• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.289-296
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• 2020

In this paper, the effects of the spontaneous combustion inhibitor on the surface of the coal stockpile in the coal yard was investigated by numerical analysis. First, the numerical analysis method of the present study was compared with the results of the previous study by analyzing the case in which the spontaneous combustion inhibitor was not applied, while the effects of spraying the spontaneous combustion inhibitor for the prevention of spontaneous combustion onto various areas and positions was also analyzed. As a result, the larger the application area of the spontaneous combustion inhibitor, then the more effective it is for preventing spontaneous combustion as it blocks the oxygen inflow into the coal stockpile, while, when spraying the spontaneous combustion inhibitor from the bottom of the coal stockpile, then the greater the effect it has on the prevention of spontaneous combustion. In conclusion, it was most effective to spray the spontaneous combustion inhibitor from the bottom of the coal stockpile up to about 30% of the height of the coal stockpile, when considering the economic aspect.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.59-65
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• 2014

Discriminating between two herbal medicines (Panax ginseng and Panax quinquefolius), with similar chemical and physical properties but different therapeutic effects, is a very serious and difficult problem. Differentiation between two processed ginseng genera is even more difficult because the characteristics of their appearance are very similar. An ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS)-based metabolomic technique was applied for the metabolite profiling of 40 processed P. ginseng and processed P. quinquefolius. Currently known biomarkers such as ginsenoside Rf and F11 have been used for the analysis using the UPLC-photodiode array detector. However, this method was not able to fully discriminate between the two processed ginseng genera. Thus, an optimized UPLC-QTOF-based metabolic profiling method was adapted for the analysis and evaluation of two processed ginseng genera. As a result, all known biomarkers were identified by the proposed metabolomics, and additional potential biomarkers were extracted from the huge amounts of global analysis data. Therefore, it is expected that such metabolomics techniques would be widely applied to the ginseng research field.

• Korea Journal of Cosmetic Science
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• v.1 no.1
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• pp.11-18
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• 2019

Caffeine is widely used in cosmetics and hair care products. Although its efficacy in stimulating hair growth has been confirmed in recent studies, its mechanism of action remains unelucidated. The present study aimed to determine the effects of caffeine on hair growth, with a focus on intracellular hair follicle activity. Experiments included in vitro and ex vivo tests, and a clinical study. Caffeine enhanced the cellular activity and potassium channel opening. It also promoted human hair follicle elongation. Immunohistochemical staining showed that the Ki-67 signal was significantly higher in cells treated with caffeine. These efficacies of caffeine were comprehensively demonstrated in clinical results, wherein caffeine-containing shampoo improved hair density after 24 weeks of testing. Collectively, the results of this study demonstrated that caffeine promoted hair growth and inhibited the progression of hair loss by enhancing intracellular activity of hair follicles.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.453-454
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• 2011

With the transmission line the ratio of lightning breakdown the while whole breaking down is occupying a high share with average 72%, is a tendency which increases continuously. In order decreasing the back flashover faults from like this lightning breakdown, it is very important to maintain grounding resistance of tower below target. In this paper, we synthetically analyzed the grounding resistance reduction effect of tower foundation and standard ground connection from construction site, and investigated efficiency for ways to increase the length of counter poise and expand the size of conductivity concrete materials.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.1901-1902
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• 2006

In recent years, it has been a worldwide trend that many power utilities gave their attention to develop and operate their power plants, substation and distribution systems. Following this trend, KEPCO(Korea Electric Power Corporation) has developed many electric automation systems with various communication networks. It has been natural that the automation systems are just focused on to remote devices when they come to be designed. But, we have to shift the focus to the automation system itself. We have developed the Multi-service Optical Transmission System (M-OTS) for electrical power systems. It can be adopt to not only distribution power field but also the transmission power field. The result strongly shows that the system is potentially beneficial in reliability, speed, and expandability. This paper presents some of initial design efforts and results toward a KEPCO's communication system in distribution areas.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.777-780
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• 2005

The bench of cut-slope is necessary to stabilizing. But it is possible to be a weak zone in slope. When a small scale failure is occurred in a bench, it influence a large scale failure of slope. So when it is found out any unstable factor, weathering of rock, a direction of joint in a bench, if the bench is reinforced suitably, the holly failure is prevented in cut-slope

• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.59-64
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• 2020

Scheduling of electric vehicles and optimizing for charging waiting time have been critical. Meanwhile, it is challengeable to exploit the fluctuating data from electric vehicles in real-time. We introduce an optimal routing algorithm and a simulator with electric vehicles obeying the Poisson distribution of the observed information about time, space and energy-demand. Electric vehicle routing is updated in every cycle even it is already set. Also, we suggest an electric vehicle routing algorithm for minimizing total trip time, considering a threshold of the waiting time. Total trip time and charging waiting time are decreased 34.3% and 86.4% respectively, compared to the previous algorithm. It can be applied to the information service of charging stations and utilized as a reservation service.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1163-1164
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• 2007

At present, one of the big characteristics in electric power market in korea is unique seller but in the near future competitions are expected in the market. so additional service for the electric power are expected. Also with development of IT technology, remote inspection for power usage are possible so as consumption pattern analysis. KORAIL is one of the biggest consumer in electric power market so it is necessary to investigate power consumption pattern. This paper presents electric power rate definition program based on billing system database and also basic power rate optimization method. Base on the substation annual power usage DB data, the characteristic of the substation power consumption are investigated and effective electrical billing system are compared each other. Through this program it is verified that we can save more then several hundred million won for a year.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.527-537
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• 2020

Panax ginseng, a medicinal plant, has been used as a blood-nourishing tonic for thousands of years in Asia, including Korea and China. P. ginseng exhibits adaptogen activity that maintains homeostasis by restoring general biological functions and non-specifically enhancing the body's resistance to external stress. Several P. ginseng effects have been reported. Korean Red Ginseng, in particular, has been reported in both basic and clinical studies to possess diverse effects such as enhanced immunity, fatigue relief, memory, blood circulation, and anti-oxidation. Moreover, it also protects against menopausal symptoms, cancer, cardiac diseases, and neurological disorders. The active components found in most Korean Red Ginseng varieties are known to include ginsenosides, polysaccharides, peptides, alkaloids, polyacetylene, and phenolic compounds. In this review, the identity and bioactivity of the non-saponin components of Korean Red Ginseng discovered to date are evaluated and the components are classified into polysaccharide and nitrogen compounds (protein, peptide, amino acid, nucleic acid, and alkaloid), as well as fat-soluble components such as polyacetylene, phenols, essential oils, and phytosterols. The distinct bioactivity of Korean Red Ginseng was found to originate from both saponin and non-saponin components rather than from only one or two specific components. Therefore, it is important to consider saponin and non-saponin elements together.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.2543-2545
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• 2005

It is well known that the orthogonal function is a very useful to estimate an unknown inputs in the linear dynamic systems for its recursive algebraic algorithm. At this aspects, derivative operation(matrix) of orthogonal functions(walsh, block pulse and haar) are introduced and shown how it can useful to design an UIO(unknown inputs observer) design.