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61.
矿井工作面瓦斯超限严重影响着矿井安全生产和生产效率,现用解决该问题的方法存在局限性,不能广泛适用于所有矿井。针对该问题,采用水及含添加剂水阻碍和延缓煤体内瓦斯解吸速度,以达到降低工作面瓦斯涌出量的目的。本文通过对其抑制原理相关研究的介绍,为同类工作面瓦斯超限治理提供基础理论依据。 相似文献
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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
65.
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
66.
针对采气工在生产工作中所处的工作环境,分析了其对人体的7个部位可能造成的伤害,提出了"配置到站"与"配置到人"两种配置模式,从标准的适应性和经济性进行了分析,并提出了相应的劳动防护用品配置标准的改进建议。 相似文献
67.
徐伊岑 《无锡商业职业技术学院学报》2014,(3):106-108
为了在实验室中计量厌氧发酵时产生的沼气体积,设计了一种便携式气体体积计量系统,并分析了系统的构成及运行流程,给出了主要硬件及软件设计方法。试验结果表明,该系统结构合理,使用方便,满足实验室测量气体体积的需要。 相似文献
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We examine natural disasters and long‐run climatic factors as potential determinants of international migration, implementing a panel dataset of bilateral migration flows from 1960 to 2000. We find no direct effect of long‐run climatic factors on international migration across our entire sample. These results are robust when conditioning on origin‐country characteristics, when considering migrants returning home, and when accounting for the potential endogeneity of migrant networks. Rather, we find evidence of indirect effects of environmental factors operating through wages. We find that epidemics and miscellaneous incidents spur international migration, and there is strong evidence that natural disasters beget greater flows of migrants to urban environs. 相似文献
70.
对与油气管道领域相关的ISO、API、ASME、ASTM、NACE 5所知名国外标准化组织进行了简要介绍,对各组织在提案申请要求、提案内容、尤其是标准制修订流程方面进行了初步对比分析,同时以参与国际标准化组织ISO,为例详细说明了参与国际标准的注意事项及技巧,最后提出了我国在油气管道领域开展标准国际化的启示和建议。 相似文献