• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.8
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• pp.71-77
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• 1992

According to increasing the doping concentration in p-n junction, a tunneling current through trap as well as SRH(Shockley-Read-Hall) generation-recombination current in depletion region occurs. It is the tunneling current that is a dominant current at the forward bias. In this paper, the new tunneling-recombination equation is derived. The thermal generation-recombination current and tunneling current though trap can be easily calculated at the same time because this equation has the same form as the SRH generation-recombination equation. For the validity of this equation, 2 kind of samples are simulated. The one is $n^{+}$-p junction device fabricated with MCT(Mercury Cadmium Telluride, mole fraction=0.29), the other Si n$^{+}-p^{+}$ junction. From the results for MCT $n^{+}$-p junction device and comparing the simulated and expermental I-V characteristics for Si n$^{+}-p^{+}$ junction, it is shown that this equation is a good description for tunneling through trap and thermal generation-recombination current calculation.

• Journal of Hydrogen and New Energy
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• v.17 no.4
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• pp.448-453
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• 2006

Porous Co-P catalysts electroplated on Cu in chloride based solution with an addition of $NaH_2PO_2$ and glycine were developed for hydrogen generation from alkaline $NaBH_4$ solution. The microstructures of the Co-P catalysts and their hydrogen generation properties were analyzed as a function of cathodic current density and plating time during the electrodeposition. Amorphous Co-P electrodeposits with porous structure was formed on Cu at cathodic current density of $0.05\;A/cm^2$, and showed very high hydrogen generation rate in alkaline $NaBH_4$ solution due to an increase in the surface area of the catalyst as well as the catalytic activity. The Co-P catalyst, which was obtained at cathodic current density of $0.05\;A/cm^2$ for 5 min, exhibited the best hydrogen generation rate of 2290 ml/min.g-catalyst in 1 wt. % NaOH+10 wt. % $NaBH_4$ solution at $30^{\circ}C$.

• Journal of the Korea Society of Computer and Information
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• v.17 no.11
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• pp.189-196
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• 2012

This paper proposes Swap algorithm for solving Dynamic Economic Dispatch (DED) problem. The proposed algorithm initially balances total load demand $P_d$ with total generation ${\Sigma}P_i$ by deactivating a generator with the highest unit generation cost $C_i^{max}/P_i^{max}$. It then swaps generation level $P_i=P_i{\pm}{\Delta}$, (${\Delta}$=1.0, 0.1, 0.01, 0.001) for $P_i=P_i-{\Delta}$, $P_j=P_j+{\Delta}$ provided that $_{max}[F(P_i)-F(P_i-{\Delta})]$ > $_{min}[F(P_j+{\Delta})-F(P_j)]$, $i{\neq}j$. This new algorithm is applied and tested to the experimental data of Dynamic Economic Dispatch problem, demonstrating a considerable reduction in the prevalent heuristic algorithm's optimal generation cost and in the maximization of economic profit.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.332-336
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• 1998

The effect of ripening temperature, pH and salinity on the formation of Nnitrosamine (NA) during Kimchi fermentation and in vitro was studied, respectively. During Kimchi fermentation for six weeks at cold storage temperature ($4^{\circ}C$) and room temperature ($16{\pm}2^{\circ}C$), the contents of nitrite and dimethylamine (DMA) showed variation at room temperature but no variation at cold storage temperature. The maximum generation of nitrosodimethylamine (NDMA) resulted low content ($2.69\;\mu\textrm{g}/kg$) at cold storage temperature but started to increase after one week fermentation and reached to the 18-fold higher generation ($49.6\;\mu\textrm{g}/kg$) at room temperature. During Kimchi fermentation, no correlation was observed between the variation of nitrite and DMA content and the generation of NDMA. However, pH showed effective relation to NDMA generation such as the highest NDMA generation was obtained at lowest pH 4. During in vitro test, higher temperature and lower pH resulted more NDMA generation and generation amount was affected more by pH. Also, the salinity of Kimchi provided inhibitory effects on the formation of NDMA. NDMA was produced $5.86\;\mu\textrm{g}/kg$ at normal salinity (2.5%) but $90.9\;\mu\textrm{g}/kg$ at lower salinity (15%) after three week. The higher salinity showed lower formation of NDMA in vitro test, too.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.3
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• pp.199-206
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• 2017

Maximum Power Point Tracking (MPPT) control needs to generate the maximum power of a tidal current turbine. A tidal current speed sensor is required to achieve effective generated power in a tidal current generation system. The most common methods used to achieve such power is the tip speed ratio of turbine and tidal current information. However, these methods have disadvantages, such as expensive installation of the tidal current sensor, parameter errors in turbine design, and different information according to the installed position of the tidal current sensor. This paper proposes a maximum power control scheme using perturb-and-observe (P&O) for tidal current generation system. The proposed P&O MPPT scheme can achieve the maximum power without tidal current sensors and turbine design parameters. The reliability and suitability of the proposed control scheme are proven through simulation and experiment results at the tidal current generation laboratory.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.19-29
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• 2017

The purpose of this study was to identify the multidimensional factors that affect the satisfaction of life by type of baby boomer generation. The subjects of this study were 1,895 households who were born from 1955 to 1963 among the respondents in the Korea welfare panel (the 10th year). The baby boomer generation was classified into four types such as gender, income status, male and female as socioeconomic status. The male type IV (B=.074, t=1.992, p<.05), health status (B=.233, t=7.268, p<.001), household income (B=.174, t=4.476, p<.001), depression (B=-.182, t=-5.242, p<.001), self-esteem (B=.255, t=7.027, p<.001), trust (B=.064, t=2.036, p<.05), etc. were found to have a significant effect on the life satisfaction of the male baby boomer generation. The female type IV (B=.100, t=2.598, p<.05), health status (B=.239, t=6.790, p<.001) (P<.001), depression (B=-.181, t=-5.142, p<.001), and self-esteem (B=.320, t=8.600, p<.001), etc. were found to have a significant effect on the life satisfaction of the female baby boomer generation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.7
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• pp.52-58
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• 2012

In this study, we have investigated the effect of the solar power generation facilities on the power quality of interconnected solar power generation system. When the solar power generation facility was connected to the distribution system, whether the solar power generation is under operation or not, Peak factor of current was increased to 0.033[%], Frequency is deviated from $60{\pm}0.2$[Hz] and also Short term flicker indication($P_{st}$) increased to 0.213[p.u.] compare with the disconnected situation. Harmonic current [%] in orders was 11.42[%] maximum under 11th orders and was 7.861[%] between 11th and 17th orders. These values were about 3 or 4 times compared with "the power system interconnection technique standards" at the same situation above. Therefore, we could confirmed that the solar power generation facility, when it was connected to the existing distribution system, made bad influence on the power qualities such as the peak factor of current, frequency regulation, short term flicker indication($P_{st}$) and harmonic current [%] in orders etc.

• Research in Community and Public Health Nursing
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• v.24 no.4
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• pp.461-470
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• 2013

Purpose: This study examined factors influencing subjective quality of life in baby boom generation men. Methods: This was a descriptive survey study. Data were collected from 279 baby boom generation men from September to October 2012. The instruments used included a subjective quality of lifescale, a self-esteem scale, a spiritual well-being scale, a communication with spouse scale, a social support scale, and a job satisfaction scale. Data were analyzed using descriptive statistics, t-test, one-way ANOVA and Scheff$\acute{e}$ test, Pearson's correlation coefficients, and Hierarchical multiple regression. Results: All variables were positively correlated with subjective quality of life. As a result, factors influencing subjective life of quality were self-esteem (${\beta}$=.21, p<.000), social support (${\beta}$=.20, p<.002), job satisfaction (${\beta}$=.19, p<.001), communication with spouse (${\beta}$=.15, p<.004), spiritual well-being( ${\beta}$=.16, p<.004), and family income (${\beta}$=.15. p<.023). These factors accounted for 61% of the total variances. Conclusion: The findings indicate a need to develop nursing intervention programs for community health nurses in consideration of these variables to improve the subjective quality of life for baby boom generation men.

• Journal of Industrial Convergence
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• v.21 no.2
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• pp.61-71
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• 2023

This is a descriptive research study to explore factors related to the perception of digital sex crimes among university students of the MZ generation in Korea. Data were collected by conducting a survey of 150 university students in Korea. As a result, the variable that showed the highest relevance to the recognition of digital sex crimes among MZ generation university students was sexual perception (β=-0.390, p<.001). Total explanatory power was 25.2% after adding gender (β=0.207, p=.018) and sexual attitude (β=0.157, p=.045). Our results suggest that customized education in consideration of factors related to digital sex crime perception is needed to form and improve a correct perception of digital sex crimes among MZ generation university students.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.193-200
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• 2017

The purpose of this study is to confirm whether spontaneous adipocyte generation during chondrogenic induction culture affects the chondrogenic differentiation of porcine skin-derived stem cells (pSSCs). For this purpose, chondrogenic differentiation characteristics and specific marker gene expression were analyzed using cell lines showing different characteristics of spontaneous adipocyte formation. Of the four different lines of pSSCs, the pSSCs-IV line showed higher Oil red O (ORO) and glycosaminoglycan (GAG) extraction levels. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that the levels of adipogenic markers peroxisome proliferator-activated receptor gamma 2 ($PPAR{\gamma}2$) and adipocyte Protein 2 (aP2) mRNAs were significantly higher in pSSCs-IV than those of the other pSSC lines (P<0.05). Among three chondrogenic markers, collagen type II (Col II) and sex determining region Y-box (Sox9) mRNAs were strongly expressed in pSSCs-IV (P<0.05), but not in aggrecan (Agg), which was significantly higher in pSSCs-II (P<0.05). These results demonstrate that the spontaneous adipocyte generation during chondrogenic differentiation has a positive effect on the chondrogenesis of pSSCs. More research is needed on the correlation between adipocyte generation and cartilage formation.