• Title/Summary/Keyword: Hwang woo-suk

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Two Acylglycerylgalactosides and a New Sesquiterpene Galactoside from the Flowers of Hemisteptia lyrata Bunge

  • Ha, Tae-Joung;Lee, Jin-Hwan;Hwang, Seon-Woo;Lee, Jun;Kang, Nam-Suk;Park, Keum-Yong;Suh, Duck-Yong;Park, Ki-Hun;Yang, Min-Suk
    • Journal of Applied Biological Chemistry
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    • v.49 no.1
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    • pp.16-20
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    • 2006
  • The flowers of Hemisteptia lyrata B. afforded two known acylglycerylgalactosides, 2',3'-di-O-(9Z,12Z,15Z-octadecatrienoyl)glyceryl ${\beta}$-D-galactopyranoside (1) and 2'-O-(9Z,12Z,15Z-octadecatrienoyl)glyceryl ${\beta}$-D-galactopyranoside (2), and a new sesquiterpene galactopyranoside, 7-eudesmene-1${\beta}$,4${\beta}$-diol-1-O-${\beta}$-D-galactopyranoside (3). This is the first time that galactopyranosides (1-3) have been isolated from the genus Hemisteptia. Their structures and stereochemistry were elucidated by 1D and 2D NMR data, including COSY, NOESY and HMBC experiments.

Development of a Blended Corrosion, Scale and Micro-Organism Inhibitor for Open Recirculating Cooling System

  • Choi, Dong-Jin;You, Seung-Jae;Kim, Jung-Gu;Hwang, Woo-Suk
    • Corrosion Science and Technology
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    • v.4 no.3
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    • pp.89-94
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    • 2005
  • This paper presents the results of a study that was undertaken to optimize the ratio of the components of a new multi-component inhibitor blend composed of orthophosphate/ phosphonates/ acrylate copolymer/ isothiazolone. The effects of newly developed inhibitor on carbon steel dissolution in synthetic cooling water were studied through weight loss tests, electrochemical tests, scale tests, and micro-organism tests. The obtained results were compared to blank (uninhibited specimen) and showed that developed inhibitor revealed very good corrosion, scale, and micro-organism inhibition simultaneously. All measurements indicated that the efficiency of the blended mixture exceeded 90 %. The inhibitive effects arose from formation of protective films which might contain calcium phosphate, calcium phosphonate, and iron oxide. The nature of protective films formed on the carbon steel was studied by scanning electron microscopy (SEM) and auger electron spe ctroscopy (AES). Inhibitor used in this study appeared to have better performance for scale inhibition due to their superior crystal modification effect and excellent calcium carbonate scale inhibition properties. The effect of inhibitor on microorganisms was evaluated through minimum inhibitory concentration (MIC) test. All kinds of micro-organisms used in this study were inhibited under 78ppm concentration of inhibitor.

2$\beta$, 3$\alpha$, 23-trihydroxyrus-12-en-28-oic Acid Induces the Apoptosis of Human Colon Carcinoma HCT-1l6 Cells (2$\beta$, 3$\alpha$, 23-trihydroxyrus-12-en-28-oic acid 처리에 의한 인간 대장암 세포주 HCT-116의 apoptosis 유도)

  • Yoo, Ki-Hyun;HwangBo, Jeon;Lee, Ji-Hye;Seok, Yeon-Joo;Song, Myoung-Chong;Lee, Jong-Min;Baek, Nam-In;Kim, Soung-Hoon;Kim, Dae-Keun;Kown, Byoung-Mok;Park, Mi-Hyun;Chung, In-Sik
    • 한국약용작물학회:학술대회논문집
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    • 2007.05a
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    • pp.43-44
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    • 2007
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Thermal Performance Test of Liquid Cooling Type Cold Plates for Robot Cooling (로봇 냉각을 위한 수냉식 냉각판의 열적 성능 평가)

  • Karng, Sanrng-Woo;Lee, Suk-Won;Hwang, Kyu-Dae;Kim, Seo-Young
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.1864-1869
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    • 2007
  • In this study, we compare thermal performance between four different types of cold plates for humanoid robot cooling. Two commercially available cold plates made of copper have different dimensions and internal flow paths: One has $20{\times}20$ $mm^2$ base area with micro-channels and the other has $62.5{\times}62.5$ $mm^2$ base area with 85 round pin-fins. And two different types of cold plates of $20{\times}20$ $mm^2$ base area with 7 mm high are made of PC (polycarbonate), which aims to reduce the weight of cooling system. All cold plates are mounted on a $20{\times}20$ $mm^2$ copper block with two cartridge heaters of 30 $W/cm^2$. The overall heat transfer coefficient and thermal resistances for the liquid-cooled cold plates are obtained. The copper cold plate with micro-channels showed the best performance. Polycarbonate cold plates display fairly good thermal performance with more reduced system weight.

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Anticancer Effect of Thymol on AGS Human Gastric Carcinoma Cells

  • Kang, Seo-Hee;Kim, Yon-Suk;Kim, Eun-Kyung;Hwang, Jin-Woo;Jeong, Jae-Hyun;Dong, Xin;Lee, Jae-Woong;Moon, Sang-Ho;Jeon, Byong-Tae;Park, Pyo-Jam
    • Journal of Microbiology and Biotechnology
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    • v.26 no.1
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    • pp.28-37
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    • 2016
  • Numerous plants have been documented to contain phenolic compounds. Thymol is one among these phenolic compounds that possess a repertoire of pharmacological activities, including anti-inflammatory, anticancer, antioxidant, antibacterial, and antimicrobial effects. Despite of the plethora of affects elicited by thymol, its activity profile on gastric cancer cells is not explored. In this study, we discovered that thymol exerts anticancer effects by suppressing cell growth, inducing apoptosis, producing intracellular reactive oxygen species, depolarizing mitochondrial membrane potential, and activating the proapoptotic mitochondrial proteins Bax, cysteine aspartases (caspases), and poly ADP ribose polymerase in human gastric AGS cells. The outcomes of this study displayed that thymol, via an intrinsic mitochondrial pathway, was responsible for inducing apoptosis in gastric AGS cells. Hence, thymol might serve as a tentative agent in the future to treat cancer.

Single layer antireflection coating on PET substrates for display applications

  • Gowtham, M.;Mangalaraj, D.;Seo, Chang-Ki;Shim, Myung-Suk;Hwang, Sun-Woo;Yi, Jun-Sin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.988-991
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    • 2004
  • In the present investigation, we tried AR coating simulation by using the "Essential Macleod optical coating design and analysis" program. After various run of the program we selected appropriate materials which have specific refractive indices and for that thickness was optimized to get the low reflectance. By comparing the simulated results for the different materials,we found that $SiO_2$ and TiN are the appropriate materials for this Flat panel device (FPD) application. Thin films of these materials were deposited using RF magnetron sputtering and Inductively Coupled Plasma Chemical Vapour Deposition (ICPCVD) methods on Polyethyleneterephthalate (PET) substrates. Spectroscopic ellipsometer (SE MF-1000) and UV-Vis spectrophotometer (SCINCO) were used for the optical characterization. The obtained experimental results are in good agreement with the simulation results.

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The Study of Bus Information System's Efficiency (버스정보시스템의 효율성에 관한 연구)

  • Lee, Jeong-Keun;Choi, Suk-Woo;Hwang, Beyung-Ok
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.5 no.3 s.11
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    • pp.1-12
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    • 2006
  • Nowdays ITS is being installed in each local autonomous entity, and BIS installation and operation is prior to other ITS sub systems for the public service. The methods of positioning md wireless communication in BIS are DSRC+DSRC, GPS+wireless communication, Beacon+Beacon, which are chosen and operated as the local features. Before this study, the before and after survey of BIS' quality have only been done without performance evaluation of BIS. So the method of BIS' evaluation have been established including performance test in this paper. And the evaluation of some BIS' reliability and efficiency have been done using the reliability of arriving data and the wireless communication response rates after choosing typical BIS' sub system.

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A Study on Probabilistic Response-time Analysis for Real-time Control Systems (실시간 제어시스템의 확률적 응답시간 해석에 관한 연구)

  • Han, Jae-Hyun;Shin, Min-Suk;Hwang, In-Yong;SunWoo, Myoung-Ho
    • Transactions of the Korean Society of Automotive Engineers
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    • v.14 no.3
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    • pp.186-195
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    • 2006
  • In real-time control systems, the traditional timing analysis based on worst-case response-time(WCRT) is too conservative for the firm and soft real-time control systems, which permit the maximum utilization factor greater than one. We suggested a probabilistic analysis method possible to apply the firm and soft real-time control systems under considering dependency relationship between tasks. The proposed technique determines the deadline miss probability(DMP) of each task from computing the average response-time distribution under a fixed-priority scheduling policy. The method improves the predictable ability forthe average performance and the temporal behavior of real-time control systems.

Studies on cryopreservation of nuclear transplanted mouse embryos (마우스 핵이식란의 동결에 관한 연구)

  • Lee, Byeong-chun;Jo, Choong-ho;Hwang, Woo-suk
    • Korean Journal of Veterinary Research
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    • v.33 no.1
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    • pp.171-178
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    • 1993
  • The present study was carried out to investigate the developmental potency to blastocyst after freezing and thawing of nuclear transplanted 2-cell embryos. The nuclei from 2-, 4- and 8-cell mouse embryos were transferred into enucleated 2-cell embryos, and the reconstituted embryos were submitted to direct current(DC) pulse at output voltage of 2.0 kV/cm for $100{\mu}$ sec to induce cell fusion. The recovery rate and developmental potency to blastocyst after freezing and thawing of nuclear transplanted 2-cell embryos was investigated. 1. The recovery rate of nuclear transplanted 2-cell embryos in normal morphology after freezing and thawing was significantly higher in rapid freezing(DMSO 4.5M) than in slow cooling(p<0.01). 2. When the recovered embryos in normal morphology were cultured in vitro, there were no significant differences in the developmental potency to blastocyst between the freezing methods and the concentrations of cryoprotectant. In summary, these experiments have proved that rapid freezing method(DMSO 4.5M) is effective in nuclear transplanted 2-cell mouse embryos. If improved micromanipulation techniques and freezing are combined, nuclear transplantation technique will contribute to the improvement of productivity in livestock animals.

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Evaluation of conservation of endangered species through somatic cell nuclear technology (체세포복제를 통한 멸종위기동물의 종 보전 평가)

  • Hyun, Sang Hwan;Jeong, Yeon Woo;Hwang, Kyu Chan;Lee, Guk Jin;Yang, Il Suk
    • Korean Journal of Veterinary Research
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    • v.55 no.3
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    • pp.155-161
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    • 2015
  • The number of wild animal species is gradually decreasing due to poaching, hunting and habitat loss. While several endangered animal species have been successfully preserved at the zoo, assisted reproductive technology (ART) must be applied to restore wild animals. In the case of critically endangered animals, somatic cell cloning is considered the most appropriate method of ART. Somatic cell cloning can be beneficial for the reproduction of endangered species with limited female populations. However, gene and cell banks, and understanding of reproductive physiology and optimization of ART for wild animals are urgently required for further activation of artificial reproduction of endangered species, which enlarges its application and maintains biodiversity. Care should also be taken to consider ethical and legal issues associated with somatic cell cloning for conservation of endangered animals.