遥感估算绿洲-沙漠下垫面地表温度及感热通量     

王丽娟  左洪超  陈继伟  董龙翔  赵静 《高原气象》2012,31(3):646-656

利用古浪非均匀近地层野外观测试验资料,验证了卫星反演地表温度的局地分裂窗算法在非均匀地区的适用性,进一步给出了提高反演精度的修正方案,并利用修正的反演地表温度算法和改进的空气动力学阻抗算法反演了试验区的感热通量。结果表明,Becker算法最适用于非均匀地区。与近地层野外观测试验观测结果相比,修正后的反演算法反演的地表温度和感热通量更加合理,均方根误差分别为2.38K和23.49W.m-2。地表温度和感热通量的区域分布特征相似,都表现为在绿洲和沙漠区的变化梯度较小,而在过渡区的梯度较大。  相似文献   

东营凹陷南坡成藏期油气运移动力与阻力耦合关系:以金8—滨188剖面为例   总被引：1，自引：1，他引：0  

高永进  王永诗  于永利  姜振学  田苗  渠冬芳  李晓蕾 《现代地质》2010,24(6)

以东营凹陷西部的金8—滨188剖面为研究对象,应用过程约束的盆地模拟方法恢复关键成藏期油气成藏动力演化史。通过建立储层物性恢复图版的方法恢复储层古物性,进而求得储层关键成藏期的毛细管阻力并恢复了以其作为成藏阻力的演化史;通过油气成藏动力与阻力进行耦合,获取了成藏动力梯度的演化史;利用成藏动力梯度演化史和已发现油气藏的关系预测有利成藏区带。金8—滨188剖面缓坡带的滩坝砂成藏条件最好,为Ⅰ类有利部位,坡底浊积岩透镜体和缓坡带的三角洲为Ⅱ类有利部位,坡底的滩坝砂为Ⅲ类有利部位。  相似文献   

Radial consolidation with variable compressibility and permeability following pile installation     

Jun-Jie Zheng  Yan-Er Lu  Jian-Hua Yin  Jia Guo 《Computers and Geotechnics》2010

The excess pore pressure generated by pile installation gradually dissipates following installation, which mainly dominates the increase of pile capacity with time. The dissipation of the excess pore pressure following pile installation has been widely investigated by experimental and theoretical studies. However, in most research, the consolidation coefficients were assumed to be constant for simplification, which may lead to errors. In the present study, the dissipation of the excess pore pressure is analyzed by radial consolidation theory with a variable consolidation coefficient based on the linear responses of e − ln(p^′) and e − log(k). The governing equation of the radial consolidation considering variable compressibility and permeability are solved by the variable separation method. Bessel functions are used to solve the differential functions for the time independent part. The excess pore pressure immediately after pile installation is obtained from cavity expansion theory and is used as the initial condition of the consolidation process. Moreover, the influences of variable compressibility and permeability on the variation of consolidation coefficient and excess pore pressure dissipation are analyzed.  相似文献   

基于结构两相阻力分析的泥石流堆积形态研究   总被引：1，自引：0，他引：1  

樊赟赟  王思敬  王恩志 《工程地质学报》2010,18(1):100

针对泥石流的结构两相阻力特征,采用结构两相阻力对泥石流的堆积形态进行了静力学分析,推导出在一般条件下泥石流堆积形态的公式,并讨论了在不同条件下泥石流堆积形态的特点。分析表明采用结构两相阻力对泥石流堆积形态分析可以较合理的模化阻力项,能够表现泥石流体复杂的成分结构组成,较真实的反映实际泥石流的堆积形态特征。在特定材料条件下,结构两相阻力项转化为单一材料阻力项,所得到的相应结论与已有对单一材料的分析结论一致。  相似文献   

云南玉溪抗旱找水定井典型实例分析与感悟     

程秀明  林海  姜春永  赵玉祥  宋希利  罗斐 《上海国土资源》2010,31(Z1)

西南大旱百年不遇,山东找水专家组紧急驰援云南抗旱。通过对云南抗旱找水定井实例的分析,总结了高原岩溶水和红层基岩裂隙水的找水勘察工作思路,并联系云南、四川、山东等贫水区找水定井实践,阐述了贫水区找水定井心得与感悟。  相似文献   

秋季在北京城郊草地下垫面上的一次臭氧干沉降观测试验   总被引：3，自引：0，他引：3  

潘小乐  王自发  王喜全 《大气科学》2010,34(1):120-130

2007年9月23日至10月13日, 在北京昌平区蟒山森林公园内, 利用浓度梯度观测法研究了秋季草地下垫面上臭氧的干沉降特征。研究结果表明: (1) 整个观测期间, 臭氧干沉降通量和干沉降速率平均值分别为-0.40 μg?m-2?s-1(负号表示方向指向地面) 和0.55 cm/s。 (2) 臭氧干沉降通量和干沉降速率受观测点山谷风的影响, 当白天谷风主导时, 臭氧的干沉降通量最大, 其平均值为－0.67 μg?m-2?s-1; 在山风、 谷风转换期间, 其平均值为－0.44 μg?m-2?s-1; 夜间山风主导时最小, 为－0.26 μg?m-2?s-1。臭氧干沉降速率也呈现同样的变化规律, 三种情形下的平均沉降速率分别为0.74 cm/s、 0.50 cm/s和0.47 cm/s。 (3) 利用阻力模型计算了臭氧的植被冠层阻力 (Rc), 结果表明: 由于白天植被的光合作用, 叶面气孔打开, 冠层阻力相对较小, Rc 的平均值为109.0 s/m; 夜间植被叶面气孔关闭, 阻力有明显升高, Rc的平均值为217.7 s/m; 在整个观测期间, Rc的平均值为184.0 s/m。  相似文献   

附加相位延迟到弯曲角反演过程中的误差传递模型   总被引：1，自引：0，他引：1  

王也英  符养  杜晓勇  严卫 《气象学报》2010,68(4):514-519

为了研究全球卫星导航定位系统无线电掩星探测中的误差传递过程,文中讨论了掩星探测中附加相位延迟到弯曲角的反演过程中,附加相位延迟随机误差对反演弯曲角误差的影响。在对全球卫星导航定位系统和低轨道卫星进行精密定轨的情况下,忽略轨道误差对反演结果的影响,将轨道参数视为常数,考虑附加相位延迟△L存在随机误差δ△L时对反演弯曲角α带来的弯曲角误差δα。利用EGOPS仿真软件,采用数值模拟的方法模拟了无电离层影响的大气附加相位延迟数据,利用CHAMP真实轨道数据,MSIS-90大气模型和全三维射线追踪器进行前向建模,从中选取了一个掩星事件对误差传递模型进行了验证。结果表明:附加相位延迟的变化会给弯曲角的反演带来相应的误差:当随机误差为5 cm左右时,反演的弯曲角误差在±0.2 mrad范围内;当随机误差为1 cm左右时,反演的弯曲角误差在±4μrad范围内;当随机误差为1 mm左右时,反演的弯曲角误差在±40μrad范围内。最后从模拟的掩星事件中随机抽取了20个掩星事件进行统计分析,给出了20个掩星事件存在1 cm附加相位延迟测量误差引起弯曲角误差的均值误差,其误差特性虽略大于个例研究结果,但与模型完全吻合,反演的弯曲角误差也在±40μrad范围内,进一步验证了模型的准确性。  相似文献   

Spatial variation of cone tip resistance for the clay site at Texas A&M University     

Pinnaduwa H. S. W. Kulatilake  Jeong-Gi Um 《Geotechnical and Geological Engineering》2003,21(2):149-165

The cone tip resistance data available for the clay site at Texas A&M University, USA (one of the National Geotechnical Experimentation Sites) are used to show how the spatial variation of a soil property can be quantified. It is suggested that the first step in quantifying the spatial variation of a soil property should be the identification or selection of the statistically homogeneous soil layers. A new simple procedure is suggested to identify statistically homogeneous layers in a soil profile. Through examples it is shown that the procedure works extremely well in identifying the statistically homogeneous layers. For the chosen statistically homogeneous layers, the spatial variation of cone tip resistance with depth is quantified in terms of a constant mean or a mean trend, variance/standard deviation/coefficient of variation or a variance around the mean trend, and a correlation or variogram function. Correlation distances in the depth direction were found to be between 0.1 and 0.5m for the two soil layers investigated. It was shown that the correlation distance decreases in the presence of a global mean trend for the soil property. In such cases, it is important to note that a part of the correlation is automatically included in the mean trend function.  相似文献   

降低高原地震台仪器设备接地电阻的技术措施   总被引：1，自引：0，他引：1  

刘建明 《四川地震》2006,(2):40-42

良好的接地条件是地震台仪器设备正常工作的基本保证。通过对四川省部分高原地震台仪器、设备一般接地装置的技术性能、接地材料、改进及维护等方面进行总结之后,提出了改善接地条件的几项有效措拖:(1)保证构架接地体部位有良好的焊接质量;(2)更换接地线的掩埋土壤;(3)在掩埋土壤中添加降阻材料;(4)后续使用中灌水改善引线接地条件。  相似文献   

Integrated Community-Based Disaster Management Program in Taiwan: A Case Study of Shang-An Village     

Liang-Chun Chen  Yi-Chung Liu  Kuei-Chi Chan 《Natural Hazards》2006,37(1-2):209-223

Taiwan has long made efforts to increase community emergency response capability, due to its vulnerability to earthquakes, typhoons, landslides and debris flows. Not until recent major natural disasters, such as the 1999 Chi–Chi Earthquake, Typhoon Toraji and Typhoon Nari, has the government reformed its policy toward empowering the community to take actions in hazard mitigation, emergency preparedness and emergency response. A new initiatve, Integrated Community-Based Disaster Management Program (ICBDM), was launched in 2001 by the Executive Yuan to achieve the goal of strengthening community resistance. The paper, taking Shang-An Village as an example, describes Taiwan’s new community-based disaster management program. Through a participatory process, community residents have learned how to analyze vulnerable conditions, discover problems, develop solutions and establish an organization to implement disaster management tasks. Further, basic response training courses and a disaster scenario were held in order to improve their emergency response capability. Based on the case study, a phased process, including initiation, assessment, planning and practice, is generalized.  相似文献