• Journal of Institute of Convergence Technology
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• v.4 no.1
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• pp.21-27
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• 2014

White LEDs (light-emitting diodes) are promising new-generation light sources which can replace conventional lamps due to their high reliability, low energy consumption and eco-friendly effects. This paper briefly reviews recent progress of oxy/nitride host phosphor and quantum dot materials with broad excitation band characteristics for phosphor-converted white LEDs. Among oxy/nitride host materials, $M_2Si_5N_8:Eu^{2+}$, $MAlSiN_3:Eu^{2+}$ M-SiON(M=Ca, Sr, Ba), ${\alpha}/{\beta}-SiAlON:Eu^{2+}$ are excellent phosphors for white LED using blue-emitting chip. They have very broad excitation bands in the range of 440-460 nm and exhibit emission from green to red. In this paper, In this review we focus on recent developments in the crystal structure, luminescence and applications of the oxy/nitride phosphors for white LEDs. In addition, the application prospects and current trends of research and development of quantum dot phosphors are also discussed.

• The Korean Journal of Food & Health Convergence
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• v.5 no.2
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• pp.27-34
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• 2019

RNases plays a pivotal role in biological system and different RNases are known for their various functions like angiogenesis, immunological response, antiviral, antitumour activity and apoptosis. In which anti tumour activity of RNase is proved to improve genome stability in normal cells up to some extent. RNases like RNase L shows antiviral and antitumour activities against virus infected cells and cancer cells through 2'-5' oligo adenylate pathway and induces RNaseL dependent apoptosis where as RNase A modulates various proliferative pathways like MAP kinase, JNK, TGF-${\beta}$ and activates apoptosis in cancer cells and promotes immunological response through processing of Ags. IRE1 RNase acts as both tumour suppressor gene and oncogene in normal and cancer cells and involved in both antitumour and tumorigenic activities. RNase III upregulates miRNA in cancer cells there by acting via posttranscriptional level and proven to be effective against colorectal adeno carcinoma. In addition to this IRE1 RNase is a double edged sword through RIDD pathway in ER (18). To some of the cancers expressing c-myc IRE1 acts as tumour suppressor where as in cancers where myc is downregulated IRE1 acts as tumour provoking through RIDD pathway (18). Thus RNases play vital role in regulating the genome stability.

• Journal of Microbiology and Biotechnology
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• v.33 no.1
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• pp.114-122
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• 2023

A family of signal transduction pathways known as wingless type (Wnt) signaling pathways is essential to developmental processes like cell division and proliferation. Mutation in Wnt signaling results in a variety of diseases, including cancers of the breast, colon, and skin, metabolic disease, and neurodegenerative disease; thus, the Wnt signaling pathways have been attractive targets for disease treatment. However, the complicatedness and large involveness of the pathway often hampers pinpointing the specific targets of the metabolic process. In our current study, we investigated the differential metabolic regulation by the overexpression of the Wnt signaling pathway in a timely-resolved manner by applying high-throughput and un-targeted metabolite profiling. We have detected and annotated 321 metabolite peaks from a total of 36 human embryonic kidney (HEK) 293 cells using GC-TOF MS and LC-Orbitrap MS. The un-targeted metabolomic analysis identified the radical reprogramming of a range of central carbon/nitrogen metabolism pathways, including glycolysis, TCA cycle, and glutaminolysis, and fatty acid pathways. The investigation, combined with targeted mRNA profiles, elucidated an explicit understanding of activated fatty acid metabolism (β-oxidation and biosynthesis). The findings proposed detailed mechanistic biochemical dynamics in response to Wnt-driven metabolic changes, which may help design precise therapeutic targets for Wnt-related diseases.

• Journal of the Korean Society of Food Culture
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• v.30 no.2
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• pp.197-205
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• 2015

This study was conducted to investigate the bioconversion of ginsenosides as well as anti-inflammatory activities of fresh ginseng Kkakdugi during fermentation. Fresh ginseng Kkakdugi reached proper ripeness, pH 4.30, and acidity 1.69% at $15^{\circ}C$ after 10 days. Lactic acid bacteria grew until reaching $1.10{\times}10^9CFU/mL$ after 20 days of fermentation, and ${\beta}$-glucosidase activity increased from 1.154 to 1.885 units/g. The bioconversion of ginsenosides was confirmed based on increased content of Rg3, an aglycone, from 0.13 to 0.17 mg/g during fermentation through HPLC. Fresh ginseng Kkakdugi did not display cytotoxicity up to the concentrations of $80{\mu}g/mL$, regardless of ripening period. Nitrite production and expression of inflammation-related proteins, iNOS and COX-2, decreased in a dose-dependent manner regardless of ripening period. From these results, fresh ginseng Kkakdugi showed the bioconversion of ginsenosides to aglycone during the lactic acid fermentation as well as an anti-inflammatory effect through the reduction of NO production and iNOS and COX-2 expression.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.509-515
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• 2015

This study verified the effectiveness of various economic experience in adolescence on forming economic view. Survey was carried out for Asan-si residents and online homepage visitors in Sep. 2015, 116 cases were finally used for analysis. This study confirmed the moderating effect of interest in economy on the relationship between various economic experience in adolescence and formation of economic view, and analyzed differences depend on economic knowledge learning path. Various economic experience in adolescence positively affected economic comprehension, rational consumption attitude, start-up intention and the moderating effect of interest in the economy was verified. Demographic Characteristics and economic knowledge learning path also affected differences of economic view by the group. These study results suggest that experiential youth economic education program will be effective on forming economic view.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.11
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• pp.854-858
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• 2010

In this study, we have investigated the effects of Cr dopant on the sintering and electrical properties of ZnO-$Sb_2O_3$ (ZS) ceramics for varistor application. Spinel phases including $\alpha-$ and $\beta$-type was formed at ZS system and $\alpha$-spinel was stabilized by Cr doping in ZS system. Densification of ZS and ZSCr system was retarded to $1000^{\circ}C$ by the formation of spinel at $800^{\circ}C$. The morphology and its distribution of spinel phases in ZS system was homogeneous but disturbed by Cr doping. In ZSCr the densification of ZnO compared with ZS system was more retarded by low concentration of Zn interstitial defects induced by Cr doping in addition to the effect of spinel phase formation. The defects in each system were identified as attractive coulombic center (ZS: 0.13 eV, ZSCr: 0.12 eV) and singly charged oxygen vacancy $V_0^{\cdot}$ (ZSCr: 0.33 eV). In all ZS and ZSCr system have week varistor behavior by the formation of double Schottky barrier at grain boundary but its stability of barrier was very sensitive to sintering temperature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.5
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• pp.411-417
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• 2020

In this study, we introduce a Na β"-alumina composite thick film as a solid electrolyte, to reduce the resistance of electrolyte for a Na/S battery. An alumina/zirconia composite material was used to enhance the mechanical properties of the electrolyte. A solid electrolyte of about 40 ㎛ thick was successfully fabricated through the conversion and tape-casting methods. In order to investigate the effect of the surface treatment process of the solid electrolyte on the battery performance, the electrolyte was polished by dry and wet processes, respectively, and then the Na/S batteries were prepared for analyzing the battery characteristics. The battery with the dry process performed much better than the battery made with the wet process. As a result, the battery manufactured by the dry process showed excellent performance. Therefore, it is confirmed that the surface treatment process of the solid electrolyte has an important effect on the battery capacity and coulombic efficiency, as well as the interface reaction.

• Journal of IKEEE
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• v.22 no.4
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• pp.999-1005
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• 2018

This paper proposed a search-based high resolution frequency estimation method in power systme. The proposed frequency estimation method adopts a slope-based adaptive search as a base of adaptive estimation structure. The architectural and operational parameters in this adaptive algorithm are changed using the information from context layer analysis of the signals including a localized full-search of spectral peak. The convergence rate of the proposed algorithm becomes much faster than those of other conventional slope-based adaptive algorithms by effectively reducing search range with the application of the localized full-search of spectrum peak. The improvements in accuracy and convergence rate of the proposed algorithm are confirmed through the performance comparison with other representative frequency estimation methods, such as, DFT(discrete Fourier transform) method, ECKF(extended complex Kalman filter), and MV(minimum variable) method.

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.83-92
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• 2019

This descriptive convergence research aimed to explore predictors of retention intention of nurses. Participants were 207 nurses from five small and medium-sized hospital located in city G and province J. Data were analyzed with descriptive statistics, independent t-test, one-way ANOVA, pearson's corelation coefficient and stepwise multiple regression. Among predictors, nursing practice environment, age, peer group caring interaction, current hospital work experience, and assignment to desired department significantly affected retention intention and nursing practice environment had the greatest effect on retention intention(${\beta}=.35$). Based on the results of this study, it is necessary to make efforts to improve nursing practice environment, caring interaction and good relationship between organizations.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.45-52
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• 2019

This study was to examine whether an middle-aged adults can depression by the mediating effect of periodontal status on the association between health practice behavior and depression. The analysis was conducted on 2,064 of the aged 45 to 64 in middle-aged by using raw data from the 2015 National Health and Nutrition Survey. The data were analyzed using SPSS for windows version 24.0 and SPSS PROCESS-macro. As a result, middle-aged depression was higher in female(0.15) than in male(0.10). The living alone were the lowest in the health practice behavior(3.92) and the highest in the depression(0.25) and the periodontal status(1.76). Also, analysis using the PROCESS macro indicated that the periodontal status has a mediating effect between health practice behavior and depression. These findings suggest that periodontal status is closely related to depression and this will be used as basic data for development of mental health promotion programs for middle-aged adults.