• Education of Primary School Mathematics
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• v.4 no.2
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• pp.151-163
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• 2000

This research is the object to investigate these thing; how do teachers undertaking at the spot classrooms to recognize performance assessment and how do they decide to question and how go the present practiced state and what is the problem points in the present performance assessment. Additonal things of problem point like a research object are following; Lets look over recognition, actual situations and various problems for mathematics performance assessment of elementary school teachers. Concerning question papers, the problem largely lie in 4 regions, that is to say the recognition of performance assessment, the current state of affairs in practice, deciding questions and problems of putting theory into practices, of the 480 teachers-the object of our studies-about 380 returned our questionaire. However, as there were too many in the age range 30 to 40 are excluded 80, choosing 300 to us as data in our analysis.

• Coupled systems mechanics
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• v.3 no.3
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• pp.291-304
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• 2014

Paper discusess a dynamic engineering problem of a mass attached to a pendulum sliding along a cable. In this problem the pendulum mass and the cable are coupled together in a model described by a system of differential algebraic equations (DAE). In the paper we have presented formulation of the system of differential equations that models the problem and determination of the initial conditions. The developed model is general in a sense of free choice of support location, elastic cable properties, pendulum length and inclusion of braking forces. Examples illustrate and validate the model.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.11a
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• pp.3-8
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• 2003

Census data are usually provided at an aggregated level. However, the aggregated data are essentially arbitrary geographical areas. The areal units used to report census data have no natural or meaningful geographical identity. Unfortunately, this means that analyses of these area aggregations may be conditional upon the set of zones, which are presented. This effect is known as the modifiable areal unit problem (MAUP) and has two related aspects. First, scale effect is the variation in numerical results that occurs due to the number of zones used in an analysis. Second, results may also differ between different ways of aggregating exactly the same data to the same scale; this may be called the aggregation effect (Openshaw, 1984). This study aims to provide a practical tool for the study of MAUP. I have created a set of 91 areal units based on 280 basic units in Nonhyun-2 dong to solve zoning problem and scale problem. We can easily recognize the importance of areal classification as statistics were different according to areal classification.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.472-475
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• 1995

In this paper, we investigate so-called the falling cat problem. It is well known that a cat, when released from an upside down configuration starting from rest, is able to land on her feet without violating angular momentum conservation. This has being an interesting problem for engineers for a long time. We consider a model of a falling cat as connected two rigid columns, which is a nonholonomic system. We design the controller for it, using time- state control form of the model and exact linearization technique. Finally, we test the controller thorough simulation on the model of a falling cat.

• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.206-209
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• 1999

Conventional target tracking techniques are primarily based on Kalman filtering or probabilistic data association(PDA). But it is difficult to perform well under a high cluttered tracking environment because of the difficulty of measurement, the problem of mathematical simplification and the difficulty of combined target detection for tracking association problem. This paper deals with an analysis of target tracking problem using fuzzy-logic theory, and determines fuzzy rules used by a fuzzy tracker, and designs the fuzzy tracker by using fuzzy rules and Kalman filtering.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.5
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• pp.574-578
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• 1998

This paper considers the robust positive real problem for linear systems with linear fractional-type norm-bounded repeated scalar block parameter uncertainty. It is shown that the robust positive real problem can be converted into the standard positive real problem without uncertainty that can be used for the analysis of the given uncertain linear system and the synthesis of a controller that robustly stabilizes and achieves the extended strict positive realness property of the closed-loop transfer function. These results can be also applied to the linear system with general structured uncertainty containing repeated scalar block parameters and are extensions of the previous works that consider only norm-boundedness of the affine unstructured uncertainty.

• Journal of Aerospace System Engineering
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• v.2 no.3
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• pp.40-44
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• 2008

T-50 ECS(environment control system) was designed to have freezing protection for the condenser. However during the ground and flight test, the freezing problem was occurred. This paper deals with the analysis of the freezing problem and introduces anti-freezing design using ADI(Active De-Icing) logic to solve the condenser freezing problem of T-50 ECS

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.180-187
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• 1999

This document illustrates the relationship between the wire rod wrinkle defect and the roll caliber design. The wrinkle defect is caused by the incongruent rolling conditions of the roll caliber design, the roll adjustment, and the extracting temperature. In this document, we restrict the study scope to the roll caliber design's effect on wrinkle defect at the base of real condition of the No.2 Wire Rod mill, POSCO. There has been wrinkle defect problem in the No.2 Wire Rod Mill, POSCO for many years. The engineers of the wire rod mill have been making efforts to solve the problem. As one of the efforts, we take the samples of the wire rod in the each stands of the 2'nd wire rod mill and then analyze the samples. Through the analysis, we find out the problem of the roll caliber design. So, we suggest the roll caliber design method to be more effective to weaken the wrinkle defect.

• Phonetics and Speech Sciences
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• v.6 no.3
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• pp.149-153
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• 2014

In frequency domain ICA, the frequency bin permutation problem falls off the quality of separated signals. In this paper, we propose a new algorithm to solve the frequency bin permutation problem using the covariance of power ratio of separated signals in multi-channel FD-ICA. It makes use of the continuity of the spectrum of speech signals to check if frequency bin permutation occurs in the separated signal using the power ratio of adjacent frequency bins. Experimental results have shown that the proposed method could fix the frequency bin permutation problem in the multi-channel FD-ICA.

• Korean Journal of Child Studies
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• v.22 no.2
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• pp.113-132
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• 2001

In order to develop a model for better understanding of causal relationships in resiliency factors in families of children with disabilities, 200 families participated in this adaptation of the Resiliency Model of McCubbin and McCubbin(1993). The 6 latent variables included in the hypothesized model were family stress, family hardiness, family schema, community support, family problem-solving communication, and family adaptation. The models were developed on the basis of confirmatory factor analysis and compared using covariance structure modeling (LISREL). Adequate fitness of the model was observed. Family stress showed negative effect on family schema and on family hardiness. Family schema showed positive effect on community support and on family hardiness. Family hardiness showed positive effect on family problem-solving communication, and family problem-solving communication showed positive effect on family adaptation.