• 대한정형외과스포츠의학회지
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• 제8권1호
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• pp.39-45
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• 2009

목적: 중 고교 태권도 선수의 경기 중 발생한 골절 및 탈구의 발생 양상과 원인을 조사하여 그 예방법을 알아보고자 하였다. 대상 및 방법: 2005년부터 2007년 사이에 매년 열린 전국 중 고교 태권도 대회에서 발생한 골절 및 탈구 50례를 대상으로 조사하였다. 각 손상의 양상과 원인을 분석하고 32례에서 1년 후 설문조사로 추시 조사하였으며 적절한 치료와 예방을 위한 방법을 연구하였다. 결과: 족부 골절 26례(52%), 수부 골절15례(30%), 전완부 골절 9례(18%)가 발생하였다. 32례의 1년 후 설문 조사에서 치료만족이 9례(28%), 보통이 15례(47%), 불만족이 8례(25%)였으며 불만족의 원인으로 충분한 휴식 부족(7례), 과도한 훈련(5례), 무리한 경기 출전(6례) 등이 있었고, 21례(67%)에서 부상에서 완전 회복되기 전에 훈련에 복귀하였다. 결론: 중 고교 태권도 선수에서 발생하는 골절 및 탈구의 원인은 상, 하지의 타박 손상과 족부 무지가 지면에 접질리며 발생하는 고속 과굴곡 손상이었으며 이의 예방과 치료를 위해 보다 안전한 보호 장구의 개발과 경기장 시설 개선, 그리고 충분한 휴식과 교육이 필요할 것으로 사료된다.

• Investigative Magnetic Resonance Imaging
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• 제17권1호
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• pp.26-32
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• 2013

목적: 견관절 전방탈구 후 Bankart 병변이 있었던 환자의 자기공명관절조영술 (MRA)에서 Hill-Sachs (HS) 병변의 유무와 정도를 평가하고, 이를 관절경에서 보인 Bankart 병변의 크기와 탈구 빈도와 비교하고자 하였다. 대상과 방법: 견관절 전방탈구 후 발생한 Bankart 병변의 관절경 수술을 시행 받은 86명의 MRA를 분석하였다. MRA에서 HS 병변의 가장 큰 표면길이와, 관절경에서 보인 Bankart 병변의 크기를 측정하였다. HS 병변 길이와 Bankart 병변 크기, 탈구 빈도 사이의 상관성을 분석하였다. 결과: HS 병변은 78명에서 관찰되었다. HS 병변의 가장 긴 표면길이는 평균 18.8 mm (9.3 - 29.6 mm) 였고, Bankart 병변은 평균 4.25시계구간 크기 (1-6시계구간 크기) 였다. 3명은 단일탈구, 75명은 재발탈구였다. HS 병변의 크기는 Bankart 병변의 크기와 유의한 양의 상관관계를 보였고 (p = 0.001, r = 0.37), 탈구 빈도와는 관련성이 없었다. 결론: HS 병변은 Bankart 병변이 있는 환자에서 흔하게 발견되었다. HS 병변과 Bankart 병변의 크기와 유의한 양의 상관관계를 보였다.

• Applied Microscopy
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• 제44권2호
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• pp.74-78
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• 2014

Dislocation density and distribution in epitaxial GaAs layer on Si are evaluated quantitatively and effectively using image processing of transmission electron microscopy image. In order to evaluate dislocation density and distribution, three methods are introduced based on line-intercept, line-length measurement and our coding with line-scanning method. Our coding method based on line-scanning is used to detect the dislocations line-by-line effectively by sweeping a thin line with the width of one pixel. The proposed method has advances in the evaluation of dislocation density and distribution. Dislocations can be detected automatically and continuously by a sweeping line in the code. Variation of dislocation density in epitaxial GaAs films can be precisely analyzed along the growth direction on the film.

• Clinics in Shoulder and Elbow
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• 제17권4호
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• pp.205-208
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• 2014

Sternoclavicular joint posterior dislocations are considered a very uncommon, and type of injury where if esophagus or airway injury occurs behind the clavicle, it poses a high risk to the patient. In addition, if epiphyseal fracture occurs as a result of the sternoclavicular joint posterior dislocation, surgical treatment is often required. However, in the absence of a complete ossification of the clavicle, it is difficult to differentiate between a simple dislocation and epiphyseal fracture-dislocation solely based on simple radiographs or computed tomography scans. In this case report, the authors present a case in which a sternoclavicular joint posterior dislocation was diagnosed in a 14-year-old male athlete. The case report discusses how the posterior dislocation without epiphyseal fracture was diagnosed using an ultrasound and subsequently treated with successful outcomes using manual reduction. The case report presents our findings along with discussion that includes a literature review of relevant research.

• Journal of Trauma and Injury
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• 제31권1호
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• pp.43-50
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• 2018

Traumatic hip joint dislocations account for 2-5% of total joint dislocations. Bilateral asymmetric hip joint dislocation with anteriorly and posteriorly dislocation is an even more rare case because it was according to G. Loupasis reported in 11 cases only since 1879. We want to report 2 cases of bilateral asymmetric hip joint dislocation with unilateral acatabulum fracture which happened in our hospital. Bilateral asymmetric dislocation of hip joint accompanied by unilateral fracture of acetabulum is a very rare case so statistical verification cannot be done. However, close examinations are required at early treatment and follow-up because the patterns of dislocation and fracture of hip joint are variable and an orthopedic emergent condition and several complications may occur at both hip joints.

• 한국진공학회지
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• 제6권S1호
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• pp.80-88
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• 1997

The attempt to enhance the strength of materials has been an important subject for materials engineering and scientists. The strength of materials is termed as the ability to support high load without excessive deformation and without breaking catastrophically. The control of dislocation densities and barriers to the movement of dislocations have been considered to be the important methods for the strengthening materials. One of the approaches is mechanical blocking of dislocations by alternately depositing material layers. The typical structure of materials is multilayered and laminated composites. The thickness of each layer is typically in the range of nanometer. Ton avoid confusion with other terminology they may be defined as microlaminate composite materials. The manufacturing process of multilayered laminate structure will be introduced. And the current theoretical theories will be reviewed in view of strengthening of microlaminte composite materials.

• Interaction and multiscale mechanics
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• 제1권4호
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• pp.437-448
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• 2008

This paper examined the stability of high-dense dislocation substructures (HDDSs) associated with martensite laths in High Cr steels supposed to be used for FBR, based on a series of dislocation dynamics (DD) simulations. The DD simulations considered interactions of dislocations with impurity atoms and precipitates which substantially stabilize the structure. For simulating the dissociation processes, a point defect model is developed and implemented into a discrete DD code. Wall structure composed of high dense dislocations with and without small precipitates were artificially constructed in a simulation cell, and the stability/instability conditions of the walls were systematically investigated in the light of experimentally observed coarsening behavior of the precipitates, i.e., stress dependency of the coarsening rate and the effect of external stress. The effect of stress-dependent coarsening of the precipitates together with application of external stress on the subsequent behavior of initially stabilized dislocation structures was examined.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.347-352
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• 1996

Studies on tile microstructural and compositional changes in sensitized Ni base Alloy 600 by laser surface melting have been carried out using TEM equipped with EDXA. The microstructure of the laser melted zone was mainly consisted of fine cells, and along the cell and grain boundaries, Cr enrichment due to its segregation was observed. Cr carbides having formed along the grain bundaries during the sensitization treatment have been completely dissloved. The cell walls were decorated with dislocations and the very tiny precipitates, found to be Ti(CN) type, were distributed randomly along the cell walls with tangled dislocations around them.

• 한국세라믹학회지
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• 제31권2호
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• pp.147-154
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• 1994

The imperfections of LiTaO3 crystals grown from the Pt-Rh and the Ir crucible were investigated with X-ray diffraction, optical and electron microscope. The growth direction was <100>h and the plane parallel to the plane connecting two main growth ridges was (012)h which would be the main cleavage plane. The dislocation density in the specimen cut parallel to (012)h plane increased with polishing time and the inverted ferroelectric microdomains were induced based on this dislocations. Such imperfections as 180$^{\circ}$ domains, microcracks, dislocations and stacking faults. could be found in the LiTaO3 crytals. The crystal contaminated with lots of Rh form Pt-Rh crucible during the crystal growing under air atmosphere contained more imperfections. The main cleavage plane and subgrain boundary parallel to its growing axis might be the main source of reducing the mechnical strength during the wafering process.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권5호
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• pp.238-241
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• 2013

Lateral and superior-lateral dislocations of the intact condyle are a rare complication, following traumatic insult to the mandible. We report an unusual case of a 54-year-old male patient who experienced both types of dislocations of the intact condyles with symphysis fracture following a road-traffic accident. Under general anesthesia, conventional manipulation was unsuccessful in relocating the condyles into the glenoid fossa. After applying a percutaneous traction force, using a bone traction hook placed at the sigmoid notch, the displaced intact mandibular condyles were repositioned, and the symphyseal fracture was finally reduced and fixed. The mouth opening was within normal limits, and favorable occlusion was confirmed one month postoperatively. To our knowledge, this is the first case of dislocation of both intact condyles--associated with symphysis fracture--being reduced with bone traction hook.