Advances in Research on Soil Moisture by Microwave Remote Sensing in China

Soil moisture is an important factor in global hydrologic circulation and plays a significant role in the research of hydrology, climatology, and agriculture. Microwave remote sensing is less limited by climate and time, and can measure in large scale. With these characteristics, this technique becomes an effective tool to measure soil moisture. Since the 1980s, Chinese researchers have investigated the soil moisture using microwave instruments. The active re- mote sensors are characteristic of high spatial resolution, thus with launch of a series of satellites, active microwave remote sensing of soil moisture will be emphasized. The passive microwave remote sensing of soil moisture has a long research history, and its retrieval algorithms were developed well, so it is an important tool to retrieve large scale moisture information from satellite data in the future.     

Flow–stress coupled permeability tensor for fractured rock masses

In this paper a new analytical model is proposed to determine the permeability tensor for fractured rock masses based on the superposition principle of liquid dissipation energy. This model relies on the geometrical characteristics of rock fractures and the corresponding fracture network, and demonstrates the coupling effect between fluid flow and stress/deformation. This model empirically considers the effect of pre‐peak shear dilation and shear contraction on the hydraulic behavior of rock fractures and can be used to determine the applicability of the continuum approach to hydro‐mechanical coupling analysis. Results of numerical analysis presented in this paper show that the new model can effectively describe the permeability of fractured rock masses, and can be applied to the coupling analysis of seepage and stress fields. Copyright © 2008 John Wiley & Sons, Ltd.     

SMALL项目数字化地磁资料可靠性分析

在对中美合作 SMALL (中国低纬地磁台阵 )项目安装在北京地磁台 (白家疃 )和云南通海地磁台的磁通门磁力仪记录资料与磁变仪模拟记录资料进行了详细的对比分析后 ,得出的结果表明 ,两者的日变形态、日变幅有较好的一致性 ,所选特定事件的变化幅度非常一致 ,说明磁通门磁力仪记录到的变化磁场的资料是真实可靠的。尽管目前磁通门磁力仪的基线值存在温度影响和离散度较大的问题 ,但随温度变化有明显的规律性 ,若能采取改进观测条件和观测方法以及缩短观测时间等措施 ,并对基线值进温度校正 ,磁通门磁力仪完全可以提供长期连续可靠的资料。而其为地震预报 ,空间环境预报 ,为日地物理 ,空间物理和地磁学的研究提供的高精度、高分辨率、连续可靠的数字化变化磁场资料是磁变仪模拟记录无法比拟的。     

用VB语言实现地震观测资料格式转换

VB编程语言提供了图形环境 ,能可视化的设计窗体和控件。本文介绍了应用该设计语言的特性如何实现地震资料的格式转换     

基于VisualC 平台的多边形裁剪算法实现

详细叙述了利用ＶｉｓｕａｌＣ＋＋提供的函数进行多边形裁剪的算法实惠过程,并给出了多边形带“岛”情况的具体处理方法。     

主成分分析在双壳类软体动物研究中的应用

用主成分分析方法通过计算机把雌性青蛤的软体部干重和3个生化指标综合为肥满指标和能源物质指标,从而允许用二维图象来显示。14个样品明显地分为碳水化合物为主要贮存能源物质和脂类、蛋白质为主要贮存能源物质两类。两个新指标的累积贡献率达94％。     

金属矿床氧化带中铁矿物的演化及其与金次生富集的关系

作为地壳中常见的主要变价元素—铁 ,它与金在内生成矿及表生再富集过程中的关系十分密切。铁在矿床中的分布及铁的硫化物矿物在氧化过程中演化的阶段性与环境的Eh值,pH值有着密切关系;进而影响和控制了金在表生演化过程中的地球化学行为。     

使用量化器件获得高精度测量方法的几点讨论

本文从列阵器件测量精度的估计公式出发，推导了用低精度Ａ／Ｄ变换器件获得高精度测量结果的一般性证明，还讨论了这种方法的若干可能应用。     

A Simple Shear Model for the Asymmetry in the Paleoproterozoic Fold Belt in Liaodong Peninsula

IntroductionThe Liaodong Paleoproterozioc fold belt is locat-ed at eastern China -- Korea craton, from Liaodongpeninsula through southern Jilin to north Kore$tothe east, to west Jiaodong peninsu1a to the west. Al-though many discussions, in the literature…