城镇建筑震害SAR遥感探测与评估研究综述     

龚丽霞  张景发  曾琪明  吴樊 《地震工程与工程振动》2013,33(4)

合成孔径雷达(SAR)遥感是城镇建筑震害监测的重要手段之一.随着SAR传感器技术的最新发展,利用高分辨率、多极化SAR图像对城镇建筑地震灾害损毁进行探测和评估成为当前的研究趋势和热点.文中首先分析了建筑物及其震害损毁SAR成像特点,并系统综述了近15年来国内外基于SAR图像进行城镇建筑震害损毁探测与评估技术方法的研究和应用现状,评述了各类方法的优缺点,最后针对当前SAR传感器高分辨率、全极化的发展趋势,对有待于进一步研究的问题和技术发展趋势进行了展望.  相似文献   

Investigating hydrologic responses to spatio‐temporal characteristics of storms using a Dynamic Moving Storm generator     

Shang Gao  Zheng N. Fang 《水文研究》2019,33(21):2729-2744

A synthetic storm generator—Dynamic Moving Storm (DMS)—is developed in this study to represent spatio‐temporal variabilities of rainfall and storm movement in synthetic storms. Using an urban watershed as the testbed, the authors investigate the hydrologic responses to the DMS parameters and their interactions. In order to reveal the complex nature of rainfall–run‐off processes, previously simplified assumptions are relaxed in this study regarding (a) temporal variability of rainfall intensity and (b) time‐invariant flow velocity in channel routing. The results of this study demonstrate the significant contribution of storm moving velocity to the variation of peak discharge based on a global sensitivity analysis. Furthermore, a pairwise sensitivity analysis is conducted to elucidate not only the patterns in individual contributions from parameters to hydrologic responses but also their interactions with storm moving velocity. The intricacies of peak discharges resulting from sensitivity analyses are then dissected into independent hydrologic metrics, that is, run‐off volume and standard deviation of run‐off timings, for deeper insights. It is confirmed that peak discharge is increased when storms travel downstream along the main channel at the speed that corresponds to a temporal superposition of run‐off. Spatial concentration of catchment rainfall is found to be a critical linkage through which characteristics of moving storms affect peak discharges. In addition, altering peak timing of rainfall intensity in conjunction with storm movement results in varied storm core locations in the channel network, which further changes the flow attenuation effects from channel routing. For future directions, the DMS generator will be embedded in a stochastic modelling framework and applied in rainfall/flow frequency analysis.  相似文献   

中国旅游业发展生态负荷空间差异综合评价     

杨建明 《地理研究》2010,29(5):830-840

旅游生态负荷是指特定地域空间旅游业发展对自然生态系统施加的压力,是旅游人地关系的具体体现。基于对旅游生态负荷现象诱发因素的分析,从旅游者压力、旅游交通负荷和旅游建筑性侵害3个方面寻找人口密度、旅游密度、千人客车拥有量、公路网密度、旅游饭店床位密度、旅游森林负荷6个相关指标,通过模型的构建,对中国旅游生态负荷的省际差异进行综合评价。研究结果表明:中国旅游生态负荷在空间分布上具有沿海大于内陆、东南部大于西北部的总趋势,其中旅游生态负荷最高的地区位于中东部沿海。针对中国旅游生态负荷的空间差异,采取相应的策略与措施,是保证中国旅游业可持续发展的关键。  相似文献   

固定带宽滤波对InSAR图像对相关性影响的定量分析     

郭春生  朱兆达 《遥感学报》2006,10(6):864-868

讨论了干涉合成孔径雷达（InSAR）成像处理中基线解相关系数的频率函数，分析了在距离向压缩过程中频谱窗函数对InSAR图像对相关性的影响，通过定义干涉图距离向幅度谱函数的等效带宽来描述地形起伏，推导出了等效带宽和InSAR图像对相关性之间的关系式。据此给出了在不同等效带宽情况下（相当于不同地形起伏条件下），固定带宽滤波对InSAR图像对相关性的影响。最后的实验结果验证了上述分析的正确性。  相似文献   

铜陵狮子山矿田大团山铜（钼） 矿床流体包裹体研究   总被引：1，自引：0，他引：1       下载免费PDF全文

杨小男  徐兆文  王云健 《高校地质学报》2016,22(3):413

大团山铜（钼） 矿床是安徽铜陵狮子山矿田内较为典型的岩浆热液叠加型铜钼矿床,其成因与早白垩世大团山石英 二长闪长岩有密切关系。系统采集硫化物阶段的矿化石英脉并经岩相学显微观察发现,石英中捕获有大量的流体包裹体, 主要分为三种类型,即富气相（Ⅰ型）、富液相（Ⅱ型） 的两相水溶液包裹体和含子晶的三相水溶液包裹体（Ⅲ型）。显微 测温研究表明,流体包裹体的均一温度统计峰值分别出现在375~405°C和285~315°C之间,流体盐度的统计峰值出现在5.0 wt.%~10.0 wt.% NaCl eq.之间。激光拉曼探针分析表明,流体包裹体的气相成分以水蒸汽为主,含有少量CO2和CH4。流体 氢、氧同位素组成呈岩浆流体特征。研究表明,大团山铜（钼） 矿床的成矿流体主要来源于岩浆流体,在成矿过程中经历 了相态变化,沸腾的流体体系受到了不均匀捕获。结合前人研究成果,狮子山矿田内早白垩世叠加改造型流体表现出同源 特征,在物理化学演化方面具有一定规律性,流体的多次沸腾作用很可能对成矿元素的分配、迁移与沉淀起到了重要作用。  相似文献   

带信任度模糊评判在矢量地图数据质量中的应用     

范玉茹  隋立芬  马莉 《海洋测绘》2012,(1):32-34

分析了矢量地图数据质量元素,针对现有的质量模糊综合评判失效问题进行了探讨;在此基础上,运用带信任度的模糊综合评判方法对矢量地图数据进行质量评判,较好地解决了评判过程中的失效问题,提高了评判效率以及评判结果的可靠性。  相似文献   

Rickettsia-like organism infection associated with mass mortalities of blood clam, Tegillarca granosa, in the Yueqing Bay in China     

ZHU Zewen  XU Ting  HE Zhongyang  WU Xinzhong  WU Liuji  MENG Qingguo  HUANG Jiaqing 《海洋学报(英文版)》2012,31(1):106-115

A series of mass mortalities of the cultured blood clam, Tegillarca granosa, occurred in the Yueqing Bay of China from 2005 to 2009. An obligate intracellular prokaryote, designated as rickettsia-like organism (RLO), was frequently found in the moribund or dead blood clam sample during ultrastructural examination. These organisms were usually round, ellipsoid or occasionally dumbbell-shaped, ranged from approximately 0.28 to 0.71 μm in size and had a trilaminar cell wall. Two reproductive modes of organisms, transverse binary fission and budding, were observed. The organisms were able to form eosinophilic inclusions. Most inclusions were found within epithelial and connective tissues of the mantle, gills and digestive tube. The biological and morphological characteristics indicate that these organisms may belong to the family Rickettsiaceae. RLOs exhibited significant pathogenicity. Cytopathological examinations revealed extensive necrosis and destruction in the infected cell. The degree of tissue destruction was positively related to the number of RLO inclusions in the tissues, and the cytopathological effects were positively related to the number of intracellular RLO. RLOs and their inclusions were discovered throughout different disease areas and in different time periods. The infection intensity of the RLOs was positively correlated with the mortality rate of clams. Therefore, RLO infection might be associated with mass mortalities of cultured blood clams in the Yueqing Bay.  相似文献   

Geochemistry of fluid inclusions from Linglong gold deposit in Shandong，China     

ZHAO Yongyue  WANG Li  YANG Heting 《世界地质(英文版)》2012,15(1):26-34

By means of microscopy and laser Raman spectroscopy,the authors studied the fluid inclusions in petrography.The results show that there exist three-phase CO2 -bearing and two-phase aqueous inclusions in gold ore;the fluid of NaCl-H2O--CO2 system went through immiscibility in ore-forming process.Ore-forming fluids were of low salinity(0.82%-5.40%NaCleqv),low density(0.54-0.93 g/cm3);mineralization tempera-ture were concentrated in 320℃--340℃,with ore-forming pressure in 62-126 MPa and mineralization depth in 6.34-9.35 km.The fluid inclusions in quartz are generally characterized by a small amount of CO2 and N2.Combined with recent results of the isotopic analysis for fluid inclusions and dating data,it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water.The genetic type was mesothermal gold deposits involved by mantle-derived fluids.  相似文献   

基于多卫星平台永久散射体雷达干涉提取三维地表形变速度场   总被引：2，自引：0，他引：2       下载免费PDF全文

刘国祥  张瑞  李陶  于冰  李涛  贾洪果  聂运菊 《地球物理学报》2012,55(8):2598-2610

永久散射体雷达干涉(PSI)技术及其应用于区域地表形变监测已成为雷达遥感领域的研究热点之一.使用单一卫星平台所获取的单侧视SAR影像时间序列进行PSI分析,仅能获取沿雷达视线(LOS)方向的一维地表位移信息.本文提出了基于多平台永久散射体雷达干涉提取三维地表形变速度场的模型与算法,其基本策略是:首先针对每一卫星平台的SAR影像时间序列进行PSI分析,并计算各地面目标沿LOS向的位移速度值,然后联合各平台所对应的LOS向位移速度值进行建模,并基于最小二乘方法解算各地面目标的三维位移速度分量.实验选取天津市西北部作为测试区,使用2007—2010年所获取的39幅TerraSAR-X影像、23幅ENVISAT ASAR影像和16幅ALOS PALSAR影像进行分析,经联合解算得到了该测试区域的垂直位移速度场以及南北向和东西向水平位移速度分量.与地面水准和已有GPS观测结果对比分析表明:多平台PSI的垂直位移速度场精度可达毫米级,而其水平位移速度分量与已有GPS结果基本一致.多平台PSI分析无需引入任何外部形变参考信息,便可以实现形变场的偏差校准和三维形变场的恢复.  相似文献   

CH4-H2O体系流体包裹体均一过程激光拉曼光谱定量分析   总被引：6，自引：2，他引：4  

陈勇周瑶琪  刘超英颜世永 王强 《地学前缘》2005,12(4):592-596

对南黄海盆地二叠纪地层中某石英脉中的CH4-H2O体系流体包裹体均一过程进行了激光拉曼光谱定量分析。利用甲烷与水的拉曼峰面积比值计算不同温度下流体包裹体中水溶液相中甲烷的浓度,除了在100℃附近出现最小值,随温度增加甲烷浓度呈指数增大。包裹体在214℃完全均一,均一时甲烷的浓度为0·1347mol/L。同时利用甲烷的拉曼特征对流体包裹体均一过程的内压变化作了分析。压力变化可以分为三个区间:19~100℃,随温度升高压力增大;100~150℃压力随温度升高减小;150℃之后压力迅速增大。均一温度下的内压为21·92MPa。流体包裹体内压的变化主要是由甲烷溶解行为和封闭体系的热力学特征决定的。实验表明激光拉曼光技术可以作为定量分析含甲烷流体包裹体的一种有效方法。  相似文献