• 대한전자공학회논문지SD
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• 제39권3호
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• pp.9-19
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• 2002

본 논문에서는 thermionic emission 모델을 이용하여 SCH 양자우물 레이저 다이오드에 대한 L-I-V특성을 해석적으로 도출하였다. SCH의 bulk 캐리어와 양자우물 속박 캐리어의 관계를 도출하였고, 주입된 전류를 각 영역에서의 캐리어 재결합을 고려한 전류 연속 방정식을 만족하도록 하였다. 또한, high level injection과 전하 중성 조건하에 ambipolar 확산 방정식을 이용하여 캐리어 분포를 고찰하였다. 위 해석적인 모델을 이용하여 계산한 결과, 클래딩 영역의 전위장벽 변화가 전류 전압 특성 변화의 주요 원인으로 나타났다. 또한 thermionic emission에 의한 주입 전류의 forward flux 증가가 캐리어 주입을 증가시키고, 레이저 다이오드의 직렬 저항을 감소시키는 것을 보였다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.189-195
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• 1999

We have studied the vortex dynamics in YBa$_2Cu_3O_7$ single crystals with columnar defects using micro Hall-probe array. The Hall-probe array technique allowed a simultaneous measurement of the time and spatial dependence of the vortex density so that more detailed information on flux dynamics could be obtained. We found that field profiles inside sample were similar to the Bean's critical state model from the magnetic hysteresis measurement. Normalized relaxation rates were maximum near the center and decreased toward the edge if applied field H$_{app}$ is greater than the penetration field H. But applied magnetic field H$_{app}$ is less than H, relaxation rates were minimum near the center and increased toward edge. We found that glassy exponent ${\mu}$ has the value of ${\sim}$ 1 whose corresponding vortex motion is half-loop excitation. However, single vortex creep, ${\mu}$ ${\sim}$ 1/7, was also found at 30 K and H$_{app}$ ${\cong}$ H'. Calculation of activation energy, U, was possible from direct analysis of the local relaxation data using the basic diffusion equation. From these results, we found that U increases logarithmically with time and U around center was lower than that at the edge.

• 전자공학회논문지A
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• 제31A권10호
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• pp.87-93
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• 1994

Ohmic contacts between Au and p-HgHg_{0.7}Cd_{0.3}Te$ with low specific contact resistance have been obtained. The contact region of the wafer is first pre-heated for 5 seconds in a rapid thermal processing equipment. The temperature reaches a maximum value of about 200$^{\circ}C$ at the end of the 5 seconds. Next, a thin Au film is formed on the contact region by immersing the sample in AuCl$_{3}$ solution. the sample is then post-annealed in the same condition as the pre-heating after Pb/In pad metals are deposited on the electroless Au contacts. The specific contact resistance measured by transmission line model is 5${\times}10^{-3}{\Omega}cm^{2}$ at 80K. RBS and differential Hall measurement data suggest that the above low resistance ohmic contact is ascribed to surface traps and increased gold diffusion rate.

• 한국안전학회지
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• 제15권1호
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• pp.72-79
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• 2000

In recent, occupational diseases in harmful working places become a social issue. It is the well-known fact that a respiration in polluted working places exert a serious effect on health of workers. Accordingly, the cutting off contaminants air originally is the best way to improve working environments. In these cases, ventilation systems should be essentially installed to dilute or exhaust the contaminated indoor air. In this study, we investigated the characteristics of ventilation system of the noxious gas in working indoor places with natural ventilation by using COMET. The numerical simulations were carried out the natural ventilation with two phase(air, dust). For turbulent flow, Reynolds stresses were closed by the standard $\kappa$-$\varepsilon$ model. The results are as follows ; 1) In the natural exhaust in the working place, the flows of the central region have a more rapid velocity vector than the right and left one. 2) Numerical results show that the distribution of contaminants concentration have greater influence on convection than the case of diffusion by government of velocity vectors. 3) To observe the velocity variation with distance, three location of distance are considered. As results, it shows that the velocity are 0.075(m/s) at y=5(m), 10(m) and mean concentration are raised 10.6% at y=5(m), 10(m). 4) We have presented the useful data for the adequate counterplan in the harmful working places by carrying out the various investigation of the natural ventilation.

• 한국산학기술학회논문지
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• 제19권9호
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• pp.454-464
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• 2018

OECD 분석에 의하면 현재 무형자본이 가장 잘 발달되어 있는 곳은 선진국이다. 무형자본이 경제성장에 긍정적인 영향을 준다는 사실은 이미 많은 연구를 통해 증명되었다. 하지만 같은 무형자본이라 하여도 종류에 따라 경제성장에 미치는 기여도가 다를 수 있다. 본 연구는 이러한 점에 착안하여 무형자본의 특성을 세 가지로 분류하고 차이점을 분석하여 이로부터 시사점을 찾고자 하였다. 무형자본의 종류는 전산화된 정보, 지적재산, 그리고 사업적 역량으로 크게 세 가지로 나누어지는데 본 논문에서는 이 분류를 암묵성의 정도, 생산 및 전파의 속도, 그리고 부가가치의 정도에 따라 새로이 살펴보았다. 본 논문은 Polanyi의 암묵성 정도에 따른 지식 분류, Nonaka-Takeuchi 모델, 그리고 스마일 커브를 이용하여 무형자본의 특성과 차이점을 분석하고, 이를 통해 무형자본 자체에 투자를 늘리는 것도 중요하지만 무형자본 중에서도 가장 암묵적인 특성을 가진 무형자본에 투자하는 것이 경제성장에 더욱 큰 영향을 준다는 점을 도출하였다.

• 정보화정책
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• 제24권1호
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• pp.79-99
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• 2017

빅데이터 관련 기술이 점차 성숙해지고 있고 공공부문을 중심으로 초기 성공사례들이 발표되고 있으나 실질적인 가치 창출에 대한 확신 부족과 개인정보 유출에 대한 여전한 우려로 산업 전반으로의 확산이 더딘 실정이다. 본 연구에서는 빅데이터 도입 과정에서 다양한 이해관계자 집단 별로 긍정적, 부정적 인식이 도입 활성화에 어떠한 차이를 보이는지 탐색적으로 규명하고자 한다. 먼저 기술수용모형(TAM)과 업무기술적합성(TTF) 모형, 프라이버시 계산이론을 바탕으로 긍정적인 평가요인과 부정적인 평가요인을 통합하여 독립변수를 개발하고 빅데이터 이용의도를 종속변수로 하는 연구 모형을 개발하였다. 국내 빅데이터 실사용자 또는 잠재적 사용자를 대상으로 실증 분석한 결과 선행요인 중 빅데이터의 인지된 유용성, 업무기술적합성, 개인정보침해위험이 이용의도에 유의미한 영향을 주고, 사용용이성은 유의성이 없는 것으로 나타났다. 또한 각 요인 별로 빅데이터 활용 주체에 따른 집단 간 변수의 평균 차이를 부분적으로 발견할 수 있었고, 독립변수와 종속변수와의 인과관계에서도 일부 조절효과를 발견하였다. 본 연구의 시사점을 통해 향후 빅데이터의 산업 활성화를 위해서 이해관계자 별 차별화된 정책 개발이 필요한 시점이다.

• 한국IT서비스학회지
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• 제11권4호
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• pp.1-23
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• 2012

The growing interest in smartphones has increased the number of studies conducted on technology acceptance and user satisfaction. It is now over two years since the launching of smartphones, but there are not many researches on the usage behavior of today's smartphone users. Smart devices have evolved from smartphone to smart pad and smart TV, but there are still not many studies on variables such as knowledge about the parent product and the ability to use it. With this, I decided to study how the motivation and the ability of using smartphones affected the smartphone user's intention to use smartpads. This study presents the usage behavior of smartphone users and proves that the ability to use a parent product (smartphone) affects the user's intention to use an extension product (smartpad). The research results showed that the smartphone usage ability affected both variety of use and rate of use. The convenience and passing time factors affected variety of use; and the social interaction, entertainment and passing time factors affected rate of use. As for the intention to use smartpads, the smartphone usage ability and variety of use positively affected the smartphone user's intention to use smartpads. This study showed that the more the user used a smartphone to pass time and for convenience, the more effectively the user could use various functions. It proves that the variety of use of smartphone is highly related to the acceptance of smartpads. This study also proves that usage ability is an important factor in using innovative products, such as smart devices.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제8권11호
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• pp.271-276
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• 2019

LUT 기반의 S-Box를 사용하는 기존의 ARIA 알고리듬은 처리속도는 빠르지만 회로의 크기가 매우 커지게 되어 저면적이 요구되는 소형의 휴대용 기기에는 적용하기 어렵다. 본 논문에서는 하드웨어 면적의 감소를 위해 개선된 합성체 S-Box를 기반으로 한 최적의 ARIA 암호프로세서 설계를 제안한다. ARIA 알고리듬에서의 키 스케쥴링 과정에서 확산 및 치환 계층에서 반복적으로 사용한다. 여기에서는 또한, 키 스케쥴링 과정에서의 사용 면적을 최소화하는 방안으로 치환과 확산 계층에서 하드웨어 자원의 공유 방법을 제안한다. 설계된 ARIA 암호프로세서는 Verilog-HDL을 이용하여 회로를 기술하였고, Xilinx XC3S1500을 타겟으로 하여 논리 합성을 수행하였다. 설계된 시스템의 기능 검증을 위해 Mentor사의 Modelsim 10.4a 툴을 이용하여 논리 및 타이밍 시뮬레이션을 수행하였다.

• 아태비즈니스연구
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• 제12권3호
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• pp.1-36
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• 2021

Purpose - This empirical study, aims to identify the determinants of adoption and acceptance of mobile payment as to understand why it is successful in some countries in Sub-Saharan Africa but failing in others. A comparative study of a successful mobile payment service and a purported failed one was done as to have some insights to the factors affecting acceptance of the technology. Design/methodology/approach - The strength of three notable theories: theory of diffusion of innovation (DOI), the extended unified theory of user acceptance of information technology (UTAUT2) and self-efficacy theory were use. The self-efficacy of government support inclusion as, a moderating variable in the form of infrastructure, securing transaction and price value revealed the relevance of government in the success of mobile payment service. By means of a field survey of 705 subjects in two separate regions of Africa (East and West), the data was collected and use to test the research model. Findings - The study result shows the importance of the moderating factor of government support to the success of mobile payment of any nation. The result also shows the importance of the perception of relative advantage, compatibility, complexity, social influence as already revealed by other studies. Research implications or Originality - Mobile payment success in some part of Sub-Saharan Africa is well known but also suggested to fail in some Sub-Saharan African countries. Buttressing the need for understanding of the factors affecting mobile payment acceptance. This article empirically examined the factors influencing the success of mobile payment, and we implicated that if the implementation of mobile payment is to be successful for mobile commerce in any nation, adoption, acceptance and use by its citizen is imperative.

• International Journal of Computer Science & Network Security
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• 제22권1호
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• pp.340-346
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• 2022

The article examines the formation of the scientific paradigm of transformation of the potential-forming space of the regional economy under the influence of intellectual and innovative determinants. Based on the study of different scientific views on the nature and properties of potential-forming space through the study of approaches to understanding the concept of "space" clarified the complexity and multifaceted nature of the phenomenon and found that its characteristics are relevant to the industrial development model. It is revealed that the leading modern trends related to the spread of globalization and regionalization, rapid development of information and communication technologies, diffusion of innovations accompany the transition from industrial to post-industrial development and its development, which leads to new development: changes production, nature and relations between business entities, etc. It is proved that under such conditions, the region as a key element of the economic system, acquires a leading role in achieving sustainable and balanced development. These processes significantly affect the potential-forming space of the regional economy under the influence of intellectual and innovative determinants, leading to the need for its transformation and change in accordance with modern realities, which is reflected in thorough research on the formation of scientific paradigm based on the formation of its theoretical foundations and methodological basis. This study reveals the essence, role, functions, structure, process of formation of the scientific paradigm of transformation of the potential-forming space of the regional economy under the influence of intellectual and innovative determinants. It is proved that the formation of the modern scientific paradigm of transformation of the potential-forming space of the regional economy under the influence of intellectual and innovative determinants occurs in the context of building a post-industrial model of development, accompanied by consideration of the region as a spatial object territories from the physical plane to the spatial environment in which the development of human capital, innovation and self-development of the region. Taking into account the above, the article outlines the prerequisites and factors of formation of the scientific paradigm of transformation of the potential-forming space of the regional economy under the influence of intellectual and innovative determinants.