• Journal of The Korean Association For Science Education
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• v.19 no.4
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• pp.674-683
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• 1999

The purpose of this study was to compare the ideas of pupils with that of the scientists about controlling and identifying of variables, in the two cases: open or guided inquiry. The subjects were the 7th grade boys and girls in a school, in Seoul, Korea. For the guided inquiry, the problems were given by the experiments of pupils' text. Pupils were asked to identify the variables in the experiments. For the open inquiry, pupils set their own inquiry problem. The pupils whose marks are within upper one-third of three classes were chosen. Pupils' ideas on variables were investigated in the design of experiment for their problems. In that, questionnaire developed by researchers was used. In the former, many of the pupils identify just only one variable despite of the fact there were two independent or dependent variables in the experiments. In the latter, the number of independent variables increased two or three. However, pupils do not control independent variables: they vary two independent variables simultaneously in the design of experiment. From these, we compared the pupils' ideas on variables with the scientists'

• Journal of Science Education
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• v.36 no.2
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• pp.251-262
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• 2012

In this study, we develop 15 learning programs to enhance the variable identification and control abilities for the middle school students and analyze the effect of the programs applied to the class. To increase the learning effect of the variable identification and control abilities, we design the programs so that the students can monitor their thinking processes and also they can evaluate the results from their cognitive activities objectively. We analyze the effect of the programs applied to the class and the results show that the test group, which uses the program, marks higher scores in the variable identification abilities compared to the control group. Also, the test group has the increased level of logic to control the variables. Especially, the effect is higher with the students who do not have any logic to control the variables. From the results, we know that it is possible to improve the variable identification and control abilities of the students through the meta-cognitive learning programs developed by us. Furthermore, the results show that the score of variable control abilities positively correlate with that of meta-cognitive level. It means that the meta-cognitive strategy meaningfully increases the variable control abilities of middle school students.

• Korean journal of communication and information
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• v.49
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• pp.20-38
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• 2010

This paper was attempting to identify determinants of media repertoires based on new services and technologies. Using the regression and discriminant models, this study examined determinants that included five independent factors such as the degree of innovation, social networks, social influences, demographic variables and media uses. The analyses revealed that all of independent variables except the degree of innovation were significant determinants of media repertoires. Secondly, the results of discriminant analyses showed that terrestrial television use, age, disposable income were significant factors discriminating new media service adopters from the sample. For new media related technologies adopters, family income, and media uses such as newspaper, Internet and radio were significant discriminant variables.

• 한국노년학
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• v.31 no.1
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• pp.79-96
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• 2011

The purpose of this study was to search the clustering and variables in discriminating the groups by the level of the loss experience and ego-integrity among the elderly. In addition, the study aimed to confirm the moderating effects of variables related to resilience in the relationship between a loss experience and ego-integrity. The subjects were 245 elderly aged 60 or above, most of whom were socially active with comparatively high education levels. Six individual variables(physical self-efficacy, general self-efficacy, social self-efficacy, existential spirituality, religious spirituality, optimism) and five environmental variables(emotional support, instrumental support, informational support, appraisal support, social activity) were used in the study. The results of the study are as follows. To data analysis, ANOVA, Stepwise Discriminant analysis, Cluster analysis, Regression analysis and Two-way analysis of variance was employed. First, the subjects were 4 cluster into overcome group, crisis group, stable group and vulnerable group according to the level of loss experience and ego-integrity. Second, optimism, physical self-efficacy, existential spirituality and emotional support were seen to be significant variables in discriminating the groups. Third, the ego-integrity became higher as the variables related to resilience were increased.

• Communications for Statistical Applications and Methods
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• v.4 no.3
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• pp.617-628
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• 1997

시계열 자료의 변이상태(transition status)에 대한 판별은 여러 분야에서 연구되고 있다. 하지만 변압기의 진동신호와 같이 특정한 시계열모형을 적합시키기 힘든 자료는 변이 상태에 대한 판별이 쉽지 않다. 본 논문에서는 정상적인 변압기에서 발생하는 진동신호에 대하여 각 주기별 최대값, 자기상관계수 및 편자기상관계수 등의 경험적 표본분포를 연구한 후, 이를 이용한 관리도를 만들어 변압기 진동신호의 변이상태에 대한 판별을 하였다. 이 방법은 품질관리의 관리도 이론을 시계열자료에 응용한 것으로 비정상적인 변압기 진동신호의 판별에 만족스러운 결과를 가져왔다.

• Journal of Gifted/Talented Education
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• v.24 no.4
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• pp.679-701
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• 2014

As the validity issue of teacher nominations for the identification of gifted students has been raised recently, this study purports to test the validity of teacher nominations for selecting scientifically gifted students. As the criterion variables, domain specific traits such as science creative problem solving skills and science attitudes and domain general characteristics such as divergent thinking skills, creative attitudes, intrinsic motivation, and leadership were analyzed. Scientifically gifted students, potentially gifted students who had never been enrolled in gifted programs but were nominated as the scientifically gifted by teachers, and general class students participated in the study. The results of ANOVA showed that there were significant differences in all variables but originality factors of the TTCT and science creative problem solving skill test between gifted/nominated students and general class students; gifted/nominated students were significantly superior in these variables to general class students. The discriminant functions analysis yielded a discriminant function that significantly discriminated between gifted/nominated and general class students. Variables loaded on the discriminant function were science creative problem solving skills except for the originality subfactor, and science efficacy. These results imply that while teachers are likely to consider adaptation-oriented academic excellency related to logical thinking skills, problem solving skills, and science performance when nominating students, they may ignore the innovation-oriented property which is indicated as the fluency and originality factors of TTCT. Also, the criteria of teacher nominations are presumed to be congruent with the selection criteria of the gifted education program which pursued academic excellency as the educational goal. This suggests that with such criteria, high performing students in the science area can be sufficiently identified by teachers with no further identification procedures or/and tests.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.301-301
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• 2022

본 연구는 운영 조건이 달라짐에 따라 회전수가 변하는 기기의 정상적 가동 여부와 고장 종류를 판별하기 위한 인공지능 알고리즘의 적용을 다루고 있다. 회전수가 변하는 장비로부터 계측된 상태 모니터링 센서의 신호는 비정상(non-stationary)적 특성이 있으므로, 상태 신호의 한계치가 고장 판별의 기준이 되기 어렵다는 점을 해결하고자 하였다. 정상 가동 여부는 이상 감지에 효율적인 오토인코더 및 기계학습 알고리즘을 적용하였으며, 고장 종류 판별에는 기계학습법과 합성곱 기반의 심층학습 방법을 적용하였다. 변하는 회전수와 연계된 주파수의 비정상적 시계열도 적절한 고장 특징 (Feature)로 대변될 수 있도록 시간 및 주파수 영역에서 특징 벡터를 구성할 수 있음을 예제로 설명하였다. 차원 축소 및 카이 제곱 기법을 적용하여 최적의 특징 벡터를 추출하여 기계학습의 분류 알고리즘이 비정상적 회전 신호를 가진 장비의 고장 예측에 활용될 수 있음을 보였다. 이 과정에서 k-NN(k-Nearest Neighbor), SVM(Support Vector Machine), Random Forest의 기계학습 알고리즘을 적용하였다. 또한 시계열 기반의 오토인코더 및 CNN (Convolution Neural Network) 적용하여 이상 감지와 고장진단을 수행한 결과를 비교하여 제시하였다.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.95-97
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• 2010

최근 겨울철 온난화 경향이 뚜렷해지면서 강수형태가 비로 내리는 경우가 잦아지고 있다. 또한 대륙고기압이 확장할 때는 기압골의 영향으로 강우에서 강설로 변하는 예가 종종 나타나고 있다. 강수유형의 판단은 겨울철 중요한 예보요소 중 하나로 본 연구는 중서부지방의 2010년 2월 4일부터 12일까지의 사례기간동안 일기도, AWS관측자료, 위성, KLAPS(층후, 빙결고도, 상당온위) 자료를 바탕으로 하여 강우에서 강설로 변하는 강수형태를 분석한 것이다.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.160-165
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• 1998

Current discriminating technique of rice variety is known to be not objective till this time because of depending on naked eye of well trained inspector. DNA finger print method based on genetic character of rice has been indicated inappropriate for on-site application, because the method need much labor and skilled expert. The purpose of this study was to develops the identification technique of polished rice varieties using CCD camera images. To minimize the noise of the captured image, thresholding and median filtering were carried out, and edge was extracted from the image data. Image data after pretreatment of normalize and FFT(fast fourier transform) were used for library model and feedforward backpropagation neural network model. Image processing technique using CCD camera could discriminate the variety of rice with high accuracy in case of quite different rice of shape, but the accuracy was reached at 85% in the similar shape of rice.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.5
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• pp.29-35
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• 2010

In this paper, We implemented discriminating system for various surround illuminants using photo sensor. To discriminate surround illuminants of display device we implemented discriminating system using photo sensor which has output of Ye and Cy. Experimental results shows that we could discriminate surround illuminants by output voltage ratio (Ye/Cy) of photo sensor in the variable luminous intensity of surround illuminants.