• Clean Technology
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• v.18 no.1
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• pp.14-21
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• 2012

The pros and cons of green building thermal insulation materials and systems have been reviewed from traditional thermal insulation materials such as mineral wool and polyurethane to new thermal insulation materials like VIP and aerogel and future insulating VIM and DIM. VIPs and aerogels with very low thermal conductivity can use for green buildings to significantly increase residential area by reducing energy consumption. Aerogels can be produced as not only opaque and but also translucent forms, thus enabling a wide range of possible building application. For building applications, there are many properties to consider like building site adaptability and mechanical strength, fire protection, cost and environmental impact.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.11
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• pp.873-879
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• 2014

In the present study, water vapor is injected at various positions in a Clean Dry Air (CDA) system such as a system inlet duct, compressor inlet, and compressor outlet by humidified air turbines. The application of evaporative cooling reduces the compression work and enhances the Energy Consumption Index (ECI) per unit volume. The main purpose of this study is to investigate the compressor power performance with different inlet air temperatures and humidity conditions. It is found that the actual power consumption and discharge flow are significantly influenced by the inlet air temperature as well as relative humidity. The results obtained during this study are compared both numerically and experimentally and are found to be in very good agreement.

• Clean Technology
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• v.24 no.3
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• pp.166-174
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• 2018

Since particulate matter has high impacts on human health and everyday life, the dual fuel systems utilizing diesel and compressed natural gas have been developed to improve the environmental performance of diesel vehicles. The objective of this study is to estimate the economic feasibility of the dual fuel system based on real operating data of dual fuel buses and diesel buses. The system is economically feasible if the annual mileage of the dual bus is higher than 30,000 km, or if the unit fuel price of diesel is higher than that of CNG by 408 won. The uncertainty analysis results show that the economic feasibility of the system is probabilistically high, regardless of the variability of input data such as mileage and unit prices for the fuels. The sensitivity analysis results show that diesel and CNG prices are the highest contributor to the net present value of the system. Based on these results, economic incentives are suggested to disseminate the systems. This study would provide valuable economic information for bus business industry and policy maker to help make decisions for applying and disseminating the dual fuel systems to mitigate particulate matter problems.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.280-286
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• 2012

Clean energy farming is the agricultural activity to improve an efficiency of agricultural energy use and to replace fossil fuels. This study was carried out to establish the clean energy farming system in the controlled cultivation of vegetable crop (cucumber) adopting the biogas production facility. In order to design the clean energy farming system, mass and energy balance was analyzed between the controlled cultivation system and the biogas production facility. Net yearly heating energy demands ($E_{YHED}$) of forcing and semi-forcing cultivation types were 48,697 and $13.536Mcal\;10^{-1}$ in the controlled cultivation of vegetable cucumber. To cover these $E_{YHED}$, the pig slurry of 511 and $142m^3\;10a^{-1}$ (biogas volume of 9,482 and $2,636Nm^3\;10a^{-1}$, respectively, as 60% methane content) were needed in forcing and semi-forcing cultivation types. The pig slurry of $511m^3\;10a^{-1}$ caused N 1,788, $P_2O_5$ $511kg\;10a^{-1}$ in the forcing cultivation type, and the pig slurry of $142m^3\;10a^{-1}$ caused N 497, $P_2O_5$ $142kg\;10a^{-1}$ in the semi-forcing cultivation type. The daily heating energy demand ($E_{i,DHED}$) by the time scale analysis showed the minimum $E_{i,DHED}$ of $7.7Mcal\;10a^{-1}\;day^{-1}$, the maximum $E_{i,DHED}$ of $515.1Mcal\;10a^{-1}\;day^{-1}$, and the mean $E_{i,DHED}$ of 310.2 in the forcing cultivation type. And the minimum $E_{i,DHED}$, the maximum $E_{i,DHED}$, and the mean $E_{i,DHED}$ were 5.3, 258.0, and $165.1Mcal\;10a^{-1}\;day^{-1}$ in the semi-forcing cultivation type, respectively. Input scale of biogas production facility designed from the mean $E_{i,DHED}$ were 3.3 and $1.7m^3\;day^{-1}$ in the forcing and the semi-forcing cultivation type. The maximum $E_{i,DHED}$ gave the input scale of 5.4 and $2.7m^3\;day^{-1}$ in the forcing and the semi-forcing cultivation type.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.67-70
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• 2004

The purpose of this study is to develop the investigation technology of ground characteristics and environments using eco cone penetration system. The underground environments of landfill was investigated and analyzed by this eco cone system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in eco cone penetration system. This eco cone penetration system provides a continuous profile of measurements in underground, and provides repeatable, reliable and cost effective results for investigation of clean and contaminated ground.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.253-258
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• 2003

국민 1인당 쌀 소비량은 '90년 119.6kg 이었으나, '02년 87.0kg으로 급격히 감소하는 추세를 보이고 있다. 이는 국민 소득수준의 향상과 식품소비구조의 변화에 따른 것으로 쌀의 소비확대를 위해서는 이제 소비자의 욕구를 충족하는 고품질의 쌀을 공급해야 할 시전에 와 있다. 현재 유통되고 있는 일반 백미의 경우 소비자가 밥을 짓기 위해서는 쌀을 씻어야하는 번거로움뿐만 아니라 쌀 중량의 약 15배의 물이 소요되고, 또한 이때 발생된 쌀뜨물이 수질오염의 원인이 되기 때문에 무세미가공 및 보급 필요성이 점차 높아지고 있다. (중략)

• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.29-29
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• 2004

KVN (Korean VLBI Network) 시스템의 점광원이 아닌 천체에 대한 관측 능력과 효율을 알아보기 위하여, AIPS의 화상모의실험 프로그램인 UVCON을 사용하여 가상관측을 수행하였다. Cygnus A 및 M51의 실제 관측 자료와 원과 타원 모양 등 다양한 형태의 가상천체 자료에 대하여 UVCON을 수행하여 가상 UV 데이터를 만든 후, AIPS 표준 화상처리 과정을 거쳐서 각 실험 천체에 대한 clean Image를 생성하였다. 이 논문에서는 대상 천체의 입력 자료와 가상 관측 자료를 비교 분석한 결과를 발표한다. (중략)

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1798-1800
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• 2001

As a batch Type device, this machine is contrive to seal glass plates for plasma BLU (Back Light Unit) by indirect heating from electric heaters. In order to maintain the heating / cooling Chambers clean, this machine uses a muffle formation. The components of the machine are listed bellow.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.05a
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• pp.47-52
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• 1993

Recently, as exactly clean source, the research of photovoltaic power generation is undertaken actively and widely. In this paper, an auxiliary power supply system which is composed of photovoltaic generation and DC-DC boost chopper is described. This system in mainly for Air-conditioner appliances is which AC source is formed through rectifying circuit and without electrical storage battery. There exist two operating modes depending on the power quantity of the solar cells and the load. The control algorithm is discussed.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.101-102
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• 2000

반도체 생산에서 암모니아는 정밀성을 요구하는 공정 특히, 광증폭 공정에서 산과 반응하여 불량을 일으키는 주 원인이며, 고메모리로 갈수록 청정도 기준이 엄격해져서 1 ppbv 이하의 농도를 검출할 수 있는 기술이 요구되고 있다. 현재 반도체 회사에서의 암모니아 분석은 임핀저를 이용하여 가스를 포집한 후 이온크로마토그래피로 분석 하고 있으나, 이는 많은 시간과 인력이 요구되며, 실시간 분석이 어렵기 때문에 반도체 클린룸의 관리에 어려움이 있다. (중략)