• Journal of applied mathematics & informatics
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• 제11권1_2호
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• pp.283-290
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• 2003

Andras Bezdek proved that if a convex n-gon and n points are given, then the points and the sides of the polygon can be renumbered so that at least[${\frac{n}{3}}$] triangles spanned by the ith point and the ith side (i = 1,2,...n) are mutually non-overlapping. In this paper, we show that at least [${\frac{n}{2}}$] mutually non-overlapping triangles can be constructed. This lower bound is best possible.

• Animal cells and systems
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• 제1권4호
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• pp.571-576
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• 1997

The playas of the Southern High Plains (SHP) of Texas, USA are an important habitat for over one million wintering waterfowl. However, the recent trend toward the modification of playas for agricultural use is threatening winter habitat of waterfowl in this region. Diurnal activity budgets of wintering mallards (Anas platyrhynchos) were conducted from 1 October to 31 March, 1983-1984, and 1984-1985) at three habitat types; steep-sided pits, terraced pits, and open lakes. All seven activity patterns (feeding, locomotion, resting, comfort, courtship, alert, and agonistic) were different (P<0.05) among the three habitat types for wintering mallards on the SHP of Texas. Terraced pits supported more feeding activity (27.8%) (P<0.001) than steep-sided pits (11.2%) or open lakes (2.6%) due to their abundance of natural seeds and aquatic invertebrates. Hens (17.5%) fed more than drakes (11.7%) (P<0.05). Locomotion (32.2%) and alert (2.8%) behavior across the three habitat types showed the highest level during the early morning (6:00-9:00 AM). Paired mallards rested more (37.9%) than unpaired mallards (25.8%) (P<0.05). Agonistic activity was highest (2.4%) in terraced pits throughout the season.

• Journal of Advanced Marine Engineering and Technology
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• 제39권10호
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• pp.1017-1022
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• 2015

Specific hydrodynamic characteristic of pump-turbine during the start and load rejection process of generating mode causes anomalous increase of water pressure, along with large machine vibration, called "S" characteristic. The aim of this study is to understand and explain the hydrodynamic performance of pump-turbine at "S" characteristic region by using a model of pump-turbine system. The operation in the condition of runway and low discharge in a typical "S" characteristic curve may become unstable and complex flow appears at the passage of guide vane and impeller. Therefore, velocity and pressure distribution are investigated to give an all-sided explanation of the formation and phenomenon of this characteristic, with the assistance of velocity triangle analysis at the impeller inlet. From this study, the internal flow and pressure fluctuation at the normal, runway and low discharge points are explored, giving a deep description of hydrodynamic characteristic when the pump-turbine system operates with "S" characteristic.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.37-39
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• 1989

In this paper, the governing equation of each analyzed region of Single-sided Linear Induction Motor was induced from Maxwell's electromagnetic equation. And the linear induction motor was analyzed by finite element method. for calculating inductance, energy perturbation method was applied.

• 대한두개안면성형외과학회지
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• 제19권2호
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• pp.139-142
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• 2018

Foreign bodies impacted in the maxillofacial region are often a diagnostic challenge. They can be a source of chronic inflammatory reactions and infections leading to the formation of an orocutaneous fistula. Such orocutaneous fistulas cause significant morbidity in most patients, eventually requiring surgery. Recently, we encountered a very rare case of an orocutaneous fistula caused by multiple foreign bodies in the cheek. Precise removal of the foreign bodies was required, and a double-sided anterolateral thigh free flap was used to reconstruct the defect. Surgeons should be aware of the complications of multiple foreign bodies and should be able to diagnose these on careful clinical examination.

• Imaging Science in Dentistry
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• 제34권1호
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• pp.55-59
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• 2004

Cleidocranial dysplasia is a rare and autosomal dominent disorder characterized by aplasia or hypoplasia of the clavicles, an open fontanelle, dental abnormalities, and short stature, A 17-year-old female who presented with short stature and subsequent delay in eruption of permanent teeth is described. she showed the abnormal hypermobility of the shoulder, ocular hypertelorism and concave nasal bridge. Radiographs revealed the underdeveloped maxilla, defect of the cranium in the fontanelle region, and aplasia of the clavicles. Characteristically, panoramic view revealed near parallel-sided borders of the ascending ramus and downward curvature of the zygomatic arch with hypoplasia. The prolonged retention of deciduous teeth with delayed eruption of permanent teeth and multiple embedded supernumerary teeth were striking. Radiographic and clinical investigations revealed Cleidocranial dysplasia.

• The Korean Journal of Pain
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• 제30권1호
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• pp.59-61
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• 2017

We report a case of fluoroscopy-guided intraarticular steroid injection for sternoclavicular joint (SCJ) arthritis caused by limited cutaneous systemic sclerosis (SSc). A 50-year-old woman diagnosed with limited cutaneous SSc presented with swelling and pain in the right SCJ. MRI revealed signs of inflammation consistent with right-sided sternoclavicular joint arthritis. After the failure of oral medications, we performed fluoroscopy-guided injection in this region. She reported complete resolution of her symptoms at 4 and 12-week follow-ups. This outcome suggests that a fluoroscopy-guided SCJ injection might be a safe and successful treatment option for sternoclavicular joint arthritis.

• 대한화학회지
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• 제39권6호
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• pp.453-458
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• 1995

Pb^{2+}$을 Pseudomonas alcaligenes 5S rRNA의 구조 분석에 응용하였다. Pb^{2+}$이 5S rRNA를 절단하는 방식은 5S rRNA의 삼차구조의 조사에 이용할 수 있을 것으로 기대되는 몇 가지 특징들을 보였다. Pb^{2+}$은 안정한 나선형 줄기들에는 작용하지 않는다. 단일가닥으로된 구역들 또는 내밀린 부분들은 그들의 분자내에서의 위치에 따라 다른 민감도로 작용을 받는다. 불안정한 d 나선은 전혀 작용을 받지 않는다. 불안정한 C 줄기에서는 3'쪽의 가닥만이 작용을 받고 5'쪽의 가닥은 작용을 받지 않는다. Pb^{2+}$에 의한 절단과 Xanthomonas celebensis 5S rRNA의 구조분석의 결과들에 기초하여 우리는5S rRNA에서의 삼차상호작용에 대한 작업가설을 제안하였다.

• 한국산학기술학회논문지
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• 제11권6호
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• pp.2263-2268
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• 2010

본 논문은 SDS-TWR(Symmetric Double-Sided Two_Way Ranging)의 Ranging 오차를 보정하여 위치인식 성 능을 향상시키는 방법으로 비컨노드의 거리별 Ranging 오차의 평균 값을 이용하여 Ranging 오차를 보정하는 알고리즘($CA_d$)과, 균등거리비율의 적용으로 Ranging 오차를 보정하는 알고리즘(AEDR)이 적용된 하이브리드형 위치인식 보정 알고리즘($A_{HB}$)을 제안하고, 위치인식 실험을 통해 성능을 분석하였다. 실험결과, $A_{HB}$ 는 전체 32개의 좌표 중 28개 좌표에서 오차 개선이 이루어졌고, 설정한 3개의 오차크기 영역에서 최소한 70%이상의 오차 개선이 이루어졌음을 확인하였다. 또한 32개 좌표에서 발생한 평균 오차 2.67m를 1.19m로 55.4% 보정하였으며 특히 3m 이상의 오차크기 영역에서의 보정 성능은 90% 이상으로 매우 우수함을 확인하였다. 이와 같은 결과를 볼 때, $A_{HB}$ 는 $CA_d$와 AEDR이 각각 수행되었을 때 보다 오차 개선 비율 및 보정 성능이 더 우수함을 확인하였다.

• 마이크로전자및패키징학회지
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• 제23권3호
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• pp.63-67
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• 2016

본 논문에서는 폴리머 기반의 유연 기판 위 적층 된 다양한 필름의 굽힘 탄성계수의 간접 측정법을 소개한다. 패키징 기판의 다양한 적층 재료들의 탄성계수는 기계적으로 신뢰성 있는 전자기기 개발에 결정적이지만, 기판과 매우 견고히 접합하고 있는 적층 필름을 온전히 떼어 내어 자유지지형(free-standing) 시편을 만들기 어렵기 때문에 그 측정이 쉽지 않다. 이를 해결하기 위해 본 연구에서는 필름-기판의 복합체 시편에 대한 3점 굽힘을 진행하였고 시편 단면에 면적 변환법(area transformation rule)을 적용한 응력 해석을 수행하였다. 탄성계수를 알고 있는 기판에 대하여, 굽힘 시험으로 얻은 다층 시편의 강성으로부터 필름과 기판의 탄성계수 비를 계산하였으며, 전기 도금 구리 시편을 이용하여 양면 적층, 단면 적층의 두 가지 해석 모델이 실험 평가되었다. 또한 주요 절연체 적층 재료인 prepreg (PPG)와 dry film solder resist (DF SR)의 굽힘 탄성계수가 양면 적층 시편 형태로 측정 되었다. 결과로써 구리 110.3 GPa, PPG 22.3 GPa, DF SR 5.0 GPa이 낮은 측정 편차로 측정 됨으로써 본 측정법의 정밀도와 범용성을 검증하였다.