• 기계와재료
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• v.22 no.4
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• pp.6-20
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• 2010

현재 우리나라는 에너지 소비량의 97% 이상을 해외에 의존하고 있으며, 그 규모가 매년 증가하고 있는 실정이다. 이를 해소하기 위하여 다양한 시도가 이루어지고 있으며 이에 따른 관련 연구 분야의 정부 정책 지원도 증가하는 추세이다. 그러나 새로운 차세대 단열 소재의 개발을 통한 에너지 절감에 대한 노력은 아직 미흡한 상태이다. 본고에서는 이와 관련하여 에너지 효율 극대화 방안으로써, 기존의 단열 소재의 현황 및 향후 단열 소재의 연구방향을 다공질 세라믹(특히 에어로겔)을 중심으로 정리 기술함으로써 앞으로의 발전방향을 제시하고자 한다. 또한 이를 통하여 전체적인 다공성 무기질 단열 소재에 대한 이해를 높여 향후 친환경적이며, 에너지 효율적인 단열소재 연구 분야를 확립하는데 기여하고자 한다.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.3
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• pp.244-249
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• 2011

This in vitro study compared the remineralization of incipient interproximal caries in the presence of three glass ionomer cements(highly-filled glass ionomer cement, resin-modified glass ionomer cement, compomer) and a resin composite(control). Thirty-two extracted premolars were selected based upon the lack of any visible demineralization. The teeth were coated in a transparent acid resistant nail varnish leaving $3{\times}3$ mm square. The teeth were subjected to the demineralizing buffer for 3 days and quantitative light-induced fluorescence(QLF) images of the subjects were taken. Proximal restoration was simulated by placing tooth specimens and the various glass ionomer cements in closed containers with artificial saliva at $37^{\circ}C$ and pH 7.0 with constant circulation. Further QLF images were subsequently taken at 30, 60, and 90 days. The changes of mineral loss(${\Delta}Q$) were evaluated by QLF and the change of ${\Delta}Q$(${\Delta}{\Delta}Q$) were compared between groups in order to evaluate the effects of remineralization. All data were analyzed using ANOVA and the post-HOC Dunnett C multiple comparison test at p<0.05. While ${\Delta}Q$(changes of mineral loss) increased for all treatments, the increases for three glass ionomer groups were significantly higher than that for the resin group at first month period. As time went on, the amount of ${\Delta}{\Delta}Q$ decreased.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.293-300
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• 2019

As a common side effect of fixed orthodontic treatment, demineralization of the enamel adjacent to the bracket and band occurs in patients with poor oral hygiene. The purpose of this study was to investigate what is the most effective method to prevent demineralization around the fixed orthodontic appliance among various methods using fluoride. 80 extracted bovine incisors with a healthy surface were classified into four groups as experimental materials: (Group I) Control group, (Group II) V $varnish^{TM}$, (Group III) Tooth Mousse $Plus^{(R)}$, (Group IV) $Vanish^{TM}$ XT. After treatment for each group, mineral loss and Vickers surface microhardness were measured at 0, 30, 60 and 90 days after demineralization in artificial carious solution. Mineral loss was the lowest in group IV, followed by group II and group III, which showed a significant difference. The surface microhardness was the lowest in group IV, followed by group II and group III, which showed a significant difference. Through this study, group IV showed the best effect to prevent enamel demineralization around the bracket. Group III showed significant prevention of enamel demineralization compared with the control group, but the effect was less than that of the other groups.

• The Korean Journal of Food And Nutrition
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• v.27 no.6
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• pp.1059-1066
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• 2014

In this study, the nutritional value, total polyphenol content, total flavonoid content, and antioxidant activity of freeze-dried Cedrela sinensis tender leaf powder were examined. Among the nutritional values, the crude protein, crude fiber, calcium, and potassium were abundantly present in Cedrela sinensis. The Cedrela sinensis powder was extracted with two solvents, 70% ethanol and distilled water (D.W.), to evaluate its functional properties. Total polyphenol and flavonoid contents were measured in the two different extracts, and the extracts were screened for their potential antioxidant activities using tests such as DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), and ABTS radical scavenging assay. Although both extracts exhibited good antioxidant activities against trolox, the ethanolic extract exhibited higher antioxidant activities than the D.W. extract. These results indicated that the Cedrela sinensis powder is a high-valued food ingredient and the extraction with 70% ethanol will be useful as a nutritional source with natural antioxidant activities.

• Culinary science and hospitality research
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• v.8 no.2
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• pp.207-215
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• 2002

This study was carried out in order to investigate the study on the characteristics of nutrient content and sensory evaluation of functional rice Dasik Rice Dasik was prepared with 0, 1, 2, 3 and 4% concentration of mulbeyry-leaf powder and silkpeptide powder. Increasing mulberry-leaf powder and silkpeptide powder led to the significant increase in the contents of crude protein and crude ash. The contents of Ca, K and Mg of mulberry-leaf powder and silkpeptide powder groups were higher than those of the mulberry-leaf powder and the silkpeptide powder free group. And the sensory evaluation of the rice Dasik with 2% mulberry-leaf powder and silkpeptide powder were found to be significantly higher than those of other groups.

• Journal of Conservation Science
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• v.26 no.4
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• pp.361-370
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• 2010

The open pore of stone cultural heritage is not expected to have an effect only by consolidation, and it has a drawback that only the internal wall adheres and gets consolidated due to the incrase of liquidity caused by the low viscosity and difference of materials in the case of filling with high molecules synthetic resins. Therefore, this research selected the effective filler for Three-storied Stone Pagoda at the West of Gameunsaji Site through the verification of filling effects of materials using the information about various fillers based on minerals. As the result of filler experiment, got filled with the combination of KSE 500 STE + KSE Filler A${\cdot}$KSE Filler B that is the same as the Member or has very similar properties. The total surface area of the west stone is $252.6m^2$ and the area where the internal opening has been developed is $17.77m^2$(7.03%) requiring a task that fills the internal($24,885m{\ell}$).

• Journal of Life Science
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• v.19 no.2
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• pp.192-197
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• 2009

This study was conducted to investigate the major chemical components of dried broccoli (Brassica oleracea var. italica Plenck) sprouts. The proximate compositions of broccoli sprouts as dry matter basis were 2.04% of moisture content, 22.04% of crude protein, 12.80% of crude fat, 6.25% of crude ash, and 56.87% of carbohydrate, respectively. The major free sugars were identified as ribose, glucose and fructose. Analysing total amino acids, 15 kinds of components isolated from broccoli sprouts. The essential amino acid contained in broccoli sprouts accounted for 45.62% of total amino acid, while the non-essential amino acid accounted for 54.38%. Fatty acids were 3.19% of saturated fatty acids, 14.42% of monounsaturated fatty acids and 82.39% of polyunsaturated fatty acids. Cis-11,14-eicosatrienoic acid, linoleic acid and oleic acid were the major fatty acids among 14 fatty acids detected in dried broccoli sprouts. Lactic acid was the major organic acids. The contents of vitamin A and vitamin E were 0.06 mg% and 0.82 mg%, respectively. The mineral contents of dried broccoli sprouts were greater in order of Cu

• Journal of the Korea Concrete Institute
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• v.17 no.5 s.89
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• pp.679-686
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• 2005

The corrosion of reinforcement induced by chloride ingress is the main deterioration cause of coastal reinforced concrete structures. In this paper, an experimental study was executed to investigate the effect of the kinds and replacement ratios of mineral admixtures (fly-ash, ground granulated blast-furnace slag silica fume and meta-kaolin), W/B and curing time on chloride diffusion of concrete by long-time immersion test in chloride solution. According to the result, the use of mineral admixtures was effective in improving the resistant to chloride ingress. The chloride penetration depth and diffusion coefficient were decreased as replacement ratios of mineral admixture were increased. The kind and replacement ratio of the mineral admixture are more important than the W/B in reducing the chloride diffusion of concrete. Chloride binding capacity of mineral admixture, which was sequenced in the order of MK

• Journal of Digital Convergence
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• v.14 no.12
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• pp.583-590
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• 2016

This study aims to suggest a desirable dietary methods based on the oriental medicated dietary effects based on the schema of four qi and five flavors of foods originated from the yin-yang and five phase theory through clear understanding of the theory of oriental medicated dietary in a modern point of view, and through experimental analysis on the nutrient and dietary effect of 4 medicinal plants. We expect it can show us the way for promoting more healthy life styles and for preventing adult diseases by following our own medicated dietary theory. We should develop our own culinary and dietary culture which is suitable for our physical and genetic conditions for our healthy and happy lives. To successfully develop and introduce them, we should analyze their dietary effects scientifically based on both the theory of nutrialogy and the oriental medicated dietary in a modern point of view.

• Electrical & Electronic Materials
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• v.1 no.2
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• pp.136-148
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• 1988

본 논문은 Epoxy수지에 무기물을 첨가하여 tracking 특성에 미치는 자외선 조사의 영향을 연구하였다. 시료는 Bisphenol A형 Epoxy수지에 충진제 MgO와 Al(OH)$_{3}$를 각각 첨가한 시료와 무기물을 첨가하지 않은 무층진 시료에 대하여 자외선을 조사하여 산화 및 열화현상과 tracking현상을 비교 연구 검토하였다. 그 결과 자외선조사로 인하여 carbonyl기의 생성과 craze의 발생이 있었고 이는 tracking 파괴와 침식을 용이하게 한다. 그리고 Epoxy수지에 충진제를 첨가하므로서 자외선에 의한 열화를 감소시키고 내 tracking성을 향상시킨다.