• ETRI Journal
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• v.41 no.3
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• pp.298-307
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• 2019

This paper investigates the use of the inverse-free sparse Bayesian learning (SBL) approach for peak-to-average power ratio (PAPR) reduction in orthogonal frequency-division multiplexing (OFDM)-based multiuser massive multiple-input multiple-output (MIMO) systems. The Bayesian inference method employs a truncated Gaussian mixture prior for the sought-after low-PAPR signal. To learn the prior signal, associated hyperparameters and underlying statistical parameters, we use the variational expectation-maximization (EM) iterative algorithm. The matrix inversion involved in the expectation step (E-step) is averted by invoking a relaxed evidence lower bound (relaxed-ELBO). The resulting inverse-free SBL algorithm has a much lower complexity than the standard SBL algorithm. Numerical experiments confirm the substantial improvement over existing methods in terms of PAPR reduction for different MIMO configurations.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1834-1847
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• 2016

Main objectives of the this study are: to develop a model of "Flipped Leaning" that is designed to enhance self-directed learning, learning motivation and self-control, and to verify its effectiveness-in higher education. The verification process initially concentrated on the feasibility study of the model with a thorough literature review and case analyses; then, its general and practical applicability were tested with a field study. As a result, first, the CHANGE Class Model, specifically designed for effective and efficient "Flipped Learning", was developed. It is thus named for the stages that the learning process takes place in the model-i.e., (1) Check ${\rightarrow}$ (2) Ask ${\rightarrow}$ (3) Notice ${\rightarrow}$ (4) Group presentation ${\rightarrow}$ (5) Evaluation, and it emphasizes the dynamic, questions centered (i.e. back and forth between the students and the instructor as well as between the students) learning process. Second, the Model was instrumental in enhancing self-directed learning, learning motivation and self-control; thus, as a result, it significantly improved the effectiveness, the level of concentration and the attractiveness of the learning process. The value of this study lies in pointing to a clear plan to allow a student in higher learning to set-up a self-directed learning plan, to be able to control it while being continuously motivated to complete it.

• The Journal of Korean Academic Society of Nursing Education
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• v.20 no.2
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• pp.341-349
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• 2014

Purpose: This study was conducted to compare blended practicum with clinical and lab combined e-learning between cooperative and individual group on learning outcomes. Method: A total of 63 junior Nursing students were recruited from C University in G city from May, 2012 to June, 2012. Ten hours lab practicum for two weeks was provided for both two groups during the period of adult nursing practicum. Prior to blended practicum, e-learning was conducted. For cooperative group, two hours off line team learning with a tutor for eight weeks was provided, in other hands, for individual group, any off line team learning was not provided and self study on line was not evaluated by the tutor. Results: The result of ANCOVA showed that critical thinking and self directed learning were significantly improved in the individual group compared to the cooperative group (F=-18.15, p<.001; F=28.12, p<.001). In other hands, clinical competence was significantly higher in the cooperative group than in the individual group (F=16.61, p<.001). Conclusion: Through development of self-leaning facilitating online contents, the blended practicum combined e-learning could be effective in critical thinking, self-directed learning and clinical competence. Further studies about e-learning strategies of off-line learning are still needed.

• Journal of Internet Computing and Services
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• v.9 no.6
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• pp.141-153
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• 2008

E-learning is a new paradigm of education using Internet media. E-learning is rapidly expanding, since it is not restricted by time and space. However, due to the lack of standardization in e-learning, learning contents are developed redundantly. SCORM has been proposed to address this standardization problems. The mere learning contents are shared, the higher the reusability of contents becomes. Therefore, it is needed to develop methods or tools to help educators or content producers to create a learning course easily. In this paper, we propose an association method that could help educators or content producers to efficiently generate learning courses for a subject. The association method, a learning course generation method suggested by this paper, makes use of existing learning courses and learning contents to create new learning courses suitable to a subject. The association method analyzes statistical information of leaning objects derived from existing learning courses and measures coherence between learning objects to create a learning course. The association method suggested by this paper not only supports educators or content producers for easy generation of learning course but also offers a guideline for developing learning courses.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.25-31
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• 2008

It is important for users to be confirming in e-Leaning system, because legitimate learner should be joined to the system for teaming and testing Thus, most system for authentication was verified using id and password with learner's id and password. In this case, It can be easy for hackers to steal learner's id and password. In addition, soma learner gets another to sit for the examination for one with another person id and password. For the solution like this problem it needs a biometrics authentication for complement. This method is required so much extra cost as well as are an unwanted concern. Therefore, we proposed keystroke technique to decide which learners are righteous or unlawful in this paper. In addition, we applied statistics and neural network for the performance of keystroke system. As a result, the performance of FAR and FRR in keystroke authentication was increased by proposed method.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.10a
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• pp.37-43
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• 2001

New product development has been a key element fur organizational evolution. The bulk of research about new product strategy has focused solely on new product development function itself. This paper investigates cross-functional elements in new product development. More specifically, we suggest that there must exist a fit between new product strategy and value chain strategy. It means that, in order to support new product development activity, there must exist a relevant value chain strategy. We consider three types of integration - internal integration, customer integration, and supplier integration - as strategic elements of value chain strategy. For the case of new product strategy, we consider market newness and product technology unfamiliarity as strategic elements. We also consider two types of learning characteristic, i.e., \\\"fast-adaptive learning\\\" and \\\"slow-adaptive leaning\\\" as control factor. Learning characteristic represents firms organizational capability related with organizational learning. For example, fur fast-adaptive learning case, the effect of integration appears early in time. System dynamics simulation is employed to verify our research framework. The results exhibit that there must exist cross-functional relationships between value chain strategy and new product strategy in order to shorten total development time.al development time.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.477-485
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• 2010

Web based learning systems are operating with various and lots of learning contents. But it is hard to construct learning contents to fit learners when they select learning contents for learning. In this paper, we proposed the recommendation method that can support the learning contents as calculate learner's preference using the learning history information of learner's profile when learner design and compose learning course. In the applying result of this method, we've selected testing learner group and was able to know it can help to learner processing learning by themselves as we've got great learning satisfaction after test.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.4
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• pp.523-542
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• 2009

The purpose of this study was to figure out the procedure of learning Korean for international students. A research question was set up as follows: What is the procedure of leaning Korean for international students in Korean universities? To achieve the research purpose, this study implemented a method of semi-constructed interviews. Nineteen international students participated in the interview. The collected data for this study included transcripts from each interview. The transcripts of 60 minutes of interviews with all the participants was audio-taped recorded. This study investigated the research question based on the grounded theory. The analysis of open coding, axial-coding, and selective coding was used in the study. Results indicated that international students learned Korean in a daily basis, and then they adapted to academic Korean in their majored fields. Both personality and mother tongue influenced Korean language learning positively and negatively. International students' improvement of Korean was related in studying with Korean mass media such as TV soap dramas, talk shows, and songs. International students think that TOPIK(Test Of Proficiency In Korean) is not much related with their Korean language fluency. In conclusion, the researchers suggested to give more emphasis on academic training courses for Korean language and to improve the TOPIK in general academic Korean.

• Journal of The Korean Association of Information Education
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• v.16 no.4
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• pp.439-450
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• 2012

This paper explores effectiveness of integrating Problem-Based Learning with Web 2.0 technologies in Computer subject matter education for improving quality of lessons and adapting of social needs for pre-service teachers. Students have studied about computer subject matter for 4 times. The process of leaning have recorded by Web 2.0 tools that is one of the cloud services. Also the students have written reflection journals about experiences of PBL process and results. The PBL process and reflection journals have been analyzed by qualitative data analysis. Conclusions are drawn as to potential for the use of Web 2.0 tools for PBL in computer subject matter. The results of the analyses showed the following: 1) Increasing the understanding of the computer subject matter education, 2) enhancing students' competence in using ICT potentially, 3) cultivating teaching and learning strategies on Web 2.0 environment and 4) enhancing competence of future teaching activities through experiencing e-portfolio as a performance-assessment tool.

• The Journal of Society for e-Business Studies
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• v.25 no.1
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• pp.1-12
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• 2020

Recently, research using machine learning have shown remarkable results in various domains, leading to the fact that leaning-based dispatchers have intrigued interest in both academia and industry. To improve the performance of the dispatcher, each dispatch decision needs to be evaluated in detail. However, existing studies on visualization techniques for manufacturing lines have mainly focused on illustrating the performance indicators or abnormal patterns. In this paper, we propose a monitoring system that displays a variety of information about the manufacturing line along with alternatives at the time of each dispatching decision being made. Furthermore, the proposed system effectively represents the cause of the idle time of resources and the change of the performance index over time.