• 전기의세계
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• 제26권2호
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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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.

• 한국콘텐츠학회논문지
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• 제5권6호
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• pp.309-318
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• 2005

e-Learning에서 학습자는 교실에서의 면대면 학습자보다 상호협동과 책임감이 적다. 따라서 학습관리 시스템은 학습자들의 상호작용을 촉진하기 위한 협동학습 설계에 중점을 둔다. 본 논문에서는 효율적인 협동학습과 블랜디드 러닝을 지원하기 위해서 JXTA 기반의 P2P 구조를 갖는 체험학습 시스템을 제안한다. 제안 시스템은 체험학습객체 공유를 통해서 자기 주도적 학습력과 창의적인 문제 해결 능력을 개발하는데 의미가 있다. 실험결과 제안 시스템은 기존 시스템보다 학습자의 학습력 향상과 협동학습에서 더욱 효율적임을 보였다.

• 정보교육학회논문지
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• 제22권5호
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• pp.585-592
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• 2018

가상현실을 교육현장에 활용하는 소프트웨어 교육이 교사와 학생에게 높은 관심을 갖게 됨에 따라 가상현실 콘텐츠 제작 교육을 위한 연구가 이루어지고 있다. 본 연구는 학습자의 학교급별 가상현실 교육을 위해 교육대학 학생들과 초등학생, 중학생을 대상으로 가상현실 콘텐츠 제작을 교육에 따른 교육과정, 산출물, 평가결과를 비교 분석하였다. 각 집단에 대한 분석의 결과로서 특정도구에 대한 적응력은 차이가 없었으며, 산출물 제작에서 객체의 제작능력 차이를 보이고 있으며, 학습태도에서 가상현실의 제작 및 활용에 높은 자신감 및 흥미를 나타나고 있다.

• 한국CDE학회논문집
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• 제10권5호
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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.

• 한국의상디자인학회지
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• 제17권4호
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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.

• 대한가정학회지
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• 제42권9호
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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.

• 한국조리학회지
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• 제13권4호
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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.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.765-768
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• 2001

AIS(automatic identification system)는 충돌 방지를 위해 선박의 위치 정보를 전달하는 시스템으로, 핵심기법으로서 SOTDMA(seH-o.ganired time division multiple access)알고리즘을 구현해야 한다. 따라서 SOTDMA 알고리즘을 효과적으로 구현하기 위해서 성능 분석을 위한 평가 시스템의 개발이 필요하다. AIS용 SOTDMA 알고리즘 성능평가 시스템은 무선 통신 채널에 의한 선박들간의 통신 방식을 여러 선박 객체들이 공유 메모리에 독립적으로 접근하는 방식으로 모사 했다. 각각의 선박을 하나의 객체로 모사하고 무선 통신 채널을 공유메모리로 모사 했다. 여러 선박들의 보고주기와 메시지를 입력으로 주어 SOTDMA 알고리즘에 파라 각 선박들의 슬롯 할당이 이루어지며, 그 결과분석을 통해 성능분석이 가능하다. AIS용 SOTDMA 알고리즘 성능평가 시스템을 개발함으로써, AIS 개발에 사용할 프로토콜 구현시 시행 착오를 줄일 수 있으며 AIS 채널 접속 프로토콜의 충돌 횟수, Capacity와 Throughput을 예측할 수 있다.

• 사상체질의학회지
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• 제12권2호
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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.