타난다. 본 논문에서는 전극이 B0와 수직으로 놓였을때 자기장 패턴의 특성을 이용하여 oblique-view angle imaging 방식을 통해 전극의 정확한 위치를 결정하는 방법을 제시하고자 한다. 대상 및 방법: 다양한 직경과 자화율을 가진 금속 전극모델의 시뮬레이션을 통하여 전극으로 인해 왜곡되는 field map의 양상을 파악하고 해상도에 따른 turbo spin-echo (TSE) 영상의 왜곡패턴을 분석하여 일반적인 영상기 법($90^{\circ}$ view)과 $45^{\circ}$ oblique-view에서의 위치 추정 기준을 마련하였으며 3.0T 임상용 장비에서 실제 전극의 TSE영상을 획득하여 시뮬레이션과 대조 검증하였다. 상대적으로 자기장의 왜곡에 민감한 gradient-refocused echo (GRE)시퀀스에서는 위상 영상을 이용해 위치를 추정하였다. 결과: 금속전극이 B0와 수직일 때 전극을 통과하는 $45^{\circ}$ 선상에서는 자기장 패턴의 변화가 매우 적었다. TSE 시퀀스의 경우 $45^{\circ}$ oblique-view 영상에서는 자화율의 크기에 관계없이 위치 추정기준이 잘 들어 맞았으며 자기장 왜곡에 의한 픽셀이 동양상이 양방향 대칭적으로 일어나므로 해상도가 낮은 경우에도 정확한 위치 추정이 가능하였다. 또한 GRE 시퀀스를 사용하였을때 $45^{\circ}$ oblique-view에서는 위상의 극성이 변화하는 선이 직교좌표계와 일치하기 때문에 일반적 방법보다 위치추정이 용이하였다. 결론: 시뮬레이션과 실제영상을 이용하여 일반적인 $90^{\circ}$ view에서보다 $45^{\circ}$ oblique-view에서 금속전극의 위치추정이 용이함을 확인하였다. 이는 전기 생리학적인 뇌연구 및 뇌수술 등을 MRI로 모니터링 하는데 적용 가능할 것으로 기대된다.

Optical Simulation of Viewing Angle Property of Biaxial Nematic Bent-Core Liquid Crystal

  • Yang, Seungbin;Lee, Ji-Hoon
    • Journal of the Optical Society of Korea
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    • 제20권4호
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    • pp.510-514
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    • 2016
  • The conventional liquid crystal displays (LCDs) have been using optically uniaxial liquid crystal (LC) medium and this often causes a significant image change at oblique viewing angles. We simulated the viewing angle properties of the biaxial nematic (Nb) phase of a bent-core liquid crystal (BLC) and compared the results with the vertically aligned (VA)- and the in-plane switching (IPS)-LCDs. The Nb phase of the BLC showed a smaller transmittance at the dark state as well as a greater contrast ratio at wide viewing angle. The viewing angle property of the Nb-mode without any compensation film was slightly superior to the IPS-mode with the compensation films eliminating the decross of the polarizers at oblique viewing angle.

경사진 자외선조사를 이용한 셀의 프리틸트각의 입사각도 의존성 (Liquid crystal alignment and pretilt angle generation using oblique UV light irradiation on polymer surface)

  • 서대식;한정민;박두석;박태규;황율연
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.267-270
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    • 1998
  • In this study, we investigated the generation of pretilt angle for nematic liquid crystal (NLC) in a cell with oblique non-polarized ultraviolet (UV) light irradiation on polyimide (PI) surfaces. It was found that the monodomain alignment of the NLC is obtained in a cell with an angle of incidence of 70∼85$^{\circ}$on PI surface. We consider that the monodomain alignment of NLC is attributed to anisotropic dispersion force effect due to Photo-depolymerization of polymer on PI surfaces. Also, pretilt angle of NLC is generated about 3$^{\circ}$ with an angle of incidence of 70∼75$^{\circ}$. It is considered that the pretilt angle generation in NLC is attributed to interaction between the LC molecules and the polymer surfaces.

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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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밸브 없는 양방향 피에조 마이크로펌프의 유동해석 (A Numerical Study on Flow Analysis of a Valveless Bidirectional Piezoelectric Micropump)

  • 이상혁;허인영;허남건
    • 한국유체기계학회 논문집
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    • 제11권3호
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    • pp.14-21
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    • 2008
  • A numerical simulation on the flow field of a valveless bidirectional piezoelectric micropump has been performed. In this type of micropump, the oscillation of the piezoelectric diaphragm generates the blowing and suction flow through the oblique channel from the pumping chamber. The angle between the oblique and main channel causes the variation of flow distribution through upstream and downstream channels in suction and blowing modes. In the suction flow mode, the working fluid flows from both the upstream and downstream of the main channel to the pumping chamber through the oblique channel. However, in the blowing flow mode, the fluid pushed out of the pumping chamber flows more toward the downstream of the main channel due to the inertia of the fluid. In the present study, the effects of geometries such as the angle of oblique channel and the shape of main channel on the flow rate of the up/downstream were investigated. The flow rate obtained from the pump and the energy required to the pump were also analyzed for various displacements and frequencies of the oscillation of the diaphragm.

연직사진과 경사사진을 함께 이용한 UAV 사진측량의 정확도 평가 연구 (A Study on the Accuracy Evaluation of UAV Photogrammetry using Oblique and Vertical Images)

  • 조정민;이종석;이병길
    • 한국측량학회지
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    • 제39권1호
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    • pp.41-46
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    • 2021
  • 무인항공기를 이용한 데이터 취득이 널리 활용되면서 무인항공기를 이용한 사진측량의 정확도를 높일 수 있는 방안의 하나로 항공삼각측량의 번들 조정에 연직사진과 경사사진을 같이 사용하는 방법이 제시되고 있다. 본 연구에서는 사진측량의 정확도를 높이는 데 적합한 방법을 찾기 위해 촬영 각도를 달리하여 촬영한 경사사진을 조정하는 경우와 촬영 각도가 다른 경사사진을 연직사진과 동시에 조정하는 경우의 정확도를 비교하였다. 연구결과 입력되는 경사사진의 경사가 커질수록 검사점의 오차가 줄어드는 것으로 나타났으며, 특히 연직사진과 경사사진을 같이 사용할 때, 경사사진의 경사가 클수록 높이 오차가 크게 줄어드는 것으로 나타났다. 현행 『항공사진측량 작업규정』에서는 연직사진의 GSD (Ground Spatial Distance)와 동일한 RMSE (Root Mean Square Error)를 요구하고 있다. 촬영각도 50°의 경사사진을 이용할 때 이 기준에 거의 근접한 결과를 얻을 수 있었고, 연직사진과 50°의 경사사진을 동시에 조정한 경우 작업규정을 만족시킬 수 있었다. 본 연구 결과를 활용하면 무인항공기에 탑재된 저가의 사진기를 이용하는 사진측량이 더욱 활발해 질 수 있을 것으로 기대된다.

Oblique Single-Cut Rotation Osteotomy for Correction of Femoral Varus-Torsional Deformities in 3D-Reconstructed Canine Bone Models

  • Kim, Hyeon-Ho;Roh, Yoon-Ho;Lee, Je-Hun;Jeong, Jae-Min;Jeong, Seong Mok;Lee, Hae Beom
    • 한국임상수의학회지
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    • 제37권4호
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    • pp.180-184
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    • 2020
  • The purpose of this study was to report the reliability and validity of oblique single-cut rotation osteotomy (OSCRO) in 3D-reconstructed canine bone models with femoral varus and torsional deformities. A healthy adult male beagle was recruited to create a 3D bone model, and this bone model was modified by using a 3D program. Fifteen bone models were constructed for this study. OSCRO simulation was performed in accordance with the plan after printing using a 3D printing machine. The anatomical lateral distal femoral angle (aLDFA), anteversion angle (AA), anatomical caudo-distal femoral angle (aCdDFA), mechanical caudo-distal femoral angle (mCdDFA) and pre- and postoperative bone length were calculated. There were no significant differences between the target values and postoperative values. In addition, the difference between pre- and postoperative bone length was small (p = 0.001). Our findings suggest that OSCRO could be an effective surgical option for MPL with bone deformities in small-breed dogs that often undergo conventional distal femoral osteotomy.

지지면과 무릎관절 각도에 따른 교각운동이 복부근육의 두께에 미치는 영향 (Effect of Bridge Exercise on the Thickness of Abdominal Muscle according to Support and Knee Angle)

  • 문달주;박재철;최석주
    • 대한물리치료과학회지
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    • 제25권3호
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    • pp.25-31
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    • 2018
  • Background: The purpose of this study was to find out how changes in knee angles in stable and unstable support surfaces affect the muscle thickness of core muscles. Methods: The subjects of this study were 25 male adult. Each knee angle of 120, 90 and 60 degrees, they were performed bridge exercise on the stabilized surface and on the unstable support surface using TOGU, and measured the muscle thickness of the external and internal oblique muscle and the abdominal muscles through ultrasound images. Results: There was no significant difference between the thickness of the rectus abdominis and the internal oblique muscle depending on the support surface and the knee joint bending angles. However, there was a significant difference between the external oblique muscle and the transverse abdominis muscle by knee joint flexion angle. Conclusion: While the muscle thickness of the core muscle was not significantly affected by each support surface during the bridge exercise, there were significant changes in the core muscle as a result of changes in knee angle.

폴리이미드막 표면에 직선 편광된 UV광 조사에 의한 프리틸트각 발생과 전기광학특성 (Pretilt Angle Generation and EO Performance in MLC with Polarized UV Light Irradiation Polyimide surface)

  • 서대식;이정호;이창훈
    • 한국전기전자재료학회논문지
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    • 제11권10호
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    • pp.878-884
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    • 1998
  • We have investigated that the monodomain alignment of nematic liquid crystal (NLC) is obtained with polarized ultraviolet(PUV) light irradiation on polyimide (PI) surface. The LC alignment capability increases with increasing the UV light irradiation time. The polarized UV light irradiation on oblique angle of 60。 irradiated on PI surface rotated by 90。 at 10 min. after being normally irradiated on PI surface at 30 min., the generated pretilt angle of NLC is about 2.5。. The pretilt angle of NLC is attributed to the interaction between the LC molecules and the asymmetric triangular structure of polymer surface due to photo-depolymerization of polymer with the oblique UV light on PI surface. The voltage -transmittance and response time characteristics of photo-aligned twisted nematic (TN)-LCD with UV light irradiation time 60 min. were almost same in comparison with the rubbing-treated TN-LCD.

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