• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.387-388
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• 2008

In this paper, we have designed and fabricated hyperabrupt varactor diodes. Capacitance variations of hyperabrupt-doped varactor diodes are larger than those of uniform-doped varactor diodes. The measured reverse breakdown voltage of the fabricated varactor diodes was about 20 V. For the anode contact diameter of $50\;{\mu}m$, the maximum capacitance of the fabricated varactor diode was 2.1 pF and the minimum capacitance 0.44 pF. Therefore, the $C_{max}/C_{min}$ ratio was 4.77. Also, for the anode contact diameter of $60\;{\mu}m$, the maximum and minimum capacitances were 2.9 and 0.62 pF, respectively. And, thus, the $C_{max}/C_{min}$ ratio was 4.64.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.163-173
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• 2003

Research objective:To exactly evaluate their functions of kojic acid, arbutin and vitamin C as a whitening agent, we performed experiments to compare their abilities to inhibit melanin synthesis. Experimental methods and techniques: The effects of kojic acid, arbutin and vitamin C on cell viability and melanin synthesis were evaluated by the level of melanin content and the number of viable cells upon treatment of them.

• Proceedings of the Korean Vacuum Society Conference
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• 2005.08a
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• pp.52-52
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• 2005

• Natural Product Sciences
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• v.24 no.4
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• pp.266-271
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• 2018

Five new prenylated stilbenes (1 - 5), along with the known compounds cudraflavone C, trans-4-isopentenyl-3,5,2',4'-terahydroxystilbene, trans-4-(3-methyl-E-but-1-enyl)-3,5,2',4'-tetrahydroxystilbene, pannokin G, cycloartobiloxanthone, artonin P, morusin, artocarpin, artonin E, kuwanon C, artobiloxanthone, and artoindonesianin C (6 - 17) were isolated from the stem bark of the tropical tree Artocarpus communis. The structures were established by NMR spectroscopic analysis, MS studies, and comparison with spectral data reported in the literature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1280-1285
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• 2006

The presoaking conditions of soybeans in various solution for decreasing microbial contamination and improving germination were investigated. Soybeans were treated with presoaking solutions (sterilized water, 0.1% grape fruit extract, 0.1% vitamin $B_1$ derivate solution AS5 and vitagen) at $25^{\circ}C,\;35^{\circ}C,\;45^{\circ}C\;and\;55^{\circ}C$ for $3\sim12$ hr and germinate at $25^{\circ}C$, 95%RH for 3 days. Total bacterial count and coliform count of soybeans were $6.0\times10^5CFU/g$ and $3.0\times10^5CFU/g$, respectively, and the most of presoaking treatments decreased the microbial contamination. The increase of presoaking time induces low germination ratio compared with unsoaked soybeans and the germination of soybeans was not detected at $55^{\circ}C$. The germination of soybeans was effected by presoaking solutions, temperature, and time. The optimal presoaking condition for decreasing microbial contamination and promoting initial germination was using grape fruit extract at $35^{\circ}C$ for 6 hr.

• Mass Spectrometry Letters
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• v.2 no.2
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• pp.33-36
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• 2011

The misuse of anabolic androgenic steroids is of particular concern in sports and society. Thus, it is of great importance to discriminate endogenous steroids such as testosterone or testosterone prohormones from their chemically identical synthetic copies. In this study, gas chromatography-combustion/isotope ratio mass spectrometric (GC-C/IRMS) method has been developed and validated for discriminating the origin of anabolic androgenic steroids. The method involves the solid-phase extraction, enzymatic hydrolysis with ${\beta}$-glucuronidase, HPLC-fractionation for the cleanup and analysis by GC-C/IRMS. The difference(${\Delta}^{13}C$) of urinary ${\delta}^{13}C$ values between synthetic analogues and endogenous reference compounds (ERC) by GC-C/IRMS was used to elucidate the origin of steroids, and intra- and inter-day precision, specificity and isotope fractionation were evaluated. The present GC-C/IRMS method combined with HPLC cleanup was accurate and reproducible enough to be successfully applied to the test of urine sample from suspected anabolic steroid abusers.

• Journal of Preventive Medicine and Public Health
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• v.40 no.4
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• pp.329-335
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• 2007

Objectives : To identify the effects of supplemental private health insurance on health care utilization and expenditure under the mandatory National Health Insurance(NHI) system in Korea. Methods : The data were collected by the National Cancer Center in Korea. Cancer patients who were newly diagnosed with stomach (ICD code, C16), lung(C33-C34), liver (C22), colorectal cancer(C18-C20) or breast(C50) cancer were included as study subjects. Data were gathered using a structured questionnaire from face-to-face interviews, the hospital Order Communication System (OCS) and medical records. Clinical, socio-demographic and private health insurance related factors were also gathered. The differences of health care utilization and expenditure were compared between those who have private health insurance and those who do not using t-test and multivariable regression analysis. Results : Individuals with private health insurance spent larger inpatient costs than those without, but no differences were found in utilization in other service such as hospital admissions, hospital days and physician visits. Conclusions : We found that private health insurance exerts a significant effect on the health care expenditure in inpatient service. These study results can provide a rational basis to plan a national health policy regarding private health insurance. Further studies are needed to investigate the impacts of private health insurance on cancer patients' outcomes and survival rates.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2012.07a
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• pp.97-100
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• 2012

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.5
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• pp.216-220
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• 2010

Ni-Fe alloys have various applications such as thin film inductor, thin film transformer, magnetic head's shield case, etc. Magnetic properties of Ni-Fe thin films depend on the process parameters such as thickness, contents, deposition rate, substrates, etc. In this study, NiFe films with a thickness of about 150nm were deposited on Si(100) wafer and $SiO_2$/Si(100) substrate at room temperature by a DC magnetron co-sputtering using Fe and Ni targets. Their phase formation and magnetic properties as a function of annealing temperature were investigated with XRD, FE-SEM and VSM. The assputtered films have BCC structure. With increasing annealing temperature, NiFe thin film for $SiO_2$/Si(100) substrate transformed completely from BCC to FCC phase above $500^{\circ}C$, but some BCC phase remained above $500^{\circ}C$ on Si(100) wafer. For samples annealed at $450^{\circ}C$, squareness ratio of NiFe thin film shows peak value and its saturation magnetization is around 0.0118 emu, which means that the optimum annealing temperature of NiFe thin film seems to be $450^{\circ}C$. The saturation magnetization of films decreased rapidly above the annealing temperature of $500^{\circ}C$ due to phase transformation from BCC to FCC phase.

• Molecules and Cells
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• v.38 no.1
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• pp.40-50
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• 2015

In the interaction between plants and pathogens, carbon (C) resources provide energy and C skeletons to maintain, among many functions, the plant immune system. However, variations in C availability on pathogen associated molecular pattern (PAMP) triggered immunity (PTI) have not been systematically examined. Here, three types of starch mutants with enhanced susceptibility to Pseudomonas syringae pv. tomato DC3000 hrcC were examined for PTI. In a dark period-dependent manner, the mutants showed compromised induction of a PTI marker, and callose accumulation in response to the bacterial PAMP flagellin, flg22. In combination with weakened PTI responses in wild type by inhibition of the TCA cycle, the experiments determined the necessity of C-derived energy in establishing PTI. Global gene expression analyses identified flg22 responsive genes displaying C supply-dependent patterns. Nutrient recycling-related genes were regulated similarly by C-limitation and flg22, indicating re-arrangements of expression programs to redirect resources that establish or strengthen PTI. Ethylene and NAC transcription factors appear to play roles in these processes. Under C-limitation, PTI appears compromised based on suppression of genes required for continued biosynthetic capacity and defenses through flg22. Our results provide a foundation for the intuitive perception of the interplay between plant nutrition status and pathogen defense.