• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.11
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• pp.95-105
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• 2005

The HAUSAT-2 nanosatellite which is scheduled to launch in 2008 is being developed by SSRL(Space System Research Lab.). The HAUSAT-2 STM(Structural-Thermal Model) was developed as the first system model to verify structural and thermal design margin. The qualification level vibration and thermal tests have been conducted on STM. This paper addresses the comparison of structural analysis and test results of HAUSAT-2 STM. It was shown that the natural frequency of HAUSAT-2 STM satisfies the stiffness requirements without structural damage in the random vibration test. The assembly and integration validity were also checked out through STM.

• Journal of Energy Engineering
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• v.6 no.2
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• pp.145-151
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• 1997

The R&D investment of power industry has significant influences on the social welfare as well as national economy. It is necessary to analyze how efficient the R&D investment has been performed. The objective of this study is to verify the efficiency of the R&D investment in the domestic power industry. A formula was introduced to by calculate the appropriate amount of R&D investment of monopolistic industry under the regulations which are determined by the proportion of R&D elasticity and price elasticity. It has resulted that there would be no economy of scale as the sales of electricity increases at the same rate of the increasing cost. The R&D investment in the present electricity industry has been performed inefficiently by showing the negative impact on price-cost margin of the intensity of R&D investment, which is the extent of R&D investment to reinforce economy of scale.

• Herbal Formula Science
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• v.15 no.2
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• pp.119-126
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• 2007

Objectives: This study presents observation of microorganism such as total aerobic bacteria, total fungus, E. coli, Pseudonomas aerugjnosa, Staphylococcus aureus, and Salmonella typhimurium in herbal decoction manufactured by Korean medical clinic. Methods: We examined to observe microorganism using the requirements for the experimental methods recommended by FDA. For the identification, we observed microscopic methods and carried out polymerase chain reaction (PCR) and DNA purification. The purified DNA samples were analyzed by DNA sequencer. As compared with NCBI database. the results were identified by sequences similarity. Results and conclusion: 26 (55%) of 46 decoctions observed positive for microbial test. 12 (46 %) of 26 positive decoctions exceed requirement of microbial limit test. These microbial colony identified genus of Bacillus using microscopic and DNA sequencing methods.

• Herbal Formula Science
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• v.15 no.2
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• pp.113-117
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• 2007

Objectives: Samul-tang(Siwu-tang) has been traditionally prescribed a medicine as a restorative. Methods: In this study, we investigated the acute toxicity about water-extracted Samul-tang(Siwu-tang). Twenty-five mice completed 14 days of oral Samul-tang(Siwu-tang) at the respective doses of 0(control group), 2560, 3200, 4000 and 5000mg/kg. Results: We observed survival rates, general toxicity, change of body weight, and autopsy. Conclusions: Compared with the control group, we could not find any toxic alteration in all treated groups (2560, 3200, 4000 and 5000mg/kg). $LD_{50}$ of Samul-tang(Siwu-tang) was over 5000mg/kg and it is very safe to ICR mice.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.485-490
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• 2010

We propose the equivalent circuit model including all parasitic components in input gate of sense amplifier of DDI DRAM with butting contact structure. We analysed the effect of parasitic schottky diode by using the proposed model in the operation of sense amplifier. The cause of single side fail and the temperature dependence of fail rate in DDI DRAM are due to creation of the parasitic schottky diode in input gate of sense amplifier. The parasitic schottky diode cause the voltage drop in input gate, and result in decreasing noise margin of sense amplifier. therefore single side fail rate increase.

• The Journal of Korean Medicine
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• v.37 no.3
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• pp.39-46
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• 2016

Objectives: The present study aimed at investigating the effects of Schisandrae Fructus (SF) on menopause symptoms in ovariectomized mice. Methods: 6 weeks old female mice were ovariectomized (OVX), and the OVX mice were fed with a three doses of SF (25, 100, and 400 mg/kg, respectively) or $17{\beta}$-estradiol (E2, 0.5 mg/kg) 3 times a week for 6 weeks. Body weight was measured at every week and uterus weight was also measured at the end of experiment. Lipids and osteocalcin levels in serum were analyzed. Results: The uterine weight was not changed in SF treated group, while E2 intake increased the reduced uterine weight by OVX. Although Body weight was increased since two weeks after ovariectomy compared with sham operated group, there was no change in SF or E2 treated group compared with OVX. But LDL was significantly reduced in SF (400 mg/kg) or E2 fed mice and SF or E2 treatment decreased enhanced osteocalcin level by OVX. Conclusion: These results indicated that SF would be effective in the improvement of LDL level and osteoporosis on menopause.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.19-23
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• 2015

In this paper, we present the return link ACM method to improve the link availability and system throughput for satellite communication service. Also, we describe the optimization of an algorithm for channel prediction using the LMS (Least Mean Square) adaptive filter and the MODCOD (Modulation & Code rate) decision. The simulation results show that the optimized filter taps and step-size of adaptive filter are 2 and 0.00026, respectively. And also confirms the required SNR margin for minimization of MODCOD decision error is 0.3dB.

• Journal of the Korea Computer Industry Society
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• v.2 no.3
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• pp.321-328
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• 2001

Existing internet auction systems have adopted the form which gives a win to the auction bidder who proposes the top bid price for the goods posted on the auction board. But they haven't been satisfying the automatical one-step processing for user’s convenience because they must require continuous care of user for bidding and checking as well as neglecting the convenience of user interface while participating in the electronic bidding system. The agent push mail to a auctioneer information that able to get how much profit as calculate duration time and start price with bidding history stored database. So, this thesis propose a multi-agent system in internet auction that generate the highest margin for auctioneer’s goods.

• Korean Journal of Oriental Medicine
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• v.6 no.1
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• pp.107-116
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• 2000

Vibrio become prevailing if superficial temperature of ocean is raised and their activities of area are expanded and most of ocean creatures(fishes, oysters etc) are polluted with vibrio. The one who has taken these polluted fishes and oysters uncooked caused foodpoisoning and diarrhea from Vibrio. Frequently these diseases breakout is disposed in westsea shore of Korea. According to ancient and traditional Korean medical book - Kumkue Yorak - and their single, we carried out experiment check the activities of natural medicinal effects on Vibrio parahemolyticus. The prescriptions of trial materials are processed from extraction boiling water and 80% methanol and followed by freeze dried and adsorbed to every discs in dosage of 10mg. Gentamycin of 10mg were used for control. The result of compound prescription displayed special diseases in antimicrobial activities of boiling water and MeOH extraction compared with control. In single prescription, extraction of boiling water and MeOH of Schisandra sphenanthera(clear zone : 15mm) presented extraordinal antimicrobial activity. The MBC of Schisandra sphenanthera extracts was expressed 2.56mg/ml in boiling water and MeOH.

• Korean Journal of Oriental Medicine
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• v.6 no.1
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• pp.117-122
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• 2000

The purpose of this study is to compare the contents of heavy metals of boiled ssangwhatang with those of herbal ingredients which are composed of ssangwhatang. Ssangwhatang is used for antifatigue, tonic and so on. With industrial development, our environment has been very polluted. Herbal medicines also are seriously contaminated by heavy metals and pesticides. The herbal medicines of ssangwhatang were bought at 10 defferent markets. The contents of 14 heavy metals(Ag, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Sn, Zn) were analysed using ICP. It was found out that 7 heavy metals(Pb, As, Ba, Cd, Hg, Sb, Sn) were not detected at all in boiled ssangwhatangs. But they were detectable in all ssangwhatangingredients before boiling. For example, the content of Pb in one pack of ssangwhatang before boiling was $0.039^{\circ}{\pm}0.005mg$ and Pb in boiled one was not detected. Herbal medicine itself is seriously contaminated by heavy metals. These results suggest that boiled ssangwhatang which we take is safe from the contamination of heavy metals.