• Structural Engineering and Mechanics
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• 제59권5호
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• pp.885-899
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• 2016

The energy-based approach to predict the fatigue crack growth behavior under constant and variable amplitude loading (VAL) of the aluminum alloy 2024 T351 has been investigated and detailed analyses discussed. Firstly, the plastic strain energy was determined per cycle for different block load tests. The relationship between the crack advance and hysteretic energy dissipated per block can be represented by a power law. Then, an analytical model to estimate the lifetime for each spectrum is proposed. The results obtained are compared with the experimentally measured results and the models proposed by Klingbeil's model and Tracey's model. The evolution of the hysteretic energy dissipated per block is shown similar with that observed under constant amplitude loading.

• 한국표면공학회지
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• 제36권3호
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• pp.234-241
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• 2003

SiC nanorod was synthesized directly on Si substrate using hexamethyldisilabutane and Fe catalyst with (111) direction. Fe acted a liquid catalyst at growth condition. Grown SiC nanorod has about 30nm diameter and $5{\mu}m$ length. SiC nanorod growth was divided by trro regions with diameter distribution. This diameter distribution were occurred by surface deposition at as - grown nanorod's surface by limitation of growth rate. At higher temperature, these division not occurred. Growth temperature and flow rates affected diameter and morphology of nanorods. With increasing flow rate of source gas, nanorod's diameter increased because of deactivation effect. Case of the increasing temperature, growth rate increased so deactivation did not occurred.

• Agribusiness and Information Management
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• 제6권1호
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• pp.1-11
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• 2014

The purpose of this study is to develop the growth prediction model that can predict growth and development information influencing on the production of citrus fruits. The growth model was developed to predict the floral leaf ratio, number of fruit sets, fruit width, and overweight fruits depending on the main period of growth and development by considering the weather factors because the fruit production is influenced by weather depending on the growth and development period. To predict the outdoor-grown citrus fruit production, the investigation result for the standard farms is used as the basic data; in this study, we also understood that the influence of weather factors on the citrus fruit production based on the data from 2004 to 2013 of the outdoor-grown citrus fruit observation report in which the standard farms were targeted by the Agricultural Research Service and suggested the growth and development information prediction model with the weather information as an independent variable to build the observation model. The growth and development model for outdoor-grown citrus fruits was assumed by using the Ordinary Least Square method (OLS), and the developed growth prediction model can make a prediction in advance with the weather factors prior to the observation investigation for the citrus fruit production. To predict the growth and development information of the production of citrus fruits having a great ripple effect as a representative crop in Jeju agriculture, the prediction result regarding the production applying the weather factors depending on growth and development period could be applied usefully.

• 한국도서관정보학회지
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• 제25권
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• pp.207-223
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• 1996

Nowadays, the wide spectrum of changes have been occurred in library world. It is essential for librarians to improve their professionalization standards to convert these changes into the o n.0, pportunity of growth. The device of improvement of professionalization standards is following: 1. Librarians have to receive formal and informal education and learn to advance in knowledge and skill concerning library affairs continually. 2. Self learning has to be transform into learning organization. 3. Education of Librarianship concentrate mainly in practical and technical study by this time but it is indispensable to develop the theory and philosophy of librarianship.

• 한국프랜차이즈경영연구
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• 제6권2호
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• pp.31-49
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• 2015

The purpose of this study was to propose a policy development plan for win-win growth between franchisor and franchisee by investigating success factors of win-win growth on the basis of the problems between franchisor and franchisee. There are many small scale franchise businesses in Korea that have not achieved an economy of scale compared to the developed countries. The conflicts between franchisor and franchisee have continued due to a lack of social trust which comes from an excessively high ratio of business failure and big firms' expansion into franchise business, then again, the perception of relations between the topdog and the underdog causes many problems. As franchise is the industry based on common people that helps service industry advance and competitiveness of the self-employed improve, it needs to be activated as the higher value-added business by promoting establishment of business and strengthening foundation of related industry. A matter of mutual cooperation and win-win growth between franchisor and franchisee is important not only for the sound development of franchise industry but also for the stable growth of nation's economy. Thus, this study suggested a policy development plan for win-win growth between franchisor and franchisee by analyzing success factor of win-win growth based on the problems between franchisor and franchisee. The results of the study provide the important strategic way towards mutual growth and maintaining cooperative relationship between franchisor and franchisee in Korean franchise industry.

• 한국게임학회 논문지
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• 제4권1호
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• pp.41-49
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• 2004

온라인게임을 중심으로 내수시장에서 생존경쟁이 치열해지고 있는 가운데 새로운 시장을 개척하는 것은 한국의 게임업계의 미래가 걸린 일이다. 최근 중국은 온라인 인프라 발달, 인터넷 속도 향상 등 여러 가지 요인으로 온라인 게임 인구가 급격히 증가하고 있고, 중국 경제 성장에 따른 구매력도 증대하여 국제 게임 시장은 중국을 주시하고 있다. 중국 온라인게임 시장은 높은 잠재력과 '대박'을 터트릴 수 있는 기회를 주는 황금알을 낳는 거대한 시장이라는 점에 이의를 제기하는 국내 게임업체들은 없다. 이런 매력 때문에 국내 많은 게임업체들은 중국진출을 시도했고, 시장진입을 위해 준비중이다. 하지만 중국실정에 대한 철저한 이해와 준비 없이 성급한 진출로 낭패를 보는 사례가 늘고 있어, 중국시장 진출이 쉽지 않다는 것을 보여준다. 이 시점에서 우리는 중국게임시장 현황을 체계적 분석이 필요하며, 철저한 준비와 장기적인 안목으로 충분한 사전조사로 단기간 수익을 생각하기보다는 미래에 대한 투자를 해야 한다.

• 천문학회지
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• 제36권spc1호
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• pp.155-161
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• 2003

In this article I review the past and current status of solar astronomy in Korea and present some future prospects. Along with a brief historical account on the introduction of modern astronomy to Korea, I describe in detail how solar astronomy in Korea has developed since its birth about 20 years ago. With education of solar astronomers at domestic universities and collaboration with foreign scientists in China, Japan and the U. S., there has been a rapid growth of solar physics in Korea in the past decade. For further advance of solar astronomy in Korea, Korean solar astronomers have to build their own observing facilities and develop instrumentation programs. Also it is very important to bring up manpower competent for these projects.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 제16회 생물과학 심포지움 강연록
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• pp.68-73
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• 1995

Most female Great Tits lay one egg each day until the clutch is complete. However, some exceptions are found. “Pause day/s” most frequently occur after the 1st egg is laid. In general, egg-size increase with laying sequence, but there is year-to-year variation. The relationship between egg size and laying sequence is found more significantly in relatively larger clutches than in smaller ones. Great Tits tend to advance the hatching of their chicks by starting to incubate earlier in relation to clutch completion as the breeding season progresses. hatching asynchrony affects chick´s growth rate, but when the effect of laying date on hatching asynchrony is controlled, the effect of hatching asynchrony on growth rate is not found. These findings support the ´hurry-up´ hypothesis.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.165-170
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• 2009

The Korean high-speed rail network has been made a remarkable growth recording the world's 4th rank passenger transportation scale during last 5 years after opening the revenue service of Kyoung-bu high-speed line in 2004. However, in spite of it's outstanding growth, Korean Rail technology should meet a demand of intensive technology development in order to prepare a severe competition with an advance parties of worldwide high-speed rail technology. In this paper, the characteristics and new trend of world's rail industry was reviewed based on the most recent statistics and papers of worldwide rail network from UIC and WCR32008. In conclusion, new R&D strategy with choice an concentration for the Korean high-speed rail industry was suggested based on an analysis on the trend of evolution of the state of the art technologies in worldwide high-speed rail system.

• 한국산림과학회지
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• 제94권4호통권161호
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• pp.264-268
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• 2005

참나무류 임분에 자연 발생한 잣나무와 인공 조림된 잣나무 침엽을 80% acetone과 DMSO(Dimethylsulfoxide)로 추출하여 측정한 엽록소 함량을 비교하였다. 80% acetone에 비해 DMSO로 추출한 총 엽록소 함량은 잣나무 침엽의 모든 연령에서 약 4-6배 높은 값을 나타했다. 또한 DMSO로 추출한 경우 상층 임관을 점유한 인공 조림된 잣나무와 하층에 생육하는 잣나무 간에는 총 엽록소 함량에 차이가 없었으며, 80% acetone으로 추출한 경우에도 역시 두 종류의 잣나무 사이에 연령별 총 엽록소 함량의 차이는 없었다. DMSO로 추출할 경우 자연 발생 잣나무와 인공 조림된 잣나무 침엽 모두 6시간의 추출이 적절한 것으로 판단된다.