• 한국전기전자재료학회논문지
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• 제36권2호
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• pp.158-163
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• 2023

Recently, the global demands for high voltage power semiconductors are increasing across various industrial fields. The use of electric cars with high safety and convenience is becoming practical, and IGBT modules of 3.3 kV and 1.2 kA or higher are used for electric locomotives. Delicate design and advanced process technology are required, and research on the optimization of high-voltage IGBT parts is urgently needed in the industry. In this study, we attempted to design a simulation process through TCAD (technology computer-aid design) software to optimize the process conditions of the fielding process among the core unit processes for an especial high yield voltage. As well, the prior circuit technology design and a ring pattern with a large number of ring formation structures outside the wafer similar to the chip structure of other companies were constructed for 3.3 kV NPT-IGBT through a unit process demonstration experiment. The ring pattern was designed with 21 rings and the width of the ring was 6.6 ㎛. By changing the spacing between patterns from 17.4 ㎛ to 35.4 ㎛, it was possible to optimize the spacing from 19.2 ㎛ to 18.4 ㎛.

• 한국항공우주학회지
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• 제46권1호
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• pp.18-31
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• 2018

회전익 항공기는 수직이착륙, 제자리비행 특성으로 일반적으로 고정익 항공기에 비해 높은 내추락 기준이 적용된다. 최근 고효율 친환경 운송시스템에 대한 요구의 증가와 더불어 항공기 구조재료로 복합재료의 적용이 증가하는 추세이다. 그러나 외부 충격, 충돌에 취약한 복합재료의 특성으로 인해 복합재 구조의 내추락 안전성 입증에 대한 요구 또한 증가하고 있다. 본 연구는 회전익항공기 적용을 위한 복합재 내추락 하부동체 구조 개념을 도출하고 이에 대한 검증을 목적으로 수행되었다. 내추락 하부동체 구조 개념 생성을 위해 기술 실증용 헬리콥터 개념설계 및 충돌에너지 흡수 요구도 산출을 수행하였으며, 복합재 충돌에너지 흡수 구조 설계 및 성능 검증을 수행하였다. 최종적으로 복합재 내추락 하부동체구조 시제 제작 및 자유낙하시험을 수행하였다. 시험 결과 분석을 통해 탑승자 생존성 확보를 위한 내추락 안전성 기준에 부합하는 결과를 확인할 수 있었다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.327-331
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• 2018

본 연구는 대학생들의 SW 교육 핵심역량 중 컴퓨팅 사고력을 신장시키기 위해 역량 교수 학습 모델을 설계하였다. 사전에 소프트웨어 코딩 경험이 없는 학습자의 역량을 분석하고 기존의 SW 중심 교수 학습 5가지 모델 중 시연 중심 모델(DMM)과 개발 중심 모델(DDD) 그리고 CT 요소 중심 모델(DPAA) 등을 재구성하고 실생활 문제를 해결 및 컴퓨팅 사고력을 키우기 위한 Unplugged 활동과 Bebras Challenge 컴퓨팅 사고력 평가 도구 등을 면밀히 분석하여 역량 교수 학습 모델인 UDDPAAP (Unplugged-Demonstration-Decomposition-Pattern Recognition-Abstraction-Algorithm-Progrmming)을 설계하였다. Unplugged 활동 중 일부분을 대학생들 수업에 적합하게 변형하고, Bebras Challenge 컴퓨팅 사고력 평가 도구에서 제시하는 문제를 선별한 후 기존의 교수 학습 모델에 적용하였다. 연구의 효과를 검증하기 위해 코딩 경험이 없는 대학교 1학년 학생들에게 SW 교육 및 컴퓨터 정보 소양 교육 경험에 따른 컴퓨팅 사고력과 자신감 등의 사전 검사를 하고 UDDPAAP 교수 학습 모델을 적용하여 수업을 진행한 후 사후 검사를 하였다. 연구 결과 UDDPAAP 교수 학습 모델을 통해 SW 교육을 경험한 학생들의 컴퓨팅 사고력 관련 역량이 향상됨을 알 수 있었다.

• Earthquakes and Structures
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• 제3권2호
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• pp.141-168
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• 2012

The Retrofit Yield Spectrum (RYS) is a new spectrum-based device that relates seismic demand of a retrofitted structure with the fundamental design parameters of the retrofit. This is obtained from superposition of Yield Point Spectra with design charts that summarize in pertinent spectrum-compatible coordinates the attributes of a number of alternative retrofit scenarios. Therefore, once the requirements for upgrading a given structure have been determined, the RYS enable direct insight of the sensitivity of the seismic response of the upgraded structure to the preliminary design decisions made while establishing the retrofit plan. By virtue of their spectrum-based origin, RYS are derived with reference to a single mode of structural vibration; a primary objective is to control the contribution of this mode in the retrofit design so as to produce a desirable distribution of damage at the ultimate limit state by removing soft storey formations and engaging the maximum number of structural members in deformation, in response to the input motion. Calculations are performed with reference to the yield-point, where secant stiffness is proportional to the flexural strength of reinforced concrete members. Derivation and use of the Retrofit Yield Spectra (RYS) refers to the seismic demand expressed either in terms of spectral acceleration, spectral displacement or interstory drift, at yield of the first storey. A reinforced concrete building that has been tested in full scale to a sequence of simulated earthquake excitations is used in the paper as a demonstration case study to examine the effectiveness of the proposed methodology.

• 한국실내디자인학회논문집
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• 제16권2호
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• pp.295-302
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• 2007

The use of colors plays an important role in the field of space design. The selection of proper colors influences on people who use space by making the most of the psychological and physical functions of colors. Especially, the medical space is relatively more important than other indoor spaces in the selection of colors. The medical space has to be something to do with diversity and functions, and at the same time with stability and quietude, as well as the space with general convenient facilities. Color is not only related to the expression but also to the distinction of things and the existence. It also functions as a visual language. Human beings depend heavily on the function of color as a visual language. According to previous studies, human beings depend on color by 80% of the whole range of eyesight. Thus, color is an important factor in recognizing things and space. For example, in hospital, it Is very important to apply proper colors to various medical treatment spaces for the sake of patients' rest and healing. Various colors which do not consider the function of patients' rest and healing may make the space confusing against the change of space and structure. It is also important to apply colors to the change of space and structure. Another key point that I would like to make is that color has visual, direct and physical influence on the human body. For example, the color red with long wavelength serves to regulate body temperature. Research on the color scheme for hospitals should consider both physical and psychological factors. That is why the research should be carried out in depth through continuous clinical demonstration. The present research aims to outline color planning.

• 한국실내디자인학회논문집
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• 제25권5호
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• pp.16-30
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• 2016

There is an increasing interest in and efforts for safe residential environment from crimes nationwide. Many cities are making efforts to create safe residential environment by enacting ordinances and guidances on safe design for preventing crimes and implementing demonstration projects. In line with the trends of the times toward 'improvement of living conditions' through urban regeneration, the importance of the Crime Prevention Through Environmental Design(CPTED) has recently emerged in the field of residential housing regeneration. Indeed, the CPTED is included as essential factor in the recent deteriorated residential area regeneration related projects. In this respect, the purpose of this study is to provide the basic data on the methodology of CPTED to be applied to the regeneration of deteriorated residential area in the future. To this end, this study selected three representative CPTED projects in Busan - 'Deokpo-dong Hope and Stepping Stone Village,' 'Chilsan-dong CPTED Happiness Village' and 'Sujeong-dong Crime Prevention and Safe Village' as objects of this study and then investigated and analyzed project contents, application of CPTED strategy, subjects who are implementing projects, and the time when they implement projects as the framework of my analysis. The findings from this study are as follows: First, the projects that were largely based on hardware should be improved by including software in the future. Second, the current Step 2 should expand into Step 3 Maintenance in applying CPTED strategy. Third, it is necessary to encourage exchange and cooperation between unit projects and subjects who are operating related projects.

• 방사성폐기물학회지
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• 제6권3호
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• pp.233-244
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• 2008

본 연구에서는 경수로 사용후핵연료로부터 핵연료 물질(예: 차세대형 원자로의 연료)로 재사용할 수 있는 우라늄과 초우라늄원소군(TRU)을 분리, 회수하기 위한 파이로 처리공정(pyroprocess) 시설의 개념설계연구를 수행하였다. 이 시설의 목적은 공학적 실증시험을 통하여 상용 규모의 확대(scale-up) 자료를 확보하는 것과 운전 경험을 쌓을 수 있도록 하자는 것이고 그 용량은 비교적 작은 공학적 규모인 20 kg HM/batch 로 설정하였다. 처리 대상 핵연료로는 경수로의 전형적인 핵연료 형태인 3.5 % 농축우라늄, 35,000 MWd/tU 그리고 5년 냉각시킨 경수로 사용후핵연료를 선택하였다. 본 개념설계연구에서 고려한 주요 항목은 차폐셀을 포함한 파이로 처리공정 시설의 배치, 공정 운전에 대비한 시설 안전 관리, 방사선 안전, 차폐셀 내 불활성 분위기 관리, 연료 물질의 계량 관리, TRU 제품의 핵임계 관리 등이다.

• 교육시설 논문지
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• 제21권3호
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• pp.19-28
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• 2014

Student halls and their convenient facilities have been a focal point for various student activities at university campus. It has been for most of the student a place of unique memories and of attachment often associated with those good and bad school days. However, it is questionable whether these facilities are supportive and accessible for all of the students and other users including the handicapped. Therefore, based on the concept of UD(universal design) which was widely applied to U.S. institutions, this study intended to evaluate student hall facilities in U.S. and to provide an improvement direction for Korean UD application. For that purpose, four universities were selected for an in-depth analysis and 76 survey indices were utilized based on previous research. It was found that (1) design consideration without braille sign for VIP(visually impaired person) in student buildings can be differently approached with electronic devices; (2) the best demonstration of UD in student buildings can be seen in spacious flat pathway, easy access through ramp and wide entry area, necessary for people in wheel-chairs, but used by all, implying an increase of the ratio of public space; (3) one of the good UD features is an attractive physical environment rather than institutional appearance, in which they ultimately will support and completely adaptable at optimal levels by everyone; (4) consistent maintenance and management maximize the potential of UD principles and minimize physical limitations.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.21-27
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• 2008

In this study, the design of the solar heating system for district heating as well as it's operating characteristics and the performance analysis was carried out. This solar district heating system was composed of two different types of solar collector circuit, flat plate and vacuum tube solar collector, in a system. This system supply constant temperature of hot water without solar buffer tank. For this, the proportional(variable flow rate) control was used. The experimental facility for this study was used the Bundang district solar heating system which was installed in the end of 2006. The operating characteristics and behaviour of each collector circuits are investigated especially for the system design and control. The yearly solar thermal efficiency is 47.5% on the basis of aperture area and 39.8% on the basis of gross area of collector. As a result this solar heating system without solar buffer tank and with proportional controller was testified a very effective and simplified system for district heating. It varied especially depend on the weather condition like as solar radiation and ambient temperature.

• 전기학회논문지
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• 제66권10호
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• pp.1532-1539
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• 2017

The floating photovoltaic system is a new concept in the renewable energy technology. That is similar to land based photovoltaic technology except floating system. So the system needs buoyant objects, mooring, ect, besides modules and supports, and that is able to withstand in water level changes and wind strength. Therefore the floating photovoltaic system is much different from land photovoltaic system. K-water (Korea Water Resources Corporation) has been operating two floating photovoltaic system that's capacity is 100 kW and 500 kW respectively since in summer 2011 for commercial generation, and have construction project for 2,000 kW in Boryeong multipurpose Dam and other areas. Furthermore K-water was developing a tracking-type floating photovoltaic system at Daecheong multipurpose Dam and developed and installed an ocean floating photovoltaic demonstration plant at Sihwa Lake in October 2013 for R&D. In this paper, we introduce that structure of floating photovoltaic system include buoyant structure, mooring system and auxiliary device. Especially the rope which is in part of mooring should be always maintain tension under any water level. Also we explain about structure design concept to wind load in an every loading condition and a kind of structure materials and PV structure types used in water environment. Especially ocean floating PV system is affected by tidal current and typhoon. So there are considering the elements in design. Finally we compare with floating and land photovoltaic on power amount. As a result of that we verified the floating photovoltaic system is more about 6.6~14.2 % efficiency than a general land photovoltaic system.