遥感技术在探查杨庄矿朱庄矿奥灰水中的应用

应用遥感技术查明了杨庄矿和朱庄矿奥灰水的径流条件,所圈定的补给地带,经钻探得到了验证。      

鹅婆复式深成岩体成岩时代初探

本文以１：５万青塘幅、黄石幅区调资料为依据,对鹅婆复式深成岩体的成岩时代从地质特征、岩石学特征、岩石化学特征、同位素年龄等多方面进行了分析,认为鹅婆复式深成岩体形成于加里东晚期。     

江西中部青白口纪晚期潭头上升雏议

青白口纪神山组与库里组之间有沉积间断,存在岩相、沉积环境突变界面,两者为平行不整合接触关系,对这一地壳上升运动,命名为潭头上升。     

Chandler摆动的非线性分岔耗散

在已有的Ｃｈａｎｄｌｅｒ摆动非线性共振激发模型的基础上,引入微小的非线性项,得到不可忽略的非线性分岔解。实际上,Ｃｈａｎｄｌｅｒ摆动方程是可用线性阻尼非线性平面单摆来逼近的,由Ｄｕｆｆｉｎｇ方程可以求得方程的解。     

中世纪暖期温度变化的模拟

本文利用全球海气耦合气候模式ECHO-G进行的1000个模式年的长时间积分气候模拟试验结果,分析全球和中国地区中世纪暖期的存在性与时间演变、全球性与区域差异、以及变温强度和影响因子等问题．结果表明:中世纪暖期是一个全球性现象,但各地在中世纪暖期温度变幅和位相变化存在差异．中世纪暖期不是一个持续稳定的暖期,而是存在峰谷起伏变化,其中冷谷的持续时间为40-80年．全球平均的中世纪暖期出现在1000—1280年间．其间南半球的温度变幅最大,北半球次之,全球平均最小．中世纪暖期的鼎盛期全球绝大部分地区增温明显,只有大西洋西北地区有一 0．5-1,0℃的降温区,以及南太平洋有-0．5-2．0℃的降温区．北半球最大增温出现在格陵兰地区及西北太平洋地区, 南半球出现在70°-80°S,5°-60°W的海域,最大增温达2．5-3．0℃．整个欧亚大陆和北美大陆都是增温区,增温幅度为 0．5-1．5℃．热带和亚热带也是增温区,但增温幅度仅为0．5℃左右．也就是说,中世纪暖期时,增温幅度在低纬地区最小,中纬度地区次之,高纬度地区最大．中国的中世纪暖期出现在公元1000—1260年间,其间中国西部的年平均温度距平变幅最大,东部最小,全国平均介于二者之间．中世纪暖期鼎盛期整个中国区域温度距平都是正值,中国东部的增温呈西 -东向和西北-东南向的带状分布,且由南向北增温幅度加大,由0．4℃逐步增加到0．8℃．中国西部的增温呈高压状分布,且随着海拔高度的增加,增温幅度加大,最大增温达2．0℃-2．2℃．由于模拟试验是在改变太阳辐射、火山活动、CO2 与CH4浓度等因子的情况下进行的,说明太阳辐射、火山活动、CO2与CH4浓度都是形成中世纪暖期的主控因子．至于各因子各自对中世纪暖期形成的贡献,还有待进行单因子和多因子强迫试验进一步探讨．     

Explanation of locking of four‐node plane element by considering it as elastic Dirichlet‐type boundary value problem

The aim of this study is to arrive at a better understanding of the phenomenon of locking of low‐order compatible displacement type of finite elements in particular for the hour‐glass mode of the plane four‐node element and dilative materials. To this end the properties of finite elements are investigated in an analytical way, where a finite element is considered as a plane boundary value problem with prescribed boundary displacement (Dirichlet problem). In this paper for the sake of simplicity the simplest possible linear comparison solid, namely isotropic linear elasticity, is applied, although recognizing fully that for a dilative material elasto‐plasticity would be more realistic. From the study described in this paper it is concluded that locking of the four‐node element is not due to any particular numerical formulation of this compatible finite element since, even the analytical solution suffers from this problem. The locking of this element is not related to incompressibility of the material either as the analytical solution shows locking to occur at a parameter set which differs significantly from the one in case of incompressibility. It is shown that locking is a consequence of the combination of the dilative material behaviour and the compatible displacement type of boundary conditions, which leads to infinite isotropic stresses in the element. These infinite isotropic stresses occur at the limit of uniqueness of the solution, which for this element is shown to occur outside the parameter range of the sufficiency of uniqueness. Copyright © 2000 John Wiley & Sons, Ltd.     

浮游生态系统非线性动力学研究

建立了新的藻类-浮游动物生态非线性动力学模型,该模型考虑了藻类与浮游动物之间的增长关系。研究了模型平衡点的稳定性,以及Hop f分岔现象。通过对选取的分岔参数进行分析,揭示了该系统的动力学特性。     

非对称双环神经网络系统的稳定性和Hopf分岔

环型结构在神经网络中普遍存在,目前对环型神经动力学分岔研究大多数局限于单环情形.值得注意的是,神经网络由成千上万个神经元耦合而成,这些复杂的神经元网络结构不可能只由一个环形结构来准确表述,因此研究具多环拓扑的神经网络模型更具实际意义.本文提出了一种非对称双环神经元网络模型,选择单环的时滞和为分岔参数,分析了双环模型的稳定性和Hopf分岔.最后给出数值仿真对结论进行了验证.     

A polarized microwave radiative transfer model for passive remote sensing

The objective of the present work is to develop a general purpose, polarized, microwave radiative transfer forward model, including calculation of interaction parameters for fast, simultaneous and accurate generation of radiances, for use in a wide variety of atmospheric retrieval applications. This complete polarized model includes the generation of atmospheric profiles, calculation of the interaction parameters and the solution of the vector radiative transfer equations. In the present work, the doubling and adding method is used to calculate radiances. Mie theory is used for spherical particles to evaluate the polarized scattering matrix. Two types of sea surface models applicable for specular and diffuse surfaces respectively are implemented. The model has been validated against standard benchmark cases and experimental data available in literature. While the model is itself generic, parametric studies are performed to study the influence of the vertical structure of the atmosphere, for two polarizations and a set of frequencies to be used on the microwave imager aboard the proposed Indo-French climate research satellite MEGHA-TROPIQUES.     

云南夏季风振荡与降水的关系

用功率谱方法分析了云南几个代表站１９８５－１９８７年共３年５－１０月低层夏季风活动和降水的振荡周期。然后用交叉谱分析了这两者在显著周期下的相关关系和位相关系。发现云南夏季风活动与雨季降水都有相近的振荡周期，且在显著的振荡周期中两者关系较好。当夏季风偏强时，降水就会偏多。反之，当冷空气偏少偏弱，而夏季风又偏弱时，这一年会发生严重干旱。