• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.328-334
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• 2007

Chemical heat pump system of 2-propanol/acetone/hydrogen is most suitable to the recovery of waste heat of power plant. various types of 5 wt% Pt-alumina catalysts were prepared for 2-propanol dehydrogenation using sol-gel method. The characteristics and the dehydrogenation reaction rate of each catalyst were investigated. Pt-alumina xerogel catalyst has excellent reaction rate and good durability in comparison with the existing alumina supported Pt catalysts. Pt-alumina aerogel catalyst had the highest reaction rate in all prepared catalysts, but sufficient aging time was necessary to maintain its reaction rate. A potential advantage of the aerogel catalyst is the fact that the high temperature heat treatment is not required. Without heat treatment or with low temperature heat treatment, the Pt-alumina aerogel catalyst has excellent reaction rate as well as durability and this gives us the economic advantage. Alumina xerogel supported Pt catalyst prepared by incipient wetness method showed good reaction rate, and had good mechanical strength. Blank alumina xerogel prepared by sol-gel method can be used for the support of metal catalysts.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.33-40
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• 2012

This study was carried out to investigate the effect of the addition of lotus (Nelumbo nucifera) root and leaf powder on the quality characteristics of pork patties. The pork patties were of four types: nothing added (CTL), 0.5% lotus root powder added (LRP), 0.25% lotus root and 0.25% lotus leaf powder added (LRLP), and 0.5% lotus leaf powder added (LLP). There was no significant difference in $L^*$ value (whiteness), cohesiveness, gumminess, chewiness, water holding capacity, VBN content, and total bacterial amount. The moisture was highest in CTL, protein was highest in LRLP, fat was highest in LRLP and LLP, and ash was highest in LRLP (p<0.05). The total polyphenol content of the CTL, LRP, LRLP, and LLP were 3.34, 3.64, 3.90 and 3.90 mg/100 g, respectively. The $a^*$ value was highest in CTL, and the $b^*$ value of LRLP and LLP were higher than those of CTL and LRP (p<0.05). The hardness of CTL and LRP were higher than those of LRLP and LLP, and springiness was lowest in LLP (p<0.05). The cooking loss, thickness change, diameter changes, and pH were highest in CTL (p<0.05). The TBARS was highest in CTL, and was lowest in LLP (p<0.05).

• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.234-243
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• 1992

Fatigue crack initiation life has a wide scatter and this makes the fatigue design of structural members difficult. In order to make the fatigue life distribution clear, it is required to prepare a large number of specimens and repeat the fatigue tests under the same loading condition. Such fatigue tests usually take much time and cost. In this study, a fatigue testing method using a multi-notched test specimen for the purpose of estimating the distribution function of fatigue crack initiation life by small number of fatigue tests is used. The purpose of this study is to verify the above fatigue testing method of a multi-notched specimen by using Bayesian reliability analysis, Least square method and Skewness method for the determination of unknown Weibull parameters. The multi-notched specimen is a specimen in which several tens of statistically identical notches are prepared.

• Elastomers and Composites
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• v.39 no.2
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• pp.131-141
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• 2004

The recycling of waste XLPE(crosslinked polyethylene), which is a major source of scraps from high voltage power transmission cables, has been discussed. The waste XLPE scraps were ground into fine powder with various sizes from less than $100{\mu}m$ up to about $1000{\mu}m$ using two types of tailor-made pulverizers. The compounds were prepared in a modular intermeshing co-rotating twin screw extruder at various conditions such as different compositions, types and powder sizes of waste XLPE, screw configurations and various polymer matrices (LDPE, HDPE, PP, PS). The mechanical and rheological properties and the fracture surface or the compounds were investigated. It was found that an improved impact strength was obtained from the compound with white XLPE powder pulverized from the scraps without outer/inner semi-conductive layers. Generally, the impact strength increases with the content of XLPE but decreases with the size of XLPE. Especially for LDPE, the extrusion was possible up to 80 wt% loading of XLPE. Also, the impact strength increases with the number of kneading disc blocks in the given screw configurations. The melt viscosity of the compounds increases with increasing XLPE loading. However, the higher shear thinning behavior of the compounds at common shear rates implies proper processibility of the compounds. In addition, the impact strength for other polymer matrices used increases with XLPE and it is noticeable that the impact strength of PS/XLPE (80/20 wt%) compound was improved twice that of pure PS.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.76-86
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• 2013

This study was performed to investigate the quality characteristics of gruel added with ramie leaves. For this study, ramie leaves were made into powder, which consists of 5.37% of moisture content, 27.10% of crude protein, 5.99% of crude lipid, 47.17% of carbohydrate, 14.37% of crude ash. The gruel was prepared with rice powder, salt, and various levels (0, 2, 4, 6, 8%) of ramie powder. After making the gruel, it was examined for the effect of adding ramie on quality characteristics using a mechanical test and a sensory evaluation. The solid contents of gruel tended to decrease with increased amounts of ramie powder. As the amount of ramie powder increased, there were several changes in the sample groups as follows. The pH increased, and the lightness(L) and redness(a) decreased, while yellowness(b) increased; the viscosity decreased, whereas spreadability increased gradually. The results of the sensory evaluation showed that overall-acceptability had the highest scores in the gruel containing 6% level of ramie. In conclusion, the gruel added with 6% of ramie is the best in quality and acceptability.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.831-841
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• 2010

The conventional vertical probe has the thin and long signal path that makes transfer characteristic of probe worse because of the S-shaped structure. So we propose the new vertical probe structure that has branch springs in the S-shaped probe. It makes closed loop when the probe mechanically connects to the electrode on a wafer. We fabricated the proposed vertical probe and measured the transfer characteristic and mechanical properties. Compared to the conventional S-shaped vertical probe, the proposed probe has the overdrive that is 1.2 times larger and the contact force that is 2.5 times larger. And we got the improved transfer characteristic by 1.4 dB in $0{\sim}10$ GHz. Also we developed the simulation model of the probe card by using full-wave simulator and the simulation result is correlated with measurement one. As a result of this simulation model, the cantilever probe and PCB have the worst transfer characteristic in the probe card.

• Journal of the Korean Home Economics Association
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• v.38 no.12
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• pp.257-269
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• 2000

예술작품은 의상디자인에 영감 혹은 영향을 줌으로써 상업적 의상으로 재생산된다. 오늘날까지도 60년대의 많은 팝 아티스트 작품들이 그대로 T셔츠 등에 프린트되는 것을 쉽게 볼 수 있다. 이러한 직접적 영향에는 자주 맹목적 표절이라는 논란을 불러 일으켰으나 긍정적이든 부정적이든 예술작품과 의상 디자인은 20세기초부터 밀접한 관계를 가져왔다. Sonia Delaunay는 예술을 대중과 결합시키는 가장 좋은 방법은 의상을 통해서라고 생각하였다. 그녀는 "만일 예술작품을 생활 속에 들어가게 하려면 그건 여성들 자신이 입고 다니는 방법뿐이다". 라고 말하였다. 결국 이러한 예술의 대중화에 대한 이론은 60년대에 와서 팝 아트 패션의 출현으로 그 결실을 보게 된다. 상류층을 대상으로 한 의상이 대중화되는 과정에서 60년대 경제호황으로 인한 젊은이들의 소비자층 형성과 미술양식에서의 팝아트의 출현은 자연스러운 시대적 조류로 나타났다. 이러한 상황은 팝 아트가 이 시대의 미술 양식에 혁신적일 뿐 아니라, 사회 전반에 팝 아트의 특성(소비 문화적, 대중 문화적, 재현적, 통속적, 기계적, 획일적)을 유행시키고, 대중에게 순수 예술과 복식에 참여 할 수 있는 기회를 부여했다고 볼 수 있다. 따라서 본 연구에서는 가장 혁명적이고도 대중적이라고 할 수 있는 팝 아트 이미지의 작품 제작과 분석을 통하여 현재 논의되고 있는 전시회나 패션쇼에서만 볼 수 있다는 다소 아방가르드 적인 의상 작품들의 대중화 방안에 대한 해결책을 모색하고자 하였다. 실제 의상 디자인 창작에 초점을 맞추었으며, 제작을 위해서 팝 아트에서 주요 소재로 삼았고 대중적 이미지의 심볼이라고도 할 수 있는 Coca Cola label을 표현 모티브로 삼아 개성적이고도 독창적인 의상 디자인을 한 후 분석하였다. 또한 독특한 의상 표현의 개발을 위하여 표현 기법으로는 현대 미술에서 새로운 재료와 여러 가지 재료를 화면에 도입시키는 표현 방법으로서 사용된 콜라주 기법을 사용하였다. 본 연구를 통하여 의상 창작에 있어 조형예술과 연결하여 대중적인 이미지를 도입함으로써 착용자가 예술에 대한 친근하고 익숙한 느낌을 갖게 하며, 예술과 상품 그 자체에 대한 상업적 홍보 목적으로도 사용할 수 있으며, 대중적인 이미지를 표현함에 있어 콜라주 기법은 염색 기법을 사용하지 않고서도 작가가 원하는 표현 효과를 낼 수 있다는 측면을 발견할 수 있었다. 즉 사용된 대중적 상표 이미지는 주인에서 흔히 볼 수 있는 현대 도시의 인공적 환경들로, 의상을 독특하고 개성 있게 표현할 수 있는 모티브의 역할을 하면서 또한 그 예가 무한하여 다양한 디자인 창출의 가능성을 갖고 있으며, 의상을 통해 예술과 대중을 융합시켰다는 예술의 대중화, 민주화라는 중요한 역할을 하였다. 전시회나 패션쇼에서 만 볼 수 있는 예술적 성격을 띠는 아방가르드 작품의 대중 확산 방법으로 제시될 수 있는 이상적인 방법으로는 예술성이 짙은 도저히 입을 수 없다고 생각되어지는 아방가르드한 의상을 일반 대중 브랜드들이 단순한 모방이 아닌 새로운 패러디 작업으로 일반화시켜 상업성을 띤 의상으로 재조정되어 여성들의 몸에 걸치게 하는 것이다. 이와 같은 순환으로써, 조형예술 작품은 의상 디자인 참작에 영향, 영감을 주면서 여러 번의 형태 변화를 거치는 패러디를 통해 각 계층의 누구나가 좋아하고 접할 수 있는 또 다른 창조를 맞아 대중의 손까지 갈 수 있는 것이다.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.69-76
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• 2009

This study was conducted to evaluate the physicochemical and sensory characteristics of chiffon cakes made with rice flour ranging from 20-100% in place of wheat flour. The water binding capacity of the rice flour was greater than that of the wheat flour and its fat binding capacity was lower than that of the wheat flour. The batter stability data indicated that the 100% treatment was better than the control, and specific gravity values and specific loaf volumes were lower in the samples with added rice flour. Texture analysis found no significant differences in hardness, adhesiveness, cohesiveness, gumminess, and chewiness between the control and the 100% treatment. In the case of crust color, the rice flour-added chiffon cakes did not show any significant differences for their 'a' values. In addition, their crumb color was not significantly different in terms of both their 'L' and 'a' values. According to the sensory evaluation, there was no significant difference in overall acceptability between the control and the rice flour-added chiffon cakes. The highest sensory scores were obtained by the 100% treatment for overall acceptance and moistness. However, flavor, cohesiveness, and brittleness were not significantly different. These study results show that wheat flour could be replaced by rice flour up to 100% in chiffon cake.

• 대한공업교육학회지
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• v.39 no.1
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• pp.247-261
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• 2014

Education about invention in elementary schools has thus far be conducted mostly through special activities and talented activities rather than through normal curricula. However, with the implementation of the 2007 amended curricula, invention education was reflected as a normal subject unit in the practical subject (technology and home economics) curricula, thereby laying groundwork for invention education being able to be provided through normal subject classes. Thus, at the time when invention education has been reflected as a normal subject unit, it is meaningful to research the effects of elementary school students' experience in invention education on their invention attitudes. This study sought to research the effects of elementary school students' experience or non-experience in invention education on their invention attitudes, targeting those in regional talent private schools who did not take invention talent classes, those who received invention education, and those who did not receive invention education at all. The conclusion of this study is outlined as follows. First, students' experience in invention education proved to be positive in boosting their invention attitude, and continued invention education experience like with students in regional talent invention schools significantly boosted their invention attitudes. Second, considering that students' actual experience in invention education had positive effects on their invention attitudes, the reflection of invention education in the amended curricula was found to be very desirable in improving elementary students' attitudes about invention. Third, according to gender, male students' invention attitude level was found to be higher than that of female students, suggesting that male students more worked on computers, electronic (smart) devices and machines in daily life, leading them to further develop invention attitudes.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.219-226
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• 2020

Over the last decades, great efforts have been devoted to reuse industrial wastes and by-products from various industries as supplementary cementitious materials in order to reduce carbon dioxide(CO₂) emission by reducing the use of Portland cement in construction. Oyster shell waste, originating from the fishery industry, is available in huge quantities in certain areas, and is generally discarded or landfilled. In this study, we aimed to reuse oyster shell as an alternative to limestone in limestone calcined clay cement(LC³). The oyster shell calcined clay cement(OC³) paste were produced and were characterized via X-ray diffraction, isothermal calorimetry, compressive strength tests, and thermogravimetry. The results revealed that OC³ pastes exhibited similar strength development and reactivities by pozzolanic reaction with LC³, which implies that oyster shell could be used as a substitute for limestone in LC³.