• Resources Recycling
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• v.19 no.1
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• pp.3-12
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• 2010

Recently, the waste energy utilization has become the main interest in energy industries, due to high oil prices, the low carbon, green growth policy and the RPS (Renewable Portfolio Standards) of our government. Therefore, energy guzzling companies such as district heating companies, textile industries are replacing energy to RDP/RPF. Especially, a lot of big companies are carrying out survey to commercialize the waste plastics pyrolysis technologies developed in Korea. In this paper, status of the pyrolysis technology of Korea were reviewed overall including basis of technology, waste plastics resources, research & development, and commercialization.

• Journal of Energy Engineering
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• v.29 no.2
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• pp.23-29
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• 2020

In this study, the last 10 years of news data on fine dust was collected and 80 topics are selected through LDA analysis. As a result, weather-related information made up the main words for the topic, and we can see that fine dust becomes a big issue below 10 degrees Celsius. The frequency of exposure to the media and the maximum concentration of fine dust are correlated with positive. Topics related to fine dust reduction measures and the government's comprehensive measures over the past decade, topics related to products such as air purifiers related to fine dust, topics related to policies protecting vulnerable people from fine dust, and topics on fine dust reduction through R&D were found to be major topics. Measures against fine dust as a social issue can be seen to be closely related to the government's policy.

• Journal of the Korean association of regional geographers
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• v.16 no.6
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• pp.689-705
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• 2010

The purpose of this study is to examine the geographical distribution and the clustering characteristics as an industrial cluster in order to provide alternative fundamental data for the preparation of the policies to facilitate the development of the Green Energy Industry. The main source of the data in this study is the outcome of a survey conducted to the firms and environment specialist from June 21st, 2010 to July 23rd, 2010. The Green Energy related companies in Daegyeong region are clustered around Pohang and Gumi, Gyeongbuk, and Dalseo District of Daegu Metropolitan City. The core element of the sustainability of the Green Energy Industry in the region is the inducement of the large-scale corporate presence in the region as well as the technical and geographical proximity. That is, the fact that there are sister companies established by the large scale corporate Daegyeong region as they have chosen this field for their new drive for growth. The major location factors are proximity, higher quality expectations from the local demands, technical availability, and competition with other companies of the same industry in the region, rather than the availability of the raw material. And the choke points for these companies are the financial support of R&D and the policy support of specialist training. The policy to facilitate the development of the industry in question in Daegyeong region, therefore, should shift from its previous focuses on infrastructure building and taxation benefits to financial supports for the technical research, human resource development in response to the needs of the companies. Also, programs to support the proficiency training for the already-hired work forces and development of new policies for the Green Energy Industry are needed to be introduced for the development of the Green Energy Industry in Daegyeong region.

• Journal of Adhesion and Interface
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• v.17 no.1
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• pp.7-14
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• 2016

Epoxy composites with concentrations of 5-70 wt% of silica particles were prepared in order to improve mechanical property and poor thermal stability. The mechanical and thermal properties were investigated and compared to the corresponding properties of neat epoxy composite. Furthermore, the effects of silane compound treatment on silica particles were observed by the experimental results of the tensile strength, glass transition temperature, and thermal stability of epoxy composite. Tensile strength of epoxy composites was measured by universal testing machine (UTM) and after that, the structure and morphology analysis of epoxy nanocomposites were analyzed by field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDS). The increased solid content of CA0030 particle improved the tensile strength of epoxy/ modified composites to give 30-50 MPa. The thermal expansion coefficients (CTE) of neat epoxy resin and epoxy/silica composites measured with a thermomechanical analyzer (TMA) showed that the incorporation of silica particles was helpful to reduce the CTE of neat epoxy resin.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.659-665
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• 2016

The oligosaccharides in human milk constitute a major innate immunological mechanism by which breastfed infants gain protection against infectious diarrhea. Clostridium difficile is the most important cause of nosocomial diarrhea, and the C-terminus of toxin A with its carbohydrate binding site, TcdA-f2, demonstrates specific abolishment of cytotoxicity and receptor binding activity upon diethylpyrocarbonate modification of the histidine residues in TcdA. TcdA-f2 was cloned and expressed in E. coli BL21 (DE3). A human milk oligosaccharide (HMO) mixture displayed binding with TcdA-f2 at 38.2 respond units (RU) at the concentration of 20 μg/ml, whereas the eight purified HMOs showed binding with the carbohydrate binding site of TcdA-f2 at 3.3 to 14 RU depending on their structures via a surface plasma resonance biosensor. Among them, Lacto-N-fucopentaose V (LNFPV) and Lacto-N-neohexaose (LNnH) demonstrated tight binding to TcdA-f2 with docking energy of −9.48 kcal/mol and −12.81 kcal/mol, respectively. It displayed numerous hydrogen bonding and hydrophobic interactions with amino acid residues of TcdA-f2.

• Applied Chemistry for Engineering
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• v.31 no.5
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• pp.575-580
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• 2020

In this study, we simulated an amine regeneration process with heat-stable salts removal unit. We derived the optimal operating conditions considering the flow rate of waste, the removal rate of heat-stable salts, and the loss rate of MDEA (methyl diethanolamine). In the amine regeneration process that absorbs and removes acid gas, heat-stable salt impairs the absorption efficiency of process equipment and amine solution. An ion exchange resin method is to remove heat-stable salts through neutralization by using a strong base solution such as NaOH. The acid gas removal process was established using the Radfrac model, and the equilibrium constant of the reaction was calculated using Gibbs free energy. The removed amine solution is separated and flows to the heat-stable salts remover which is modeled by using the Rstoic model with neutralization reaction. Actual operation data and simulation results were compared and verified, and also a case study was conducted by adjusting the inflow mass of removal unit followed by suggesting optimal conditions.

• Journal of Environmental Science International
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• v.25 no.4
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• pp.589-601
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• 2016

This study aims to analyze the priority of regional climate change policy utilizing AHP (analytic hierarchy process) at the area of Metropolitan City of Incheon. It derives four factors at first hierarchical level, at which level the analysis of pair-wise comparison indicates that industrial sector, energy sector, climate change response, and green culture policy are considered important in that order. It also ends up with sixteen factors at second level. The result of comparison analysis between all factors reveals that investment promotion in green technology R&D is considered the most significant factor of all, followed by establishment of green enterprise support system, electricity-efficiency enhancement support project and build-up of green culture policy governance. The result implies that diverse promotional policies have to incorporate business, institutional, and cultural aspects for sustainable climate change policy of regions. The contribution of this study is that it highlights the need to include regional characteristics in deciding priority among policy options for them to be effective.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.1
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• pp.83-90
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• 2011

Purpose: This study aimed to compare and assess whether there was a relation between self-reported symptom and stereopsis in viewing an anaglyph 3D and a general 2D image. Methods: Seventy subjects (38 males, 32 females) were students ranging in age from 20 to 30 years. Subjects' symptoms were investigated by a questionnaire after viewing the 2D image and the anaglyph 3D image using red-green glasses for 30 minutes. Titmus circles and TNO stereopsis tests were performed before and after the images. A correlation between symptom and stereopsis was evaluated. Results: Both ocular and nonocular symptom in viewing 3D image were higher than those in 2D image. Titmus circles stereopsises using polarized filters were not changed before and after viewing images, but TNO stereopsises using color filters such as red-green glasses were increased after viewing 3D image. Ocular symptom and TNO stereopsis were increased after viewing 3D image, and there was a good correlation between them (r=0.605). Conclusions: Better stereopsises before viewing 3D are relatively lower ocular symptoms in viewing 3D image. But symptoms are increased in viewing anaglyph 3D image for a short-time and improvement of TNO steropsis is poorly associated with the relief of ocular symptoms. This tendency seems to be related with an adaptation to anaglyph 3D image with red-green glasses.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.6
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• pp.107-116
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• 2012

In this study, the trucks(2.9-liter) have been developed to use DME as fuel, and performance test of the vehicle's DME engine, power, emissions, fuel economy and vehicle aspects was conducted. For experiments, the fuel system(common-rail injectors and high-pressure pump included) and the engine control logic was developed, and ECU mapping was performed. As a result, the rail pressure from 40MPa to approximately 65% increase compared to the base injector has been confirmed that. Also, the pump discharge flow is 15.5 kg/h when the fuel rail pressure is 400rpm(40MPa), and the pump discharge flow is 92.1 kg/h when the fuel rail pressure is 2,000rpm(40MPa). The maximum value of full-load torque capability is 25.5 kgfm(based on 2,000 rpm), and more than 90% compared to the level of the diesel engine were obtained. The DME vehicle was developed in this study, 120 km/h can drive to the stable, and calculated in accordance with the carbon-balance method of fuel consumptions is 5.7 km/L.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.4
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• pp.322-330
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• 2008

This paper deals with an economic evaluation of domestic photobiological hydrogen production. We evaluate the economic feasibility of domestic photobiological hydrogen production utilizing green algae and cyanobacteria. In addition, we make some sensitivity analysis of hydrogen production prices by changing the values of input factors such as the price of a photo-bioreactor and the value of solar to hydrogen efficiency. The estimated hydrogen production price of the two-step indirect biophotolysis was 12,099won/kg$H_2$. It is expected that the hydrogen production price by the two-step indirect biophotolysis can be reduced to 2,143won/kg$H_2$ if the solar to hydrogen efficiency is increased to 10% and the price of a photo-bioreactor is decreased to $25/$m^2$. The two-step indirect biophotolysis is evaluated as uneconomical at this time, and we need to enhance the solar to hydrogen efficiency and to reduce the prices of the photo-bioreactor and system facilities.