• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.1075-1078
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• 1999

In this study, a new algorithm for canceling MRI artifacts through the translational motion of image plane is presented. Bloating is often makes problems in a clinical diagnosis. Assuming that the head moves up and down due to breathing, rigid translational motions in only y(phase encoding axis) direction is treated. First, we notice that the x directional motion corresponds to a shift of the x directional spectrum of the MRI signal, and the non zero area of the spectrum just corresponds to x axis projected area of the density function. So the motion is estimated by tracing the edges of the spectrum, and the x directional motion is canceled by shifting the spectrum in inverse direction. Next, the y directional motion is canceled using a new constraint, with which the motion component and the true image component can be separated. Finally, the effectiveness of this algorithm is shown by using a phantom with simulated motions.

• 대한전자공학회논문지SP
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• 제38권6호
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• pp.684-691
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• 2001

본 논문에서는 비디오 카메라를 통하여 획득한 연속적인 영상에서 사람의 머리를 인식하고 추적하는 시스템을 구현한다. 사람의 머리를 인식하기 위한 특징 벡터로서 얼굴 표면상의 특성인 사람의 피부색과 형태상의 특성인 타원 모델링을 이용한다. 또한 복잡한 배경으로부터 움직인 영역을 획득하기 위하여 시변 에지 검출 방법을 사용하고 획득된 영상에서 물체의 움직임을 판별하기 위하여 수직 투영 방법을 이용한다. 설정된 움직임 영역부분에 대하여 피부색을 갖고 있는 여러 개의 얼굴 후보영역을 설정하고 사람의 얼굴을 대표할 수 있는 타원 매핑을 적용하여 가장 최적으로 매핑되는 영역을 사람의 얼굴 부분으로 인식한다. 본 논문에서 제안한 방법은 사람 얼굴이 360도 회전하는 경우와 부분적으로 가려진 경우 그리고 좌우로 기울어진 경우에서도 우수한 성능을 보여주고 있다. 본 논문에서는 움직임 기반 추적 방법과 인식 기반 추적 방법을 이용하여 사람의 얼굴 부분이 빠르게 움직이는 경우에도 정확한 사람 얼굴 추적이 가능하도록 한다.

• Clinics in Shoulder and Elbow
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• 제10권2호
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• pp.183-189
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• 2007

서론: 상완골 두의 비 외상성 골괴사는 흔치 않은 질환으로 환자의 증상이 심하고 골두 함몰이 진행된 경우 인공관절 치환술의 적응증이 된다. 저자들은 상완골 두 비 외상성 골괴사 환자에 시행한 견관절 반 치환술의 단기 추시 임상결과를 보고하고자 한다. 재료 및 방법: 상완골 두의 비 외상성 골괴사 환자로 견관절 반 치환술을 시행 받았던 환자 중 12개월 이상 ($12{\sim}56$개월)추시 가능하였던 5명, 7견관절을 대상으로 수술 전, 후의 통증 변화, 견관절 운동범위 및 ASES 점수를 비교하였고, 술후 환자의 만족도를 조사하여 임상적 결과를 분석하였다. 결과: 골괴사의 유발원인으로는 알코올 4예, 스테로이드 투여에 의한 경우가 3예였다. 운동시 통증은 수술 전 평균 7.6점에서 수술 후 1.9점으로 감소되었고 관절운동 범위는 전방거상, 외전 및 외회전이 술 전 평균 각각 105.7도, 80.0도, 22.1도였고 술후 146.6도, 139.3도, 44.3도로 호전되었다. ASES 점수는 술 전 평균 39.0점이었고, 술후 평균 84.1점으로 호전되었다. 술후 환자의 만족도는 흡족 5예, 양호 2예이었다. 결론: 단기 추시 결과이지만 상완골 두 비 외상성 골괴사의 치료 방법으로 견관절 반 치환술은 통증의 감소와 견관절 운동범위를 개선시켜주고, 양호한 술 후 환자 만족도를 제공할 수 있는 수술 방법이라고 생각한다.

• Archives of Reconstructive Microsurgery
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• 제21권2호
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• pp.137-142
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• 2012

Purpose: To report the clinical and radiological result of the vascularized fibular epiphyseal transplantation in the treatment of humeral head deformity by septic arthritis Material & Methods: A 3 years old male who has humeral head deformity and bone defect by septic arthritis on neonatal period. We replaced bone defect as vascularized fibular epiphyseal transplantation and lengthened humerus shaft for humerus discrepancy. We followed it up for 14 years. Result: We saw the callus formation 2 months after surgery and obtained bone union, one year after surgery. The transplanted fibular bone got hypertrophy. We could check full range of motion on lt. shoulder and The bone deformity was not worsened and The graft did not displaced on last follow up. Conclusion: Humeral head reconstruction by vascularized fibular epiphyseal transplantation showed good clinical outcome.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 춘계학술대회 논문집
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• pp.410-415
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• 2004

Heavy-weight head slides may cause excessive inertia impact ＆ moment on the machine tool structure when they move or stop abruptly during operation. Consequently these inertia impact and unbalanced moment bring transient vibrations and rough sliding motions on the machine structure. Machine tool engineers have tried many kind of feed-slide designs in order to solve this problem; for example, the design optimization of the moving structure for minimum weight and maximum stiffness, box-in-box type slide design, and so on. In this article, force and moment equilibrium equations regarding to the inertia force ＆ moment were derived for each one of a mold M/C's head slides. Furthermore, five different design configurations of head slide assembly were reviewed for its design improvement regarding to force ＆ moment calculations and finite element structural analysis results.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1331-1334
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• 2008

In this paper, we developed a novel hyperreality display called the Head Dome Projector (HDP). The HDP is a head-mounted display consisting of a dome-shaped screen with a very small radius of 40 cm, a mobile projector with ultra-wide projection lens and LED light sources. The main feature of the HDP is very wide viewing angle of 160 degrees horizontally by 120 degrees vertically comparable to the human visual field of view without head tracking and 360 degrees by 360 degrees with head tracking. According to our subjective evaluation comparing the HDP with a flat-panel display (FPD), the HDP realizes hyperreality 2.5 points higher than that realized by an FPD in the case of ${\pm}5$ level evaluation for HD motion images.

• Clinics in Shoulder and Elbow
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• 제18권3호
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• pp.167-171
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• 2015

Humeral head chondrolysis has been widely reported as a devastating complication after arthroscopic shoulder surgery; however little is known about post-arthroscopic humeral head osteonecrosis. We experienced a 66-year-old female patient with rapidly progressive osteonecrosis of the humeral head only seven months after arthroscopic Bankart and rotator cuff repair. The patient had no systemic risk factors for osteonecrosis. A satisfactory result was achieved with reverse total shoulder arthroplasty for severe humeral head destruction and an irreparable massive rotator cuff tear. Shoulder surgeons should be aware of such severe complication, perform routine radiographs, and pay close attention to the presence of constant pain or loss of motion after arthroscopic shoulder surgery.

• 한국농공학회지
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• 제41권5호
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• pp.77-85
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• 1999

Irrigation pipeline systems have been recently adopted for irrigation purposes, which was thought to improve irrigation efficiencies. However, if hydraulic characteristics are not evaluated in designing , overpressure due to waterhammer may occur and result in serious problems. Therefore, in this study a model was formulated to simulate unsteady motion of water in a pipeline resulting from valve closure, the applicability of the model owas tested with fiedld data, and the results showed good agreement in maximum piezometric head. Also, simulated maximum piezometric head was compared with designed piezometric head computed by empirical method, and maximum piezometric head in a pipeline resulting from valve closure was simulated and analyzed with varing surge tank's position and diameter.

• 대한한방소아과학회지
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• 제22권1호
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• pp.149-162
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• 2008

Objectives The purpose of this study is to investigate that causes of motion sickness in oriental medicine. Methods The internal and external studies about motion sickness were searched Results and Conclusions The motion sickness is induced by conflict of balance system including vestibular, visual and proprioceptive system. The motion sickness is more common in female and in children between 2 and 12 years old. In western medicine, antihistamine and anticholinergic has been used for treatment of motion sickness, but these anti-motion sickness drug turn out to be not a perfect solution and have several side effects. On the other hands, In oriental medical terminology, there is no words equivalent to the "motion sickness", but we consider the motion sickness as state with dizziness, nausea and vomiting. The motion sickness can be induced by either internal or external causes and the internal causes can thought to be a constitutional factor of an individuals, and the general transportation can be an external cause. The important internal cause is a dysfunction of the spleen, stomch(脾胃不調), retention of phlegm and fluids(痰飮), and deficiency of the kidney jing(腎精不足). The wind(風) and fire(火) in the upper part of the body, especially in the head, also can be an important cause of the motion sickness.

• 대한후두음성언어의학회지
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• 제20권2호
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• pp.126-130
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• 2009

Arytenoid motion has long been recognized as complex. Misunderstandings about the specifics of arytenoid motion remain prevalent. The resultant misunderstandings have led to erroneous or suboptimal clinical approaches to the treatment of vocal fold immobility. A thorough understanding of the anatomy of the arytenoid and cricoid cartilages, the cricoarytenoid joint, and related ligaments, muscles, and other structures is essential in order to fully understand laryngeal motion disorders. Arytenoid motion occurs in three directions. Movements involving a change anteriorly and posteriorly, as well as vertically, are due to the revolving or pitchlike motion of the arytenoid along the minor axis of the cricoid's elliptically shaped facet. The medial and lateral movements are due to the orientation of the arytenoid which in turn is determined by the forward, lateral, and inferior inclination of the cricoid-arytenoid facet. During adduction it is the outward angulation of the vocal process from the body of the arytenoid that allows the entire length of the vocal proceses to approximate one another and to have this meeting occur at the proper vertical height.