• The Optical Journal
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• s.141
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• pp.46-50
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• 2012

플라즈마는 반도체, 우주 추진체, 수소 에너지, 디스플레이, 태양전지 등 다양한 산업 분야에서 활용되고 있다. 특히 대기압 플라즈마는 기압을 낮추기 위한 별도의 기압 조정 설비가 필요하지 않아 활용도가 매우 높다. 이번호에서는 최첨단의 대기압 플라즈마 장치인 '멀티가스 데미지프리 플라즈마 제트', '리니아형 데미지프리 플라즈마', '온도제어 플라즈마'를 소개한다. 이 원고는 도쿄공업대학 종합이공학연구과 창조에너지전공의 오키노 아키토시 교수가 월간 OPTRONICS 2012년 6월호에 기고한 내용으로 그린광학의 유정훈 팀장이 번역에 도움을 주었다.

• Journal of Hydrogen and New Energy
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• v.32 no.6
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• pp.565-572
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• 2021

Hydrogen is currently produced from natural gas reforming or industrial process of by-product over than 90%. Additionally, there are green hydrogens based on renewable energy generation, but the import of green hydrogen from other countries is being considered due to the output variability depending on the weather and climate. Due to low density of hydrogen, it is difficult to storage and import hydrogen of large capacity. For improving low density issue of hydrogen, the gaseous hydrogen is liquefied and stored in cryogenic tank. Density of hydrogen increase from 0.081 kg/m³ to 71 kg/m3 when gaseous hydrogen transfer to liquid hydrogen. Density of liquid hydrogen is higher about 800 times than gaseous. However, since density and boiling point of liquid hydrogen is too lower than liquefied natural gas approximately 1/6 and 90 K, to store liquid hydrogen for long-term is very difficult too. To overcome this weakness, this paper introduces storage method of hydrogen based on liquid/solid (slush) and facilities for producing slush hydrogen to improve low density issue of hydrogen. Slush hydrogen is higher density and heat capacity than liquid hydrogen, can be expected to improve these issues.

• Journal of Hydrogen and New Energy
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• v.33 no.5
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• pp.470-498
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• 2022

Recently, the world has been considering hydrogen energy as the primary energy transition means to achieve carbon neutrality by 2050. In order to achieve the goal of reducing greenhouse gas emissions, Korea is also promoting a clean hydrogen economy. However, it is necessary to introduce various clean hydrogen from overseas so that the projected demand can not meet the domestically produced. For this study, we conducted the policy comparison approach between countries other than the generally considered technical and economic approaches. The finding proposes the direction of bilateral cooperation for a strategy of securing overseas clean hydrogen from a geopolitical perspective. Germany was a target country for the policy comparison since it has a high proportion of manufacturing, like Korea, and is taking the lead in the renewable-based energy transition policy. According to the survey and analysis of the policy establishment status and new projects of the two countries, Germany is promoting bilateral international cooperation in the hydrogen area with about 33 countries based on 7 types of activities. In comparison, Korea is involved in bilateral cooperation with about 12 countries on relatively few activities. Among the types of bilateral cooperation, R&D cooperation with advanced countries for hydrogen technology was a common activity type. Germany preemptively promotes cooperation for demonstration and commercialization, considering geopolitical means and strengthening manpower training and assistance on policy and regulation to preoccupy the market for the future. Therefore, it is necessary to consider establishing a network of an entire life cycle of supply and demand network that links the future market with securing clean hydrogen considering the geopolitical distribution. To this end, Korea also needs to expand bilateral cooperation countries by activity type, and it seems necessary to seek various geopolitical-based bilateral cooperation and support measures for developing countries to diversify the supply sources of hydrogen.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.1
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• pp.47-58
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• 2014

In this research, the initial sizing of a HALE(High Altitude Long Endurance) UAV which uses solar power and hydrogen fuel cell as an alternative energy was performed. Instead of a wing box type, a glider type was chosen since it is relatively easy to get a data thanks to many researches abroad. Maximum takeoff weight is around 150Kg and the propulsion system is composed of motor, propeller, solar cell, and hydrogen fuel cell which can be recharged through electrolysis. Maximum takeoff weight was estimated as aspect ratio, wing span, wing area change while considering energy balance of required energy which is necessary for flight during the entire day and available energy which can be taken from the solar cell.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.2
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• pp.79-95
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• 2022

Since space exploration began in the 1950s, numerous upper stage engines have been developed and used based on various design concepts. In this paper, information of upper stage engines which developed or developing is analysed and their characteristics and performance are summarized. These days, there are many cases of commercial heavy launch vehicles applying upper stage engines using liquid hydrogen with expander cycle which launched recently. Engines operating by Kerosene seem to be close to its theoretical maximum performance based on past experiences. Meanwhile, engines using methane propellant, which has recently become an issue, are also undergoing many developments because of various advantages. Recently, private companies are actively participating in launch vehicle market, and there are many cases in which the government and companies jointly research of next-generation engine.

• Journal of Radiation Protection and Research
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• v.38 no.2
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• pp.124-131
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• 2013

Utilities have tried to ensure that radiological hazards to the environment and residents are kept as low as reasonably achievable by monitoring and controlling planned releases. However, since groundwater contamination was reported to occur due to unplanned releases mostly in the United States nuclear power plants, the interest of the stakeholders has increased to a point where it is now one of the most important issues in the United States nuclear power industry. This paper aims to help to implement an effective on-site groundwater monitoring program at domestic nuclear power plants by briefing the experiences of the United States nuclear power plants on groundwater contaminations and groundwater monitoring, and responses of the United States nuclear industry and regulator body for them.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.433-436
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• 2007

가스화기술은 화석연료에 의한 기존의 화력발전기술을 대체할 수 있는 차세대 발전기술로 여겨지고 있어 전 세계적으로 기술개발은 물론 상용 플랜트를 앞 다투어 도입 건설 중에 있다. 현재 국내에서도 2014년까지 실증플랜트 완공에 매진을 가하고 있는 실정이다. 가스화기술은 온실가스인 이산화탄소를 동시에 감축하면서 전력뿐만 아니라 수소, DME, 화학원료와 같은 2차 고급 에너지원을 생산할 수 있다는 장점을 가지고 있다. 이 연구에서는 ASPEN plus를 이용하여 다양한 원료 공급에 따른 300 MW급 IGCC 플랜트에 대한 운전 특성을 알아보고자 하였다. 가스화기에 공급되는 원료는 석탄(역청탄), 중질유(납사, 벙커C유) 등으로 구분해 고려하였으며, 가스화 플랜트 해석모델에 대한 성능을 평가하기 위하여 해외에서 운전 중인 상용 IGCC 플랜트에 대한 운전자료와 상대오차로 비교 산출해 검증하였다. 그 다음으로 가스화(gasification)공정, 산가스 제거(acid gas removal)공정, 복합발전 공정(combined cycle)등과 같은 IGCC 플랜트를 구성하고 있는 각각의 단위공정에 대한 운전 특성에 대한 해석결과를 확인하였다. 해석 결과를 바탕으로 가스화기의 냉가스 효율(cold gas efficiency)과 탄소 전환율(carbon conversion), 산가스 제거공정에 대한 이산화탄소 포획 성능과 복합발전에 따른 플랜트 발전량 및 발전 효율(plant net efficiency)을 예측하였다.

• Bulletin of the Korea Photovoltaic Society
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• v.4 no.3
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• pp.36-41
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• 2018

연일 뉴스에 보도되고 있는 미세먼지는 노약자의 호흡기는 물론 발암물질을 포함하고 있어 국민건강에 악영향을 미치기 때문에 반드시 해결되어야 할 사회 문제이다. 미세먼지는 해외 유입 인자와 국내 유발인자를 정확하게 구분하기 어려우나 약 50%의 미세먼지는 2차 발생에 의한 국내 요인으로 발생하고 있는 것으로 파악되고 있으며 화력발전소가 미세먼지 유발 물질의 주요 생성원으로 지목되어왔다. 국내 화력발전소의 50%가 충남 서해안이 위치하고 있어 수도권에 가장 큰 영향을 주는 것으로 밝혀져 충남은 내구연한에 도달한 노후 화력발전소의 폐쇄 및 발전량 감축 조절을 통해 미세먼지 발생을 최소화 하기 위해 노력해왔다. 그러나 태양전지 주도의 신재생에너지 발전으로 전환하는 것만이 미세먼지를 저감시킬 근본적인 해결책이라고 할 수 있다. 충남은 2050년까지 화력발전 비중을 0%로 낮추고 필요한 전력은 에너지컨슈머들이 생산하는 신재생에너지로 생산하는 내용을 골자로 하는 에너지 전환비전을 선포하였다. 이 비전이 선언에 그치지 않고 목표를 달성하기 위해서 이에 대한 세부 이행계획을 수립하고 충남에 맞는 태양광 발전 산업 육성을 위한 정책을 병행해야 할 것이다. 이번 글에서는 충남의 여건을 고려하여 태양광을 이용한 수소 생산 및 인공광합성을 연계한 고부가가치 화학물질의 생산 연구 및 실증 과제를 추진할 것을 제안하였다. 이러한 충남의 노력은 수도권 수요 지역에 대한 전력 공급기지에서 친환경에너지로 유지되는 '청정남도'로서의 재도약을 가능하게 할 것으로 기대된다.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.3
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• pp.81-124
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• 2020

In liquid oxygen/kerosene liquid rocket engines, kerosene is not only a propellant but also plays a role as a coolant to protect the combustion chamber wall from 3,000 K or more combustion gas. Since kerosene is exposed to high temperature passing through cooling channels, it may undergo heat-related chemical reactions leading to precipitation of carbon-rich solids. Such kerosene's thermal and fluidic characteristic test data are essential for the regeneratively cooled combustion chamber design. In this paper, we investigated foreign studies related to regenerative cooling channel and kerosene. Starting with general information on hydrocarbon fuels including kerosene, we attempted to systematically organize sedimentary phenomena on cooling channel walls, their causes/research results, coking test equipments/prevention methods, etc.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.496-504
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• 2023

Countries worldwide are striving to find new sources of sustainable energy without carbon emission due to the increasing impact of global warming. With the advancement of the fourth industrial revolution on a global scale, there has been a substantial rise in energy demand. Simultaneously, there is a growing emphasis on utilizing energy sources with minimal or zero carbon content to ensure a stable power supply while reducing greenhouse gas emissions. In this comprehensive overview, a comparative analysis of carbon reduction policies of government was conducted. Based on international carbon neutrality scenarios and the presence of remaining thermal power generation, it can be categorized into two types: "Rapid" and "Safety". For the domestic scenario, the projected power demand and current greenhouse gas emissions in alignment with "The 10th Basic Plan for Electricity Supply and Demand" was examined. Considering all these factors, an overview of the current status of carbon neutrality technologies by focusing on the energy sector, encompassing transitions, hydrogen, transportation and carbon capture, utilization, and storage (CCUS) was offered followed by summarization of key technological trends and government-driven policies. Furthermore, the central aspects of the domestic carbon reduction strategy were proposed by taking account of current mega trends in the energy sector which are highlighted in international scenario analyses.