• 전기학회논문지P
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• 제60권4호
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• pp.175-180
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• 2011

A large AC generator is an important component of the power system. It is a need for research of AC generator protection relay for the next-generation ECMS and an efficient operation of protection control system. However, most of protection and control systems used in power plants have been still imported as turn-key and operated in domestic. This may cause the lack of the correct understanding on the protection systems and methods, and thus have difficulties in optimal operation. In this paper, over-excitation protection relaying is one of the protective factors in generator protection IED was presented. The cause and protection principles were dealt and, DFT-based gain compensation algorithm was adopted for the frequency measurement. The Republic of Korea 345kV modeling data by EMTP-RV was used for performance evaluation.

• Journal of information and communication convergence engineering
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• 제8권1호
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• pp.107-111
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• 2010

This paper has presented the dependence of the threshold voltage on back gate bias and drain voltage for FinFET. The FinFET has three gates such as the front gate, side and back gate. Threshold voltage is defined as the front gate bias when drain current is 1 micro ampere as the onset of the turn-on condition. In this paper threshold voltage is investigated into the analytical potential model derived from three dimensional Poisson's equation with the variation of the back gate bias and drain voltage. The threshold voltage of a transistor is one of the key parameters in the design of CMOS circuits. The threshold voltage, which described the degree of short channel effects, has been extensively investigated. As known from the down scaling rules, the threshold voltage has been presented in the case that drain voltage is the 1.0V above, which is set as the maximum supply voltage, and the drain induced barrier lowing(DIBL), drain bias dependent threshold voltage, is obtained using this model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.404-409
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• 2002

A newly devised linear flexure bearing (KIMM-LFB) for reciprocating machines is disclosed having improved tight gas clearance maintaining capability for better system performance. KIMM-LFB is an integrated device comprising an axially moving diaphragm with circumferentially arranged arc-shaped flexure blades secured between rim and hub spacers, which turn out to have higher radial stiffness than the one with circumferential tangent cantilever flexure blades. It is expected for KIMM-LFB to play a key role in designing long life, special purpose reciprocating machines such as spacecraft borne cryogenic refrigerators (cryocoolers) by providing frictionless, non-wearing, linear movement and radial support for the machines as well as a gas clearance seal by maintaining extremely tight clearances between piston and cylinder.

• 경영과학
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• 제15권1호
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• pp.13-31
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• 1998

In this paper, we examine the relationship between information type and new product development process. Information that was provided for new product development can be divided into two categories. One was relative information that could be used as a basis for comparison such as patent data. The other was absolute information that must be fulfilled in the new product such as key customers requirements. An experiment was conducted with staffs in an R＆D department in order to analyze the impact of the different information types on the development process of new product. It was found that the group with the absolute information recognized the given information repeatedly, which in turn results in a highly technical idea with good teamwork. The group with the relative information created a superior product with better application, appearance and product efficiency through the frequent refinements of given ideas. This paper concludes with the implications of the results to the new product development process and supporting information systems.

• 전기의세계
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• 제25권6호
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• pp.19-25
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• 1976

수출진흥책에 부응하여 중동지역에서도 송전선공사를 수주할 목적으로 필자는 1975년 IRAN국을 방문했으나 허사로 돌아갔고 1975년말 Kuwait국에 출장간 것은 성공하였다. 중동의 산유국은 단시일내에 조국을 근대화하여 선진공업국의 대열에 참여하기 위하여 각종산업분야에 걸쳐서 활발한 건설사업을 벌리고 있다. 따라서 세계각국의 유명한 건설업체는 중동지역에 진출을 하였고 한국에서도 다수의 건설업체가 항만, 도로, 건축분야에 진출하고 있다. 그러나 일반에 잘 인식되어 있지 않은 송전분야가 이러한 대열에 참여할 수 있는 기회를 가지게 되었다는 것은 우리나라 전력계도 타분야에 지지 않는 기술수준과 공사실력을 가지고 있다는 것을 과시할 수 있어 전기인의 한 사람으로서 참 반가운 일이라 아니할 수 없다. 본문은 중동지역에 송전선로의 건설공사를 수주키 위하여 Iran국에 2회, Kuwait국에 2회 여행간 관계로 중동지역의 송전계통에 다소 친숙해진 부문을 소개하고자 한다. 그리고 Turn-Key base로 실시되었던 공사입찰사항에 대해서도 언급하고자 한다.

• 한국컴퓨터정보학회논문지
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• 제21권3호
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• pp.17-23
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• 2016

In this paper, we propose a model of the collaborative authoring tool and its implementation results. In the 'collaborative authoring and automatic distribution system,' users can create eBooks by using partial works (primary and edited sources) on the basis of copyright information registered by the primary author. The Collaborative Authoring Tool is a part of "the collaborative authoring and automatic distribution system" developed through research on "the development of key technologies of social work protection and content mashup tools" as an R&D project granted by the Korea Copyright Commission from 2013. In the collaborative authoring and automatic distribution system, authors of primary sources such as images, audio clips and video clips for eBooks can register them together with the copyright information; users can edit the primary sources to produce secondary sources and in turn register the secondary sources on the system; and users can create and distribute eBooks by using the sources registered in the system.

• Carbon letters
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• 제12권4호
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• pp.218-222
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• 2011

Well-aligned multi-walled carbon nanotubes (MWCNTs) were successfully synthesized by catalytic chemical vapor deposition using a hydrogen sulfide ($H_2S$) additive onto Al/Fe thin film deposited on Si wafers. Transmission electron microscopy images indicated that the as-grown carbon products were thin MWCNTs with small outer diameters of less than 10 nm. $H_2S$ plays a key role in synthesizing thin MWCNTs with a large inside hollow core. The well-aligned thin MWCNTs showed a low turn-on voltage of about 1.1 V/${\mu}m$ at a current density of 0.1 ${\mu}A/cm^2$ and a high emission current of about 1.0 mA/$cm^2$ at a bias field of 2.3 V/${\mu}m$. We suggest a possible growth mechanism for the well-aligned thin MWCNTs with a large inside hollow core.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.855-858
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• 2003

Carbon nanotubes (CNTs) were grown on Ni-coated TiN/Si substrate by microwave plasma chemical vapor deposition using mixture gas of $H_2/CH_4$ at low temperature of 500 $^{\circ}C$. Average diameter of CNTs could be easily controlled by $H_2$ plasma pretreatment time before CNTs growth. The turn-on voltages of CNT emitters were varied from 3.5 $V/{\mu}m$ to 9 $V/{\mu}m$ according to the hydrogen pretreatment conditions. The close relationship between electron emission characteristics and pretreatment time indicates that pretreatment condition can be a key process parameter in CNTs growth for field emission displays..

• BMB Reports
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• 제50권9호
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• pp.435-436
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• 2017

Primed human pluripotent stem cells (hPSCs) are highly dependent on glycolysis rather than oxidative phosphorylation, which is similar to the metabolic switch that occurs in cancer cells. However, the molecular mechanisms that underlie this metabolic reprogramming in hPSCs and its relevance to pluripotency remain unclear. Cha et al. (2017) recently revealed that downregulation of SIRT2 by miR-200c enhances acetylation of glycolytic enzymes and glycolysis, which in turn facilitates cellular reprogramming, suggesting that SIRT2 is a key enzyme linking the metabolic switch and pluripotency in hPSCs.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2004년도 춘계 학술발표회 논문집 제1권1호(통권1호)
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• pp.255-263
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• 2004

광명시 경륜 경기장은 국민 체육진흥공단에서 턴키(Turn key)공사로 발주하였고, CS구조+공간건축+대우건설, 삼성건설, 태영건설의 제출안이 당선되어 현재 시공중에 있다. 경기장의 저층부는 PC로 설계되었고, 지붕은 철골 트러스를 사용한 Dome 형상으로 이루어져 있다. 돔 지붕의 개념은 지붕에 물을 부었을 때 가장 흘러가기 쉬운 방향으로 트러스를 배치하여 유연한 힘의 흐름을 유도하는 것이다. 143.6m(폭)${\times}$183.5m(길이)${\times}$21m(높이)의 지붕엔 지붕의 개념인 Flow Truss를 물이 흐르는 방향의 방사형으로 배치하고, 내부에 압축링(Compression Ring Truss)과 외부에 인장링(Tension Ring Truss)를 설치하여 힘의 흐름을 단순화시켰고, 실내에서 보기에 플로우 트러스의 간격을 넓게 유지함으로써 개방감을 극대화시켰다. 또한 Flow Truss는 동일한 곡률과 길이로 설계하여 표준화시킴으로써 시공성과 경제성을 동시에 만족토록 하였다. 현재 저층부 시공은 거의 완료된 상황이고, 곧 지붕을 설치할 예정이다. 본 고에서는 돔 지붕의 형성 개념과 설계 과정을 살펴보고, 접합상세 등의 해결에 대해 살펴보겠다.