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关于两相饱和介质中流相Green函数的解析解   总被引:3,自引:0,他引:3       下载免费PDF全文
自然界中许多动力学问题需要用两相饱和介质Green函数求得解答,本文在两相饱和介质位移场Green函数解答的基础上,求得的有关饱和流体孔隙压力,进、排流体流量等三个Green函数.从而使两相饱和介质涉及流体问题的Lamb方程能完整地使用.论文在推导过程中详细地阐述了流体三个Green函数的物理意义,并将所得结果与Chen(1994)的纯数学的结果作了对比.最后文章讨论了解析解的稳定性.  相似文献   
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Recent investigations have derived the relation between the near-field plane amplitude and the surface deformation of reflector antenna,namely deformation-ampli...  相似文献   
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He  Jia  Yang  Feng  Qi  Yong-Shuai  Fang  Chang-Hang  Yan  Bo-Yang  Zhang  Yi  Hang  Lei  Gao  Yu-Feng 《Acta Geotechnica》2022,17(7):2895-2905
Acta Geotechnica - Enzyme-induced carbonate precipitation (EICP) is a promising method for the improvement in soil properties. In this study, a model test using a meter-scale soil model was carried...  相似文献   
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Yang  Xiao-Hua  Sun  Bo-Yang  Zhang  Jian  Li  Mei-Shui  He  Jun  Wei  Yi-Ming  Li  Yu-Qi 《Natural Hazards》2015,76(1):63-81

Rapid population growth and increased economic activity impose an urgent challenge on the sustainability of water resources in Beijing. Water resources system is a complex uncertain system under climate change which is of vulnerability. But water resources system vulnerability research is relatively weak. In this study, we present a multifunctional hierarchy indicator system for the performance evaluation of water resources vulnerability (WRV) under climate change. We established an evaluation model, i.e., analytic hierarchy process combining set pair analysis (AHPSPA) model, for assessing WRV, in which weight is determined by the analytic hierarchy process (AHP) method and the evaluation degrees are determined by the set pair analysis (SPA) theory. According to the principle of scientificalness, representative, completeness and operability, the index systems and standard of water resources vulnerability evaluation are established based on the analysis of sensibility and adaptability which include five subsystems: climate change, water resources change, social and economic infrastructure, water use level and water security capability. The AHPSPA model is used to assess water resource vulnerability in Beijing with 26 indexes under eight kinds of future climate change scenarios. Certain and uncertain information quantity of the WRV is calculated by connection numbers in the AHPSPA model. Results show that the WRV of Beijing is in the middle vulnerability (3 or III) under above-mentioned different climate change scenarios. The uncertain information is between 37.77 and 39.99 % in the WRV evaluation system in Beijing. Compared with present situation, the WRV will become better under scenario I and III and will become worse under scenario II, scenario IV, scenario representative concentration pathways (RCP)2.6, scenario RCP4.5, scenario RCP6.0 and scenario RCP8.5. In addition, we find that water resources change and water use level factors play more important role in the evaluation system of water resource vulnerability in Beijing. Finally, we make some suggestions for water resources management of Beijing.

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根据时统IRIG B(简称“B码”)的码形特点和编码原理 ,介绍利用计算机普通声卡接收标准化时统设备B码信号的硬件工作机理 ,着重阐述了软件解码的实现过程和为计算机提供标准时间的方法。  相似文献   
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融合多源数据的高精度、高分辨率的局部重力场建模是物理大地测量学的前沿和热点问题.本文研究了基于径向基函数融合多源数据的局部重力场建模方法,利用Monte-Carlo方差分量估计实现了不同类型的观测数据的合理定权,引入了最小标准差法确定基函数的适宜网络,分析了地形因素对于基函数网络确定及局部重力场建模精度的影响.以泊松小波基函数为构造基函数,结合残差地形模型,融合实测的陆地重力异常、船载重力异常及航空重力扰动数据构建了局部区域陆海统一的似大地水准面模型.研究结果表明:引入残差地形模型平滑了地形质量引入的高频扰动信号,简化了基函数的网络设计;并提高了重力似大地水准面的精度,平原地区其精度提高了4mm,地形起伏较大的山区其精度提高了约5cm.总体而言,基于"三步法"构建的局部重力似大地水准面在荷兰、比利时及德国相关区域,其精度分别达到1.12cm、2.80cm以及2.92cm.  相似文献   
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