• Journal of Radiation Industry
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• v.7 no.1
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• pp.51-54
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• 2013

Chitosan is a useful natural polymer material in many application fields such as biomaterials, water-treatment, agriculture, medication, and food science. However, the poor solubility limits its application. In this study, the effects of radiation on chitosan were investigated using gamma ray and electron beam irradiation. The chemical structure and molecular weight analysis show similar degradation effects of chitosan powder in both gamma ray and electron beam irradiation. However, the radiation irradiated chitosan in $H_2O$ has a lower molecular weight, since the hydroxyl radicals attack the glycosidic bonds. This effect is more clearly shown in the electron beam irradiation results.

• Journal of Radiation Industry
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• v.9 no.1
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• pp.9-13
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• 2015

Epoxy resin is widely used as aerospace, automobile, construction and electronics due to their good mechanical and electrical properties and environmental advantages. However, the inherent flammability of epoxy resin has limited its application in some field where good flame retardancy is required. Nano clay can enhance the properties of polymers such as flames retardancy and thermal stability. In this study, we have investigated the nanoclay filled epoxy composite, which has good flame retardancy while maintaining high mechanical properties. The cured epoxy resins were obtained using an electron beam curing process. The nano clays were dispersed in epoxy acrylate solution and mechanically stirred. The prepared mixtures were irradiated using an electron beam accelerator. The composites were characterized by gel content and thermal/mechanical properties. Moreover, the flammability of the composite was evaluated by limited oxygen index (LOI). The flame retardancy of nano clay filled epoxy composite was evidently improved.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.45-49
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• 2013

In tissue engineering application, a fibrous structure of scaffolds has been issued as an alternative system to regulate cell survival and tissue regeneration, and electrospinning technique has been popularly used to generate fibrous meshes or sheets mimicking the structure of native extracellular matrix (ECM). However, recent strategy in the scaffold development is expanded to provide the structural property as well as a biological property of native ECM, a variety of surface modification techniques have been used to introduce biological property. In this study, we developed biomimetic poly(L-lactide-co-${\varepsilon}$-caprolactone) (PLCL) nano- and micro-fibrous scaffolds as a unique platform with structural and biological properties with native ECM using electrospinning method and gamma-ray irradiation. Surface morphology of the scaffolds was observed by scanning electron microscopy, and alteration of surface property was evaluated with toluidine blue O staining, water contact angle measurement and ATR-FTIR analysis.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.87-91
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• 2013

Taraxacum platycarpum (TP) has been used for years without restriction on usual dose for its non-toxic nature and nonexistence of the side effects. To develop antimicrobial hydrogel, poly (vinylalcohol) (PVA) hydrogels containing the aqueous extracted TP as an antimicrobial agent were prepared by using gamma-rays irradiation. The antimicrobial activities of the TP hydrogels were tested against Staphylococcus aureus and Staphylococcus epidermidis by disc diffusion method. The inhibition zones (IZ) of the TP extracts and TP hydrogels against S. aureus were 16 mm and 20 mm and against S. epidermidis was 10 mm and 13 mm, respectively. In conclusion, the TP hydrogel that has an excellent antimicrobial activity was proved to be a valuable material for functional skin care.

• Journal of Radiation Industry
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• v.9 no.2
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• pp.77-84
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• 2015

The stainless steel mesh coated with poly(acrylic acid) hydrogel was fabricated and applied for the separation of water and oil. The stainless steel mesh was immersed in aqueous poly (acrylic acid) solution, and then irradiated by radiation to introduce poly(acrylic acid) hydrogel on the surface of mesh by crosslinking. It was possible to separate oil and water from mixtures of oil/water effectively using the hydrogel-coated mesh. The effect of irradiation dose, coating thickness, size of mesh on the separation efficiency was examined.

• New & Renewable Energy
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• v.7 no.1
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• pp.8-14
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• 2011

As is the case in Korea, the expansion of renewable energy dissemination is an essential matter in Ukraine when considering its energy consumption and dependence on energy import. While Korea has set about promoting the new and renewable energy industry on the back of the national policy on green growth, Ukraine expects a virtuous circle of renewable energy industry with green tariffs and the attraction of foreign capital in association with carbon emission trade. Utilizing its well-developed heavy industrial sector including the shipbuilding and automobile industries, Korea expects wind turbine manufacturing to become one of its next-generation growth engines. Ukraine is also trying to enter the wind turbine system or parts manufacturing industry based on its automobile industry and advanced aerospace technology. Although the Crimean region in Ukraine seems to have excellent wind resources, and thus shows great potential as a location for wind farm development, political instability has been a major obstacle to the attraction of foreign capital, leading to delayed investment.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.57-63
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• 2017

This study aimed at proposing a RD&D good practice policy guidelines for energy technology innovation in electric power industry, we identified the success factors on energy RD&D through representative case analysis such as energy RD&D demonstration project and strategy plan, technology road map, etc. Based on a successful case study, we have identified the key elements needed to suggest when setting a RD&D technology innovation policy framework for technological competitiveness in the power industry sector. We have presented guidelines for energy technology innovation direction from the full cycle perspective of RD&D. The energy RD&D innovation system that we have established is meaningful in that the implications are derived and reflected through the case analysis of developed countries. The results of this study are as follows; Enhancement of R&D investment performance, commercialization of research achievements, promotion of export industrialization of electric power industry, establishment of RD&D governance system of power energy, etc.

• Journal of Energy Engineering
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• v.21 no.1
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• pp.109-117
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• 2012

The climate industry could be defined as the group of industries responding to world climate change compacts. This study confined it to renewable energy and analyzed the economic impacts of Korean renewable industry, using 2009 Input-Output Table. This study estimated that Korean renewable industry made the production-induced impact of 1.1644 won(Korean money), and the value-added-induced impact of 0.3544 won through an increase in output growth of 1 won. Its job-creation impact is analyzed to correspond to 10.065 labors through an increase in output growth of 1 billion won. And its industrial linkage effects including forward and backward ones are analyzed not to be so great as expected. According to these results, some policies vitalizing Korean renewable industry and relating industries to its value-chain as new growth engines are recommended.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.577-584
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• 2005

There are many activities involved in promoting renewable energy technologies. These include governments, the renewable energy manufacturing and service industries, energy supply companies, investors, researchers, non-government organizations and customers. For a sustainable renewable energy market, finding a promising industry is essential. The industry has made significant progress in recent years, considering the fact that today's renewable energy market is relatively small. This paper analyses the technology market of renewable energy, focusing on photovoltaic system, fuel cell, wind system. It appears that there has been remarkable progress in renewable energy systems. Besides, developed countries are effectively increasing the share of niche market and promoting renewable energy worldwide.

• Journal of Radiation Industry
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• v.12 no.4
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• pp.343-348
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• 2018

Preliminary study was perfomed to develop a biocompatible filter material using radiation energy. Electrosppined PLLA nano sheets were surface-modificated with hydrophilic groups(acrylic group) by using radiation. The physico-chemical and morphological characteristics of modified PLLA sheets were measured by ATR, SEM, contact angle, and hydrophilic (acryl group) introduction rate (TBO). As a result, there was no morphological(fiber structure) structure change due to radiation, and it was confirmed that an acrylic group was successfully introduced onto PLLA fiber sheet by radiation.