• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.103-106
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• 1996

This paper presents an iterative fuzzy learning control scheme which is applicable to a broad class of nonlinear systems. The control scheme achieves system stability and boundedness by using the linear feedback plus adaptive fuzzy controller and achieves precise tracking by using the iterative learning rules. The switching mode control unit is added to the adaptive fuzzy controller in order to compensate for the error that has been inevitably introduced from the fuzzy approximation of the nonlinear part. It also obviates any supervisory control action in the adaptive fuzzy controller which normally requires high gain signal. The learning control algorithm obviates any output derivative terms which are vulnerable to noise.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.12
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• pp.980-984
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• 2001

When robot manipulatros as mathematically modeled. uncetainties may not be avoided. The uncertain factors come from imperfect knowledge of system parameters, payload change. friction, external disturbance and etc. In this work, we proposed a class of robust hybrid control of manipulatosrs. We propose a class of expanded robust hybrid control with the separated bound function and the simulation results are provided to show the effectiveness of the algorithm.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.6
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• pp.359-365
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• 2005

This paper presents an reduced-order near-optimal controller for the congestion control of Available Bit Rate (ABR) service in Asynchronous Transfer Mode (ATM) networks. We introduce the model, of a class of ABR traffic, that can be controlled using a Explicit Rate feedback for congestion control in ATM networks. Since there are great computational complexities in the class of optimal control problem for the ABR model, the near-optimal controller via reduced-order technique is applied to this model. It is implemented by the help of weakly coupling and singular perturbation theory, and we use bilinear transformation because of its computational convenience. Since the bilinear transformation can convert discrete Riccati equation into continuous Riccati equation, the design problems of optimal congestion control can be reduced. Using weakly coupling and singular perturbation theory, the computation time of Riccati equations can be saved, moreover the real-time congestion control for ATM networks can be possible.

• The Korean Journal of Elementary Counseling
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• v.8 no.1
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• pp.95-107
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• 2009

The purpose of this study was to investigate the effect of social skill training on the class cohesiveness of Elementary School students. The experimental group received 12 times of the social skills training for 6 week period. And each training session which lasted for 40 minutes took place twice a week. A total of 59 5th grade students in randomly selected two classes of D Elementary School in N. Gyongsang participated in this study. They were divided into the two groups, again at random; an experimental group(N=30, Male=18, Female=12) and a control group(N=29, Male=15, Female=14). In this study, the class cohesiveness performance test reorganized into 20 items for the level of elementary students by Shin-suk Gang, was applied, after complemented. And, the collected data were analysed through SPSS 14.0. T-test was applied to find out the difference of the average between the experimental group and the control group and the average difference in the pre-and post-test of the experimental group alone, and to see whether the control group and the experimental group are homogeneous. The research design of this study is pre-and post-test control group design. The result of this study is as follows: The result of Independent t-test and Paried t-test on the cohesiveness score and sub-factor scores tells us that the experimental group which received the social skills training showed better achievement that deserves our attention compared to the control group. This result suggests that student's class cohesiveness(class atmosphere, mutual trust, morale, a sense of unity, communication) is positively affected by the social skill training. Accordingly, social skill training which develops class cohesiveness can be an effective strategy for elementary school students to make them more intimate and cooperative with their classmates.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.157-165
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• 2019

The purpose of this study was to verify effects of virtual reality based intervention program on communication skills in cafe and class attitudes of students with intellectual disabilities. To do this, 30 students with intellectual disabilities were participated in this study and placed an experimental group and a control group. An experimental group took part in the virtual reality based intervention program on communication skills in cafe and a control group joined in the traditional intervention program at summer vacation from July, 22 to August, 24. Intervention programs of an experimental group and an control group were conducted 5 times in a week for 4 weeks and a class time of each class was 50 minutes. Evaluations of two groups were carried out in pre-test and post-test and data of evaluation was analyzed by independent t-test. In Results of study, communication skills of experimental group were improved higher than control group's. Also, class attitudes of experimental group were changed more positive than control group's on job training class. We knew that virtual reality based intervention program was effectively utilized in transitional education for students with intellectual disabilities.

• 대한공업교육학회지
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• v.37 no.2
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• pp.147-160
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• 2012

The purpose of this study was to examine the effects on the academic achievement and learning satisfaction according to the presentation method of the multimedia materials for 'transportation technology' units of technology home economics subject. The subjects were assigned in third conditions; Text type explanation class, multimedia class and multimedia video class with narration. The data of six evaluation questions obtained from the survey of 93 high school girl were analyzed using SPSS program. The results of the study were as follows : First, in the learning satisfaction average level(M) of the students' overall responses to the questions, multimedia teaching learning class(experimental group 1) is the first(M=4.14), multimedia video class with narration(experimental group 2) is the second(M=3.16), and instructor-led class(control group) is the third (M=2.63). Therefore, the teaching learning multimedia class(experimental group 1) was most effective. Second, looking at the correlations between the students' responses to the questions, in an interesting class, the students have a retentive memory and comprehension, but a lower concentration can not a retentive memory. Third, multimedia teaching learning class(experimental group 1) has the best degree at the level of academic achievement, but instructor-led class(control group) and multimedia video class with narration(experimental group 2) have similar degree in the second place. To increase academic achievement, an instructor-led class is important to arouse interest and a multimedia video class with narration is required ways to improve level of concentration.

• Women's Health Nursing
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• v.8 no.3
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• pp.345-357
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• 2002

The purpose of this study is to find out how the Father Class, which is being practiced at a hospital located in Seoul, influences on fathers' level of knowledge and confidence of postpartal mother and newborn care. Research design was quasi-experimental study using non equivalent experiment and control group. The data, questionaires, were collected from Sep. 13, 2001 to Oct. 31, 2001 through e-mail, telephone and mail, after discharge from S hospital located in Seoul, where the experimental group was educated at the Father Class and control group didn't take part in the class. The objects were the fathers who have the first baby through normal delivery or C-sec delivery including experimental group 48 persons and control group 52 persons. Four instruments were the revised ones of Lee Mi Kyoung's(1990) and Kwak Yon Hee's tool based on the resources of direct interviews of fathers and one expert, professor. The reliability of four instruments were Cronbach's $\alpha$ scores .85 -93. Data were analyzed by SPSS 10.0 program using $x^2$-test, and t-test and, One- way ANOVA, and Pearson correlation, etc. The results of this study are as follows; 1.The two groups were confirmed as a homogeneous group by showing no significant difference statistically at the level of 5%. 2.The results of proving the hypothesis are followings: 1)The first hypothesis, "the fathers who participated in the Father Class will have the higher level of knowledge about postpartal mother care than the fathers who didn't" was accepted by significant difference statistically (p=0.000). 2)The second hypothesis, "the fathers who took part in the class will have the higher confidence in postpartal mother care than the fathers who didn't", was supported by significant difference statistically (p=0.000). 3) The third hypothesis, "the fathers who attended the class will have the better knowledge about taking care of newborn than the others", was accepted by significant difference statistically (p=0.000). 4)The fourth hypothesis, "the fathers who participated in the class will have the higher confidence in newborn care than others," was supported by significant difference statistically (p=0.000). 3.The further analysis showed whether they participated in Prenatal Birth Preparing Class influenced on the father's level of knowledge and confidence in postpartal mother and newborn care. In conclusion, the Father Class is the effective nursing intervention strategy that can help new fathers attain father and husband roles by enhancing the level of confidence in and knowledge of the postpartal mother and newborn care.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1899-1911
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• 2018

In this work, we propose a concurrency control scheme in object-oriented database (OODB). Since an OODB provides complex modeling power than the conventional relational databases, a concurrency control technique in OODB is also rather complicated and has influence on the overall performance. Thus, it is very important to develop a concurrency control technique with less overhead. The proposed scheme deals with class hierarchy that is a key concept in OODBs. The proposed scheme is developed on implicit locking scheme. Also, the proposed scheme is designed using data access frequency in order to reduce locking overhead than implicit locking. It means that, if access frequency information is not available, the proposed scheme works just like the existing implicit locking, In our work, the correctness of the proposed scheme is proved. The performance is analyzed depending on access types. Also, it is proved that our scheme performs works much better than the implicit locking does.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.444-444
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• 2000

For a class of nonlinear systems which satisfy a certain condition so called output feedback exponential passivity (OFEP), it is well known that one can easily design a high-gain output feedback control system. The designed high-gain controller has simple structure and high robustness. However, from the viewpoint of practical application, it is important to consider a robust control scheme for controlled systems for which some of the assumptions of output feedback stabilization are not valid. In this paper. we deal with a design problem of the robust high-gain adaptive output feedback control for the above-mentioned class of nonlinear systems with uncertain nonlinearities and/or disturbances.

• Structural Engineering and Mechanics
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• v.56 no.3
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• pp.385-407
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• 2015

This paper deals with the problem of the global stabilization for a class of tension leg platform (TLP) nonlinear control systems. It is well known that, in general, the global asymptotic stability of the TLP subsystems does not imply the global asymptotic stability of the composite closed-loop system. Finding system parameters for stabilizing the control system is also an issue need to be concerned. In this paper, we give additional sufficient conditions for the global stabilization of a TLP nonlinear system. In particular, we consider a class of NN based Takagi-Sugeno (TS) fuzzy TLP systems. Using the so-called parallel distributed compensation (PDC) controller, we prove that this class of systems can be globally asymptotically stable. The proper design of system parameters are found by a swarm intelligence algorithm called Evolved Bat Algorithm (EBA). An illustrative example is given to show the applicability of the main result.