三峡库区土门子滑坡变形破坏机制分析   总被引：3，自引：1，他引：2  

孙东晖  刘建磊 《岩土工程技术》2008,22(5):267-270

在研究土门子滑坡地质环境和变形特征的基础上,对滑坡的成因机制、变形破坏模式及起动机制进行了分析。结果表明,该滑坡为前缘牵引后缘平推式,现处于整体蠕动变形局部滑移阶段,持续强降雨是诱发其失稳破坏的主导因素,针对滑坡体可能沿多个剪出口发生变形破坏等特征、提出了相应工程防治建议,对指导该类工程的设计和施工具有参考意义。  相似文献   

叶面积指数间接测量方法   总被引：2，自引：0，他引：2  

阎广建  胡容海  罗京辉  穆西晗  谢东辉  张吴明 《遥感学报》2016,20(5):958-978

叶面积指数是对地遥感的关键参数。间接测量法快速高效,已广泛应用于叶面积指数的地面测量和遥感验证中,服务于众多行业和领域,表现为论文被引数远远大于发文数。从理论基础、代表算法、测量仪器、影响因素几个方面全面总结了叶面积指数间接测量方法的发展和现状,指出聚集/尺度效应、叶倾角分布、木质组分、地形效应是影响测量精度的关键因素,针对这些影响因素对未来发展方向进行了展望。  相似文献   

40年的跨越-中国航天遥感蓬勃发展中的“三大战役”     

顾行发  余涛  田国良  周上益  魏成阶  李娟  余琦  刘东晖  卫征  孟庆岩  徐辉  郭红  周翔  王春梅  臧文乾  黄祥志  高海亮  郑逢杰  刘苗  王栋  赵亚萌  魏香琴  孙源  李斌  廖戬  任芯雨 《遥感学报》2016,20(5):781-793

20世纪70年代末到80年代,中国多家单位大联合、大团结、大协作,开展了腾冲航空遥感试验、天津-渤海湾环境遥感试验和二滩水能开发遥感试验三项遥感科学试验,通过多学科交叉融合,提升了中国对遥感技术应用的认识,培养出一大批遥感科学技术人才和专家,取得了丰硕的科技成果和显著的社会经济效益。这3项试验成功地将遥感综合应用系统性地引入中国,标志着中国多领域遥感应用的起步,被称为中国遥感的"三大战役"。经过40年快速发展、积累酝酿、大胆创新、快速迭代,中国航天遥感应用迈过了几个重要阶段,正向战略性新兴产业方向发展。为顺应科技、经济、社会以及全球化发展战略的需求,中国适时实施了高分辨率对地观测系统重大专项、国家民用空间基础设施中长期发展规划和2030中国综合地球观测系统,进一步推进中国航天遥感应用从追赶国外先进技术到强化自主创新的转变,进入规模化、产业化和商业化发展阶段,可谓之为新"三大战役"。结合中国"一带一路"战略的大背景,通过新三大战役的实施,必将深化"走出去"战略,拓展全球服务能力,提升国际竞争力,向新的历史发展高度迈进。  相似文献   

Preliminary study of the retention mechanism of planktonic copepods in the Jiulong Estuary in China   总被引：1，自引：0，他引：1  

SHANG Xu  WANG Guizhong  LI Shaojing  GUO Donghui 《海洋学报(英文版)》2007,26(4):156-163

The horizontal and vertical distribution patterns of five planktonic copepods,Calanus sinicus, Acartia pacifica, Tortanus derjugini, Acartiella sinensis and Pseudodiaptomus poplesia, predominant in the Jiulong Estuary, were investigated from May 2003 to April 2004. The results showed that the distribution of these copepods was related to the tidal period but that each species had its own specific pattern. C. sinicus showed no tidal vertical migration behavior and was thought to be a non-resident species in this estuary. Among Acartia pacifica,T. derjugini,Acartiella sinensis, more individuals occurred in the surface than in the bottom waters during flood tide, and the pattern was reversed during ebb tide. The epibenthic copepod P. poplesia usually remained in the bottom waters in the upstream part of the estuary, but it displayed strong tidally-oriented vertical migration in the middle reaches of the estuary.Taking into account the hydrographic characteristics of the Jiulong Estuary,it was hypothesized that the planktonic copepods in this estuary had more or less adopted the mechanism of vertically migrating to the surface waters during flood tide in order to make use of the inflowing tide, and then sinking to the bottom during ebb tide to avoid being carried out of the estuary by net outflow.  相似文献   

多道瞬态面波法与微动法联合推断岩溶塌陷区覆盖层的结构和厚度分布     

张伟  甘伏平  梁东辉  韩凯  刘伟 《中国岩溶》2018,37(2):272-279

为了大尺度范围内获取岩溶塌陷典型调查区覆盖层的结构和厚度分布,采用多道瞬态面波法与微动法,对柳州市柳城县东泉公社幅岩溶塌陷重点调查区进行了野外观测,根据微动法提取的特征频率与地层厚度的关系,结合已知钻孔资料,得出覆盖层厚度与特征频率的函数关系,获取了覆盖层的厚度分布,根据面波的频散特性,得出覆盖层的横波速度分布,获取了覆盖层的结构分布,结合得出的覆盖层结构和厚度分布,推断出测区内发育4条断层或溶沟等局部构造。研究表明,利用微动法提取的特征频率和面波的频散特性,可以有效地推断出塌陷区覆盖层的结构和厚度分布。   相似文献   

The application of HVSR method in detecting sediment thickness in karst collapse area of Pearl River Delta,China   总被引：1，自引：0，他引：1  

Donghui Liang  Fuping Gan  Wei Zhang  Long Jia 《Environmental Earth Sciences》2018,77(6):259

The microtremor horizontal-to-vertical spectral ratio (HVSR, or H/V spectral ratio) method is an effective tool for detecting sediment thickness. Firstly, single-station microtremor measurements were taken beside 52 boreholes located in Pearl River Delta, China. Sediment thicknesses revealed by those boreholes range from 7.9 to 39.6 m. Then, those microtremor data were analyzed using HVSR method, and peak frequency of each site was extracted. According to those peak frequencies of HVSR and corresponding sediment thicknesses, the frequency-to-thickness fitting (f–Z) equation which is suitable for Pearl River Delta area was established. And this equation was compared with several fitting equations derived from different regions by other researchers. Finally, this fitting equation was applied in a collapse area in Guangzhou city to estimate site sediment thickness. Compared with data from five boreholes in this collapse area, the consistency between estimated sediment thickness and real value was relatively good. Karst sinkholes are generally located in regions where thickness of sediments is shallow. Therefore, the method described in this paper can provide support for delineating potential collapse areas.  相似文献   

准饱和多孔介质中地下水驱替速率、圈闭气体饱和度和准饱和渗透系数的关系     

程东会  李慧  王军  李爽  黄梦楠  马成龙  饶泽 《地学前缘》2022,29(3):256-262

圈闭有不连续、非流动和非混溶气体的含水层,被称为准饱和含水层。圈闭气体的存在会降低含水层的渗透性能,但准饱和渗透系数、圈闭气体饱和度和驱替速率之间的关系还没有完全被理解。本文通过室内砂性介质的驱替试验开展了圈闭气体饱和度、准饱和渗透系数和驱替速率三者相互关系的研究。研究表明,虽然总体上圈闭气体饱和度随驱替速率的增大而减小,但是在高驱替速率和低驱替速率分别出现了圈闭气体饱和度不随驱替速率变化的等值区间,该“台阶”型曲线可以采用与van Genuchten曲线类似的数学模型来表征,而砂性介质的准饱和渗透系数与圈闭气体饱和度之间呈简单的线性负相关关系。这两个经验模型说明可以用驱替速率定量估算准饱和渗透系数,该关系为利用驱替速率估算准饱和渗透系数提供了理论依据。上述准饱和水力学性质为深入理解准饱和地下水水流提供了依据。另外,驱替速率与圈闭气体饱和度的关系还表明,实验室测量完全饱和渗透系数时,应以大于初始毛细上升速率的速率进行饱和,以避免介质中的空气被水圈闭。  相似文献   

一种低动态高抖动环境下的GPS/INS紧组合方法     

徐爱功  刘韬  隋心  郝雨时  杨东辉  郭哲  王长强 《测绘科学》2018,(2):1-5,29

针对低动态高抖动环境下,影响GPS/INS紧组合精度的重要因素——惯性测量单元(IMU)数据中的噪声,该文提出利用小波降噪方法分离IMU数据中的噪声和有用信号以提高GPS/INS紧组合的精度。首先对IMU数据进行小波分解后得到的高频系数进行阈值量化处理,然后将GPS观测数据与降噪后的IMU数据进行GPS/INS紧组合解算,最终得到载体的导航信息。实例结果表明,该方法可以大幅提升GPS/INS紧组合的精度和稳定可靠性。  相似文献   

沈阳市农村土地承包经营权确权登记     

喻华  赵东辉 《北京测绘》2018,32(4):479-483

农村土地承包经营权确权登记,由县级政府行政主管部门组织实施。其核心内容是采集承包土地的地块、面积、空间位置及变化等信息,建立数据建库和管理系统,实现农村土地承包经营权信息管理、颁发土地承包经营权证书,依法赋予农民对承包地的占有、使用、收益、流转及承包经营权抵押、担保等权利,从而保障农民对承包土地的各项权益。结合沈阳市土地承包经营现状,设计先行、组织保障、测绘实施、数据建库等工作是实现沈阳市农村土地承包经营权确权信息管理的前提。  相似文献   

Review on snowmelt runoff simulation in mountain regions,Northwest China北大核心CSCD     

李晶  刘时银  张世强  陈仁升  赵求东  郭万钦  上官冬辉  王荣军  钟歆玥  尹振良  李弘毅 《冰川冻土》2022,44(3):1029-1040

Snowmelt runoff is a valuable water resource in Northwest China. In the past few decades, progress has been achieved in snowmelt runoff simulation in mountainous areas, including observation and simulation of snow melt process, improvement and development of distributed snow melt runoff model, and ability for application of snow melt runoff model with temporal and spatial distribution driving data. The development of interpolation algorithm, remote sensing and data assimilation technology provides data support for the widespread application of distributed snowmelt runoff model in northwest mountainous regions of China. Climate warming and economic and social development will further aggravate the contradiction between supply and demand of water resources in the arid regions of Northwest China, which requires higher precision and detail spatial and temporal resolution of snowmelt runoff simulation. Based on the progress and challenges on snowmelt runoff simulation in mountainous regions of Northwest China, following studies need more attention：the mechanism of snow accumulation and ablation, snow cover spatial and temporal distribution monitoring and high precision of snow distribution data acquisition, quantitative climate change impact on river basin snowmelt runoff. © 2022 The authors.  相似文献