• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.322-328
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• 2006

Green tea is of particular source as it has been found to have strong antioxidant activities. The extracts of green tea during the commercial harvest seasons from April, 2003 to August, 2003 were compared. The purpose of this study was to determine the correlation between the polyphenol content of green teas and its antioxidant activities. The con-tent of total polyphenols was analyzed and several antioxidant testings were performed. The levels of total polyphenols were higher in the green teas (e.g. Woojeon, Sejak) harvested during very early spring and lower in the green teas harvested late(eg. Ipha, Yepcha). In particular, the free radical scavenging, the inhibition of LDL oxidation, the cytoprotective effect and the inhibition of DNA damage were correlated with the total polyphenol contents of green tea extracts harvested early spring such as Woojeon, Sejak and Jungjak. The results obtained here show that all extracts of green teas including purified green tea catechin, GTC, have strong antioxidant activities on oxidative stress in vifrθ. The variation in polyphenol content and antioxidant activities among various types of green tea by the harvesting time may provide critical information for investigators and consumers using tea in purposes of nutrition and chemoprevention.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.7
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• pp.112-119
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• 2009

The purpose of this study is to evaluate the evaluation of process yield performed by using Sn & Cu treatment on the surface to optimize process condition for Lead-free solder application. The materials which are used for the New Surface Treatment study are Semi-Dulling plating for high speed Sn/Cu alloy of Soft Alloy GTC-33 Pb free known as "UEMURA Method" and plating substrate is alloy 42.Especially in lead-free plating process, it is important to control plating thickness and Copper composition than Sn/Pb plating. Evaluated and controlled plating thickness $12{\pm}3um$, Copper composition $2{\pm}1%$, plating particle and visual inspection. The optimization of these parameters and condition makes it makes possible to apply Sn/Cu Lead-free solder from Sn/Pb alloy.

• Journal of Powder Materials
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• v.23 no.1
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• pp.26-32
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• 2016

Powder injection molding (PIM), which combines the advantages of powder metallurgy and plastic injection molding technologies, has become one of the most efficient methods for the net-shape production of both metal and ceramic components. In this work, plasma display panel glass bodies are prepared by the PIM process. After sintering, the hot isostatic pressing (HIP) process is adopted for improving the density and mechanical properties of the PIMed glass bodies. The mechanical and thermal behaviors of the prepared specimens are analyzed through bending tests and dilatometric analysis, respectively. After HIPing, the flexural strength of the prepared glass body reaches up to 92.17 MPa, which is 1.273 and 2.178 times that of the fused glass body and PIMed bodies, respectively. Moreover, a thermal expansion coefficient of $7.816{\times}10^{-6}/^{\circ}C$ is obtained, which coincides with that of the raw glass powder ($7.5-8.0{\times}10^{-6}/^{\circ}C$), indicating that the glass body is fully densified after the HIP process.

• Journal of Pharmaceutical Investigation
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• v.29 no.2
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• pp.99-103
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• 1999

Self-Emulsifying System(SES), an isotropic mixture of oil and surfactant which forms oil-in-water emulsion, is expected to improve in vitro drug dissolution and enhance in vivo drug absorption. A poorly water soluble drug, ibu-profen(IBP) was incorporated into the SES to improve absorption, and enhance bioavailability of drug. Medium chain triglyceride, glyceryl tricaprylate(GTC) as an oil, and Tween 85 as a surfactant were used to formulate SES. To characterize SESs with various concentrations of Tween 85, the phase separation and solubility of IBP-SEDDS containing IBP as a function of Tween 85 concentration were conducted, and the particle size was measured using photon correlation spectroscopic method. The SES with optimal concentration of Tween 85(35%(w/w)) was selected based on its high drug loading, small particle size and low surfactant concentration. After an oral administration of IBP-SEDDS and IBP suspension in methyl cellulose equivalent to 40.0 mg/kg to rats, the pharmacokinetic parameters were compared. The $C_{max}(163.17\;vs\;88.82\;{\mu}g/ml)$, $AUC(12897.01\;vs\;8751.13\;{\mu}g\;min/ml)$ and Bioavailability(86.44 vs 58.65%) significantly increased but $T_max(10\;vs\;20\;min)$ was significantly advanced. The current SEDDS containing IBP provide an alternative to improve an oral bio-availability of IBP.

• KCI Concrete Journal
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• v.14 no.4
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• pp.151-159
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• 2002

This study investigates experimentally the optimum mix proportion and design factors of the stabilizing liquid used for excavation of the massive and deep slurry wall in LNG in-ground tank before pouring concrete. Considering those site conditions, the stabilizing liquid used for excavation of slurry wall has to be satisfied with some requirements including specific gravity, fluid loss, cake thickness, funnel viscosity and sand content in order to construct the safe and qualified slurry wall. For this purpose, we select materials including bentonite, polymer and dispersion agent. After performing many tests for materials and mix design process, we propose the optimum mix proportion that the upper limit ratio of bentonite is $2.0\%$, polymer is $0.1\%$ considering the funnel viscosity and dispersion agent is $0.05\%$considering the fluid loss of the stabilizing liquid. Also, we select all materials which are consisted of GTC4 as bentonite, KSTP as polymer and Bentocryl 86 as dispersion agent. Based on the results of this study, the optimum mix proportion of the stabilizing liquid is applicable to excavate the deep and massive slurry wall in LNG in-ground tank successfully.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.73.3-73.3
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• 2019

The AGN unification model suggested the presence of obscuring material, a dusty torus, to explain the various types of AGN. IR SED model fitting is a crucial tool to probe the structure and properties of the dusty torus. We use a sample of 16 local quasi-stellar objects in Martinez-Paredes et al. (2017) with obtained NIR and MIR high-angular resolution (~0.3") imaging data from EMIR, CIRCE and CanariCam on the 10.4-m Gran Telescopio CANARIAS (GTC) while 4 objects have NIR high-angular resolution photometry from NICMOS/HST from the literature. The unresolved NIR emission from the NIR image analysis and low-resolution Spitzer/IRS spectra are used to construct NIR-MIR SEDs covering a larger spectral range. We investigate the sensitivity of the geometrical (e.g. viewing angle) and physical parameters (e.g. optical depth) of the clumpy dusty torus model of Nenkova et al. and the clumpy disk+outflow model of Hoenig et al. We aim to investigate the minimal dataset needed to well constrain the parameters of the models and derive the properties of the dusty torus. These results will allow us to plan future observations for a larger sample of high luminosity AGNs with the James Webb Space Telescope and the Giant Magellan Telescope.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.510-513
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• 2003

Duplication of chromosome 7q has been reported as either partial or complete. Partial 7q duplication was first described by Carpentier in 1972. Pure partial duplication of the long arm of chromosome 7 is extremely rare and only 16 cases with a pure partial duplication of different 7q segment have been described in the literature. Pure partial duplication of the long arm of chromosome 7 is characterized by growth and developmental retardation, muscular hypotonia, distinct craniofacial dysmorphic features, a short neck and skeletal abnormalities. A 3 month-old male was referred to our department of Pediatrics because of dyspnea, hypotonia and delayed development. He shows growth and developmental delay, hypertelorism, a depressed nasal bridge, low set ears, a short neck and muscular hypotonia. Karyotype revealed 46, XY, dup(7)(q36q33) by GTC-banding. We report a case of a partial inverted duplication of chromosome 7q.

• Journal of Energy Engineering
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• v.20 no.2
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• pp.123-142
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• 2011

Coal Gasification Technology is one of the best alternatives among clean fossil fuel utilization. Major technology holding companies are devoting their efforts to develop more advanced technology to dominate the market in advance because of its importance on the applications such as IGCC, CTL, coal to SNG, various chemicals and so on. Japan and China, as well as America and European countries, have developed couple of thousands ton/day-class coal gasification technology. However, our gasification technology remains in the development stage with couple of ton/day-class pilot plant. So, we should be interested in developing this technology considering that we are heavily dependent of coal energy. In this paper, we summarized the trend and status of coal gasification technology development and commercial deployment of major technology holding companies mainly from the presentation materials of 'Gasification Technology Conference 2010', which is the biggest place of information exchange for recent coal gasification technology.

• The Journal of Korean Society for Radiation Therapy
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• v.9 no.1
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• pp.25-28
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• 1997

With the advances in radiation therapy technology and equipment, the need for more accurate and safer radiation delivery to the target region has been continuously growing. Stereotactic Radiosurgery(SRS) is a good example of $^{\ast}Accuracy^{\ast}$ but has a substantial risk of causing severe late neurological damages. Fractionated Stereotactic Radiation Therapy(FSRT) is a modification of SRS enabling conventional fractionation with maintaining accuracy using noninvasive and relocatable frame. Verification of mechanical accuracy in FSRT has been done according to the manufacture's recommendations using RLPP, LTLF, and Depth-helmet. In order to reinforce this, we have developed additional novel verification procedure using Linac-grams with the Angiolocalizer attached on the GTC frame, which are then digitized into the planning software(X-Knife) to generate the three dimensional coordinates for cmoparison. This method has been successful in such ways that the anatomical landmarks are identifiable on the Linac-gram films and that the serial comparisons of the stereotactic coordinates of the isocenter are possible with more certainty a along the FSRT course than before.

• The KIPS Transactions:PartD
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• v.13D no.2 s.105
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• pp.175-182
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• 2006

Radars are used to detect the motion of the low flying enemy planes in the military. Radar-detected raw data are first processed and then inserted into the ground tactical C4I system. Next, these data we analyzed and broadcasted to the Shooter system in real time. But the accuracy of information and time spent on the displaying and graphical computation are dependent on the operator's capability. In this paper, we propose the Flying Object Tracking Management System that allows the displaying of the objects' trails in real time by using data received from the radars. We apply the coordinate system translation algorithm, existing communication protocol improvements with communication equipment, and signal and information computation process. Especially, radar signal duplication computation and synchronization algorithm is developed to display the objects' coordinates and thus we can improve the Tactical Air control system's reliability, efficiency, and easy-of-usage.