• KIPS Transactions on Software and Data Engineering
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• v.6 no.11
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• pp.527-536
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• 2017

With the recent development of smart grid industry, the necessity for efficient EMS(Energy Management System) has been increased. In particular, in order to reduce electric load and energy cost, sophisticated electric load forecasting and efficient smart grid operation strategy are required. In this paper, for more accurate electric load forecasting, we extend the data collected at demand time into high time resolution and construct an artificial neural network-based forecasting model appropriate for the high time resolution data. Furthermore, to improve the accuracy of electric load forecasting, time series data of sequence form are transformed into continuous data of two-dimensional space to solve that problem that machine learning methods cannot reflect the periodicity of time series data. In addition, to consider external factors such as temperature and humidity in accordance with the time resolution, we estimate their value at the time resolution using linear interpolation method. Finally, we apply the PCA(Principal Component Analysis) algorithm to the feature vector composed of external factors to remove data which have little correlation with the power data. Finally, we perform the evaluation of our model through 5-fold cross-validation. The results show that forecasting based on higher time resolution improve the accuracy and the best error rate of 3.71% was achieved at the 3-min resolution.

• School Mathematics
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• v.11 no.3
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• pp.389-413
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• 2009

This thesis assumes that the teaching objective of the Probability unit of the 8th grade textbook under the 7th National Curriculum is to enhance the ability to analyze and utilize informations. And we examine them if this point of view is fully reflected. Based on the analysis of the textbook analysis, followings are found. 1) It is necessary to emphasize more enumerating all possible cases and to induce formulae counting the number of possible cases through organizing them 2) The probability is to be decribed more clearly as a likelihood of events and to be introduced and followed through various students' experiences and the relative frequencies. Less emphasis on probability computations, while more emphasis on probability comparisons of events are recommended. 3) The term "influential events"(a kind of stochastic correlation) is ambiguous. It is necessary to make clear what it means at tile level of the 8th grade or to discard it for it is to be learned at the 10th grade again. Especially, contingency table has been introduced at the 9th grade under the 7th National Curriculum. 4) Uses of the likelihood principle in making a decision and in learning the reliability of it should be encouraged. And students are to team the hazard of transitive inferences in probability comparisons. As a consequence of above, we feel that textbook authors and related stakeholder are to be more serious about the behavioral changes of students that may come along with the didactics of specific contents of school mathematics.

• Journal of Korean society of Dental Hygiene
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• v.9 no.2
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• pp.137-146
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• 2009

In pediatric dentistry, sedation therapy is one of methods for managing children's behavior, and various types of sedation therapy are being used. Thus, this study surveyed the awareness of and satisfaction with sedation therapy in 204 parents who visited the Pediatric Dentistry using a self-administered questionnaire during the period from June to December 2008 in order to get information necessary in behavior management for pediatric patients, and obtained results as follows. 1. The most common path of learning about sedation therapy was dentistry (49.5%), and the most common reason for choosing sedation therapy was 'The child was young'(42.3%), which was followed by 'The child is too afraid'(18.8%), 'There are many teeth to be treated'(16.0%), 'To adjust the number of visits'(11.3%), and 'For behavior management'(3.1%). 2. Most of the parents felt anxiety about sedation therapy, and the reasons for the anxiety were 'The child was young'(33.0%), 'Worry about side effects'(31.3%), 'Worry about recovery of consciousness'(25.7%), 'Worry about the blunting of intellectual abilities'(7.6%), and others (2.4%). 3. Satisfaction with sedation therapy was higher in men than in women, and was high in order of 'Stationing of an anesthetist', 'One time completion of treatment', and 'Cautions'. Statistically significant difference was observed between men and women only in question "Have you ever heard about sedation therapy?"(p=0.018). 4. According to age, satisfaction with sedation therapy was highest in parents whose child was less than 48 months old. Satisfaction was high in order of 'Stationing of an anesthetist', 'One time completion of treatment', and 'Cautions', 'Choice of sedation therapy', and statistically significant difference was observed according to age only in question "Have you ever heard about sedation therapy?"(P=0.005). 5. Positive correlation was observed among questions on satisfaction with sedation therapy. In the survey on the awareness of and satisfaction with sedation therapy in parents visiting the dentistry, awareness and satisfaction were generally high with regard to the parents' choice of sedation therapy, but many of the parents answered that they chose sedation therapy and felt anxiety because their child was young. The results of this study need to be considered for behavior management in pediatric dentistry and there should be systematic education and promotion of sedation therapy.

• Ecology and Resilient Infrastructure
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• v.7 no.2
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• pp.114-125
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• 2020

Despite the various artificial neural networks that have been developed, most of the discharge models in previous studies have been developed using deep neural networks. This study aimed to develop a discharge model using a convolution neural network (CNN), which was used to solve classification problems. Furthermore, the applicability of CNN was evaluated. The photographs (pictures or images) for input data to CNN could not clearly show the characteristics of the study area as well as precipitation. Hence, the model employed in this study had to use numerical images. To solve the problem, the CN of NRCS was used to generate images as input data for the model. The generated images showed a good possibility of applicability as input data. Moreover, a new application of CN, which had been used only for discharge prediction, was proposed in this study. As a result of CNN training, the model was trained and generalized stably. Comparison between the actual and predicted values had an R² of 0.79, which was relatively high. The model showed good performance in terms of the Pearson correlation coefficient (0.84), the Nash-Sutcliffe efficiency (NSE) (0.63), and the root mean square error (24.54 ㎥/s).

• Journal of the Korean Home Economics Association
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• v.43 no.5 s.207
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• pp.183-198
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• 2005

The purpose of this study was to discuss the relationship between Korean people's normative sense of the traditional filial piety and their affiliation with relatives. For this purpose, the researcher reviewed ethics books during the Chosun dynasty such as Naehoon Women's Ethics), Dongmongsonsup (Children's Cardinal Moral Principles) ,Kyokmongyokyol (Juvenile's Learning) and Gyuenyoso (Instructions for Daughters of Marriageable Age), Based on this review a questionnaire was designed. For the survey,566 returned questionnaires from married people between their 20's and 70's living in Seoul and Wonju Si were sampled The collected data were analyzed using the SAS program for means and SDs of each area in order to examine the overall tendency, and were subject to one-way ANOVA to determine the relationship between their normative sense of the traditional filial piety and their affiliations with relatives depending on their demographic variables, In addition to this correlation analysis, the data underwent regression analysis to determine the significant factors affecting the subjects' sense of filial piety and their affiliation with relatives. The results of this study can be summarized as follows ; First, the subjects were found to have a normal or higher sense of filial piety in overall terms, which suggests that the Korean morality of filial piety may be positive. In particular, the subjects' sense of filial piety was higher for living parents than for dead ones. Namely, they wanted to give more respect, honor and support to their parents than give a cordial funeral or memorial service to deceased parents. Second, older Koreans were more aware of filial piety, and men were more conscious of filial piety than women. Buddhists or atheists tended to be more faithful to their parents. Generally, those with lower academic background and living with larger families had a higher normative sense of filial piety. On the other hand, those in their 60's and 70's were most affiliated with their relatives, while youth and middle-aged people were less affiliated with their relatives. Men were more affiliated with their relatives than women, and first sons or daughters were more affiliated with their relatives. Besides, those living with larger families were more affiliated with their relatives. Third, the subjects' normative sense of filial piety, particularly for deceased parents, was highly correlated with their affiliation with relatives, and such a normative sense of filial piety was most conspicuous in their funeral rites.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.277-284
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• 2020

To increase the utilization of the intelligent methodology of smart farm management, estimation modeling techniques are required to assess prior examination of crops and environment changes in realtime. A mandatory environmental factor such as CO₂ is challenging to establish a reliable estimation model in time domain accounted for indoor agricultural facilities where various correlated variables are highly coupled. Thus, this study was conducted to develop an artificial neural network for reducing time complexity by using environmental information distributed in adjacent areas from a time perspective as input and output variables as CO₂. The environmental factors in the smart farm were continuously measured using measuring devices that integrated sensors through experiments. Modeling 1 predicted by the mean data of the experiment period and modeling 2 predicted by the day-to-day data were constructed to predict the correlation of CO₂. Modeling 2 predicted by the previous day's data learning performed better than Modeling 1 predicted by the 60-day average value. Until 30 days, most of them showed a coefficient of determination between 0.70 and 0.88, and Model 2 was about 0.05 higher. However, after 30 days, the modeling coefficients of both models showed low values below 0.50. According to the modeling approach, comparing and analyzing the values of the determinants showed that data from adjacent time zones were relatively high performance at points requiring prediction rather than a fixed neural network model.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.245-252
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• 2016

The purpose of this study is to make up for missing of weather informations from ASOS and AWS using artificial neural networks. We collected temperature, relative humidity and wind velocity for August during 5-yr (2011-2015) and sample designed artificial neural networks, assuming the Seoul weather station was missing. The result of sensitivity study on number of epoch shows that early stopping appeared at 2,000 epochs. Correlation between observation and prediction was higher than 0.6, especially temperature and humidity was higher than 0.9, 0.8 respectively. RMSE decreased gradually and training time increased exponentially with respect to increase of number of epochs. The predictability at 40 epoch was more than 80% effect on of improved results by the time the early stopping. It is expected to make it possible to use more detailed weather information via the rapid missing complemented by quick learning time within 2 seconds.

• Journal of dental hygiene science
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• v.16 no.2
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• pp.157-164
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• 2016

The purpose of this study was to evaluate the association between oral health-related quality of life and school life satisfaction in high school students. A questionnaire-based survey was conducted on high school students in Daegu, South Korea from November to December, 2015, and final data from 432 students was analyzed. Analysis of oral health-related quality of life in terms of general characteristics showed that both academic achievement and stress were significant factors (p<0.05). With respect to school life satisfaction, academic achievement was found to be a highly significant influencing factor (p<0.01). Correlation analyses of oral health-related quality of life with various factors of school life satisfaction showed positive correlations with personal relationships, educational learning environment, social support. Regression analysis of school life satisfaction showed that academic achievement and oral health-related quality of life were influencing factors. These results indicate that oral health-related quality of life may play a significant role in school life satisfaction.

• Journal of the Korean earth science society
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• v.38 no.1
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• pp.91-104
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• 2017

The purposes of this study were to analyze high school students' understanding about the Earth system and systems thinking process, and to develop science writing programs designed to assess students' understanding about themes of Earth Science such as global warming, volcanoes, and desertification. A total of 8 $11^{th}$ grade students from general high schools participated in the writing program and draw the causal maps. The methods of this study are as follows. First, DAET-C was used to investigate the way of students' understanding about the Earth systems. What the students' best understood was the component of the Earth systems followed by the interaction of the Earth systems and the scientific literacy of Earth science. Second, feedback circulations on the causal maps were found in four students in global warming section, one student in volcanic eruption section, and four students in desertification section, which means that systems thinking was not largely employed by the students. Consequently, the student participants understood that the global change was happening in correlation with complex concepts and factors, but they were short of using systems thinking in their science study. Therefore, the result of this study suggests that more studies be conducted to develop systems thinking in Earth Science learning through science writing programs.

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.189-201
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• 2009

The purpose of this study was to find out whether scientifically creative students were selected as science-gifted class students and whether their creativity improved after class for the science-gifted students by comparing the science gifted class students to general class students in the first grade of high school. This was achieved by comparing science-gifted class students with general ones on creative personality and creative thinking ability. For this study, science-gifted class students and general class students were surveyed using Khatena-Torrance creative perception inventory and Torrance test of creative thinking with words of form A, before and after class for the science-gifted group. The results showed that science-gifted class students scored significantly higher than general class students on the creative personality. However, there was no significant difference between the two groups in their creative thinking ability. Also, in this study, the sub-factors of creative personality and those of creative thinking ability showed very low levels of correlation, which implies that the two variables are highly independent. In addition, science-gifted class students did not show significant improvement in their scores on the creative personality and the creative thinking ability after class. Therefore, further research and development on the selection of science-gifted students and teaching-learning methods which can improve the creativity of these students are needed.