• 한국구조물진단유지관리공학회 논문집
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• 제23권1호
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• pp.171-178
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• 2019

본 연구는 탄소섬유시트, 아라미드섬유시트, 그리고 유리섬유시트를 혼합한 하이브리드 FRP 플레이트를 제작하였으며, 제작한 보강 플레이트를 보강한 후, 최대한의 휨 보강 효과가 발생되도록 다시 보강 플레이를 긴장시켜 RC보의 휨 보강 효과를 파악하고자 하였다. 또한, 긴장시키는 보강방법을 제시하는 동시에 무보강 실험체에 비해 보강효과가 어느 정도 되는지 실험적으로 규명하기 위해 실험적 연구를 진행하였다. 연구를 위해 총 8개의 RC 보 부재를 동일하게 제작하여 1 개의 실험체(N 실험체)를 제외한 7 개의 실험체는 보강재 종류, 단부 정착 앵커 개수, 보강재 두께 등을 주요 변수로 하여 실험을 실시하였다. 실험결과, 휨 거동을 보이는 실험체에 긴장을 가한 FRP 플레이트로 보강하면, 보강하지 않은 실험체에 비해 우수한 휨거동(초기강도, 항복시 강도 및 강성, 최대강도 등)보여 주었으며, 단부정착 앵커의 개수가 많고, 보강재의 두께(보강량)가 클수록 보강효과가 우수한 것으로 나타났으며, 긴장시킨 보강재는 단일 FRP 플레이트에 비해, 하이브리드 FRP 플레이트를 적용했을 때 보강효과가 더 우수하게 나타났다.

• 한국의상디자인학회지
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• 제15권3호
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• pp.109-118
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• 2013

Fashion icons of 21st century are not only the fashion leaders that show fashion trend but also the typical fashion signs or symbols that show visually changes in sensibility trends. The purpose of this study was to analyze the framework of 21st century fashion by the public to recognize through these changes. In this study, the background of the occurrence of various 21st century fashion icons and their characteristics were investigated and the changes of revealed features and symbolic meanings were examined compared with them of 20th century. The 24 celebrities which have been called as the bests of fashion icons since year 2000 were selected by searching the most popular search engines such as daum, yahoo and google, and 13 of them were picked as the highest in preference and awareness by surveying 50 students majoring in fashion. And then their fashion styles, backgrounds, and influence on the public fashion were studied. As a result, the 21st century fashion icons reflecting the cultural characteristics such as convergence and exaggeration and the sensitivities of fusion, collaboration, hybrid sensibility in art were powerful enough to create innovative styles destroying the era and the standard. Their styles have constantly created new looks. The exposed new individual sensitivities on media-fusion of two or more sensibility and coordination techniques without being tied to the existing anchorage system-were as influential as high fashion and leaded the imitation and reproduction by dazzling the public. As the media become more powerful, the influence of fashion icons interacted more closely with the public and has been evolved through the sensitivity of the reversal, cultural, economic, visual, or temporal fusions. To sum up, it is shown that the outstanding fashion styles suggested by the leading fashion designers have approach to the public more closely by the fashion icons.

• 대한치과교정학회지
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• 제48권5호
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• pp.304-315
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• 2018

Objective: The purpose of this study was to analyze initial displacement and stress distribution of the maxillofacial complex during dentoskeletal maxillary protraction with various appliance designs placed on the palatal region by using three-dimensional finite element analysis. Methods: Six models of maxillary protraction were developed: conventional facemask (Type A), facemask with dentoskeletal hybrid anchorage (Type B), facemask with a palatal plate (Type C), intraoral traction using a Class III palatal plate (Type D), facemask with a palatal plate combined with rapid maxillary expansion (RME; Type E), and Class III palatal plate intraoral traction with RME (Type F). In Types A, B, C, and D, maxillary protraction alone was performed, whereas in Types E and F, transverse expansion was performed simultaneously with maxillary protraction. Results: Type C displayed the greatest amount of anterior dentoskeletal displacement in the sagittal plane. Types A and B resulted in similar amounts of anterior displacement of all the maxillofacial landmarks. Type D showed little movement, but Type E with expansion and the palatal plate displayed a larger range of movement of the maxillofacial landmarks in all directions. Conclusions: The palatal plate served as an effective skeletal anchor for use with the facemask in maxillary protraction. In contrast, the intraoral use of Class III palatal plates showed minimal skeletal and dental effects in maxillary protraction. In addition, palatal expansion with the protraction force showed minimal effect on the forward movement of the maxillary complex.

• 한국항해항만학회지
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• 제34권5호
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• pp.311-317
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• 2010

하역장치가 장착된 모바일하버 선박은 새로운 해상운송시스템 개념으로, 특정 정박지에서 대형 컨테이너 선박에 계류하여 해상상태 3 이하 조건에서 신속하면서 효율적인 컨테이너 하역작업을 수행하는 것이다. 모바일하버와 관련한 주요 연구로는 고속하역시스템, 부유체 구조 설계, 안벽하역시스템 해석 및 작업크레인 설계 등의 원천기술 개발을 중심으로 수행되었다. 본 연구는 모바일하버 선박의 하역작업 중 동적안정성 확보를 위한 계류안정화시스템을 개발하고자 하는 것으로, 국내외 계류장치에 대한 현황 분석을 기초로 현재 선박에 탑재되어 있는 의장장치인 윈치시스템에 계류안정화 기능을 추가시킨 포지셔닝윈치를 개발하여 모선과의 상대운동을 최소화하는 방안에 대한 개념설계를 제안한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권2호
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• pp.129-134
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• 2001

Since NNK is one of the most abundant tobacco-specific alkaloids and a strong carcinogenic nitrosamine, it has been used for evaluating a potential of carcinogenicity in the animal models. The present study has attempted to examine the potential of carcinogenicity of NNK in human epithelial cells, from which the cell type the most of cancers including oral cancer and nasal cavity cancer are originated. The cellular model used for the study is a human keratinocyte cell system immortalized by Ad12-SV40 hybrid virus. The cellular system has successfully been used for the carcinogenicity studies because of its limitless life span, epithelial morphology and nontumorigenicity. When cells were treated with a variety of NNK concentrations, levels of saturation density and soft agar colony formation were increased in a dose-dependent fashion. Colonies of large cell aggregates were above 5 at the higher doses. The results indicate that exposure of human cells with NNK induced loss of contact inhibition and increases of anchorage independence and cellular adhesion, which are typical characteristics of the neoplatically transformed cells. When cells were exposed with 100uM NNK for 2hr, mRNA levels of IL-1 and PAI-2 were increased in a dose-dependent manner, but expression of TGF- 1 was not affected. While expression of growth regulatory factors were altered with a short-term exposure, there was no alteration of these factors in the NNK-transformed cells. However, mRNA levels of fibronectin were increased both in the short-term treatment and in the transformation. The results suggest that altered expression of extracellular matrix such as fibronectin following short-term exposure might be fixed in the genome and these altered properties be continuously transfered throughout the cell division. Western blot analysis showed a translocation of PKC- from cytosolic fraction to the particulate fraction, indicating a possible role of NNK in the signal transduction pathway. The present study provided an evidence that NNK in the smoking may be associated with epithelial origin cancer such as oral and nasal cavity cancers. In addition, this study suggested that altered expression of extracellular matrix and PKC may play an important role in the carcinogenic mechanism of NNK.