• Journal of the Korean Chemical Society
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• v.48 no.2
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• pp.182-188
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• 2004

In this study, the effects of a four-stage problem-solving strategy emphasizing planning and checking stages were investigated. Two high school classes (N=55) were randomly assigned to either treatment or control group, and taught about two topics, 'gas' and 'solution' for 8 class hours. Teacher used the four-stage problem-solving strategy emphasizing planning and checking stages in the treatment group, and used traditional lecture in the control group. Two-way ANCOVA results revealed that the test scores of the treatment group were significantly higher than those of the control group in the problem-solving ability, especially in the subcategories of 'conceptual knowledge' and 'mathematical execution'. There was significant interaction between the instruction and the level of prior achievement in the 'satisfaction' of the learning motivation. The lower level students in the control group were more satisfied with chemistry class than those in the treatment group. There was no significant difference between the two groups in the scores of the awareness of metacognition. Educational implications are discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.25-30
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• 2016

It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

• Journal of the Korean Society for Library and Information Science
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• v.23
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• pp.63-106
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• 1992

The opening period of Korea was the period of modernisation amidst the conflicts between conservative and progressive sections with penetration of Western powers after 1876. With the opening modernisation accompanied modernisation of education. Missionary schools established by protestant missionaries played a crucial role in educational modernisation in the period of opening. In this article, the process of educational modernisation and the ways in which the ideas of democracy and equality were taught in the earliest schools, Paejae, Ewha, Kyoungsin and Chungsin are analysed through the method of bibliographical investigation of the textbooks used by these schools. No textbook prior to 1900 was found and in general there were no textbooks such as we know today. Usually English reading material and the Bible were the main teaching materials. Teachers kept their own copies of hand-written texts which were translated versions of American textbook. Since the same teacher taught in a number of schools, they shared same curriculum. In the early period, English Bible was taught so that English and the Bible lessons were not separated but gradually history and geography were added. Teaching of Hangul, and Korean history were added to encourage the sense of national identity and patriotism. In the case of Chungsin, for biology class, pupils were sent to Che-jung-won to learn human physiology, chemistry and physics, which shows an emphasis on science education. Vocational education was carried out; in the case of Paejae, a printing workshop was set up enabling students to earn some money at the same time as learning. Also in Kyungsin, skills of woodwork and basket weaving were stressed. Ewha also held a bazaar of the work made in sewing classes. Establishment of missionary schools brought about a great contribution in modernising Korean society and the Christian spiritual education of these schools lay the foundation for building democracy in Korea.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.406-409
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• 2008

We consider the problem of exploiting a taxonomy of propositionalized attributes in order to learn compact and robust classifiers. We introduce Propositionalized Attribute Taxonomy guided Naive Bayes Learner (PAT-NBL), an inductive learning algorithm that exploits a taxonomy of propositionalized attributes as prior knowledge to generate compact and accurate classifiers. PAT-NBL uses top-down and bottom-up search to find a locally optimal cut that corresponds to the instance space from propositionalized attribute taxonomy and data. Our experimental results on University of California-Irvine (UCI) repository data sets show that the proposed algorithm can generate a classifier that is sometimes comparably compact and accurate to those produced by standard Naive Bayes learners.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.320-334
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• 2010

Due to the global economic crisis and jobless growth, the problem of employment is becoming an important social issue. Fostering potential entrepreneurs with systematic education can be an alternative for resolving the jobless growth problem. Therefore, this study presents entrepreneurship subjects which are needed for designing a curriculum of the systematic entrepreneurship education. This study develops a questionnaire based on prior researches, and executes the survey of two focused groups comprised with a group of researchers lecturing subjects related with entrepreneurship and a group of executing an entrepreneurship consulting. The result of the study can be applied to design and run the curriculum in the universities, which consider introducing stage of entrepreneurship education. This study help a entrepreneurship department to bear the curriculum, and a direction of specialization.

• Communications of Mathematical Education
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• v.24 no.2
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• pp.345-363
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• 2010

The purpose of this study is to investigate and analyze informal knowledge of students who do not learn the conception of proportion and to identify how the informal knowledge can be used for teaching the conception of proportion in order to present an effective method of teaching the conception. For doing this, proportion was classified into direct and inverse proportion, and 'What are the informal knowledge of students?' were researched. The subjects of this study were 117 sixth-graders who did not have prior learning on direct and inverse proportion. A total eleven problems including seven for direct proportion and four for inverse proportion, all of them related to daily life. The result are as follows; Even though students didn't learn about proportion, they solve the problems of proportion using informal knowledge such as multiplicative reasoning, proportion reasoning, single-unit strategy etc. This result implies mathematics education emphasizes student's informal knowledge for improving their mathematical ability.

• Journal of the Korean Society for Library and Information Science
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• v.46 no.4
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• pp.5-25
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• 2012

The purpose of this study is to develop a measurement tool for the quality of information commons. Information commons is a physical, technological, social, and intellectual place where library users can experience various educational, research, and cultural activities. It is recently gaining popularity and several libraries have implemented it to help users share knowledge and interact with each other. It also intends to provide a place for collaboration, learning, and rest. Despite its benefits and usefulness, there is no measurement tool explicitly designed for the quality of information commons. This study used in-depth personal interview, compared prior studies, and conducted a pilot study to elicit library users' perceptions on information commons and factors influencing on the perceived quality of information commons. Groups of initial items were emerged through classifying and clustering key concepts in the data. Then, the validity of the items were verified through a pilot study. The findings of this study will be useful for developing more reliable and valid survey measurement tool.

• Journal of KIISE
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• v.43 no.8
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• pp.902-909
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• 2016

Question answering system (QA system) is a system that finds an actual answer to the question posed by a user, whereas a typical search engine would only find the links to the relevant documents. Recent works related to the open domain QA systems are receiving much attention in the fields of natural language processing, artificial intelligence, and data mining. However, the prior works on QA systems simply replace all words that are not in the training data with a single token, even though such unseen words are likely to play crucial roles in differentiating the candidate answers from the actual answers. In this paper, we propose a method to compute vectors of such unseen words by taking into account the context in which the words have occurred. Next, we also propose a model which utilizes inverse document frequencies (IDF) to efficiently process unseen words by expanding the system's vocabulary. Finally, we validate that the proposed method and model improve the performance of a QA system through experiments.

• Journal of Educational Research in Mathematics
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• v.13 no.3
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• pp.247-265
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• 2003

The purpose of this study is to analyze the essence of ratio concept from educational viewpoint. For this purpose, it was tried to examine contents and organizations of the recent teaching of ratio concept in elementary school text of Korea from ‘Syllabus Period’ to ‘the 7th Curriculum Period’ In these text most ratio problems were numerically and algorithmically approached. So the Wiskobas programme was introduced, in which the focal point was not on mathematics as a closed system but on the activity, on the process of mathematization and the subject ‘ratio’ was assigned an important place. There are some educational implications of this study which needs to be mentioned. First, the programme for developing proportional reasoning should be introduced early Many students have a substantial amount of prior knowledge of proportional reasoning. Second, conventional symbol and algorithmic method should be introduced after students have had the opportunity to go through many experiences in intuitive and conceptual way. Third, context problems and real-life situations should be required both to constitute and to apply ratio concept. While working on contort problems the students can develop proportional reasoning and understanding. Fourth, In order to assist student's learning process of ratio concept, visual models have to recommend to use.

• Journal of Educational Research in Mathematics
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• v.27 no.2
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• pp.171-189
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• 2017

By designing and applying the lesson helping to discover the power laws, we tried to investigate the characteristics on the class. To do this, we designed a discovery lesson on the power laws and applied to 54 8th grade students. As results, we could observe the overproduction of monotonous laws, tendency to vary the type of development and increase error to students without prior learning experience, and various errors. All participants failed to express the generalization of $a^m{\div}a^n$ and some participants expressed an incomplete generalization using variables partially for the base or power. We could also observe an error of limited generality or a representation error which did not use the equal sign or variables. In the survey of students, there were two contradictory positions to appeal to the enjoyment of the creation and to talk about the difficulty of creation. Based on such results, we discussed the pedagogical implications relating to the discovery of power laws.