• Biomolecules & Therapeutics
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• v.19 no.4
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• pp.425-430
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• 2011

In this study, we found that Forsythiae fructus (FF) and one of its main compounds, arctigenin, significantly inhibited nitric oxide production in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Arctigenin also suppressed the expression of inducible nitric oxide synthase and cyclooxygenase-2, and inhibited the activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38. Moreover, it also reduced levels of proinflammatory cytokines, interleukin $1{\beta}$, tumor necrosis factor ${\alpha}$ and prostaglandin E2, and inhibited neuronal death in LPS-treated organotypic hippocampal cultures. Therefore, we suggest that arctigenin may confer a neuroprotective effect via the inhibition of neuroinflammation.

• Korean Journal of Pharmacognosy
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• v.23 no.2
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• pp.77-80
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• 1992

The essential oils of Elscholtzia ciliata and the cultivated tissue have been studied. The composition and contents of essential oils were identified by gas chromatography and mass spectrometry. The main component of essential oils of E. ciliata was naginata ketone. The essential oils from the flowers, leaves and stems of E. ciliata showed similar patterns of gas chromatogram. In experimental studies on the tissue culture of callus, it has been found that NAA induced higher growth rate and higher content of essential oils than 2, 4-D. The essential oils from the cultivated callus showed different composition from that of mother plants.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.297-300
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• 2005

This paper presents vibration control of an engine mount for a passenger vehicle utilizing ER fluid and piezoelectric actuator. The proposed engine mount can be isolated the vibration of wide frequency range with many types of amplitude. The main function of ER fluid is to attenuate vibration for low frequency with large amplitude, while the piezoelectric actuator is activated in hish frequency range with small amplitude. A mathematical model of the engine mount is derived using Hydraulic model and mechanical model. After formulating the governing equation of motion, then field-dependent dynamic stiffness of the engine mount is evaluated for various engine speed and excitation amplitude conditions. Then robust controller is designed to attenuate vibration of wide range frequency component. Computer simulation is undertaken in order to evaluate the vibration control performance such as transmissibility magnitude in frequency domains.

• Journal of the Korean Applied Science and Technology
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• v.15 no.1
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• pp.17-23
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• 1998

To prepare a O/W type nonionic durable softner(ANSA), synthesized 1, 3-dihexadanoyl-2, 7-dioxy-6, 8-di(2-hexadecanoyloxyethyl)-1, 3, 6, 8-tetraazacyclodecane as the main component of softner, was blended with beef tallow, anhydrous lanolin, polyoxyethylene(20) oleyl ether, sorbitan sesquioleate, and polyoxyethylene(7) stearyl ether in various compositions. Emulsion stability of ANSA was good, and the mixed HLB value was 9.8. After the treatment of ANSA to all cotton fabrics, the physical properties such as tear strength, crease recovery, and flexing abrasion resistance were measured, respectively. As a result of the measurement, ANSA was proved to be durable softner with good softness.

• Bulletin of the Korean Chemical Society
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• v.20 no.11
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• pp.1313-1318
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• 1999

Lewis bases were employed to control the stoichiometry of ferrite film prepared by light enhanced plating (LEP) technique. When 2,2'-bipyridyl was used as a Lewis base, conversion electron Mosbauer spectroscopy (CEMS) and x-ray powder diffraction (XRD) experiments showed that the main component of the ferrite films was metal-deficient magnetite (Fe3(1-δ)O4). Nonstoichiometry and roughness of LEP films were increased by the addition of 2,2'-bipyridyl. Using ethylenediaminetetraacetate (EDTA) as a Lewis base, produced film that was a mixture of magnetite and Υ-FeO(OH). No low temperature transition (Verwey transition) of magnetite was detected in resistivity and ac-susceptibility measurements for the LEP films. Surface morphology of the LEP films was observed by atomic force microscopy (AFM). The size of dominant particles was about 0.2 μm.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.239-260
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• 2000

The raw materials requiring new technology have been introduced to the market as highly functional cosmetics have been popularized recently. The doublesphere which is the new capsulation is thus born. The deublesphere is double-layered capsulation of which the primary film is the nanocapsulation of liposome and the secondary film is the visible capsulation. The main component of the primary film is lecithin and that of the secondary film is alginlcarrageenanslagarfcellulose. The doublesphere is characterized by that it is possible to keep active beautifying components stable and to improve the moisturizing effect, penetration power into the skin, roughness of the skin, etc. in view of its efficacy and effects since it is double-layered capsulation. The doublesphere-retinol is made in order to measure the stability, efficacy, and effects in the present study.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.454-459
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• 2006

There are two main streams for pattern classification technology One is the method using PCA (Principal Component Analysis) and the other is the method using Neural network. Both of them have merits and demerits. In general, using PCA is so simple while using neural network can improve algorithm continually. Algorithm using neural network needs so many calculations rendering very slow response. In this work, an attempt is made to develop algorithms adopting both PCA and neural network merits for simpler, but faster and smarter.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.687-689
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• 1995

Our team works on mixture of hard magnetic materials. As hard magnetic material we used mixture of powders: melt-spun ribbon Nd-Fe-B, ferrite and Alnico. Their different mixtures are basic material for dielectromagnets under our investigation. Main disadvantage of dielectromagnets with Nd-Fe-B alloy powder as a component is a low corrosion resistance. Protection against corrosion is covering dielectromagnets with metallic or organic coating film. The coating film protects dielectromagnets from free particles on the surface and low resistance for mechanical stresses too. The surface of dielectromagnets prepared from mixture of powders if formed by metallic particles - powder of Nd-Fe-B and Alnico, particles of oxide - powder of ferrite and particles of resin - bonding materials. Team work on technology of laying the metallic coating on dielectromagnets prepared from mixture of mentioned powders. Papers show the results of initial investigation on metallic coating technology. It shows influence of type and used technology of the metallic coating film on magnetic properties of dielectromagnets.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.88-92
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• 1969

As a part of series of "Studies on Inorganic Chinese Drugs in Korea" four arsenic mineral Chinese drugs were analyzed by emission spectrographic method, and also were studied crystallographically by X-ray diffraction method. The following results were revealed: 1) Tang-shin-suk was not a Native arsenic but a Arsenolite which containing 94% of $As_{2}O_{3}$, 2) Toh-shin-suk was Crade Aluminum silicate 3) Woong-whang was a Realgar $As_{2}S_{2}$, 4) Yeh-suk was a Ca-Al-Silicate which was mixed with .alpha.-quartz contaminated by Iron compound and trace amount of Arsenic. It was not verified that the presence of Arsenopyrite FeAsS which has been believed as a main component of Yeh-suk by a Japanese author Wakimizu, nor the presence of Arsenolite which was reported by Masutomi.

• Journal of the Optical Society of Korea
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• v.17 no.6
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• pp.471-480
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• 2013

The beating of two or more lasers that have the same or a finite difference in the central frequencies, is the main source of noise in spectral amplitude coding optical code division multiple access (SAC OCDMA) systems. In this paper we adopt a spatial multiplexing (SM) scheme for SAC OCDMA systems to mitigate this beat noise. The results show that for different code weights and different data rates SM SAC can support a larger number of users than the conventional SAC for all different laser source configurations. However, SM SAC requires a more complex system than the conventional SAC, and almost twice as much optical component.