• 한국경제지리학회지
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• 제11권1호
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• pp.130-147
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• 2008

1770년대에 스페인의 선교사들이 캘리포니아에서 종교적 의식에 사용할 목적으로 포도를 재배하고 포도주를 생산하기 시작했고, 그로부터 100년이 지난 후 캘리포니아에서 상업적 목적의 포도주 생산이 시작되었다. 미국은 이제 프랑스, 이탈리아, 호주 다음 가는 포도주 생산국이 되었으며, 캘리포니아는 미국 포도주 생산의 95%를 차지하게 되었다. 또한 캘리포니아 포도재배 및 포도주 생산기술은 1970년대 초반부터 세계적인 수준에 이르렀음이 확인되었다. 이러한 캘리포니아 포도주 생산의 중심에는 나파와 소노마가 있다. 나파와 소노마에는 포도재배 및 포도주 생산, 그리고 와인투어 등, 1차, 2차, 3차 산업을 통합하는 의미 있는 와인산업 클러스터가 조성되어 있다. 본 연구는 지역혁신체제론에 입각한 분석틀에 기초하여 나파와 소노마의 와인산업 클러스터의 성장과정과 혁신주체, 그리고 그들이 형성하고 있는 거버넌스를 규명하고, 정책적 시사점을 도출한다.

• 플랜트 저널
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• 제7권2호
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• pp.44-51
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• 2011

Given the fact that the entire bituminous coal used for a boiler is imported, the supply of coal is often affected by the rise of international coal price. Moreover, coal suppliers have been diversified due to the competition among power generation companies for reducing costs and inexpensive sub-bituminous coal is used. As a result, boilers combustion conditions have been deviated from the initial boiler design. This requires the selection of adequate excessive air ratio for different combustion conditions to enhance the efficiency of boiler operation. The boiler efficiency has been identified through an examination on the change of excessive air ratio by mixed fuel in unit 8 of Dangjin power plant complex. In addition, an excessive air ratio was calculated based on the examination result. According to the study result, the adequate excessive air ratio was 13% when Macquarie and Powder river were mixed at a ratio of 5:5 and when Sonoma and Megaprima persada were mixed at a ratio of 5:5. When BHP Billiton and Powder river were mixed at a ratio of 4:6 and Centennial and Batubara were mixed at a ratio of 3:7, the adequate excessive air ratio was 11%.

• 플랜트 저널
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• 제6권2호
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• pp.70-77
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• 2010

This study investigated the characteristics of co-combustion of mixed anthracite (domestic and Vietnam) and bituminous coal (Sonoma, Australia) at circulating fluidized bed boiler in Donghae thermal power plant when mixing ratio of bituminous coal is variable. Co-combustion of bituminous coal contributes to improvement in general combustion characteristics such as moderately retaining temperature of furnace and recycle loop, reducing unburned carbon powder, and reducing discharge concentration of NOx and limestone supply owing to improvement in anthracite combustibility as the mixing ratio was increased. However, bed materials were needed to be added externally when the mixing ratio exceeded 40% because of reduction in generating bed materials based on reduction in ash production. When co-combustion was conducted in the section of 40 to 60% in the mixing ratio while the supplied particles of bituminous coal was increased from 6 mm to 10 mm, continuous operation was shown to be possible with upper differential pressure of 100 mmH2O (0.98 kPa) and more without addition of bed materials for the co-combustion of mixed anthracite and bituminous coal (to 50% or less of the ratio) and that of domestic coal and bituminous coal (to 60% of the ratio).