• Journal of the Korea Concrete Institute
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• v.14 no.4
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• pp.578-588
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• 2002

An experimental study was conducted to investigate the effectiveness of transverse reinforcement in reinforced concrete tied columns subjected to monotonically increasing axial compression. Eighteen large-scale columns(260$\times$260$\times$1200 mm) were tested. Effects of main variables such as the concrete compressive strength, the tie configuration, the transverse reinforcement ratio, the tie spacing, and the spatting of the concrete cover were considered. High-strength concrete columns under concentric axial loads show extremely brittle behavior unless the columns are confined with transverse reinforcement that can provide sufficiently high lateral confinement pressure There is a consistent decrease in deformability of column specimen with increasing concrete strength. Test results were compared with the previous confinement model such as modified Kent-Park, Sheikh-Uzumeri, Mander, and Saatcioglu-Razvi model. The comparison indicates that many previous models for confined concrete overestimate or underestimate the ductility of confined concrete.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.17-17
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• 2019

IPCC (Intergovernmental Panel on Climate Change) 기후변화 전망보고서에 따르면 RCP 4.5 시나리오 기준, 21세기 전 지구 평균기온은 $2.5^{\circ}C$ 상승(한반도 $+3.0^{\circ}C$)하며, 전 지구 평균강수량은 4.1% 증가(한반도 +16.0%)할 것이라 전망하고 있다(기상청, 2012). 최근 기후변화와 기상이변에 따른 도심지 폭우특성이 변화하고 있음을 많은 연구결과에서 말해주고 있으며, 그 발생 빈도와 강도가 점차 증가하고 있는 추세이다. 특히, 서울시의 경우 인구와 재산이 밀집해 있어 폭우 발생에 의한 시민의 인명과 재산 피해 우려가 크다. 따라서 본 연구에서는 서울시를 대상으로 근미래(~2050년) 기후변화 하에서의 재현기간에 따른 확률강우량 변화 특성을 분석하여 비교 평가한 후 설계 강우량 산정에 활용하고자 하였다. 관측자료 기반 강수량의 변동 특성 분석과 Non-stationary GEV방법을 이용한 비정상성 빈도해석을 수행하였으며, 근미래 폭우특성 변화분석을 위하여 CMIP5 (Coupled Model Intercomparison Project 5)에 참여한 GCMs(General Circulation Models)을 활용한 강우빈도해석을 수행하였다. Mann-Kendall Test와 Quantile Regression을 통한 서울지점 여름철 강수량(June to September)과 기준강수량 초과 강수(30, 50, 80, 100mm/hr), 연간 10th 최대 강수량(Annual Top 10th Precipitation) 등을 분석한 결과 최근 증가 경향이 뚜렷하게 나타났으며, 비정상성 빈도해석에 의한 확률강우량 분석의 가능성과 신뢰성을 확인하였다. 또한 19-GCMs을 통하여 모의된 일(Daily) 단위 강수량자료를 비모수통계적 상세화(Nonparametric Temporal Downscaling) 기법을 적용하여 시간(Hourly) 강우로 다운스케일링하였으며, 서울시 미래 확률강우량에 대한 IDF 곡선(Intensity-Duration-Frequency Curve)을 작성하여 비교?분석한 결과 지속시간 1시간 강우에 대하여 재현기간 30년, 100년 조건에서 확률강우량이 약 4%~11% 수준에서 증가하고 있음을 확인하였다. 본 연구의 결과는 도심지 수공구조물의 설계빈도 영향을 진단하고, 근미래 발생가능한 확률강우량 변화에 따른 시간당 목표 강우량설정의 방법론을 제시하였다는데 의의가 있으며, 서울시의 방재성능목표 설정과 침수취약지역 해소를 위한 기후변화에 따른 수공구조물 설계 시 활용이 가능할 것으로 기대된다.

• Proceedings of the Korea Contents Association Conference
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• 2012.05a
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• pp.347-348
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• 2012

본 연구의 목적은 치과위생사의 근무환경, 근골격계 질환 예방교육에 대한 인식, 작업관련성 근골격계 질환과 근무특성과의 연관성에 대하여 알아보고자 하였으며, 근골격계 질환 증상 감소를 위한 관리방안을 제시하고자 한다. 전국(서울, 경기, 대구, 포항) 210명의 치과위생사를 대상으로2011년 8월 1일부터 12일까지 자기기입식 설문지 조사를 시행한 후 회수하여 응답이 불분명하거나 크게 사고를 당한 5명을 제외한 205명에 대해서 분석 하였다. 수집된 자료는 SPSS WIN 15.0 프로그램을 이용하여 분석하였다. 그 결과 근골격계질환 예방에 관한 교육을 받은 적이 없는 치위생사가 78.0%로 대부분을 차지하였으며, 근골격계 질환 예방프로그램이 필요하다고 인식하는 치과위생사가 93.2%로 대부분을 차지하였다. 신체부위별 통증빈도를 보면, 평균이 '어깨-목 사이(오른쪽)'가 3.07로 가장 높았고, 신체부위별 통증 정도를 보면, 평균이 '발목/종아리(왼쪽)'가 1.47로 가장 높게 나타났다. 신체부위별 근골격계 질환 통증경험 관련 작업능력 지장여부를 보면, 평균이 '무릎(오른쪽)'이 1.84로 가장 높게 나타났다. 손에 대한 근골격계 질환 증상으로는 오른손의 불편함 정도를 보면, 평균이 'Abductor hallucis muscle' 부분이 2.05로 가장 높았고, 왼손의 불편함 정도를 보면, 평균이 'Thumb' 부분이 1.69로 가장 높게 나타났다.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.12
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• pp.29-35
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• 2007

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.3834-3842
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• 2011

The purpose of this study is to analyze the kinematic characteristics of children with Down syndrome got congenitally joint laxity and muscle hypotonic. The subjects are boys with Down syndrome and don't have the other disabilities. We got three dimensional position data and then calculated spatiotemporal and kinematic variables during walking on treadmill used increasingly for gait analysis and training. In result, in order to overcome their gait instability due to their musculoskeletal characteristics they walked with hip, knee and ankle joints more flexed than the typical gait pattern, and on the propulsion phase they extend the lower limb joints less than the typical, result in propel the body less than. The reason is that the more is the propulsion by extending the joints, the greater is the reaction force from the ground on heel contact. This result is expected to be used to develop the training program for intensification of musculoskeletal system aim to improve the other musculoskeletal disabilities as well as Down syndrome.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.30 no.3
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• pp.93-110
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• 2019

This study surveyed 129 librarians of public libraries in the northwestern region of Seoul to identify harmful factors under the assumption that the work and environmental factors of them would burden their musculoskeletal system and influence their work satisfaction. The results of this study showed that the musculoskeletal symptoms in the shoulder, one of the general items, were more frequently observed in women than in men. Secondly, the musculoskeletal symptoms in the arms and elbows, one of the working environment characteristics, were most frequently reported when they worked more than one year and less than three years. The musculoskeletal symptoms in the waist were influenced by the operation method; the librarians of public libraries entrusted to the Office of Education or a local government showed symptoms more frequently. The musculoskeletal symptoms in the neck were affected by working hours; librarians working in the day shift showed neck symptoms more frequently than those working in the night shift. Thirdly, when the characteristics of the work environment were examined, the musculoskeletal symptoms in the hands, wrists, and fingers were highly frequent under all characteristics of the work environment, the musculoskeletal symptoms in the waist were highly frequent under all characteristics of the work environment except for work satisfaction, and the musculoskeletal symptoms in the legs and feet were highly frequent according to the proficiency, work intensity, and physical burden. Fourthly, this study evaluated the differences in musculoskeletal symptoms according to the work satisfaction of individuals. The results revealed that the occurrence frequency of musculoskeletal symptoms for all body parts decreased as work satisfaction increased. Therefore, it will be necessary for the main body of public library operation to improve the work and working environments and enhance the work satisfaction of individuals by reducing the physical burden of the librarian of public libraries through adjusting the work intensity in order for the health of the librarian of public libraries.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.638-641
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• 1998

A recurrent myoepithelioma of the lung in a 36-year-old man is reported. The neoplasm showed histologic features identical to those described in myoepitheliomas of major and minor salivary glands on the basis of Dardick's morphological classification of Myoepitheliomas. He was treated totally with surgical en-bloc resection including the chest wall. The tumor was found to be well encapsulated, and it appeared to be mainly composed of plasmacytoid cells and clear cells with occasional microcystic spaces in a solid growth form by light microscopy. Immunocytochemical, ultrastructural and flow-cytometrical studies supported myoepithelioma differentiation.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.10a
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• pp.341-342
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• 2011

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1286-1287
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• 2015

본 논문에서는 무선충전 시스템에서 공진체의 근역장 특성을 분석하였다. 지면상의 공진체는 파장에 비해 매우 작으므로 자계 다이폴로 가정하고 영상법을 적용하여 근역장 특성을 간단히 해석하였다. 이러한 결과는 무선충전 시스템의 응용분야에 따라서 각각 다른 평가환경이 필요함을 보여 주고 있다.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.3
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• pp.248-257
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• 2007

This paper presents the control system for driving myoelectric hand prosthesis according to myoelectric signal generated in the human muscle. A surface myoelectric sensor for measuring myoelectric signal is designed a skin interface and a processing circuit according to myoelectric signal output property. The control system consists of two controller for driving dual motor, torque sensor for measuring out torque of motor, slip sensor for detecting slip of torque. The experimental results proved the proposed control system.