• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.12-20
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• 1998

Primary neuronal culture was studied for observing effect of ginsenoside Rgl (Rgl) on serum-free medium induced apoptosis. Results showed that Rgl at concentration of 1 umol$.$ L-1 and 10 umol$.$L-1 could inhibit apoptosis, decrease intracellular calcium concentration in cultured cortical neurons, enhance SOD activity in both aged rat cortex and cultured cortical neurons, scavenge cytotoxic oxygen free radicals, decrease NO content and NOS activity in aged rat cortex and cultured cortical neurons, increase bel-2 gene expression in rat brain. These results provided new data for elucidating the anti-aging effect of Rgi. Rgl is considered to be a useful drug for treatment of Alzheimer's disease and brain aging.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.59-63
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• 2006

Secalonic acid D(SAD) was isolated as the major secondary metabolite of the marine lichen-derived fungus Gliocladium sp. T31. Its structure was established on the basic of physicochemical and spectroscopic data. This is the first report on the isolation of SAD from this fungus, as well as its inhibitory effect on K562 cell cycle and its cytotoxicity against several tumor cell lines in vitro.

• Journal of the Korean Electrochemical Society
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• v.5 no.4
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• pp.212-215
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• 2002

A superoxide dismutase (SOD)-based superoxide ion $(O_2^-)$ sensor was fabricated by immobilizing SOD on a self-assembled monolayer (SAM) of 3-mercaptopropionic acid (MPA) which was prepared on a gold electrode. The SAM of MPA was found to function as an effective promoter for the electrode reaction of SOD. The amperometric response to $(O_2^-)$ was monitored at 300mV and -100mV vs. Ag/ Agel in 5mM phosphate buffer solution containing $KO_2$. The sensor was proved to have a high sensitivity, selectivity and short response time (<5 s) and negligible interference.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1379-1382
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• 2009

The 3D display has been used in optical projection technology to connect twenty mini- projectors with seamless image tiling. In this way, we can improve the projected resolution by reducing each project screen and increase projected area by connect several mini-projectors. In this article, the illumination system uses the LED light source, non- telecentric structure and LCOS panel, and it's total length is less than 10 centimeter. It can build a seamless large display by tiling multiple projectors.

• Journal of Communications and Networks
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• v.11 no.4
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• pp.350-358
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• 2009

In a wireless sensor network (WSN) setting, this paper presents a distributed decision-making framework and illustrates its application in an online structural health monitoring (SHM) system. The objective is to recover a damage severity vector, which identifies, localizes, and quantifies damages in a structure, via distributive and collaborative decision-making among wireless sensors. Observing the fact that damages are generally scarce in a structure, this paper develops a nonlinear 0-norm minimization formulation to recover the sparse damage severity vector, then relaxes it to a linear and distributively tractable one. An optimal algorithm based on the alternating direction method of multipliers (ADMM) and a heuristic distributed linear programming (DLP) algorithm are proposed to estimate the damage severity vector distributively. By limiting sensors to exchange information among neighboring sensors, the distributed decision-making algorithms reduce communication costs, thus alleviate the channel interference and prolong the network lifetime. Simulation results in monitoring a steel frame structure prove the effectiveness of the proposed algorithms.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.213-214
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• 2015

The first successful case of a CM application in Shanghai, China in 1993 presented its possibility. According to the State Council's 'Investment system reformation', in 2004, more than 40 sub-provincial divisions in China were increased the productivity of construction by the CM application. It is predicted that CM will be utilized as a technical management method at government's plan, which raises the urbanization level more than 60% through the construction industry by 2020. However, compared with increasing CM demands, there are no complete evaluation criteria of CM in china. For instance, 26 areas in china arrange criteria individually, so. Therefore, it is necessary to establish integrated evaluation criteria on the basis of regional ones. This research will draw the evaluation criteria of selecting for the China CM Corporation in order to vitalize CM system.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.57-71
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• 2007

This paper considers how to detect structure change in persistence from I(1) to I(0) with innovations in the domain of attraction of a K-stable law. We derive the asymptotic distribution of test statistic and find that the asymptotic distribution of test statistics depends on the stable index K, which is often typically unknown and difficult to estimate. Therefore the subsampling method is proposed to detect changes without estimating K. We establish the asymptotic validity of this method and assess its performance in finite samples by means of simulation study.

• Structural Engineering and Mechanics
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• v.6 no.4
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• pp.457-466
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• 1998

The dynamic response of an elastic torsion shaft of revolution is analysed by the Line-Loaded Integral Equation Method (LLIEM). A "Dynamic Point Ring Couple" (DPRC) is used as a fictitious fundamental load and is distributed in an elastic space along the axis of the shaft outside the shaft occupation. According to the boundary condition, our problem is reduced to a 1-D Fredholm integral equation of the first kind, which is simpler for solving than that of a 2-D singular integral equation of the same kind obtanied by Boundary Element Method (BEM), for steady periodically varied loading. Numerical example of a shaft with quadratic generator under sinusoidal type of torque is given. Formulas for stresses and dangerous frequency are mentioned.

• Structural Engineering and Mechanics
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• v.6 no.4
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• pp.377-394
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• 1998

Slit shear walls an reinforced concrete shear wall structures with purposely built-in vertical slits. If the slits are inserted with visco-elastic damping materials, the shear walls will become viscoelastic sandwich beams. When adequately designed, this kind of structures can be quite effective in resisting earthquake loads. Herein, a simple analysis method is developed for the evaluation of the stochastic responses of visco-elastic slit shear walls. In the proposed method, the stiffness and mass matrices are derived by using Rayleigh-Ritz method, and the responses of the structures are calculated by means of complex modal analysis. Apart from slit shear walls, this analysis method is also applicable to coupled shear walls and cantilevered sandwich beams. Numerical examples are presented and the results clearly show that the seismic responses of shear wall structures can be substantially reduced by incorporating vertical slits into the walls and inserting visco-elastic damping materials into the slits.

• Structural Engineering and Mechanics
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• v.22 no.2
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• pp.241-262
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• 2006

NiTi-wire shape memory alloy (SMA) dampers, that utilize NiTi SMA wires to simultaneously damp tension, compression and torsion, was developed for structural control implementation in this study. First, eight reduced-scale NiTi-wire SMA dampers were constructed. Then tension, compression and torsion experiments using the eight reduced-scale NiTi-wire SMA dampers of different specification were done. The experimental results revealed all of the eight reduced-scale NiTi-wire SMA dampers had the ability to simultaneously supply tension-compression damping and torsion damping. Finally, mechanics analysis of the NiTi-wire SMA dampers was done based on a model of the SMA-wire restoring force and on tension-compression and torsion damping analysis. The damping analytical results were found to be similar to the damping experimental results.