• Journal of Hydrogen and New Energy
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• v.34 no.5
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• pp.456-464
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• 2023

In this study, a compact hydrogen liquefaction system was constructed with the aim of creating a data storage and monitoring program for liquid hydrogen production. This program was designed to receive and record signals from diverse control equipment through the LabVIEW software. A range of measurement instruments were devised to collect data, encompassing variables such as flow rate, pressure, temperature, and liquid level. As a result, it was possible to directly check the production of liquid hydrogen by obtaining various data of condensed liquid hydrogen. In addition, it was confirmed that long-term storage of liquid hydrogen is possible by developing automatic ON/OFF through the LabVIEW program.

• Journal of Hydrogen and New Energy
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• v.34 no.6
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• pp.615-622
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• 2023

In this study, the theoretical analysis focused on the quantity of liquid hydrogen required for cooling down to 20 K, as well as the generation of boil-off gas (BOG) from the cooling process of the cryogenic components. The study involved calculating the amount of liquid hydrogen needed to achieve the desired temperature for the cryogenic components and subsequently determining the resulting BOG production at various reference temperatures. It was shown that it was important to efficiently lower the temperature of cryogenic parts through preliminary cooling. As a result, the reference temperature and pressure had an influence on the BOG generation on the cooling of cryogenic components using liquid hydrogen.

• Journal of Hydrogen and New Energy
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• v.35 no.3
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• pp.280-289
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• 2024

In this study, a cryogenic vessel was constructed to maintain and control the safe pressure of liquid hydrogen boil-off gas (BOG), and the numerical analysis was conducted on the development of computational fluid dynamics model inside the high-pressure vessel. An evaluation system was constructed using cryogenic inner and outer containers, pre-cooler, upper flange, and internal high-pressure container. We attempted to analyze the performance of the safety valve by injecting relatively high temperature hydrogen gas to generate BOG gas and quickly control the pressure of the high-pressure vessel up to 10 bar. As a results, the liquid volume fraction decreased with a rapid evaporation, and the pressure distribution increased monotonically inside a high pressure vessel. Additionally, it was found that the time to reach 10 bar was greatly affected by the filling rate of liquid hydrogen.

• Journal of Hydrogen and New Energy
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• v.35 no.4
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• pp.353-362
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• 2024

In this study, several studies were conducted on the construction of gas conversion process system for a pilot plant using a small-scale hydrogen liquefaction system. The pilot plant considered in this study includes a liquefier, a storage tank, an evaporator, a gas booster, and a gas storage tank. First, the suspected leak area of the container was checked using the sprayed method of helium gas. The small-scale hydrogen liquefaction system was designed based on the analysis results of the pre-cooling system and the liquefaction system. Additionally, the program was developed to maintain pressure within vessel for an automatic production of liquid hydrogen. The evaporator for liquid hydrogen was manufactured based on the designed analysis data, and the pollution of gas in the vessel was analyzed through a gas recovery line system.

• Journal of Hydrogen and New Energy
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• v.35 no.4
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• pp.384-391
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• 2024

In this study, a fuel cell with a single stack of 100 cm² was manufactured and a superconducting coil driving experiment was conducted. Fuel cell activation and performance evaluation were performed, and a method of applying current to a superconducting coil using a fuel cell was considered by controlling the flow rate of gas supplied to the fuel cell. A scenario was created using a specific program to change the amount of gas supplied to the fuel cell over time. As a result of analyzing the voltage and magnetic field of the superconducting coil according to the applied current, it was confirmed that the performance of fuel cell was almost the same with that of power supply.

• Journal of Hydrogen and New Energy
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• v.35 no.4
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• pp.392-400
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• 2024

In this study, 3-cell stack fuel cell power technology was developed for charging superconducting coil. It was found that the performance of the fuel cell stack increased depending on the number of activation. In addition, the flow rates of hydrogen and air supplied to 3-cell stack was adjusted because of a large difference in membrane electrode assembly (MEA) characteristics depending on its location. As a result, it was confirmed that it was possible to apply current to the superconducting coil from about 15 to 33 A by changing the variable resistance, and it was confirmed that the voltage difference between fuel cell cells could be overcome through sufficient control of fuel supply.

• Electric Engineers Magazine
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• v.257 no.1
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• pp.24-32
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• 2004

공연장은 문화적 공간이기에 앞서 많은 사람이 동시에 운집하는 대규모 집회시설이며, 그 특성상 복잡한 내부공간 및 다양한 용도로 인해 전기화재 등의 사고발생시에는 재산피해는 물론 많은 인명피해가 우려되는 대표적인 다중 이용시설 중의 하나이다. 또한 눈부신 과학기술의 발전으로 공연장의 설비도 첨단화·다양화되고 있는데 반하여 국내의 경우 아직도 공연장 등 연출공간이 지닌 특수성으로 인해 전기안전이 제대로 반영되지 않은 채 전기설비가 시설되고 있으며 관련전기법규 등도 아주 간단히 규정하고 있어 공연장의 안전대책은 매우 중요한 문제로 부각되고있다. (중략)

• Electronics and Telecommunications Trends
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• v.27 no.3
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• pp.186-195
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• 2012

전기자동차는 석유 연료와 엔진을 사용하지 않고, 전기 배터리와 전기모터를 사용하는 자동차이다. 그동안 전기자동차는 가솔린 자동차보다 오랜 역사를 갖고 있었으나 배터리 중량, 충전 시간 등의 문제로 인해 실용화되지 못했다. 그러나 최근 들어 경제성과 친환경성을 만족시키면서 GM, 르노 등을 중심으로 전기자동차가 시판되고 있고, 국내에서도 활발히 개발되고 있다. 본고에서는 미국, 일본, 유럽, 중국과 국내의 전기자동차 관련 정책을 살펴보고 정책적 시사점을 도출하고자 한다.

• JOURNAL OF ELECTRICAL WORLD
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• no.7 s.1
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• pp.66-68
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• 1965

5월 12일로부터4일간에 걸쳐 동경에서 개최되었던 일본전기협회 제44회 통상총회에는 우리나라에서도 대한전기협회를 대표해서 한전의 진의종 부사장과 김종수 이사가 참석한 바 있다. 아래에 소개하는 글은 동 총회에 참석하였던 미국의 Walker L. Cisler씨(Detroit Edison Co. 회장$\cdot$Edison전기협회 회장$\cdot$Thomas Alva Edison재단 이사장)의 연설 전문이다. 선진제국과의 교류를 통하여 우리나라의 전기관계사업의 발전향상을 촉진하고자 함이 우리 대한전기협회의 설립목적의 하나임을 상기하면서 제자 여러분께서 많이 읽어 주실 것을 기대해 본다.

• JOURNAL OF ELECTRICAL WORLD
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• s.458
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• pp.56-59
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• 2015

올해 국내 전기산업의 총 수출액이 사상 최초로 150억 달러를 돌파할 전망이다. 예상대로 되면 2011년 100억 달러를 돌파한지 4년 만에 50% 급상승이라는 신기원을 기록하게 된다. 수출과 달리 내수는 상당히 힘든 한 해를 보낼 것으로 보인다. 한전의 수요 증가 등 긍정적 측면도 있지만, 조선 철강 등 관련 산업의 부진이 악영향을 미칠 가능성이 더 크다는 분석이다. 한국전기산업진흥회는 최근 이 같은 내용을 담은 '2015년 전기산업 동향 및 전망' 보고서를 발표했다. 주요 내용을 정리해봤다.