• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.209-213
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• 2019

Recently, demand for high energy density and long cycling stability of energy storage system has increased for application using with frequency regulation (F/R) in power grid. Supercapacitor have long lifetime and high charge and discharge rate, it is very adaptable to apply a frequency regulation in power grid. Supercapacitor can complement batteries to reduce the size and installation of batteries. Because their utilization in a system can potentially eliminate the need for short-term frequent replacement as required by batteries, hence, saving the resources invested in the upkeep of the whole system or extension of lifecycle of batteries in the long run of power grid. However, low energy density in supercapacitor is critical weakness to utilization for huge energy storage system of power grid. So, it is still far from being able to replace batteries and struggle in meeting the demand for a high energy density. But, today, LIC (Lithium Ion Capacitor) considered as an attractive structure to improve energy density much more than EDLC (Electric double layer capacitor) because LIC has high voltage range up to 3.8 V. But, many aspects of the electrochemical performance of LIC still need to be examined closely in order to apply for commercial use. In this study, in order to improve the capacitance of LIC related with energy density, we designed new method of pre-doping in anode electrode. The electrode in cathode were fabricated in dry room which has a relative humidity under 0.1% and constant electrode thickness over $100{\mu}m$ was manufactured for stable mechanical strength and anode doping. To minimize of contact resistance, fabricated electrode was conducted hot compression process from room temperature to $65^{\circ}C$. We designed various pre-doping method for LIC structure and analyzing the doping mechanism issues. Finally, we suggest new pre-doping method to improve the capacitance and electrochemical stability for LIC.

• The Journal of Korean Philosophical History
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• no.28
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• pp.35-60
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• 2010

In this paper, the researcher investigated the relationships between nature and humans through I-Ching(『周易』) from the perspective of environmental ethics. I-Ching(『周易』) is a literature which has been quoted so frequently as a desirable alternative for environmental issue. The researcher closely reviewed how the relationships between nature and humans had been defined in I-Ching(『周易』) and developed the discussions focusing on what humans could and should do for nature. Nature makes up for the portion of extinction through endless birth. By giving birth for a new life continuously, and complementing the portion of extinction at the same time, nature is being maintained and preserved. In the side of nature, extinction and birth are equal, meanwhile, the sage who wrote I-Ching(『周易』) had held the concept of anxiety worrying that the whole living beings would be extinct, therefore, the sage wrote I-Ching(『周易』) in the aspects of birth. For nature has always been maintained and preserved in its own cause, there is no chance of nature being destroyed by itself. Human is one living being amongst all things created by nature, and at the same time, humans had been endowed with a position which is one among SanCai(三才). Nature had given humans responsibility and duty according to their position, but humans neglect to perform their responsibility and duty indulging in enjoyment of their position. Because humans have only enjoyed their position which is the critical one amongst SanCai (三才), this failure has resulted in destruction of nature. It shall be necessary for humans to enjoy their position to a certain extent, in the meantime, however, they should discharge those responsibilities and duties in order for forming and nourishing powers of Heaven and Earth. Although it is the humans that have destroyed nature, they can also provide nature with help to give birth to a new life. Reason for humans have destroyed nature is that they forgot their responsibility and duty having been concealed by their selfish desires. If humans get rid of their selfish desires, and fulfill their given duties and responsibilities, nature shall become revitalized again.