• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.83-91
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• 1997

Phenolic acids are regarded as harmful materials in food and environment science. But recently, regarded as useful materials by their characteristics which bind metal ions and have pharmaceutical effect. It was necessary to remove or recover phenolic acids from solutIon containing phenolic acids. Continuous fixed-bed adsorption was adapted in order to separate phenolic acids from diluted solution and the breakthrough curve was predicted by nonlinear curve fitting method. The larger bed length showed the longer breakpoint time and the slow mass transfer coefficient. Ferulic acid among the phenolic acids was passed through the breakpoint first and the second and. third were p-coumaric acid and gallic acid. These orders were caused by not only ionic strength between adsrobent and adsorbate but also molecular weights.

• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.122-129
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• 2000

Field emission behavior from vitreous carbon powders deposited on Mo coated glass by electro-phoretic method was investigated. Although the vitreous carbon has only $sp^2$ hybridized carbon bond, we could observe an excellent field emission behavior. Reproducible electron emission was observed without initiation process which is known to be needed in most carbon cathode materials. Critical electric field for electron emission was in the range from 3 to 4 MV/m. The effective work function was estimated to be about 0.06 eV, as obtained from the slope of Fowler-Nordheim plot. The stability of the emission behavior characterized by repeated I-V measurements, was much superior to the Si tips. We observed the possibility of full area light emission in vitreous carbon materials. This results showed that the field emission is not intimately related to the $sp^3$ hybridization of carbon, but the electrical properties of cathod/electrode interface or the conductivity of the cathode materials which required for the electron transport to the cathode surface.

• Journal of Korea Water Resources Association
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• v.42 no.10
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• pp.809-824
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• 2009

Hydrological system forecasting, which is the short term runoff historical data during the limited period in dam site, is a conditional precedent of hydrological persistence by stochastic analysis. We have forecasted the monthly hydrological system from Andong dam basin data that is the rainfall, evaporation, and runoff, using the seasonal ARIMA (autoregressive integrated moving average) model. Also we have conducted long term runoff simulations through the forecasted results of TANK model and ARIMA+TANK model. The results of analysis have been concurred to the observation data, and it has been considered for application to possibility on the stochastic model for dam inflow forecasting. Thus, the method presented in this study suggests a help to water resource mid- and long-term strategy establishment to application for runoff simulations through the forecasting variables of hydrological time series on the relatively short holding runoff data in an object basins.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.244-248
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• 1994

Magnetic and Magneto-optical characteristics of NdTbFeCo alloy films and NdTbFeCo/TbFeCo double-layered films have been investigated. It was observed that the Kerr rotation(${\theta}_{k}$) in the short wavelength region increased and the coercivity decreased as the substitutional amount of Nd for Tb in NdTbFeCo film at the constant FeCo content. In spite of the increased ${\theta}_{k}$, a small coercivity of NdTbFeCo film made this medium unsuitable for magneto-optical recording medium at short wavelength. An effort was made to improve coercivity by exchange coupling with TbFeCo film of high coercivity. In the exchange-coupled $Nd_{16.9}Tb_{15.2}Fe_{50.4}Co_{17.5}(150\;{\AA})/Tb_{21.1}Fe_{65.0}Co_{13.9}(300\;{\AA})$ double-layered film, the magnetization reversal switching field and the Kerr rotation angle were increased to about 6.0 KOe and $0.32^{\circ}$ at 500 nm, respectively. This result indicates that exchange-coupled NdTbFeCo/TbFeCo film can be a promising candidate for agneta-optical rerding medium short wavelenhth.

• Biomedical Science Letters
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• v.5 no.1
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• pp.11-15
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• 1999

Thyroxine (3,5,3',5'-L-tetraiodothyronine; T$_4$) is the most commonly measured thyroid hermono for the diagnosis of various thyroid disorders. Although radioimmunoassay (RIA) is still considered as the reference technique for the measurement of T$_4$, it is generally regarded that RIA has its primary disadventages in handling the wastes and controling the human and material resources. Therefore, establishment of enzyme-linked immunosorbent assay (ELISA) has of great significance. To verify the usefulness of our enzyme immunoassay, we have obtained the standard dose response curve of T$_4$ in patient's sera which is inversely proportional to the amount of herseradish peroxidase (HRP) conjugated monoclonal antibody of T$_4$ bound to the wells. The correlation coefficient (r) between the ELISA and chemiluminescent assay was 0.444 (n=38). Thus we have investigated the establishment of rapid and sensitive competitive ELISA assay method for detection of T$_4$ in patient's sera.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.4
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• pp.336-341
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• 2016

This paper presents an implementation of a communication network in wind turbines, which exploits the power-line communication system (PLC). We used an inductive coupling unit and a multi-interface device to connect a data-communication terminal to the power line, to ensure that stable communication was possible at various electric current and voltage values of the generator. The results of the operation tests conducted on an operational wind turbine showed that the implemented PLC demonstrated a transmission rate of at least 43 Mbps with a 100% success rate. Moreover, a real-time image was transmitted. Thus, the system could be a useful alternative for implementing a communication network in wind turbines that does not require additional channels. Since the presented system is easy to implement, and can support various interfaces for data communication, it will be quite useful when a real-time monitoring system is launched in wind turbines.

• The Journal of Korean Medicine
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• v.39 no.1
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• pp.75-85
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• 2018

Objectives: This is a long-term survival case report about glioblastoma treated with western medicine and traditional Korean medicine. 28 year-old man diagnosed glioblastoma in 2003 went through 2 year's chemotherapy first. After emergency brain surgery he took acupuncture and Korean herbal medication including Dohongsamul-tang and Boan-Manyeongdan in addition to conventional radiotherapy and chemotherapy for 3 years. Since May 2008, he was exclusively treated with traditional Korean medicine except taking antiplatelets only for 9 years. Though he has sequelae of tumor necrosis such as facial palsy and hemiparesis, he has survived without recurrence more than 14 years. We suggest that integrative approach including traditional Korean medicine can be a meaningful treatment option for malignant brain tumor. Further studies with more cases should be performed to establish proper treatment protocol of integrative medicine for brain tumor.

• Composites Research
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• v.31 no.5
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• pp.282-287
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• 2018

In this paper, we explore interfacial properties of the mineralized CNTs when they are employed as reinforcing fillers in a polymer nanocomposite using molecular dynamics (MD) simulations. Recently, several studies on mineralizing carbon nanotubes (CNTs) with an aid of nitrogen doping to CNTs have been reported. However, there is a lack of studies on the reinforcing effects of the mineralized CNTs when it is employed as a filler of nanocomposites. Silica ($SiO_2$) is used as a mineral material and poly (methyl metacrylate) (PMMA) is used as a polymer matrix. Pull-out simulations are conducted to obtain the interfacial energy and the interfacial shear stress. It was found that the silica mineralized CNTs have higher interfacial interaction with the polymer matrix. In the future, by examining various thermomechanical properties of the mineralized-CNT-filler/polymer nanocomposites, we will search for potential applications of the novel reinforcing filler.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.135-140
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• 2004

Anti-skin aging agent could be have an inhibition effect of ROS production as well as fragmentation and change of collagen cross linkage in collagen molecule. For the monitoring of lipid peroxidation and collagen degradation, the skin of young and old rats were incised and observed 7 days. In the result, the wound closure was observed in the skin from 10 of 11 young rats and in 8 of 11 old rats. And the longer wound length but shorter wound closure, weaker collagen density and thicker epidermis were observed in old rats than in young rats. The level of hydroxyproline as a parameter of collagen synthesis and MDA as a parameter of lipid peroxidation was lower in old group than in young group. The cyst and lacuna between collagen bundle and fibroblast were observed in old rats in contrast to young rats. So that we propose that MDA and hydroxyproline could be used for monitoring of anti-skin aging agent.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.261-268
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• 1992

The membranes of mitochondria and chloroplasts contain a number of pigments that can act as endogenous sensitizers to produce activated oxygen species, most efficiently in blue light, which, in turn, attack functional targets in membranes. Therefore, intense blue light from the sun can exert various adverse effects on the functional and structural integrity of the membranes: one of the biochemical events of these negative effects could be the oxidative degradation of the unsaturated fatty acid constituents of membrane polar lipid. It may be assumed that as a strategy to avoid the light induced fatty acid degradation in membranes plant cells, responding to high intensity blue light, change the fatty acid compositions of membrane lipid in such that more-unsaturated fatty acid constituents are replaced by lessunsaturated fatty acid constituents. The results obtained in the present study, most importantly the measurements of double bond index of membrane polar lipid in concert with other measurements such as light quaility-dependent membrane peroxidation and the activities of membrane-bound proteins, seem to support this assumption.