• Journal of the Korean Society for Railway
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• v.7 no.4
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• pp.307-311
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• 2004

Arresters are the best protective device on electrical power systems against transient overvoltages generated by lightning and/or switching operation. Nonetheless, arresters are deteriorated by absorption of moisture in the environments of its use, repetition in the protective operation to overvoltages, and some defects at manufacturing. It is therefore important to estimate the electrical characteristic changes of ZnO blocks. In this paper, an accelerated ageing test by a standard lightning impulse current was carried out to extract parameters needed for arrester diagnosis, and leakage current components were measured. Total energy applied to the ZnO blocks at each time is about 1,050[J] in 8/20[${\mu}\textrm{s}$] impulse current. From the experimental results, we proposed electrical parameters and leakage current level to diagnose arrester soundness.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.664-667
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• 1996

The role of protective relaying system is important in the power system stability and reliability. Conventional relaying schemes have had many problems that adaptiveness for delicate variance of objective power systems is poor, and so on. In these days, in order to overcome the weaknesses, the studies to application of artificial intelligent scheme are required. In this paper, as the preceding research for development of intelligent protective relays, we tried to select the most suitable digital filter using comparison of frequency response and performance of wanted frequency component extraction etc.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.515-516
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• 2007

The marine power system is whole one system including power generation and distribution system. This systems have several power generators which are operated according to voyage situation in the vessel. Therefore, IEDs have to re-setting for changed marine power system. This paper is shown application of multi-setting protective IED in the marine power system.

• Animal cells and systems
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• v.11 no.1
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• pp.33-38
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• 2007

Liposome-entrapped atypical Aeromonas hydrophila antigen was prepared to investigate the potential protective efficacy for A. hydrophila infection. Carp (Cyprinus carpio) were immunized orally with liposome-entrapped A. hydrophila antigen. After immunization, significantly more antigen-specific antibodies were detected in serum, intestinal mucus and bile than non-immunized control group. The immunized carp were then challenged by immersion with $1{\times}10^{6}$ cfu/ml of A. hyrdophila for 60 min. Of the eight non-immunized carp, three carp died (62.5% survival), whereas five out of six (83.5%) of the immunized survived. Furthermore, development of skin ulcers was significantly inhibited in carp immunized with liposomes containing A. hydrophila antigen. These results suggest that liposomes containing A. hydrophila antigen have a potential for induction of protective immune responses against atypical A. hydrophila infection and also suggest the possibility of developing a vaccine that may ultimately be used for prevention of fish diseases.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.365-382
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• 2023

A lithium metal anode with high energy density has the potential to revolutionize the field of energy storage systems (ESS) and electric vehicles (EVs) that utilize rechargeable lithium-based batteries. However, the formation of lithium dendrites during cycling reduces the performance of the battery while posing a significant safety risk. In this review, we discuss various strategies for achieving dendrite-free lithium metal anodes, including electrode surface modification, the use of electrolyte additives, and the implementation of protective layers. We analyze the advantages and limitations of each strategy, and provide a critical evaluation of the current state of the art. We also highlight the challenges and opportunities for further research and development in this field. This review aims to provide a comprehensive overview of the different approaches to achieving dendrite-free lithium metal anodes, and to guide future research toward the development of safer and more efficient lithium metal anodes.

• The Research Journal of the Costume Culture
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• v.17 no.5
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• pp.834-848
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• 2009

The purpose of this study is to analyse the research trends and to find a future direction in the area of clothing construction in Korea. The data were included articles on clothing construction published in the five major journals from 2000 through 2008 in Korea. The identified 513 articles were categorized in eight areas: design related clothing construction, study of body types, study of patterns, size of apparel, fitting of clothing, protective clothing and functional clothing, sewing and the others. In the results of examining the percentage of articles on clothing construction among articles published in each journal, the percentage of articles on clothing construction was highest as 21.2% in the Journal of Korean Home Economics and next, 19.3% in the Research Journal of the Costume Culture. As to the percentage of research on clothing construction according to theme, research on protective clothing and functional clothing were largest as 28.2%, and next, research on body types as 18.9%, and research on garment size systems as 10.5%. Research on protective clothing has increased remarkably since 2000, and particularly in 2004 it was so active that it occupied 44.1% of research on clothing construction. Next, with regard to the subjects of research, research with female subjects was more frequent than that with male subjects according to gender, and research with men and women in their twenties was most frequent according to age. These results show somewhat unbalanced tendencies in terms of research subjects.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.54-54
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• 2023

Nypa fruticans Wurmb (N. fruticans) is a plant that belongs to Araceae and N. fruticans is mainly found in tropical mangrove systems. The parts (leaves, stems, and roots) of N. fruticans are traditionally used for asthma, sore throat, and liver disease. N. fruticans contains flavonoids and polyphenols, which are substances that have inhibitory effects on cancer and oxidant. In previous studies, some pharmaceutical effects of N. fruticans on melanogenesis and inflammation have been reported. The present study is conducted to investigate the effect of the ethyl acetate fraction of N. fruticans (ENF) on oxidative DNA damage and UVB-induced DNA damage. DNA damage response (DDR) pathway is important in research on cancer, apoptosis, and so on. DDR pathways are considered a crucial factor affecting the alleviation of cellular damage. ENF could reduce oxidative DNA damage derived from reactive oxygen species by the Fenton reaction. Also, ENF reduced the intensity of intracellular ROS in the live cell image by DCFDA assay. UVB is known to cause skin and cellular damage, then finally contribute to causing the formation of tumors. As for the strategies of reducing DNA damage by UVB, inhibition of p53, H2AX, and Chk2 can be important indexes to protect the human body from DNA damage. As a result of confirming the protective effect of ENF for UVB damage, MMPs significantly decreased, and the expression of apoptosis-related factors tended to decrease. In conclusion, ENF can provide protective effects against double-stranded DNA break (DSB) caused by oxidative DNA damage and UVB-induced DNA damage. These results are considered to be closely related to the protective effect against radicals based on catechin, epicatechin, and isoquercitrin contained in ENF. Based on these results, it is thought that additional mechanism studies for inhibiting cell damage are needed.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.201-206
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• 2004

With the advent of distributed generation, power systems in general are impacted in regards to stability and power quality. Distributed generation has positive impacts on system restoration following a fault, higher reliability, and mitigation of effect due to voltage sag. However, distributed generation also has negative impacts on the decrease of reliability such as changes of protective device setting and mal-operation. Because bulk power systems consist of various sources and loads, it is complicated to analyze power systems that have distributed generation. The types of distributed generation usually are classified as the rotating machinery system and the inverter-based system. In this paper, distributed generation is designed as a synchronous generator, and the distribution system with its distributed generation model is simulated using EMTP. In addition, this paper shows the simulation results according to the types of distributed generation

• Management & Information Systems Review
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• v.36 no.1
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• pp.81-94
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• 2017

In the age of information overload such as Internet of Things(IoT), big data, and cloud computing, Data and informations are collected to processed regardless of the individual's will. The purpose of this paper presents a model related to personal information overlord, information privacy risk, information privacy concern (collection, control, awareness) and personal information privacy protective response. The results of this study is summarized as follows. First, personal information overload significantly affects information privacy risk. Second, personal information overload significantly affects information privacy concern(collection, control, awareness) Third, information privacy risk significantly affects collection and awareness among information privacy concern, but control does not significantly affects. This results shows that users are cognitively aware the information risk through collection and awareness of information. Users can not control information by self, control of information does not affects. Last, information privacy concern(collection and awareness significantly affect information privacy protective response, but information privacy concern (control) does not affect. Personal information users are concerned about information infringement due to excessive personal information, ability to protect private information became strong.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.1
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• pp.46-53
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• 2017

This paper shows a length of wirecutter using an analysis based on Rotorcraft's control input and taxiing speed. In case of selecting an inappropriate length of wirecutter which applies to rotorcraft for safety, this causes a collision between blade and wirecuter, or an accident by wire. We review the control input which was used in development stage, and establish the conditions of control input which are needed in taxiing. Based on these conditions, we review the collision possibility between blade and wirecutter through analysis in case of 20, 40, 60 kts taxiing speed. Following, this result is verified by comparison with that of a simulation test in rotorcarft. Finally, in case of high collision possibility, we presented the downsize length to avoid the collision and increment of non-protective area in flight, simultaneously.