• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.2
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• pp.75-84
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• 2019

In this study, the random forest approach was used to predict the national mean rice yield of South Korea by using mean climatic factors at a national scale. A random forest model that used monthly climate variable and year as an important predictor in predicting crop yield. Annual yield change would be affected by technical improvement for crop management as well as climate. Year as prediction factor represent technical improvement. Thus, it is likely that the variables of importance identified for the random forest model could result in a large error in prediction of rice yield in practice. It was also found that elimination of the trend of yield data resulted in reasonable accuracy in prediction of yield using the random forest model. For example, yield prediction using the training set (data obtained from 1991 to 2005) had a relatively high degree of agreement statistics. Although the degree of agreement statistics for yield prediction for the test set (2006-2015) was not as good as those for the training set, the value of relative root mean square error (RRMSE) was less than 5%. In the variable importance plot, significant difference was noted in the importance of climate factors between the training and test sets. This difference could be attributed to the shifting of the transplanting date, which might have affected the growing season. This suggested that acceptable yield prediction could be achieved using random forest, when the data set included consistent planting or transplanting dates in the predicted area.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.10
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• pp.461-470
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• 2023

While speech animation generation employing deep learning has been actively researched for English, there has been no prior work for Korean. Given the fact, this paper for the very first time employs supervised deep learning to generate Korean speech animation. By doing so, we find out the significant effect of deep learning being able to make speech animation research come down to speech recognition research which is the predominating technique. Also, we study the way to make best use of the effect for Korean speech animation generation. The effect can contribute to efficiently and efficaciously revitalizing the recently inactive Korean speech animation research, by clarifying the top priority research target. This paper performs this process: (i) it chooses blendshape animation technique, (ii) implements the deep-learning model in the master-servant pipeline of the automatic speech recognition (ASR) module and the facial action coding (FAC) module, (iii) makes Korean speech facial motion capture dataset, (iv) prepares two comparison deep learning models (one model adopts the English ASR module, the other model adopts the Korean ASR module, however both models adopt the same basic structure for their FAC modules), and (v) train the FAC modules of both models dependently on their ASR modules. The user study demonstrates that the model which adopts the Korean ASR module and dependently trains its FAC module (getting 4.2/5.0 points) generates decisively much more natural Korean speech animations than the model which adopts the English ASR module and dependently trains its FAC module (getting 2.7/5.0 points). The result confirms the aforementioned effect showing that the quality of the Korean speech animation comes down to the accuracy of Korean ASR.

• The Journal of Korean Association of Computer Education
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• v.8 no.1
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• pp.13-23
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• 2005

In this study, messages from on-line discussions of 28 preservice teachers were analyzed based on social constructivist learning theory. After preliminary discussion session for a week, small group discussions were conducted every single week with different topics during 4 weeks. One transcript with most frequent messages in each topic was selected, and a total of 72 messages were analyzed. Discussion topics were the issues related to the nature of science. The Interaction Analysis Model for Examing Social Construction of Knowledge in Computer Conferencing was used for the analysis. Analysis of the messages indicated that 'sharing information' was the most frequent, and that 'discovering/exploring dissonance' and 'negotiation of meaning/co-construction of knowledge' were the nex. However, messages of 'testing and modification of proposed synthesis' and 'testing and application of newly constructed meaning' were found to be rare. This result indicated that students' interaction through on-line discussion did not reach to the social construction of knowledge.

• Journal of Digital Contents Society
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• v.19 no.6
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• pp.1161-1167
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• 2018

The development of machine learning has enabled machines to perform delicate tasks that only humans could do, and thus many companies have introduced machine learning based translators. Existing translators have good performances but they have problems in number translation. The translators often mistranslate numbers when the input sentence includes a large number. Furthermore, the output sentence structure completely changes even if only one number in the input sentence changes. In this paper, first, we optimized a neural machine translation model architecture that uses bidirectional RNN, LSTM, and the attention mechanism through data cleansing and changing the dictionary size. Then, we implemented a number-processing algorithm specialized in number translation and applied it to the neural machine translation model to solve the problems above. The paper includes the data cleansing method, an optimal dictionary size and the number-processing algorithm, as well as experiment results for translation performance based on the BLEU score.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.61-69
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• 2016

Recently, university education is changing from content- centered to learner - centered education not to deliver knowledge unilaterally but to help student to cultivate their skills to discover and apply knowledge for themselves. It means that students' cognitive or emotional development is being emphasized. Also, because of universities' quantitative expansion, more strict evaluation on professors' research result, or conversion to a departmental system in a university organization, it has become a crucial issue for undergraduates to adapt to college life successfully. Along with this trend of university education, an academic advising system is becoming one of the most important areas in it as in not only provides students with necessary academic information but also helps them adapt to college life by developing their potentials and integrating their career and life plans. Therefore this study is going to examine the status of academic advising systems in US universities, investigate how Dongguk University's Paramita college operates its academic advising system, and find out way to establish academic advising system in Korean universities.

• KIISE Transactions on Computing Practices
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• v.22 no.7
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• pp.338-343
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• 2016

Today, opinion reviews on the Web are often used as a means of information exchange. As the importance of opinion reviews continues to grow, the number of issues for opinion spam also increases. Even though many research studies on detecting spam reviews have been conducted, some limitations of gold-standard datasets hinder research. Therefore, we introduce a new dataset called "Paraphrased Opinion Spam (POS)" that contains a new type of review spam that imitates truthful reviews. We have noticed that spammers refer to existing truthful reviews to fabricate spam reviews. To create such a seemingly truthful review spam dataset, we asked task participants to paraphrase truthful reviews to create a new deceptive review. The experiment results show that classifying our POS dataset is more difficult than classifying the existing spam datasets since the reviews in our dataset more linguistically look like truthful reviews. Also, training volume has been found to be an important factor for classification model performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.629-641
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• 2016

This study analyzed the use of the phenomenological method proposed by Colaizzi (1978) in order to understand the meaning of block system class experiences in nursing students. Furthermore, this study provides primal data to improve curriculum efficiency. The data were collected from 18 participants who were students at a nursing university in the city of G from 20th of June to 10th of July 2015. This study investigated nursing student's block system class experience. The study results show six theme clusters consisting of 'Discomfort', 'Unsystematic study', 'Holding back an urge', 'Ever intensifying relationship', 'New discovery', and 'Chance for development', 17 themes, and 42 sub themes, which are included in those clusters in 58 configured meanings. This demonstrates that nursing students could reestablish their resolve for personal betterment and realize the importance of managing time by finishing the procedure with their best efforts although they suffer from physical and psychological inconvenience due to massive amounts of learning and assignment. These results indicate the need for development of stress management and an emotional support program based on the experience of nursing students.

• Journal of The Korean Association of Information Education
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• v.18 no.4
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• pp.471-482
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• 2014

It is known that the smart education has a positive impact of critical thinking skills and problem solving, communication and collaboration, creativity and innovation in the 21st century. However, some people concern about the adverse effects of smart education such as smart devices addiction and health problems. In this study, we conducted the adverse effects of education using smart devices on students. The questionnaire survey was conducted and analyzed for students in 9 schools at A city(four elementary schools, three middle schools, two high schools) that are receiving smart education. The types of adverse effects of smart education includes smartphone addiction, lack of information ethics, health problems, and lack of social and learning ability. We showed the differences each item compared among elementary school, middle school and high school about adverse effects of smart education. The result of survey didn't have any adverse affect of smart education such as internet addiction or smartphone addiction. However in order to protect the copyright, the school needs to fight against indiscriminated downloads and perform the information ethics education. Plus we surely need to be more open-minded in reading and exercise at school and home.

• Journal of The Korean Association For Science Education
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• v.31 no.5
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• pp.815-826
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• 2011

The purpose of this study was to analyze professionals' opinion about science education using history of science. For this purpose, we surveyed professionals in the field of science education and history of science (HOS), 30 professionals in the first survey and 84 professionals in the second survey. The results are as follows: First, they focused the nature of science in the science education using HOS. Second, they suggested the need for development of teaching and learning materials for using HOS in class. Third, they proposed action-based science teacher training for using HOS. Fourth, there appeared differences of professionals' opinion in some areas. Lastly, they did not make a high agreement in the need of history of eastern science including history of Korean science. It is necessary to develop teaching and learning materials in the history of eastern science.

• Journal of Educational Research in Mathematics
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• v.27 no.3
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• pp.351-373
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• 2017

The meanings of division don't change and rather are connected from whole numbers to rational numbers. In this respect, connecting division of natural numbers, division of fractions, and division of decimal numbers could help for students to study division in meaningful ways. Against this background, the units of division of fractions and division of decimal numbers in fifth grade were redesigned in a way for students to connect meanings of division and procedures of division. The results showed that most students were able to understand the division meanings and build correct expressions. In addition, the students were able to make appropriate division situations when given only division expressions. On the other hand, some students had difficulties in understanding division situations with fractions or decimal numbers and tended to use specific procedures without applying diverse principles. This study is expected to suggest implications for how to connect division throughout mathematics in elementary school.