• 수도
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• s.4
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• pp.30-33
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• 1975

• 베이커리
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• no.10 s.363
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• pp.132-134
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• 1998

• KIPE Magazine
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• v.25 no.4
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• pp.56-61
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• 2020

• 월간산업보건
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• s.173
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• pp.51-55
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• 2002

• River and Culture
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• v.6 no.4
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• pp.37-42
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• 2010

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.12 no.1
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• pp.44-49
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• 1999

In this study, microstructure and electrical conductivity of {(G $d_2$ $O_3$)$_{0.75}$( $Y_2$ $O_3$)$_{0.25}$}$_{x}$ (Ce $O_2$)$_{1-x}$ (0.01$\leq$x$\leq$0.25) was investigated as a function of composition x. GYO addition(x) increased the bulk density and G $d_2$ $O_3$ was found to be monoclinic at x>0.15. From the change of the lattice parameter with the addition(x), GYO solution limit for ceria was exceeded in the range of x=0.05 to 0.09. Thermal expansion coefficient(15~17$\times$10$^{-6}$ $^{\circ}C$) of GYC samples at x=0.01 to 0.07 was higher in value than that of 8YSZ(10.8$\times$10$^{-6}$ $^{\circ}C$). The electrical conductivity of GYC samples at x=0.05 showed the maximum(0.01S/cm) in value at 1073K which was 2 times higher than that of 8YSZ. The activation energy for the electrical conduction was determined to be 0.60eV in the temperature range of 1073K.3K..3K.

• Journal of Sasang Constitutional Medicine
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• v.20 no.3
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• pp.21-39
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• 2008

1. Objectives The purpose of this study was to find out associations between "HamsanSachon DongyiSuseBowon GaboGubon" and "SangGyoHyeonTo DongyiSuseBowon" 2. Methods A comparative study of authors, colophons, tables of contents and texts of "HamsanSachon DongyiSuseBowon GaboGubon" and "SangGyoHyeonTo DongyiSuseBowon" was made. 3. Results and conclusions 1) There was a close connection between "HamsanSachon DongyiSuseBowon GaboGubon" and "SangGyoHyeonTo DongyiSuseBowon", compared their authors, colophons, tables of contents, texts, and so on. 2) It is supposed that "SaSangInByeonJeungRon" of "HamsanSachon DongyiSuseBowon GaboGubon" was not added any touches and "SaSangInByeonJeungRon" of "DongyiSuseBowon" (GyeongJaBon) was not revised. 3) "DongyiSuseBowon GaboGubon BokWonBon" and text of "SaSangUiHak" shold be amended partially.

• Journal for History of Mathematics
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• v.19 no.3
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• pp.1-20
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• 2006

The administrative service in Chosun Dynasty relating to mathematics was carried out by the middle class(中人) mathematicians selected by the official selection examination(取才). They belong to HoJo(戶曹) department and their ranks are GyeSa(計士), ByulJe(別提), HunDo(訓導 = mathematics teacher), and GyoSu(敎授 = mathematics professor). We call them SanWon(算員). HunDo and GyoSu played very important role although their ranks are low, for they educate SanWon and manage the official selection examination. Using JuHakSeonSaengAn(籌學先生案, List of mathematics teachers) and JuHakIpGyukAn(籌學入格案, List of successful candidates in the official selection examination for mathematics), we investigate HunDo and GyoSu in Chosun Dynasty.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.273-286
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• 2019

A derelict bridge called WoljungGyo was restored in Gyeongju, the capital city of ancient Silla. WoljungGyo was originally built in 760AD, and later rebuilt in 1280AD during the Goryeo Kingdom. The bridge lasted in working condition for at least 520 years. The bridge was uncovered to the remains of both abutments and four piers, with only one or two steps remaining. One of the foundation for piers showed evidence of partial settlement. The cause of the partial settlement is important for the successful restoration of the bridge so that an extensive investigation was carried out, which includes layer stratification by boring, 2-D stiffness profiling by surface-wave tests, and large scaled-plate load test for evaluating capacity. In addition to the field studies in the Woljunggyo bridge, 3-D finite element analysis was also conducted. Based on the results of the site investigation and the numerical analysis, it was concluded that the further ground improvement to build the piers was not necessary so that the gravels were placed and leveled underneath the existing pier stones to compensate partial settlement before the restoration.

• Journal of Korea Water Resources Association
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• v.41 no.8
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• pp.845-854
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• 2008

The old bridge of Woljeong-gyo, which has the fluvial history and culture, represents the ancient construction and civil engineering techniques. It is the oldest stone bridge in Korea and currently restored with its vicinities. In this study, the experimental model was used to analyze the hydraulic characteristics, the local pier-scour depth without scour protection, and the stability of riprap protection using the old grid type panels and stones for Woljeong-gyo of the study area. The water levels were increased around 30cm due to the restored bridge piers and foundations and the effects went up to 200m upstream. The maximum scour depth of 5.4m was measured and the scour protection tests were performed with the riprap size calculated using empirical equations and the existing scour protection range. The riprap of the existing scour protection in the upstream side was broken away, while the riprap of extended scour protection was very stable for the design flood condition of Woljeong-gyo area.