• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2076-2078
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• 1998

This paper presents STATCON(Static Condenser) control schemes for voltage regulation, power factor correction and harmonics mitigation. Each control scheme can be applied in the system depending on the system requirements. The 20KVA STATCON is developed and tested in the reduced system model for the verification of three different control algorithms. The results of proposed controls are compared for power factor correction and voltage regulation algorithms. For each algorithm, harmonic mitigation scheme is adopted as a part of control. Finally verification of STATCON for the transient response is implemented by voltage flicker test.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.20-26
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• 2014

This paper presents the procedures and the results of the pitch control force via flight test for a light airplane in order to make out the stability of the aircraft and the compliance with concerned regulation. The flight test procedures were determined in order to obtain the aircraft type certification. The instrumentation equipments including airspeed indicator, accelerometer, and pitch control force measurement tools are used to perform the flight test. For the flight test, the airspeed and the pitch control force with related normal acceleration are measured sustaining turn flight with bank angle derived from trim speed. The flight test results showed that the handling qualities of the airplane are complied with the KAS-23, the regulation of the Korean government for the light airplane type certification.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.5
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• pp.71-78
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• 2012

This paper presents a digital control solution to process capacitor current feedback of high performance single-phase UPS for non-linear loads. In all UPS the goal is to maintain the desired output voltage waveform and RMS value over all unknown load conditions and transient response. The proposed UPS uses instantaneous load voltage and filter capacitor current feedback, which is based on the double regulation loop such as the outer voltage control loop and inner current control loop. The proposed DSP-based digital-controlled PWM inverter system has fast dynamic response and low total harmonic distortion (THD) for nonlinear load. The control system was implemented on a 32bit Floating-point DSP controller TMS320C32 and tested on a 5[KVA] IGBT based inverter switching at 11[Khz]. The validity of the proposed scheme is investigated through simulation and experimental results.

• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.273-280
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• 2012

Most variable speed wind turbines have pitch control mechanisms and one of their objectives is to protect turbines when the wind speed is too high. By adjusting pitch angles of wind turbine, the inlet power and the torque developed by the turbine are regulated. In this paper, the difference between the real wind speed and its rated value is regarded as a disturbance, and a component called disturbance observer (DOB) is added to the pre-designed control loop. The additional DOB based controller estimates the disturbance and generates a compensating signal to suppress the effect of disturbance on the system. As a result, the stability and the performance of the closed loop system guaranteed by an outer-loop controller (designed for a nominal system without taking into account of disturbances) are approximately recovered in the steady state. Simulation results are presented to verify the performance of the proposed control scheme.

• Proceedings of the KIEE Conference
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• summer
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• pp.60-63
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• 2004

AGC is widely used to regulate the frequency of power systems. It is also used to control the frequency of Korean Power System. Control strategies depends on systems to which it is applied. Korean Power System consists of one control area and it has no tie-line. In this research, we have developed a simulation tool to confirm AGC dynamics. The developed tool has been verified by two-machine three-bus system. Moreover an AGC control strategy has been suggested to avoid contradiction with governor dynamics. Low pass filter with relatively long time constant showed good regulation performance. This simple strategy is expected to be applied to New EMS in KPX to get reasonable AGC regulation performance.

• Korean Journal of Childcare and Education
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• v.14 no.3
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• pp.59-76
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• 2018

Objective: The purpose of this study was to examine the relationships among teachers' resilience, difficulty in emotional regulation, and teaching strategies for behavior problems of children. Methods: A total of 200 day care and kindergarten teachers were surveyed. The collected data were analyzed by Pearson's correlation and multiple regression. Results: First, teachers' resilience, difficulty in emotional regulation and teaching strategies for children with behavior problems were significantly related. Teachers' resilience showed a positive correlation with teachers' positive prevention and reaction strategies but showed a negative correlation with teachers' negative reaction strategies. Among the teachers' difficulty in emotional regulation, the factor of difficulty for impulsive control and lack of attention showed negative correlations with teachers' prevention and positive reaction strategies. Second, teachers' resilience and difficulty in emotional regulation significantly explained the teaching strategies for children with behavior problems. Teachers' resilience was found to be the most important variable explaining teaching strategies for children with behavior problems. Conclusion/Implications: This study revealed that teachers' resilience and difficulties in emotional regulation were important psychological and emotional characteristics for teachers when teaching children with behavior problems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.314-319
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• 2001

In the present study, effects of $\beta$-alanine, a known taurine antagonist for its structural similarity, on the adaptive regulation and kinetic behavior of the taurine transporter were investigated in the HT-29, human colon carcinoma cell line. Pretreatment of the cell with $\beta$-alanine(10mM) for varying periods from 3 to 30 hrs significantly reduced the taurine uptake compared to the value for control cells. This decrease in the taurine transporter activity was dependent on the incubation time with $\beta$-alanine, and the maximal down-regulation of the transporter activity was observed in cells pretreated with $\beta$-alanine for 24 hrs (25% of the control value, p<0.01). The taurine transporter appears to bind exclusively with $\beta$-alanine in the HT-29 cells since the same concentration of $\alpha$-alanine added in the culture medium for 24 hrs did not influence the taurine uptake. Kinetic analyses of the taurine transporter activity was performed in the HT-29 cell line with varying taurine concentration (5~60$\mu$M) in the uptake medium. Active taurine uptake was significantly lower in $\beta$-alanine pretreated cells compared to the value for control cells in the range of taurine concentration used in the experiment (p<0.001). The cells pretreated with $\beta$-alanine showed a 50% lower maximal velocity (Vmax, 1.7$\pm$2.0 nmole.mg $protein^{-1}$.$30min^{-1}$), and a 99% higher Michaelis constant (Km, 40.3$\pm$7.6$\mu$M) than the control values (3.3$\pm$1.9 nmole.mg $protein^{-1}$.$30min^{-1}$, and 20.3$\pm$2.1$\mu$M, respectively). These results on kinetic data suggest that $\beta$-alanine induced down-regulation of the taurine transporter activity was associated with decreases in both maximal velocity and affinity of the transporter.

• Journal of the Korean Home Economics Association
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• v.43 no.3 s.205
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• pp.59-73
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• 2005

The purpose of this study was to investigate the relationships between children's self-efficacy, parental child-rearing attitude perceived by the child, and creativity. The study subjects were 120 5th and 6th graders at elementary school in Gyeongbuk. The instruments of measurement were question sheets, Self-Efficacy Scale, and Parental child-rearing attitude Scale. For creative thinking tests, the Kim Yong-Chae version of TTCT (Torrance Test of Creative Thinking) was used. The data were analysed through mean, standard deviation, frequency, percentile, Cronbach's $\alpha$, and Pearson's Correlation Coefficient. The major findings of this study were as follows: First, the results from the correlational analysis didn't yield significant and meaningful correlations between children's self-efficacy and thinking creatively with words. Nevertheless, children's self-efficacy was partly related to thinking creatively with pictures. Second, the results from the correlational analysis didn't yield significant and meaningful correlations between warmth vs. rejection altitude of father and thinking creatively with words. Warmth vs. rejection attitudes of father was not related to thinking creatively with pictures. However, the results from the correlational analysis yielded a number of significant and meaningful correlations between self-control vs. regulation attitudes of father and the thinking creatively with words. The self-control vs. regulation attitudes of father was significantly positively related to the thinking creatively with pictures. Third, the warmth vs. rejection attitudes of mother was significantly positively related to the thinking creatively with words. However the warmth vs. rejection attitudes of mother was not related significantly to the thinking creatively with pictures. The self-control vs. regulation attitudes of mother was not related to the thinking creatively with words. Moreover, self-control vs. regulation attitudes of mother was not related to the thinking creatively with pictures.

• Journal of Navigation and Port Research
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• v.32 no.10
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• pp.785-791
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• 2008

Because of increasement on the transportation of goods by ship and the operation of coastal ships for leisure, the interest of marine parts is growing up lately and then the safe navigation of ships are essential. In these circumstances, it is necessary that it should be examined the regulation of vessel traffic control in effect. Therefore, the wave height is analyzed on korean coast, and then the seakeeping performance with the wave height and the various hull types on operating on the coast is evaluated. These results will be helpful to the improvement of the regulation of vessel traffic control and safe navigation of coastal passenger ships.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.4
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• pp.57-69
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• 2012

The purpose of this study was to identify the effect of experience emotion (i.e., happy, proud, sad, fear) on the risk perception. This study also examined interaction effects of emotion regulation (i.e., reappraisal strategy, problem focused strategy) between experience emotion and risk perception. The study collected data from 168 flight crew members in Korean commercial airlines, using an online research in which an experiment of emotion manipulation and a survey were included. The results of the study found the positive effect of happiness emotion on the risk perception regarding cases 1(these cases have high possibility of negative result and low circumstance control) and the positive effect of sadness emotion on the risk perception regarding cases 2(these cases have low possibility of negative result and high circumstance control). This study also found the interaction effect of reappraisal emotion regulation strategy between the relationship of happiness and risk perception regarding cases 2. From these results, the study provided that theoretical and practical implication that happiness and sadness emotion contribute risk perception and reappraisal strategy has a moderating role in the relationship between happy emotion and risk perception. Finally, based on these results, the limitations of this study and future research were discussed.