• 에너지공학
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• 제13권1호
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• pp.1-11
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• 2004

가스화기술은 전세계적으로 수소에너지 사회로 진입하는 과정에서 필요한 대량수소 공급체계를 구축하는데 중단기적으로 필요한 기술이다. 장기적으로는 풍력이나 태양광과 같은 순수한 재생가능에너지에 기반한 수소공급 체계로 발전될 것이나, 향후 10-20년간 대량수순 제조가 필요하다면 경제성이 있는 기술을 $CO_2$ 발생이 최소화되면서 효율도 높은 기술로 발전시켜 적용하는 방향으로 진행될 것이다. 특히, 국내에서는 천연가스, 석탄, 중질잔사유, 폐기물, 바이오매스 등의 원료로부터 출발한 수소제조가 경제적인 측면에서 유리하므로 최소한 중단기적으로는 활용될 것으로 보인다 수소에너지 이슈가 부각되는 배경중의 하나가 기후변화협약에 대응한 $CO_2$저감의 필요성이므로, 이들 중단기적으로 활용될 원료들의 수소제조기술들은 반드시 $CO_2$저감이 가능한 기술로서 개발되어야 한다.

• 한국전산구조공학회논문집
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• 제35권6호
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• pp.325-331
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• 2022

금속의 취성화는 수소와 접촉하는 구조물을 안정적으로 설계하는데 있어서 큰 문제가 되어왔다. 본 논문에서는 분자동역학 해석을 통해 균열선단 주변에 모인 수소원자들이 전위 이동 현상을 억제하고, 이로 인해 벽개 파괴 현상이 발생하는 것을 확인하였다. 다양한 수소 농도, 하중 속도, 수소 확산 속도 등을 바꾸어가며 분자동역학 해석을 수행하였고, 이에 따른 수소 취성화를 최소화시킬 수 있는 조건들을 조사하였다. 분자동역학 해석 결과는 기존의 실험결과와 잘 일치하였으며 이를 바탕으로 수소 취성화 현상을 정량화하여 평가하였다.

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.137-143
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• 2021

As an electrochemical water electrolysis for green hydrogen production, both polymer electrolyte membrane (PEM) and alkaline electrolyte are being developed extensively in various countries. The PEM electrolyzer with high current density (above 2 A/cm²) has the advantage of being able to design a simple structure. Also, it is known that it has high response to electrical output fluctuations. However, the cost problem of major components is the most important issue that a PEM electrolyzer must overcome. Instantly, there are platinum group metal (PGM)-based electrocatalysts, fluorine-based polyfluoro sulfuric acid (PFSA) membrane, Ti felt (porous transport layer, PTL) and so on. Another challenging issue is productivity. A securing outstanding productivity brings price benefits of the electrolytic cells. From this point of view, we conducted basic studies on manufacturing electrode and membrane electrode assembly (MEA) for PEM electrolyzer production.

• 한국수소및신에너지학회논문집
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• 제30권4호
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• pp.356-361
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• 2019

Since the government announced the roadmap to revitalize the hydrogen economy, we are constantly making the effort to expand the use of fuel cell electric vehicles (FCEV) and hydrogen charging stations. There is however a significant issue to build and operate the hydrogen charging station due to the lack of the profit model. Many researchers believe that the supply of FCEV will be increased in the near future and finally ensure the economy of hydrogen charging stations. This study shows that the sales changes of hydrogen gas and consumption patterns by the operation of the hydrogen charging station in Changwon City. The results will be used as the evidence to support for operating the hydrogen charging station by private businesses and the validity of additional establishment of hydrogen charging stations.

• 한국수소및신에너지학회논문집
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• 제33권4호
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• pp.391-399
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• 2022

Hydrogen is one of the energy carriers and has high energy efficiency relative to mass. It is an eco-friendly fuel that makes only water (H₂O) as a by-product after use. In order to use hydrogen conveniently and safely, development of production, storage and transfer technologies is required and attempts are being made to apply hydrogen as an energy source in various fields through the development of the technology. For transporting and storing hydrogen include high-pressure hydrogen gas storage, a type of storage technologies consist of cryogenic hydrogen liquid storage, hydrogen storage alloy, chemical storage by adsorbents and high-pressure hydrogen storage containers have been developed in a total of four stages. The biggest issue in charging high-pressure hydrogen gas which is a combustible gas is safety and the backfire prevention device is that prevents external flames from entering the tank and prevents explosion and is essential to use hydrogen safely. This study conducted a numerical analysis to analyze the performance of suppressing flame propagation of 2, 3 inch flame arrestor. As a result, it is determined that, where the flame arrestor is attached, the temperature would be lowered below the temperature of spontaneous combustion of hydrogen to suppress flame propagation.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.56-56
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• 2018

Transparent conductive oxides (TCOs) have attracted attention due to their high electrical conductivity and optical transparency in the visible region. Consequently, TCOs have been widely used as electrode materials in various electronic devices such as flat panel displays and solar cells. Previous studies on TCOs focused on their electrical and optical performances; there have been numerous attempts to improve these properties, such as chemical doping and crystallinity enhancement. Recently, due to rapidly increasing demand for flexible electronics, the academic interest in the mechanical stability of materials has come to the fore as a major issue. In particular, long-term stability under bending is a crucial requirement for flexible electrodes; however, research on this feature is still in the nascent stage. Hydrogen-incorporated amorphous In-Sn-O (a-ITO) thin films were fabricated by introducing hydrogen gas during deposition. The hydrogen concentration in the film was determined by secondary ion mass spectrometry and was found to vary from $4.7{\times}10^{20}$ to $8.1{\times}10^{20}cm^{-3}$ with increasing $H_2$ flow rate. The mechanical stability of the a-ITO thin films dramatically improved because of hydrogen incorporation, without any observable degradation in their electrical or optical properties. With increasing hydrogen concentration, the compressive residual stress gradually decreased and the subgap absorption at around 3.1 eV was suppressed. Considering that the residual stress and subgap absorption mainly originated from defects, hydrogen may be a promising candidate for defect passivation in flexible electronics.

• 한국가스학회지
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• 제14권6호
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• pp.38-43
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• 2010

자원 부족과 환경규제의 강화에 따라 자동차 강판재의 고강도화와 박강판화가 주요 이슈로 대두되고 있다. 그러나 고강도 강판재 사용에 있어 수소취성은 기계적 성질 저하의 문제가 되고 있다. 본 연구에서는 개발중인 590MPa급 DP강을 대상으로 조성 및 조직특성에 따른 표면층에서의 수소의 거동에 대해 연구하였다. 수소주입은 음극전기분해법을 이용하여 강제 주입시켰고, 수소주입조건에 따른 수소주입량과 표면층 조직관찰 및 미소경도시험 결과의 관계로 부터 표면층의 수소거동을 평가하였다.

• 한국수소및신에너지학회논문집
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• 제31권4호
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• pp.337-344
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• 2020

Worldwide, there is a significant surge in the efforts for addressing the issue of global warming; the use of renewable energy is one of the solutions proposed to mitigate global warming. However, severe volatility is a critical disadvantage, and thus, power-to-gas technology is considered one of best solutions for energy storage. Hydrogen is a popular candidate from the perspective of both environment and economics. Accordingly, a hydrogen production system based on renewable energy sources is developed, and the economics of the system are assessed. The result of the base case shows that the unit cost of hydrogen production would be 6,415 won/kg H₂, with a hydrogen production plant based on a 100 MW akaline electrolyzer and 25% operation rate, considering renewable energy sources with no electricity cost payment. Sensitivity study results show that the range of hydrogen unit cost efficiency can be 2,293 to 6,984 Won/kg H₂, depending on the efficiency and unit cost of the electrolyzer. In case of electrolyzer operation rate and electricity unit cost, sensitivity study results show that hydrogen unit cost is in the range 934-26,180 won/kg H₂.

• 디지털정책학회지
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• 제1권2호
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• pp.47-52
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• 2022

드론 비행의 위치 인식에 있어 GPS 신호의 절대적 의존성, 비행 안정성, 배터리 한계로 인한 비행시간 문제는 드론 산업 발전의 큰 제약이 되고 있다. 특히 20분 내외의 짧은 임무 비행시간은 드론 활용에 있어 큰 걸림돌이 되고 있으며, 이를 극복하기 위해 액체수소를 에너지원으로 이용한 드론개발이 활발히 진행되고 있다. 하지만 액체수소 드론개발의 속도보다 현재의 규제 및 인증 제도 개정의 속도가 더뎌 개발 드론의 시험, 인증, 상용화에 어려움을 겪고 있으며, 이는 결국 드론 시장 선점의 문제점이 되고 있다. 본 논문에서는 수소 에너지 기반 드론개발 동향을 분석하며 규제와 인증 제도의 한계점을 소개하고 해결방안을 간략히 제시한다.

• 한국수소및신에너지학회논문집
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• 제13권1호
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• pp.3-12
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• 2002

In this study, it achieved life cycle assessment to estimate environmental performance for naphtha steam reforming that account for the production over 50% of total hydrogen output. Although hydrogen dosen't emit air emissions, especially, $CO_2$, a large of $CO_2$ is emitted in hydrogen production process. In the result of this study, it ascertained the truth that $CO_2$ is emitted at the rate of $6.3kg/kgH_2$ and that result from steam reforming reaction and use of fossil fuel in hydrogen manufacturing process. Above all, 57% of total $CO_2$ emissions is emitted in process of steam reforming of naphtha and so it knew that the principle of steam reforming is key issue in aspect to environment. Also, it compared hydrogen by fuel of fuel cell vehicle with gasoline fuel of general gasoline vehicle to analyze relative environment of hydrogen for fossil fuel during the life cycle. As the result, it might be difficult in improvement of environment because $CO_2$ emissions during the hydrogen manufacturing process is nearly the same with that during the use of gasoline.