面向遥感的GNSS反射信号接收处理系统及实验   总被引：3，自引：0，他引：3  

李伟强  杨东凯  李明里  张其善 《武汉大学学报(信息科学版)》2011,36(10):1204-1208

提出了一种新的GNSS-R信号接收处理系统（GNSS-Rreceiver system,GRrSv.2）的结构及信号处理方法。该系统可同时针对直射和反射的GNSS信号协同处理,并输出可配置延迟和多普勒的二维相关值矩阵。为了验证系统的性能,进行了针对海洋和陆地遥感的机载和岸基验证实验,并给出了初步的实验结果。  相似文献   

淤泥质海岸螺旋桩的轴向承载特性研究          下载免费PDF全文

赵星婕  王忠岱  吴伟强  谢立全 《海洋技术学报》2022,41(2):85-92

海上风电高压海缆登陆后往往需要跨越平原淤泥质海岸,高压电缆排管易发生不均匀沉降而裂损,螺旋桩因施工方便、速度快,可用于不均匀沉降的应急控制。螺旋桩的承载力是其工程应用的重要设计内容,其桩型参数的改变,对极限抗压承载力有着较大影响。本文结合工程实践,通过开展抗压承载力数值模拟,研究分析了螺旋桩叶片宽度、叶片个数、叶片间距...  相似文献   

基于AHP和GIS的中心村建设选址研究——以巩义市西村镇为例   总被引：1，自引：0，他引：1  

张艳粉  刘科问  陈伟强 《地域研究与开发》2013,32(3)

为了解决新农村规划中的核心问题——中心村建设选址,以巩义市西村镇为研究对象,采用第二次全国土地调查数据,运用AHP法确定指标权重,建立村庄潜力评价指标体系;通过GIS空间分析得到各村评价参数;运用多因素综合分析计算村庄潜力评价综合分值;运用聚类分析确定村庄分级;最后用Voronoi图分割势力范围,验证村庄空间布局的合理性.结果表明:(1)影响村庄潜力的主要因素有区位条件、村庄规模、经济发展水平、服务设施完善度及村庄集聚度;(2)西村镇村庄可以划分4个等级层次;(3)中心村类型主要分为规模经济型和集聚经济型;(4)运用AHP和GIS模拟出的村庄空间布局科学合理,可为新农村规划提供依据.  相似文献   

基于MODIS数据的近8年长三角城市群热岛特征及演变分析   总被引：10，自引：2，他引：8  

葛伟强  周红妹  杨何群 《气象》2010,36(11):77-81

利用MODIS hdf数据来反演地表温度,首先通过数据挑选少云覆盖图像,再经多波段综合法去云,用近8年的MODIS历史资料选择劈窗算法反演计算给出了长三角平均地表温度分布图,以长三角作为区域整体研究热岛效应,分析了城市群热岛分布特征,指出主要城市热岛分布呈"Z"字型分布格局。长三角地区热岛强度季节变化是夏季最强,春季次之,秋冬季除少数地区为较强热岛外,大部分地区都显示为弱热岛或无热岛。采用GIS地理统计方法比较16城市的强热岛面积分布,分析了2001—2008年夏季各城市热岛强度的年际变化趋势。  相似文献   

东昆仑中灶火地区中三叠世花岗岩LA-ICP-MS锆石U-Pb定年、岩石成因及构造意义     

菅坤坤  朱云海  王利伟  高峰  刘向东  何元方  袁璋  陈继平  高维强 《地质论评》2017,63(3):659-676

东昆仑中灶火地区的石英闪长岩—花岗闪长岩—二长花岗岩具有连续的成分变化。岩石具有中等到高的Si O_2含量(58.15%~71.12%),适度的高铝和全碱含量,为中—高钾钙碱性的准铝质Ⅰ型花岗岩。岩石相对富集大离子亲石元素和轻稀土元素,并亏损高场强元素,显示出弧岩浆岩的一般地球化学特征。锆石地质年代学分析获得石英闪长岩和花岗闪长岩的锆石结晶年龄约为243Ma,表明本文研究的花岗岩类为中三叠世岩浆岩。结合地质、地球化学研究,这套花岗岩形成于陆缘弧环境,是古特提斯洋俯冲晚期的岩浆记录。其成因为俯冲动力学背景下,幔源岩浆的底侵作用导致下地壳部分熔融,随后壳源熔体与幔源熔体发生不同程度的混合形成母岩浆,又经历了较高程度的结晶分异形成石英闪长岩—花岗闪长岩—二长花岗岩序列。  相似文献   

The Cu isotopic signature of granites from the Lachlan Fold Belt,SE Australia     

Weiqiang Li  Simon E. Jackson  Norman J. Pearson  Olivier Alard  Bruce W. Chappell 《Chemical Geology》2009,258(1-2):38-49

This contribution reports our preliminary work to determine Cu isotope ratios for various granite rocks and examine the Cu isotope systematics within granite suites. A chemical procedure, modified from Maréchal [Maréchal, C.N., Télouk, P. and Albarède, F., 1999. Precise analysis of copper and zinc isotopic compositions by plasma-source mass spectrometry. Chemical Geology, 156(1–4): 251–273.], was used to separate Cu from rock matrix. Quantitative recovery (100.6 ± 1.6%), with a low total procedural blank (2.65 ± 0.66 ng) for Cu, has been achieved, allowing Cu isotopic measurements on samples with as little as 10 ppm Cu. The Cu isotope ratios (δ⁶⁵Cu relative to NIST SRM 976) of 32 rock samples, ranging from mafic to felsic compositions, from 3 batholiths (2 I-type, 1 S-type) from the Lachlan Fold Belt in southeastern Australia, vary from ? 0.46‰ to 1.51‰. Most of them cluster around zero, with mean values for the I-type and S-type granites of 0.03 ± 0.15‰ and ? 0.03 ± 0.42‰ (2 sigma) respectively. These data, together with Cu isotope ratios of two loess samples, provide preliminary evidence that the baseline Cu isotopic composition of the crystalline part of upper continental crust is close to zero. The tight clustering of Cu isotope ratios of rocks from the I-type suites suggests that high-temperature magmatic processes do not produce significant Cu isotope fractionation. However, two granites with abnormally heavy Cu isotope signatures (up to 1.51‰) appears to be the result of localized hydrothermal alteration. Measurable variation in Cu isotopic composition of the S-type granite may reflect isotopic heterogeneity in the sedimentary source region as a result of redox processes or may be due to hydrothermal overprinting. Thus, Cu isotope geochemistry may be a useful tracer for studying hydrothermal alteration and source heterogeneity of granitic rocks.  相似文献   

Distribution Patterns of Remaining Hydrocarbons Controlled by Reservoir Architecture of Distributary Channel with Different Channel Style: S2 Formation of Songliao Basin, China     

LI Weiqiang  YIN Taiju  ZHAO Lun  ZHAO Liangdong 《《地质学报》英文版》2017,91(Z1):129-130

<正>1 Introduction Reservoir architecture analysis of distributary channel of Daqing oilfield has drawn consistent interest among development geologists and petroleum engineers over the last decade(Lv et al.,1999;Zhou et al.,2008;Zhang et  相似文献   

Variation of wave velocity and thermal conductivity of concrete after high-temperature treatment     

Qiang Sun  Jishi Geng  Weiqiang Zhang  Chao Lü 《Environmental Earth Sciences》2017,76(2):88

This paper studies the variation of mass, density, wave velocity and thermal conductivity of concrete after high-temperature heat treatment. The range of temperature to which the concrete specimens are exposed is 25–900 °C, in a heating furnace. The results are summarized as follows: three temperature ranges (20–300 °C, 300–600 °C and above 600 °C) corresponding to the moisture vaporization (i.e., adhered water, combined water or crystal water), decomposition of some minerals (i.e., Ca-hydroxide, Mg-hydroxide) and Ca-carbonate are obviously evident. The physical properties of concrete specimens change most significantly within the temperature range above 300 °C, which may be attributed to the transformation of concrete minerals. Moreover, within the temperature range of 300–900 °C, especially between 400 and 600 °C, the concrete structure has significant chemical changes basing on the variations of surface features, ultimately making the number and width of cracks and mass loss level increased, as well as the wave velocity and thermal conductivity changed.  相似文献   

雅鲁藏布江流域气温变化特征及趋势分析     

宋敏红  马耀明  张宇  李茂善  马伟强  孙方林 《气候与环境研究》2011,16(6):760-766

通过分析1980～2005年间雅鲁藏布江流域7个气象台站平均的气温变化趋势和气候系数变化,并进一步分析了1960～2005年间该流域中游日喀则站和下游林芝站气温的变化趋势,研究了该流域气温变化对全球变暖的响应.结果表明,1980～2005年间雅鲁藏布江流域的气温呈现逐渐升高的趋势,尤其是夜间气温和冬、春季气温的升高更显著,而且该流域变暖幅度高于整个高原的平均增幅,因此该流域对全球变暖的响应程度也较整个高原更为显著;而该流域中游地区的增温幅度要明显高于下游地区的,即该流域中游地区的增暖较下游地区的更为显著.  相似文献   

北特鲁瓦油田裂缝成因和产状对储层物性的影响     

赵伦  李长海  李建新  王淑琴  李伟强  孙猛 《地质论评》2019,65(Z1):267-268

正随着国内大部分油田进入开发中后期,海外油气业务正日益成为当今中国保证能源安全的重要途径之一。北特鲁瓦油田是中石油在哈萨克斯坦重要的作业区块之一,属于典型的碳酸盐岩储层。北特鲁瓦油田KT-Ⅰ层是主力油气产层,裂缝极其发育且十分复杂,发育了多成因多产状的裂缝,尤其非构造缝极其发育,使裂缝预测十分困难。一方面裂缝的存在提高了早期该油田油气产能,另一方面  相似文献