• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.331-335
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• 1999

The transition metal oxides have been of interest as bifunctional electrocatalysts for bifunctional air electrodes. The amorphous citrate precursor (ACP) process has been optimized to prepare perovskite (La0.6Ca0.4CoO3) and pyrochlore (Pb2Ru2O6) powders with high surface area, and consequent improvement of The electrocatalytic performance in an air electrode with thermal treatment. PTFE -bonded gas diffusion electrodes loaded with perovskitc and pyrochlore catalysts showed good bifunctional performances. The electrodes were fairly stable up to 100 hour in the galvanostatic mode at ${\pm}25mA/cm^2$, from which these electrodes offer promise as practical bifunctional air electrodes.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.694-700
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• 1992

Aromatic polyamides and polyesters with fexible spacers are prepared by Heck reaction with palladium catalysts In presence of carbon monoxide gas. Dichlorobis(triphenyl phosphine) plladium(II) ($PdCl_2(PPh_3)_2$) and palladium chloride ($PbCl_2$) are used as catalysts. Polyamides and polyesters prepared by his polymerization system have similar transition temperatures. Flexible spacer substituted on phenylene units are varied from hexyl to hexadecyl, the length of spacers effected on transition temperatures of substituted polymers.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.651-657
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• 1999

These experiments focused on processing low sugar fig jam having marketability by selected substitute for extracted and purified pectinesterase (PE), colorant for colour improvement, food additive to make texture better, and stabilizer for stable storage. Cherry tomato pulp as PE substitute to hydrolyze pectin substance in fig pulp into low-methoxyl pectin was most effective among used vegetables and fruits pulp. Carmacid-R among natural colorants for imprving colour, addition of 20% starch syrup as sugar substitute for texture and addition of $MULTIPHOSE^{TM}$ for red colour change control at cold storage were effective. The low sugar fig jam processed by using the above selected materials showed higher score than others (typical jam and orange PE low sugar fig jam) for colour in sensory evaluation and did no significant difference in taste, odor, texture and overall acceptability.

• Animal Systematics, Evolution and Diversity
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• v.6 no.1
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• pp.17-28
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• 1990

Electrophoretic methods were used to examine the degree of genic variation and genetic relatedness in 11 populations representing 6 species and subspecies of the genus Parus in Korea. The average degree of genic variation of 3 subspecies of P. major was =1.2, =24.4% , D=0.042, and G=0.058, whereas the rest of the species showed slightly lower degree of genic variation than P. major. Genetic relatedness between subspecies and species in the genus Parus showed similar to those reported at comparable taxnonomic levels in other birds. But it appears to be considerably less than that of non avian taxa. Genetic relatedness between 3 subspecies of P.major and P. varius varius was closely related(=0.80), whereas between P.palustrius hellmayri and P.ater amurensis was relatively remote (=0.67). The presumed divergent times of P.palustrius hellmayri, P, ater amurensis , and P. varius varius were about 1.8, 1.6, and 1.0million years before present respectively, and 3 subspecies of P. major were recently differentiated about 100 thousands years before present.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.417-419
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• 2011

태양전지 모듈은 back sheet, 후면 충진재, 태양전지 cell, 전면 충진재, 전면 보호유리의 구성으로 되어 있다. back sheet는 유리 또는 금속을 사용하는데 사용 재료에 따라 각각 유리봉입방식, 슈퍼스트레이트방식으로 구분된다[1]. 태양전지를 보호하기 위한 충진재는 빛의 투과율 저하가 적은 PVB(Poly Vinyl Butylo)나 내습성이 뛰어난 EVA(Ethylene Vinyl Acetate) 등이 주로 이용된다. 유리봉입방식과 슈퍼스트레이트 방식의 공통점은 모듈 전면에 투과율과 내?충격 강도가 좋은 강화 유리를 사용하는 것이다. 하지만 현재 모듈의 전면 유리는 평탄한 표면 때문에 태양고도가 낮을 때 상대적으로 반사율이 높은 단점을 가지고 있다[2]. 이러한 문제점을 해결하기 위한 방안으로 표면 유리에 요철(anti-glare) 구조를 형성하면 평면 구조의 표면에서 반사되는 태양광이 일부 태양전지 내부로 재입사가 일어나게 되어 표면 반사율이 낮아지게 되고, 이로 인하여 태양전지의 효율이 증가하게 된다. 특히 이러한 효과는 태양고도가 낮아졌을 때 요철(anti-glare) 구조에 의한 반사율의 감소가 증가하기 때문에 평면 구조보다 요철(anti-glare) 구조의 태양전지 모듈 효율이 향상될 것이다. 본 논문에서는 요철(anti-glare) 구조를 만들기 위해서 유리와 평면 구조의 유리에서의 반사율과 투과율을 측정하여 비교 분석하였고, 특히 태양고도의 고도가 변할 때를 비교하기 위하여 반사율 및 투과율을 측정 할 때 입사광의 각도를 변화시켰다. 그리고 태양전지 cell 위에 요철(anti-glare) 구조의 유리와 평명 구조의 유리를 각각 위치시킨 후 태양전지 cell의 효율변화를 확인하였다. 이때 태양전지 cell의 표면은 이방성 식각 용액을 이용하여 역피라미드 구조의 텍스쳐링 태양전지 cell과 평면 구조의 태양전지 cell을 각각 사용하여 비교하였다.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.616-619
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• 2009

국내 육성 품종 JW07-190, JW07-192과 일본산 도입 품종 Meiryoku (MR), Ryoufuu (RF), Yamanoibuki (YI) 대해서 80% 메탄올 추출물을 공시 재료로 ESR을 이용하여 항산화 효능을 평가하였다. 국내 육성 품종인 JW07-192에서 DPPH radical, alkyl radical, hydroxyl radical에 대해 비교적 높은 radical 소거능을 보였고, 모든 녹차 품종에서 강력한 DPPH radical 소거능을 보였다. 전체적으로, 국내 육성 품종인 JW07-192가 일본 도입 품종과 비교하였을 때 더 좋은 항산화 효능을 나타내었다. 총 폴리페놀 함량은 국내 육성 계통인 JW07-192가 $431.57{\pm}28.45\;mg/g$로 가장 높은 함량을 나타냈고, 플라보노이드 함량은 도입 품종인 YI가 $313.44{\pm}6.31$로 가장 높은 함량을 보였다.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.190-195
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• 2006

The purpose of this study was to figure out the best condition in growth and sod quality of Mentha spp. according to cutting methods and soil depth. Applemint (M. suaveolens), Peppermint (M. piperita), and Spearmint (M. spicata) were used. Regardless of cultivar and soil depth condition, the growth rate in top cutting was higher than layering method. The difference between layering and layering without apical meristem was not significant. Optimal condition for growth was 5cm depth of soil. However, the shallower the depth of the soil, the better quality of sod. Among three Mentha species, M suavelens showed plant height and node number and M. piperita had shoot number were higher than other variety. The best condition of sod was top cutting and 1cm depth of soil regardless of cultivar.

• Membrane Journal
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• v.20 no.4
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• pp.320-325
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• 2010

This paper was carried out to study the preparation condition and the permeation flux of reinforced poly(vinylidene fluoride) (PVDF) hollow fiber microfiltration (MF) membrane with the solvent, additive, second miscible polymer, and preparation condition used poly(vinylidene fluoride) (PVDF) such as a material with the excellent chemical stability and the milder preparation condition. The performance of the reinforced MF membrane prepared obtained the average $0.3{\mu}m$ pore size, $42kg_f/cm^2$ tensile strength, and the high water flux of 600 LMH. The change of membrane performance with various additives was considerably affected on the water flux and rejection. For hydrophilic modification of hydrophobic PVDF MF membrane, the MF membrane might be prepared with a prefer water flux and rejection by addition of hydrophilic poly(methyl methacrylate) (PMMA).

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.223-235
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• 2010

As the funeral service is on ritual of addressing death that is the final phase of life, it can be said to be the final stage of welfare service. It is developing into the stage of make-up, which reproduces the image of reality or expresses with the better appearance from the level of recovery technique, which restores the final form of the dead. This is caused by a request of the bereaved family with the aim of remembering the dead's final image with good looks. Methods, which are being changed by period, can be found in a record. As this funeral make-up is one field of special make-up, it is systematically made into proper application method along with the development in special materials. Thus, it will become one of the most important courses henceforth in our funeral culture available for beautifully decorating the dead's final image. In order to satisfy the request of the bereaved family, it is necessary to made floral decoration, casket cloth, and acoustic effect including the casket stage of worshipping the dead inside the funeral hall.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.622-633
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• 2014

This study delineates the process of analyzing the illustrations in high school English I textbook. The goal of this study is to shed light on the issues related to producing better English textbooks. The methods include analysis of the illustrations in the textbook developed under the 2009 Revised National Curriculum and surveys of teachers and students' awareness about them. This study classified common features in the illustrations to devise four analysis criteria: cultural aspects, expression styles, expression techniques, and linguistic functions of the illustrations. The questionnaire was made for both teachers and students. The questions in the survey of teachers were about the relevance to the contents, the layout and formation, learners' interest, cognitive aspects, easiness of teaching and learning, and connectivity with language functions. In the survey of students, familiarity, interest level, learnability, favored expression technique and expression material were considered. The result of the surveys showed that the teachability and learnability are key factors in developing illustrations for English textbooks, and they should look familiar to the students.