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101.
近年来我国原油进口数量急剧增加。石油安全问题引起广泛关注。而我国煤炭与天然气资源相对比较丰富。统筹规划并合理利用煤、油、气资源,通过煤化工、石油炼制、石油化工3个行业技术上的互相借鉴,资源上的互相替代,产业链的互相补充,尽量减少石油的消耗,以减轻对进口原油的依赖。  相似文献   
102.
某燃气公司一段埋地高压天然气输送管线某处发生严重破损,为分析失效原因,作者采用宏观形貌分析、扫描电镜分析、化学成分分析、显微组织分析、力学性能检验、Fluent模拟分析等系列方法对该失效管段进行分析。结果表明,与该天然气管近距离平行铺设的自来水供水管道破裂,导致高速水流正面与切向冲刷作用,最终导致天然气管破裂。根据分析结论,提出了预防同类事故发生的建议。  相似文献   
103.
文章构建VAR模型和CAPM-GARCH模型,分析检验了2010年7月初至2013年底期间传统能源和碳排放权交易价格对国内新能源上市公司股价波动的影响及新能源股票收益率的波动特点,研究发现:国内煤价对新能源公司股价有显著的正向影响,而国际油价的影响不显著;碳排放权交易价格也是引起新能源投资价值从而上市公司股价变动的重要因素;新能源公司股价指数对高科技股价指数并不敏感,反映出国内新能源上市公司科技含量不足,资本市场关注更多的是新能源的概念而非技术优势;国内新能源股票整体的系统风险在1.125~1.131之间,利好消息比利空消息能引起新能源股票收益率更大的波动。  相似文献   
104.
Common definitions of ecotourism address the need to benefit the well-being of local people; in reality, ecotourism is often supported or dominated by external agents. Local ideological, social and cultural values may be overlooked, thereby disenfranchising local and indigenous stakeholders. This paper examines indigenous perceptions of ecotourism and well-being, and how they relate to ecotourism practices in three Brokpa communities of the first protected area in Bhutan to become a special tourism destination. A range of methods (e.g. semi-structured interviews, participatory mapping) was used and data analysis was couched in the context of buen vivir (living well), an indigenous concept of well-being. Findings indicate that: (1) perceptions of ecotourism vary between community members and contrast with the official park definition; (2) well-being is conceived in diverse ways but corresponds to key features of buen vivir; (3) indigenous worldviews are pervasive, and shape social values and spiritual beliefs in connection to nature; and (4) indigenous cosmologies and traditional values may be strengthened through their integration into modern policies and institutions. This research contributes more non-Western voices to the literature, a concept and mode of analysis for well-being that embraces an indigenous ontology, and empirical insights on indigenous communities in protected areas.  相似文献   
105.
重推原油期货对我国的影响及完善建议   总被引:1,自引:0,他引:1  
摘要:中国重新推出原油期货,是经济发展的必然结果。目前原油期货上市意义重大,上市时机已经成熟。重推原油期货,需要:打破石油市场的垄断,吸引广泛的市场参与主体;建立更具开放性、操作性的交易机制;建立并完善石油战略储备体系;大力发展资本市场,构建多层次金融市场体系,推进石油金融一体化;多视角择机推动“石油人民币”体系的建立,促进人民币的崛起。  相似文献   
106.
以北部湾城市群为例用三维生态足迹模型、偏最小二乘法、空间计量模型分析了其自然资本利用状况、空间相关性、驱动因素。结论:(1)城市群自然资本利用处于不可持续状态;(2)自然资本利用程度划分为低、中、高三类,城市也相应分成三类;(3)自然资本利用的主要驱动因素是人口因素、社会经济;(4)空间分析显示全局莫兰指数为正,空间集聚显著,表明自然资本利用存在空间正相关;空间误差模型拟合度最好,并证明自然资本存量占用与人口总量正相关,与GDP总额负相关。  相似文献   
107.
刘爱宁 《价值工程》2014,(19):73-74
本文针对石油天然气工程造价管理以及所存在的问题进行探究。  相似文献   
108.
109.
In the 1990s, the Democratic People’s Republic of Korea (North Korea) suffered from severe food shortages and large-scale deforestation, which triggered a stage of rural conservation reform. Since 2004, with support from the Swiss Agency for Development and Cooperation (SDC), North Korea’s Ministry of Land and Environmental Protection (MoLEP) has implemented a Sloping Land Management Program (SLMP). The SLMP established sloping land user groups and granted these groups the right to use marginal land for agroforestry development. This devolution of land rights from state control onto local groups is a landmark in North Korea, and this decentralization initiative has now expanded to over eight counties to involve thousands of households. It has also led to the launch of a National Agroforestry Policy and Strategy. Drawing from both qualitative and quantitative data collected from 2008 to 2014, this paper documents the process and effects of the SLMP. It argues that the decentralization reform in land management has contributed to not only food security with increased food crop diversity and productivity, but also notably forest recovery through an expansion of tree plantations and agroforestry practices on degraded sloping lands. However, an insufficient power transfer in the form of a lack of timber rights granted to the local user groups has hampered the effectiveness of the SLMP. There are also institutional and geopolitical challenges that are limiting further scaling-up of land-use decentralization across the country. The policy implication calls for more international investment as well as national land-use policy reforms in order to promote and facilitate further decentralization of sloping land management and to secure greater use rights for sloping land user groups.  相似文献   
110.
The European Commission follows a harmonized approach for calculating structural (potential) output for EU member states that takes into account labour as an important ingredient. This article shows how the recent huge migrants’ inflow to Europe affects trend output. Due to the fact that the immigrants immediately increase the working population but effectively do not enter the labour market, we illustrate that the potential output is potentially upward biased without any corrections. Taking Germany as an example, we find that the average medium-term potential growth rate is lower if the migration flow is modelled adequately compared to results based on the unadjusted European Commission procedure.  相似文献   
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