基于灰色支持向量机残差修正模型的地面沉降量预测     

宁志杰 《地质与勘探》2021,57(3):614-620

沉降现象在各地区普遍发生,地面沉降量预测越来越受到重视。本文通过结合灰色(GM(1,1))预测模型和支持向量机(SVM)模型各自的优点,建立灰色支持向量机(GM(1,1)-SVM)残差修正模型,在突出时间序列发展趋势影响的同时降低序列中异常值的消极作用。以某高层建筑的18次地面沉降量数据为实例,检验GM(1,1)-SVM模型的预测效果。结果表明:相对单一的GM(1,1)沉降量预测模型,GM(1,1)-SVM模型相对误差小,预测精度高,对地面沉降量预测有一定指导意义。  相似文献   

水稳定同位素示踪的冰川流域水文模拟及不确定性研究     

何天豪  高红凯  李向应  韩添丁  贺志华  张志才  段峥  刘敏  丁永建 《冰川冻土》2021,43(4):1130-1143

水文模拟不确定性长期以来是制约寒区水文发展的瓶颈问题。水稳定同位素示踪为认识冰川流域径流过程提供了重要“指纹”信息,但仍缺乏有效模型将该信息与冰川水文模型耦合,而且同位素信息对冰川流域水文模型不确定性的约束效果也有待检验。将水稳定同位素信息（δ¹⁸O）与冰川流域水文模型FLEX^G相耦合,实现对冰川流域水稳定同位素和径流过程的耦合建模（FLEX^G-iso）,并在乌鲁木齐河源1号冰川流域进行模拟检验和径流分割。结果表明：模型不仅对2013—2016年径流过程有良好的模拟效果,还可以重现水稳定同位素、冰川物质平衡等重要过程。利用水稳定同位素这一辅助数据,提高了模型参数的识别能力,减少了模拟过程中各水源的相互妥协效应和不确定性范围。2013—2016年1号冰川断面径流32%~34%来自融雪,48%~51%来自融冰,0%~7%来自地下水,12%~15%来自降雨径流。水稳定同位素对雪和冰川相关中间过程有明显的约束能力,原有模型对融冰贡献的模拟偏高约7%。FLEX^G-iso模型的建立有助于推动寒区水文学理论和方法的发展,以及寒区水资源、生态环境保护等相关决策制定。  相似文献   

螺杆钻进工艺在青海共和干热岩GR1钻井中的应用          下载免费PDF全文

谭现锋  王景广  郭新强  段隆臣 《探矿工程》2021,48(2):49-53

本文重要介绍了转盘(顶驱)+螺杆钻具复合钻进工艺在干热岩钻井中的应用。为进一步提高干热岩钻井施工效率和减少孔内事故,在青海共和干热岩GR1井进行了转盘+螺杆钻具复合钻进应用,根据现场高温井况下螺杆钻具的工作特性,改进优选了螺杆钻具的耐高温橡胶和转子定子的配合间隙,是螺杆钻具复合钻进工艺在深孔高温干热岩钻孔(孔深3705m,孔底温度236℃)施工的首次成功尝试,并取得了良好效果,经受住了硬岩和高温的考验,为进一步改进螺杆钻具在高温井况下的应用提供了宝贵的现场施工经验,也将为我国干热岩科学钻探与深部地热资源勘探提供新的技术支撑。  相似文献   

Sentinel-1卫星合成孔径雷达获取第一幅台风图像   总被引：2，自引：2，他引：0  

LI Xiaofeng 《海洋学报(英文版)》2015,34(1):1-2

In this note, we present the first Sentinel-1 synthetic aperture radar(SAR) typhoon image acquired in the northwest Pacific on October 4, 2014. The eye shape and sea surface wind patterns associated with Typhoon Phanfone are clearly shown in the high-quality SAR image. SAR winds retrieval procedure was given but the actual wind estimates will only be available after the European Space Agency(ESA) releases the official calibration coefficients in order to accurately derive the SAR-measured normalized radar cross section. This study demonstrates the advantage of Sentinel-1 SAR with regards to imaging fine scale typhoon patterns on the sea surface beneath storm clouds. This paper also advocates the use of Sentinel-1 SAR data that is made freely and openly available worldwide for the first time in civilian SAR history.  相似文献   

环介导等温扩增联合横向流动试纸条快速检测扁浒苔(Ulva compressa)的研究   总被引：2，自引：1，他引：1  

陈先锋  周前进  王瑞娜  段维军  苗亮  陈炯 《海洋与湖沼》2015,46(4):819-827

本研究将环介导等温扩增技术(loop-mediated isothermal amplification,LAMP)与横向流动试纸条(lateral flow dipstick,LFD)的可视化检测方法结合,建立了扁浒苔(Ulva compressa)的LAMPLFD快速检测技术。该方法以扁浒苔的内转录间隔区(ITS1-5.8S-ITS2)序列为检测靶标,设计了3对特异性引物(其中,上游内引物由生物素标记)和1条异硫氰酸荧光素标记的探针。结果表明,LAMP最适反应温度为63°C,扩增时间为60 min,从核酸扩增到LFD结果判读需70 min。利用LAMP-LFD可特异性检出扁浒苔,对浒苔、曲浒苔、缘管浒苔和孔石莼等石莼属绿藻以及塔玛亚历山大藻、无纹环沟藻、东海原甲藻、锥状斯克里普藻和赤潮异弯藻等常见微藻的检测结果为阴性。该方法最低可检测到0.1 pg的扁浒苔基因组DNA,是以Uco ITS-F3和Uco ITS-B3为特异性引物的PCR方法的100倍。对实际样品的检测结果表明,LAMP-LFD方法检测扁浒苔与传统的形态学观察的结果一致。因此,该方法可快速、特异地检测出扁浒苔,而且操作简单,仪器设备依赖性低,有潜力成为扁浒苔现场检测的常规技术手段。  相似文献   

A creep model for compacted loess based on 1D oedometer testEI北大核心CSCD     

Ge Miao-miao  Li Ning  Zheng Jian-guo  Zhang Ji-wen  Zhu Cai-hui 《岩土力学》2015,(11):3164-+

A series of long-term 1D oedometer test on compacted loess has been conducted using a high pressure consolidometer. It is found that the compacted loess has remarkable creep deformation and the proportion of the creep deformation in total deformation can come up to 6%-23%. The creep deformation proportion goes higher as the water content of the sample increases and the compaction degree reduces. And the creep deformation proportion decreases with the increase of stress level. A nonlinear creep model, which can well describe the rules of post-construction settlement of compacted loess, is proposed. The validity of model is verified by comparing the results from proposed model with those from the layer-wise summation method. The proposed model is employed to examine the variation law of the post-construction settlement under the conditions of the different water contents and compaction degrees. It is found that there exist logarithmic relationships between the post-construction settlement and the compaction degree/water contents. Supposing the velocity of the post-construction settlement v<0.1 mm/d is the stabilized standard, the high embankment settlement trends to be stable in 200 to 650 days after construction. The higher the compaction degree is, the lower the water content is, the longer the time up to stable required is.  相似文献   

PEPSI: The high‐resolution échelle spectrograph and polarimeter for the Large Binocular Telescope     

K.G. Strassmeier  I. Ilyin  A. Jrvinen  M. Weber  M. Woche  S. I. Barnes  S.‐M. Bauer  E. Beckert  W. Bittner  R. Bredthauer  T. A. Carroll  C. Denker  F. Dionies  I. DiVarano  D. Dscher  T. Fechner  D. Feuerstein  T. Granzer  T. Hahn  G. Harnisch  A. Hofmann  M. Lesser  J. Paschke  S. Pankratow  V. Plank  D. Plüschke  E. Popow  D. Sablowski  J. Storm 《Astronomische Nachrichten》2015,336(4):324-361

PEPSI is the bench‐mounted, two‐arm, fibre‐fed and stabilized Potsdam Echelle Polarimetric and Spectroscopic Instrument for the 2×8.4 m Large Binocular Telescope (LBT). Three spectral resolutions of either 43 000, 120 000 or 270 000 can cover the entire optical/red wavelength range from 383 to 907 nm in three exposures. Two 10.3k×10.3k CCDs with 9‐µm pixels and peak quantum efficiencies of 94–96 % record a total of 92 échelle orders. We introduce a new variant of a wave‐guide image slicer with 3, 5, and 7 slices and peak efficiencies between 92–96 %. A total of six cross dispersers cover the six wavelength settings of the spectrograph, two of them always simultaneously. These are made of a VPH‐grating sandwiched by two prisms. The peak efficiency of the system, including the telescope, is 15 % at 650 nm, and still 11 % and 10 % at 390 nm and 900 nm, respectively. In combination with the 110 m² light‐collecting capability of the LBT, we expect a limiting magnitude of ≈20th mag in V in the low‐resolution mode. The R = 120 000 mode can also be used with two, dual‐beam Stokes IQUV polarimeters. The 270 000‐mode is made possible with the 7‐slice image slicer and a 100‐µm fibre through a projected sky aperture of 0.74″, comparable to the median seeing of the LBT site. The 43 000‐mode with 12‐pixel sampling per resolution element is our bad seeing or faint‐object mode. Any of the three resolution modes can either be used with sky fibers for simultaneous sky exposures or with light from a stabilized Fabry‐Pérot étalon for ultra‐precise radial velocities. CCD‐image processing is performed with the dedicated data‐reduction and analysis package PEPSI‐S4S. Its full error propagation through all image‐processing steps allows an adaptive selection of parameters by using statistical inferences and robust estimators. A solar feed makes use of PEPSI during day time and a 500‐m feed from the 1.8 m VATT can be used when the LBT is busy otherwise. In this paper, we present the basic instrument design, its realization, and its characteristics. Some pre‐commissioning first‐light spectra shall demonstrate the basic functionality. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

资源一号02C卫星数据在北京岩溶水资源勘查评价工程中的应用   总被引：2，自引：0，他引：2  

程洋  童立强  郭兆成  莫源富  纪轶群 《国土资源遥感》2015,(2):183-189

以资源一号02C(ZY1-02C)卫星数据为数据源,以GIS为数据处理平台,以遥感地质理论和水文地质理论为指导,将遥感技术应用于北京岩溶水资源勘查评价工程中。通过水文地质遥感解译和综合分析,优选了一处新的供水水源地,建立了适用于北方岩溶区的含水岩组和泉点的遥感解译标志,提出了基于GIS的水文地质分析方法,扩展了国产资源卫星数据的应用领域。  相似文献   

基于MODIS数据的湖北省油菜种植分布信息提取   总被引：1，自引：0，他引：1  

王凯  张佳华 《国土资源遥感》2015,(3)

MODIS归一化差值植被指数(MODIS-normalized difference vegetation index,MODIS-NDVI)时间序列产品能够连续反映植被的覆盖情况,是农作物遥感测量的重要数据源。为研究基于MODIS数据的油菜种植分布信息提取技术,选取湖北省为研究区,利用2008—2013年75个时相的MODIS-NDVI时序数据,结合农作物物候和地面调查样本等辅助资料,通过建立油菜种植面积提取模型,采用多次阈值比较方法提取了2009—2013年湖北省油菜种植分布信息,与统计数据比较,总体提取精度为85%左右。最后利用环境小卫星HJ-1A CCD数据进行精度验证,证明了MODIS-NDVI时序数据及本文方法在油菜种植面积提取中的可靠性,对掌握油菜种植面积和产量信息、加强农业生产管理、调整农业结构及辅助政府有关部门制定科学合理的农业政策具有重要意义。  相似文献   

基于扫描统计的甲型H1N1流感聚集性分析     

姚欣  夏天琦  翁敏 《测绘工程》2015,(10):56-58

扫描统计已被广泛应用于地域性疾病的聚集性检测,且可检测这种聚集的差异显著性。文中使用扫描统计的方法,通过对2009~2012年全国各省的甲型H1N1流感数据进行时空扫描以及逐年的空间扫描,生成高发病率地区和低发病率地区聚类,并通过叠置分析反映各个地区归入聚类的频次。利用专题地图和统计表分析甲型流感在2009~2012年中的爆发情况和趋势,并对结果进行客观的分析。  相似文献