• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.257-262
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• 2011

A low capacity generator converted to high capacity of 40m3 is designed and developed in order to use the hydroxy gas in the steel manufacturing process. For efficient design, it is increased from 8 electrode tubes to 10 electrode tubes as well as expanding the diameter of cell integument up to two times bigger, which can increase the amount of hydrogen occurrence per a cell significantly. In addition, circulating pump and pipe, heat exchanger of affiliated SUS material have been used in the circulation of electrolysis catalyst, and circulating cooling section and piping design are also developed. The flame trap is designed into all-in-one suitable check valve in the flow rate of 28-35m3/h and its application is possibly applied in work operation. It is found that the efficiency of generator developed is enhanced substantially up to 84%. It is expected that the application in this field can be expanded significantly by this study.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.4
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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.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.4
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• pp.407-411
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• 2011

The technology of line heating has evolved in various methods. Among them, fossil fuels like ethylene gas and LPG(Liquid Petroleum Gas) are widely used due to their simple utility. In the meantime, the technology implementing high frequency for line heating has also been developed continually, but its manufacturing technology or application includes lots of problems by now. One of the main characteristics of line heating using conventional technolob'Y is the quenching effect followed by heating process. On the other hand, hydrox gas which is mixed by hydrogen and oxygen is a prominent candidate for an application without above shortcomings. Especially, it is found that line heating using hydrox gas is tremendously effective taking low cost as well as low noise. In this paper, a small cell with high efficiency which can minimize installing space is developed to deal with the problem installing in narrow place. Experiments to prove the validation, efficiency and effectiveness is carried out by characterizing in the line heating of steel. It is found that the energy saving of using hydrox gas for line heating is significant and that the deviation performance is reduced by 78~89%. Furthermore, the noise is also reduced as amount of 18.3% though the heating time is not too different.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2160-2162
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• 2001

화력 발전소의 주 연료로 사용되는 석탄은 1차 공기에 의해 노내로 이송되어 연소되게 된다. 연소에 필요한 1차 공기량은 연소되는 탄의 종류와 급탄기로 보내는 급탄량에 의해 결정되고, 1차 공기량 제어는 연소에 영향을 주며, 역화와 과열 방지를 위해 적절한 제어가 요구된다. 특히 단일 탄종이 아닌 여러 탄종을 연소하는 화력 발전소에서는 탄종에 따라서 그리고 연소되는 탄량에 따라서 미분기로 들어가는 1차 공기량을 변화시켜야만 한다. 본 논문에서는 2종류의 탄을 연소하는 발전소에 대해 연소탄종에 따른 1차 공기량 제어 로직을 구현하고, 구현한 로직에 의한 1차 공기량 제어 결과를 통해 구현한 제어 로직의 효용성을 보인다.

• Journal of the Korean Institute of Gas
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• v.16 no.4
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• pp.52-58
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• 2012

Recently, waste gas incineration is increasing due to strong environmental regulatory system in Korea. These incinerating facilities are usually connected with the top of the storage tank through pipeline and incinerate off gas with the flame. Therefore, the flame originated from these facilities is likely to move back into pipeline and might cause an explosion of the storage tank. Accordingly, the purpose of this study is to suggest the preventive measures and the way to improve the safety of these incineration systems through the cause analysis of a major industrial accident occurred in a acrylic acid manufacturing process in Korea. As a result of the study, the preventive measures are suggested as follows. (1) Air or inert gas inflow facilities should be well designed to dilute flammable gases into air or inert gas sufficiently before the blower is restarted in order to prevent the explosion (2) It is needed for the detonation-type flame arresters to be installed on the top of the storage tanks. (3) In case of using the deflagration-type flame arresters, it is necessary to install a rupture disk before the arresters, or blow off the flame outside tanks by connecting the tank top and the incinerator with hood-type pipe. (4) TDR should be installed to be restarted automatically after the momentary power failure.

• Information and Communications Magazine
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• v.30 no.6
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• pp.3-12
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• 2013

와이파이(Wi-Fi) 기술은 무선 데이터 트래픽 폭증에 따라 사업자에게는 트래픽 우회, 이용자에게는 통신요금 부담 완화의 대안으로 중요성이 부각되고 있다. 이에 우리나라에서는 이동 통신사업자 중심으로 와이파이를 지속적으로 확충하여 세계에서 가장 많은 와이파이 존(zone)을 보유한 국가가 되었다. 그러나, 특정 장소에 와이파이를 중복적으로 구축함에 따라 투자 효율성과 서비스 품질이 저하되고, 서민 소외계층 이용시설에는 구축이 상대적으로 저조하다는 문제점도 상존하는 상황이다. 본 고에서는 우리나라의 와이파이를 효율적으로 확산하고자 3가지 개선방향을 제시하였다. 첫 번째는 경쟁구축 차별화에서 투자효율화 공동이용 전략으로의 전환이며, 두 번째는 수도권 도시 지역 중심에서 서민 소외계층 지역으로 확산시키는 것이다. 마지막으로 Legacy Wi-Fi에서 차세대 Wi-Fi로 전환하는 것을 주요 방향으로 제시하였고, 이러한 개선방향을 바탕으로 4가지 전략을 제시하였다. 첫 번째 전략은 PPP(Public Private Partnership) 방식의 공공와이파이(Public Wi-Fi) 구축으로, 전통시장, 복지시설 등 서민 소외계층이 주로 이용하며 와이파이 구축이 열악한 이용시설에 정부, 지자체, 통신사가 공동으로 투자하여 공공와이파이를 구축함으로써 정보격차를 해소시키는 것이다. 두 번째 전략은 통신사의 와이파이 개방을 통한 공용화로, 통신사가 공공장소에 기 구축한 와이파이의 개방을 유도함으로써 중복투자 및 서비스 품질 저하 방지 등 공용화를 통한 투자효율성을 제고하는 것이다. 세 번째 전략은 차세대 와이파이 선도도입을 통한 글로벌 경쟁력 강화로, LTE 등 이동통신 기술의 급속한 보급에 맞추어 무선랜 서비스의 경쟁력 확보를 위해 광대역화 광역화를 선도하고, 응용서비스 발굴 및 산업활성화를 유도하는 것이다. 마지막은 공공와이파이 인식제고로, 공공와이파이의 이용편의성과 홍보활동을 강화하는 것이다. 이러한 전략의 핵심은 공공와이파이 확산과 차세대 와이파이 선도 도입으로, 이를 통하여 통신복지를 실현하고, 산업활성화를 통한 국민행복을 실현시키는 것에 대하여 간략히 설명한다.