重力固体潮理论值导数的封闭公式   总被引：3，自引：1，他引：2       下载免费PDF全文

苏其辉  黄其明 《地球物理学报》1994,37(5):647-652

本文基于计算重力固体潮理论值的天顶距法，通过严格的理论推导，给出了计算重力固体潮理论值的导数的封闭公式．  相似文献   

Practical applicability of high frequency correction theories to CO<Subscript>2</Subscript> flux measured by a closed-path system     

Takanori Shimizu 《Boundary-Layer Meteorology》2007,122(2):417-438

The theoretical correction of CO₂ fluxes for high frequency attenuation in closed-path systems was re-summarized and its applicability examined using both measurements obtained at an Asiaflux forest site and empirical transfer functions used in previous studies. For our measurement system, the theoretical transfer function was applicable to high frequency correction, even when condensation occurred in the sampling line. Further, in respect to some measurement systems described in previous studies, it was found that the theoretical function was potentially applicable along with the empirical functions used. Meanwhile, in some systems significant errors could not be resolved by re-estimation of the theories. In these systems, because of undefined buffering effects, the actual response lag time decided by the maximum covariance method or by measurement of the system response time using tracer gas was significantly different from the lag time calculated from the tube dimensions and the measured flow rate. If the average flow rate calculated by the actual lag time was used to determine the theoretical function, the theoretical function became closer to, and sometimes agreed with, the empirical function. Any remaining deviation from each function might be associated with pressure fluctuations, but this problem was unable to be examined here. The results suggested that an empirical formulation for each site is considered applicable rather than a theoretical approach, although the theories are being developed to practical application.  相似文献   

一些陆面要素非均匀分布对模式计算结果影响的理论分析   总被引：1，自引：1，他引：1       下载免费PDF全文

张正秋周秀骥  李维亮孙菽芬 《应用气象学报》2005,16(5):561-568

应用平均参数化方法,从理论上分别研究了地表温度、地面粗糙度、积雪深度和密度非均匀分布对相关物理量计算的影响。结果表明:考虑地表温度的非均匀分布影响后,模式网格上平均地面的长波辐射通量增加,地面饱和水汽压也增加;在相同的地表温度分布变差系数和常温情况下,与长波辐射通量相比,地面饱和水汽压的变化对地表温度非均匀分布较为敏感;地面粗糙度非均匀分布对地面中性曳力系数和BATS型地面积雪覆盖率有一定的影响;积雪深度和密度非均匀分布也对地面积雪覆盖率有一定的影响。  相似文献   

Wave trapping and flow around an irregular near circular island in a stratified sea     

Phil Dyke 《Ocean Dynamics》2005,55(3-4):238-247

Wave trapping and induced flow around an island is examined. The exactly circular island solutions are reprised and the solutions extended, and shown to apply to a stratified sea. The homogeneous solutions are then used to deduce the wave trapping and flow around a near circular island. It turns out that the cotidal pattern for a perfectly circular island is relatively immune to variations in geometry and radially dependent depth variations. This helps explain the similarity in the behaviour of the tides around various islands (the Pribilof Islands near Alaska, Oahu in Hawaii, Cook Island off north west Australia, Bermuda off the eastern coast of the USA, and Bear Island in the Norwegian Sea). The dominant steady drift and its rate of decay off-shore is also calculated.  相似文献   

物理场多重分形谱理论模型的数值模拟研究     

李锰  朱令人  唐丽华  龙海英 《内陆地震》2002,16(2):97-100

利用二维双标度三分非空集对物理场多重分形谱进行了理论模型的数值模拟研究。模拟结果表明：随着物理量空间分布不均匀性的增大，不同模型参数下的理论分形谱曲线变陡，Dq值域范围变宽。利用多重分形谱曲线的形态特征，可进一步了解是“稀疏区”还是“密集区”起主导作用，这对于从理论上把握物理和化学场分布特性具有重要意义。  相似文献   

同位素分馏理论计算新进展   总被引：1，自引：0，他引：1  

方涛 《地球科学进展》1997,12(3):253-258

稳定同位素分馏的理论计算，既是同位素理论研究的重要方面，也是矿物物理研究的重要课题，它涉及矿物的宏观性质和微观性质两个方面。自从Ｕｒｅｙ（１９４７）以来，人们提出了许多计算模式，但绝大多数模式都是以还原配分函数比作为出发点，以自由能变化为基础。从方法上表现出两种趋势，一是简化的趋势，以尽可能少的参数得到尽可能合理的结果；二是大型化和精确化趋势，以复杂的晶格动力学模式和计算机的大量应用为特征。随着这方面研究的深入，理论计算将成为人们了解矿物同位素分馏性质的重要途径。  相似文献   

用理论模式研究电离层F₁－ledge的变化   总被引：1，自引：0，他引：1       下载免费PDF全文

张顺荣 Radi.  SM 《地球物理学报》1996,39(5):601-607

利用一个时变电离层理论模式，研究武昌地区（３０．５°Ｎ，１１４．４°Ｅ）电离层Ｆ_１－ｌｅｄｓｅ现象．表明利用当前关于中性气体和太阳辐射的经验模式，观测到的Ｆ_１－ｌｅｄｇｅ出现与演化的基本规律将可基于现有电离层理论加以再现．指出较明显的Ｆ_１－ｌｅｄｇｅ结构同较低的中性原子－分子含量比有直接关系，并同原子－分子成份的过渡高度、背景温度及其垂直分布形态有一定联系．同Ｆ_１－ｌｅｄｇｅ形态相关联的Ｆ_１－Ｆ_２谷，其出现主要是由于亚稳态氧离子参与光化过程，以及电离气体参与具有一定垂直变化的输运过程．  相似文献   

过去全球变化研究中若干问题的反思     

吕厚远 《地球科学进展》1996,11(5):493-487

过去全球变化是ＩＧＢＰ计划的核心计划之一，科学家对过去会球变化的研究已经取得了许多意义的成果和积累了丰富的资料，对全球变化中的气候突变的必然性和偶然性，全球变化的确定性和不确定性及简单性和复杂性作一些反思，以求引起学术争鸣。  相似文献   

Theoretical and numerical analyses of pore-fluid flow focused heat transfer around geological faults and large cracks     

Chongbin Zhao  Bruce E. Hobbs  Alison Ord  Peter Hornby  Hans Mühlhaus  Shenglin Peng 《Computers and Geotechnics》2008,35(3):357-371

In this paper, theoretical and numerical methods are used to investigate pore-fluid flow focused temperature distribution patterns around geological faults and cracks of any length-scales in hydrothermal systems. If the far field inflow is uniform and the long axis of an elliptical fault of any length-scale is parallel to the far field inflow direction, a complete set of analytical solutions has been presented for the pore-fluid velocity, stream function and excess pore-fluid pressure around the elliptical fault embedded in fluid-saturated porous media. Because the analytical solutions are explicitly expressed in the conventional Cartesian coordinate system, not only can they be used to gain a theoretical insight into the pore-fluid flow patterns around geological faults and large cracks, but also they can be used as valuable benchmark solutions for validating any numerical methods. After a finite element computational model is validated by comparing the numerical solutions with the present analytical solutions, it is used to investigate pore-fluid flow focused heat transfer around geological faults in hydrothermal systems. Some interesting conclusions in relation to the effects of geological faults on pore-fluid flow focused heat transfer have been made through both the theoretical and the numerical analyses.  相似文献   

成矿作用动力学研究的新进展及发展趋势   总被引：1，自引：0，他引：1  

凌其聪 《矿产与地质》1998,12(6):361-366

成矿作用动力学是地球化学动力学的一个重要分支学科,近年给出了更完善的定义,初步建立了一套理论体系和研究方法。水岩相互作用及动力学模型、物质输运与化学反应、成矿元素的输运与沉淀、化学热力学与输运性质等方面的研究取得许多新的进展。最后指出了成矿作用动力学的某些发展趋势。  相似文献