Non-axisymmetric guided waves in a composite cylinder with transversely isotropic core     

N. Rattanawangcharoen  Subhendu K. Datta  Arvind H. Shah 《Geophysical Journal International》1994,118(2):317-324

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TM 假彩色合成卫片在土地详查中的应用     

史生芳  蒋明来 《青海国土经略》1993,(1)

文内涉及的 TM 假彩色三波段合成卫片的波长分别为,TM2 0.53—0.61μm,TM3 0.63—0.69μm,TM4 0.78—0.90μm。根据波谱规律卫片能直观地反映区内各地理要素的空间结构及区域分布规律。作者在玉树地区的土地调查中,利用各地类图斑的影像色调特征,建立了解译标志,结合地形图能较好地确定各地类的准确界线,显示清晰的图面结构。  相似文献   

The stress field in Australia from composite fault plane solutions of the strongest earthquakes in the continent     

Edelvays Spassov 《Journal of Seismology》1998,2(2):173-178

The purpose of this study is to make an estimate of the stress field in the Australian continent from composite fault plane solutions of the strongest events in the area. 21 seismic events with magnitude greater than 5.0 have been chosen from a database of 400 Australian earthquakes since 1902 for performing composite fault plane solutions. The choice is based on the availability of data for first P-wave arrivals. Using data from ISC bulletins we have calculated composite fault plane solutions for six major earthquake zones in the country. An individual fault plane solution for at least one event in each zone has been computed, too. The space distribution of the focal mechanisms confirms a dominant east-west compression stress in the continent, with different tilt in different areas. The main compression axes in the Tennant Creek area (Northern Australia) are with clear north-south direction. The general direction of the plate motion is north-northeast.  相似文献   

天气动力学组合因子在MOS降水预报中的应用   总被引：3，自引：0，他引：3  

孙永刚  李彰俊  孟雪峰  刘增良  孔令红 《气象》1998,24(2):27-30

利用我国的数值产品ＨＬＡＦＳ格点场资料,结合内蒙古地区降水系统的天气动力学演变特征,构造出能反映降水系统的天气动力学发展机制的结构特征因子,采用ＭＯＳ方法建立预报方程。用较短的样本资料建立ＭＯＳ预报方程,提高了ＭＯＳ预报方程的预报能力和适应性。试验结果表明,该ＭＯＳ预报方程计算稳定并具有很好的预报能力和效果,易于业务化。  相似文献   

定海—朱家尖海峡大桥工程选址评析     

赵竹占 《浙江国土资源》1998,(1)

本文介绍在定海—朱家尖海峡大桥选址阶段,采用工程地球物理的浅地层剖面法和多次覆盖水上浅地震勘查,取得良好的块质效果,为朱家尖海峡大桥选址提供了科学的地质依据。  相似文献   

复合地基沉降的复合本构有限元分析   总被引：27，自引：7，他引：20  

杨涛  殷宗泽 《岩土力学》1998,19(2):19-25

提出了平面应变条件下复合地基沉降计算的复合本构有限元法。根据桩土界面处力的平衡条件和竖向变形协调条件,由桩、土材料各自的本构方程形成复合地基的本构方程,桩和桩周土可以采用任意非线性本构模型。工程实例分析表明,所建议的方法是有效的。  相似文献   

桩体复合地基柔性垫层的效用研究   总被引：25，自引：4，他引：21  

毛前  龚晓南 《岩土力学》1998,19(2):67-73

从阐述复合地基与桩基之间的区别入手,通过对桩体刺入垫层的研究,寻找在桩头呈理想球形孔条件下,垫层、桩体、桩间土三者模量与刺入量之间的关系,进而讨论了在刺入模式下的加固区复合模量计算问题。还讨论了复合地基桩上材料最优发挥状态问题,力图寻找最佳的桩土荷载分担比。  相似文献   

桩式复合地基承载特性的研究   总被引：8，自引：1，他引：7  

娄国充 《岩土力学》1998,19(1):70-74

以桩式复合地基为对象,将复合地基视为由垫层、桩和桩间土所组成的一个工作体系,考虑其各部分的工作特性及其相互影响,分析研究了复合地基的受荷机理,影响桩土应力比和复合地基承载力的诸多因素等。  相似文献   

复合型海洋防污涂料的研究     

吴伟新  李兰生  魏棣 《海洋湖沼通报》2009,(1)

选择氯醚树脂作为涂料的成膜物,对天然植物辣椒中提取的辣椒碱和防霉杀菌荆构成复合防污剂的特性进行了分析,经多次加速试验及海港浮筏挂片检测,从中优选出综合性能较好的涂料配方,为实船试验打下良好的基础.  相似文献   

Wellbore flow‐rate solution for a constant‐head test in two‐zone finite confined aquifers     

Chi‐Shan Tsai  Hund‐Der Yeh 《水文研究》2012,26(21):3216-3224

The solution describing the wellbore flow rate in a constant‐head test integrated with an optimization approach is commonly used to analyze observed wellbore flow‐rate data for estimating the hydrogeological parameters of low‐permeability aquifers. To our knowledge, the wellbore flow‐rate solution for the constant‐head test in a two‐zone finite‐extent confined aquifer has never been reported so far in the literature. This article is first to develop a mathematical model for describing the head distribution in the two‐zone aquifer. The Laplace domain solutions for the head distributions and wellbore flow rate in a two‐zone finite confined aquifer are derived using the Laplace transform, and their corresponding time domain solutions are then obtained using the Bromwich integral method and residue theorem. These new solutions are expressed in terms of an infinite series with Bessel functions and not straightforward to calculate numerically. A large‐time solution for the wellbore flow rate is therefore developed by employing the relationship of small Laplace variable versus large time variable and L'Hospital's rule. The result shows that the large‐time solution is identical to the steady‐state solution obtained after applying the Tauberian theorem into the Laplace domain solution. This large‐time solution can reduce to the Thiem equation in the case of no skin. Finally, the newly developed solution is used to investigate the effects of outer boundary distance and conductivity ratio on the wellbore flow rate. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献