• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권9호
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• pp.466-470
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• 2001

We have developed a sub-micron gap fabrication technology using chemical-mechanical polishing (CMP) without /the sub-micron lithography equipments (0.18∼0.25 7m). And it has been applied to a lateral field emission device (FED), in which narrow gap distance is very important for reducing turn-on voltage. As a result, the turn-on voltage (at which the current level is 1 nA) of the fabricated device with the gap distance of 256 nm is as low as 4.0 V, which is the lowest turn-on voltage among lateral FEDs ever reported.

• Journal of Magnetics
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• 제11권3호
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• pp.139-142
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• 2006

We fabricated new one-dimensional magnetophotonic crystal (1D-MPC) utilizing the second and third photonic band gaps where localized modes existed. Structure of the 1D-MPC was $(Ta_{2}O_{5}/SiO_{2})_{5}/Bi:YIG/(SiO_{2}/Ta_{2}O_{5})_{5}$ with optical thicknesses of 3$\lambda$ /4 for $Ta_{2}O_{5} and $SiO_2$ dielectric layers and $\lambda$ /2 for Bi:YIG defect layer, where $\lambda$ is a wavelength of a localized mode in the second photonic band gap. Faraday rotation at the localized mode in the second photonic band gap was enhanced, which was confirmed by calculation using 4${\times}$4 matrix method.

• 한국식품위생안전성학회지
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• 제31권6호
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• pp.414-419
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• 2016

본 연구는 상추와 오이의 GAP 인증 및 미인증 농가를 대상으로 토양, 용수, 작물 (상추, 오이), 장갑, 포장재 (비닐)에 대한 미생물 오염도를 비교 평가하고 농가의 위생관리 실태를 조사하여 GAP 인증 농가에 대한 미생물학적 안전성 강화를 위한 자료로 활용하고자 하였다. 미생물 오염도 조사 결과 상추 농장의 경우 위생지표세균 오염도는 GAP 인증 농가가 미인증 농가 보다 조금 낮거나 유사하였고, 병원성미생물인 S. aureus와 B. cereus는 GAP 인증 농가의 토양과 용수에서 미인증 농가 보다 높게 검출되었다. 오이농장은 토양의 대장균군과 B. cereus, 장갑의 일반세균 및 대장균군 오염도가 GAP 미인증 농가보다 GAP 인증 농가에서 높았고, 그 외에는 GAP 인증 농가와 미인증 농가가 유사한 오염도를 나타내었다. 전체적으로 결과를 비교했을 때 GAP 인증 농가와 미인증 농가의 미생물 오염도 수준이 크게 차이가 나지 않는 것으로 확인되어 GAP를 인증 받았음에도 불구하고 미생물에 대한 관리는 미흡한 것으로 나타났다. 농가의 위생관리 실태 조사 결과에서는 GAP 인증 농가가 미인증 농가보다는 미생물 오염을 방지하기 위한 노력들을 하고 있는 것으로 확인되었으나, GAP 인증 및 미인증 농가 모두 농업용수의 관리와 작업 시 사용되는 작업자의 장갑 관리에 있어서는 미흡한 것으로 확인되었다. 이상의 연구결과는 농산물의 미생물 오염방지에 대한 방안을 제시하고 GAP 인증을 개선하는데 기초자료로 활용될 수 있을 것으로 판단된다.

• Management Science and Financial Engineering
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• 제16권2호
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• pp.17-27
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• 2010

The customer churn and the forecast of customer churn have been important research topics for a long time in the academic domain of customer relationship management. The customer value is studied to construct a gap model based on dual customer values; a basic description of customer value is given, then the gaps between products and services in different periods for the customers and companies are analyzed. The main factors that influence the perceived customer value are analyzed to define the "recognized value gap" and a gap model for the dual customer value is constructed. Based on the dual customer gap a con-ceptual model to determine potential churn customers is proposed in the paper.

• JSTS:Journal of Semiconductor Technology and Science
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• 제6권3호
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• pp.175-181
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• 2006

Wide band-gap semiconductor electron devices have made great progresses to produce very high power amplifiers for various wireless standards. The advantages of wide band-gap electronic devices and their progresses are summarized in this paper.

• 정보저장시스템학회논문집
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• 제3권1호
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• pp.1-4
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• 2007

A high density optical data storage device has been required for many years. In the field of the optical data storage, a near-field recording (NFR) technology is considered as a next generation one for achieving the high data density. Due to an evanescent wave effect occurred under 100nm distance which is the excessively small distance between the SIL and the disc, the most significant and difficult problem in this technology is to maintain a gap between a solid immersion lens (SIL) and a disc. Also, maintaining the gap under at least 50nm is required in the NFR gap servo system to use the evanescent wave effect efficiently. There are some institutes that have shown the novel gap servo control. In general, they use a mode switching servo method which consists of approach, hand-over and gap control mode. However there is a critical problem such as an overshoot at the tuning point from the approach mode to the hand-over mode, which may cause a collision between the SIL and the disc. In this paper, we show our NFR system and an improved gap servo system using an exponential function as the approach mode which can reduce the overshoot.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.5-15
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• 2007

A welding structures is generally composed of dissimilar steel materials in order to reduce weight cost, and has a gap to fill the welding agent. Also, heat flow analysis should be fulfilled for structure existing of gap to figure out residual stress which is generated after welding. Since mechanical properties of welding structure composed of dissimilar steel is more fragile than mechanical properties of welding structure consisted of same material, heat flow analysis verifying this should be fulfilled as well. Therefore, on this research, heat flow analysis about dissimilar steel weldment consisted of gap existing AISI304 and AISI630 is practiced so that it could be a basic data of research about mechanical properties of gap existing dissimilar steel welding part which is going to be studied later on. During heat flow analysis, heat input model which based on Gaussian profile and using volume heat flux was newly consisted and applied. In addition, for verifying of analysis on this research, gap existing dissimilar steel weldment which had gap of 0.25mm and was welded using Nd-YAG. The welding profile and temperature distribution for weldment during welding was compared to the result which was gotten through heat flow analysis. Both of those results corresponded each other.

• Journal of Information Technology Applications and Management
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• 제24권2호
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• pp.97-112
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• 2017

This paper aims to research the technology level of sports industry, through analyzing the technology gap between Korea and other major countries (USA, Europe, Japan, and China), and provide a list of technologies to be prioritized for R&D investment by conducting an analysis of the strategic importance of various element technologies. The results of the analysis showed that the technology level of Korean sports industry currently stands at 70.5% of the country with the most advanced technology (the USA), and that the technology gap amounts to 4.8 years. It was also found that the USA is the country with the most advanced technology (100%) at present, followed by Europe (91.1%), Japan (88.3%), Korea (70.5%), and China (61.2%). To reduce the technology gap, we established a Strategic Zone (SZ) and derived three element technologies including 'design and production technologies for sports and game equipment' in the $1^{st}$ tier, nine element technologies including '3D motion analysis and simulation technology' in the $2^{nd}$ tier, and four element technologies including 'fitness/health promotion and management technology' in the $3^{rd}$ tier. The significance of this research is that it included five major technology categories of the sports industry in its analysis, selected an expert on sports industry technologies using the delphi method. Therefore, the results of this study may be suitable for use as basic data in establishing the R&D strategy for the future development of the sports industry.

• Journal of Magnetics
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• 제18권3호
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• pp.260-267
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• 2013

In this paper a general 2-D model of a large air-gap synchronous machine either with non-magnetic or magnetic core rotor is investigated and electrical characteristics of the machine are analytically calculated. Considering the general model, analytical equations for magnetic field density in different regions of the large air-gap machine are calculated. In addition, self and mutual inductances in the proposed model of the machine have been developed, which are the most important parameters in the electromagnetic design and transient analysis of synchronous machines. Finite element simulation has also been performed to verify the obtained results from the equations. Analytical results show good agreement with FEM results.

• 기술혁신학회지
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• 제6권2호
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• pp.191-202
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• 2003

The objective of this study is to examine the existence of technology gap convergence between manufacturing sector and Grand Total over 1970 to 2000 under nonlinearity relationship in Korea. We use the concept of technology convergence as the stationarity test of technology gap over the relevant periods. Our empirical results provide two important implications for the future study: First, our empirical results strongly support the nonlinearity for technology convergence in our country and an empirical tests based on the assumption of linearity will be biased and wrong industry and economic policy implications. Second, we find two regimes i.e. technology convergence and technology divergence between manufacture sector and Grand Total in our country over 1970 to 2000. These study results imply that the relevant industry and economic policies for technology and R&D implementations be with a causation.