• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.729-732
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• 2008

최근 실내공기질에 대한 관심이 집중되고 있는 가운데 이를 개선하고자 하는 노력이 다각도로 진행되고 있다. 본 연구는 기존의 친환경 마감재 적용 기술과 달리 콘크리트 자체에 활성탄과 흡착된 오염 공기를 분해할 수 있도록 기능성 촉매를 혼입함으로써 기본적인 물성과 포름알데히드 제거율을 시험하여 공기정화 효과를 분석하고자 하였다. 실험 결과 활성탄의 첨가량 증가에 따라 슬럼프는 감소하는 경향을 나타내었고, 압축강도는 큰 차이 없이 유사한 것으로 나타났다. 공기질 개선과 관련하여 포름알데히드 제거율을 시험한 결과 최대 80%까지 제거하는 것으로 나타났다.

• 항공우주정책ㆍ법학회지
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• 제26권1호
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• pp.127-145
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• 2011

European Union unilaterally included the emissions from aviation activities into EU ETS on 19 November 2008 by amending Directive 2003/87/EC. According to the Directive all the emissions(mainly against the CO2) from aviation activities shall be subject to the regulation of EU ETS from 2012. For the period from 1 January 2012 to 31 December 2012, the total quantity of allowances to be allocated to aircraft operators shall be equivalent to 97% of the historical aviation emission s. From 1 January 2013, the allowances will be reduced to 95%. The allocation of allowances which may be applied by each operator with free of charge will be reduced from 85% to 82% from 1 January 2012 to 1 January 2013. Since the Directive will affect every country's airline industry more or less, the nations and international organizations respond variously. The controversial focus is that whether EU has the right to unilaterally include the emissions from international aviation activities into EU ETS. This article firstly analyzes the effect caused by EU ETS to China's airline industry, and then studies the legality of the action of EU subject to current positive international law, and finally draws the conclusion that EU enjoys no such right to unilaterally include the emissions from international aviation activities.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 춘계 학술대회논문집
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• pp.71-78
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• 2002

All modem, aerospace gas turbines must operate with hot stage gas temperature several hundreds of degrees hotter than the melting temperatures of the materials used in their construction. Complicated cooling schemes need to be employed in the combustor walls and In the high pressure turbine stages. Internal passages are cast or machined into the hot sections of aero-gas turbine engines and air from the compressor is used for cooling. In many cases, the cooling system is engineered to utilize jets of high velocity air, which impinge on the internal surfaces of the components. They are divided by Impinging cooling method and Vortex cooling method. Specially, Research of new cooling system(Vortex cooling method) that overcome inefficiency of film cooling and limitation of space. The focus of new cooling system that improve greatly cooling efficiency using quantity's cooling air which is less is set in surface heat transfer elevation. Therefore, In this study, the numerical analysis have been performed for characteristic of flow and thermal in the swirl chamber and compared with the flow field measurement by LDV. especially, for understanding of high heat transfer efficiency in vicinity of wall. we considered flow structure and mechanism of vortex and heat transfer characteristic in variation of Reynolds number.

• 상하수도학회지
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• 제13권3호
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• pp.61-72
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• 1999

To obtain the experimental data for design and operation of actual filtration processes, a sand filter and three kinds of dual media filters in pilot-plant scale were operated in this study. We analyzed the effect of filter medium composition on the filter performance and the effects of backwash water flow rates, length of stream line and air flow rate on the filter backwash efficiency. We also compared the efficiencies of the combined air-water backwashing and the water backwashing in dual media filters. As the backwash water flow rates or the length of stream line increased, the final turbidity of backwash water was decreased and the filtration duration time after backwash was increased. In the case of the combined air-water backwashing, the backwash water quantity needed for backwashing the dual media filters could be decreased. The total volume of filtered water for the dual media filters during filter run was over three times larger than that for the sand filter. The dual media filters could be operated at a high filtration rate of 360 m/day.

• 한국측량학회지
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• 제17권3호
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• pp.273-282
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• 1999

대기환경분야에 GSIS를 활용하기 위해서는 우선적으로 이러한 연속면적 성질을 지닌 대기오염이나 기후인 자를 비롯한 연속면(continuous surface)의 특성을 가진 환경인자의 공간분포를 도면화 할 수 있어야 한다. 이를 위해서는 몇몇의 한정된 지점에서 측정된 점관측(point observation)자료에 의존하여 전 지역의 분포를 추정해야 한다. 본 연구에서는 자동차에 의한 대기오염물질 발생현황을 실질적으로 파악하기 위한 조사ㆍ연구의 일환으로 서울시 전지역을 대상으로 실시한 서울시 교통센서스의 자동차 통행량 자료, 오염물질별 배출계수 및 GIS-T용 수치지도등의 자료들을 이용하여 오염물질 배출특성을 지역별, 항목별, 시간별로 가시화 할 수 있는 GSIS기법의 적용성을 검토하고자 하였다.

• 한국환경생태학회지
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• 제7권2호
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• pp.252-269
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• 1994

본 연구는 산성비 및 대기오염물질이 수도권지역의 침엽수 잎에 미치는 피해의 조기판단을 위해 피해도지수, 침엽접촉각, 엽내영양물질, 침엽내 wax, 토양의 화학적 성질 등의 항목을 조사.분석하였다. 조사기간은 1990년 6월부터 1년 동안 하였고, 재료는 대기오염에 민감한 수종으로 알려진 독일가문비나무와 전나무를 이용하였으며 연구결과는 다음과 같다. 피해도지수는 1990년 6월에는 무피해지(광릉, 양평), 경피해지(인천, 보라매공원, 서울여대, 안양, 양수리, 과천), 심피해지(남산, 서울시립대, 어린이대공원, 금곡릉)으로 나누어졌다. 그러나, 1990년 12월에는 인천, 과천이 심피해지로 포함되는 등 시간이 경과할수록 피해가 확산되는 경향을 보였다. 침엽의 접촉각에서도 1990년 6월보다 1990년 12월의 값이 감소하였으며, 두수종 모두 1년생잎에서 2, 3년생잎으로 갈수록 접촉각이 낮게 측정되었다. 그리고, 어린묘목일수록 피해가 심하게 나타났다. 피해도지수와 접촉각간에는 고도의 상관관계가 인정되었다. 엽내영양물질분석에서 Ca, Mg, K의 값은 대체로 시간경과에 따라 감소하였으며, 엽령이 높을수록 낮은 값을 보였다. Wax정량분석은 심피해지역에서는 엽령이 높을수록 wax함량이 적었고, 무피해지역에서는 엽령이 높을수록 많았다. 본 연구결과에 의하면 위 항목의 분석방법들이 상호보완적으로 적용되고, 장기간 지속적으로 수행될 경우 보다 좋은 결과를 얻을 수 있을 것이라 판단되었다.

• 한국기계기술학회지
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• 제20권6호
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• pp.763-769
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• 2018

In this research, in order to improve the heat retention of greenhouse, comparative analysis of the heat flux of the marketed multi-later insulating curtain was carried out. Experiments is conducted by fabricating a test apparatus for investigating the heat flux characteristics. The multi-later insulating curtain used for the experiment was compared using the P, N, S, U and T company, which are commercially available, and the heat flux due to temperature difference between the experimental apparatus and the outside was compared and analyzed. When the internal temperature of the experimental result is the maximum temperature $60^{\circ}C$, the heat flux of multi-later insulating curtain is T Co.($73.1W/m^2$) > S Co.($119.5W/m^2$) > U Co.($155W/m^2$) > N Co.($163.1W/m^2$) > P Co.($177.7W/m^2$). The heat flux means the quantity of heat passing through the unit time per unit area, and the higher the numerical value, the higher the quantity of heat passing through the multi-layer insulating curtain. This can be determined that high heat fluxes produce low heat resistance. Further, it has been found that the weight of the insulating curtain is largely unrelated to the heat insulating property, and the heat insulating curtain having a thickness containing a high internal air layer is excellent in the heat insulating property. In the future when manufacturing a heat insulating curtain, It is judged that it is desirable to manufacture a combination of heat insulating materials that contain a high internal air layer content and that can maintain the air layer even for long-term use while minimizing the volume.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
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• pp.448-451
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• 2005

교통의 혼잡량이라든가 공기의 쾌적도 둥을 측정할 때는 상징적인 정보량을 이용한 퍼지 센서 알고리즘을 사용한다. 그런데 퍼지 센서를 구현할 때는 몇 개의 상징적인 정보량을 퍼지 규칙으로서 종합하여 출력을 산출하는데 상징적인 정보량을 퍼지 규칙이라는 막연한 방법을 사용하므로서 정확하지 못한 결과를 산출할 수밖에 없다. 따라서 본 논문에서는 퍼지 규칙으로 퍼지 센서를 구현하는 방법이 아닌 계층 분석 방법이라는 분석적인 방법을 이용하여 퍼지 센서를 구현하였고 이를 검증하기 위하여 퍼지 규칙 방법의 괴지 센서와 계층 분석 방법의 퍼지 센서를 교통량 제어에 적용하여 많은 통과차량수의 검증을 통하여 비교하여 보았다.

• 한국생산제조학회지
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• 제8권2호
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• pp.94-94
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• 1999

Natural gas is considered to be on e of the most promising candidates for a clean substitute fuel and a great amount of research on the compressed natural gas(CNG) fueled vehicle has been performed. In this s tudy, we try to understand the property of CNG fuel with using CNG engine experiment. In order to present the direction and application of CNG, we experiment with various operating conditions that is, spark timing, A/F ratio, air quantity and fuel quantity, etc. 11,967 cc engine was used in the experiment and the engine fuel ratio was determined in the way that the performance of dedicated CNG engine is corresponded to that of existing diesel engine. The performance and dedicated CNG engine were measured by changing the fuel injection timing. The dedicated CNG engine was proved to be good in describing the experimental results and according to the actual road test, acceleration and constant speed driving for dedicated CNG engine was better than existing diesel engine.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.725-730
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• 2008

In this study, we found out charged particle's deposition characteristic by experiments of $0.5{\mu}m$, $1.0{\mu}m$, $3.0{\mu}m$ size particle's concentration decay. We carried out the experiments on charged particle deposition onto the vertical cleanroom wall panel and some other fundamental experiments. The particle deposition mechanism is consist of sedimentation, convection, diffusion, thermophoresis, electrostatic and so on. Particle size determines mainly working deposition mechanism. The charged particle is made with corona discharge that are constituted field charging and diffusion charging. In addition, this combinational mechanism is called combined charging. The type of corona discharge determines quantity of particle electrical charge. In conclusion, we assumed that quantity of particle electrical charge accelerations deposition velocity onto the vertical cleanroom wall panel and proved it. And we figured out particle's deposition characteristic through compared between our experiment's results.