• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.1405-1408
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• 2005

이동성 관리 기술은 인터넷의 주요 접속 수단이 고정 접속 환경에서 이동 접속 환경으로 빠르게 변화함에 따라 그 중요성이 점차 커지고 있다. 특히 IP 기반의 차세대 유무선 통합망은 기지국마다 라우터가 구현되는 형태를 가정하고 있으므로 IP 를 기반으로 한 이동성 관리 기술의 제공은 필수적인 요소이다. 현재의 Mobile IP 는 빠른 이동성의 지원이 미약하여 차후 다양한 IP 멀티미디어 서비스 지원을 위한 신속한 핸드오버 시에는 많은 문제점을 가지고 있다. 따라서 본 논문에서는 SIP 를 기반으로 한 계층적 이동성 및 세션 관리 메커니즘에 대해서 제안한다. SIP 는 다양한 무선 액세스망에 상관없이 이동성 관리를 제공해 줄 수 있을 뿐만 아니라 세션 관리 기능까지 제공해 줄 수 있다. SIP 서버의 기능을 분산화 시킨 계층적 구조로서 이동성 및 세션 관리 기술을 제시하고 시뮬레이션을 통해 현재 제안된 이동성 관리 프로토콜인 Mobile IP 와의 비교를 함으로서 성능을 측정, 분석한다.

• Journal of Surface Science and Engineering
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• v.27 no.2
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• pp.99-108
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• 1994

Films of glass-ceramics $Li_2O-Al_2O_3-SiO_2$(LAS)system were prepared on substrate of an iron plate(SCP) by sol-gel technique using metal alkoxide such as Si$(OC_2H_5)_4$,Al$(OC_2H_9)_3$) and Ti$(OC_2H_6)_4$). Sol which was made by means of simple spray coating, on the substrate was hydrolyzed at 75~$80^{\circ}C$ in moisture cabinet (80~90 % humidity) to form the multicomponent gel. The films up to about 0.8~1.0$mu extrm{m}$ in thickness can be obtained by repeating operation, spraylongrightarrowhydrolysis and condensationlongrightarrowdryinglongrightarrowheating and crystallization at $700^{\circ}C$ for 3~5min. The far-infrared radiation spectra of the coated films on substrate were examined by FT-IR and of films was also observed by scanning electron micrograph technique. The thermal evaluation of the gel-film is followed by TG/DTA measurements. The structure evaluation is followedd X-ray diffraction. These results suggest that this process is applicable to far-infrared radiat at thin film technique.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.364-372
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• 1996

The primary skin and eye irritation test of 0.3% DA-5018 cream, a capsaicin analogue, were carried out in rabbits. As control materials, Zostrix-HP cream (0.075% capsaicin cream) and the base of 0.3% DA-5018 cream were used in the same manners. In the primary skin irritation test, the Primary Irritation Index (P.I.I.) was 1.6, 1.9 and 0.5 in groups treated with 0.3% DA-5018 cream, Zostrix-HP cream and the base of 0.3% DA-5018 cream, respectively. The irritation ratings of 0.3% DA-5018 cream and Zostrix-HP cream were mildly irritating. The base of 0.3% DA-5018 cream was evaluated as a non-irritating material. In the eye irritation test, 0.3% DA-5018 cream and Zostrix-HP cream could be considered as mildly irritating materials. But, the base of 0.3% DA-5018 cream was a non-irritating material. These results suggest that 0.3% DA-5018 cream has mildly irritating activity and its irritancy is similar to that of Zostrix-HP cream.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.354-363
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• 1996

This study was conducted to investigate the repeated dose toxicity of DA-9601, an antiulcer agent of Artemisia app. extract, in rats. DA-9601 was administered orally once a day for 4 weeks to 10 males and 10 females per group at doses of 0(vehicle control), 125, 500 or 2000 mg/kg/day. Throughout the study, no treatment-related deaths and clinical signs were observed. In female rats receiving 125 mg/kg of DA-9601, water consumption increased slightly on day 4, 11 and 25. Hematological examination showed a decrease of MCV and an increase of PLT in male rats at the doses of 500 and 2000 mg/kg groups. Blood biochemistry revealed slight decreases of cholesterol, BUN and Na in male rats and decreases of total bilirubin and creatinine and slight increases of globulin and Cl in female rats. The organ weights at the end of 4 weeks showed slight changes in some organs of treated groups. But, all these changes were not considered to be of toxicological importance, because they did not show dose-response relationship and relevance to gross and microscopic findings. Histopathologically, abnormal treatment-related changes were not observed in any organ and target organs were not detected. On the basis of these results, the NOAEL(no-observed-adverse-effect level) of DA-9601 was estimated to be more than 2000 mg/kg/day under the conditions tested.

• Journal of Soil and Groundwater Environment
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• v.15 no.3
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• pp.1-6
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• 2010

This study investigated the change of metal contamination levels according to amendment of enforcement regulation of the Soil Environmental Conservation Act in Korea. As an analytical result of 87 samples in abandoned metallic mine area, the extracted amount of As, Pb and Cu with aqua regia was 4.3~29.6 times higher than that with hydrochloric acid extraction and the number of samples, which contamination levels were found to exceed soil contamination standards, was also increased. On the other hand, in case of Cd, Zn, and Ni, the number of samples, which contamination levels were found to exceed soil contamination standards, was decreased or similar. These results can be used as a preliminary material in comparison between the soil pollution data accumulated previously and the data obtained by the revised standard method for the examination of soil pollution.

• Journal of Soil and Groundwater Environment
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• v.20 no.1
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• pp.28-35
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• 2015

In this study, the mechanisms on ultrasonication enhanced metals extraction were investigated compared with the conventional washing technique. We hypothesized the mechanisms on enhanced extraction of ultrasonication: ultrasonication increased the temperature of soil slurry and decreased average particle size of soil due to breakdown of soil aggregate. Actually, the ultrasonication increased the temperature of soil slurry to $60^{\circ}C$ in this study, and the increase in the temperature enhanced the metal extraction to 15-20% even in the conventional simple mixing. The conventional washing technique decreased average size of soil particles because of breakdown of soil aggregate, and the ultrasonication decreased the size more than that of washing. The breakdown of soil aggregate improved the contact between metals and washing agent, which enhanced the extraction of metals in the ultrasonication. Therefore, we concluded that the main mechanisms of ultrasonication are increase in the temperature and breakdown of the soil aggregate. Finally, the ultrasonicaiton increased the extractability of metals upto 40% compared to conventional washing technique.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.38-40
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• 1987

To optimize the preparation condition of oil in water microemulsion rheological method was used. The viscosity-temperature curve of refined soybean oil was recorded and from this result microemulsion was prepared at various temperatures and evaluated by Coulter counter during 3 weeks. The difference in rheograms of crude emulsion and the microemulsion varying the number of passes in the homogenizer was also examined. From above experiments following conclusions were obtained. 1) Through all the process, temperature was an important factor and the optimum was $60-80^{\circ}C$. 2) By first pass in the homogenizer, most oil droplets were finely dispersed. 3) In the homogenizing step the higher pressure results in the finer dispersion but as the pressure goes up, the differential efficiency of dispersion was decreased.

• Biomolecules & Therapeutics
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• v.4 no.3
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• pp.224-231
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• 1996

DA-5018, a non-narcotic analgesic agent, was examined for mutagenicity in the reverse mutation test on bacteria, chromosomal aberration test on cultured mammalian cells and micronucleus test on mice. The reverse mutation test was performed by a plate incorporation method with or without a metabolic activation system(S9 mix) using Salmonella typhimurium strain TA100, TA1535, TA98 and TA1537. DA-5018 did not significantly increase revertant colonies in any of the test strains under any conditions at concentrations ranging from 0.0049 to 1.25 mg/plate, compared with the vehicle control. In the chromosomal aberration test using cultured Chinese Hamster Lung(CHL) cells, DA-5018 did not increase the number of aberrant cells in the presence or absence of S9 mix at concentrations of 0.016 mM/plate to 0.25 mM/plate, compared with the vehicle control. In the micronucleus test, male ICR mice were given DA-5018 intraperitoneally at a dose level of 0.55, 1.10 and 2.20 mg/kg. The incidence of bone marrow micronucleated polychromatic erythrocytes in the DA-5018 treated mice was not significantly different from that of the vehicle control. These results indicate that DA-5018 does not have mutagenic potential under the present test conditions.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.155-160
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• 1990

An oral adhesive tablet of acyclorir [9-(2-hydroxyethoxymethyl) guanine] for herpetic stomatitis was prepared and its physical properties were evaluated. 300 mg weighed tablets containing 30 mg of acyclovir were prepared with six kinds of polymers from direct compression, and the stickiness, fracture resistance and dissolution in pH 6.8 buffer solution were tested. HPMC and MC showed good stickiness and fracture resistance, and their dissolution rates were significantly different from each other. Three factors-HPMC:MC ratio, acyclovir content, compression force-were chosen as an important factor of manufacture and factorial analyses for these three factors were carried out. Eight kinds of formulations from different combination of three factors were prepared and tested in stickiness, fracture resistance and dissolution in pH 6.8 buffer solution. Dissolution rate was significantly affected by polymer ratio, fracture resistance was affected by compression force, and stickiness was not significantly affected by acyclovir content and polymer ratio.

• YAKHAK HOEJI
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• v.40 no.1
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• pp.10-18
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• 1996

Daunirubicin and doxorubicin analogues (5,7,8,9,) in which the natural amino sugar, daunosamine, is replaced by rhamnopyranosyl or 4'-amino rhamnopyranosyl residues have been p repared. The in vitro cytotoxicity of compound 5 or 7 was similar to that of doxorubicin for P388 murine leukemic cell line. But compound 8 or 9 was less cytotoxic than doxorubicin. When administered intravenously on day 1, compound 9 showed antitumor activity comparable to that of doxorubicin against ip-inoculated L1210 murine leukemia and found to be less toxic than doxorubicin. But the in vivo antitumor activity of compound 7 or 8 was inferior to that of doxorubicin.