• Geophysics and Geophysical Exploration
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• v.21 no.3
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• pp.150-161
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• 2018

Recently, unmanned aircraft EM (electromagnetic) survey based on ICT (Information and Communication Technology) has been widely utilized because of the efficiency in regional survey. We performed the theoretical study on the unmanned airship EM system developed by KIGAM (Korea Institute of Geoscience and Mineral resources) as part of the practical application of unmanned aircraft EM survey. Since this system has different configurations of transmitting and receiving loops compared to the conventional aircraft EM systems, a new technique is required for the appropriate interpretation of measured responses. Therefore, we proposed a method to calculate the EM field for the arbitrary shaped transmitter and verified its validity through the comparison with analytic solution for circular loop. In addition, to simulate the magnetic responses by three-dimensionally (3D) distributed anomalies, we have adapted our algorithm to 3D frequency-domain EM modeling algorithm based on the edge-FEM (finite element method). Though the analysis on magnetic field responses from a subsurface anomaly, it was found that the response decreases as the depth of the anomaly increases or the flight altitude increases. Also, it was confirmed that the response became smaller as the resistivity of the anomaly increases. However, a nonlinear trend of the out-of-phase component is shown depending on the depth of the anomaly and the used frequency, that makes it difficult to apply simple analysis based on the mapping of the magnitude of the responses and can cause the non-uniqueness problem in calculating the apparent resistivity. Thus, it is a prerequisite to analyze the appropriate frequency band and flight altitude considering the purpose of the survey and the site conditions when conducting a survey using the unmanned aircraft EM system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.2
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• pp.21-31
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• 2010

This paper presents a design of PLL and SSCG for reducing the EMI effect at the electronic machinery and tools for DisplayPort application. This system is composed of the essential element of PLL and Charge-Pump2 and Reference Clock Divider to implement the SSCG operation. In this paper, 270MHz/162MHz dual-mode PLL that can provide 10-phase and 1.35GHz/810MHz PLL that can reduce the jitter are designed for 2.7Gbps/162Gbps DisplayPort application. The jitter can be reduced drastically by combining 270MHz/162MHz PLL with 2-stage 5 to 1 serializer and 1.35GHz PLL with 2 to 1 serializer. This paper propose the frequency divider topology which can share the divider between modes and guarantee the 50% duty ratio. And, the output current mismatch can be reduced by using the proposed charge-pump topology. It is implemented using 0.13 um CMOS process and die areas of 270MHz/162MHz PLL and 1.35GHz/810MHz PLL are $650um\;{\times}\;500um$ and $600um\;{\times}\;500um$, respectively. The VCO tuning range of 270 MHz/162 MHz PLL is 330 MHz and the phase noise is -114 dBc/Hz at 1 MHz offset. The measured SSCG down spread amplitude is 0.5% and modulation frequency is 31kHz. The total power consumption is 48mW.

• Journal of agricultural medicine and community health
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• v.34 no.2
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• pp.175-187
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• 2009

Objectives: This study was conducted to investigate whether joint effects between family allergy history and environmental tobacco smoke(ETS) by parents were associated with pediatric asthma and wheezing. Methods: The study objects of this study were 2301 element school students and their parents in an urban-rural areas of Gyeonggi-do. Pediatric asthma and wheezing were identified by measures of International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires. We investigated history of parental allergy, ETS, and other socioeconomic status of both parent. Data were analyzed using logistic regression methods. Results: After adjusting other variables, children with maternal asthma history were more likely to be reported life time wheezing (OR: 3.79 95%CI:2.43-5.90), recent wheezing (OR:4.09 95%CI:2.28-7.38), and diagnostic asthma (OR:2.61 95%CI: 1.44-4.75). Paternal asthma history increasing risk of life time wheezing (OR 2.01 95%CI:1.19-3.38) and recent wheezing (OR:2.38 95%CI:1.24-4.56). Joint effect between parental allergy history and ETS significantly effected on child's life time wheezing and recent wheezing. The risks of life time wheezing (OR:2.47 95%CI:1.64-3.717) and recent wheezing (OR: 2.51 95%CI:1.34-4.69) were significantly higher than others without both factors. The risk of recent wheezing of children with maternal recent smoking and parental allergy history (OR:4.83 95%CI:1.89-12.33) was higher than their counterpart. Conclusions: The result of this study implies that children with family allergy history and passive smoking are more likely to be get asthma and wheezing than children with family allergy history and non-passive smoking. This study provide the object information to increase the efficiency of non-smoking campaign and education for decreasing pediatric asthma risk.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.324-332
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• 2011

Purpose: The purpose of this study was to compare the stress distribution of teeth and jaw on load by differentiating property of materials according to each layer of widely used mouthguard. Materials and methods: A Korean adult having normal cranium and mandible was selected to examine. A customized mouthguard was constructed by use of DRUFOMAT plate and DRUFOMAT-TE/-SQ of Dreve Co. according to Signature Mouthguard system. The cranium was scanned by means of computed tomography with 1mm interval. It was modeled with CANTIBio BIONIX/Body Builder program and simulated and interpreted using Alter HyperMesh program. The mouthguard was classified as follows according to the layers. (1) soft guard (Bioplast)(SG) (2) hard guard (Duran)(HG) (3) medium guard (Drufomat)(MG) (4) soft layer + hard layer (SG + HG) (5) hard layer + soft layer (HG + SG) (6) soft layer + hard layer + soft layer (SG + HG + SG) (7) hard layer + soft layer + hard layer (HG + SG + HG) The impact locations on mandible were gnathion, the center of inferior border, and the anterior edge of gonial angle. And the impact directions were oblique ($45^{\circ}$). The impact load was 800 N for 0.1 sec. The stress distribution was measured at maxillary teeth, TMJ and maxilla. The statistics were conducted using Repeated ANOVA and in case of difference, Duncan test was used as post analysis. Results: In teeth and maxilla, the mouthguard contacting soft layer of mandibular teeth presented lowest stress measure and, in contrast, in condyle, the mouthguard contacting hard layer of mandibular teeth presented lowest stress measure. Conclusion: For all impact directions, soft layer + hard layer + soft layer, the mouthguard with three layers which the hard layer is sandwiched between two soft layers, showed relatively even distribution of stress in impact.

• The Journal of the Petrological Society of Korea
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• v.20 no.1
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• pp.1-21
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• 2011

Eoil basalt in the Eoil basin and Yeonil basalt and its related volcanic rocks in Guryongpo and Daebo area were researched and analyzed to purse the tectonic settings and magma characteristics of those Tertiary volcanic rocks in the south-east Korean peninsula. It is highly suggested that zoning, resorption and sieve texture in plagioclase and reaction rim in pyroxene indicate unstable tectonic environments and complex volcanism in the study area. Volcanic rocks from Janggi basin are identified as basalt and basaltic andesite in TAS diagram and sub-alkaline series in terms of magma differentiation. $Na_2O$ and $K_2O$ show positive trend however FeO, CaO, MgO and $P_2O_5$ indicate negative trend in Harker variation diagram with $SiO_2$. Basaltic rocks from Eoil area are identified as calc-alkaline series in AFM diagram and show medium K series calc-alkaline in $K_2O-SiO_2$ diagram. Compatible trace elements of Co, Ni, V, Zn, and Sc in Yeonil basalt show negative trend with crystallization but incompatible trace element of Ba, Rb show positive trend with $SiO_2$ 0.81~1.00 of $Eu/Eu^*$ value suggests minor effect of plagioclase fractionation in Yeonil basaltic rocks. Plagioclase composition of Eoil basalt ranges from $An_{63.46-98.38}\;Ab_{1.62-32.96}\;Or_{0-3.58}$ (anorthite-labradorite) in core to $An_{40.89-82.44}\;Ab_{17.10-46.43}\;Or_{0-12.68}$ (bytownite-labradorite) in rim. $^{87}Sr/^{86}Sr$ and 143Nd;t44Nd ranges 0.704090~0.704717 and 0.512705~0.512822 respectively. Negative linear trends in 87Sr/86Sr and $^{143}Nd/^{144}Nd$ correlation diagram indicate that magma produced Yeonil basalt and basaltic andesite has been originated as partial melting product of mantle wedge by subducting Pacific plate affected by oceanic crust with less effect of continental crust indicating calc-alkaline magma characteristics.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.257-267
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• 2017

Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.301-308
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• 1982

Chungkook-jang Koji was fermented with rice straw at $40^{\circ}C\;and\;50^{\circ}C$ for 72 hours. The changes of proximate composition, pH, titrable acidity, nitrogen compounds, protease activity and free-amino acids during the fermentation were investigated. Moisture, lipid and protein contents remained essentially unchanged during the fermentation. The pH was gradually increased from 6.4 to 7.46 and 7.82 at $40^{\circ}C\;and\;50^{\circ}C$, respectively, after 72 hour fermentation. Amino type and water soluble nitrogen increased as fermentation progressed. however, the former slightly decreased after 60 hour fermentation. Chungkook-jang fermented at $40^{\circ}C$ showed somewhat higher protease activity than $50^{\circ}C$. However, protease activity at both fermentation temperatures showed the same trend; that is, it increased until 48 hour fermentation and thereafter decrease. Free amino acid content of Chung-kook-jang after 72 hour fermentation at $40^{\circ}C$ was 6 times greater than that of the steamed soybean, while it was 2.5 times greater at $50^{\circ}C$. Based on these results. it seems that the optimum fermentation conditions for Chungkook-jang were $40^{\circ}C$ and 72 hours.

• Journal of Life Science
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• v.17 no.11
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• pp.1562-1570
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• 2007

This experiment was conducted to develop fertilizer which promotes plant growth as well as suppressing pathogenic fungi. The fertilizer was made from the mixture of Ju-Back (Korean rice wine cake) and indigenous rhizosphere-bacterium. The main ingredients of Ju-Back were investigated as 6.04% total nitrogen, 42.59% total carbohydrate, 1.01% available phosphate, 73.42% organic matter, 7.72% potassium oxide, 1.35% calcium oxide, 0.53% magnesium oxide. The enzyme activities of Ju-Back were estimated to be 980 units/g for ${\alpha}-amylase$, 300 units/g for glucoamylase, and 1800 units/g for acid pretense. Indigenous rhizosphere bacteria which produced antifungal agent were isolated from soil, and was selected KMU-13 strain which can antagonize against various plant pathogenic fungi (Botrytis cinerea KACC 40573, Sclerotinia sclerotiorum KACC 41065, Fusairum oxysporum KACC 40052, Pythium aphanidermatum KACC 40156, Phytophthora capsici KACC 40476 and Glomerella cingulata KACC 40299). KMU-13 strain was identified as Bacillus subtilis KMU-13 by biochemical and 16s rDNA analysis. The organic fertilizer was made as prototype which was composed 20% Ju-Back, 70% carrier, 9.7% microorganism cultivated solution, 0.3% trace-element. We also investigated an application of fertilizer using Ju-Back for cultivating lettuce (Lactuca sativar) which were grown in three soil conditions that had chemical fertilizer, barnyard manure, lime power, urea, potassium chloride and superphosphate as a control, the whole quantity (80 kg/10a) of posted fertilizer with the control and the half quantity (40 kg/10a) with the control. The growth characteristics were examined and analysed with several weeks interval from 3 weeks to 8 weeks on head length (cm), head width (cm/head), number of leaf and fresh weight (g/plant). The results are summarized as follows. The head width and fresh weight of lettuce were the highest at posted fertilizer 1 (whole quantity) was applied chemical, organic matter (Ju-Back) and carrier. The head length was the highest at posted fertilizer 2 (whole quantity) was applied Ju-Back only.

• Journal of Life Science
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• v.20 no.7
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• pp.1054-1065
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• 2010

SH21B is a natural composition composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). In our previous study, we reported that SH21B inhibited adipogenesis and fat accumulation in 3T3-L1 cells through modulation of various regulators in the adipogenesis pathway. The aim of this study was to analyze the transcriptome profiles for the anti-adipogenic effects of SH21B in 3T3-L1 cells. Total RNAs from SH21B-treated 3T3-L1 cells were reverse-transcribed into cDNAs and hybridized to Affymetrix Mouse Gene 1.0 ST array. From microarray analyses, we identified 2,568 genes of which expressions were changed more than two-fold by SH21B, and the clustering analyses of these genes resulted in 9 clusters. Three clusters among the 9 showed down-regulation by SH21B (cluster 4, cluster 6 and cluster 9), and two clusters showed up-regulation by SH21B (cluster 7 and cluster 8) during the adipogenesis of 3T3-L1 cells. It was found that many genes related to cell proliferation and adipogenesis were included in these clusters. Clusters 4, 6 and 9 included genes which were related with adipogenesis induction and cell cycle arrest. Clusters 7 and 8 included genes related to cell proliferation as well as adipogenesis inhibition. These results suggest that the mechanisms of the anti-adipogenic effects of SH21B may be the modulation of genes involved in cell proliferation and adipogenesis.

• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.126-135
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• 2002

Plate bonding technique has been widely used in strengthening of existing concrete structures, although it has often a serious problem of premature falure such as interface separation and rip-off. However, this premature failure problem has not been well explored yet especially in view of local failure mechanism around the interface of plate ends. The purpose of the present study is, therefore, to identify the local failure of strengthened plates and to derive a separation criterion at the interface of plates. To this end, a comprehensive experimental program has been set up. The double lap pull-out tests considering pure shear force and half beam tests considering combined flexure-shear force were performed. The main experimental parameters include plate thickness, adhesive thickness, and plate end arrangement. The strains along the longitudinal direction of steel plates have been measured and the shear stress were calculated from those measures strains. The effects of plate thickness, bonded length, and plate end treatment have been also clarified from the present test results. Nonlinear finite element analysis has been performed and compared with test results. The Interface properties are also modeled to present the separation failure behavior of strengthened members. The cracking patterns as well as maximum failure loads agree well with test data. The relation between maximum shear and normal stresses at the interface has been derived to propose a separation failure criterion of strengthened members. The present study allows more realistic analysis and design of externally strengthened flexural member with steel plates.