• 제목/요약/키워드: Reserves

검색결과 489건 처리시간 0.028초

Bauxite developments in Vietnam : Opportunities and Challenges

  • Lai, Quang Tuan;Ahn, Ji Whan
    • 에너지공학
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    • 제27권3호
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    • pp.41-47
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    • 2018
  • Bauxite is the principal raw material to produce alumina. Bauxite mining industry has grown gradually due to the rising demand for alumina. U.S Geological Surveys (USGS 2018) estimates the world's reserves of bauxite roughly 55-75 billion tonnes. Vietnam holds up to 3.7 billion tonnes, the third after Guinea and Australia. Most of bauxite reserves are located in Tay Nguyen (Central Highlands), and have only been minimally mined to date. The approved master plan in 2007 of the Government of Vietnam licenses bauxite mining and alumina production projects in Central Highlands through six projects until 2025. These projects constitute many potentially enormous economic, social and environmental impacts.

고추종자의 성숙에 따른 구조 및 저장물질의 전자현미경적 연구 (Electron Microscopic Study of Structures and Storage Reserves in Capsicum annuum Seeds)

  • 김세규;김은수;김우갑;이광웅
    • Applied Microscopy
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    • 제25권4호
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    • pp.71-82
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    • 1995
  • The ultrastructure and storage reserves of the Capsicum annuum seeds were studied in order to identify structure and to localize storage components in the endosperm using light microscopy, scanning and transmission electron microscopy. The seed coat was composed of one cell layer which contained a large number of lipid bodies, while most of the endosperm cells did not showed many lipid bodies. During seed maturation, the endosperm cells were continuously degenerated by the autophagy. Various types of plastids were also distinguished in the endosperm cells. They contained starch grains surrounded by electron-dense tiny particles, plastoglobuli, and vasicular bodies.

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Review on Research and Development of Shale Gas in China

  • Zhuang, Li;Kim, Kwang Yeom;Sun, Zhi-xue;Li, Yan-chao
    • 지질공학
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    • 제25권3호
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    • pp.323-329
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    • 2015
  • Shale gas reserves in China are large, although shale gas production is still in its infancy. This paper reviews Chinese national policies and guidelines related to shale gas development, in particular those related to recent progress in the development of shale gas reserves in Sichuan Province and Chongqing since February 2015. In addition, three large-scale R&D projects related to shale gas development, funded by the Government of China, are introduced, and the scope of the work in each project is described.

제철플랜트용 석탄건조설비에서 운전조건 변경이 건조성능에 미치는 영향 (Effect of Operating Conditions on Drying Efficiency for Coal Drying Facilities in a Steel Making Plant)

  • 전해석;문승재;유호선
    • 플랜트 저널
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    • 제5권4호
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    • pp.73-79
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    • 2009
  • Increase of consumption in limited coal reserves leads prices surging. As a result, iron works which produce products with coal are in difficulties. Accordingly, it is required a lot of research of using non-caking coal that is relatively low cost and has abundant reserves. Direct drying and indirect drying are two major methods of drying the coal. Recently, to minimize the needed calories and to save energy, using fluidbed or fluidizing method is a recent main trend of minimizing the size of the facility and maximizing energy efficiency. However there is also disadvantage such as increasing facility investment because of installing additional facilities in the latter part. In this study, we will have theoretical researches on the indirect drying method with heat exchange system which have been traditionally used. As a result it is expected to increase the efficiency of the facility operation.

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Survey Effects of Oil Income on Nonoil Export and Effort for Decline in Dependence to Oil Income

  • Varahrami, Vida
    • 동아시아경상학회지
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    • 제4권4호
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    • pp.21-23
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    • 2016
  • There are so much oil and gas reserves in Iran. Therefore extraction from these reserves and sell extracted oil and gas in international markets causes to high oil income for Iran. Especially in some years which oil price increases, our oil income was too high. In this paper, we want to reveal that, high oil income is not cause to rise of nonoil export. For this aim, we use from data of 1971-2013 and with Johansen co-integration test and Error Correction Model (ECM) extract short run and long run relations. Results of estimation reveal that in Iran high oil income is not cause to many non oil exports in long run and short run. Therefore, we should allocate oil income to import industrial machines and reallocate them to agriculture and industrial sectors which causes to raise national production which will cause to high non oil export. Then, in this condition, our needy exchanges are provided from non oil export and our dependence to oil income will be declined.

우리나라 계통의 전압제어지역별 무효전력 예비율 산정 (The estimation of reactive power reserves of generators in voltage control areas of KEPCO systems)

  • 김봉식;최윤혁;서상수;이병준;이흥재;송인준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.455-456
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    • 2007
  • Maintaining the voltages is important in the power systems and the voltage is closely associated with the reactive powers. Therefore, the voltages are maintained by controlling the reactive powers. However actually it is impossible to control reactive power for maintaining all bus voltages. Thus, Secondary Voltage Regulation was designed. It divides power systems into some control areas and controls pilot node with the included generators. The reactive powers of generators can control pilot bus voltage continuously and fast. Therefore we need to divide areas and select control generators for SVR with Electrical distance. Then estimation of the reactive power reserves of geneators is needed in voltage control areas to control voltages of the pilot nodes.

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