• Journal of Korean Elementary Science Education
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• v.22 no.1
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• pp.109-120
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• 2003

The purpose of this study is to observe, to analyze of the preservice teachers' naive theories about the change of season. And it is to find a instruction strategy which can solve problem about this. The general idea about the change of season is observed by the 3 methods which are simply explaining with words, explaining with pictures and models. The author is to find the similarity. difference and relationship which the preservice teachers have about the general idea about the change of season. The important changable primary factors, which can effect to the general Idea formation, are naturally dragged out through the observation of preservice teachers participation. For this study, 4 first year preservice teachers of one of national university of education are used. Before the interview. the author tries to form rapport with the preservice teachers. Experiment materials, pencil. paper, camcorder, digital recorder and interview note were used for the study with reflection of them just way they are. As the result of the interview. all of 4 preservice teachers had not being understand the concept about the change of season and the three ways of explanation methods were not matched each other, so it is revealed that the general Idea of the change of season, which the preservice teachers have, is not strongly formed. In spite of the repeated study of the change of season from elementary school to university, it has many problem about recognition of the general idea about the change of season which pre-elementary teachers have. Therefore it is needed to improve the experiment in elementary science text book and naive theories by the activity which is explaining the change of season in three dimension space. to prevent the naive theories which the preservice teachers may have.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.282-284
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• 2006

Generally PI controller is used to control the speed of an induction motor. It has the good performance of speed control in case of adjusting the control parameters. But it occurred the problem to change the control parameters in the change of operation condition. In order to solve this problem, Fuzzy control or Artificial neural network is introduced in the speed control of an induction motor. However, Fuzzy control have the problems as the difficulties to change the membership function and fuzzy rule and the remaining error. Also Neural network has the problem as the difficulties to analyze the behavior of inner part. Therefore, the study on the combination of two controller is proceeded. In this paper, Speed controller of an induction motor based fuzzy-neural network is proposed and the speed control of an induction motor is performed using the proposed controller. Through the experiment, the fast response and good stability of the proposed speed controller is proved.

• Journal of Educational Research in Mathematics
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• v.8 no.2
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• pp.663-677
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• 1998

The development of Science and Technology and the social change require new paradigm in Education. In a traditional paradigm, learners have been regarded as a passive being and knowledge could be transmitted to learner. But within this paradigm, it is difficult to confront the social change and to develop problem solving skills in various context. This results in a new, alternative perspective, Constructive paradigm. As an alternative to the traditional settings, Constructive paradigm emphasizes the learner centered instruction. The reform movement in mathematics education including NCTM's standards revolves around this paradigm and the open education movement in our educational system is based on it. Open education values learner's interest, autonomy and internal motivation in learning. However, open education has been misunderstood by most of the teachers. It should be understood as the change of paradigm. In this study, as a way of helping students connect mathematics to their everyday lives and construct meaningful mathematical knowledge and concept, mathematical modelling is suggested. It consists of posing and specifying the real problem, formulation and constructing a mathematical model, analyzing and solving a mathematical problem. interpreting the solution and comparing with reality and communicating results. In this process, technology like computer can be a powerful tool. It can help students explore various problems more easily and concretely.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.4
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• pp.171-176
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• 2021

This paper deals with bid evaluation problem that chooses the vendors and quantity with minimum purchasing cost for bid information of setup cost and unit price. For this problem, the branch-and-bound(BB) and branch-and-cut(BC) methods are well-known. But these methods can be fail to obtain the optimal solution. This paper gets the initial feasible solution with procuring quantity assignment principle in accordance with the unit price or setup cost rank-first. Then procuring quantity moving optimization(vendor change) is execute take account of unit price or setup cost rank. As a result of experimentation, the propose algorithm is significantly lower compared to BB and BC.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1167-1172
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• 2007

Generally inpipe robot needs force above standing for contacting robot to pipe. If the environment of the pipe-inside does not change, there is not a problem. But if the pipe radius change, or occur the obstacle which it does not intend, problem gets. So it uses a different system and must know an environment change, and changing the shape or a form of the robot. The research uses the flexible leg and is the robot which is adapted to the environment change of the pipe. The advantage of this robot is possible to move when it does not need to recognize a change of environment of pipe. Leg is bend with one direction. When it moves part that there are legs effect of leg direction the robot is moved with only one direction. If friction between legs and pipe is sufficient, not only verticality pipe moving, but also curved pipe moving. Also the obstacle of the pipe inside occurs and the diameter of the pipe inside changes, this robot can move if it does not use another system or device.

• Journal of the Korean Home Economics Association
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• v.31 no.4
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• pp.115-132
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• 1993

This study was designed with the purpose to analyze the factor structure of family life events and to clear the influence of related variables on family life events. The frequence of experienced events and the degree of importance of events which were the constituent components of family life events was estimated by the 650 married woman in Kangju. The results were as follows: 1. 15 factors of family life events derived by factor analysis: F.1「Expenditure and economic loss」, F.2「Growth and change of children」, F.3「Change of family structure」, F.4「Family's change」, F.5「Change of life level」, F.6「Family's social problem」, F.7「Need of care」, F.8「Family's health」, F.9「Marital relationship」, F.10「Family's social damage」, F.11「Breach with acquaintance」, F.12「Financial difficulties」F.13「Husband's problem」, F.14「Housewives' social activity」, F.15「Kinship's support」. 2. There frequence of experienced family life events such as expenditure and economic loss and breach with acquaintance was highest. 3. The degree of importance about experienced family life events such as growth and change of children was highest. 4. Age, family life cycle have significantly differenced on the degree of importance and the frequence of experienced events. 5. Education's level, family size, income, housewives' employment and family structure have differently differenced on the degree of importance and the frequence of experienced events according event factor.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.683-693
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• 2021

Shipping has become an important sector in supporting social, economic, government, defense, security, cultural and other sectors to unite separate islands and broad seas. Thus, ports automatically become an important facility in Indonesia. The purpose of this research is to test and explain the effect of Organizational readiness for change, Service Innovation, and Corporate Image on Perceived opportunity and challenge. The research model with inferential analysis uses Structural Equation Modeling (SEM) analysis with the WarpPLS approach, expected to answer the statements of problem and be able to test the desired hypothesis. The model development in this research was based on the background, statements of problem, conceptual framework and research hypotheses. The model referred to is "Complete and Comprehensive Port." Its development was carried out through studying and synthesizing various sources. The most important source is the results of literature review in the form of theoretical developments and research results, then continued with compilation. The use of Organizational Change Readiness, Service Innovation, and Corporate Image in improving Port Competitiveness is seen as one of the novelties of this research, specifically the use of the Organizational Change Readiness variable which is often used in high-flexibility companies but now used in port companies as well.

• Journal of Information Processing Systems
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• v.19 no.2
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• pp.149-163
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• 2023

Affected by external factors, errors in time series data collected by sensors are common. Using the traditional method of constraining the speed change rate to clean the errors can get good performance. However, they are only limited to the data of stable changing speed because of fixed constraint rules. Actually, data with uneven changing speed is common in practice. To solve this problem, an online cleaning algorithm for time series data based on dynamic speed change rate constraints is proposed in this paper. Since time series data usually changes periodically, we use the extreme learning machine to learn the law of speed changes from past data and predict the speed ranges that change over time to detect the data. In order to realize online data repair, a dual-window mechanism is proposed to transform the global optimal into the local optimal, and the traditional minimum change principle and median theorem are applied in the selection of the repair strategy. Aiming at the problem that the repair method based on the minimum change principle cannot correct consecutive abnormal points, through quantitative analysis, it is believed that the repair strategy should be the boundary of the repair candidate set. The experimental results obtained on the dataset show that the method proposed in this paper can get a better repair effect.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.4
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• pp.179-191
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• 2017

The purpose of this study is to investigate the change of comprehension degree about learning satisfaction and capstone class by applying the subject which draws idea for team project task in college to creative capstone design program. The Capstone Design Program is designed to train fieldworkers with creative problem solving skills and is widely applied as a problem-solving course in team-based projects. In this paper, based on the case study of the 'fusion capstone design' operated in the first semester of 2015 ~ 2017, the capstone design course was established in the course of designing ideas for problem solving. The results of this study are as follows: First, the questionnaire about capstone design instruction process, instruction method, and learning achievement satisfaction were analyzed. As a result, understanding of capstone design was found to be higher than that of class before class, and satisfaction of performance course, method of teaching performance and learning outcome were obtained.

• Journal of the Korean Mathematical Society
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• v.50 no.1
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• pp.81-93
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• 2013

We consider a distributed optimal flux control problem: finding the potential of which gradient approximates the target vector field under an elliptic constraint. Introducing the Lagrange multiplier and a change of variables the Euler-Lagrange equation turns into a coupled equation of an elliptic equation and a reaction diffusion equation. The change of variables reduces iteration steps dramatically when the Gauss-Seidel iteration is considered as a solution method. For the elliptic equation solver we consider the Cell Boundary Element (CBE) method, which is the finite element type flux preserving methods.