• 전기의세계
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• v.26 no.2
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• pp.99-103
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• 1977

The object of this work is to study an optimal design problem of the proportional load-frequency controller for the single-control area power system. The selfservice power station is still a popular means as a power supplying source on ships or in a certain manufacturing area. The power system of this kind can be formulated as a single control-area system and it attracts a certain academic interest in controlling the system frequency under disturbances. In this paper, the single control-area system is mathematically formulated as a linear, time-invariant system in state-space under certain assumptions. The optimal proportional control law and the realization of the controller in closed loop-version is studied so that the final system designed can attain the system frequency to the nominal stationing value after the small load-disturbance. As in general cases of optimal design problems, the performance index is assumed to be quadratic in states and the control effort, and the infinite time control process is assumed in this work. The final control system realized depicts certain improvements in case study; in stability, transient responses and in steady-state frequency deviation, even though the steady state error did not attain the zero value.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.740-743
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• 1998

This paper presents an optimization algorithm for a stable Dynamic Neural Network (DNN) using genetic algorithm. Optimized DNN is applied to a problem of controlling nonlinear dynamical systems. DNN is dynamic mapping and is better suited for dynamical systems than static forward neural network. The real time implementation is very important, and thus the neuro controller also needs to be designed such that it converges with a relatively small number of training cycles. SDNN has considerably fewer weights than DNN. The object of proposed algorithm is to the number of self dynamic neuron node and the gradient of activation functions are simultaneously optimized by genetic algorithms. To guarantee convergence, an analytic method based on the Lyapunov function is used to find a stable learning for the SDNN. The ability and effectiveness of identifying and controlling, a nonlinear dynamic system using the proposed optimized SDNN considering stability' is demonstrated by case studies.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.309-318
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• 2005

Learners show lower cooperation and responsibility at e-Learning(Electronic Learning) than face-to-face learners in class. Accordingly the LMS(Learning Management System) focus on collaborative learning design in order to promote the learner's interaction. In this paper, the Experience Learning Support System with JXTA-based P2P(Peer-to-Peer) architecture is proposed for an effective collaborative learning and a blended learning. It intends learners to develop a self-leading learning ability and a creative problem-solving ability through experience learning object's sharing. The experimental results described that the proposed system was more effective in an enhancing learner's learning ability and a cooperative learning than existing system.

• Journal of The Korean Association of Information Education
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• v.22 no.5
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• pp.585-592
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• 2018

As the software education which utilizes the virtual reality in the education field becomes more interested in the teachers and the students, researches are being conducted for the education of virtual reality contents production. The purpose of this study is to analyze the curriculum, outcomes, and evaluation results of virtual reality contents production for educational students, elementary school students, and middle school students. As a result of analysis on each group, there was no difference in adaptability to specific tools, differences in ability of object production in production, and self-confidence and interest in production and utilization of virtual reality in learning attitude.

• Korean Journal of Computational Design and Engineering
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• v.10 no.5
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• pp.375-379
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• 2005

Durability of rubber dust cover in the ball joint for automotive suspension parts is analyzed by FEM and compared with experimental data. Upper open area of ball joint is sealed by dust cover for preventing outflow of the lubricating oil and intrusion of send, dust, water, etc. This rubber cover undergoes repeated loadings such as tension and compression while the car is running. Analysis about rubber material needs to consider every kinds of nonlinearities arise in finite element analysis, which are geometric nonlinearity due to large displacement and small strain, materially nonlinearity and nonlinear boundary condition such as contact. The deformation behavior of dust cover is analysed by using the commercial finite element program MARC. In the study, this program could solve these kinds of nonlinear analysis accurately. Finite element model of dust cover is considered as 3-dimensional half model based on 2-dimensional axisymmetric model. Material property of rubber is modeled by Ogden model and input data for calculation takes form uniaxial tension test of rubber specimen. The final object of the study is obtaining the design specification of dust covers and the result of analysis should be a useful data to design of rubber cover.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.4
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• pp.131-144
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• 2015

The object of this study was to find out the influence of female consumers' cosmetics purchase experience on image-making efficacy and cosmetics pursuit benefits. Total 405 surveys of women working at the industrial complex in Daegu-Kyoungbuk area were used for data analysis. Frequency, factor analysis, reliability analysis, regression analysis, and ${\chi}^2$-test were used for data analysis. Our findings are as follows. Cosmetics purchase experience of female consumers had factors as recognition experience, relationship experience, emotional experience, visit experience, and sensual experience. The factors of image-making efficacy were self-confidence in displaying, ability of facial expression and display ability while those of cosmetics purchase experience turned out to be trend/brand pursuit, appearance improvement pursuit, functionality pursuit and economic feasibility pursuit. Cosmetics purchase experience was found to have significant effects on the factors of image-making efficacy, and cosmetics purchase experience on factors of cosmetics pursuit benefits. The differences by ages variable was examined with relation to the level of make-up and how they chose products when buying.

• Journal of the Korean Home Economics Association
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• v.42 no.9
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• pp.213-235
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• 2004

This study investigated the Infant Institutional Household (IIH) for the care of infants. The purpose was to provide basic information needed to raise Korea's birth rate and to design higher level nursing facilities which can satisfy working mothers who are presently offered few facilities. To achieve this purpose. IIM was divided into 7 sub-functional stations : planning-management, marketing, materials-management, business-management, man power-management, financial-management and control etc. The results are as follows : 1. Kind of facilities : Infants'(full responsibility) Institutional Household. 2. Number of infants : total 19 babies. 3. Ratio of infants to teachers : one to one (Contained assistance teachers) 4. Installing region : convenient traffic place - in Seoul. 5. Building site and kind : the first floor space of 60pyung (198㎡) in the Apartment complex which . contained many apartments of small size. 6. Nursing time : 24-hour day care in weekdays Age of object : age from 1month to 24months old babies(after his/her birth). 7. Kind of services and Cost : mother-like care, cost includes nursing-fee, a deposit and admission-fee. 8. Economic Condition and managing direction : pursuit limited profits with nursing-fee, admission-fee, a loan and national (or self -government of direct) supplementary funds.

• Culinary science and hospitality research
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• v.13 no.4
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• pp.186-198
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• 2007

Recently, the desire of the students has been changing variously as time passes and its speed is being accelerated. In this respect, this paper aims to demonstrate college students' menu choice behavior. In order to attain the object of this paper, college students in Chung-Nam Province including Daejeon city have been studied. There are many kinds of manu choice factors in food-industry. One of the methods of this study is Khan's food choice factor. The results of this analysis suggest that hypothesis 1-1, the environmental factors for college students were verified as significant effects on menu choice behavior of other people and also hypothesis $1{\sim}2$, self oriented for menu choice behavior showed significant effects. As a result, Khan's food choice behavior should be comparative to each factor focused on diversified environments. And also each factor is not strongly affected in relation to food choice factor. Therefore, students' menu choice behavior will be measured by verifying factors.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.765-768
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• 2001

A universal shipborne automatic identification system(AIS) uses self-organised time division multiple access(SOTDMA). The performance evaluation system of the SOTDMA algorithm for AIS is needed to implement it efficiently. This paper shows the method of designing it. Real ships access the VHF maritime mobile band but in this performance system, several ship objects access the shared memory. Real ships are designed as the object and the wireless communication channel is designed as the shared memory. This system shows several stations are assigned the transmission slot by the SOTDMA algorithm

• Journal of Sasang Constitutional Medicine
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• v.12 no.2
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• pp.1-7
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• 2000

Greeting the 100 year celebration of the death of Master Dong-mu, through investigating his thoght on Scholarship and Philosophy, and his new view of human being based on Sasang, I tried to reevaluate him as a Confucianist of practical mind. The conclusions were as followings ; 1. Dong-mu's recognition system of things is that based on the mind of summarizing things in view of Affair-Mind-Body-Object originated from Confucianism, and It developed 'the Marvel of Easiness & simpleness based on Yin-yang' into 'the Marvel of Easiness & simpleness based on Sasang' 2 Through understanding old Confucianism newly, Dong-mu summarized human being as having a natural character in view of Nature and Order and an autonomical character in view of Knowledge and Deed, and emphasized an autonomical character in view of Knowledge and Deed 3. In view of Knowledge and Deed, Dong-mu presented How to Say and Behave, and took it as a model of behavior in the new Confucianism. Also he presented the view of Knowledge and Deed based on Constitutions, and took it as a new mind of treatment. 4. Dong-mu can be estimated highly, in that he completed a new confucian view-point of Human being in the period of philosophic chaos, and executed the mind of General health maintenance and the mind of control others through a confucian self-control.