• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.2
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• pp.383-388
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• 2024

This paper is a study to derive the predicted value of power generation based on the photovoltaic power generation data measured in Jeollanam-do, South Korea. Multivariate variables such as direct current, alternating current, and environmental data were measured in the inverter to measure the amount of power generation, and pre-processing was performed to ensure the stability and reliability of the measured values. Correlation analysis used only data with high correlation with power generation in time series data for prediction using partial autocorrelation function (PACF). Deep learning models were used to measure the amount of power generation to predict the amount of photovoltaic power generation, and the results of correlation analysis of each multivariate variable were used to increase the prediction accuracy. Learning using refined data was more stable than when existing data were used as it was, and the solar power generation prediction algorithm was improved by using only highly correlated variables among multivariate variables by reflecting the correlation analysis results.

• Journal of The Korean Association For Science Education
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• v.28 no.8
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• pp.779-785
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• 2008

In this study, we investigated the role of a discrepant event from both cognitive and motivational perspectives in learning the concept of combustion. A preconception test, a test of response to a discrepant event, and a situational interest questionnaire were administered to 433 eighth graders. After learning the concept of combustion, the tests of attention, effort, and conceptual understanding were administered as post-tests. The reponses of 208 students who had been found to possess the target misconception were analyzed. The percentages of rejection and exclusion responses were relatively high compared to the previous studies about density concept, whereas a proportion of belief change was low. The results of the path analysis indicated that situational interest after presenting an alternative hypothesis had a direct effect and an indirect effect via attention and effort on conceptual understanding. Situational interest induced by a discrepant event directly influenced cognitive conflict after presenting an alternative hypothesis.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.179-192
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• 2014

Keeping in line with the recent changes in the information technology environment, the online learning environment that supports multiple users' participation such as MOOC (Massive Open Online Courses) has become important. One of the largest professional associations in Information Technology, IEEE Computer Society, announced that "Supporting New Learning Styles" is a crucial trend in 2014. Popular MOOC services, CourseRa and edX, have continued to build active learning environment with a large number of lectures accessible anywhere using smart devices, and have been used by an increasing number of users. In addition, collaborative web services (e.g., blogs and Wikipedia) also support the creation of various user-uploaded learning materials, resulting in a vast amount of new lectures and learning materials being created every day in the online space. However, it is difficult for an online educational system to keep a learner' motivation as learning occurs remotely, with limited capability to share knowledge among the learners. Thus, it is essential to understand which materials are needed for each learner and how to motivate learners to actively participate in online learning system. To overcome these issues, leveraging the constructivism theory and collective intelligence, we have developed a social bookmarking system called WeStudy, which supports learning material sharing among the users and provides personalized learning material recommendations. Constructivism theory argues that knowledge is being constructed while learners interact with the world. Collective intelligence can be separated into two types: (1) collaborative collective intelligence, which can be built on the basis of direct collaboration among the participants (e.g., Wikipedia), and (2) integrative collective intelligence, which produces new forms of knowledge by combining independent and distributed information through highly advanced technologies and algorithms (e.g., Google PageRank, Recommender systems). Recommender system, one of the examples of integrative collective intelligence, is to utilize online activities of the users and recommend what users may be interested in. Our system included both collaborative collective intelligence functions and integrative collective intelligence functions. We analyzed well-known Web services based on collective intelligence such as Wikipedia, Slideshare, and Videolectures to identify main design factors that support collective intelligence. Based on this analysis, in addition to sharing online resources through social bookmarking, we selected three essential functions for our system: 1) multimodal visualization of learning materials through two forms (e.g., list and graph), 2) personalized recommendation of learning materials, and 3) explicit designation of learners of their interest. After developing web-based WeStudy system, we conducted usability testing through the heuristic evaluation method that included seven heuristic indices: features and functionality, cognitive page, navigation, search and filtering, control and feedback, forms, context and text. We recruited 10 experts who majored in Human Computer Interaction and worked in the same field, and requested both quantitative and qualitative evaluation of the system. The evaluation results show that, relative to the other functions evaluated, the list/graph page produced higher scores on all indices except for contexts & text. In case of contexts & text, learning material page produced the best score, compared with the other functions. In general, the explicit designation of learners of their interests, one of the distinctive functions, received lower scores on all usability indices because of its unfamiliar functionality to the users. In summary, the evaluation results show that our system has achieved high usability with good performance with some minor issues, which need to be fully addressed before the public release of the system to large-scale users. The study findings provide practical guidelines for the design and development of various systems that utilize collective intelligence.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.3
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• pp.201-214
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• 2022

This study theoretically and empirically examined whether organizational communication mediates the effect of organizational learning culture perceived by members in the organization on task performance and contextual performance. Organizational learning culture is defined as a culture that is good at creating, acquiring, transferring, and modifying behavior to reflect new knowledge and insights. The hypothesis of this study is that the perceived organizational learning culture can increase performance through organizational communication between members. In particular, we measured communication within the organization into three types: upward, horizontal, and downward. These communications were set as mediating variables. In empirical studies, independent variables were perceived organizational learning culture, mediation variables were upward, horizontal and downward communication, and dependent variables were task performance and contextual performance. Hypothesis 1 is that the organizational learning culture will have a positive effect on employees' tasks and contextual performance. Hypothesis 2 is about the mediating effect of communication on the relationship between Hypothesis 1. In the empirical study, after verifying the validity and reliability of the research variables, correlation analysis and hypothesis verification were conducted. Hypothesis 1 was verified through regression analysis, and all detailed hypotheses were supported. To verify Hypothesis 2, we conducted a bootstrap test using process macro to separate the total, direct, and indirect effects and examine the significance of the indirect effects. As a result, Hypothesis 2 was partially supported. Downward communication mediated organizational learning culture and task and contextual performance, and horizontal communication mediated organizational learning culture and contextual performance. The mediating effect of upward communication was not significant. The results of this study contributed to the suggestion of implications, research limitations, and research directions. Organizational learning culture is the direction and intention of the organization to achieve its goals through the learning and growth of its members. By strengthening internal motivation, organizational members can take voluntary desirable actions that help groups and organizations as well as essential tasks given. since this relationship appears as a medium of downward communication, organizations can strengthen the relationship between organizational learning culture and performance through leadership education.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.292-310
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• 2021

The influence of COVID 19 has a direct impact on the education field. In the situation where non-face-to-face classes are inevitably required, interest in the learning satisfaction and intention to use real-time video conferencing is increasing. This study analyzed the effects of learner-teacher interaction, social presence, availability, self-efficacy and academic engagement as video conferencing characteristics and learner's characteristics on perceived usefulness, perceived ease of use, learning satisfaction and intention to use video conferencing. The results of this study showed that learner-teacher interaction, availability, and self-efficacy had a positive effect on perceived ease of use, and all variables except availability had a positive effect on perceived usefulness. Also, perceived usefulness and ease of use were factors that increased learning satisfaction and video conferencing use intention, and learning satisfaction was identified as variables that increased video conferencing use intention. This study has significance in that it provided various theoretical and practical implications for real-time video conferencing which will be used in many educational fields in the future through empirical analysis.

• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.379-402
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• 2022

The purpose of this study was to verify the effectiveness of the employee metacognition and it's positive effect on employee agility. Also it aims to investigate the mechanism through the cascading multi-mediating effect through the role breadth self-efficacy and learning agility in such a relationship. In order to solve the common-method bias, independent and dependent variables were measured with time lag, and the relationship between variables was clearly verified by applying the position and the length of time worked with the supervisor as control variables. In testing the hypothesis, 478 questionnaires collected from whom worked at the company has more than 300 office workers in various industries were analyzed. As the result, firstly metacognition had a significant positive(+) effect on employee agility. Second, role breadth self-efficacy was found to positively mediate the relationship between metacognition and employee agility. Third, learning agility was found to mediate metacognition and employee agility positively(+). Fourth, metacognition serially mediates role breadth self-efficacy and learning agility, and the positive(+) effect on employee agility was verified. In addition, metacognition had a greater effect on member agility when passing through role breadth self-efficacy and learning agility rather than the direct effect on employee agility.

• Journal of Korean Elementary Science Education
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• v.41 no.4
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• pp.627-641
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• 2022

This study aims to help elementary school teachers increase their knowledge about the changes in the positions of the sun and moon during the day and the first time the moon observation begins in the Earth and Space section of the Earth and the Moon. The survey questions were grouped into four categories, namely, textbook explanation, inquiry activities, achievement of learning goals, and other opinions. The perception of each question differed according to advanced science majors and teaching careers and experiences of this unit. In addition, understanding the diverse views of the participants using descriptive questions was possible. The study recruited 67 teachers working at an elementary school in Gyeonggi-do. The conclusion is as follows. First, the teachers exhibited similar positive and negative perceptions about the description of the textbook on the changes in the positions of the sun and moon during the day. Second, the study found that majority of teachers used alternative methods when guiding students regarding the change in the positions. This trend was not correlated with the sun and the moon, and the study observed no difference in advanced majors and teaching careers and experience of this unit. Third, the majority of teachers responded that they could achieve their learning goals through this learning. However, many teachers complained of various difficulties in guiding students about the lesson, and the majority alternative methods. The results demonstrated the perception of teachers that students can achieve learning goals through alternative methods without direct observation.

• Journal of Intelligence and Information Systems
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• v.29 no.1
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• pp.233-247
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• 2023

Recently, research on detecting objects in hidden spaces beyond the direct line-of-sight of observers has received attention. Most studies use optical equipment that utilizes the directional of light, but sound that has both diffraction and directional is also suitable for non-line-of-sight(NLOS) research. In this paper, we propose a novel method of detecting objects in non-line-of-sight (NLOS) areas using acoustic signals in the audible frequency range. We developed a deep learning model that extracts information from the NLOS area by inputting only acoustic signals and predicts the properties and location of hidden objects. Additionally, for the training and evaluation of the deep learning model, we collected data by varying the signal transmission and reception location for a total of 11 objects. We show that the deep learning model demonstrates outstanding performance in detecting objects in the NLOS area using acoustic signals. We observed that the performance decreases as the distance between the signal collection location and the reflecting wall, and the performance improves through the combination of signals collected from multiple locations. Finally, we propose the optimal conditions for detecting objects in the NLOS area using acoustic signals.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.397-404
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• 2024

This study aims to investigate the mediating effects of commitment to learning on the relationship between instructor communication and reselection of the same instructor among college students in lifelong education. For this purpose, the investigator conducted a survey with college students in lifelong education attending a two or three year college or a university in Daegu Metropolitan City and Gyeongsangbuk Province and analyzed a final total of 498 questionnaires with the SPSS 22.0 and AMOS 22.0 statistical programs. The findings were as follows: instructors' verbal and non-verbal communication had total significant effects on the path of reselection of the same instructor by college students in lifelong education, but it had no direct significant effects on reselection of the same instructor. Instructors' verbal and non-verbal communication had indirect effects on reselection of the same instructor by college students in lifelong education via commitment to learning. These findings imply that if instructors make use of their verbal and non-verbal communication in lessons for college students in lifelong education according to their characteristics, it will be able to increase their commitment to learning as well as satisfaction with lessons.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.193-215
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• 2016

In recent years, the proliferation of diverse social networking services has led users to use many mediums simultaneously depending on their individual purpose and taste. Besides, while collecting information about particular themes, they usually employ various mediums such as social networking services, Internet news, and blogs. However, in terms of management, each document circulated through diverse mediums is placed in different categories on the basis of each source's policy and standards, hindering any attempt to conduct research on a specific category across different kinds of sources. For example, documents containing content on "Application for a foreign travel" can be classified into "Information Technology," "Travel," or "Life and Culture" according to the peculiar standard of each source. Likewise, with different viewpoints of definition and levels of specification for each source, similar categories can be named and structured differently in accordance with each source. To overcome these limitations, this study proposes a plan for conducting category mapping between different sources with various mediums while maintaining the existing category system of the medium as it is. Specifically, by re-classifying individual documents from the viewpoint of diverse sources and storing the result of such a classification as extra attributes, this study proposes a logical layer by which users can search for a specific document from multiple heterogeneous sources with different category names as if they belong to the same source. Besides, by collecting 6,000 articles of news from two Internet news portals, experiments were conducted to compare accuracy among sources, supervised learning and semi-supervised learning, and homogeneous and heterogeneous learning data. It is particularly interesting that in some categories, classifying accuracy of semi-supervised learning using heterogeneous learning data proved to be higher than that of supervised learning and semi-supervised learning, which used homogeneous learning data. This study has the following significances. First, it proposes a logical plan for establishing a system to integrate and manage all the heterogeneous mediums in different classifying systems while maintaining the existing physical classifying system as it is. This study's results particularly exhibit very different classifying accuracies in accordance with the heterogeneity of learning data; this is expected to spur further studies for enhancing the performance of the proposed methodology through the analysis of characteristics by category. In addition, with an increasing demand for search, collection, and analysis of documents from diverse mediums, the scope of the Internet search is not restricted to one medium. However, since each medium has a different categorical structure and name, it is actually very difficult to search for a specific category insofar as encompassing heterogeneous mediums. The proposed methodology is also significant for presenting a plan that enquires into all the documents regarding the standards of the relevant sites' categorical classification when the users select the desired site, while maintaining the existing site's characteristics and structure as it is. This study's proposed methodology needs to be further complemented in the following aspects. First, though only an indirect comparison and evaluation was made on the performance of this proposed methodology, future studies would need to conduct more direct tests on its accuracy. That is, after re-classifying documents of the object source on the basis of the categorical system of the existing source, the extent to which the classification was accurate needs to be verified through evaluation by actual users. In addition, the accuracy in classification needs to be increased by making the methodology more sophisticated. Furthermore, an understanding is required that the characteristics of some categories that showed a rather higher classifying accuracy of heterogeneous semi-supervised learning than that of supervised learning might assist in obtaining heterogeneous documents from diverse mediums and seeking plans that enhance the accuracy of document classification through its usage.