• Magazine of RCR
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• v.17 no.3
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• pp.50-53
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• 2022

• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.13-22
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• 1998

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.346.2-346
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• 1999

• Proceedings of the Korean Reliability Society Conference
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• 2002.06a
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• pp.147-155
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• 2002

본 연구에서는 옥외에서 사용하는 소재의 신뢰성 평가(내후성)에 관한 연구를 수행하였는데 국내와 일본의 옥외환경시험장에 시험편을 동시에 폭로하여 기상인자 및 주변환경에 따른 시험편의 특성 변화를 상호 비교ㆍ평가하였고 인공 촉진내후성 시험을 실시하여 옥외내후성과의 상관관계를 관찰하였으며 그 결과는 다음과 같다. 국내 지역의 옥외환경시험장 중에서는 인천 옥외환경시험장에 폭로한 시험편에서 가장 많은 변화를 나타내고 있으며, 일본 지역은 가혹한 기상환경을 나타내는 미야고지마 옥외환경시험장에 폭로한 시험편에서 많은 변화가 나타남을 관찰할 수 있었는데 국내 지역보다는 온도와 습도 등 기상제조건이 더 가혹한 일본 지역의 옥외환경시험장에 폭로한 시험편의 노화가 더 빠르게 진행됨을 관찰하였다.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.34-42
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• 2002

This research was carried out to investigate water repellent effectiveness of natural oil treated wood. Linseed oil, castor oil, olive oil, bean oil, perilla oil and sunflower oil were used in this test. For evaluation of water repellent of natural oil treated wood, moisture absorption test, water-drop contact angle test and color difference test of accelerated decomposition by UV and water were used. The moisture absorption amount of natural oil treated wood was less than untreated wood until 3 hours, but it was increased with time, there was no big difference with oil treated wood and untreated wood after 48hours. Oil treated wood and untreated wood showed big difference on contact angle test. It was no big difference by kind and oil concentration. Natural oil treated wood did not showed stability on the weather aging test. Contact angle test could be used on evaluation of wood surface status treated with natural oil.

• Food Science and Industry
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• v.53 no.4
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• pp.390-396
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• 2020

We investigated the anti-obesity effect of Gelidium elegans extract (GE) on 3T3-L1 preadipocytes and a high-fat-diet (HFD)-induced mouse model. The results of the present study demonstrated that GE prevents weight gain induced by a high-fat diet (HFD) by modulating the adenosine monophosphate-activated protein kinase (AMPK)-PR domain-containing 16 (PRDM16)-uncoupling protein-1 (UCP-1) pathway in a mice model. Moreover, in vitro results show that GE suppressed adipocyte differentiation by modulating adipogenic regulators, stimulated lipolysis by activating ATGL, and inhibited adipogenesis by downregulating various enzymes associated with triglyceride synthesis. GE was also found to upregulate AMPK phosphorylation as well as the expression of UCP1 and PRDM16 proteins, leading to measurable changes in the beige-like phenotype differentiation of 3T3-L1 cells. Taken together, these findings suggest the role of GE as a functional food ingredient extracted from Gelidium elegans to increase energy expenditure and anti-obesity efficacy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.67-75
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• 1993

This study was performed for the purpose of estimating steel corrosion and of considering a countermeasure to prevent steel corrosion of concrete structures under the environment of seawater or using seasand. The corrosion of steel was accelerated in artificial seawater with seven kinds of specimen which was embedded steel in mortar. To assume the degree of steel corrosion, soluble chloride content in mortar, $Cl^-$ binding capacity, half cell potential and corrosion area ratio were measured. The results show that corrosion area ratio was correlative with half cell potential and soluble chloride content in mortar.

• Journal of Ginseng Research
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• v.11 no.1
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• pp.77-83
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• 1987

The effects of ginseng saponin on the germination and early growth of rice seeds (Oryza sativa L.) were investigated. The early growth (length) of test rice seeds which were rinsed for 60 hrs in $10^{-4}$% saponin solution prior to transplantation to water agar bed was about 20% faster than that of control seeds, It was also found that the amylase activity of the seeds was most active when the seeds were rinsed in 10-4% saponin solution for 48 hrs. In vitro investigation showed that the amylase activities were stimulated about 30% by the treatment of $10^{-5}$% saponin solution compared with control group. From the above results, it seems that the ginseng saponin might activate amylase of rice seed during germination, resulting in rapid growth of rice.

• Journal of Ocean Engineering and Technology
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• v.19 no.6 s.67
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• pp.29-34
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• 2005

This paper describes the effect of fly ash replacement on seawater resistance of anti-washout underwater concrete, which was replaced cement by fly ash from $0\%$ to $50\%$. The experimental work was performed to find out the variations of length and weight of specimens, using a chloride acceleration test in $40\^{\circ}$C The results shaw that the admixture using fly ash on an anti-washcout underwater concrete in the sea environment makes it more durable for the attacks of chloride by seawater. Also, the length of specimens of anti-washout underwater concrete, at age 180 days, increased substantially, compared with normal concrete; however, the mixture in which cement was replaced $50\%$ of fly ash shows $93\%$ reduction of the expansion, compared with the normal anti "washout underwater concrete specimen.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.29 no.1
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• pp.27-44
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• 2003

전반적인 피부세포의 생리적 지능 자하로 인한 자연노화와 더불어, 여러 피부 스트레스 요인들이 다양하게 작용하여 발생하는 외인성노화를 방지하거나, 개선할 수 있는 항노화소재로서의 개발 가능성을 알아보기 위해, 예로부터 항염활성이 있다고 알려진 oleanolic acid(OA)를 포함한 ursolic acid(UA), betulin, betulinic acid(BA) 등의 triterpenoids가 어떻게 피부에서의 항노화 활성을 나타내는지를 알아보았다. 시험 결과, OA는 자외선에 의한 각질형성세포에서의 PGE$_2$ 생성과 섬유아세포(NHF)에 의한 matrix metalloproteinase-1(MMP-1) 분비를 억제하였다. 그리고, NHF의 procollagen 생성을 촉진하였으며, 이런 procollagen 생성촉진활성이 in vivo에서도 발현되는 것을 무모생쥐의 실험을 통해서 확인하였다. 또한 OA는 각질세포의 증식과 분화를 촉진하여 표피세포로 하여금 세라마이므와 필라그린 생성을 증가시키도록 하는 작용도 있음을 보여주었다. 더불어 실험한 UA, betulin, BA 들은 비록, betulin, BA의 경우 세포 독성이 다른 물질 들에 비해 높았고, UA가 각질세포의 분화를 오히려 억제하는 양상을 보이기는 했지만, 대부분의 기능은 OA와 유사하였다. 피부세포보호작용과 진피 기질물질에 대한 작용, 그리고, 표피의 장벽기능과 보습기능에 대해 시험한 본 연구는, 식물성분인 triterpenoids가 피부를 위한 항노화소재로서의 개발 가능성이 있음을 확인하는 계기가 되었고, 그 중에서도 OA가 보다 우수한 항노화 소재가 될 수 있음을 시사하고 있다.