• Journal of the Korean Electrochemical Society
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• v.22 no.1
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• pp.22-35
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• 2019

Development of low cost rechargeable batteries has been considered as a significant task for future large-scale energy storage units (i.e. electric vehicles, smart grids). Sodium-ion batteries (SIBs) have been recognized as a promising alternative to replace conventional lithium-ion batteries (LIBs) because of their abundancy and economic benign. Nevertheless, Na ions have larger ionic radius than that of Li ions, resulting in sluggish transport of Na ions in electrodes for cell operation. There have been efforts to seek suitable anode materials for the past years operated based on three different kinds of reaction mechanism (intercalation, alloy reaction, and conversion reaction). In this review, we introduce a class of conversion reaction anode materials for Na-ion batteries, which have been reported.

• Convergence Security Journal
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• v.18 no.2
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• pp.49-58
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• 2018

As the demand for Internet of Things(IoT) increases, the need for the security of IoT devices is increasing steadily. It is difficult to apply the conventional security theory to IoT devices because IoT devices are subject to be constrained by some factors such as hardware, processor, and energy. Nowadays we have several security guidelines and related documents on IoT device. Most of them, however, do not consider the characteristics of specific IoT devices. Since they describes the security issues comprehensively, it is not easy to explain the specific security level reflecting each characteristics of IoT devices. In addition, most existing guidelines and related documents are described in view of developers and service proposers, and thus ordinary users are not able to assess whether a specific IoT device can protect their information securely or not. We propose an security evaluation model, based on the existing guidelines and related documents, for more specific IoT devices and prove that this approach is more convenient to ordinary users by creating checklists for the smart watch.

• Food Science and Industry
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• v.53 no.3
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• pp.284-294
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• 2020

High voltage pulsed electric field technology has been attracting attention in the the food industry as an eco-friendly nonthermal process technology using electrical energy. The lack of understanding of the equipment and the burden of equipment cost have not significantly increased the commercial application, but the potential as a technology to replace the heat process has been continuously increased. Sterilization of foods using the PEF process has been applied to liquid foods with low viscosity such as fruit and vegetable juices, but recently, high viscosity smoothies, high concentrate protein drink, mixed juice, and alcoholic beverages. Studies on sterilization of solid foods such as powders, raw meats are also being conducted. Also, the application of extraction and recovery of useful ingredients, activation of active compounds, pretreatment of drying, improvement of meat quality, changes of properties of starch has been studies.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.21-28
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• 2021

In this study, we propose a deep learning-based NILM technique using actual measured power data for 5 kinds of home appliances and verify its effectiveness. For about 3 weeks, the active power of the central power measuring device and five kinds of home appliances (refrigerator, induction, TV, washing machine, air cleaner) was individually measured. The preprocessing method of the measured data was introduced, and characteristics of each household appliance were analyzed through spectogram analysis. The characteristics of each household appliance are organized into a learning data set. All the power data measured by the central power measuring device and 5 kinds of home appliances were time-series mapping, and training was performed using a LSTM neural network, which is excellent for time series data prediction. An algorithm that can disaggregate five types of energies using only the power data of the main central power measuring device is proposed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.9
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• pp.1158-1164
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• 2020

In Korea, the dependence on imported energy is very high, and research to reduce standby power is being conducted based on Zigbee, a low-power technology, to reduce wasted power and improve power efficiency. However, because Zigbee is not an IoT standard protocol and is not network-based, it is necessary to build a network with a separate gateway, and research on standby power is insufficient because the standards for international power consumption of devices are ambiguous. Therefore, in this paper, we applied the IoT standard protocol MQTT to the existing Zigbee technology to build a network network without a separate gateway, and designed and implemented a standby power reduction system that collects standby power degradation and user patterns. As a result of evaluating with the existing system, it was confirmed that about 7.11% of standby power was consumed compared to the existing system.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.32 no.2
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• pp.5-24
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• 2021

This study intended to look at the Library Living Lab to solve community problems. To this end, this study investigated cases outside of the country and investigated various aspects of Living Lab's application to solving community problems. In addition, a survey was conducted on residents of Chungju to find areas where libraries can contribute to solving problems in the community and investigate the need. As a result, residents generally responded that "Library Living Lab," in which libraries participate in living lab activities in various fields, is needed to solve problems in the community. It shows that the range of services and activities that the library can provide can be expanded to the community and can be an innovative measure for library services that can solve almost all problems in the community through the Library Living Lab.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.3
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• pp.281-291
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• 2022

Global warming is accelerating due to the use of fossil fuels that have been used continuously for centuries. Now, humankind recognizes its seriousness, and is conducting research on searching for eco-friendly and sustainable energy. In the field of solar energy, which is a kind of eco-friendly and sustainable, many studies are being conducted to enhance the output performance of the module. In this study, the output improvement for the shingled module structure was studied. In order to improve the output performance of the module, the thickness of the encapsulant was increased, and the lamination process conditions have been improved accordingly. After that, the crosslinking rate was analyzed, and the suitability of the lamination process conditions was judged using this. In addition, a peeling test was conducted to analyze the correlation between the adhesion of the encapsulant and the output performance of the module. Finally, the optimization for the encapsulant material and the lamination process conditions for high-power shingled modules was established, and accordingly, the market share of high-power shingled modules in the solar module market can be expected to rise.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.1
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• pp.17-33
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• 2022

Ti₃C₂T_X MXene, first reported by Naguib et al. in 2011, has attracted tremendous attention due to its excellent hydrophilicity, electrical conductivity, and mechanical/chemical stability. Since MXene is a two-dimensional material with a thickness of few nanometers, which ensure its flexibility. In last few years, due to these properties many researchers used Ti₃C₂T_X MXene into various fields such as flexible smart sensors, energy harvesting/storage devices, supercapacitors and electromagnetic interference shielding systems. In this review article, we have briefly discussed the various synthesis processes and characteristics of Ti₃C₂T_X MXene. Moreover, we reviewed the latest development of Ti₃C₂T_X MXene as flexible electrode material to be used into different applications.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.4
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• pp.164-170
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• 2021

Research was conducted to analyze and improve the kinetic performance of offshore wind power generators. The shape used in this study was taken with reference to the previous paper, and the size of the repair area was designed at 80%, 60%, 40%, and 20%, respectively, and the exercise performance was confirmed accordingly. The sea state was calculated in Sea State 4, 5, and 6. In the calculation process, the calculation was performed using commercial computational hydrodynamics (ANSYS) and AQUA. In the case of overall exercise performance, it was confirmed that the smaller the size of the repair area, the smaller the exercise such as heave, roll, and pitch. However, it was confirmed that in the case of a shape in which the size of the repair area was rapidly reduced, there may be cases in which the restoration performance was not satisfied when the restoration calculation was performed. In addition, it was confirmed that there may be an appropriate repair surface depending on the sea condition.

• Journal of the Korea Convergence Society
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• v.12 no.7
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• pp.159-167
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• 2021

The increasingly severe environmental problems such as resource depletion and ecological damage, and consumers' concern for sustainable fashion, make the fashion industry chain develop towards green energy saving. The purpose of this study is to explore the attitude and consumption psychology of specific groups towards sustainable fashion consumption, as well as their specific views and attitudes towards recycled textiles or fabrics for re-manufacturing clothing. This paper attempts to understand how the characteristics of recycled clothing affect consumer. Based on the review of relevant literature, a series of determinants affecting consumer behavior is determined, and the characteristics of recycled products, such as expression value and social value, are determined. An online questionnaire was designed based on this conceptual framework, and 226 valid, complete answers were received. The results show that the emphasis on social value and environmental protection consciousness can effectively affect consumers' decision-making. These findings were helpful to the research of whole green environmental protection and ecological clothing recycling industry system, promote the sustainable development of the clothing industry.