• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.125-131
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• 2006

Dimethyl ether (DME) is a new clean fuel as an environmentally-benign energy resource. DME can be manufactured from various energy sources including natural gas, coal, biomass and spent plastic. In addition to its environmentally friendly properties, DME has similar characteristics to those of LPG. Therefore, it is considered as an excellent substitute fuel for LPG, fuel cells, power plant, and especially diesel and is expected to be the alternative fuel by 2010. The experimental study of the direct synthesis of DME was investigated under various conditions over a temperature range of $220{\sim}280^{\circ}C$, syngas ratio 1.2~3.0. All experiments were carried out with a hybrid catalyst, composed of a methanol synthesis catalyst ($Cu/ZnO/Al_2O_3$) and a dehydration catalyst (${\gamma}-Al_2O_3$). The observed reaction rate follows qualitatively a Langmiur-Hinshellwood model as the reaction mechanism. Such a mechanism is considered with three reactions; methanol synthesis, methanol dehydration and water gas shift reaction. From a surface reaction with dissociative adsorption of hydrogen, methanol, and water, individual reaction rate was determined.

• Journal of Soil and Groundwater Environment
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• v.9 no.3
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• pp.20-26
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• 2004

In-situ photolysis is one of the most promising ways to clean up a soil contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). This study focuses on the mathematical description and model development of the convective upward transport of an organic solvent driven by evaporation and photodecomposition at the surface as the major transport mechanism in the clean up process. A finite-element-based numerical model was proposed to incorporate effects of multiphase flow on the distribution of each fluid, gravity as a driving force, and the use of van Genutchen equation for more accurate description of k-S-p relations. This paper presents results of extensive numerical calculations conducted to investigate the various parameters that play a role in the solvent migration through a laboratory-scale unsaturated soil column. The numerical results indicate that gravity affects significantly on the fluids distribution and evaporation for highly permeable soils. The soil texture has a profound influence on the fluid saturation profile during evaporation process. The amount of solvent convective motion increases with increasing evaporation rates and decreasing initial water saturation. Simulations conducted in this study have shown that the developed model is very useful in analyzing the effects of various parameters on the convective migration of an organic solvent in the soil environments.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.272-275
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• 2009

Carbon finance is the investment in Greenhouse Gas (GHG) emission reduction projects in developing countries and countries with economies in transition within the framework of the Kyoto Protocol's Clean Development Mechanism (CDM) or Joint Implementation (JI) and with creation of financial instruments, i.e., carbon credits, which are tradable in carbon market. The additional revenue generated from carbon credits will increase the bankability of projects by reducing the risks of commercial lending or grant finance. Meantime, it has also demonstrated numerous opportunities for collaborating across sectors, and has served as a catalyst in bringing climate issues to bear in projects relating to rural electrification, renewable energy, energy efficiency, urban infrastructure, waste management, pollution abatement, forestry, and water resource management. Establishing additionality is essential for successful CDM project development. One of the key steps is the investment analysis. As guided by UNFCCC, financial indicators such as IRR, NPV, DSCR etc are most commonly used in both Option II & Option III. However, economic indicator such as Economic Internal Rate of Return(EIRR) are often overlooked in Option III even it might be more suitable for the project. This could be due to the difficulties in economic analysis. Although Asian Development Bank(ADB) has given guidelines in evaluating EIRR, there are still large amount of works have to be carried out in estimating the economic, financial, social and environmental benefits in the host country. This paper will present a case study of a CDM development of a 18 MW hydro power plant with carbon finance option in central Vietnam. The estimation of respective factors in EIRR, such as Willingness to Pay(WTP), shadow price etc, will be addressed with the adjustment to Vietnam local provincial factors. The significance of carbon finance to Vietnam renewable energy development will also be addressed.

• Journal of Agricultural Extension & Community Development
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• v.19 no.1
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• pp.147-178
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• 2012

청정개발체제(CDM)는 1997년 교토의정서(Kyoto protocol)를 통해 확립된 온실가스 배출과 관련된 선진국과 개도국 간 협력 기제의 하나이다. 청정개발체제는 기본적으로 선진국의 정부 또는 민간조직이 개도국에서 배출감축 프로젝트를 수행하고, CER(Certified Emission Reduction)의 형태로 배출권을 얻는 것을 허용하고, CER을 자국의 배출감축목표 달성을 위해 사용할 수 있도록 하고 있다. 이 연구의 목적은 아세안 국가들의 청정개발 메커니즘의 성취도를 알아보는데 있으며, 자료는 2010년 10월 15일 현재 유엔기후변화기본협약(UNFCCC)에 등록된 254개 청정개발체제 사업을 대상으로 분석하였다. 이 연구의 결과, 전체 254개 사업 중 20%만이 탄소배출권을 받은 것으로 나타났으며, 실제 탄소배출권의 총량은 650만 톤이지만, 이는 전체 사업계획서에 반영된 양의 15%에 불과한 것으로 분석되었다. 또한 아세안 국가의 CDM사업과 관련된 장애 요인으로서는 (1) 사업 등록과 탄소배출권 승인 간 시간 격차가 존재하고, (2) 사업계획과 실제 승인량에 차이가 나타나며, (3) 특히 소규모 사업의 경우 높은 거래 비용 때문에 등록 후 배출승인을 신청하지 않고 있는 것으로 나타나고 있다. 이러한 연구결과는 아세안국가들이 CDM사업을 수행하는 데 있어서 선진국들의 주요 파트너가 되고 있지만, 실제로 사업을 통한 탄소배출량은 제한적일 수 있음을 의미한다. 따라서 일부 아세안 국가에서 교토의정서에 따라 자체적으로 탄소배출감축을 시도하고 있음을 고려할 때, 자체적인 CDM의 성공적인 경영, 수행, 운영을 위해 더 많은 선진국들의 협력과 지원이 주어질 필요가 있다.

• Journal of Environmental Impact Assessment
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• v.17 no.5
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• pp.321-330
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• 2008

Methane is a potent greenhouse gas and methane emissions from landfills have been linked to global warming. In this study, LandGEM (Landfill Gas Emission Model) was applied to predict landfill gas quantity over time, and then this result was compared with the data surveyed on the site, Cheongju Megalo Landfill. LandGEM allows the input of site-specific values for methane generation rate (k) and potential methane generation capacity $L_o$, but in this study, k value of 0.05/yr and $L_o$ value of $170m^3/Mg$ were considered to be most appropriate for reflecting non-arid temperate region conventional landfilling, Cheongju Megalo Landfill. High discrepancies between the surveyed data and the predicted data about landfill gas seems to be derived from insufficient compaction of daily soil-cover, inefficient recovery of landfill gas and banning of direct landfilling of food garbage waste in 2005. This study can be used for dissemination of information and increasing awareness about the benefits of recovering and utilizing LFG (landfill gas) and mitigating greenhouse gas emissions.

• The KSFM Journal of Fluid Machinery
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• v.12 no.3
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• pp.31-37
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• 2009

This paper presents a implantable intrathecal drug infusion pump for pain control in cancer patients. This device consists of micropump module, drug reservoir module and control module. The micropump module using cam-follower mechanism composed of small-sized four cams and four followers. Each followers is driven by a cam and liquid is discharged by a sequential reciprocal motion of the followers. The advantage of this structure is that it allows the pump to be clean and valveless. The drug reservoir module composed of drug chamber, gas chamber and diaphragm. The control module composed of battery, wireless communication unit and controller. To design a small-sized, low power pump some analysis were performed to determine the design parameters. To verify the feasibility of the experiment, a prototype was manufactured and its operating characteristics were investigated. Experimental results were in accordance with the expected results obtained from analysis.

• New & Renewable Energy
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• v.3 no.4
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• pp.104-113
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• 2007

교토의정서(Kyoto Protocol)의 발효로 전 세계적으로 에너지절약형 산업구조로의 전환 및 신재생에너지 개발 등의 온실가스 감축을 위한 노력이 활발하게 진행되고 있으며, 우리나라 또한 온실가스 저감을 피할 수 없게 되었다. 특히 선진국(Annex I)의 구속력 있는 감축목표를 규정하고 있는 교토의정서의 의무이행에 유연성을 부가하기 위해 교토메카니즘이 채택되었다. 교토 메카니즘은 CDM(Clean Development Mechanism), JI(Joint Implementation), ET(Emission Trading)로 이루어져 있으며, 이 가운데 CDM 사업은 선진국(Annex I)과 개발도상국 non-Annex I)간 공동 협력 사업으로 non-Annex I 국가인 우리나라가 참여할 수 있기 때문에 국내 기업 및 정부의 관심이 높아지고 있다. 이러한 CDM 사업을 수행하기 위해서는 적용 가능한 CDM 사업 방법론이 필요하며, 방법론이 없을 경우 CDM 사업 방법론을 개발하여야 한다. CDM사업 방법론에는 레이스라인, 추가성, 배출 감축량, 모니터링 등에 대한 구체적인 방법이 제시되어야 하고 사업 수행자는 사업의 타당성 확인 및 검증을 위해 방법론을 정확히 이해해야 한다. 따라서 본 CDM사업 방법론 연구를 통해 CDM사업 수행 및 방법론 개발을 위한 주요 항목의 이해를 돕고 국내 CDM 사업의 활성화를 도모하고자 한다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.806-812
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• 2009

Availability of reliable and affordable energy supply is a prerequisite for economic growth. Renewables are the third largest contributor to global electricity production after coal and natural gas and account for a share of 18%. Power generating capacity from renewables has increased to around 900GW by the year 2007. Today biodiesel fuels have been in commercial use in many countries and recently the world-wide biodiesel market has experienced considerable growth, which is partly due to various tax concession programs and other financial incentives. In Korea, biodiesel has already been used for transportation fuel, but not used for power generation fuel yet. Korean government has a strategy for renewable energy propagation, especially the goal of power generation amount by renewable energy is 3% of total power production by 2012. This paper focuses on the feasibility study for adaptability and strategy of using biodiesel as power generation fuel. The study also has the plan to replace the fuel of thermal power plant, gas turbine and distributed power system. As the increase of biodiesel fuel, I look forward to environment-friendly power generation and the strategy of Renewable Portfolio Standards(RPS).

• Environmental and Resource Economics Review
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• v.9 no.1
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• pp.127-153
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• 1999

청정개발체제(CDM)란 '기후변화의 부정적 효과 완화'와 '개도국의 지속 가능한 발전 지원'이라는 기후변화협약의 양대 목표를 비용 효과적으로 이행하기 위해 교토의정서에 마련된 수단이다. CDM은 선진국인 부속서 I 국가와 이에 해당하지 않는 비(非)부속서(non-Annex) I 국가 즉 개도국이 배출감축을 위해 공동으로 노력하고 그 결과 창출된 온실가스 감축 분을 이 두 그룹 국가간에 배분되도록 한 제도다. 즉 선진국은 개도국에 자본과 기술을 투자하여 온실가스 저감사업을 벌이고 이 과정에서 발생한 온실가스 배출감축 분을 자국의 감축실적(credits)으로 인정받게 되고, 개도국은 이 과정에서 기술이전 및 재정지원의 혜택을 받을 수 있게 되어 있다. CDM은 따라서 세계 대다수의 국가가 직 간접으로 영향을 받지 않을 수 없을 것이며, 이로 인해 CDM의 구체적 실천 방안을 둘러싸고 각 국간의 이해 관계가 좀처럼 좁혀지기 어려운 상황이다. 이에 따라 지난해 부에노스 아이레스에서 개체되었던 COP-4에서는 CDM 체제를 비롯한 기후변화협약의 핵심 쟁점사항을 오는 2001년(또는 2002년)에 개체될 COP-6까지 일괄 타결키로 한 부에노스 아이레스 행동계획을 채택하는 데 그쳤다. CDM이 향후 어떤 형태로 결정되는 가에 따라 우리 나라가 받는 영향도 상당한 차이가 날 것이다. 따라서 CDM의 전개 방향을 면밀히 주시하고 이에 대한 대응책 마련이 절실히 요구되고 있다.

• Journal of Energy Engineering
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• v.27 no.2
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• pp.61-69
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• 2018

Rare earth elements together with Y and Sc (REEs) are essential in the development of technology for clean and efficient use of energy. In recent years coal deposits have much attention and attracted as a promising alternative raw sources for rare earth elements, not only because the REEs concentrations in many coals or coal ashes are equal to or higher than those found in conventional types of REEs ores but also because of the world wide demand for REEs in recent years has been greater than supply. In the coal ashes, REEs are mainly associated with carbonates, silicates and aluminosilicates in ashes at 800 and $1100^{\circ}C$. These elements are known to be powerful environmental tracers in natural biogeochemical compartments. In this study, to reviewed the REEs originating and distribution patterns in coal ash samples from the bedrock and/or soil weathering that were entrapped by lichens and mosses was investigated. The REEs patterns of different organisms species allowed minor influence of the species to be highlighted compared to the regional lithology.