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21.
AbstractIn 2011 a wave of revolutionary movements, the so-called Arab Spring, spread in the Middle East and North Africa. Libya was one of the most affected countries, ending Gaddafi’s dictatorship after an international intervention and a civil war. This paper assesses the effects that this revolution had on Libyan economy. The analysis is made by means of the synthetic control method. Our estimates for the 2011–2014 period show (i) a cumulative loss in the growth rate of per capita real GDP of 64.15%; (ii) a cumulative loss in per capita real GDP of 56,548 dollars; and (iii) a cumulative loss in the aggregate real GDP of 350.5 billion dollars. 相似文献
22.
重庆市奉节县挖断村滑坡规模巨大,滑坡体长180~250m,滑坡体厚15~35m,剩余下滑力达5 337 kN/m,采用了前排全长后排埋入式的新型组合抗滑支挡技术,大大节省了工程投资。介绍了这种新型组合抗滑结构的设计方法,重点介绍了桩的长度计算、各桩承担滑坡推力计算、治理后的监测数据。工程竣工2年的监测数据表明滑坡变形趋于稳定,说明采用全长和埋入式组合抗滑桩治理该滑坡是有效的。 相似文献
23.
何涛 《武警工程学院学报》2014,(4):51-54
运用心理学的有关知识,结合军事训练的内容、特点和方法,认真总结了军事技能教学训练中受训者易出现的多种心理障碍,深入分析了其产生的原因,并结合教学经验,探讨科学的治疗对策,为预防及解决军事训练心理障碍问题提供参考,为提高部队军事训练质量提供保障。 相似文献
24.
《防务技术》2014,10(1):1-8
This paper reports the effects of post weld heat treatments, namely artificial ageing and solution treatment followed by artificial ageing, on microstructure and mechanical properties of 12 mm thick friction stir welded joints of precipitation hardenable high strength armour grade AA7075-T651 aluminium alloy. The tensile properties, such as yield strength, tensile strength, elongation and notch tensile strength, are evaluated and correlated with the microhardness and microstructural features. The scanning electron microscope is used to characterie the fracture surfaces. The solution treatment followed by ageing heat treatment cycle is found to be marginally beneficial in improving the tensile properties of friction stir welds of AA7075-T651 aluminium alloy. 相似文献
25.
古建筑防火新技术研究 总被引：1，自引：0，他引：1
阐述了古建筑火灾的危险性,并从本质安全的角度研究了古建筑中木材、纤维织物的阻燃措施。指出木材的阻燃处理方法通常采用物理和化学方法,而化学方法可采用表面涂覆、浸渍处理、化学改性三种方法;纤维织物阻燃处理采用共聚阻燃改性、共混阻燃改性、阻燃后整理、接枝共聚、皮芯型复合纺丝等方法。可以根据具体情况选用合适的阻燃处理方法,从而达到降低材料可燃性的目的,大大提高古建筑的火灾风险等级。 相似文献
26.
制退机的性能好坏直接关系到火炮作战效能的发挥。针对目前装备保障方式大多停留在维修层面而理论研究不够深入的实际,对节制环磨损故障的机理进行分析。以某型火炮短节制杆式制退复进机为对象,利用MATLAB数值计算平台,编程仿真节制环磨损故障对后坐的影响。同时探讨了故障后对火炮的处理方案。研究表明,节制环磨损对后坐诸元都将产生不同影响,针对影响的程度可制定相应的故障处理方案。仿真模拟和方案探讨对装备保障工作具有参考意义。 相似文献
27.
We consider a design problem for wastewater treatment systems that considers uncertainty in pollutant concentration levels at water sources. The goal is to optimize the selection of treatment technologies and pipeline connections, so that treated wastewater can achieve specified effluents discharge limits as well as possible. We propose a new two-stage model to optimize a set of guarantee levels, that is, the maximum concentration level of source pollutants for which treated wastewater can be compliant with discharge limits. In the first stage, treatment technologies and pipeline connections are selected. In the second stage, when pollutant concentration levels are revealed, wastewater distribution and mixing are determined. A key attractiveness of the proposed guarantee rate optimization model is that it can be simplified into a single-stage mixed-integer linear program. In our numerical experiments based on real-world pollutants data, the guarantee rate model demonstrates its advantages in terms of computational efficiency, scalability and solution quality, compared with the standard probability maximization model. Finally, the methodology proposed in this paper can also be applied to other two-stage problems under uncertainty with similar uncertainty characteristics. 相似文献
28.
卢新焵 《国防科技大学学报》1988,10(4):85-91 ，119
文中研究了临界点间热处理对Welten-80p钢、20CrMnSi钢及20CrmnSiNi2A钢低温韧性的影响。结果表明:与常规热处理相比,临界点间淬火及回火钢的a_k值提高了1～3倍,冷脆转变温度降低了54℃。临界点间热处理是提高结构钢低温韧性的有效措施。 相似文献
29.
聚类方法在污水处理软测量中的应用机理研究 总被引：1，自引：0，他引：1
通过对污水处理过程建立多神经网络模型的可行性研究以及对活性污泥微生物的生长繁殖规律分析,得出在污水处理工程中采用基于聚类方法的多神经网络建模的理论依据,试验表明多神经网络的扩散常数同类半径相当接近,预测精度较高,证实了聚类分析的正确性.分析了可能影响模型精度的原因,指出采用在线实时算法是未来的研究方向. 相似文献
30.
合同制消防队伍建设发展探索 总被引：1，自引：0，他引：1
简述了我国合同制消防队伍的现状,全面总结了目前我国合同制消防队伍存在的问题,深刻分析了阻碍合同制消防队伍稳定发展的主要因素,并重点提出了针对性的改进措施,为我国合同制消防队伍健康有序发展提供了有益借鉴。 相似文献