• Communications for Statistical Applications and Methods
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• v.30 no.2
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• pp.119-133
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• 2023

With the rapid growth of the economy and fossil fuel consumption, the concentration of air pollutants has increased significantly and the air pollution problem is no longer limited to small areas. We conduct statistical analysis with the actual data related to air quality that covers the entire of South Korea using R and Python. Some factors such as SO₂, CO, O₃, NO₂, PM₁₀, precipitation, wind speed, wind direction, vapor pressure, local pressure, sea level pressure, temperature, humidity, and others are used as covariates. The main goal of this paper is to predict air quality index (AQI) spatio-temporal data. The observations of spatio-temporal big datasets like AQI data are correlated both spatially and temporally, and computation of the prediction or forecasting with dependence structure is often infeasible. As such, the likelihood function based on the spatio-temporal model may be complicated and some special modelings are useful for statistically reliable predictions. In this paper, we propose several methods for this big spatio-temporal AQI data. First, random effects with spatio-temporal basis functions model, a classical statistical analysis, is proposed. Next, neural networks model, a deep learning method based on artificial neural networks, is applied. Finally, random forest model, a machine learning method that is closer to computational science, will be introduced. Then we compare the forecasting performance of each other in terms of predictive diagnostics. As a result of the analysis, all three methods predicted the normal level of PM_2.5 well, but the performance seems to be poor at the extreme value.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.154-155
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• 2023

The International Convention on Standards for Training, Certification, and Watchkeeping of Seafarers (STCW) outlines the qualifications that maritime cadets must meet in order to serve as merchant marine officers. Maritime English is one of the most essential qualifications for STCW, and each national authority is implementing Maritime English education that complies with national and international regulations. In this study, an English proficiency background survey was conducted to investigate the factors related to the Maritime English skills and competencies. In line with this, maritime cadets utilized the Standard Maritime English Communication Phrases (SMCP) learning platform to track their learning progress and its efficacy. This study examined the applicability of the automatic scoring platform for Maritime English education, as well as its future potential for widespread use in the maritime education field.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.431-441
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• 2023

In a good class, the elements that make up the class are organically related as a system. The goal of the class is to foster the ability of students to fully understand the educational content of the subject and then apply it to their professional areas. Therefore, for ideal classes, it is necessary to design students to acquire the necessary theories and apply them practically. The question We always ask ourselves during lectures is how to effectively give large-scale lectures for students. This is also the concern of all professors in charge of large-scale lectures opened across various major fields. Now is the time to find ways to effectively give lectures on a large scale. We studied how it is most effective to design and implement various factors such as lectures, presentation and group organization, assignment, group presentation, professor's group presentation guidance, lecture materials posting, questions and answers, group presentation feedback, final report writing, and grade calculation.

• Korean Journal of Comparative Education
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• v.27 no.1
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• pp.247-284
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• 2017

The purpose of this study is to analyze firm's motivation of participating and investing in apprenticeship in Germany and Korea, and to investigate institutional factors influencing firm's motivation. By comparing institutional factors of the two countries, it aims to drawing out policy implications for improving Korean apprenticeship. The main method for data collection was comprehensive literature review on international organizations, each countries' government and research institutes' policy materials, statistical data, research outputs and media resources related to each countries' apprenticeship. Considering whether firm's motivation for participating and investing in apprenticeship is production-oriented or investment-oriented, Germany is more inclined to investment motivation with firm's covering net cost during apprenticeship period. On the other hand, Korea is more inclined toward production orientation with firm's expectation of gaining net profit during the training period. Why is firm's training motivation different in these two countries? The author tried to find the reason from the difference of institutional factors of the countries by dividing institutional factors into 4 categories: context(tripartite relations, legal framework), input (flexibility of the system, government incentive), process(training contents, training duration, quality assurance), and output(completion/retention rate, apprentice's productivity). The key implication from the comparative analysis of institutional factors is that it is necessary to enforce companies to have "accountability" on the minimum critical elements, but also to ensure them to have "autonomy" on the rest of the elements.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.572-583
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• 2019

This study sought to find out what the most ideal and appropriate native English speakers-Korean English teacher cooperative class model and the defining factors for organizing effective cooperative classes in the English education environment of our country. To achieve this goal, a total of 165 sixth graders of five elementary schools in Seoul were subject to the study. For about a month from April 1 to April 30, 2019, the survey and statistical analysis were conducted, including multiple return analysis, correlation analysis, cross analysis, and t/F verification. In summary, the results of the study are as follows. First, it was found that among the recognition of cooperative classes between native English speakers and Korean English teachers, it affected the defining factors in the order of class-related skills, task orientation, teaching-learning strategies, and motivation. Second, based on learner characteristics, the difference in perception of cooperative classes between native English speakers and Korean English teachers was verified, and the perception of native-Korean English teachers' cooperative classes was different depending on gender and the type of English cooperative classes currently participating, but the recognition of native-Korean English-Korean English cooperative classes, which were statistically significant, was not confirmed. Third, according to learner characteristics, the difference in the definition factors of the learner was verified and the difference between the sexes occurred, but the learner-defined factors according to the current type of English cooperative class did not occur. Also, there was no difference in the definition factors of scholars according to the type of English cooperative classes desired.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.672-682
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• 2020

The Korea Nowadays, which is research on digital twin technology for efficient operation in various industrial/manufacturing sites, is being actively conducted, and gradual depletion of fossil fuels and environmental pollution issues require new renewable/eco-friendly power generation methods, such as wave power plants. In wave power generation, however, which generates electricity from the energy of waves, it is very important to understand and predict the amount of power generation and operational efficiency factors, such as breakdown, because these are closely related by wave energy with high variability. Therefore, it is necessary to derive a meaningful correlation between highly volatile data, such as wave height data and sensor data in an oscillating water column (OWC) chamber. Secondly, the methodological study, which can predict the desired information, should be conducted by learning the prediction situation with the extracted data based on the derived correlation. This study designed a workflow-based training model using a machine learning framework to predict the pressure of the OWC. In addition, the validity of the pressure prediction analysis was verified through a verification and evaluation dataset using an IoT sensor data to enable smart operation and maintenance with the digital twin of the wave generation system.

• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1367-1384
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• 2013

The purpose of this study was to develop a Science Academic Emotion Scale for Elementary Students. To make a scale, authors extract a core of 14 emotions related to science learning situations from Kim & Kim (2013) and literature review. Items on the scale consisted of 14 emotions and science learning situations. The first preliminary scale had 174 items on it. The number of 174 items was reduced and elaborated on by three science educators. Authors verified the scale using exploratory factor analysis, confirmatory factor analysis, inter-item consistency and concurrent validity. The second preliminary scale consisted of 141 items. The preliminary scale was reduced to seven factors and 56 items by applying exploratory factor analysis twice. The seven factors include: enjoyment contentment interest, boredom, shame, discontent, anger, anxiety, and laziness. The 56 items were elaborated on by five science educators. The scale with 56 items was fixed with seven factors and 35 items to get the final scale by applying confirmatory factor analysis twice. Except for Chi-square and GFI (Goodness of Fit Index), other various goodness of fit characteristics of the seven factors and 35 items model showed good estimated figures. The Cronbach of the scale was 0.85. The Cronbach of seven factors are 0.95 in enjoyment contentment interest, 0.81 in boredom, 0.87 in shame, 0.82 in discontent, 0.87 in anger, 0.77 in anxiety, 0.81 in laziness. The correlation coefficient was 0.59 in enjoyment contentment interest, 0.54 in anxiety, 0.42 in shame, and 0.28 in boredom, which were estimated using the Science Academic Emotion Scale and National Assessment System of Science-Related Affective Domain (Kim et al., 1998). Based on the results, authors judged that the Science Academic Emotion Scale for Elementary Students achieved an acceptable validity and reliability.

• Journal of Families and Better Life
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• v.20 no.3
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• pp.139-156
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• 2002

The purpose of this study is to compare the patterns of time use between Korean and USA families. The data for 353 Seoul-based Korean families with two children living in Seoul and 130 USA families with two children living in the State of Utah were collected using a structured questionnaire and time diary. The major findings were as the following: 1. The Korean couples spent more time at personal care, paid work, and travel than the USA couples did, while the USA couples spent more time at housework and social-cultural activities than the Korean couples did. 2. The Korean wives spent more time doing food and clothing related housework than the USA wives did. Compared with the Korean wives, however, the time spent at house cleaning and management, family care and shopping and home management were longer than USA wives. The time U.S. husbands engaged in housework was much greater than by the Korean husbands. 3. Regardless of sex and school level, the Korean children spent less time at sleeping/rest, housework and socio-cultural activities and more time at eating and learning than those of U.S. These time use patterns of the families in both countries may reflect the differences of the cultural contexts, social norms, life styles, and the degrees of urbanization. To fully explain the findings, further study on the differences in social and cultural factors between the two countries is needed.

• Korean Journal of Human Ecology
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• v.16 no.4
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• pp.699-710
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• 2007

The study purposes to explore the effects of individual characteristics and home environments of children on their bilingual language aquisition, that is, to examine whether their English language competency is different from their Korean language competency depending on those variables. Thus English or Korean language competency of children who had had early exposure in English learning were studied in terms of child's individual characteristics such as age, gender, exposure period to English, intelligence, and experiences of visiting English-speaking countries, and home environments such as parental age, educational level, income level, their perceived English competency, their perceived significance of English and Korean language, and the frequency of using English at home. 72 children who went to English kindergarten were tested with Peabody Pictures Vocabulary Test-Revised (PPVT-R) in Korean version and in English version respectively. The results show that child's intelligence and experiences of visiting English-speaking countries influence their Korean language competency. Also child's age, exposure period to English and experiences of visiting English-speaking countries influence their English language competency. Moreover their mother's educational background, father's English fluency, mothers' English fluency, and the frequency of using English at home influence child's English language competency, whereas any variables did not influence child's Korean language competency. Accordingly, child's English and Korean language competencies are related to each other.

• International Journal of Contents
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• v.10 no.4
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• pp.53-62
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• 2014

Although many studies have considered the outcomes and impacts of serious games, little is known about the factors which affect a user's perception or interpretation in games during the process of decision making from theoretical perspectives. This study aimed to explore the process of user perception from the perspective of construal level theory, and to suggest a theoretical design approach for the development of effective serious games. In the current study, cognitive and affective learning outcomes were articulated through literature review and synthesized into a series of assumptions with persuasive and educational aspects in serious games. Serious games reflect the potential of the game mechanism for changing players' perception, and helping with knowledge acquisition of the users. The potential to use construal level theory for effective serious games interventions was suggested, and a Serious Games Design Framework was proposed via potential outcomes from recent advanced research. Finally, implications of the application of the suggested model with various-related purposes and directions for future research were discussed. The model could be useful not only for game researchers and designers, but also for game marketers in attracting potential consumers.