巩义市优质小麦农业气候资源分析

利用1961～1990年气象资料和小麦生产资料,分析了巩义市小麦生育期的光能资源、热量资源、水分资源及产量波动的气象原因,并确定了不同年型的适宜播种期.     

多维地震下考虑不同破坏准则的输电塔-线体系倒塌分析

研究了基于不同失效准则多维地震激励下输电塔-线体系的倒塌。根据实际工程,运用ABAQUS有限元分析软件,考虑材料非线性和几何非线性,建立了包含两基输电塔与3跨输电线的大跨越输电塔-线体系三维有限元模型。提出了2种不同的杆件失效准则,采用用户材料子程序,基于动力显式分析方法,研究了大跨越输电塔-线体系在3条典型天然地震波作用下考虑不同失效准则的倒塌机理,并对输电塔的杆件失效、节间位移角以及相对薄弱位置进行了分析。分析结果可以为大跨越输电塔-线体系的抗震设计提供参考。     

BDS中长距离非差实时动态厘米级定位算法

针对BDS常规实时动态定位(RTK)中,随着流动站与参考站间的距离增加,大气延迟误差的空间相关性大大降低,影响了整周模糊度的快速解算和流动站位置信息的解算精度问题。该文研究了一种基于非差观测误差的BDS中长距离常规RTK定位算法,采用非差误差改正方法为流动站提供误差改正,利用参考站的非差误差改正数以单颗卫星为对象进行误差改正。对电离层延迟误差和相对天顶对流层延迟误差进行参数估计,处理电离层延迟误差和对流层延迟误差的影响。最后通过BDS实测数据对该算法进行了算法验证和结果分析。实验结果表明,该算法可以实现BDS中长距离常规RTK的快速定位,并获得厘米级定位精度。     

微量元素在植物光谱中的响应机理研究

微量元素与植物光谱特征的研究是光学遥感定量化研究的重要内容之一。本研究利用高光谱地面光谱仪（GER）在湖南黔阳地区不同地质地球化学背景下的同一垂直剖面上分别测量了岩石、土壤植物（林灌草）的反射光谱曲线和植物叶片的8种微量元素含量。通过研究微量元素Fe,Mn,Cu,Zn,Co,Cr,Mo,B与植物（包括林灌草）反射光谱间的相关性研究发现Co的含量与植物光谱绿区（0．56μm附近）反射率存在强的负相关，Mn,B,Mo和Zn分别在可见光、近红外、短波红外存在较好的相关性和光谱响应。     

基于CORS的GPS拟合高程技术在城市管网控制测量中的应用

长春市已经建立的连续运行卫星定位参考站系统能够提供实时高精度平面位置的定位,但是,高精度的似大地水准面精化技术未投入实际应用,使得空间第三维信息的获取未做到简洁、高效。如果将CORS技术和GPS拟合高程技术相结合,将能实现真正意义的空间高精度实时三维动态定位,从而代替繁重的几何水准测量。     

机载多光谱影像语义分割模型在农田防护林提取中的应用

农田防护林是农田生态系统的屏障,其健康状况的监测与评估在我国北方农田林网管理中尤为重要。本文以新疆生产建设兵团第三师51团为研究区,使用复合翼无人机CW-20搭载Micro MCA12 Snap多光谱相机获取农田防护林的多光谱影像,经辐射校正、裁剪等预处理,通过优选有效特征和模型比较,提出农田防护林提取的有效方法。首先,基于原始12波段,依据相关性系数矩阵和最佳指数因子（Optimum Index Factor,OIF）选取最优3波段和植被指数特征进行组合,构建8种农田防护林提取方案;然后,通过建立语义分割Deeplabv3+模型进行精度评价,得到最优3波段组合6（波长710 nm）、8（波长800 nm）、 11（波长900 nm）波段为最佳特征组合;最后,以最优3波段为基础,将Deeplabv3+模型与U-Net、ENVINet5模型进行对比分析。结果表明：Deeplabv3+模型能够更深层次的挖掘光谱中潜在的信息,相比其他模型,能够较好地处理正负样本不均衡问题,获得最高MIoU值85.54%,比U-Net、ENVINet5的MIoU值则分别高出21.21%、27.19%。该研究结果可为基于多光谱遥感影像的语义分割在农田防护林提取及健康状况监测的应用提供借鉴和参考。     

An efficient method of noroviruses recovery from oysters and clams

Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish. This study aimed to select a simple, rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR. Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams, respectively, were compared, of them, the method involving proteinase K and PEG 8000 was found the most efficient. With this method, 9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams, respectively. This method was further used to detect NoVs in 84 oysters (Crassostrea gigas) and 86 clams (Ruditapes philippinarum) collected from 10 coastal cities in China from Jan. 2011 to Feb. 2012. The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84). All the detected NoVs belonged to genotype GII. The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.     

Source Evolution and Its Relationship to Climate Change Since the Middle–Late Pleistocene in Laizhou Bay,China

Through the geochemical analysis of two hundred-meters cores KD4 and ZK3 from Laizhou Bay,in this study,we determined the distribution law and controlling factors of the geochemical elements.We analyzed 24 elements with respect to their R factors and major principal components,which were combined with the source discrimination functions DFCr/Th and DFCa/Al to obtain the sediment source index and its variation with depth for this area.A comparison of the changes in climate indicators suggests a clear correlation between the source and climate changes.The results show that the Yellow River and surrounding short-term rivers are the main sediment sources in this area.The PC3 of the KD4 core and PC2 of the ZK3 core(e.g.,CaO,MnO,SiO2)exhibit significant variations and reflect the relative contributions of Yellow River sources.The deposition process can be divided into six stages:in Phase I(MIS 5c–MIS 5a),the Yellow River formed,and the composition of the Yellow River had a greater influence on the sedimentary composition of the study area.In Phase II(MIS 5a–MIS 3),the sediment sources of the Yellow River and the short-term streams in this area were wavering,with the sediments derived from short-term rivers playing a more important role.In Phase III(MIS 3),with a sharp drop in temperature,the study area was in the process of retreat,and the sediment source changed from the Yellow River to short-term rivers,after which the Yellow River source material remained the main sediment source for the region.A similar process occurred three more times in Phase IV(MIS 3–MIS 2),Phase V(MIS 2–MIS 1),and Phase VI(MIS 1).With changes in climate,especially during alternating sea-land phases,the sediment source varied in marine-terrestrial-marine phases,and the changes are observed as Yellow River source-surrounding provenance-Yellow River source.However,this process of change is not synchronized with the sea-land strata alternation.     

自发地理信息可信度及其评价

由于自发地理信息数据主要来源于志愿者上传,不可避免地存在数据质量缺乏保障等问题,故限制了其广泛应用。针对自发地理信息数据质量未知、参考数据难以获取等问题,本文引入了数据可信度的概念,从区域内用户信誉度之和与数据变化趋势2个方面对自发地理信息的可信度进行评价,将定性分析结果进行量化表达。首先,利用李纳斯定理计算区域内用户的信誉度之和获取数据质量的相关信息,以志愿者上传数据中保留的点所占比重作为志愿者的信誉度,构建了基于点统计的志愿者信誉度模型。接着,从数据量变化的趋势中获取数据的质量信息,通过计算研究区域内数据量的变化程度进行数据变化趋势度量。最后,以北京等地区OpenStreetMap数据作为实验对象,验证了方法的有效性。实验结果表明,利用该方法所得出的实验结果与基于参考数据的质量评价结果总体上保持一致。