• Journal of the Korean Mathematical Society
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• v.36 no.5
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• pp.833-846
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• 1999

In this paper, we will study the relationship between the controlling factor of the solution to a difference equation and the solution of the corresponding differential equation. Many times the controlling factors are the same. But even the controlling factor of the two solutions may be different, we will discover a way to compute, for first order non-linear equations, the controlling factor of the solution to the difference equation using the solution of the differential equation.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.428-430
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• 2008

Dye-sensitized solar cell has many internal resistant components such as Pt counter electrode, $TiO_2$/dye/electrolyte, charge diffusion, sheet resistance of TCO. Among these, the resistance about the counter electrode can be reduced by increasing the roughness factor of Pt counter electrode. This causes the increase of fill factor and improvement of efficiency. And the amount of light reflection on the counter electrode also increases as the roughness factor goes up. In our experiment, we suggest a new deposition structure of Pt thin film that is a stepped-type structure. The more step lines are in the counter electrode, the more roughness factor is. As a result, we get the improvement of fill factor and efficiency by controlling the roughness factor of counter electrode.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2283-2286
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• 2003

This paper presents conservation of electrical energy in building with harmonics analysis and compensation which occur in electrical system. We use load controlling and management system in order to adjust load factor of system.The maximum demand limiting and controlling are used ,then the system can acquire the prediction and compare it to the maximum demand set point.The electrical signal analysis based on FFT technique. The harmonics are compensated by using harmonic filters.This system consists computer which works as controller, processor , analysis and database unit together with digital power meter in form of multidrop network through serial communication via RS-485.The load control system uses PLC to control load via serial communication RS-485. The A/D converter is used for sampling the electrical signals via parallel port of computer.The harmonic filters are controlled by a computer.The data of measurement such as voltage, current, power, power factor, total harmonic distortion, energy, etc., can be saved as database and analysis. The load factor is adjusted by limiting and controlling maximum demand. The load factor adjustment can reduce the cost of electric consumption and energy generation together with harmonics compensation in order to increase high efficiency of electrical system.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.201-203
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• 2009

In the VANET, density is a most important factor for reception rate of packet. So, we have to find solutions to reduce packet collision. There are two approaches. First, packet collision avoid by controlling transmission interval. Second, packet collision avoid by controlling transmission power. In this paper, we propose a simple method to reduce a packet collision by controlling transmission power. It uses the number of neighbors and adaptive controlling method. This method have better performance about packet reception rate.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.999-1001
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• 1992

This paper describes the voltage type PWM converter. Input AC current is to be sinusoidal and AC input voltage is determined by controlling the phase of the source and converter properly. By corresponding the phase of input voltage to that of base current, DC constant voltage Is to be output with high power factor driving. Also it is possible to be leading or lagging power factor driving. Optimum driving is performed by controlling the current instantaneously in the steady state or transient state.

• Journal of Welding and Joining
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• v.28 no.3
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• pp.59-64
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• 2010

The purpose of this study is to identify the principal factor controlling transverse residual stress at the weldment for joining unit hull blocks. In order to do it, the comprehensive FE analyses were carried out to evaluate the effect of distance between fillet and butt weldments, stiffener span and in-plane restraint degree on the amount and distribution of transverse residual stress in way of the weldments between unit hull blocks. In accordance with FEA results, principal factor controlling the amount of transverse residual stress at the weldments was identified as in-plane restraint degree of butt weldment for unit blocks. The effect of other variables on the transverse residual stress was very small relatively.

• Journal of Families and Better Life
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• v.27 no.3
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• pp.145-158
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• 2009

The purpose of this study was to investigate the effects of socio-demographic variables, family emotional environment and maternal discipline style on school children's emotional regulation. Subjects of this study consisted 953 elementary school students drawn from 4 elementary schools in Cheong-ju city and Cheongwon-gun. Data were analyzed by the methods frequency, percentage, Cronbach's ${\alpha}$, factor analysis, Pearson's correlation, and hierarchical regression using SPSSWIN 12.0 program. The results of this study were as follows: First, girls used greater problem-focused coping than boys did. Children in sixth grade used more problem-focused coping regulation compared to those in fourth grade. When children perceived higher level of family communication, emotional support, participation of family rituals, family worries, and parental conflict, they were more likely to use problem-focused coping. Additionally, both maternal supportive discipline and behavioral controlling discipline styles increased children's problem-focused coping. Second, girls presented greater emotional venting than boys did. Children in sixth grade expressed higher level of emotional venting compared to those in fourth grade. While family communication, family worries, and parental conflict increased children's emotional venting, family emotional support and participation of family rituals decreased it. Only mothers' psychological controlling discipline positively predicted children's emotional venting. Third, girls presented higher level of children's aggressive expression than boys did. The lower level of family support increased children's aggressive expression. Higher level of family worries and parental conflict increased it as well. Also, children's aggressive expression was positively predicted by mothers' psychological controlling discipline. Fourth, girls presented greater avoidance than boys did. Children in sixth grade expressed higher level of emotional avoidance compared to those in fourth grade. In family emotional environment, while family support lowered children's emotional avoidance, family worries and parental conflict increased it. Moreover, mothers' psychological and behavioral controlling discipline styles positively explained children's emotional avoidance. In conclusion, family emotional environment was the strongest factor to predict school children's emotional regulation among other variables.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2759-2769
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• 2018

The behavioral finance view on the existence of asset pricing anomalies is based on two factors: investors' sentiment and limits to arbitrage. This paper tries to examine the effect of investors' sentiment on the stock price in the Korean stock market. In order to measure investors' sentiment, we constructed the sentiment index using principal component of five sentiment variables. By using sentiment index as an additional independent variable to three risk factors, impacts of the sentiment index on individual stocks and 25 portfolios sorted by BM-size are examined. Main results found are as follows: 1) not only all three risk factors show positive impacts on the return of individual stock, but also the sentiment index has a positive impact. SI alone explains 15% of individual return variation. 2) among four independent variables, the most important factor turned out to be the market risk factor and investors' sentiment has better explanatory power on stock price than the size effect. 3) after controlling the market risk factor, the coefficient of the sentiment index for the smallest size and highest book/market value portfolios is significantly positive. 4) all the coefficients of the sentiment index for 25 portfolios sorted by BM-size have significant positive value after controlling size or (and) value.

• Journal of Nutrition and Health
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• v.34 no.4
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• pp.393-400
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• 2001

We examined the relationship between plasma folate and total homocysteine(Hcy) levels and the distribution of plasma folate and Hcy levels from 204 Korean adults(113 men and 91 women aged between 20yr and 69yr). Plasma folate levels were significantly lower in men(12.2nmol/L) than in women(14.6nmol/L) after controlling for smoking and drinking(p<0.05). Plasma Hcy levels were significantly higher in men(13.9$\mu$mol/L) than in women(11.8$\mu$mol/L) after controlling and drinking. Plasma Hcy levels were more more strongly correlated with plasma folate in women(${\gamma}$=-0.321, p<0.05) than in men(${\gamma}$=-0.202, p<0.05), but the difference between men and women was no longer statistically significant controlling for plasma folate concentration. Prevalence of mild homocysteinemia(plama Hcy>15$\mu$mol/L) was greatest among subjects with lowest folate status. These results indicate a strong association between plasma Hcy concentration and folate status and the poor folate status is the strong causative factor of mild homocysteinemia. (Korean J Nutrition 34(4) : 393~400, 2001)

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.17-32
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• 2004

Factor analysis of data collected from 336 elementary school children provided difficuitness and susceptibility as the temperament factors, and affect and control as the nurturing factors. Results showed that non-susceptible children with low controlling mother perceived their cognitive competence positively while highly susceptible children showed no differences in their self-competence by mothers' controlling behavior. Perceived cognitive competence of susceptible boys and of susceptible 3rd graders were low when their mothers asserted low control. Thus, mothers' controlling behavior supported perceived cognitive competence in highly susceptible boys and 3rd graders. That is, the effect of mother's behavior on child's self-competence was moderated by child's characteristics. These results partially supported the Conditional Model.