• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.9
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• pp.10-17
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• 1994

In this paper, a priority schedling and a flow control algorithm with hysteresis effect are proposed for high-speed networks. A mathematical model for the flow control is proposed and a cell transition probability from this model is found. And the performance of the proposed algorithm is analyzed by a computer simulation. According to the simulation results, it can be shown that the priority scheduling and the flow control with hysteresis effect get the cell loss probability 0.061 better and the average delay 100ms better and the average delay 100ms beter than those of single threshold.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.993-998
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• 1988

Adaptive control system has evolved as an attempt to avoid degradation of the dynamic performance of a control system when environmental variations occurs. While the feedback control system is oriented toward the elimination of the effect of state perturbations, the adaptive control system is oriented toward the elimination of the effect of structural perturbation, upon the performances of the control system. The model reference adaptive controller is utilized in velocity loop controller for positioning and tracking is designed based on the linear decoupled dynamics.

• Journal of Families and Better Life
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• v.25 no.4
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• pp.169-179
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• 2007

The purpose of this study was to examine the effect of mother's psychological control, children's behavioral autonomy and self control on children's behavioral problems(depression, anxiety, withdrawal, and aggression). The subjects were 293 6th graders residing in Cheonan. It was found that children's perceptions of mother's psychological control was significantly related with the level of children's depression, anxiety, withdrawal, and aggression. In addition, Children's behavioral autonomy was significantly predictor of depression and anxiety. Children's depression and aggression were influenced by self control of children. Finally the relative effect of mother's psychological control, children's behavioral autonomy and self control on problems behavior were as follows. Children's depression and anxiety were predicted by mother's psychological control. The other side withdrawal problem. was influenced by mother's psychological control on boys, by self control on girls. The children's aggression was influenced by self control in all cases.

• Journal of Advanced Information Technology and Convergence
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• v.8 no.2
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• pp.101-110
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• 2018

This paper introduces feedback linearization (FL) based adaptive sliding mode control (ASMC) effective against ground effects of the quadrotor UAV. The proposed control has the capability of estimation and effective rejection of those effects by adaptive mechanism, which resulting stable attitude and positioning of the quadrotor. As output variables of quadrotor, x-y-z position and yaw angle are chosen. Dynamic extension of the quadrotor dynamics is obtained for terms of roll and pitch control input to be appeared explicitly in x-y-z dynamics, and then linear feedback control including a ground effect is designed. A sliding mode control (SMC) is designed with a class of FL including higher derivative terms, sliding surfaces for which is designed as a class of integral type of resulting closed loop dynamics. The asymptotic stability of the overall system was assured, based on Lyapunov stability methods. It was evaluated through some simulation that attitude control capability is stable under excessive estimation error for unknown ground effect and initial attitude of roll, pitch, and yaw angle of $30^{\circ}$ in all. Effectiveness of the proposed method was shown for quadrotor system with ground effects.

• Journal of the Korean Home Economics Association
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• v.39 no.8
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• pp.37-52
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• 2001

The purpose of this study was to explore the relationships of mother's childrearing behavior, children's behavior problems, locus of control and peer victimization. The subjects were 360 children of 4th and 6th grade and their mothers. The instruments were Peer Victimization Scale, CBCL, Locus of Control Scale for Children, Childrearing Behavior Scale. The major findings of this study were as follows; (1) The type of peer victimization had a significant difference between girls and boys. That is, boys were more focused on overt victimization than girls. There was no significant gender difference in relational victimization, And there was no significant grade difference in overt and relational victimization. (2) Mother's rejection-restriction childrearing behavior, children's social withdrawal behavior problems, extemal locus of control predicted children's peer victimization. 24% of the variance of children's peer victimization was explained by these variables. (3) Mother's rejection-restriction childrearing behavior was the first contribution factor and had a direct and indirect effect through children's locus of control on children's peer victimization. And children's social withdrawal behavior problems was second contribution factor and had a direct effect on children's peer victimization. Children's locus of control had a direct and indirect effect through children's social withdrawal behavior problems on children's peer victimization. Mother's warmth-acceptance and permissiveness-nonintervention childrearing behavior had indirect effect through children's locus of control on children's peer victimization.

• Journal of Sasang Constitutional Medicine
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• v.19 no.2
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• pp.155-169
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• 2007

1. Objectives This study aimed to investigate the anti-oxidative effect of Nocyongdaebo-tang (NYD) decoction in oxidized rats induced by AAPH. 2. Methods AAPH (2.2-azobis-2 aminodinopropane-hydrochloride) was injected intraperitoneally to induce oxidization and NYD was orally administered to the rats. To observe the anti-oxidative effect of NYD, we performed blood chemistry analysis, histological analysis, and evaluated the levels of SOD, catalase, glutathione, NO and MDA in liver. 3. Results & Conclusions 1) Serum Albumin level was increased significantly in the NYD group as compared with the control group and the saline group. 2) Serum LDL-cholesterol level was reduced significantly in the NYD group as compared with the control group. 3) GPT level in liver was reduced significantly in the NYD group as compared with the control group. 4) SOD, catalase activity and glutathione levels were increased significantly in the NYD group as compared with the control group and the saline group. 5) The levels of NO and MDA were reduced significantly in the NYD group as compared with the control group. 6) The degenerative change of liver tissue of NYD group was decreased in comparison with the control group. In conclusion, NYD decoction is considered to have an anti-oxidative effect in rats.

• Journal of Distribution Science
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• v.17 no.11
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• pp.81-92
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• 2019

Purpose: The salesperson, the core of the operating activities, plays the role of connecting the inside and outside of the company, representing the company to the consumer and identifying and responding to the customer's needs. The department store industry is the most representative retail industry in South Korea, and competition among its peer group and industry is intensifying, requiring differentiated service sales activities and performance from its employees. This study divided the sales force system into activity control(process-oriented control) and output control(performance-oriented control) and verified the differential impact on the job attitude of the salesperson (e.g., job satisfaction and burn-out), respectively. In addition, the effect of job satisfaction and burn-out of the salesperson on the job performance were checked. Research design, data, and methodology: The survey was conducted on 200 sales people working at five branch stores of Hyundai department store in Seoul, and 194 of them were analyzed. The reliability and validity of the variables were analyzed and hypotheses were verified through the SEM. Results: Results have shown that activity control has a greater impact on burn-out compared to output control, and output control has a greater impact on job satisfaction compared to activity control. It has been shown that the salesperson's burn-out does not affect sales performance, but that job satisfaction has a positive effect on sales performance. Conclusions: This study examines the effect of sales force management system such as activity control and output control, on the job attitude and sales performance in department stores. According to the results of this research, each of two control systems have a discriminatory effect on the job attitude variables. For the sales managers of department store, it is recommended to increase the efficiency of sales management by increasing the use of outcome control compared to activity control.

• 한국전산유체공학회:학술대회논문집
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• 2004.10a
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• pp.115-119
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• 2004

The effect of a continuous blowing or suction on an oscillating 2-D NACA0012 airfoil was investigated numerically for the dynamic stall control. The influence of control parameter variation was also studied in the view point of aerodynamic characteristics. The result showed that the blowing control kept a higher lift drag ratio before stall angle but the dynamic stall angle was not exceed to without control result. As the slot position was closer to leading edge, the positive control effect becomes greater. The stronger jet and the smaller jet angel made more favorable roles on the control performance. In the cases of the suction, the overall control features were similar to those of the blowing, but dynamic stall angle was increased, i.e. suction was more effective to control dynamic stall. It was also founded that the suction control was showed better control effect as the slot position moves to trail edge within thirty percentage of chord length. In the simulation for the jet strength and the jet angle control, the same tendencies were observed to those of blowing cases.

• Journal of Industrial Technology
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• v.28 no.B
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• pp.167-174
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• 2008

In this paper, the analysis on type effect of inverter output voltage distortion on the control of an induction motor is discussed. The inverter output voltage is distorted differently from the reference voltage owing to the inverter nonlinear characteristic. The inverter nonlinear characteristic results from the voltage drop, the inherent characteristic of the power semiconductor, and the dead time for preventing the short circuit of the inverter leg. This characteristic distorts the inverter output voltage and then, causes the motor flux estimation error. Although this characteristics do not significantly effect in the general-purpose induction motor control, but significantly effect on the low-speed operation of high performance motor control such as the sensorless vector control.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.625-629
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• 1998

So far a single-axis controlled repulsive type magnetic bearing system have been designed and fabricated in our laboratory employing the repulsive forces operating between the stator and rotor permanent magnet for levitation. The radial axis is uncontrolled passive one. The higher speed of operation is limited due to the vibration along the uncontrolled axis and the increase of control current due to eddy current interference. This paper will discuss a detailed modeling of the repulsive type magnetic bearing system for five axis control including the eddy current effect and the method of reduction of eddy current effect. Simulation results using Matlab will be presented.