• Restorative Dentistry and Endodontics
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• v.29 no.5
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• pp.439-445
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• 2004

The purpose of this study was to evaluate the influence of plugger penetration depth on the apical extrusion of root canal sealer during root canal obturation with Continuous Wave of Condensation Technique. Root canals of forty extracted human teeth were divided into four groups and were prepared up to size 40 of 0.06 taper with ProFile. After drying. canals of three groups were filled with Continuous Wave of Condensation Technique with System $B^{TM}$ and different plugger penetration depths of 3. 5, and 7 mm from the apex. Canals of one group were filled with cold lateral compaction technique as a control. Canals were filled with non-standardized master gutta-percha cones and 0.02 mL of Sealapex. Apical extruded sealer was collected in a container and weighed. Data was analyzed with one-way ANOVA and Duncan's Multiple Range Test. 3 and 5 mm penetration depth groups in Continuous Wave of Condensation Technique showed significantly more extrusion of root canal sealer than 7 mm penetration depth group (p < 0.05). However, there was no significant difference between 7 mm depth group in Continuous Wave of Condensation Technique and cold lateral compaction group (p < 0.05). The result of this study demonstrates that deeper plugger penetration depth causes more extrusion of root canal sealer in root canal obturation by Continuous Wave of Condensation Technique. Therefore, special caution is needed when plugger penetration is deeper in the canal in Continuous Wave of Condensation Technique to minimize the amount of sealer extrusion beyond apex.

• Journal of Advanced Navigation Technology
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• v.16 no.2
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• pp.360-366
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• 2012

In the power distribution panel installed in airport or industrial facilities, MCCB has been used for main switch and ELCB for branch switch to perform human body and leakage-inducing fire protection as well as overcurrent and short circuit protection. Especially for the airport panel, increase in accident protection is needed for stable power supply due to rapid modernization with fast-growing users, higer capacity and diversification of equipment, the increase of power capacity and the breaker made slim is a main issue for now because the issue for installation space is standing out by making panel with two-row arrangement connection method, etc. due to a many use of branch ELCBs. In this thesis, we designed arc extinguishing mechanism, considered movement direction change of contact in mechanism design. Also, we designed the breaker to work stably in case of miniaturization of leakage detection circuit and reverse connection. We conducted short circuit test to verify its function and developed the breaker that can be improved protection against accidental current with slim size operating leakage function when reverse connection to help solve the problem in using space that is increasing in the airport distribution panel.

• KOMUNHWA
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• no.57
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• pp.195-210
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• 2001

One kiln site of Koryo Earthenware in Hwakok-ri, Ansung was excavated from March 15, 1999 to May 15, 1999 by Museum Team of Ehwa Women's University, and also other one earthenware kiln site was confirmed as exposed figure on the ground. In this study, the

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.405-412
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• 2015

Forty schools having natural turf playgrounds were investigated by on-spot investigation and oral interviews with relevant school officials to find out basic information on turfgrass management practices of school playgrounds in Gyeonggi province. Average area of playground was $3,890m^2$ per school and $12m^2$ per student. Ninety five percent of turf playgrounds were managed by school staff and ninety percent of schools spent less than 5 million won per year for turf management. The difficulties in turfgrass management were considered as a major challenge for the schools, followed by turfgrass management cost. Among the management practices, school officials pointed out weed management as the most difficult work, followed by irrigation. The average number of fertilization and mowing was 2 and 6 times per year, respectively. About the half of playgrounds were irrigated only when there was wilting symptom. Zoysiagrass was the most popular choice for the school playgrounds and only three school playgrounds were established with pop-up irrigation system. Fourteen school playgrounds had good turf quality but the rest of school playgrounds had inadequate turf quality requiring minor or full renovation.

• Restorative Dentistry and Endodontics
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• v.31 no.1
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• pp.66-71
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• 2006

To evaluate the ratio of gutta-percha area in the canal after canal obturation with Continuous Wave of Condensation Technique (CWCT) with varying depths of plugger penetration, forty root canals of extracted human teeth were prepared up to size 40 of 0.06 taper with $ProFile^{(R)}$. Canals of three groups were filled with CWCT with System $B^{TM}$ (Analytic Tech. , USA) and different plugger penetration depths of 3, 5, or 7 mm from the apex. Canals of one group were filled with lateral condensation technique as a control The felled teeth were cross-sectioned at 1, 2 and 3 mm levels from the apical foramen. The ratio of gutta-percha area in the canal was analyzed using $Auto^{(R)}$ Cad 2000. Data were analyzed with one-way ANOVA and Duncan's multiple range test. At all levels, higher gutta-percha area ratio was found with deeper plugger penetration depth in CWCT, and cold lateral condensation group showed higher ratio than group of plugger penetration to apical 7 mm in CWCT. At apical 1 mm and 2 mm levels, group of plugger penetration to apical 3 mm showed significantly high or gutta-percha area ratio than those of apical 7 mm and lateral condensation (p<0.05). It is concluded therefore that, under the conditions of the present study, deeper plugger penetration depth results in more favorable and efficient obturation in CWCT.

• Fire Science and Engineering
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• v.28 no.5
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• pp.8-13
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• 2014

The purpose of this study is to analyze the damage pattern when overcurrent is applied to a thermal magnetic type molded case circuit breaker (MCCB) using a Primary Current Injection Test System (PCITS). When an overcurrent of 150 A was applied to the PCITS for 5 seconds with the trip bar of an MCCB being damaged, it was found that the surface of the temperature control device (bimetallic strip) positioned at the right was significantly carbonized. When an overcurrent of 300 A was applied to the PCITS for 5 s under the same conditions, the entire temperature control device was deteriorated, becoming flattened and in close contact with the MCCB. When an overcurrent of 450 A was applied to the PCITS for 5 s, the coil of the temperature control device was melted and disconnected. In addition, it was observed that the contacts, the enclosure and upper cover were deformed and there was a trace of carbonization on them. When approximately 3 s had elapsed after an overcurrent of 600 A was applied, white smoke occurred inside the MCCB and a flame was radiated out, after which the overcurrent supply stopped with "phutt" (whomp) sound. It was observed that when the same type of MCCB is damaged by a general flame, the surfaces of its handle, terminal, arc divider (extinguisher) and temperature control device were carbonized uniformly. In addition, it was found that the trip bar of the operating mechanism was melted down and the metal operation pin was moved while being tripped.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.535-541
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• 2019

The purpose of this study was to investigate the possibility of fishery in offshore wind farms and evaluate the risk linked to the presence of turbines and submarine cables in these areas. With this objective, we studied an offshore wind farm in the Southwest Sea and the current state of vessels in the surrounding National Fishing Port. The risk assessment criteria for 22 fishing gears and methods were set by referring to the fishing boats; thereafter, the risk was assessed by experts. The fishing gears and methods that could be safely operated (i.e., associated with low risk) in the offshore wind farm were: single-line fishing, jigging, and the anchovy lift net. The risk was normal so that it is possible to operate, but the fishing gears and methods that need attention are: the set long line, drifting long line, troll line, squid rip hook, octopus pot, webfoot octopus pot, coastal fish pot, stow net on stake, winged stow net, stationary gill net, and drift gill net. Moreover, the fishing gears and methods difficult to operate in the of shore wind farm (i.e., associated with high risk) were: the dredge, beam trawl, and purse seine. Finally, those associated with very high risk and that should not be allowed in offshore wind farms were: the stow net, anchovy drag net, otter trawl, Danish seine, and bottom pair trawl.

• The Journal of Korean-Japanese National Studies
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• no.21
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• pp.1-43
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• 2011

This article introduces Abe Mituie's activities related to Korean and Japanese Buddhism and two newly discovered materials. He worked as a brain of Japanese cultural rule over Joseon Korea while holding various positions such as the president of KyeongSung Il Bo, the vice president of Kokmin Newspaper and the director of Central Joseon Association. Abe was responsible for Enkak Temple, the head temple of Japanese Rinzai section, and was one of the layman followers of Syak Soen who worked for the spread of modern Japanese Buddhism to Europe and America. He was a respectful Buddhist layman so as to teach Zen Buddhism for young Buddhist monks in Japan. After he started to assume charge in the Kyeong Sung Il Bo, he was also very active in movements in relation to Joseon Buddhism to the extent that he was found to be deeply involved in Joseon Buddhism sections. On the other hand, he concluded Joseon culture to be 'devastated.' He asserted that it was necessary to develop spiritual culture and revive Buddhism in order to resolve the devastation in the Joseon. In addition, he thought that Joseon Buddhism was ruined due to the misgovernment of the Joseon Dynasty, but had its own as great tradition as Japanese Buddhism. Therefore, in his opinion, there was a need to do research on Joseon Buddhism and find some way out of the contemporary difficulties. In order to save the situation, he made efforts to protect and revive Joseon Buddhism while paying continuous visits to Joseon Buddhist temples, supporting the publication of Buddhist canons and proposing to have a regular meeting of 'The Invitation of 30 Head Temples.' From his visit to Youngju Temple and his consistent relationship with Kang Daeryeon, it can be assumed that he was involved in reorganizing power structure in Joseon Buddhism and establishing various institutions. He emphasized the strict adherence of individuals and communities to rules in his lecture for students at Jung Ang Hak Rim. It was a way to revive Joseon Buddhism by creating a new social image of Joseon Buddhism. He continued to work for the restoration of Joseon Buddhism even after he retired from Kyeong Sung Il Bo and returned to Japan. He introduced the originality of Joseon Buddhism history to Japan and sent Japanese monks to Korea in order to do research and contribute to exchange between Korean and Japanese Buddhism. All things taken together, it is evident that Abe Mitzihe regarded Joseon as backward or stagnant from a perspective of evolutionist or orientalist, and was a Japanese elite to believe that it was just for Japan to control Korea. However, he was different from other Japanese elites in that he did not considered Joseon Buddhism merely as the object of propagation. He thought that Joseon Buddhism possessed its own great tradition and culture, but was ruined because of the misadministration of the Joseon Royal House. Therefore, in his opinion, Joseon Buddhism should be recovered by means of some supports, and its revival would lead to the restoration of Joseon culture as a whole, which would be realized by Japanese rule over Korea and Japanese elites' generous assistance.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.3
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• pp.117-123
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• 2006

The water quality before and after a typhoon was investigated as a part of a study on the increase of organic matter and on the fundamental measures to counter chemical oxygen demand (COD) in the eutrophic Soho coastal seawaters of Gamak Bay. The dissolved oxygen (DO) saturations were <54% when water column was stratified. The DO saturation was similar at surface and in the bottom layer after a typhoon $(78\sim88%)$, and a very high DO saturation (234%) was observed in the surface water after mass phytoplankton growth. The highest values of $NH_4-N,\;NO_3-N,\;PO_4-P$, and $SiO_2-Si$ were 18.22, 38.90, 1.58, and $52.10{\mu}M$, respectively, when freshwater entered after heavy rainfall events. In addition, high concentrations of $NH_4-N,\;PO_4-P$, and $SiO_2-Si$ were detected with low DO saturations in bottom water (>5m). A maximum chlorophyll (Chl.) concentration of $311.0{\mu}gl^{-1}$ was observed after typhoon, when a high-density Scrippsiella trochoidea red tide occurred with cell density of 42,000 cells $ml^{-1}$. The algal growth potential (AGP) was high after the typhoon. Nitrogen was always a limiting nutrient for phytoplankton growth. The highest COD level was $10.55mgl^{-1}$, and the main reason of the variation in COD was likely to be phytoplankton growth $(r^2=0.612,\;p=0.000)$. Organic matter, which entered the water column when the typhoon stirred the sediments, seems to have little effects on COD increase.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.161-169
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• 2005

With various Korean domestic soybeans, growth and yields analysis were conducted to select the suitable soybean cultivars for cultivation in paddy field. Distinctive aspects of the soybean growth were observed in paddy field such as retarded growth of top plants and roots, relatively higher T/R ratio followed by overgrowth of top plant. However, growth and yields were significantly different among the cultivars showing 134kg/10a in Paldokong and 385 kg/10a in Doremikong. At V5. and R2 stage, highly positive correlations $(r=0.76^{**}\~0.91^{**})$ were observed between leaf area and dry weight of top plant and/or root. T/R ratio was negatively correlated with dry weight of root $(r=-0.37^*)$ at V5 stage, while significantly correlated with leaf area $(r=-0.37^{**})$ and dry weight of top plant $(r=0.65^{**})$at R2 stage. Among the characters, only 100-seed weight was significantly correlated with yield. Considering the growth characters, 37 cultivars could be included in 3 different groups and genotypic properties such as maturity and growth habit were similar in each group. Nine cultivars in group 1 showed retarded growth from V5 to R2 stage, relatively lower T/R ratio, and good seed ripening. Average yields of the cultivers was 257kg/10a. In group 2, 12 cultivars showed higher T/R ratio due to overgrowth of top plant and lowest average yields (230 kg/l0a) due to poor seed ripening. Sixteen cultivars in group 3 grew fast from V5 to R2 stage representing late maturity traits, low T/R ratio, and good seed ripening. Average yields of the cultivars was highest among groups showing 270kg/l0a. In results, stable self-sufficiency of soybean yields could be expected by selective cultivation with high yielding cultivars ranging from 301 to 385kg/10a, such as Shinpaldalkong 2, Sohokong, Doremikong, Keumkangkong, Bukangkong, Dajangkong, and Geomjeongkong 2, or with cultivars included in group 3.