• Journal for History of Mathematics
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• v.22 no.4
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• pp.1-14
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• 2009

Since western mathematics and astronomy had been introduced in Chosun dynasty in the 17th century, most of Chosun mathematicians studied Shu li jing yun(數理精蘊) for the western mathematics. In the last two decades of the 19th century, Chosun scholars have studied them which were introduced by Japanese text books and western missionaries. The former dealt mostly with elementary arithmetic and the latter established schools and taught mathematics. Lee Sang Seol(1870~1917) is well known in Korea as a Confucian scholar, government official, educator and foremost Korean independence movement activist in the 20th century. He was very eager to acquire western civilizations and studied them with the minister H. B. Hulbert(1863~1949). He wrote a mathematics book Su Ri(數理, 1898-1899) which has two parts. The first one deals with the linear part(線部) and geometry in Shu li jing yun and the second part with algebra. Using Su Ri, we investigate the process of transmission of western mathematics into Chosun in the century and show that Lee Sang Seol built a firm foundation for the study of algebra in Chosun.

• Resources Recycling
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• v.19 no.2
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• pp.63-72
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• 2010

The patents were searched to investigate the trend of recycling technologies about plastic waste. Database was collected from WIPS site and the range of the search was limited to patents opened in U.S.A (US), European Union (EU), Japan (JP) and Korea (KR) to september 2009. In this paper, 4,795 patents were selected by investigation abstracts and the trend of the recycling technologies relating to waste plastic were investigated through the analyzing by the years, countries, companies. The patents were occupied 65% by Japan and the most of the patents were about chemical recycling. In the case of Korea, material recycling was major in the patents of waste plastic recycling.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.267-276
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• 1979

This research was conducted to evaluate tile effects of polluted Suyeong River water on the water quality of Kwangan-Ri bathing beach. The quantity of pollutant loading of Suyeong River was determined in January 1979, and the directions of tidal currents and the chemical constituents of the Suyeong Bay water were observed in May 1979. The results are as follows: The quantity of total pollutant loading which was discharged into Suyeong Bay is: BOD 75.2ton/day; COD 96.9ton/day; SS 20.5ton/day; ammonia-nitrogen 12.4ton/day; nitrate-nitrogen 430kg/day; nitrite-nitrogen 85.1kg/day; phosphate-phosphorus 594kg/day and total heavy metals 3.01ton/day. Considering the tidal current, the polluted waters of Suyeong River flow off the Kwangan-Ri beach during tile ebb tides, and flow into the Kwangan Ri beach during the flood tides. Consequently, the water quality of Kangan-Ri bathing beach is not suitable for bathing.

• The tire
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• s.70
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• pp.30-32
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• 1977

일본의 재생타이어의 이용도도 매년상승하고 있다. 74년말에 수집된 수급조사에 의하면 8년간에 약 4배의 신장을 보이고 있다. 연이나 75년의 동업계는 신품타이어의 안가, 난매공세들에 눌려서 일부가격 붕괴, 채산악화, 조단도보여 불신을 극했다. 또 75년도의 실적은 미파악이나 미국처럼 TB용의 수요감과 반해서 승용차용, 소형트럭용의 대폭적인 신장이 있었을 것 같으며 또 불황의 영향에 의한 일반사용자의 사용량도 증가한 것으로 보여져 그 실적이 주목된다. 국내의 수급상황은 자료가 수집되는 것을 기다리기로 하고 금번은 75년의 봄에 법석였든 미국재생타이어업계의 현황을 탐색에 보았다. 아크론 러버어그룹의 리차아드. W. 액카아트씨의 「재생타이어의 에너지위기의 영향」이라고 제하는 리포오트는 상4담히 자미가 있는 자료이다. 동리포오트는 다음과 같이 결언하고 있다.

• The tire
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• s.45
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• pp.20-24
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• 1973

자동차타이어의 최대의 유리성은 공기를 잘 활용하는 데 있다. 그러나 일단 공기를 잃은 타이어는 즉시 사용불능으로 화하고수리는 할 수 있어도 시간과 수리라 하는 큰 로쓰를 초래하는 결과가 된다. 그래서 과거 80년간 많은 타이어 기술자는 빵꾸라고 하는 현상으로부터 탈출할 수 있는 타이어의 개발에 어느 정도의 노력과 지혜를 짯었는가? 동경의 타이어…라고 하면 "노우 빵꾸 타이어"라고까지 일컬어진다. 그것은 시대가 고속화에로 진입함에 따라 빵구는 귀중한 생명까지도 빼았는 큰 사고를 초래하는 원인의 하나로도 되어 왔든만큼 더욱 중대성을 가져왔다. 이때문에 절대로 빵구나서는 곤란하다고 하는 용도의 차량에 장착된 타이어에 대해서는 승차감, 속도 등의 요구는 무시하고서 이미 여러 가지의 노우 빵꾸 타이어가 제조되고 있다. 그렇다고 해서 보급의 속도와 보통의 승차감의 노우 빵꾸 타이어는 생각할 수 없는 것일까?…이러한 발상으로부터 개발된 타이어에 "파아마포옴 타이어"라고 하는 것이 있다. 매이커어는 미국의 굳이어 이다. 그럼 그 마아마포옴 타이어란? ……간단히 말하면 중의 공기를 스폰지상의 포옴재로 한 것이다. 따라서 승차감은 결코 나쁘지 않다. 속도도 50km까지라면 염려없다. 하나 그 타이어의 제조법이 간단하지가 않다. 특히 "열처리의 단계에서 포옴재를 타이어의 속에 균등하게"라고 하니 큰 일이다. 이하는 일본 굳이어 타이어 기술부에 의한 파아마 포옴 타이어의 개설.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.73-76
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• 2011

최근 건축물에서 공동주택의 비율이 증가하고 있으며 동시에 공동주택의 화재비율도 증가하는 경향을 보이고 있다. 또한 화재 시 인명 피해의 주원인인 가연물은 소재가 다양화되고 있으나 안정성 보다는 디자인, 기능성에 치중되어 그에 따른 화재 위험성도 커져가고 있다. 따라서 본 연구는 전보의 실내장식물에 이어 공동주택에서 많이 사용되어지는 적재가연물을 가연물 조사를 바탕으로 선정하여 Furniture Calorimeter를 이용해 그 연소특성을 알아보았다. 그 결과, 소파가 타 시료에 비해 화재 시 높은 위험성을 나타냈으며, 일본건축학회에 발표된 데이터와 비교한 결과 소파의 데이터가 유사한 것으로 나타났다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.487-492
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• 2010

최근 건축물은 초고층화 대형화 지하심층화 등으로 변모하고, 더나아가 복합화가 진행되고 있다. 이러한 건축물은 화재 발생 시 기존의 건축물보다 큰 인재로서 다가오며, 특히 연기로 인한 피해가 주를 이루고 있다. 하지만 국내의 경우 연기의 피해에 따른 피난용량설정 및 계획 등에 관한 연구가 미흡한 실정이다. 따라서 본 연구는 이에 대하여 일본의 BRI2002 모델의 알고리즘분석에 따른 피난 안전과의 연계성 방안을 도출하여, 향후 국내의 연기를 중심으로한 피난용량설정방안에 대하여 서술하였다.

• Journal of Convergence for Information Technology
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• v.12 no.4
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• pp.303-315
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• 2022

This study compared and analyzed Japan and China, two major competitors to Korea, in the male cosmetics market, which has been shifted dramatically by the outbreak of COVID-19, with implications for the ASEAN market in mind. Questionnaire copies collected from 300 men in Generation MZ living in Korea, China, and Japan were used for analysis, and SPSS 21.0 was used to conduct a statistical analysis of the collected questionnaires. The following are this study's results: First, this study identified their purchase behaviors. The average amount of money the male respondents spent on buying cosmetics was below KRW 30,000 in Korea, China, and Japan. Functionality and texture ranked as top factors contributing to cosmetics purchases in all the three countries. Second, with regard to brands preferred by the respondents, Korea and China were open to foreign brands, while Japan mostly preferred its domestic brands. Functionality and texture ranked as top factors contributing to cosmetics purchase in all the three countries. Second, with regard to brands preferred by the respondents, Korea and China were open to foreign brands, while Japan mostly preferred its domestic brands. Third, this study found changes in the use of cosmetics since the outbreak of COVID-19. The respondents' biggest skin concern since COVID-19 was acne in Korea and Japan and increased sebum excretion in China. Concerns about sebum were commonly ranked high across the three countries. Based on these results, this study is suggested as a reference to improve the export competitiveness of Korean male cosmetics in the ASEAN market.

• Conservation Science in Museum
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• v.10
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• pp.43-61
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• 2009

The Buyeo National Museum was requested conservation treatment for wooden objects excavated from three Baekje archeological sites: Neungsan-ri, Ssangbuk-ri, and Gungnamji Pond. Prior to conservation treatment, analysis was conducted to identify the species used. The results of the analysis revealed wood from diverse species of trees including Hard pine, Cryptomeria japonica D. Don, Zelkova serrata Makino, Quercus spp., Platycarya strobilaceae S. et Z., Castanea spp., Torreya nucifera S. et Z., Taxus cuspidata S. et Z., and Salix spp. A high percentage of the objects were made of Cryptomeria japonica D. Don., a species native to Japan, which indicates that exchange with Japan was active at that time. Among the wooden objects, we analyzed lacquer fragments from six pieces of lacquerware, and the characteristics of the lacquer fragments were peculiar to specific artifacts. Most of the fragments were thicker than 100 ㎛. Pure lacquer and mixed black pigment were used. Infrared spectroscopy of the lacquered wooden fragments revealed that they had a very similar absorption band as refined lacquer, confirming that they were painted with lacquer. For their conservation, we immersed the objects in a high molecular weight aqueous solution of PEG#3,350 (10% → 50%) to strengthen them before vacuum freeze-drying.

• Journal of the Korean Geographical Society
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• v.50 no.6
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• pp.717-734
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• 2015

The Toyo Bunko (東洋文庫) in Tokyo, Japan is one of the largest library that holds the Korean old geographical documents. About 200 topographies of counties and prefectures, including Giinhansangnyang 杞人間商量 which recorded compilation and improvement plan of the geographical annals belong to it. Several maps and geographical annals of Joseon Period possessed in the Toyo Bunko are set high values on geography since the materials are only belong to it and have not yet been found in Korea. There are very important map collections including six copies of Daedongyeojido 大東輿地圖(1861, 1864) by Kim Jeongho(金正浩) and Suseonjeondo 首善全圖 by Kim, Jungho, collectible stamp of Maema Kyosaku(前間恭作) is imprinted on it, and Gangyeokjundo 疆域全圖 and Dongyeodo 東輿圖 which made with 20-ri and 10-ri grid, owned by Sidehara Daira(幣原坦). Especially Gwanbukjido 關北地圖 which is the northern border map recorded the Lee Sam's(李森) preface who served as a military official of Hamgyeong and Pyeongan Province in early 18th century. These maps and some other maps have a historical value to supplement of the history of Korean Cartography.