• Journal of Society of Preventive Korean Medicine
• /
• v.7 no.2
• /
• pp.23-33
• /
• 2003

In order to study effects of Yukmiziwhang-Whan on the growth of rats, we divided the experimental rats into two groups(Control&Sample groups) and peformed the experimental study. Sample group was administered the extract of Yukmiziwhang-Whan 1.6ml/100g for 4 weeks, and Control group was administered equal dose of normal saline. We measured the body weight, the length of femur and tibia, the level of serum growth hormone, T3, T4, Insulin and testosterone. The results are summarized as follows : 1) The body weight was not changed compared with Control group. 2) The lengths of femur and tibia in the Sample group was longer than that of Control group, but it was not statistically significant. 3) The level of serum growth hormone in the Sample group significantly increased compared with Control group(p<0.05). 4) The level of serum T3 in the Sample group significantly increased compared with Control group(p<0.05) and T4 level was trending toward increasing compared with Control group. 5) The level of serum insulin in the Sample group was trending toward increase compared with Control group. 6) The level of serum testosterone in the Sample group was trending toward decrease compared with Control group. According to the above experimental results, ${\ulcorner}Yukmiziwhang-Whan{\lrcorner}$ are assumed to have effective activity on the growth of rats.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.7 no.2
• /
• pp.29-34
• /
• 1978

It was conducted to find out that the influence of lipids on blood cholesterol level of chicks and ducks. In this experiments, a comparative study was carried out using chicks and ducks divided into four groups with various diet for the period of four weeks. The results were as follows: 1. The mean value of hematocrit was significantly lower for the chicks fed sesame oil and soybean oil than the chicks fed duck meat. The value of hematocrit was higher for the ducks fed sesame oil, soybean oil and duck meat than for the control group. 2. Blood glucose level was higher for the ducks group than the chicks group. It was lower blood glucose level for the chicks and ducks fed duck meat than any other groups. 3. Blood cholesterol level was lower for the chicks fed sesame oil, soybean oil, and duck meat than for those fed the basal diet(control group). In the ducks group, blood cholesterol level was high. But in the liver organ, it was lower blood cholesterol level for the chicks and ducks fed sesame oil, soybean oil and duck meat, respectively than for those fed the basal diet(control group). 4. Phospholipid of the chicks which were control groups was lower value than for those fed sesame oil and duck meat fed, the value of phospholipid was higher value.

• Korean Journal of Childcare and Education
• /
• v.16 no.1
• /
• pp.75-98
• /
• 2020

Objective: This study aimed to examine the influences of household chaos on self-control of young children and to investigate whether teachers' limit-setting styles had moderating effects. Methods: The participants were 184 children (83 boys and 101 girls), at age 3 -5, their mothers and teachers working at daycare centers located in Seoul and Gyeonggi-do. The data were analyzed by descriptive statistics, Pearson's correlation, and hierarchical regression. Moderating effects were examined using the Mplus8.0 program. Results: The results indicated that household chaos as well as teacher's permissive and logical limit-setting styles had significant effects on self-control of preschoolers. The lower the level of household chaos was, the higher the level of self-control of preschoolers was. The level of self-control was more likely to be high when teachers used logical limit-setting with detailed explanation to children whereas it was lower when they used more permissive limit-setting. In addition, teachers' logical limit-setting moderated the relation between household chaos and self-control of preschoolers. That is, the effects of household chaos on preschoolers' self-control were mitigated when the level of logical limit-setting was high compared to when it was low. Conclusion/Implications: The results suggested that both household chaos and teachers' limit-setting styles play important roles in increasing self-control of preschoolers.

• Korean Journal of Child Studies
• /
• v.37 no.3
• /
• pp.39-51
• /
• 2016

Objective: The present study examined the effects of school violence victimization and self-control on cyberbullying perpetration in middle school students and investigated whether self-control moderated the relationship between school violence victimization and cyberbullying perpetration. Methods: The participants of this study were 315 middle school students (172 boys; 143 girls) from three middle schools in Seoul and Incheon. To measure the level of cyberbullying perpetration, the Bullying/Victimization Questionnaire was used. School violence victimization and self-control were measured via the School Violence Victimization Scale and the Self-Control Scale, respectively. The data were analyzed by means of descriptive statistics and hierarchical regressions. Results and Conclusion: The results indicated that school bullying victimization level increased cyberbullying perpetration level whereas self-control level decreased cyberbullying perpetration. In addition, self-control moderated the effect of school violence victimization on cyberbullying perpetration. That is, the influence of school bullying victimization on cyberbullying perpetration was greater when self-control was low, compared to when it was high.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.2
• /
• pp.311-318
• /
• 2016

This paper is a study on the neutral point voltage balancing of the three-phase 3-level T-type inverter using the predictive control techniques. Recently, multi-level inverter has been attracting attention as the advantages such as efficiency improving and harmonic reduction. Especially, the T-type inverter topology is advantageous in low DC-link voltage. However, in case of the prediction control, it takes a lot of time, because there exist 27 voltage vectors and it has to be calculated according to the respective voltage vectors. Therefore, in this paper, we propose a method to implement predictive control techniques while reducing the operation time. In order to reduce the operation time, the predictive control is implemented by using the minimum voltage vector except for the unnecessary voltage vector. The result of the implemented predictive control is added to the SPWM by using the offset voltage. It was verified through simulation and experimental results.

• Journal of Advanced Marine Engineering and Technology
• /
• v.24 no.1
• /
• pp.104-111
• /
• 2000

It is very difficult to maintain the desired tank level without any overflow or any shortage in a dangerous shemical plant and in a cooling one. Futhermore, because its dynamics are very complicate and nonlinear, it is impossible to realize the precise control using the accurate mathematical model which can be applied to the various peration modes. Nonetheless, the sliding mode controller(SMC) is known as having the robust variable structures for the nonlinear control system with the parametric perturbations and with the rapid disturbances. But the adaptive tuning algorithms for their parameters are not satisfactory. Therefore, in this paper, a Real Variable Elitist Genetic Algorithm based Sliding Mode Controller (RVEGA SMC) for the precise control of the coupled tank level was tried. The SMC's switching parameters were optimized easily and rapidly by RVEGA. The simulation results showed that the tank level could be satisfactorily controlled without and overshoot and any steady-state error by the proposed RVEGA SMC.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.2
• /
• pp.209-215
• /
• 2018

This paper present a 7-level PWM inverter adopting voltage balancing control to series-connected input capacitors. The prior proposed 7-level PWM inverter consists of dc input source, three series-connected capacitors, two bidirectional switch modules, and an H-bridge. This circuit topology is useful to increase the number of output voltage levels, however it fails to generate 7-level in output voltage without consideration for voltage balancing among series-connected capacitors. Capacitor voltage imbalance is caused on the different period between charging and discharging of capacitor. To solve this problem, we uses the amplitude modulation of carrier wave, which is used to produce the center output voltage level. To verify the validity of the proposed control method, we carried out computer-aided simulation and experiments using a prototype.

• Nuclear Engineering and Technology
• /
• v.36 no.1
• /
• pp.73-82
• /
• 2004

The deaerator of a power plant is one of feedwater heaters in the secondary system, and it is located above the feedwater pumps. The feedwater pumps take the water from the deaerator storage tank, and the net positive suction head(NSPH) should always be ensured. To secure the sufficient NPSH, the deaerator tank is equipped with the level control system of which level sensors are critical items. And it is necessary to ascertain the sensor state on-line. For this, a model-based fault detection and diagnosis(FDD) is introduced in this study. The dynamic control model is formulated from the relation of input-output flow rates and liquid-level of the deaerator storage tank. Then an adaptive state estimator is designed for the fault detection and diagnosis of sensors. The performance and effectiveness of the proposed FDD scheme are evaluated by applying the operation data of Yonggwang Units 3 & 4.

• Nutritional Sciences
• /
• v.6 no.4
• /
• pp.201-208
• /
• 2003

This research was conducted to study the effects of the supplementation of multi-extracts of mori folium (MF) and of exercise on plasma insulin and glucose levels in streptozotocin (STZ)-induced diabetic rats. Eight male Sprague-Dawley rats, 4 weeks old, were assigned to each experimental group and were raised in the laboratory for 10 weeks. The animal groups consisted of a normal-control group, a STZ-control group, 3 STZ-induced diabetic groups supplemented ad libitum with various amounts of MF extracts (MF-720, MF-360, and MF-180 groups), and a STZ-induced diabetic group supplemented with MF-360 along with exercise. In the normal-control group, glucose tolerance tests resulted in the peak blood glucose level being achieved in 15 minutes and a fasting blood glucose level being achieved in 60 minutes. In the STZ-control group, the peak blood glucose level was reached after 60 minutes and, even after 90 minutes, blood glucose shown at a significantly higher level compared to the fasting levels. In the groups supplemented with MF extracts, the blood glucose level peaked after 30 minutes of glucose challenge, and returned to the fasting level after 90 minutes; the MF-360 and MF-360+exercise groups showed the best levels of glucose tolerance. Blood glucose levels in the STZ-induced diabetic groups were significantly higher compared to the normal-control group. However, after 7 weeks of supplementation with MF extracts, a significant lowering of blood glucose levels was observed in all groups supplemented with the MF extract. The best effect was observed in the group given MF extract combined with exercise. Compared to the normal-control group, blood insulin levels were significantly lower in all STZ-induced diabetic groups; however, a significantly higher level of insulin was observed in the groups given MF extracts compared to the STZ-control group. This study shows that the supplementation of MF extracts in STZ-induced diabetic rats resulted in increased blood insulin levels and lower blood glucose levels.

• Korean Business Review
• /
• v.18 no.2
• /
• pp.45-60
• /
• 2005

CSA(Control Self Assessment) is a new internal control technique whose objective is to control the human resource performance, the manager's philosophy, the business ethics, the effective communication and decision making etc. The purpose of this study is to find out if the CSA improve the quality of internal control. With the questionnaire method the following conclusions are reached. 1) Level of the management supports influence the level of the workshop participation. 2) Anonymity during the workshop session influences the level of workshop participation. 3) Level of the organizational committment influences the level of the participation 4) The level of workshop performance significantly influences the level of internal contro improvement.