• 한국구조물진단유지관리공학회 논문집
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• 제9권3호
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• pp.139-150
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• 2005

유한요소법을 이용하여 기둥단면이 직선형태로 변화하는 3경간 단층 골조의 두 고유치 (탄성임계하중과 횡방향 기본진동수)를 산정하였다. 수치해석에서 고려한 변수는 기둥의 taper 비 ($={\alpha}$), 경간대 층고비 ($={\beta}$), 보와 기둥의 단면2차 모멘트 비(=Y)이다. 또한 주각의 지지상태와 주두의 수평동(side-sway)유무가 고유치에 미치는 영향도 고려하였다. 하나의 연속함수로부터 고유치의 변화 추정이 가능한 대수 함수식을 제안하였다. 대수함수식의 변수는 수치해석에서의 변수 즉 ${\alpha}$, ${\beta}$ 및 Y 이다. 골조에 작용하는 축방향력의 크기를 점차 증가시켜 가면서 여기에 대응하는 진동수의 감소현상을 검토하였다.

• The Journal of Advanced Prosthodontics
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• 제12권4호
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• pp.233-238
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• 2020

PURPOSE. This study aims to compare the marginal fitness of two types of implant-supported fixed dental prosthesis, i.e., cementless fixation (CL.F) system and cement-retained type. MATERIALS AND METHODS. In each group, ten specimens were assessed. Each specimen comprised implant lab analog, titanium abutment fabricated with a 2-degree tapered axial wall, and zirconia crown. The crown of the CL.F system was retained by frictional force between abutment and relined composite resin. In the cement-retained type, zinc oxide eugenol cement was used to set crown and abutment. All specimens were sterilized with ethylene oxide, immersed in Prevotella intermedia culture in a 50 mL tube, and incubated with rotation. After 48 h, the specimens were washed thoroughly before separating the crown and abutment. The bacteria that penetrated into the crown-abutment interface were collected by washing with 500 µL of sterile saline. The bacterial cell number was quantified using the agar plate count technique. The BacTiter-Glo Microbial Cell Viability Assay Kit was used to measure bacterial adenosine triphosphate (ATP)-bioluminescence, which reflects the bacterial viability. The t-test was performed, and the significance level was set at 5%. RESULTS. The number of penetrating bacterial cells assessed by colony-forming units was approximately 33% lower in the CL.F system than in the cement-retained type (P<.05). ATP-bioluminescence was approximately 41% lower in the CL.F system than in the cement-retained type (P<.05). CONCLUSION. The CL.F system is more resistant to bacterial penetration into the abutment-crown interface than the cement-retained type, thereby indicating a precise marginal fit.

• Tuberculosis and Respiratory Diseases
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• 제46권1호
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• pp.89-95
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• 1999

저자들은 40세 남자환자에서 고열과 호흡곤란, 기침을 주소로 내원하여 개흉 폐생검상 폐쇄성 세기관지염 기질화 폐렴 진단 후 스테로이드 치료로 호전을 보이다가 임상증상의 재발과 함께 다발성근염을 보인 후 재차 스테로이드 치료에 반응을 보인 1예를 경험하였기에 이를 보고하는 바이다.

• 한국전자파학회논문지
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• 제18권3호
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• pp.305-314
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• 2007

본 논문에서는 단일 평면 구조를 가지는 CPW 급전 부채꼴형 UWB 안테나를 제안하였다. 방사 소자와 접지면이 마주 하는 부분은 지수 함수적으로 테이퍼 된 슬롯 형태를 이루도록 설계되었으며, 사각형 보우타이 구조 다이폴 안테나를 변형하여 다중 공진 모드를 형성하도록 함으로써 임피던스 대역폭을 확장시켜 $3.1\sim10.6GHz$ 에서 2 이하의 VSWR을 만족하는 특성을 구현하였다. 측정 결과 UWB 시스템 전 대역에서 -10 dB 이하의 반사손실을 만족하며, XZ 평면(Theta, $Phi=90^{\circ}$)에서 $40.1\sim89.9^{\circ}$의 반전력 빔 폭과 전 대역에서 $0.9\sim3.1dB$의 최대 이득을 나타내었다. 제안된 안테나는 기판 뒷면에 접지면이 없는 CPW 급전 구조를 사용하여 제작이 용이하고, 소형화가 가능하다.

• Steel and Composite Structures
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• 제19권5호
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• pp.1115-1144
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• 2015

Current climate conditions along with advances in technology make further design and verification methods for structural strength and reliability of wind turbine towers imperative. Along with the growing interest for "green" energy, the wind energy sector has been developed tremendously the past decades. To this end, the improvement of wind turbine towers in terms of structural detailing and performance result in more efficient, durable and robust structures that facilitate their wider application, thus leading to energy harvesting increase. The wind tower industry is set to expand to greater heights than before and tapered steel towers with a circular cross-section are widely used as more capable of carrying heavier loads. The present study focuses on the improvement of the structural response of steel wind turbine towers, by means of internal stiffening. A thorough investigation of the contribution of stiffening rings to the overall structural behavior of the tower is being carried out. These stiffening rings are placed along the tower height to reduce local buckling phenomena, thus increasing the buckling strength of steel wind energy towers and leading the structure to a behavior closer to the one provided by the beam theory. Additionally to ring stiffeners, vertical stiffening schemes are studied to eliminate the presence of short wavelength buckles due to bending. For the purposes of this research, finite element analysis is applied in order to describe and predict in an accurate way the structural response of a model tower stiffened by internal stiffeners. Moreover, a parametric study is being performed in order to investigate the effect of the stiffeners' number to the functionality of the aforementioned stiffening systems and the improved structural behavior of the overall wind converter.

• 한국임상수의학회지
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• 제27권4호
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• pp.462-467
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• 2010

A Maltese (5-years old, castrated male) and a Yorkshire Terrier (8-years old, intact female) were referred to Seoul National University Hospital for Animals with ataxia, circling, depression and anorexia. It was suspected to meningoencephalitis of unknown etiology (MUE) based on neurological signs, magnetic resonance imaging findings, cerebrospinal fluid analysis and canine distemper virus antigen test. Immunosuppressive dose of corticosteroid was initially chosen to treat in two dogs. However, the clinical signs were relapsed and side effects had arisen including polyuria, polydipsia, calcinosis cutis, liver enzyme elevation, weight gain and abdominal distension. Combination therapy of cytosine arabinoside (CA) and prednisolone (PDS) was tried. With this combination, the clinical signs were resolved and the side effects were alleviated. The dose of PDS was tapered to 0.5 mg/kg q48h in one case and the PDS was discontinued in the other case. These cases suggested that combined CA and PDS therapy may be significantly useful for the treatment of MUE uncontrolled by PDS alone.

• Clinical and Experimental Pediatrics
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• 제53권3호
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• pp.437-441
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• 2010

독성표피괴사용해(TEN)와 스티븐-존슨 증후군(SJS)은 약물이나 감염에 의해 발생하는 피부점막을 침범하는 드물지만 치명적인 질병이다. 스테로이드는 TEN의 치료에 많이 이용되어왔지만, 아직까지도 논쟁중이다. 스테로이드에 의한 정신과적 영향은 두통, 불면증, 우울증, 심리질환 등이 있다. 스테로이드에 의한 정신질환에서 치료는 스테로이드의 감량 또는 중단이고, 항정신성 약물을 투여한다. 신증후군으로 진단된 11세 남아에서 스테로이드 치료 후 관해상태에서 유지치료를 시행하고 있던 중에 TEN이 발생하였다. 저자들은 이 환아에서 치료목적으로 투여한 고용량 스테로이드 정맥주사로 인해 정신질환이 동반되었고, 이후 스테로이드 감량과 항정신성 약물과 면역글로불린으로 증상이 호전되는 것을 경험하여 이를 보고하는 바이다.

• 대한환경공학회지
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• 제22권4호
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• pp.723-731
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• 2000

유해유기화합물질 처리시 처리효율을 증대시키기 위하여, 본 연구에서는 GAC를 이용한 RSTA에서 phenol과 4-nitrophenol 의 경쟁흡착을 연구하였다. 이성분계 흡착등온시 phenol은 Freundlich 흡착동온식 적용이 불가능하였다. 그리고 활성탄 주입량이 적어짐에 따라 또 흡착질의 농도가 증가함에 따라 두 성분간의 경쟁흡착은 심화되었다. RSTA를 이용한 연속식 실힘에서는 유입유량이 감소할수록 두 성분간의 경쟁흡착성향은 증가하는 것으로 나타났다. 수축 각 변화에 따른 경쟁흡착실험에서는 수축각이 커질수록 파과시간이 증가하였으며, 활성탄 충전층 수를 변화시킨 실험에서는 충전층 수를 증가시킴에 따라 각 성분의 흡착효율 및 phenol에 대한 4-nitrophenol 경쟁흡착능은 증가하였다. RSTA에서의 이러한 성능 증대는 유체의 정제와 분리에 적용할 수 있을 것이다.

• Restorative Dentistry and Endodontics
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• 제24권4호
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• pp.633-638
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• 1999

The purpose of our study is to evaluate the ability of nickel-titanium(NiTi) files in maintaining the original curvature of a curved root canal during canal preparation. Curved canals on translucent resin blocks were prepared with Profiles and stainless steel files and they were placed at the platform which can reproduce the same position. The unprepared and prepared canal forms were accurately compared by double exposure technique of photography. The results were as follows : 1 NiTi files made a canal comparatively taper, but stainless steel files didn't make a canal taper, wicest at midportion and comparatively wide at a apical portion. 2. Canals preparations with no. 25 Profile.06 up to the working length were most excellent in taperness and in maintaining the original curvature. Canals prepared with no 30 Profile.06 up to the working length made a little outer transportation at a apical portion, but not severe. 3. Canal preparations with Profile GT were excellent in taperness and in maintaining the original curvature, but made more enlargement toward the inner side at the starting portion of the curvature. 4. Canal preparations with stainless steel files were not tapered and provided the largest transportation.

• 복식문화연구
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• 제27권6호
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• pp.632-644
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• 2019

This study presents an efficient clothes-sizing system for those experiencing obesity in old age with the aim of revitalizing the clothing industry for older obese people. The study targets 249 obese men aged 60 to 85 who satisfy a Rohrer index score of 1.6 or higher and a BMI (body mass index) of 25 or higher. Elderly obese males showed more obesity in the body based on the waist. In particular, those in their 60s were the most obese, and after reaching their 70s, characteristics of old age in which the stature was reduced and the limbs were tapered were shown. The clothes-sizing system was set to 5cm in stature, 5cm and 3cm in chest girth, 2cm in waist girth (omphalion), and 2cm in hip girth according to the KS standards. Through the two-way distribution of each section, the name of the section with a high distribution was given. Casual tops were selected from eight sizes, ranging from 155 to 170cm in stature and 95 to 105cm in chest girth. Suit top sizes were selected from eight sizes, ranging from 160 to 170cm in stature and 94 to 103cm in chest girth. Bottoms suggested 10 sizes distributed between 90 and 100cm in waist girth (omphalion) and 92 and 98cm in hip girth. According to the KS standards, the detailed size was divided into the basic part and the reference part.