• 한국전기전자재료학회논문지
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• 제24권1호
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• pp.57-63
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• 2011

Dielectric Barrier Discharge (DBD) reactor with sinsodual AC type of power supply is very widely adopted for its compact size and effective discharging mechanism to generate high density of ozone radicals. However, at the aspect of design on power supply, its optimal switching conditions and topology is achieved by empirical test. Therefore, throughout this paper, it is proposed a design method of DBD power supply to guarantee a maximum ozone yield rate in accordance with DBD reactor modification and impedance variation when rapid gas discharging in the DBD reactor is proceeded.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 전력전자학술대회
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• pp.45-47
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• 2018

This paper describes the 40kV solid state pulsed power supply for environmental applications. The output specifications of the pulsed power supply are 40kV, 300A, 3kHz, and average output power of 13kW. In order to generate a high voltage, a series stacking cell structure is used which is charged in parallel and discharged in series. Due to this structure, there is no dynamic voltage balancing problem as well as static voltage balancing problem for switches used in high voltage pulse power supplies. To verify this pulse power supply design, PSpice modeling was performed. Finally, experimental results with non-inductive resistive load and gas treatment reactor proved the reliability of the solid state pulsed power supply.

• Advances in Energy Research
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• 제2권2호
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• pp.61-72
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• 2014

This paper's aim is to do a global evaluation (considering four dimensions: technical-economic, environmental, social and political) in the ways of natural gas transportation (gas pipelines, GNL and GTL) and electric transmission, in order to supply the energy demands of Mato Grosso do Sul, a brazilian state. The transport ways had been compared between itself using a software of decision taking (Decision Lens Suite), which determined a better way for transporting natural gas in this case. In a generalized manner the gas pipeline is the best way of transporting natural gas, therefore it takes advantage in the majority of the analyzed dimensions.

• 전기학회논문지
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• 제57권10호
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• pp.1720-1725
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• 2008

Because of the continuous increasing of energy consumption, metallic pipelines are widely used to supply services to customers such as gas, oil, water, etc. Most common metallic pipelines are underground and are now frequently being installed in nearby electric power lines. In recent years, buried gas pipeline close to power lines can be subjected to hazardous induction effects, especially during single line to ground faults. because it can cause corrosion and it poses a threat to the safety of workers responsible for maintenance. Accordingly, it is necessary to take into consideration for analysis of induced voltage on gas pipelines in transmission lines. This paper analyzed the induced voltage on the gas pipelines due to the 154kV transmission lines in normal case and in different faulty case conditions using EMTP (Electro-Magnetic Transients Program).

• 한국분말재료학회지
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• 제24권5호
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• pp.351-356
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• 2017

Tin dioxide nanoparticles are prepared using a newly developed synthesis method of plasma-assisted electrolysis. A high voltage is applied to the tin metal plate to apply a high pressure and temperature to the synthesized oxide layer on the metal surface, producing nanoparticles in a low concentration of sulfuric acid. The particle size, morphology, and size distribution is controlled by the concentration of electrolytes and frequency of the power supply. The as-prepared powder of tin dioxide nanoparticles is used to fabricate a gas sensor to investigate the potential application. The particle-based gas sensor exhibits a short response and recovery time. There is sensitivity to the reduction gas for the gas flowing at rates of 50, 250, and 500 ppm of $H_2S$ gas.

• 자원ㆍ환경경제연구
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• 제11권4호
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• pp.633-657
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• 2002

This study presents a demand modelling for landfill gas, which is used as alternative energy source for district cooling business. By analyzing the cost minimizing behavior of producer facing with three alternative energy sources such as electricity, cooling heat water, and gas, a demand function for landfill gas is derived from the optimal operating time of gas fired production facility, and estimated using unpublished data, which are associated with Seoul city's development plan for Sang-am area. The estimation results repeals that Seoul City could supply the land-fill gas of 13.76 million cubic meters each year at the price of about 16 won per cubic meters. However, if the investment costs associated with installation of gas collecting facilities are treated as sunk costs, annual amount of gas supplied is expected to increase to 14.22 million cubic meters at a lower unit price of 14.76 won.

• 대한안전경영과학회지
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• 제17권3호
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• pp.331-341
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• 2015

Gasoline prices vary across Korea. Some gas stations charge higher prices, while others charge lower prices. In this paper, we try to find: why gasoline prices differ markedly across regions. We empirically estimate the determinants of gas prices by incorporating supply side factors as well as demand side factors into the empirical model. Empirical results show that both location-specific factors and store-specific factors affect gas prices. Concentration of competing stores, store brands, ownership of gas stations, and self-service availability influence gas prices. In addition, the availability of other customer services such as convenience stores, car wash, and auto repairs affects gas prices.

• 한국가스학회지
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• 제23권5호
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• pp.8-14
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• 2019

국내 도시가스 보급률은 크게 성장했지만, 국내 가스계량기 계량·안전점검·요금 분야는 아직 서비스 초기방식에서 벗어나지 못하고 있다. 스마트가스미터에 관한 개발과 연구가 활발히 이루어지고 있지만 스마트가스미터의 도입에는 신뢰성과 안전성을 검증할 수 있는 합리적인 성능평가 방안과 기준이 필요하다. 본 논문은 스마트가스미터의 성능을 시험하기 위한 성능시험 시작품을 제작하고 시작품의 실증 운용을 통해 성능평가 방안을 최적화하여 국내에 스마트가스미터가 원활하게 확대/보급될 수 있도록 하는 것을 목적으로 한다.

• 한국주거학회논문집
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• 제12권3호
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• pp.141-148
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• 2001

To design mechanical ventilation for bathroom of apartment houses where air supply and exhaust are taken into consideration, mock-ups of ventilation systems, widely used in bathroom of apartment houses with an area of 100$\textrm{m}^2$, were made and installed in a laboratory. These ventilation mock-ups were available for control of air supply and exhaust, and the sizes of supply openings were 40cm${\times}$1cm, 40cm${\times}$3cm, and 40cm${\times}$5cm. They were installed at five positions, spaced 45cm at a height of 5cm from the floor. The exhaust fan was designed for its operating voltage to be set to five steps(100V, 130V, 150V, 180V and 220V) in order to control its air flow rates. When the size and position of each supply opening were changed with the wind velocity of the exhaust fan set to the step 5, the ventilation rates were measured and analyzed by the concentration decay method of tracer gas method, in order to present an efficient mechanical ventilation system. The results of the study revealed that the ventilations rates would increase in the presence of supply openings, compared to the absence of supply openings, and that the larger the size of the supply opening, the more the ventilation rates. Therefore, it was found necessary to take air supply into consideration.

• 한국가스학회지
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• 제15권6호
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• pp.1-7
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• 2011

도시가스 공급시설에서 위험인자의 계측은 근래까지 인력에 의하여 측정 및 확인되었으며 유선통신을 이용하여 원격모니터링 시스템으로 진화해왔다. 더 나아가 국내/외 산업시설은 무선통신 기반 원격 모니터링 시스템 및 제어 시스템을 개발하여 관리의 효율성을 향상시켜왔다. 그러나 외부에서 데이터를 확인이 즉각적으로 확인하기 위해서는 유선으로 PDA나 노트북에 연결함으로써 효율성과 편의성이 감소되기 때문에 본 논문은 증강현실 기반 모바일 도시가스 안전관리 시스템을 개발하여 도시가스 공급시설의 안전관리 효율성을 개선하고자 한다.