• 한국전자거래학회지
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• 제3권1호
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• pp.155-173
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• 1998

In this paper we present the development of internet banking and its impact on financial market. The internet banking has been introduced since 1990s, from which customers could obtain most financial services over internet, and will replace with the traditional banks. According to a survey, most of bankers agree that internet will play an important role in banking industry. The internet banking has an enormous impact on the transfer system and banking industry. The transfer system is divided into two-large-value transfer system and small-value transfer system, depending on the size of its transfer amount. The internet banking will enhance the transfer system, especially small-value transfer system. It will reduce the time lag between transaction of service and its payment. However, a congestion or a blockage in a part of network might stop the financial service all over the network, which is called "computer risk". As internet banking develops, banks have incentives to reduce their branches and have to compete with information-business companies which can offer financial EDI.

• 전력전자학회논문지
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• 제25권3호
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• pp.181-187
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• 2020

In this study, we propose a spherical flux concentration structure for omnidirectional wireless power transfer. Omnidirectional wireless power transfer technology is a method that can transmit power to a transmitter located in an arbitrary position in a two-dimensional or three-dimensional space. However, to improve the power transfer distance in a wireless power transfer system, the diameter of the coil or the number of windings must increase, thereby increasing the size of the transmitter. The proposed transmitter structure adds a ferrite core inside the transmitter coil so that the magnetic flux generated by the transmitter is directed toward the position of the receiver. As a result, the flux linkage and the mutual inductance increase. By implementing the omnidirectional wireless power transfer system using the proposed structure, the power transfer distance can be improved by 65% compared with the conventional system without increasing the size of the transmitter. Simulation shows that the proposed spherical flux concentration structure increases the mutual inductance of the omnidirectional wireless power transmission system.

• 한국철도학회논문집
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• 제17권4호
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• pp.228-232
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• 2014

철도의 무선전력전송 시스템을 구현하는데 있어 급전선로에서 생성된 자기장은 레일에 유기전압을 형성한다. 레일의 유기전압은 궤도회로의 동작 및 안전사고에 영향을 줄 수 있기 때문에 최소화하는 것이 필요하다. 본 논문에서는 3가지 무선전력전송 선로에 대해서 레일에 형성되는 유기전압의 관계를 시뮬레이션을 통하여 살펴보고 레일 유기전압을 줄이기 위한 급전선로의 자기장 분포를 제시한다.

• 한국물환경학회지
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• 제26권6호
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• pp.1008-1015
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• 2010

Discharged pollution load is varied as rainfall changes in the area with combined sewer system. Changes in discharged pollution load are directly related with those of sewer transfer flow. Therefore, it is important to identify the pattern of sewer transfer flow for the analysis of changes in discharged pollution load. This study reviewed the type of distribution of sewer transfer flow for 17 sewage treatment plants and developed simple formular to estimate sewer transfer flow as rainfall changes. 11 facilities showed to have some relation with rainfall in the change of sewer transfer flow but 6 facilities to have no relation. Relationships between rainfall amount and sewer transfer flow showed that 6 facilities out of 11 had relatively strong relationships above R2=0.5, which were considered to be affected directly by rainfall changes. The formular which explain the relationship between rainfall and sewer transfer flow can be applied in the analysis of rainfall effects on discharged pollution load, therefore, the more appropriate evaluation will be done.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.1000-1004
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• 2008

As performance of medical air compressor improve, the problem of noise increased. Noise is very important to medical air compressor because most of this installed inside of building. The main goal of this paper is show TPA (Transfer Path Analysis) result for contribution analysis using PAK system. Generally, the conventional TPA method consists of two steps. First, transfer functions between output sound and sources are measured by excitation experiment. Second, transferred sound in each transfer path is generated by multiplying the transfer function and the sound source signal. Then, if the output sound synthesized from all transferred sounds doesn't give good agreement with the measured output sound (i.e., the accuracies of the transfer functions are low), setting a suitable countermeasure guideline becomes difficult. For obtaining highly accurate transfer functions, eliminating correlations among transfer functions and noise included in the measured data are necessary. In the new method with PAK system, the vibration acceleration and sound signals around the sound sources and the output sound were measured simultaneously to obtain the transfer functions when compressor was operating. By applying PAK system, a highly accurate and efficient transfer path analysis method was developed that does not require an excitation experiment.

• 한국도로학회논문집
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• 제16권4호
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• pp.51-62
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• 2014

PURPOSES: This research is a basic study for application method in korea of energy harvesting technology, and it is a research to find out the direction of architectural planning through analyzing cases of interseasonal heat transfer system applied buildings. METHODS : In this paper authors investigate application necessity of energy harvesting technology, we analyzed energy use status of building section through analyzing domestic energy consumption status and analyzed domestic renewable energy generation potential. Also we study the features of energy harvesting technology, interseasonal heat transfer system, and case study on interseasonal heat transfer system applied buildings. RESULTS : On the basis of case study on interseasonal heat transfer system applied buildings, we analyzed feasibility study and classified into four sections(economic, environment, design, applicability), and suggested directions of architectural planning. CONCLUSIONS: Economic renewable energy for public and commercial buildings(hospitals, offices, schools, factories) can be provided effectively using Interseasonal Heat Transfer.

• 벤처창업연구
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• 제7권1호
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• pp.165-175
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• 2012

최근 21세기 세계 경제가 지속적인 성장을 유지하기 위한 핵심요소로서 기술의 축적, 이전, 흡수, 상용화 등이 중요하게 인식되고 있으며, 정부는 공공연구기관에서 개발된 기술이 민간부문으로 이전되어 사업화되는 것을 촉진하고 민간부문에서 개발된 기술이 원활히 거래되고 사업화되는 것을 촉진하기 위해'기술의 이전 및 사업화 촉진에 관한 법률'을 마련했다. 또한 동 법률 제14조에서는 기술거래사의 등록 육성 및 지원에 관한 사항으로 '기술거래사' 자격제도를 도입하여 국가에서 등록, 운영, 관리하고 있으며 대부분의 선진국은 기술거래중개 기관을 민간에 이양하여 기술중개기관 또는 기술브러커로 지칭하고 있다. 국내에서는 이러한 자격제도 도입과 시장 활성화 촉진을 위한 다양한 조직과 기술중개시스템을 구축하였음에도 불구하고 기술거래사 등록제도와 사후관리에 대한 법률적 근거와 체계가 미흡하여 문제점이 발생되고 있다. 일례로 최근 기술거래관련 실적면제로 기술거래사 등록 활성화는 달성하였으나, 실적 검증을 통한 일정수준 이상의 전문가 선별에는 한계점이 나타나고 있다. 이에 경력증명서 기재 내용만으로 업무 경력 보유 여부를 판단하기에는 심사의 한계점이 드러나고 있어 이에 대한 대책이 시급하다. 또한 기술거래사 등록 시 의무적 교육이수제도가 2010년도에 법 개정 및 고시 개정으로 마련되었으나, 소양교육수준의 단기 교육과정 운영으로 신청자에게 다양한 전문지식 취득의 기회 제공이 어려움이 있는 것이다. 이에 본 연구에서는 한국과 중국의 기술거래사 제도 비교를 통해 기술거래사 제도개선에 대해 고찰해 보았다. 이를 통해 기술이전 사업화 시장 확대와 기술거래사 전문가의 업무영역 보장과 전문가로서의 입지확보 등 경쟁력을 강화하는데 활용될 수 있도록 개선안을 제시하였다.

• 태양에너지
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• 제19권2호
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• pp.29-36
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• 1999

Heat transfer characteristics of a low temperature latent heat storage system during the heat storage stage was examined for the circular finned tubes using fatty acid which shows the big density difference during melting as phase change materials. The heat storage vessel has the dimension of 530 mm height, 74 mm inside diameter and inner heat transfer tube is 480 mm in height and 13.5 mm outside diameter. Hot water was employed as the heat transfer fluid. During the heat storage stage, it was found that both conduction and natural convection were the major heat transfer mechanism. It was also found that the effect of natural convection on the heat transfer was more significant for the unfinned tube system than that for the finned tube system. The experimentally determined overall heat transfer coefficients were in the range of $50{\sim}250W/m^2K$ and the correlation for natural convection heat transfer as a function of Nusselt and Rayleigh number was proposed.

• Nuclear Engineering and Technology
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• 제46권3호
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• pp.363-372
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• 2014

In this study, we proposed a newly designed sulfuric acid transfer system for the sulfur-iodine (SI) thermochemical cycle. The proposed sulfuric acid transfer system was evaluated using a computational fluid dynamics (CFD) analysis for investigating thermodynamic/hydrodynamic characteristics and material properties. This analysis was conducted to obtain reliable continuous operation parameters; in particular, a thermal analysis was performed on the bellows box and bellows at amplitudes and various frequencies (0.1, 0.5, and 1.0 Hz). However, the high temperatures and strongly corrosive operating conditions of the current sulfuric acid system present challenges with respect to the structural materials of the transfer system. To resolve this issue, we designed a novel transfer system using polytetrafluoroethylene (PTFE, $Teflon^{(R)}$) as a bellows material for the transfer of sulfuric acid. We also carried out a CFD analysis of the design. The CFD results indicated that the maximum applicable temperature of PTFE is about 533 K ($260^{\circ}C$), even though its melting point is around 600 K. This result implies that the PTFE is a potential material for the sulfuric acid transfer system. The CFD simulations also confirmed that the sulfuric acid transfer system was designed properly for this particular investigation.

• 한국농공학회지
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• 제32권E호
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• pp.80-87
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• 1990

Energy balance equations Were developed to describe the heat transfer mechanisms in a double layer plastic greenhouse with a water curtain system. Heat transfer variables were determined by using various temperature data measured in a conventional prototype semicircular cross-section greenhouse over a range of water temperatures and water flow rates. The heat transfer coefficient between flowing water and greenhouse air was independent of water flow rates. But the heat transfer coefficient between water surface and the stagnant air space within the double plastic layer was dependent on water flow rates. Substituting the heat transfer coefficients, determined from the energy balance equations in the heat transfer equations, demonstrated various relationships among ambient air temperature, greenhouse air temperature, water temperature, and water flow rates. The heating benefits were linearly related to not only the inside and outside air temperatures but also to the water temperature. The energy conservation effects of the water curtain system were found even initial water temperatures were considerably lower than the greenhouse setting temperatures. Sensitivity analysis for heat transfer coefficients demonstrated that the heat transfer coefficient between greenhouse air and the stagnant air within the plastic layers was the most significant coefficient in the estimation of heating effects.