测站位移固体潮效应的潮波公式

固体潮对测站位移的影响是空间大地测量和天文地球动力学研究的重要组成部分。对目前常用的3种引潮力位展开形式进行了总结，并列出了它们各自的实用公式。不同于IERSl996和IERS2000推荐的固体潮对测站位移影响的理论模型，独立于天体历书而基于精密引潮力位展开，直接给出了在亚毫米精度下的潮波公式，利用新的精密引潮位展开在亚毫米精度上重新计算了永久性潮汐的影响。可为高精度的空间大地测量和天文地球动力学的研究提供理论依据和参考。     

Turbulence Structure in the Wake Region of a Meteorological Tower

A meteorological tower significantly modifies the air flow, the mean windspeed and wind direction as well as the turbulencestructure of the air. Suchchanges can be noticed in particular in the wake region of the tower.Measurementson the 200 m tower ofForschungszentrum Karlsruhewere carried outusing Solent sonic anemometers in the lee of the towerand cup anemometers on both sides.In the wake region, spectral energydensity is increased in the high-frequency range. Superposition of this disturbance spectrum on the undisturbedspectrum yields a `knee' in the resulting spectrum. In the case of low turbulence intensity with stable stratification,a plateau with a constant energy content is observed in front of the knee.This effect is caused by the new production of turbulence energy from the mean flow as well as by an energy transfer fromlarger to smaller vortices. Power spectra in strongly stable conditionsshow a more rapid decrease of intensity in the region where the inertialsubrange is expected.The relevant scales of wake turbulence are derived from the maximum of the disturbance spectrum.Locations of the high-frequency peak do not depend on atmospheric stability,but are controlled mainly by mean wind speed.Apart from the reduction of the mean wind speed, the spectra and cospectra exhibit a strong anisotropy for such cases.The results demonstrate the significant influence of a tower on turbulence spectra in the wake region.     

An Incremental Response Spectrum Analysis Procedure Based on Inelastic Spectral Displacements for Multi-Mode Seismic Performance Evaluation

The so-called Nonlinear Static Procedure (NSP) based on pushover analysis has been developed in the last decade as a practical engineering tool to estimate the inelastic response quantities in the framework of performance-based seismic evaluation of structures. However NSP suffers from a major drawback in that it is restricted with a single-mode response and therefore the procedure can be reliably applied only to the two-dimensional response of low-rise, regular buildings. Recognizing the continuously intensifying use of the pushover-based NSP in the engineering practice, the present paper attempts to develop a new pushover analysis procedure to cater for the multi-mode response in a practical and theoretically consistent manner. The proposed Incremental Response Spectrum Analysis (IRSA) procedure is based on the approximate development of the so-called modal capacity diagrams, which are defined as the backbone curves of the modal hysteresis loops. Modal capacity diagrams are used for the estimation of instantaneous modal inelastic spectral displacements in a piecewise linear process called pushover-history analysis. It is illustrated through an example analysis that the proposed IRSA procedure can estimate with a reasonable accuracy the peak inelastic response quantities of interest, such as story drift ratios and plastic hinge rotations as well as the story shears and overturning moments. A practical version of the procedure is also developed which is based on the code-specified smooth response spectrum and the well-known equal displacement rule. This revised version was published online in July 2006 with corrections to the Cover Date.     

地球主磁场的能量密度谱及其长期变化

根据BJ地磁场模型和第8代国际地磁参考场(IGRF)模型，计算并分折了1690～2000年期间地球表面主磁场和分量的能量密度谱及其长期变化。结果表明1690～2000年期间主磁场的能量密度谱一直在减小，其主要原因是由于偶板子磁场的衰减产生的，而非偶板子磁场的能量密度谱在1690～1780年期间减小，1780～1890年增大，1890年以后快速增大。在地磁场总能谱的变化中，Z分量的贡献起主要作用。能量密度随谐波阶数的变化在半对数坐标中近似线性，非偶板子场的等效磁源深度位于核幔边界附近，n＝1，2谐波项的等效磁源位于地球内核边缘，其位置随时间变化。1780和1890年前后是地磁场变化的转折时期。能量密度谱的长期变化存在大约60a的周期规律。     

声频谱测井方法研究进展

主要介绍声频谱测井方法的理论基础和解释应用．声频谱测井作为一种新的声波测井方法，它是利用多个频率实现对井壁附近不同径向深度处地层的探测．首先介绍了声频谱测井方法的理论基础，在此基础上在声频谱声系中设计了10K、20K、40K三种不同主频的声波探头组合，结合声频谱参数与岩石储集参数的关系，设计了声频谱测井的基本解释方案，探讨了声频谱测井解释方法在确定孔隙度、渗透率、识别油气、裂缝，以及岩石力学参数计算及过套管测井等方面的应用．     

周至深井水震波数字化记录与地震波记录的对比研究

介绍了周至深井井孔概况和水位观测的仪器设备配置，通过对2000年10月6日日本本州7．3级地震的水震波数字化记录的频谱分析，与陕西数字地震台网同一地震事件进行对比研究，结果表明，周至深井可以记录到周期大于2s的水震波，对地动位移的放大倍率约为200倍，带宽大于DK-1地震仪和FBS-3地震计，相当于一台深井宽带地震仪。     

轻轨铁路站桥结构体系抗震分析与隔震研究

本文结合地处高烈度地震区的天津轻轨工程，对轻轨铁路站桥结构体系进行抗震分析，并探索减轻其地震灾害、提高其抗震能力的隔震措施。研究结果表明，按照现行有关抗震设计规范规定的反应谱值设计的站桥结构体系的抗震安全性存在不足，设计必须按工程建设场地地震危险性评价给定的反应谱值对站桥结构体系进行时程分析，才能保证轻轨铁路的抗震安全性。通过在车站建筑与高架桥梁之间的连接部位安装新近研制的SMA复合橡胶支座隔震装置，可以有效地提高轻轨铁路站桥结构体系的抗震能力。     

成像光谱数据建模与分类识别技术研究——以云南腾冲矿区为试验区

在系统分析成像光谱数据特征及岩石矿物具有诊断意义的吸收光谱特征形成机理的基础上，采用基于相关系数测度的光谱匹配技术、基于高斯改进型模型的光谱建模技术及人工神经网络分类算法，实现了岩石矿物光谱特征波形对比分析及诊断光谱信息提取与建模，提高了光谱分类识别算法的计算速度和分类精度。采用上述技术对云南腾冲铀矿区进行实验研究，取得良好效果。     

多道伽马能谱仪中的特征峰稳谱技术

介绍一种用于微机多道伽马能谱仪的稳谱装置及稳谱方法,该装置采用新型非易失性数字电位器、89C52控制器等大规模集成电路,具有集成度高、功耗低、可靠性高等优点.文中详细介绍了有关软硬件、稳谱方法及实际应用效果.试验结果表明,对102道微机伽马能谱仪在-5～5 ℃的工作环境下,其特征峰漂移≤±1道.     

角度谱在快慢横波分离中的应用

横波在穿越裂隙介质时会分裂成平行裂隙的快横波和垂直裂隙的慢横波，其偏振角随着波传播的时间和空间而变化。利用角度谱可以有效地求取偏振角，从而分离快慢横波。这里介绍了角度谱的概念及其应用。