• Journal of Hydrogen and New Energy
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• v.23 no.5
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• pp.559-571
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• 2012

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, and biomass. In addition to its environmentally friendly properties, DME has similar characteristics to those of LPG. The aim of this article is to represent the development of new DME process with KOGAS's own technologies. KOGAS has investigated and developed new innovative DME synthesis process from synthesis gas in gaseous phase fixed bed reactor. DME has been traditionally produced by the dehydration of methanol which is produced from syngas, a product of natural gas reforming. This traditional process is thus called the two-step method of preparing DME. However, DME can also be manufactured directly from syngas (single-step). The single-step method needs only one reactor for the synthesis of DME, instead of two for the two-step process. It can also alleviate the thermodynamic limitations associated with the synthesis of methanol, by converting the produced methanol into DME, thereby potentially enhancing the overall conversion of syngas into DME. KOGAS had launched the 10 ton/day DME demonstration plant project in 2004 at Incheon KOGAS LNG terminal. In the mid of 2008, KOGAS had finished the construction of this plant and has successively finished the demonstration plant operation. And since 2008, we have established the basic design of commercial plant which can produce 3,000 ton/day DME.

• Journal of Microbiology
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• v.44 no.6
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• pp.600-606
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• 2006

Spore forming actinobacteria (sporoactinobacteria) isolated from soils with an acidic pH in Pinus thunbergii forests and coal mine waste were subjected to taxonomic characterization. For the isolation of acidophilic actinobacteria, acidified starch casein agar (pH adjusted to 4-5) was used. The numbers of actinobacteria growing in acidic media were between $3.2{\times}10^4$ and $8.0{\times}10^6$ CFU/g soil. Forty three acidophilic actinobacterial strains were isolated and their 16S rDNA sequences were determined. The isolates were divided into eight distinctive phylogenetic clusters within the variation encompassed by the family Streptomycetaceae. Four clusters among them were assigned to the genus Streptacidiphilus, whereas the remaining four were assigned to Streptomyces. The clusters belonging to either Streptomyces or Streptacidiphilus did not form a monophyletic clade. The growth pH profiles indicated that the representative isolates grew best between pH 5 and 6. It is evident from this study that acidity has played a critical role in the differentiation of the family Streptomycetaceae, and also that different mechanisms might have resulted in the evolution of two groups, Streptacidiphilus (strict acidophiles) and neutrotolerant acidophilic Streptomyces. The effect of geographic separation was clearly seen among the Streptacidiphilus isolates, which may be a key factor in speciation of the genus.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.1
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• pp.92-103
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• 2004

This design was submitted to an invited competition for the Ski Resort of Kangwon Land which was held by Kangwon Land Resort in August, 2003. The site is located at 1∼17 Gohan-ri Gohan-eup Jungsungun Kangwon-do and has an area of 5,000,000$m^2$. The objectives of this project were to revitalize the local economy of Sabuk, Gohan which is well Down for deserted coal mines, by creating a resort complex for family group users with an environmentally friendly ski facility. This design scheme addresses three areas of concerns: First, how to boost the local economy through the proposed ski resort. By limiting lodging facilities in the ski resort, we could induce more development in the nearby towns. In order to balance the economical benefit to towns of Sabuk and Gohan, we decided to have two separate ski base facilities in each town boundary. Second, how to encourage family-oriented use of the ski resort by designing user-friendly ski slope, especially for beginner skiers. We designed 50% more beginner-level ski slope compared to average ski resorts. Third, how to make environmentally-friendly ski resort by respecting the original land form. We minimized the damage to the natural environment by protecting valuable tree groves. Also, ski slopes are designed to reduce unnecessary earth movement. This was designed under the assumption that more valley-oriented slopes would result in less cutting and banking of earthwork； this assumption was verified in comparison with other ski resorts. It is expected that this desist would serve environmentally-friendly designs in ski slopes.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.151-151
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• 2016

수소는 친환경 에너지원으로 주목 받고 있으며 미래 화석연료의 고갈에 대비할 수 있는 물질이다. 수전해는 natural gas steam reforming 또는 coal gasification 같은 방법에 비해 공해 물질의 방출이 없어 미래지향적인 기술로 간주된다. 저온형 수전해는 크게 알칼리 수전해와 고분자 전해질막 수전해로 구분되며 각각의 기술은 장단점을 가지고 있다. 알칼리 수전해는 비백금계 물질을 촉매로 사용할 수 있는 이점이 있으나 알칼리 용액으로 인한 부식, 높은 과전압에 의한 효율저하 그리고 간헐적인 사용에 적합하지 않다. 고분자 전해질막 수전해는 간헐적인 사용이 용이하고 높은 에너지 밀도를 가지지만 산성분위기로 인한 백금계 촉매를 사용해야 하므로 수소 생산 비용이 증가하게 된다. 본 연구에서는 알칼리 수전해와 고분자 전해질막 수전해 방식의 이점을 최대한 이용하고 단점을 극복하기 위한 방법으로 음이온 교환막(anion exchange membrane, AEM)을 적용한 셀 구조를 소개한다. 본문에서는 AEM 수전해 단위 셀의 구성요소들인 AEM 종류, 가스 확산층의 밀도와 운전조건인 알칼리 수용액 농도, 온도의 조건을 다르게 하여 최상의 구성 요소 조건 및 운전조건을 알아보았다.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.1-11
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• 2004

Gasification is the essential technology that can meet the interim hydrogen demand of large quantity before entering the hydrogen economy. Although the hydrogen production that is based upon the pure renewable energy like wind and solar power will eventually prevail, the interim mass production of hydrogen for the next ten to twenty years will come from the technologies that can demonstrate the economic feasibility in production cost with a high potential in minimizing CO$_2$ generation and in improving plant efficiency. Particularly, feedstock such as natural gas, coal, petroleum residual oil, wastes, and biomass appears to be utilized in Korea as hydrogen source, at least during the short and medium period of time, owing to the advantage in production cost. Because one of the main reasons behind the recent hydrogen issue is the reduction requirement of CO$_2$ that would be controlled according to the climate change protocol, hydrogen production technologies must be developed to yield the minimal CO$_2$ generation.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.75-83
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• 2002

The removal performance of copper ion was studied using Na-P1 zeolites synthesized from Jeju scoria. The scoria which is found in large amounts in Jeju Island, was sampled at four regions, Jeju-shi Bonggae-dong(A). Pukcheju-gun Hanlim-eup Sangmyong-ri Mangoreum(B), Pukcheju-gun Hanlim-eup Keumag-ri(C) and Namcheju-gun Andeok-myun Dongkwang-ri(D). Synthetic Na-P1 zeolites used in this study were more effective than natural zeolite and scoria for the removal of copper ion. The removal performances of copper ion decreased in the order of Na-P1(D) > Na-P1(C) > Na-P1(B) > Na-P1(A) among Na-P1 synthesized from the scoria according to region. These results showed the same trend with cation exchange capacity(CEC) for each synthetic zeolite, i.e., the synthetic Na-P1 zeolite with a higher CEC showed a higher removal performance. The effective diffusion coefficients of copper ion by synthetic Na-P1 zeolites were one hundred and ten times higher than those by a pure zeolite 4A and the zeolite A synthesized from coal fly ash, respectively.

• 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).

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.4
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• pp.408-421
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• 2016

Day and night sampling for gas and particle phases PAHs were carried out in Seoul to characterize gas and particle phases PAHs concentrations in day and night times. There was no significant difference between day and night time for particle phase PAHs concentrations and phase distribution of PAHs, while, gas phase PAHs concentrations in daytime were about 1/2 of nighttime concentrations in both summer and winter due to photochemical reaction of gas phase PAHs during daytime. A high fraction of cancer risk for PAHs was attributed to particle phase PAHs and the excess cancer risk in winter was higher than in summer. The excess cancer risk level of total(gas+particle) PAHs in summer was partially observed when both gas and particle phase PAHs concentrations were considered as risk assessment. Based on the diagnostic ratios and factor analysis of PAHs concentrations, combustion(coal and natural gas) and vehicular emission might be the most significant contributors of PAHs and major factors for determining of PAHs concentration were different between day and night times.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.143-155
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• 2018

The article compares economic and environmental performance of Taipei and Almaty from the point of view of "green" economy, which is able to act as a key tool to ensure sustainable development of the region. As the comparison of the parameters of ecological and economic development of the Taipei and Almaty cities shows, they are similar in population size, but demonstrate completely different trends of sustainable development. Economic performance of the Taipei city is achieved with a decrease in the consumption of natural resources and the production of pollution, while the situation in Almaty is the opposite. Almaty maintains a high level of air pollution due to the use of coal in electricity production, as well as increased traffic and density of construction, including the southern part of the city, which is a zone for the transit of mountain air flows. The article discusses the activities jointly conducted by the Government of Taiwan and non-governmental organizations on environmental issues, as well as environmental NGOs, which resulted in significant improvements in the environmental field. Measures to stimulate the development and implementation of environmental innovations applied in the field of sustainable development in the city of Taipei can be adapted for the city of Almaty, where the environmental situation deteriorates year by year.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.171-178
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• 2011

During the last decades, global warming from the increased amount of greenhouse gases, mainly carbon dioxide has become a major political and scientific issue. Burning fossil fuels (natural gas, coal and oil) releases $CO_2$, which is also a major cause of global warming. Among the clean environment, wood pellets are considered as promising renewable fossil fuels because of clean burning characteristics, reduction of particulate and NOx emission from combustion. In Korea, more than 50% pellets have to be imported every year because of shortage of feedstocks. On the other hand, about 80% of wood pulps are greatly dependent upon overseas products due to limited forest resources. Under this situation, this study explored how efficiently we have to use forest biomass instead of total dependence on wood as raw materials for pellets.