• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.6
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• pp.610-619
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• 2000

This paper presents an off-line UPS using the high temperature superconductive magnetic bearing. FES(Flywheel Energy Storage) system has good advantages in compare with lead acid battery. So, high efficiency FES using high temperature SMB(superconductive magnetic bearing) was composed in this paper. The outer rotor type of PMSM(Permanent Magnet Synchronous Motor) as motor/generator was used for the experiment, and square wave current and sinusoidal wave control methods was compared for high efficiency operation of motor/generator. The circuit for in phase sinusoidal wave current control with EMF in the full speed range was designed and the proposed flywheel energy storage system was applied in single phase off-line UPS system. As the stable operation characteristics of prototype system was confirmed, the its excellence as energy storage device in Off-line UPS was proved.

• Journal of Society of Preventive Korean Medicine
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• v.7 no.2
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• pp.97-106
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• 2003

This study was performed to determine the cytotoxic effect of methanol extract from medicinal plants. 1. The cell viability was determined by MTT method. Their cytotoxic activities against three cancer cell lines such as A549, MDA-MB-231 and SNU-C4 cell line were tested. 2. Among them, The methanol extract of Saururus Ohinensis Bail showed the strongest cytotoxic effect against SNU-C4 cells. These results suggest that the methanol extract of Saururus Ohinensis Bail possessed a potential antitumorous agent. 3. The free radical scavenging activity using DPPH method was the strongest of Saururus Chinensis Bail extract.

• Journal of Korean Society for Quality Management
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• v.36 no.1
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• pp.20-30
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• 2008

Nowadays many countries in the world have been implementing TQM which is originated from Japanese management style. There are many research results that TQM has a positive influences on business results. But the levels of implementing TQM are different by countries. The domestic competitors and the customers, who have the great influences on business results are also quite different. Therefore the levels of TQM in some company and the influences of TQM factors on business results are supposed to be different by countries. The situations of the countries lying on the more developed stage will be a good benchmarks for the countries on following stages. There are few researches on this cross countries analysis. This paper do the empirical study on the effects of TQM factors on business results between Korean and Japanese small or medium sized manufacturing companies. First, the levels of TQM are compared between countries. Second, what key success factors among TQM ones are for business success is analyzed for each country and compared between two countries. This study will help to plan the road maps in TQM journey for the Korean companies.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.675-679
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• 2006

The effect of water extract from Thesium chinese Turczaninow (TCTW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. TCTW inhibited the growth of both estrogen-independent MDA-MB-231 and estrogen-dependent MCF-7 human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by TCTW at the concentrations of 1.0 (p<0.05) and 5.0 mg/ml (p<0.005). Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of TCTW in Western blot analysis. TCTW inhibited induction of ornithine decarboxylase by 12-O-tetradecanoylphorbol-13-acetate (TPA), a key enzyme of polyamine biosynthesis, which is enhanced in tumor promotion. Therefore, TCTW is worth further investigation with respect to breast cancer chernoprevention or therapy.

• Biomolecules & Therapeutics
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• v.24 no.1
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• pp.62-66
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• 2016

Amygdalin, D-mandelonitrile-${\beta}$-D-glucoside-6-${\beta}$-glucoside, belongs to aromatic cyanogenic glycoside group derived from rosaceous plant seed. Mounting evidence has supported the anti-cancer effects of amygdalin. However, whether amygdalin indeed acts as an anti-tumor agent against breast cancer cells is not clear. The present study aimed to investigate the effect of amygdalin on the proliferation of human breast cancer cells. Here, we show that amygdalin exerted cytotoxic activities on estrogen receptors (ER)-positive MCF7 cells, and MDA-MB-231 and Hs578T triple-negative breast cancer (TNBC) cells. Amygdalin induced apoptosis of Hs578T TNBC cells. Amygdalin downregulated B-cell lymphoma 2 (Bcl-2), upregulated Bcl-2-associated X protein (Bax), activated of caspase-3 and cleaved poly ADP-ribose polymerase (PARP). Amygdalin activated a pro-apoptotic signaling molecule p38 mitogen-activated protein kinases (p38 MAPK) in Hs578T cells. Treatment of amygdalin significantly inhibited the adhesion of Hs578T cells, in which integrin ${\alpha}5$ may be involved. Taken together, this study demonstrates that amygdalin induces apoptosis and inhibits adhesion of breast cancer cells. The results suggest a potential application of amygdalin as a chemopreventive agent to prevent or alleviate progression of breast cancer, especially TNBC.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.359-363
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• 2004

I investigated an effective way to generate a metagenomic library from DNA prepared from environental samples. The sizes of DNA extracted from environmental samples were usually in the range of 10 to 100 kbp as estimated from $0.4\%$ agarose gel electrophoresis. Because of this small size, a fosmid, rather than BAC, was chosen as a vector. It was found that, for the successful generation of metagenomic library, the selection of DNA with the sized of about 40 kbp was critical and, therefore, a simple agarose gel electrophoresis system was developed to select this size of DNA. By the procedure described in this report, I obtained metagenomic libraries containing 25,000 fosmid clones, which corresponded to 1,000 Mb of metagenomic DNA.

• Journal of Internet Computing and Services
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• v.4 no.1
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• pp.75-86
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• 2003

In this paper, we extended hierarchial structure of managed object class to support Role-Based Access Control, and described constraint conditions that have support dynamic temporal function as well as statical temporal function established by management process. And we defined about violation notifications should report to manager when rules violate constraint conditions. Also we presented system architecture that support RBAC with MIB(Management Information Base) of ITU-T recommendation. By access control enforcement and decision function, constraint conditions and activated translation procedure of each roles are described, our system presents dynamic temporal property systematically.

• Journal of the Korean Ceramic Society
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• v.45 no.11
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• pp.688-693
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• 2008

This paper presents a study on the photocatalytic reaction about the composite particles of $TiO_2$-coated phosphors under visible light irradiation. Nanocrystalline titanium dioxide layers were directly coated on the alkaline earth aluminate phosphor, $CaAl_2O_4:Eu^{2+},\;Nd^{3+}$ particles by an sol-gel processing method. The photocatalytic reaction was analyzed with the degradation of methylene blue (MB) aqueous solution under UV and visible light irradiations. $TiO_2$-coated phosphor powders showed different photocatalytic mechanism, compared with pure $TiO_2$ (P-25, Degussa). Under UV-irradiation, $TiO_2$-coated phosphor powders showed slow photocatalytic reactivity in the early stage and fast in the latter, compared with that of pure $TiO_2$. However, $TiO_2$-coated phosphor powders showed much faster photocatalytic reactivity than that of pure $TiO_2$ under visible irradiation. In addition, the characterizations of the $TiO_2$-coated phosphor powders were conducted by a X-ray diffractometer (XRD), transmission electron microscope (TEM), and energy dispersive spectroscopy (EDS).

• The Journal of Korean Association of Computer Education
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• v.3 no.1
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• pp.109-115
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• 2000

In this paper, we have designed the management System to monitor and control computers running on MS Windows in the PC room using SNMP. The proposed system has controlling capability to control the status of PC and monitoring functions to have real-time monitoring and process control. In the controlling system, it supports update and setting of the configuration information of PC and backup/restore the information when it happens to be some faults. In the monitoring system, it has monitoring the PC of students, controlling the process on PC, and invoking a new job. This system contributes to enhance the effectiveness of teacher's educational activities in PC room by controlling and monitoring the program running on student's computer.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.1-8
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• 2011

5-axis NC machining has a good advantage of the accessibility of tool motion by adding two rotary axes. It offers numerous advantages such as expanding machining fields in parts of turbo machineries like impeller, propeller, turbine blade and rotor, reasonable tool employment and great reduction of the set-up process. However, as adding two rotary axes, it is difficult to choose suitable machining conditions in terms of cutter path and cutter posture at a cutter contact point. Therefore in this paper, it is proposed to decide suitable machining condition through an experimental method such as adopting various cutter paths, cutter postures types. Also, in order to increase the efficiency of 5-axis machining, it is necessary to minimize the cutter posture changes and create a continuous cutter path while avoiding interference. This study, by using an MC-space algorithm for interference avoidance and an MB-spline algorithm for continuous control, is intended to create a 5-axis machining cutter path with excellent surface quality and economic feasibility. finally, this study will verify the effectiveness of the suggested method through verification processing.