• 건축구조
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• 제18권1호
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• pp.68-74
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• 2011

• 과학기술정책
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• 제2권38호통권38호
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• pp.4-7
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• 1992

• Corrosion Science and Technology
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• 제6권4호
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• pp.164-169
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• 2007

Hydrogen induced cracking (HIC) was studied phenomenologically and the effect of microstructure on HIC was discussed for the steels having two different levels of nonmetallic inclusions. Steels having different microstructures were produced by thermomechanically controlled processes (TMCP) from two different heats which had the different level of nonmetallic inclusions. Ferrite/pearlite (F/P), ferrite/acicular ferrite (F/AF), ferrite/bainite (F/B) were three representative microstructures for all tested steels. For the steels with higher level of inclusions, permissible inclusion level for HIC not to develop was different according to steelmicrostructure. On the contrary, HIC occurred also at the martensite/austenite (M/A) constituents regardless of steel microstructure when they accumulated to a certain degree. It was proved that M/A constituents were easily embrittled by hydrogen atoms. Steels having F/AF is resistant to HIC at a given actual service condition since they covers a wide range of diffusible hydrogen content without developing HIC.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.985-994
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• 2004

The application of the reinforced retaining wall has increased in the last 10 years in Korea. The height of reinforced wall is generally limited to less than 15m. It has been reported that the reinforced wall higher than 10m should have higher strength reinforcement or should reduce the lateral earth pressure of the reinforced wall to secure the stability of the wall. In this study, the reinforced retaining wall was constructed 14m high, backfilled by a mixture of soil and cement and instrumented on the reinforcement elements. The instrumented reinforced wall was monitored during and after construction. Field monitoring result shows that a backfill by a mixture of soil and cement reduced the tensile stress developed on the reinforcing elements and the reinforced wall backfilled by a mixture of soil and cement performed successful.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.268-269
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• 2006

The estimation of applicability $SrTiO_3:Pr^{3+}$, Al to a class low-voltage flat-panel displays based on field emission effect, which have average value anode voltage $U_a=300V$ and current density $j=100\;mA/sm^2$ at duty 240, has given positive result. In the same time observably for the most effective sample in similar conditions of excitation high brightness - more than $500\;Kd/m^2$ and linear brightness dependences from current density and voltage allows to decrease greatly the power which consumed by the device.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.79.6-79
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• 2002

We propose here sequential 2 methods for obtain information of current or potential data for power transmission line. One is a digital data transmission unit, this is, an output of a current sensor of power transmission line is digitalized by use of an easy asynchronous protocol. The unit has high speed transform rate, easy making header caused of consisting of only logic circuit. The other is, the output of the unit is transformed via LAN interface and displayed on a personal computer. We have confirmed remote measuring using the method for 100A and 240 A of the current information of power transmission line. Therefore we will be able to see a current waveform by use of internet at a cheep c...

• Wind and Structures
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• 제4권2호
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• pp.131-146
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• 2001

A full-scale synchronized data acquisition system was set up on the roof of the experimental building at the Texas Tech University Wind Engineering Research Field Laboratory to simultaneously collect approaching wind data, conical vortex images, and roof corner suction pressure data. One-second conditional sampling technique has been applied in the data analysis, which makes it possible to separately evaluate the influencing effects of the horizontal wind angle of attack, ${\theta}$, and the vertical wind angle of attack, ${\varphi}$. Results show a clear cause-and-effect relationship between the incident wind, conical vortices, and the induced roof-corner high-suction pressures. The horizontal wind angle of attack, ${\theta}$, is shown to be the most significant factor in influencing the overall vortex structure and the suction pressures beneath. It is further revealed that the vertical wind angle of attack, ${\varphi}$, plays a critical role in generating the instantaneous peak suction pressures near the roof corner.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.404-405
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• 2008

This paper is analyzed that the development of intelligent terminal unit for the switchgear partial discharge diagnosis. It is the core technology for supplying with stable and trust electric as a technology that be economic of the high efficient, the maintain, the confidence and the repair. So the condition diagnosis of the switchgear is necessary by developing inteligent terminal unit.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.418-419
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• 2019

본 논문에서는 Dual-Bridge LLC 공진형 컨버터를 이용한 고효율 PV 스트링 Power Optimizer를 제안한다. 제안하는 Power Optimizer는 LLC 공진형 컨버터를 이용하여 모든 스위치의 ZVS 턴온 및 다이오드의 ZCS 턴오프를 성취하여 고효율을 달성할 수 있다. 또한 컨버터 토폴로지는 하프브릿지 회로와 풀브릿지 회로가 통합된 Dual-Bridge 구조를 적용하여 PV 스트링의 넓은 입력전압 범위(300V-900V) 조건에서도 정전압 출력이 가능하다. 본 논문에서는 6.25kW급 시작품 실험을 통하여 제안하는 Power Optimizer의 타당성을 검증하였다.

• 기술혁신학회지
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• 제16권4호
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• pp.883-912
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• 2013

최근 경쟁우위 확보를 위한 급격한 경쟁 환경 속에서 과학기술혁신 분야의 경쟁력 제고를 위해서는 미래 주도형 원천 융합기술 개발 및 융합신산업을 육성할 수 있는 환경이 구축되어야 한다는 논의가 활발히 진행되고 있다. 이에 융합기술에 대한 지원 확대는 선택이 아닌 필수로 간주되고 있으며, 규모가 커지고 있는 융합기술 관련 R&D에 대한 투자의 효율적인 방향 모색의 필요성도 크게 대두되고 있다. 본 연구에서는 네트워크 분석을 통해서 연구 분야간에 어떤 유기적 관계를 형성하면서 융합연구가 이루어지고 있는지를 분석하였다. 대표적인 융합연구 사업인 첨단융합기술개발사업에 대한 네트워크 분석 결과, 연구 분야들간에 융합이 고르게 연계되어 이루어지고 있는 것으로 나타났다. 그러나 연계의 응집성을 나타내는 밀도분석 결과, 핵심군집에 속한 연구 분야들간에는 강한 연계성을 보이는 반면 핵심과 주변군집간의 연계 분포성은 상대적으로 미약한 것으로 나타났다. 또한 중심성과 연구 분야간 융합과제 비율에 대한 상관관계 분석결과, 연결 중심성이 낮은 분야들에서도 융합연구에 필요한 연구 역량이나 지식 자원을 보유하고 있는 것으로 나타났으며, 중심성이 높더라도 융합연구에 대한 지원 미비로 융합연구 활동이 활성화되지 못하는 경우가 있음을 본 연구결과는 제시하고 있다.