• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1471-1475
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• 2004

Thuja orientalis extract (TOS) has been used on the hemostatic roborant, sedatives and stressless in oriental countries. We investigate the inhibitory effects on the productions of pro-inflammatory cytokines such as interleukin-1beta (IL-1β), IL-6, tumour necrosis factor alpha (TNF-α), and nitric oxide (NO) and the hair promotiont of TOS in the macrophage celline RAW264.7 or hair loss-induced DBA1J mice. T08 (50-500 ㎍/㎖) per se had no cytotoxic effect non-stimulated cells, but this extracts concentration-dependently reduced the release of NO, (IL-1β), IL-6, and TNF-α in the stimulate RAW264.7 cells with lipopolysaccharide (LPS). Moreover, when applied TOS (500 ㎍/㎖) to DBA 1J/mice, hair growth was promoted remarkably. These data suggest that T08 promotes hair growth on hair loss induced model mice and these properties may contribute to the anti- hair loss activity of the Thuja orientalis.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.210-217
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• 1999

Chemical oxygen demand (COD), phytoplankton cell number and chlorophyll-a concentration (Chl-a), sediment mean grain size and ignition loss were studied to determine their temporal trends in the study area. Historical data of COD, cell number and Chl-a were gathered from the late 1960s or early 1980s to 1997, and trends in temporal domain were obtained from a simple regression. Sediments for grain size and ignition loss (as organic contents in sediments) were sampled from the Chokchon macrotidal flat bimonthly from September 1990 to November 1996, and were analyzed using the decomposition method of time series analysis. In general, the first three data showed increasing trends based on regression analysis. The trends of sediment grain size fluctuated in a neutral pathway while those of ignition loss yielded no increasing pattern. In contrast with the suggestions from Ahn and Choi (1998) who reported a coarsening variation in sediment grain size to be a cause of the directional and remarkable changes of macrofaunal communities in this area, we could not find such a corresponding variation pattern from our samples. In diagnosing eutrophication, a paradoxical phenomenon was encountered between the trends in water column (COD, cell number and Chl-a) and sediment (ignition loss) data. In this paper, we inferred the possible processes that produce the discrepancy. Some explanations and biological responses to eutrophication were predicted and discussed.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.3
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• pp.287-297
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• 1994

The purpose of this study is to investigate the Improvement of fiber surface, tenacity & elogation, fabric counts, thickness, handle, moisture regain, static voltage, handle, dyeability when polyester fabrics are treated with NaOH solution adding quartemary ammonium salt (Benzyl dimetyl dodecyl ammonium chloride . BDMDAC) The results are as follows. I. In regard to the method of processing VET, when the PET fabrics are alkaline-hydrolyzed adding BDMDAC, the weight loss of PET fabrics increased remarkably to the increse of BDMDAC concentration than when they are treated only in NaOH solution. When PET fabrics are alkaline-hydrolyzed the amount of BDMDAC as the catalyst is proper lg/1 II. The change in physical & chemical properties of alkaline-hydrolyzed PET fabrirs. 1. As the amount of the weight loss on PET fabrics increased, the void space of the PET yale increased but tenacity & elongation and thickness decreased. 2. The fabric counts of PET increased due to shrinkage by alkaline-hydrolydzing. 3. As the amount of of the weight loss on PET fabrics increased. NUMERI, FUKURAMI, increaseed and KOSHI decreased and Total hand value(T.H.V) in all cases increaseed. When the weight Ioss is 30.9% T.H.V. is best. 4. Moisture regain of PET fabrics a little increased by alkaline-hydrolyzing treatment. As the weight loss increased, static voltage is decreased. 5. The last dye absorption is different according to the degree of the Affinity. In regard to the difference of dye color, the dyestuff of low molecular weight dyed for deep color.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.6
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• pp.685-692
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• 2003

A numerical simulation of flame propagation in a micro combustor was carried out. Combustor has a sub -millimeter depth cylindrical internal volume and axisymmetric one-dimensional was used to simplify the geometry. Semi-empirical heat transfer model was used to account for the heat loss to the walls during the flame propagation. A detailed chemical kinetics model of $H_2/Air$ with 10 species and 16 reaction steps was used to calculate the combustion. An operator-splitting PISO scheme that is non-iterative, time-dependent, and implicit was used to solve the system of transport equations. The computation was validated for adiabatic flame propagation and showed good agreement with existing results of adiabatic flame propagation. A full simulation including the heat loss model was carried out and results were compared with measurements made at corresponding test conditions. The heat loss that adds its significance at smaller value of combust or height obviously affected the flame propagation speed as final temperature of the burnt gas inside the combustor. Also, the distribution of gas properties such as temperature and species concentration showed wide variation inside the combustor, which affected the evaluation of total work available of the gases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.6
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• pp.538-548
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• 2003

We studied effects by Re$_2$O$_3$(R=Dy, Gd, Ho) addition on the properties of Mn-Zn ferrite. The doping concentration range from 0.05 wt% to 0.25 wt%. All samples were prepared by standard fabrication of ceramics. With increasing the rare earth oxides, specific density and initial permeability increased on the whole. But, the tendencies such as upper result had the measured value on limitation and characteristics saturated or decreased properties after that. In case of excessive addition of additive beyond some level, initial permeability properties of ferrite have gone down in spite of anomalous grain. With increasing the content of additive, both the real and imaginary component of complex permeability and the magnetic loss (tan$\delta$) increased. Because the increased rate of real component had higher than imaginary component, magnetic loss increased none the less for increasing the real component related with magnetic permeability. But, the magnetic loss of ferrite doped with the rare earth oxides was lower than that of Mn-Zn ferrite at any rate. The small amount of present rare earth oxides in Mn-Zn ferrite composition led to enhancement of resistivity in bulk, and more so in the grain boundary. It was seem to be due to the formation of mutual reaction such as between iron ions and rare earth element ions.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.10-19
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• 1993

Broad, mercerized broad, mercerized twill cotton fabrics and rayon fabric were treated with cellulase for 30~480 minutes at different temperature, concentration, time, and also treating methods such as continuously-treated or repeatedly-treated, and dyed with two direct dyes before or after enzyme treatment. From the experimental result by treating under the various conditions above, it was obtained that the weight loss increased more in thin fabric than thick one. In addition, it was considered that the treatment in 5$0^{\circ}C$ for 240 minutes brought about the ideal weight loss and flexible hand of the specimens. For both broad and mercerized broad, repeated treatment showed more weight loss than continuous. Direct dye on cotton fabric apparently inhibited hydrolysis. Ionic surfactants showed the inhibition effect of the catalytic hydrolysis of enzyme, on the other hand, nonionic surfactant did not.

• Journal of the Korean Ceramic Society
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• v.42 no.12 s.283
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• pp.854-859
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• 2005

Performance of micro scale intermediate temperature solid oxide fuel cell system has been successfully evaluated by computer simulation based on macro modeling. Two systems were studied in this work. The one is designed that the ceria-based electrolyte placed between composite electrodes and the other is designed that electrodes alternately placed on the electrolyte. The injected gas was composed of hydrogen and air. The polarization curve was obtained through a series of calculations for ohmic loss, activation loss and concentration loss. The calculation of each loss was based on the solving of mathematical model of multi physical-phenomena such as ion conduction, fluid dynamics and diffusion and convection by Finite Element Method (FEM). The performance characteristics of SOFC were quantitatively investigated for various structural parameters such as distance between electrodes and thickness of electrolyte.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.372-376
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• 1998

Internal mass transfer during osmotic dehydration of gingers in sugar solution was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration on browning reaction and texture properties of air dried rehydrated was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in the first 3 min and then changed gentle slope. Moisture loss during osmotic dehydration using a sugar solution $(60\;Brix,\;80^{\circ}C)$ with 18 min immersion time was 40.05 g moisture/100 g wet ginger which was 52% reduction of initial moisture content in ginger (83.02%, wet basis). The changes of rate parameter were more affected by temperature than by concentration of sugar solution. Minimum browning degree (O.D.=0.027) was carried out by osmotic dehydration in sugar solution $(40\;or\;50\;Brix,\;80^{\circ}C)$ with 15 min immersion time compared to control (O.D.=0.132). Influence of osmotic dehydration on puncture forces of 3 min rehydrated ginger in boiling water were $22{\sim}34%$ of reduction, while blanching treatment had not affected compared to those of control.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2720-2724
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• 2007

Field measurements have revealed that the pressure drop over a borehole during drilling of a slim oil well or a well with a long reach can depend significantly on the rotation speed of the drill pipe. An accurate prediction of the annular frictional pressure drop is therefore important for conditions where the annular clearance is small. An experimental study was carried out to study solid-liquid two phase flow in a slim hole annulus. Annular velocities of carrier fluids varied from 0.2 m/s to 1.5 m/s. The carrier fluids which were utilized included tap water and CMC water solutions. Pressure drops and average flow rates were measured for the parameters such as inner-pipe rotary speed, carrier fluid velocity, hole inclination and particle injection rate. For both water and CMC solutions, the higher the concentration of the solid particles is, the larger the pressure gradients become.

• Journal of the Korean Society of Safety
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• v.28 no.2
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• pp.42-48
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• 2013

The $CO_2$ suppression characteristics and flame structure of nitrogen-diluted methane counterflow non-premixed flame were studied experimentally and numerically. To mimic a situation where combustion product gases are entrained into a compartment fire, fuel stream was diluted with $N_2$. A gas-phase suppression agent, $CO_2$, was diluted in the air-stream to investigate the suppression characteristics by the agent. For numerical simulation, an one-dimensional OPPDIF code was used for comparison with experimental results. An optically-thin radiation model(OTM) was adopted to consider radiation effects on the suppression characteristics. It was confirmed experimentally and numerically that suppression limit decreased with increasing nitrogen mole fraction in the fuel stream. A turning point was found only when a radiation heat loss was considered and the extinguishing concentration for turning point was differently predicted compared to the experiment result. Critical extinguishing concentration when neglecting radiation heat loss was also differently predicted compared with the experimental result.