• Geomechanics and Engineering
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• v.12 no.4
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• pp.627-637
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• 2017

The high positive correlation between plastic strain of loaded coal-rock and AE (acoustic emission) characteristic parameter was studied and proved through AE experiment during coal-rock uniaxial compression process. The results show that plastic strain in the whole process of uniaxial compression can be gained through the experiment. Moreover, coal-rock loaded process can be divided into four phases through analyzing the change of the plastic strain curve : pressure consolidation phase, apparent linear elastic phase, accelerated deformation phase, rupture and development phase, which corresponds to conventional elastic-plastic change law of loaded coal-rock. The theoretical curve of damage constitutive model is in high agreement with the experimental curve. So the damage evolution law of coal rock damage can be indicated by both acoustic emission and plastic strain. The results have great academic and realistic significance for further study of both AE signal characteristics during loaded coal-rock damaged process and the forecasting of coal-rock dynamic disasters.

• Journal of the Korean Society of Clothing and Textiles
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• v.2 no.2
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• pp.277-286
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• 1978

The history of the women's veil which was used to hide their face in Yi-Dynasty was discussed. The similar fashion of wearing veil was popular in T'ang China as Myok-li and Yoo-Mo, then it might have influenced the fashion of the women's dress of the Silla Dynasty. It was also found out that the custom was most popular in Koryo and then continued to Yi-Dynasty. The confucianism of Yi-Dynasty requested very strict moral obligation toward women that veil had to be worn by them whenever going out. It might not be their popular fashion but obligation. There were several types of veil so called; Neoul(라원) Jangott(장의) Suege-China(쓰개치마) Chun-eue(천의) Sak-kat(삿갓) Chun-mo(천모)etc., which were used as a part of formal dress for women. From the late 1930, when the new society started to accept women's activities, the customs of wearing veil had been vanishing from the women's dress.

• Research in Mathematical Education
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• v.15 no.2
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• pp.105-114
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• 2011

During the 20th century, the secondary school mathematics teaching in China had been developing from the an old-style private school form with individual instruction to classroom teaching with Chinese characteristics, which experienced three stages of development; the stage for the formation of modern teaching system (1902-1949), the stage for development (1950-1976), and the stage for innovation (1977-2000). The characteristics and journey for the transformation will exert great for reference and effects for the reform of secondary school mathematics teaching nowadays.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.11-16
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• 2012

During the 2009 global economic downturn, the dairy industry was also affected. Global milk production had gradually decreased, and the dairy industry was failing. However, in 2010, China's sudden consumption increase of dairy products, the price of dairy products recovered due to the great demand in China. The Asian continent as a whole played a significant role in maintaining the health of the global dairy industry, by preventing its total collapse. Currently, the price of all dairy products, except that of whole milk powder, has increased. The International Dairy Federation (IDF) expects that milk production will grow by 2% annually over the next 10 years, owing to Asia's high demand for all kinds of dairy products.

• Publications of The Korean Astronomical Society
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• v.14 no.2
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• pp.129-137
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• 1999

We arranged ancient Korean calendar during Koryo dynasty (A.D. 918-1392) according to Julian calendar. We used two representative history books, Koryo-sa (高麗史) and Koryo-sa Jeolyo (高麗史節要), which contain thea stronomical and the historical records chronologically. We found all 19,727 ganji dates(日辰) and 102 misrecoreded ganji dates in two books. Most of the data are arranged based on those two books, and doubtful data are identified using the eclipse, historical events and lunar phase calculations etc. Although Korea, China, and Japan were using basically the same calendar since ancient times, their calendars show some significant disagreement. We found that arranged chronological tables during Koryo dynasty were, in some cases, different from those of China and Japan.

• International Journal of Railway
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• v.1 no.2
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• pp.45-58
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• 2008

The concept of lean production originated and was applied mainly to manufacture industries Even proven successful with such companies as Toyota, lean production has to be combined railway transportation production in order to bring its function into full play. The paper analyzes for applicability of lean production in railway transportation production organization, puts forward implementation methods such as transportation resource integration, station-zone organization, dispatch command optimization, railway performance evaluation index system, etc., and makes an exemplification study of lean production of Urumqi Railway Bureau in China, which testifies the applicability and efficiency of railway lean production.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.125-129
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• 2006

This paper presents the isolation and performance evaluation of PV systems installed at Tibet area of China in order to identity the key factors that determines system operation at a severe climate conditions and promote the cooperation of PV technology between Korea and China. The installed systems consist of 100kW on-grid connected PV systems, BOS(balance of systems), data acquisition and transmission equipments. The Korea side supplied the solar cell, BOS like as inverter, control box and monitoring system. And the Chinese side assembled solar module by using Koreans solar cells, constructed site and built control house.

• Wind and Structures
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• v.1 no.1
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• pp.67-75
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• 1998

Tiger Gate Bridge, a steel suspension bridge with a main span of 888 m and a stiffening box girder, is located at the Pearl River Estuary, Guangdong Province, one of the typhoon-prone area in China. Focusing on the developing of the full aeroelastic model of the bridge and simulation of the wind field of the bridge site in a large boundary wind tunnel at Tongji University, Shanghai, China, some main results about the wind resistant properties of the bridge including aerodynamic instability, buffeting responses both being in operation and erection stages by using of a full aeroelastic model wind tunnel testing are introduced. Some of analytical approaches to those aerodynamic behaviours are also presented, and compared with experimental data of the testing.

• The Journal of Korean Medical History
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• v.34 no.2
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• pp.79-87
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• 2021

The civil service examination system is an important part of the history of education in East Asia. In China, the civil service examination system lasted for almost 1,300 years. Through this, each dynasty was able to prevent the concentration of power to the hereditary nobles and to give competent talents an opportunity to rise to an important position in the state. In terms of medical education, in China, doctors have already been selected through tests since the Song Dynasty. However, the actual cases of medical tests currently remaining in each dynasty are very rare. This paper, firstly, examines the implementation method of the medical test during the Qing Dynasty and examines how it influenced the merit rating. and secondly, this paper examines the actual cases of the remaining Qing medical exam questions, in terms of content, related to the medical text "Uijonggeumgam (醫宗金鑑)" and was influenced by the style of the civil service examination at that time.

• KDI Journal of Economic Policy
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• v.43 no.1
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• pp.53-80
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• 2021

The main objective of this study is to determine whether there have been TFP increases in the Korean manufacturing sector due to trade liberalization since the 1990s. Based on the methodology proposed by Pavcnik (2002), which focuses on the channel through which trade liberalization measures enhance overall industrial productivity by triggering the exit of low-productivity firms, this study tests the following two hypotheses: first, the TFP increase in the Korean tradable industry is not higher than that in the non-tradable industry, and second, plants with lower TFP levels did not exit from the tradable industry. Through the rejection of these two hypotheses, it is possible to infer indirectly the effect of trade liberalization on firm productivity rates in Korea since the 1990s. First, this analysis reveals that since the 1990s, the TFP of the tradable sector compared to the non-tradable sector presented a statistically meaningful increase only in the 2000s, when China joined the WTO and trade increased sharply between Korea and China. Secondly, TFP growth in the tradable sector was positively affected by exits, as it was plants with lower TFP levels that ceased to exist.