• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.194-198
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• 2012

This paper describes flying inspection apparatus for 22.9kV distribution line. This apparatus is composed of multi-copter(more than 4 propellers), camcorder and remote controller. The existing inspections, such as hot-line inspection job and optical inspection method and distribution Line Checking Robot, have many restrictions. A electric working vehicle and hot-line job license are essential in hot-line inspection job. Besides its high cost, it can't be applied to the electric pole over 18m and road-blocked area. Optical method can't inspect upper side of electric facilities mounted on the electric pole. Robot method can't be applied to the corroded overhead earth wire and nothing of overhead earth wire. To solve the problems, in Korea Electric Power Co., we have applied flying inspection apparatus to the 22.9kV distribution line. The results of trial application show that this paper is practical and effective for the inspection technical method in 22.9kV distribution line

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.172-173
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• 2021

In recent, unmanned Aircraft Systems (UAS) have been widely used for various purposes, such as safety inspection, facility condition inspection, progress monitoring, in the architecture engineering, and construction (AEC) industry. This technology can provide visual assets regarding the conditions of construction jobsites as well as constructed facilities during flying over the point of interests. With the significant interests in this advancement, the recent studies have presented how the UAS can be applied fro different types of facilities (e.g., buildings, power genereation systems, roads, or bridges) to inspect the current conditions of them for safe operations as well as public's safety. This study reviewed the receent studies to document their scientific findings and practical contributions, as well as provided the overview of further implications for future studies.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.143-151
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• 2007

This study presents the experimental results of frost durability including resistance to freezing-thawing and surface scaling of concrete. Mixing design was proportioned with the various water-binder ratio between 0.37 and 0.47 and three different binder compositions corresponding to Type I cement without any supplementary cementitious materials(OPC), Type II cement with 50% blast-furnace slag replacement(BFS50), and ternary cement with Type III cement, 15% fly ash, and 35% slag replacement (BFS35%+FA15%). Test results showed that the mixing design with BFS50% and BFS35%+FA15% exhibited higher durability factor than that made with OPC only. Finally, the use of blend cement containing slag can be used effectively in terms of frost durability of the concrete exposed to severe condition under coastal environment like as flying salt, sea water spray, etc.

• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.196-202
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• 1996

The effect of cooking(boiling, steaming and baking0and drying on the cholesterol content and formation of oxidized cholesterols in quid(Japanese flying squid, Todarodes pacificus) was studied. Cholesterol content of live squid meat varied with the portion sampled, and results from spectrophotometric assay ranged from 263.2mg/1..g(mantle) to 315.8mg/100g(tentacle). The cholesterol levels analyzed by gas chromatography(GC) for squid samples were lower by 7% of total cholesterol for live squid meat and 24% for processed meat than those results by spectrophotometric assay. Cooking resulted in the decrease of the initial total cholesterol content of raw meat from 10%(boiling for 5min.) to 25%(steaming for 5min.) The amounts of cholesterol remaining after baking were 68% for microwave oven samples and 64% for convection oven samples. Drying of raw tissue caused the greater reduction in cholesterol content than cooking but showed no significant difference in samples stored for 6 weeks at 4$^{\circ}C$ and 2$0^{\circ}C$. Raw squid meats contained essentially no oxidized cholesterols, while the 22-hydroxychoesterol was detected in frozen meats. The additional oxidized cholesterols as cholestane-triol was indentified with 22-hydroxycholesterols in cooked samples. Sun dried meat stored at 4一 and 2$0^{\circ}C$ for 6 weeks had the three kinds of oxidized cholesterols such as 22-hydroxycholesterol, cholesta-3,5-dien-7-one and cholestane-triol.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.59-67
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• 2022

In this study, the monthly airborne chlorides flying into the offshore bridges were investigated depending on the sea level. The target structures were 9 bridges located on the western and southern coast of South Korea. The airborne chlorides were measured at different sea levels on each bridge every month during 1 year. The results showed that the strongest seasonal wind from the northwest in winter expecially have led increase of the airborne chlorides, and its effect was more significant in the western coast than the southern coast. It was also found that the airborne chlorides declined with the increase of sea level. Three types of curves were suggested for analyzing the decrease trend with the sea level, based on the airborne chlorides at the lowest measurement height of main tower. The trend was varied depending on the sea area, and even in the same sea area, the local topographic condition affected the airborne chlorides. It means that the location and local topography should be considered simultaneously for durability management in the framework of the chloride source, and then the influence of the chloride source should be classified, e.g. safe and dangerous. From these results, it is expected that it could be used as baseline data for the evaluation of the deterioration environment in the Detailed guidelines for safety and maintenance of facilities [Performance evaluation]_Bridge.