• 대한치과보철학회지
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• 제37권1호
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• pp.71-92
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• 1999

This study is to analyze the stress and displacement on the jaws during the bilateral and unilateral clenching task on three dimensional finite element model of the dentated skull. For this study, the computed tomography(G.E.8800 Quick, USA) was used to scan the total length of human skull in the frontal plane at 1.9mm intervals. The CAD data were extracted from the tomograms through digitizer(Summa Sketch III, USA) and then reconstructed by means of the spline method in the CAD program. In this project, a commercial software I-DEAS(Master Series ver-sion 3.0, SDRC Inc, USA) was used for three-dimensional stress analysis on the finite element model. which consists of articular disc, maxilla, mandible, teeth, periodontal ligament and cranium. The results are as follows. ; 1. During the bilateral clenching, each major muscle forces caused high stresses on various areas of skull: masseter muscle on articular disc and teeth ; temporal muscle on mandible and periodontal ligament ; medial pterygoid muscle on the temporomandibular joint. During the unilateral clenching, masseter muscle induced the maximum stress ; medial pterygoid muscle the minimum stress. 2. During the bilateral clenching, higher compressive stresses on articular disc were generated by the masseter muscle and higher deformation occurred on the most front outer sites. And during the unilateral clenching, temporal muscle and medial pterygoid muscle exerted their forces to twist temporomandibular joint area of the balancing side and induced a higher compressive stresses on the front outer sites of articular disc. 3. During the bilateral clenching, the masseter muscle bended the mandible outwardly, and then caused tensile stresses on the lingual surface of mandibular symphysis. And the medial pterygoid muscle caused tensile stresses on the labial surface of mandibular symphysis. 4. When each muscles were simultaneously applied on jaws, a high stress and displacement took place on mandible rather than on the maxilla. Also, a high stress and displacement took place during the unilateral clenching rather than during the bilateral clenching.

• 대한전기학회논문지
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• 제38권7호
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• pp.524-538
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• 1989

최근에 들어 마이크로 컴퓨터를 비롯하여 사무 자동화 및 가정 자동화와 관련한 전자기기에 쓰이는 1KVA이하의 소용량 UPS의 수요가 급격히 증가하고 있다. 이와같은 UPS의 응용에서는 UPS의 소형화와 가격 절감이 가장 요구된다. 본 논문에서는 새로운 방식의 직렬 공진형 인버어터와 그의 제어 방법을 제안하였다. 제안한 인버어터는 영전류 스윗칭 방식의 공진형 컨버어터와 고주파 절연 변압기 및 영전류 스윗칭 방식의 싸이클로 콘버어터로 구성되었다. 공진 전류의 평균 크기를 정현적으로 변화시키고 싸이클로 콘버어터를 이용하여 저주파 출력 전압을 발생시킨다. 제안한 인버어터에서는 양방향 전력 전달이 가능하고 절연 변압기의 크기를 대폭 줄이고 가격도 줄일 수 있다. 제안한 제어방법을 simulation과 실험을 통하여 확인하였다.

• Archives of Plastic Surgery
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• 제48권3호
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• pp.254-260
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• 2021

Background Myelomeningocele is a frequently seen condition at tertiary care hospitals. Its treatment involves a variety of plastic reconstructive techniques. Herein, we present a series of myelomeningocele patients treated using keystone flaps. Methods We gathered information regarding soft tissue reconstruction and the use of bilateral keystone flaps to treat myelomeningocele patients. We obtained data from clinical records and recorded the demographic characteristics of mothers and children with the condition. The size, level of defect, and complications detected during the follow-up were analyzed. Results A series of seven patients who underwent bilateral keystone flaps for myelomeningocele closure was analyzed. There were no cases of midline or major dehiscence, flap loss, necrosis, surgical site infections, or cerebrospinal fluid leakage. No revision procedures were performed. Minor complications included one case with minimal seroma and three cases with areas of peripheral dehiscence that healed easily using conventional measures. Conclusions The use of keystone flaps is an adequate option for closure of dorsal midline soft tissue defects related to myelomeningocele. This technique offers predictable results with an acceptable spectrum of complications. Robust blood flow can be predicted based upon anatomical knowledge.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권4호
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• pp.353-360
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• 2009

양측 구순열의 코-입술 동시 수술의 원칙이 확립되었고 기법은 계속 진화하고 있다. 이에 따라 예전에 전형적으로 보이던 양측 구순열비의 오점들이 더 이상 명확히 보이지 않게 되고 있다. 외과의사들은 양측 구순열비 교정에 대한 원칙을 숙지하고 술전 악정형치료를 효과적으로 유도하고 성장이라는 4차원적 변화를 예견하는 3차원적 설계와 코-입술 동시 수술의 기법을 채득하여 환자를 치료하여야 한다. 또한 수술후 정기적인 관찰과 평가는 외과의사의 의무가 되어야 하고 문제가 분명해 질 때는 적절히 수정하여야 한다. 이번에 소개한 Mulliken의 치료법은 단순히 기법만을 중시하는 것이 아니라 원칙과 의무, 성장을 고려하는 4차원적 치료이다. 저자들은 이 치료법이 환자들과 외과의사들에게 많은 도움이 되기를 바란다.

• 대한두개안면성형외과학회지
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• 제19권2호
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• pp.131-134
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• 2018

Treacher Collins syndrome is a congenital disorder that is characterized with a wide range of cranio-facial deformities. Zygomatic hypoplasia or aplasia is one of the key features, and surgical reconstruction of the consequent depression on the zygomatic area is deemed necessary by many patients. Various surgical options are available-injectables, alloplastic materials, autologous grafting, and autogenous tissue transfer. It depends on each patient which technique to use. Here, we present a clinical case, in which bilateral free groin flaps were adopted in attempt to resolve the remnant aesthetic deformity associated with zygomatic depression, despite a series of previous surgical efforts, in a 25-year-old Treacher Collins syndrome male patient.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.519-519
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• 2000

Since the dynamics of the slave manipulator with high reduction ratio joints is likely to be much slower than that of the master manipulator, the control input the slave manipulator is so frequently saturated. This paper proposes a bilateral teleoperation control scheme for 2-DOF manipulators with high reduction ratio joints, which can effectively compensate the control input saturation. In the proposed scheme, the controllers of the slave manipulator are designed with an anti-windup feature and forces caused by the saturation are reflected to the operator holding the operating handle of the master manipulator. When the control input of the slave manipulator is saturated, the master manipulator moves slowly file to tile reflected forces. In this way, the position tracking performance of the slave manipulator with high reduction ratio joints can be enhanced regardless of saturation. The proposed scheme is shown to give excellent position tracking performance through a series of experiments.

• 수산해양교육연구
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• 제23권4호
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• pp.596-606
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• 2011

This article analyzed the process of concluding the Korea-Russia IUU Fishing Prevention Agreement as a model case for distant water fisheries governance. The research studied co-operations for fisheries between Korea and Russia, the current status of live crabs landed in Korea through IUU fishing and Russia's political position on the IUU issue. Also this article reviewed a series of processes executed to achieve the bilateral agreement to prevent IUU fishing, including researches, intergovernmental negotiations, institutional improvements, public hearings and presentations. There were many things closely linked together such as international FAO-IUU prevention efforts, Russia's IUU fishing issue, Korean importers of Russian live crabs, their local governments and Korean snow-crab gill-net fishermen. These issues were resolved through reasonable reconciliations. This article wants to contribute to be used as a reference for other similar IUU fisheries cases.

• 국제물리치료학회지
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• 제10권2호
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• pp.1763-1767
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• 2019

Background: Although previous researches have developed interventions for neck problems, headache, and temporomandibular disorder in patients with forward head posture (FHP), changes in masticatory muscle tone or stiffness as FHP worsening have not been investigated. Objective: To examine changes in masticatory muscle tone and stiffness through craniovertebral angle (CVA). Design: Cross sectional study Methods: The subjects were 21 healthy males with normal head posture. Three CVA were established for posture measurement in which the bilateral anterior temporal and masseter muscles were measured during the subjects maintained a series of postures. Results: The Right masseter muscle significantly increased in stiffness with advancing FHP (p < 0.05). No significant changes were observed in the muscle tone or stiffness of any other masticatory muscles, and no significant differences were found in bilateral masticatory muscle tone or stiffness in each measurement posture. Conclusions: This study suggests that the increased stiffness of the right masseter muscle as the FHP worsened requires consideration in physical therapy assessment and intervention.

• Investigative Magnetic Resonance Imaging
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• 제14권1호
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• pp.74-77
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• 2010

과립세포육종은 골수성 백혈병의 발현 형태의 하나로써, 과립세포들의 원시 전구체가 골수가 아닌 연조직에 침착하여 생긴 고형 종괴를 지칭한다. 저자들은 다른 전신 증상 없이 양쪽 안구의 돌출을 주소로 내원하여 광범위한 양쪽 안와-부비동 과립세포육종으로 진단된 22개월 남아의 CT 및 MR 소견을 보고한다. 종괴는 양측 안와 외하벽을 침범하여 양쪽 안구를 돌출시켰으며, 부비동, 상악골, 측두골, 광대뼈, 나비뼈, 벌집뼈, 입천장뼈를 포함한 거의 모든 머리뼈바닥의 골수에 침윤하고 주변에 연부 조직 종괴를 형성하였고, 해면정맥동의 아래 1/2을 침범하고 측두골 안쪽의 경질막이 비후된 소견을 동반하였다. 환아는 골수를 이용한 염색체 검사를 통해 8번과 21번 염색체의 상호전좌 t(8;21) (q22;q22)를 동반한 급성 골수성 백혈병으로 진단되었다.

• 융합정보논문지
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• 제8권2호
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• pp.83-90
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• 2018

양방향 통신 장치를 설계 및 개발하기 위한 조건을 구하기 위해 $36^{\circ}$ $LiTaO_3$기판 위에 전극을 형성시켰으며, 전극재료로는 Al-Cu(W 30%)를 이용하였다. 이 방법으로 3가지 서로 다른 샘플 전극을 제작했으며, 주파수 특성, 리플특성 및 대역범위가 유사한 두 전극을 선택 후, 직렬로 연결하여 양방향 통신 장치를 만들었다. 직렬 연결한 양방향 장치 특성은 다른 샘플 전극보다 좋은 결과를 얻었으며, 주파수는 대략 190.3MHz로 측정되었으며, 반사기와 전극 폭을 각각 $1{\lambda}/4$, $1{\lambda}/12$로 하였다. 이 결과들을 바탕으로 향후. 다중 채널을 이용한 통신 소자 개발은 물론 듀플렉스 필터 제작에도 도움을 줄 것을 희망한다.