• Resources Recycling
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• v.17 no.2
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• pp.36-45
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• 2008

Pickling of oxidized 304 stainless steel has been investigated using rotating disk electrode in waste acid solutions generated from the etching process of silicon wafer in order to recycle them. The waste acid solution contained acetic, nitric, hydrofluoric acids, and silicon of $19.6g/L^{-1}$. Electrochemical behavior during the pickling was distinctively different between the original and silicon-removed acid solutions. Open circuit potential was continuously changed in the original solution, while it was discontinuously changed and fluctuated in the silicon-removed solution. Fast and abrupt removal of surface oxide layer with severe pitting was observed in the silicon-removed solution. It was found that solution temperature had the most influential effect on glossiness. Surface glossiness after pickling was decreased with solution temperature. At the same condition, the glossiness was higher in the original solution than in the silicon-removed solution.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.694-701
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• 2014

This study aimed to investigate the aging of liquor brewed with fermented wine using ipguk (koji) in a jar (JA) and stainless steel container (SC), which are generally used in Korea, and to review the characteristics of the liquors as a function of aging time. The initial alcohol content was 39.8-40.9%, and gradually decreased in the JA and SC as the aging time increased. In the case of fusel alcohols, the n-propanol, isobutanol, and isoamyl alcohol contents did not increase with increasing aging time, in the cases of both JA and SC. The A/B (isoamyl alcohol/isobutyl alcohol) ratio was similar under reduced pressure (RP) and atmospheric pressure (AP), at 1.32-135. The A/P (isoamyl alcohol/n-propanol) and B/P (isobutyl alcohol/n-propanol) ratios were 2.17-2.22 and 1.62-1.68, respectively. During the early stages of distillation, under RP, the isoamyl alcohol content was the greatest, followed by isobutyl alcohol and ethyl palmitate. Under AP, the isoamyl alcohol content was the greatest followed by decanoic acid, ethyl palmitate, and isobutyl alcohol. The highest sensory score under RP, 60 cmHg, was $6.98{\pm}0.28$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.743-752
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• 2013

The objective of this study was to investigate the quality characteristics of spirits derived from fruit using copper distillation equipment. First, optimal yeast strains were chosen through a fermentation test on raw materials (apples, mandarins and rowanberries). The normal fermentation condition for rowanberries observed at a rowanberry concentration of 8% during mashing included chaptalization with sugar to increase the alcohol content. During the mashing, fruits were fermented and distilled through one of three different types of distillation apparatuses (pot distiller, vacuum distiller, or multistage distiller made of copper). The results revealed that the type of apparatus used affects the content of alcohol and flavor components. The distilled spirits prepared through a copper multistage distiller had a much higher tendency to retain components of fruit aromas such as ethyl acetate and provided higher yields than spirits prepared with a pot distiller or vacuum distiller. Thus, the copper multistage distiller apparatus can be applied to positively influence the taste and flavor of fruit distilled spirits by enhancing fruit aromas, removing impurities such as sulfur components and enhancing yields.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.1
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• pp.29-38
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• 2022

Recently, seismic design for anchors is required, which are used for connecting structural members and non-structural and structural members. In this study, pull-out tests on the new expansion anchors which have been developed for cracked concrete. The anchors of 12 mm and 20 mm diameters were tested which are commonly used. Experiments were conducted on non-cracked concrete and cracked concrete to evaluate the seismic performance of the post-installed anchor. The experimental method complies with the specified test protocol (KCI, 2018). Three experimental variables are included in this study: presence of cracks, concrete compressive strength, and effective embedment depth. The strength of the anchors was evaluated with the characteristic capacity K_5% determined from the test results incorporated with the safety of 5% fractile. The characteristic capacity K_5% of the non-cracked and cracked concrete specified in KDS 14 20 54 are 9.8 and 7.0, respectively. Test results show that all groups except the three groups have higher characteristic capacity K_5% than the KDS code and the nominal strengths of the tested anchors can be determined with the obtained characteristic capacity K_5%.

• Science of Emotion and Sensibility
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• v.25 no.2
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• pp.23-30
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• 2022

The weight of an object is an important research topic in terms of sense, and objects have size-weight, color-weight, and material-weight illusions due to the influence of size, color, and material and the weight of the object. Although temperature is a very important environmental factor in our daily life, there is a dearth of studies on how the temperature of an object affects its perceived weight. This study analyzed the effect of an object's temperature on the perceived weight. A stainless steel cup, in which weight and temperature are easily adjustable, was selected as a perceived weight measurement object; 5 temperature levels (0, 9, 20, 40, 70 degrees) and 2 weight levels (250, 400 g) were set. A total of 40 healthy men and women in their 20s participated in the experiment. The weight of the given cup compared to the reference cup was evaluated according to the modulus method. The study revealed that both temperature and weight significantly affected the perceived weight. The effect of temperature on the weight was different depending on the weight of the object. When the cup's weight was small (250 g), the temperature of the cup did not affect the weight. However, the perceived weight of a large cup (400 g) increased at a low temperature. This result suggests that the effect of temperature on the weight of an object depends on the size-weight illusion.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.723-724
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• 2012

• 월간 기계설비
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• s.294
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• pp.128-130
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• 2015

한국의 제조, 공업, 건설시장의 성장에 따라 국내 펌프 수요도 날이 갈수록 늘고 있다. 이에 대한 수요에 대응하여 펌프전문기업인 한일펌프는 창립 50주년을 맞아 에너지 절감형 개별인버터 펌프 신제품인 쿨런트 펌프를 선보였으며, ALL스테인레스 환풍기 및 송풍기 외 양흡입 송풍기 인라인휀 포터블팬 등 다양한 풍력 제품들도 출시했다. 한일전기는 녹 발생이 없는 ALL스테인리스 펌프를 비롯해 현장 수요에 맞춰 필요 부품의 생산부터 조립 테스트 등 부스터 및 산업용 펌프 24시간 제품 출고 시스템을 구축하는 등 차별화된 서비스를 제공하고 있다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.6
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• pp.1183-1192
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• 1989

본 논문에서는 평면변형률 상태하에서 안정하게 성장하는 균열선단에 집중 되어있는 강소성역의 해석에 역점을 두어 재결정법과 탄.소성유한요소법을 도입하여 안정 성장균열 선단에 형성되는 균열 성장저항에 직접적인 영향을 미치고 있는 소성 역의 크기나 형태에 대한 실험 및 해석을 하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.31-32
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• 2006

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.107-108
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• 2009

This study is focused on the thickness change in burring with stainless 409L according to the change of main design variables and forming conditions, to manufacture the automobile exhaust flange. Large plastic deformations by burring process decreases thickness of inner radius and occurs cracks. The optimal design of performs by the finite element analysis achieves adequate improvement of thickness decrease.