水体镜面反射的多角度偏振特性研究及应用

基于水体样本的多角度偏振反射光谱，对水体镜面反射的偏振特性和机理进行了系统地研究。实验中，通过改变光线入射角、探测角、探测方位角、偏振角等影响因子，得出了水体样本的多角度偏振反射光谱的普适规律。在多角度遥感与偏振光技术的物理基础上，提出了基于多角度偏振反射的水体镜面反射消除方法和进行水体偏振遥感的适宜时间设计方法，为多角度偏振技术在水体遥感中的应用提供了技术参考。     

月球探测及月球重力场的确定

针对近年月球探测渐成热点和我国即将发射“嫦娥卫星”的状况，本文首先归纳了月球各项几何与物理特性以及月球探测的经济、科学和战略意义.然后，讨论了月球重力场在探月中的作用，并对国外月球重力场研究的发展历程、主要方法及面临的困难进行了综述.最后，结合我国“嫦娥工程”，对我国月球重力场探测的可行性，从航天运载能力、轨道跟踪手段、重力场恢复技术以及方法创新等方面进行了分析，以期为我国自主确定月球重力场模型提供参考依据.     

月球探测中若干问题的研究及进展

本文主要介绍了在第二次探月高潮中对于月球重力场、月球天平动、月球耗散效应等月球物理特性的研究成果,以及建立月球参考框架以及布设月面控制网等月球大地测量方面的方法和进展,并探讨了月球探测过程中应用到的相关技术,最后,对月球探测的进一步发展做出展望.     

月震和遥感探测技术的发展对月球内部结构认识的深化

基于月球内部结构的主要探测手段,即早期绕月卫星重力观测、月面月震观测和月球高分辨率遥感观测与月震数据的综合应用,可将月球内部结构的认识过程分为三个阶段,文章分别对这三个阶段的观测技术、数据情况、数据处理及代表性研究成果进行了详细的介绍及评述,阐明了探测技术的发展对月球内部结构认识的深化过程:通过早期绕月卫星摄动观测获得的低阶月球重力场开启了对月球内部结构的初步认知,发现月球表面存在高密度异常体(即质量瘤);早期的月震观测是月球内部结构认识的重要手段,获得了月球圈层结构的轮廓;月球高分辨率遥感数据,作为外部数据为月球内部结构的研究提供了更多的约束,同时,与月震数据的综合应用,深化了对月球内部结构的认识.最后对月球内部结构研究中尚存在的问题及探测技术的发展前景进行了分析和展望.     

“嫦娥一号”微波探测仪探测月壤厚度机理和地面验证实验

“嫦娥一号”微波探测仪（CELMS）是国际上首次在月球轨道直接测量月球亮温的被动微波遥感器,其科学目标是反演月壤厚度的信息并对月球的3He资源量和分布进行评估.介绍了月壤厚度探测机理,建立了亮度温度随月壤厚度变化的理论模型,利用地面验证实验对探测机理和辐射传输模型进行了初步验证.     

曲靖非相干散射雷达观测研究进展与展望

本文介绍了我国曲靖非相干散射雷达的主要技术方案，结合实测数据分析表明该雷达具备了电离层电子密度与等离子体温度观测、空间碎片凝视探测与月球二维成像探测等能力，可用于研究电离层F层气候学特征、电子密度暴时变化与异常增强等天气事件、E-F谷区结构与变化、约3 cm以上尺寸空间碎片的分布特征与模型、月球不同区域的散射回波特性等.下一步将重点开展低电离层与北驼峰结构及演化过程、电离层暴时与扰动特性观测.     

雷达探测仪对月球次表层结构的探测模拟方法

在月球探测中,星载高频雷达探测仪(HF Radar Sounder)通过月球表面天底点和次表面天底点的回波时延差与强度探测月球分层结构.电磁波在月球分层结构内散射与传播的建模与模拟,对于从雷达探测仪回波中提取微弱的次表面天底点回波,获取次表层结构信息等有重要的意义.本文基于粗糙面散射的Kirchhoff近似与几何光学射线追踪,提出月球分层结构雷达探测回波的模拟方法.根据月球表面地形特征,由规则三角形网格对月表面地形进行数值剖分,数值计算月球表面与次表层面的雷达回波,模拟绕月飞行的星载雷达探测仪对月球表面与次表层结构的探测图像,分析月球表面特征性物理参数对回波的影响.本文所述方法也可以应用到火星等其他外星球次表层结构的探测中.     

月球重力场对月球内部结构研究的作用

月球是人类深空探测的首要目标,而月球的内部结构则是我们了解月球与地月系形成与演化的重要窗口.相比于其他物理场,月球重力场模型具有全球均匀覆盖、精度和分辨率持续提高的特点,在月球内部结构研究中扮演着重要作用.本文对月球重力场在月球内部结构研究中发挥的作用进行了论述,包括月壳、月幔以及月核,其中重点介绍了高阶次重力场模型对...     

绕月探测工程的初步科学成果

嫦娥一号是我国发射的第一个月球轨道探测器, 是中国月球探测工程“绕”、“落”、“回”发展战略的第一步. 嫦娥一号于2007年10月24日在西昌卫星发射中心成功发射, 2009年3月1日受控落月于52.36°E, 1.50°S的丰富海区域, 在轨运行495天, 比预期一年的工作寿命延长4个多月, 一共获得了1.37 TB的原始科学探测数据, 在此基础上目前已生产出约4 TB科学应用数据产品. 通过对这些科学探测数据的初步分析和应用研究, 已经获得了包括“中国首次月球探测工程全月球影像图”在内的一系列科学成果, 圆满实现了预期的各项科学目标, 为推动我国月球科学和天体化学的研究和后续月球探测工程的开展奠定了重要基础.     

偏振分析在地震信号检测中的应用

给出了一种3分量地震数据偏振分析的技术,并将其应用到人工地震勘探信号的提取中。该技术基于时域算法,通过对协方差矩阵的本征分析,在滑动时间窗内计算偏振特性,由偏振椭圆导出表征质点运动的各种属性,并利用质点运动的特征构建偏振滤波器。本文对3分量合成地震记录和野外探测实验的实际3分量记录进行偏振分析研究,并在此基础上进行偏振滤波,有效地提高了信噪比。     

Research and application of multi-angle polarization characteristics of water body mirror reflection

On the basis of the multi-angle polarized reflection spectrum of the water samples,the water body mirror reflection polarization characteristics and mechanism are described systematically. By altering such influential factors as the angle of incidence,detecting angle,detecting azimuth angle and polari-zation angle,ubiquitous laws for the multi-angle polarized reflection spectrum of the water samples are obtained. Combining multi-angle remote sensing with polarized light,the multi-angle polarized reflec-tion method about eliminating the water body mirror reflection and the suitable time of the polarized remote sensing of the water body are proposed. This study provides technical references for the ap-plication of multi-angle polarization technology on water body remote sensing.     

机载探地雷达数值模拟及逆时偏移成像

机载探地雷达可以用于人类无法到达的危险地区、植被严重覆盖的地下目标体探测,然而由于机载探地雷达的特殊性,影响机载探地雷达探测效果的因素包括天线的极化方向、天线的飞行高度以及地表粗糙度等.为了研究这些影响因素与探测效果之间的关系,用三维时间域有限差分模拟电磁波的传播过程,以沙漠地区地下空洞掩体的机载探地雷达探测为实例,分别模拟了不同天线极化方向、天线高度及地表粗糙度情况下的机载探地雷达剖面,分析了各因素对机载探地雷达探测地下空洞目标体的影响.天线极化方向与目标体走向垂直更有利于地下目标体探测;天线距离地表越近,可以获得更高分辨率的雷达剖面;沙漠地表起伏越大,雷达剖面中的散射杂波能量越强,浅部地下目标体信号容易被掩盖.为了消除起伏地形造成的散射杂波,提出用逆时偏移成像技术对共炮集机载探地雷达数据进行偏移成像,成像结果优于基尔霍夫偏移成像结果.     

A high accurate automated first-break picking method for seismic records from high-density acquisition in areas with a complex surface

As the application of high-density high-efficiency acquisition technology becomes more and more wide, the areas with complex surface conditions gradually become target exploration areas, and the first-break picking work of massive low signal-to-noise ratio data is a big challenge. The traditional method spends a lot of manpower and time to interactively pick first breaks, a large amount of interactive work affects the accuracy and efficiency of picking. In order to overcome the shortcoming that traditional methods have weak anti-noise to low signal-to-noise ratio primary wave, this paper proposes a high accurate automated first-break picking method for low signal-to-noise ratio primary wave from high-density acquisition in areas with a complex surface. Firstly, this method determines first-break time window using multi-azimuth spatial interpolation technology; then it uses the improved clustering algorithm to initially pick first breaks and then perform multi-angle comprehensive quality evaluation to first breaks according to the following sequence: ‘single trace → spread → single shot → multiple shots’ to identify the abnormal first breaks; finally it determines the optimal path through the constructed evaluation function and using the ant colony algorithm to correct abnormal first breaks. Multi-azimuth time window spatial interpolation technology provides the base for accurately picking first-break time; the clustering algorithm can effectively improve the picking accuracy rate of low signal-to-noise ratio primary waves; the multi-angle comprehensive quality evaluation can accurately and effectively eliminate abnormal first breaks; the ant colony algorithm can effectively improve the correction quality of low signal-to-noise ratio abnormal first breaks. By example analysis and comparing with the commonly used Akaike Information Criterion method, the automated first-break picking theory and technology studied in this paper has high picking accuracy and the ability to stably process low signal-to-noise ratio seismic data, has a significant effect on seismic records from high-density acquisition in areas with a complex surface and can meet the requirements of accuracy and efficiency for massive data near-surface modelling and statics calculation.     

应用单台垂向记录进行区域地震事件实时检测和直达犘波初动自动识别

提出一种基于直达P波信号和其它背景噪声在能量、非高斯性、非线性和偏振特性的不同而进行区域地震事件实时检测的新方法信噪综合差异特征量方法（简写为EFGLP方法）,同时对比分析了应用信号的不同统计特性来精细识别震相初至的３种有效方法,其中的TOC AIC方法是新提出的．应用山东数字地震波资料处理的结果表明:①与常规的STA/LTA地震事件触发算法相比,EFGLP方法能够有效降低地震事件的错误报警率和漏报率;②与人机交互震相识别结果相比,当信噪比比较低、震相初至比较模糊时,3种震相精细识别方法中的TOC-AIC方法识别精度最高;当信噪比比较高、震相初至比较清晰时,基于VAR-AIC 和TOC-AIC方法所测量得到的震相初至识别基本一致．      

Seismomagnetic signals from the strong Sumatra earthquake

Electromagnetic oscillations generated by surface Love waves in the Earth’s crust were detected by the spectral polarization method at the Mondy and Sodankylä observatories, located at distances of 5390 and 8798 km from the epicenter of the strong Sumatra earthquake of December 26, 2004. Detailed analysis of this event is instructive because it indicates that the difficulty in detecting the coseismic magnetic oscillations predicted by theory is only due to the presence of strong noise. Observations of this type are shown to be significant for experimental studies of mechanoelectromagnetic conversions in the crust.     

Precise arrival time detection of polarized seismic waves using the spectral matrix

I present a statistical method for detecting the arrival times of polarized seismic waves on three-component seismic observations in the time and frequency domains. In this method, the polarization, which is a representation of the 3D particle motion of seismic waves, is evaluated on the basis of a spectral matrix in the time and frequency domains and the statistical parameters are defined by using the eigenvalues of the spectral matrix for detecting the arrival times of linearly and elliptically polarized waves, where the idea of a statistical test of hypothesis is introduced. An evaluation of a synthetic signal revealed that the method can detect the arrival times of linearly and elliptically polarized waves within 10 sampling points at signal-to-noise ratios of −7 dB. Application of the method to an earthquake suggested that it can be used to detect the arrival times of both linearly and elliptically polarized waves, which are difficult to identify manually.     

Genetic inverse algorithm for retrieval of component temperature of mixed pixel by multi-angle thermal infrared remote sensing data

After carefully studying the results of retrieval of land surface temperature(LST) by multi-channel thermal infrared remote sensing data, the authors of this paper point out that its accuracy and significance for applications are seriously damaged by the high correlation coefficient among multi-channel information and its disablement of direct retrieval of component temperature. Based on the model of directional radiation of non-isothermal mixed pixel, the authors point out that multi-angle thermal infrared remote sensing can offer the possibility to directly retrieve component temperature, but it is also a multi-parameter synchronous inverse problem. The results of digital simulation and field experiments show that the genetic inverse algorithm (GIA) is an effective method to fulfill multi-parameter synchronous retrieval. So it is possible to realize retrieval of component temperature with error less than 1K by multi-angle thermal infrared remote sensing data and GIA.     

基于Zoeppritz偏导方程精确解的地层密度多角度反演

基于Zoeppritz方程对介质密度偏导数所建立的偏导方程的精确解,构造了多角度反演地层介质密度的反演方程,在偏导数求解过程中考虑了介质密度对波速度的影响因素,并由此实现了利用反射系数梯度精确解计算地层密度的多角度联合反演.通过数值算例考察了计算方法,结果显示:反演方法对层状地层模型不论反射波是否存在相干现象均获得了较好的反演结果,反演迭代10次后计算结果的最大相对误差能够收敛到1%之内;随着反演角度的增加地层介质密度反演的精度逐步提高,反演具有自动校正能力,有快的计算速度.本方法克服了传统AVO(Amplitude Versus Offset)基于Zoeppritz方程近似所遇到的困难,不受反演角度大小及反射界面对波反射强弱的限制,为地层介质密度的多角度包括大角度反演提供了一种新的快速有效的计算方法.     

深部地应力探测技术理论探讨

地应力测量的研究已有几十年的历史,但是对于地下深部地应力非钻孔式测量探测技术的发展,则一直进展很慢。本文依据天然电磁波场源,利用光弹实验模型原理,研制了ＤＹＬ型地应力探测仪,并在淮南地区地庆力状态普查过程中,取得了明显的应用效果。     

Polynomial analysis of canopy spectra and biochemical component content inversion

Vegetation is an important component of the eco-system, and to estimate accurately the biochemical component content is very helpful to understanding the ecosystem functions at different scales. While the method to retrieve biochemical component content using leaf scale spectral measurements is applicable, to retrieve biochemical component content from can-opy spectra is still a challenging problem. Because canopy spectra are the combined results of leaf bio-chemical component content, soil ba…