• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.1
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• pp.37-41
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• 2016

Localization is one of the key issues of demandable applications, especially smart services. Beside the traditional GPS based localization technique, the localization issue by visible light communications is promising market because of possibility of combining visible light communications with positioning technique for a high accurate, especially indoor localization service. This paper provides the overview and new image sensor scheme for localization issue based on visible light communication. The survey is introduced from core techniques to enhancement issues of localization. We hope these will be the essential references for the impact selection method in implementation and standardization issues.

• Journal of Power Electronics
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• v.12 no.5
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• pp.842-850
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• 2012

Learning Power Electronics is essential in both electrical and electronic engineering fields and the introductory courses are similar in many universities. Taking this premise into account, an educational computer-aided platform for power electronics will be presented in this paper. This educational platform includes an e-book, a set of power electronics animations, Java simulations, as well as several hands-on training sessions. The main advantages of this platform are twofold. First, all necessary teaching tools are combined on a single platform. And secondly, access to this platform is available free of charge and with no complicated registration requirements. In addition to traditional teaching techniques, the use of this platform has demonstrated an increase in student participation and has consistently improved their academic performance. Data consist of surveys, which guarantee both reliability and validity through psychometric techniques.

• Proceedings of the KSR Conference
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• 2009.05b
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• pp.623-628
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• 2009

There is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. Many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation(PWM) converter. Especially, the phase shift full bridge zero voltage switching PWM techniques are thought most desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.321-324
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• 2008

Recently, there is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation(PWM) converter. Among them, the phase shift full bridge zero voltage switching PWM techniques are thought most desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

• Journal of Magnetics
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• v.18 no.3
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• pp.361-364
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• 2013

Permanent magnet flux switching motor (PMFSM) is a novel double salient machine which employs PMs instead of field winding for excitation. PMFSM contains only one set of armature winding, thereby features simple control strategy, low cost power inverter and substantial high efficiency. Due to the unique double salient structure and operation principle, the generated cogging torque in PMFSM is critical and quite different compared to the traditional PM machines. This paper presents and investigates various design techniques for reducing cogging torque in PMFSM. Firstly, an analytical model is proposed to study the influence of different methods on cogging torque. Then the optimal design parameters for minimizing cogging torque are determined by the analytical model, which significantly reduces the computational efforts. At last, the cogging torque with different design approaches are simulated by FEA along with the average output electromagnetic torque, which validates the analysis above.

• IEMEK Journal of Embedded Systems and Applications
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• v.6 no.4
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• pp.201-207
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• 2011

This paper introduces a novel concept of 'Emotional Communication' for future smart phone. While traditional information based communication technologies focus on how to precisely transmit the content of message, emotional communication is intended to support and augment social relationship among people and to comfort the user to be happy. In this paper, we propose future communication services and core technologies which can estimate emotional desire of users and respond to the desire to be happy with connectedness and consolation from peoples. Firstly, we introduce emotion recognition techniques to estimate emotional desire of users. At second, the emotional responding services are categorized to four parts and the details are shown. Lastly we propose the process to implement emotional communication system and the main techniques to fulfill the system requirements for future smart-phone services.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.155-162
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• 2021

The expansion of the world wide web has led to a huge amount of user generated content over different forums and social media platforms, these rich data resources offer the opportunity to reflect, and track changing public sentiments and help to develop proactive reactions strategies for decision and policy makers. Analysis of public emotions and opinions towards events and sentimental trends can help to address unforeseen areas of public concerns. The need of developing systems to analyze these sentiments and the topics behind them has emerged tremendously. While most existing works reported in the literature have been carried out in English, this paper, in contrast, aims to review recent research works in Arabic language in the field of thematic sentiment analysis and which techniques they have utilized to accomplish this task. The findings show that the prevailing techniques in Arabic topic-based sentiment analysis are based on traditional approaches and machine learning methods. In addition, it has been found that considerably limited recent studies have utilized deep learning approaches to build high performance models.

• Journal of Korean Foot and Ankle Society
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• v.22 no.3
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• pp.83-90
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• 2018

Chronic lateral ankle instability occurs in 10% to 20% of individuals after acute ankle sprain. The management of chronic lateral ankle instability is traditionally conservative treatment in the acute phase. On the other hand, surgical intervention is considered if conservative treatment fails and the symptoms are ongoing. This review focuses on the surgical approaches to treatment of chronic lateral ankle instability, including $Brostr{\ddot{o}}m$ surgical techniques, with a review of the traditional procedure and newer techniques.

• Computers and Concrete
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• v.24 no.3
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• pp.271-282
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• 2019

Concrete undergoes a series of thermo-based physio-chemical changes once exposed to elevated temperatures. Such changes adversely alter the composition of concrete and oftentimes lead to fire-induced explosive spalling. Spalling is a multidimensional, complex and most of all sophisticated phenomenon with the potential to cause significant damage to fire-exposed concrete structures. Despite past and recent research efforts, we continue to be short of a systematic methodology that is able of accurately assessing the tendency of concrete to spall under fire conditions. In order to bridge this knowledge gap, this study explores integrating novel artificial intelligence (AI) techniques; namely, artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS) and genetic algorithm (GA), together with traditional statistical analysis (multilinear regression (MLR)), to arrive at state-of-the-art procedures to predict occurrence of fire-induced spalling. Through a comprehensive datadriven examination of actual fire tests, this study demonstrates that AI techniques provide attractive tools capable of predicting fire-induced spalling phenomenon with high precision.

• Electronics and Telecommunications Trends
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• v.36 no.5
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• pp.82-91
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• 2021

This study reviews application of data-driven anomaly detection techniques to the aviation domain. Recent advances in deep learning have inspired significant anomaly detection research, and numerous methods have been proposed. However, some of these advances have not yet been explored in aviation systems. After briefly introducing aviation safety issues, data-driven anomaly detection models are introduced. Along with traditional statistical and well-established machine learning models, the state-of-the-art deep learning models for anomaly detection are reviewed. In particular, the pros and cons of hybrid techniques that incorporate an existing model and a deep model are reviewed. The characteristics and applications of deep learning models are described, and the possibility of applying deep learning methods in the aviation field is discussed.