• 대한기계학회논문집A
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• 제27권12호
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• pp.2039-2046
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• 2003

Storage tank filled with fluid has unique dynamic characteristics compared to general structures, due to the interaction between fluid and structure. The oscillation of the fluid surface caused by external forces is called sloshing, which occurs in moving vehicles with contained liquid masses, such as trucks, railroad cars, aircrafts, and liquid missles. In this study, the evaluation method for the reduction of sloshing, the optimized size and location of wing and diaphragm baffles are suggested based on the experimental results. The experimental device can simulate the translation motion. A rectangular tank and various baffles are fabricated to study on the sloshing characteristics. The forces measured using the load cell at tank wall and those are compared with each other through the Fourier transformation for various conditions. The study of the sloshing of the rectangular tank equipped with baffles is conducted under the same conditions with non-baffled rectangular tank experiment. From the experimental results, the sloshing reduction effect by the baffles is observed. In conclusion in case of diaphragm baffles, the optimized size ratio of the width of baffle to the water height is 0.44 and the installation location has no effect to the damping of sloshing. In case of wing baffles, the optimized size ratio of the width of baffle to the length of a rectangular tank is 0.1 and the optimized location ratio of the baffle to the water height is 0.9.

• 대한관절경학회지
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• 제2권2호
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• pp.124-128
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• 1998

From Feb. 1996 to Feb. 1997. among sixty-four patients of anterior cruciate ligament(ACL) reconstruction using multi-stranded hamstring tendon and EndoButton fixation, twenty-five patients of volunteer, 15 men and 10 women, from 16 to 50 years of age(mean 27.6 years) underwent arthroscopic evaluation. Arthroscopic evaluation was routinely performed one year after surgery along with an examination of stability. The purpose of this study was to arthroscopically evaluate the morphological changes that occurred in hamstring tendon autograft one year after ACL reconstruction. Both of the tendon graft and the adjacent fibrous tissues were observed for gross appearance and physical properties with probing and response to passive anterior translation. Biopsy samples were taken from the surrounding fibrous tissue and the tendon graft. Grossly, we found a well-defined ligamentous structure with good tension tested with a probe. A common finding was that the reconstructed ligaments were embedded in a layer of the synovium, and blood vessels could be seen on the anterior surface of the ligament. The biopsy tissue was placed in formalin solution and subjected to histological preparation by hematoxylin and eosin staining method. The hamstring tendon graft appeared histologically normal under light microscopic finding. There were a few vessels located between existing collagen bundles, and the vessels had an orderly pattern. The surrounding fibrous tissue envelope was covered with synovium. We pleased with preliminary findings in our evaluation.

• 대한치과교정학회지
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• 제23권2호
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• pp.263-273
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• 1993

The purpose of this study was to analyse the center of resistance of the maxillary first molar using the 3-dimension finite element method. An extracted maxillary first molar of normal shape and average root length was selected and sectioned every 1.5mm parallel to the cementoenamel junction. Each section was traced and digitized to construct 3-D finite element model of the maxillary first molar. After a certain magnitude of counterbalancing moment(M) was applied to the tooth, a varying single force(F) of distomesial direction was applied to a certain point of th tooth until the tooth was translated. The force producing translation(Ft) was substituted to the equation ${\Delta}d=M/Ft$ to calculate the center of resistance of the maxillary first molar. And reducing the alveolar bone level 1.68mm, and 3.36mm below to the cementoenamel junction, the tooth movement was analysed to see the effect of reducing the alveolar bone level to the location of the center of resistance. The results were as follows ; 1. The center of resistance of the maxillary first molar was 3.72mm apical, 1.10mm buccal, and 0.71mm mesial to the geometric center of the horizontally sectioned surface at the cementoenamel junction. This point was 0.36mm apical, 1.20mm buccal, and 0.71mm mesial to the trifurcation point, indicating that it was not on the tooth root. 2. As the alveolar bone level was reduced, the center of resistance of the maxillary first molar was moved to the apical direction.

• 한국균학회지
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• 제44권4호
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• pp.365-370
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• 2016

본 연구에서는 잣나무, 눈측백의 침엽과 자란의 뿌리에서 식물에 공생하는 내생균을 분리하여 동정하였다. 이를 위해 specific primer인 ITS1F와 ITS4를 이용하여 internal transcribed spacer (ITS) rDNA영역과 primer LR0R과 LR 16을 이용하여 large subunit rDNA 영역을, primer Bt2a과 Bt2b를 이용하여 ${\beta}$-tubulin 영역을, 그리고 EF-1 primer를 이용하여 translation elongation factor 지역의 염기서열을 동시에 분석하였다. 연구 결과 Colletotrichum simmondsii, Fusarium sterilihyphosum, Diatrypella pulvinata, Ochroconis globalis, Sphaeria chrysosperma 등 국내 미기록 균주 5종을 분리하여 형태적, 분자생물학적 동정 결과를 서술하였다.

• 전기학회논문지
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• 제61권12호
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• pp.1828-1835
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• 2012

In this paper, a conceptual design and a detailed design of novel cylindrical magnetic levitation stage is introduced. This is came from planar-typed magnetic levitation stage. The proposed stage is composed of cylinder-typed permanent magnet array and semi-cylinder-typed 3 phase winding module. When a proper current is induced at winding module, a magnetic levitation force between the permanent magnet array and winding module is generated. The proposed stage can precisely move the cylinder to rotations and translations as well as levitations with the magnetic levitation force. This advantage is useful to make a nano patterning on the surface of cylindrical specimen by using electron beam lithography under vacuum. Two methods are used to calculate required magnetic levitation forces. The one is 2D FEM analysis, the other is mathematical modeling. This paper shown that results of two methods are similar. An assistant plate is introduced to reduce required currents of winding module for levitations in vacuum. The mathematical model of cylindrical magnetic levitation stage is used for dynamic simulation of magnetic levitations. A lead-lag compensator is used for control of the model. Simulation results shown that the detail designed model of the cylindrical magnetic levitation stage with the assistant plate can be controlled very well.

• 한국철도학회논문집
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• 제12권2호
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• pp.321-328
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• 2009

기존 터널에 근접하여 절리암반 굴착시 사면의 적절한 보강방법 및 시기는 굴착사면과 터널과의 근접도, 굴착사면 경사는 물론 절리상황에 의해 영향을 받자만 현재까지는 경험적으로 결정되고 있다. 본 연구에서는 터널에 근접하여 절리암반 지반을 굴착시 굴착단계에 따른 굴착사변에서의 하중전이 특성과 터널거동과의 상관관계를 분석하기 위하여 절리각도와 굴착사면 경사를 영향인자로 한 대형 모형시험을 실시하였다. 시험결과, 터널변형은 터널 천정부 또는 바닥부에 근접한 절리면 굴착시 가장 크게 발생을 하였으며, 사면과 터널의 안정성은 굴착사면의 경사와 관련하여 굴착단계에 따라 변화하였다. 향후 본 연구결과를 활용하여 절리암반에서의 터널과 사면의 보강방안을 도출하고자 한다.

• 한국지반공학회논문집
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• 제27권11호
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• pp.27-37
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• 2011

모래지반에서 석션파일의 최대인발저항력 산정을 위한 일련의 원심모형실험이 수행되었다. 최대인발저항력 산정을 위한 실험인자인 석션파일의 인발각과 인발작용점의 위치에 대하여 실험을 수행하였다. 인발작용점의 경우 75%에서 최대인발저항력이 관찰되었다. 모든 경사각에 대하여 전체파일 높이에서 50%에서 75%사이에 석션파일의 회전각이 변함을 알 수 있었다. 인발각이 증가함에 따라 최대 인발저항력 발생 시까지의 변위가 점점 작아짐을 알 수 있었다. 석션파일의 형상중심의 수직변위를 최대인발저항력이 작용한 시점에서 관찰한 결과 모두 지표 쪽으로 이동한 것을 알 수 있었다.

• 대한족부족관절학회지
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• 제18권4호
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• pp.178-182
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• 2014

Purpose: The purpose of this study was to evaluate the frequency of troughing and stress fracture, which are the major complications of scarf osteotomy, and to suggest methods to prevent these complications. Materials and Methods: We reviewed 243 cases of 137 patients treated with the scarf osteotomy for hallux valgus from January 2005 to December 2012. The mean follow-up period was 2.8 years. During the scarf osteotomy, a long oblique longitudinal osteotomy was performed in order to decrease the possibility of troughing and stress fracture. Radiographs of lateral view of the foot were obtained and the thicknesses of the first metatarsal base at the sagittal plane were measured and compared. Results: There was no troughing during fragment translation and screw fixation intraoperatively. Radiographs of lateral view of the foot taken preoperatively and at the last follow-up showed that the mean thickness of the first metatarsal was 22.4 mm preoperatively and 21.6 mm at the last follow-up, with a mean difference of 0.8 mm. And no stress fracture was observed. Conclusion: To prevent troughing and stress fracture, a long oblique longitudinal cut, parallel to the first metatarsal plantar surface, was performed, making both ends of the proximal segment truncated cone-shape, and securing the strong bony strut of the proximal segment. No troughing or stress fracture was experienced with scarf osteotomy.

• 한국정보통신학회논문지
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• 제9권8호
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• pp.1709-1715
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• 2005

본 논문은 3차원 웹 그래픽 라이브러리의 개발에 관한 논문이다. 본 3차원 웹 그래픽 라이브러리는 웹 응용 서비스에서 사용자에게 2차원 웹 응용 서비스 또는 기존의 3차된 점 서비스에서 시야각이 한정된 그래픽 제공의 경우 보다 다양한 동적 입체감을 제공함으로써 더욱 사용자의 흥미를 유발할 수 있는 웹 응용서비스를 개발하는데 이용 가능한 3차원 웹 그래픽 라이브러리이며 다양한 3차원 웹 객체 및 현실감 있는 드로잉 기법의 적용으로 더욱 복합적이고 동적인 3차원 웹 서비스를 제공하기 위한 3차원 웹 응용 서비스의 개발에 응용이 가능하다. 특히, 3차원 웹 게임이나 웹을 이용한 동적 광고 매체 제작에 효과적으로 이용 가능하다. 본 3-D 웹 그래픽 라이브러리는 자바 언어를 이용하여 작성되었으며 자바 가상 머신과 연동하는 웹 브라우저를 통해 웹 상에서 수행되는 응용 소프트웨어의 개발에 적용 가능하다.

• 생약학회지
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• 제42권3호
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• pp.246-252
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• 2011

Korean mistletoe Lectin (KML-C) is composed of A and B sub-chain. B chain binds to carbohydrates on cell surface and A chain hinders translation and induces an apoptosis as a RIP (ribosome inactivating protein). KML-C has very strong biological activities, it has seriously limits to use as a cancer therapy or adjuvant because of its toxicity to normal cells. This study is therefore conducted to see if B chain of KML-C might have immunological activity, especially adjuvant activities with less toxicity. We isolated B chain from KML-C using the lactose affinity chromatography, and examined their immunoadjuvant activity. The isolated B-chain did not show any cytotoxicity against tumor cell, RAW264.7, and P388D1 while KML-C had a very strong toxicity. This non-toxic effect was observed also by in-vivo study. Both humoral and cellular immunities were observed ; the antibody titer was increased when the mice were immunized with B-chain used as adjuvant like Freund's adjuvant, indicating that B chain of mistletoe lectin alone might be used for adjuvant; it also increased DTH in cellular immunity. These results suggest that B-chain of KML-C might be used for adjuvant used for the production of antibody or vaccine with less toxicity.