• 전기학회논문지
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• 제60권8호
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• pp.1560-1565
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• 2011

The environmental pollution caused by green-house gases such as $CO_2$ and $SF_6$ has been becoming the main issue of industrial society. Many developed countries are making efforts to minimize the amount of $CO_2$ emission come from the operation of high voltage electrical apparatuses. As a part of these efforts, 180 countries signed the Kyoto Protocol in 1997 to cut back on their green-house gas emissions. Nowadays, the study on the development of dry air insulated switchgear (DAIS) which is known as an eco-friendly electrical apparatus is in progress. A DAIS is advantageous for minimizing the effect of impurities and enhancing the dielectric characteristics over an air insulated switchgear (AIS) by applying constant pressure to an enclosed cubicle. Therefore, a study on the electrical insulation performance of dry air as a gaseous insulation medium is conducted in this paper to substitute a gas insulated switchgear (GIS) for DAIS. As results, it is verified that the AC dielectric characteristics of dry air are similar to those of air and the lightning impulse dielectric characteristics of dry air are superior to those of air at 1bar pressure condition. However, dry air is of inferior dielectric characteristics to $SF_6$ at 4bar pressure condition. Finally, it is suggested that the internal pressure of DAIS should be over 4bar pressure to develop a high voltage switchgear which has similar electrical performance to a conventional GIS. Also, the empirical formulae on calculating the maximum electric field intensity at sparkover of dry air are deduced by experiments according to pressures. It is expected that these results are helpful to design and develop a high voltage electrical apparatus.

• 한국항공운항학회지
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• 제24권1호
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• pp.47-54
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• 2016

Global aviation is projected to grow in demand by an annual average of 4.1% between 2014 and 2034. It can be said that environmental impact from aviation will therefore be expected to increase on a similar scale. As regards civil aviation emissions, the sector contributes between 2~3% to International aviation GHG emissions. In the European Union(EU), aviation emissions account for about 3% of the EU's total green house gas emissions, of which a majority are said to come from international flights. In terms of traffic volume in 2013, Korea's international aviation industry 11th with regard to passengers and 3rd with regard to cargo, attaining the overall rank of 5th in the world. GHG emissions has been increasing steadily over the last 4 years, averaging 3.9 percent a year, due to the growth of low cost carriers and the increased demand for air transportations. As for aviation in Korea, there are a number of means intended to attain the Government's emission control objective in an efficient manner, such as AVA (Agreement of Voluntary Activity), TMS (Target Management System) and ETS (Emission Trading Scheme). In addition, the Government intends to better adapt to ICAO's Global MBM(Market-based Measures) that will come into performance on Year 2020. In the study, we focused on GHG mitigation measures that is fulfilling the AVA, TMS, ETS in the Government and suggest the effective measures to reduction the aviation GHG emissions.

• 한국분무공학회지
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• 제19권3호
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• pp.115-122
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• 2014

As a demand for an automobile increases, air pollution and a problem of the energy resources come to the fore in the world. Consequently, governments of every country established ordinances for green-house gas reduction and improvement of air pollution problem. Especially, as international oil price increases, engine using clean energy are being developed competitively with alternative transportation energy sources development policy as the center. Bio ethanol, one of the renewable energy produced from biomass, gained spotlight for transportation energy sources. Studies are in progress to improve fuel supply methods and combustion methods which are key features, one of the engine technologies. DI(Direct Injection), which can reduce fuel consumption rate by injecting fuel directly into the cylinder, is being studied for Green-house gas reduction and fuel economy enhancement at SI(Spark Ignition). GDI(Galoine Direct Injection) has an advantage to meet the regulations for fuel efficiency and $CO_2$ emissions. However it produces increased number of ultrafine particles, that yet received attention in the existing port-injection system, and NOX. As fuel is injected into the cylinder with high-pressure, a proper injection strategy is required by characteristics of a fuel. Especially, when alcohol type fuel is considered. In this study, we tried to get a base data bio-ethanol mixture in GDI, and combustion for optimization. We set fuel mixture rate and fuel injection pressure as parameters and took a picture with a high speed camera after gasoline-ethanol mixture fuel was injected into a constant volume combustion chamber. We figured out spraying characteristic according to parameters. Also, we determine combustion characteristics by measuring emissions and analyzing combustion.

• 한국건설관리학회논문집
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• 제11권4호
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• pp.32-40
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• 2010

기후변화협약에 따라 선진국을 중심으로 한 세계 30여 개국이 현재 온실가스 의무감축 대상국으로 지정되어있다. 우리나라도 2013 년부터 시작되는 2차 의무감축에 의해 의무감축 대상국에 지정될 가능성이 높다. 이에 최근 정부는 온실가스 저감을 위한 노력이 이루어지고 있으며 온실가스 저감 대책으로 건축물 에너지를 감소하는 것과 관련된 정책을 시행하고 있다. 그러나 국내의 관련 정책은 에너지 절감과 관련된 측면에 있어 해외 사례에 비하여 건축물 개선안 제공 및 건물 개보수시 전문가 검증과 같은 절차가 없다. 이에 따라 이러한 문제점을 보완하는 국내 정책의 개선방안이 정부 단위, 시도 단위의 정책을 기준으로 제시되었다. 하지만 본 연구에서 제시한 개선방안은 개략적인 개선방향으로 세부적인 내용은 향후 추가적인 연구가 필요할 것으로 판단된다.

• 농업과학연구
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• 제35권1호
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• pp.69-83
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• 2008

The self-supply rate of Korea in 2006 was approximately 27.3 % by importing 13.99Mt for 19.79Mt of demanded amount. Among the imported crops, wheat, corn, and soybean consumed 95 % for the total imported amount, and wheat, corn, and soybean were 3.5Mt(Table use : 0.22Mt; Feed stuff : 0.13Mt), 8.7Mt(Table use : 0.19Mt; Feed stuff : 0.68Mt), and 1.2Mt (Table use : 0.03Mt; Feed stuff : 0.09Mt), respectively. On the other hand, our government has prepared the strategies for a great fear of food according to sharp price rise of the international crops by maintaining the self-supply rate of 5 % excluding 5.23Mt of rice in Korea. Also concern for recycled energy known as future energy for era of high oil price and global warming due to green house gas is rapidly growing. Therefore, our country which has relied on import of the whole oil needed in Korea and has to keep Kyoto Agent to request reduction of green house gas fully support research and practical use for agricultural products as resource of alternate energy. At first, we have to develop the mass production technology in order to secure a program of self-supply of food for bioenergy production utilizing agricultural product in Korea. But we assume that this matter is difficult to achieve under the current agriculture system that more emphasizes the environment conservation such as environmentally-friendly agriculture than production of food.

• 전기학회논문지P
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• 제63권4호
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• pp.356-360
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• 2014

The environmental pollution caused by green-house gases such as $SF_2$ has been becoming the main issue of industrial society. As a part of these efforts, 180 countries signed the Kyoto Protocol in 1997 to cut back on their green-house gas emissions [1]. Therefore, a study on the dielectric characteristics of the $GN_2$ is important for designing a eco-friendly high voltage apparatuses. In this paper, to develop an electrically reliable, stable, and eco-friendly high voltage apparatus, the breakdown voltage and partial discharge inception voltage characteristics in $GN_2$ considering utilization factors are studied for the establishment of insulation design criteria of an high voltage apparatus. Dielectric experiments are performed by using several kinds of sphere-plane electrode systems made of stainless steel. Also, the dielectric characteristics of the $GN_2$ are analyzed by using a Finite Elements Method (FEM) according to various field utilization factors. The results are expected to be applicable to designing the high voltage apparatuses using $GN_2$ as an insulation gas.

• 한국항해항만학회지
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• 제35권5호
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• pp.371-380
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• 2011

교토의정서에서 국제항해 선박의 온실가스 배출규제문제를 IMO에 위임하여 현재 IMO MEPC에서 논의중에 있다. 유엔해양법협약에 따라 모든 국가들은 해양환경보호를 위한 동등한 의무와 책임을 부담하여야 하며, 항만국은 입항하는 외국적 선박을 비차별적 원칙에 따라 통제하도록 하고 있다. 그러나 교토의정서의 기본협약인 기후변화협약은 온실가스 배출의 역사적 책임을 일부 선진국에 부과하는 차별적 공동책임을 기본원칙으로 내세우고 있기 때문에 IMO가 마련하고 있는 선박기인 온실가스 배출규제의 동등한 의무와 책임 원칙과 상반되는 양상을 보이고 있다. 따라서 이 논문에서는 기후변화협약의 발전과정과 기본원칙을 살펴보고 IMO의 선박기인 온실가스 배출규제 최근동향을 통하여 유엔해양법협약과 IMO의 규제에 있어 국제법상 제기될 수 있는 문제점을 검토하여 선박기인 온실가스 규제를 유엔해양법협약과 IMO 협약의 원칙에 따라 현실적으로 구현할 수 있는 이론적 기초와 함께 이행수단을 제공하고자 한다.

• 자원리싸이클링
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• 제20권2호
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• pp.3-15
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• 2011

현재 CDM사업 등록은 대부분 에너지, 화학공정, 제조공정 분야에서 이루어지고 있다. 그러나, 무기질 자원재활용을 통한 CDM사업 등록은 그렇게 많지 않은 실정이다. 본 논문에서는 국내 무기질 폐기물의 재자원화를 통한 CDM사업 등록 가능성을 알아보기 위하여 국내외 CDM사업 현황 분석 및 적용사례를 조사하였다. 조사결과 CDM사업 등록 사례는 대량으로 활용할 수 있는 산업 중의 하나인 시멘트산업의 원료 대체화 분야에서 다수의 등록이 이루어진 것으로 조사되었다. 우리나라에서의 CDM사업 적용 전망은 산업의 규모, 무기질 자원 활용 산업 및 온실가스 배출량을 분석하고 대량으로 활용할 수 있을 정도로 지속적으로 발생되는 우기질 폐가물의 현황 등을 면밀히 검토해야 할 것으로 판단된다.

• Journal of Advanced Marine Engineering and Technology
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• 제36권2호
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• pp.230-237
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• 2012

최근 엔진 메이커들은 원유가 인상 및 대기환경 규제에 대응하기 위하여 디젤엔진의 대안으로서 가스엔진 개발에 대한 관심이 증가되고 있다. 이에 STX는 22HLX 디젤엔진을 기초로 한 1.6MW급 가스엔진을 개발하였다. 예연소실 방식의 개발된 가스엔진은 엔진속도가 1000rpm에서 제동평균유효압력이 21bar이고 질소산화물 배출량이 50ppm(공기 중 산소함유 15% 기준)의 우수한 성능을 가진다. 특히 열효율 45%의 우수한 연료 경제성을 가지며 이산화탄소 배출량은 디젤엔진의 약 75%수준으로 온실가스 저감에도 효과적이다.

• 한국수소및신에너지학회논문집
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• 제30권6호
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• pp.485-489
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• 2019

Hydrogen is known to be a clean fuel which does not generate a green house gas during the combustion. However, about 8 kg of carbon dioxide is generated during the course of producing 1 kg of hydrogen through reforming, water gas shift reaction and pressure swing adsorption in order to obtain a high purity hydrogen over 99.999% by volume. In this work, carbon dioxide generation is estimated according to four kinds of natural gas compositions supplied by Korea Gas Corporation and regarding natural gas as pure methane. For the simulation of the modeling, PRO/II with PROVISION V10.2 at AVEVA was utilized and Peng-Robinson equation of state with Twu's alpha function was selected.