• Journal of the Korean Applied Science and Technology
• /
• v.37 no.5
• /
• pp.1159-1170
• /
• 2020

In this study, to improve the stability of fermented squalene developed using microorganisms, Microsome-SQ20 was prepared, and its physical behavior, properties, and efficacy were studied. The appearance of Microsome-SQ20 was a transparent liquid, no smell, and had a specific smell. The color was a transparent liquid, and the specific gravity was 0.928 and the pH was 5.82 (20% solution), forming a nano-emulsion suitable for use in cosmetics. It was confirmed that the content of the main component of squalene was 20.05%, which was stably sealed. The particle size measured by 0.1% aqueous solution of Microsome-SQ20 was 134.8 nm to obtain a bluish emulsified phase. The antioxidant effects of F-SQ and MF-SQ by DPPH radicals were 80.72% and 81.5%, respectively, showing superior effects compared to L-ascorbic acid. The cell viability of squalene (SQ), fermented squalene (F-SQ) and microsome squalene (MF-SQ) was at 10 ppm, respectively, showing 121.2%, 150.3%, and 129.9% cell viability. It was found that SQ, F-SQ, and MF-SQ had an elastase inhibitory ability of 8.7%, 10.33% and 8.7% at 10 ppm, respectively. In addition, the inhibitory ability of MMP-1 was 1.55%, 41.44%, 31.79% at 10 ppm for SQ, F-SQ, and MF-SQ, respectively, indicating that F-SQ significantly reduced the MMP-1 expression.

• Journal of Nutrition and Health
• /
• v.23 no.6
• /
• pp.434-442
• /
• 1990

A new HPLC method for determining malonaldehyde content in lipid peroxidation systems was developed and antioxidant activities of $\alpha$-, $\beta$- carotene, lutein and lycopene were compared by a newly developed HPLC analysis and by TBA value. In addition, malonaldehyde forming ability of rat liver microsome was determined depending on thawing numbers. As results, malonaldehyde was eluted at a retention o f5.60 min and showed a linear relationship between peak area and concentration in standard curve. The MA content of microsome decreased with thawing numbers possible by destruction of cellular membranes. Lycopene, lutein and $\alpha$-carotene showed stronger antioxidant activities than $\beta$-carotene of DL-$\alpha$-tocopherol both in Fe+3-ADP/NADPH and in paraquat/NADPH system. The inhibitory effects of carotenoids and DL-$\alpha$-tocopherol on Fe+3-ADP/NADPH lipid peroxidation system was similar by TBA value and by the HPLC analysis for malonaldehyde.

• Korean journal of food and cookery science
• /
• v.11 no.4
• /
• pp.365-369
• /
• 1995

The content ratios of gingerol in 4 fractions (hexane, ether, ethylacetate and hexane-ether (1:1, v/v) fraction) extracted from ginger (Zingiber officinale Roscoe) were analyzed using high performance liquid chromatography (HPLC). The content ratios of 6-gingerol in 4 fractions were hexane fraction; 49.5％, ether fraction; 20.74％, ethylacetate fraction; 21.43％ and hexane-ether (1 : 1, v/v) fraction; 93.70％. Antioxidant activities of soybean oil added 0.2％ of each ginger fraction and 0.02％ of BHT were determined by peroxide value during storage at 45$^{\circ}C$. And relative antioxidant effectiveness (RAE) was calculated as the ratio of the induction period of a given substrate oil to that of a control oil. RAE of each fraction was hexane fraction; 2.60, ether fraction; 2.33, ethylacetate fraction; 2.07 and hexane-ether (1 : 1, v/v) fraction; 2.75, BHT; 1.74. Inhibition effect of each fraction on the rat liver microsomal lipid peroxidation showed hexane fraction; 93％, ether fraction; 92％, ethylacetate fraction; 86％ in 350 g/$m\ell$ and hexane-ether (1 : 1, v/v) fraction; 89％ in 20 g/$m\ell$.

• Journal of Life Science
• /
• v.8 no.6
• /
• pp.695-701
• /
• 1998

This study was carried out to investigate levels of the components of microsomal mixed function oxidase (MFO) system and activities of the hepatic microsomal cytochrome P45O (P45O)-dependent monooxygenases of grass snake (Natrix tigrina Lateralis) and to compare with those of rat. The levels of P45O and cytochrome b$_{5}$, (b$_{5}$) of snake were much lower than those in rat. NADPH-cytochrome c reductase activity in the snake was also only 40% of that in the rat. Activities of 7-ethoxycoumarin 0-deethylase (ECOD) and benzphetamine N-demethylase (BPDM) of snake hepatic microsomes, when compared with those of rat, were markedly low. But, aryl hydrocarbon hydroxylase (AHH) and testosterone hydroxylase (TSH) activities were nearly the same or higher than those of the rat. Of the P45O-dependent TSHs measured, 7$\alpha$-hydroxylase activity was the highest in snake, whereas, 6$\beta$-hydroxylase activity was the highest in rat. However, stereoselectivity of the enzyme from the snake to C2 and C6 positions of testoste-rone was the same as rat. The result of radioimmunoassay (RIA) for the identification of five P45O isozymes with MAbs shows that relatively high content of ethanol-inducible P45O isozyme, CYP2El, exists in the rat, whereas MC-inducible P45O isozyme, CYP2A1/1A2, does in the snake. From the analyses of SDS-PAGE and RIA of partially pu-rified P45O, we suggest the possibility of the presence of a certain P45O isozyme(s) in hepatic microsomes of snake different from those of rat.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2000.10b
• /
• pp.1223-1226
• /
• 2000

향후 IMT2000 에서도 사용가능한 자바 플랫폼을 기반으로 하는 마이크로브라우저를 설계하기 위해서는 썬마이크로시스템즈에서 제공하는 J2ME 의 기술인 CLDC 와 이를 좀 더 구체적으로 하는 MIDP 를 이용해서 플랫폼을 설계한다. 그리고 무선 인터넷 환경에 적합한 WAP를 마이크로브라우저로 사용한다. MIDP를 사용하기 위해서는 JAM을 이용해 애플리케이션을 관리할 수 있다.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2000.11a
• /
• pp.385-388
• /
• 2000

본 논문에서는 좀더 효율적이고 소형화한 GPS(Global Positioning System)용 안테나와 LNA(Low Noise Amplifier)를 IMT-2000 단말기에 내장함으로써 개인 휴대 통신 기능과 더불어 좀 더 정확한 위치추적 기능을 동시에 가능케 하고자 한다. 중심 주파수 1.575 GHz의 저잡음 증폭기와 안테나의 크기는, 합쳐서 10$\times$10$\times$4 (mm)로서 상층은 마이크로스트립 패치 안테나이고, 중간층은 안테나 ground와 LNA ground의 공통 ground이며, 제일 아래층에는 LNA가 위치하게 된다. LNA 의 경우 2단을 중첩하여, 첫째 단 16dB, 둘째 단 18dB의 이득 특성을 보였는데 첫째, 둘째 단의 대역통과 필터에서 삽입손실로 3dB의 손실을 가져와 총 3dB의 이득 특성을 보였다. 잡음 특성은 약 1.9의 특성을 보였다. 안테나의 경우 9$\times$9$\times$$\times$2 (mm)로써, 고유전율( $\varepsilon$$_{r}$ = 73 )의 세라믹을 사용하여 그 크기를 상당부분 줄였다. 그리고 유전체 밑의 ground를 옆면까지 높임으로써 좀 더 소형화한 안테나를 가능케 하였다. 고유전율의 유전체를 사용하였기에 안테나 자체의 이득 특성은 저잡음 증폭기에서 보상하고, 안테나의 임피던스 정합 또한 LNA의 입력 쪽에서 하도록 하였다. 또한 위성신호 수신을 위해 안테나는 RHCP 의 원형편파 특성을 갖는다.

• 한국정보교육학회:학술대회논문집
• /
• 2005.08a
• /
• pp.173-182
• /
• 2005

세계는 국가의 발전과 문명의 발전이 첨단 기술 개발에 달려 있다는 것을 알고 남들 보다 좀 더 새롭고 강력한 기술을 개발하기 위하여 박차를 가하고 있다. 또한 이러한 첨단 기술을 확보하기 위하여 많은 국가와 기업은 막대한 자본을 투자하고 있으며 교육에서도 예외는 아닐 것이다. 이러한 환경에 변화에 맞추어 첨단 과학의 미래를 이끌어 나갈 인재 육성이 더욱 필요하다고 할 수 있을 것이다. 단순히 공작 활동에서 벗어나 스스로 창의적인 생각하고 조작할 수 있는 공학적인 마인드를 갖는 인재 육성이 필요 되어지고 있다. 이러한 시대적인 요구에 부흥하는 마이크로 로봇 제작은 창의력 개발과 동시에 전자와 기계를 동시에 익히며 배울 수 있는 적절한 대안이 될 것이다. 따라서 본 연구는 초등학교에서 마이크로 로봇을 제작 방법과 그 교육적 활용 방안에 대하여 연구하여 보았다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2000.10b
• /
• pp.1067-1070
• /
• 2000

WAP(Wireless Application Protocol)을 기반으로 한 무선 인터넷 분야의 발전과 더불어 엄청나게 늘어난 무선 인터넷 이용자들의 컨텐츠에 대한 요구가 다양해지고 있다. 따라서 CP(Content Provider)들은 무선 장비에 맞게 설계된 WML(Wireless Markup Language)과 WMLScipt를 무선 장비를 사용하지 않고, 실제와 비슷한 상황에서 컨텐츠(Content)를 개발할 수 있는 환경이 필요하게 되었다. 본 논문에서는 무선 웹 컨텐츠를 좀 더 쉽게 개발할 수 있도록 도와주는 WML 마이크로 브라우저의 구현에 대해 기술한다. WML 마이크로 브라우저는 WML 파싱(parsing) 모듈과 브라우징(Browsing)모들로 구성되고. 클라이언트 측 WAP 스택으로 요청한 결과로 얻은 컨텐츠를 화면에 출력한다.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.39 no.4
• /
• pp.301-307
• /
• 2015

The diameter of a proton beam emanating from the MC-50 cyclotron is about 2-3 mm with Gaussian distribution. This widely irradiated proton beam is not suitable for semiconductor etching, precise positioning, and micromachining, which require a small spot. In this study, a beam cutting method using a microhole is proposed as an economical alternative. We produced a microhole with aspect ratio, average diameter, and thickness of 428, $21{\mu}m$, and 9 mm, respectively, for cutting the proton beam. By using this high-aspect-ratio microhole, we conducted machinability tests on microstructures with sizes of tens of ${\mu}m$. Additionally, the results of simulation using GEANT4 and those of the actual experiment were compared and analyzed. The outcome confirmed the possibility of implementing a micro process technology for the fabrication of three-dimensional microstructures of 20 micron units using the MC-50 cyclotron with the microhole.

• Journal of Digital Convergence
• /
• v.12 no.12
• /
• pp.161-172
• /
• 2014

While innovative information technologies have been adopted quickly into our daily life, we often experience the discontinuance after being temporarily adopted. This paper aims to study the factors influencing discontinuance on Microblog to Chinese users who already temporarily adopted it. According to empirical analysis, complexity and security show up their influences into all perceived risks, and inconvenience innovation and subjective norm just effect social risks. And perceived risk shows influences in every reasons for discontinuance, especially lots influences come from complexity. So according to these results, it is needed that the complexity of Microblog should be reduced.