基于吸收峰加权的岩矿光谱匹配方法研究   总被引：2，自引：0，他引：2  

黄婷婷  韦志辉  修连存  吴泽彬 《岩矿测试》2011,30(5):584-589

基于高光谱图像的矿物识别主要依赖于矿物的特征光谱曲线,但由于矿物普遍存在的同质多象和类质同象的现象,常常造成矿物识别误差.在矿物的光谱曲线描述中,吸收位置是一个非常重要的特征,它较好地反映了矿物的单个诊断性特征.文章在利用完全波形特征的基础上,加强了单个诊断性特征,提出了一种基于吸收峰加权的预处理技术.利用该技术并结合...  相似文献   

图割模型在卫星云图云检测中的应用   总被引：2，自引：0，他引：2  

费文龙  吕红  韦志辉 《南京气象学院学报》2012,35(4):502-507

提出一种基于图割模型的卫星云图云检测方法。利用FY-2C卫星云图的长波红外通道和可见光通道的云图提取了10个灰度特征和80个Gabor纹理特征,再用主成分分析方法（principal component analysis,PCA）降维到9个主成分。将这9个主成分构成的特征作为每个像素的特征,建立相似度矩阵,再利用改进的NormalizedCuts模型进行分割,将云图分成了晴空区域和有云区域。与地面观测结果相比,平均一致率达到86．51％,表明将Gabor纹理特征和灰度特征相结合并利用改进的Normalized Cuts模型对卫星云图云检测有比较好的效果。  相似文献   

中等传输距离下的无线功率传输链路第2部分:选择性工作方式     

Alessio De ANGELIS  Marco DIONIGI  Paolo CARBONE  Mauro MONGIARDO  车文荃  王清华  Franco MASTRI  Giuseppina MONTI 《南京气象学院学报》2017,9(1):73-81

对谐振感应式无线功率传输链路的3种不同的工作方式进行了讨论.第1种工作方式是输出恒定的电压或电流;第2种工作方式采用频率捷变操作,非常适合于不随耦合系数变化的应用场合;第3种工作方式实现负载独立工作并输出恒定的电压或电流.本文讨论并提出了不同情况下的解决方案和相关公式.最后通过实验对提出的理论进行了验证.  相似文献   

带有Le'vy噪声的中立型神经网络的反馈控制     

张贺  徐胜元 《南京气象学院学报》2018,10(6):676-680

针对延迟中立型神经网络系统,研究了反馈控制问题.考虑了带有Le''vy噪声的中立型神经网络,建立了一个适当的Lyapunov函数.通过Lyapunov分析方法并使用一般性Itô公式和LMI技术,得到了闭环系统的均方稳定性准则.最后,通过数值例子证实本文方法的有效性.  相似文献   

基于GPS的水下导航算法误差仿真研究     

赵辉  王昌明  何云峰 《海洋技术学报》2006,25(2):44-47

首先介绍了水下导航算法,采用GPS和水下参量测算相结合的方案,即当运行器在水下运行时,利用电子罗盘测量运行器的相对航向,水流传感器测算运行器的相对速度大小,利用学习阶段计算出海水流速,在水下运行器潜行时进行船位推算导航,用GPS精准的定位信号进行导航误差的校正。此算法精度的高低很大程度上取决于用来进行水下参量测算的传感器和用来方位校准的GPS。文中从各个传感器的误差着手,通过模拟仿真详细分析了电子罗盘、水流传感器和GPS的误差对导航精度的影响,对工程应用具有实际的指导意义。  相似文献   

24~30 GHz GaN HEMT单片集成单刀双掷开关     

曾丁元  朱浩慎  冯文杰  车文荃  薛泉 《南京气象学院学报》2021,13(4):444-449

本文研究了一种基于100 nm氮化镓（GaN）高电子迁移率晶体管（HEMT）工艺设计的24~30 GHz单片集成单刀双掷（SPDT）开关.该开关采用1/4波长微带线并联HEMT开关器件的结构，通过采用两级并联HEMT实现低插入损耗同时获得更好的隔离度.测试结果显示，在24~30 GHz的5G毫米波频段内以及0/-5 V的控制电压下，该开关的插入损耗低于1.5 dB，隔离度优于28 dB，输入功率1 dB压缩点大于27 dBm.测试结果能够很好地验证仿真结果.  相似文献   

Al基牺牲阳极的生物污损——“阳极苞”的解析     

马士德  赵生俊  刘欣  李科  严清冉  李丽娜  韩文  许健平  王启冉  张杰  段继周 《海洋科学》2018,42(10):16-22

本文介绍了铝(Al)基牺牲阳极在青岛中港海鸥浮码头超期服役五年半的阴极保护情况。现场勘查结果发现少部分Al阳极是以"苞"状出现,暂命名为"阳极苞"。其外层为以苔藓虫(Bryozoa/Polyzoa)为主体的生物群落构成的具有一定强度的生物硬壳,内层为白色膏状物,暂命名为"阳极泥"。对生物硬壳进行了生物鉴定,利用扫描电镜(scanning electron microscope,SEM)测试其微观结构,红外光谱(infrared spectroscopy,IR)测定其化学组成,结果表明该生物硬壳由复杂的有机混合物组成,并且具有微米级多孔结构;对"阳极泥"进行了酸碱性测定、能谱分析(energy dispersive spectrometer, EDS)及X射线衍射(X-ray diffraction, XRD)分析,结果表明"阳极泥"主要由铝的水合氧化物和污损生物的代谢产物及机体分解产物组成。在此基础上初步讨论了"阳极苞"的形成过程及其对阴极保护的影响。  相似文献   

Quantitative evaluation and spatial differentiation of eco-environmental livability in Zhejiang Province,China     

《山地科学学报》2020,17(6):1491-1508

The scientific analyses of the spatial patterns of regional eco-environment livability, along with the explorations of the correlations between ecoenvironments and population and economic activity distributions, are of major significance in the guidance of the coordinated development between social economies, natural resources, and environments. In this study, the topography, climate,hydrology, land cover, air quality, and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability. Then,the observed spatial patterns and regional differences in the eco-environmental livability, as well as their relationships with the distributions of population and economic activities in Zhejiang Province, were investigated. The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast, as well as from the mountains to the hills, valleys, and plains areas. During the compartmentalization of the eco-environmental livability, it was observed that the lowest livable area covered the largest population, accounting for approximately 29.64% of the total population in the study area. The higher livable areas covered the widest land areas, accounting for approximately 26.15% of the total area. Moreover, it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province. Furthermore, the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R~2 of the curve-fittings reaching 0.835 and 0.656, respectively. However, it was determined that the coefficient of the exponential function was negative, which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities. It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation. This study introduced two new factors(air quality and natural hazards) into the evaluation framework of eco-environmental livability.As a result, a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally, the correlation between ecoenvironment livability and human activities was discussed in-depth, which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China, and possibly even those of other vast developing countries.  相似文献   

On the giant supercluster binary-like system formed by the Corona Borealis and Abell 2142     

《New Astronomy》2019

The recent hypothesis of a giant supercluster binary-like structure formed by the Corona Borealis and its close companion Abell 2142 (supercluster) belongs to a little known area of investigation as the dynamics of gravitationally interacting galaxy supercluster pairs. From the observational point of view this structure approximates the configuration of a binary-like system in linear orbit interconnected by a huge filamentary structure which, if confirmed, it would be the first case to date observed at z ≥ 0.07. Given the importance to disentangle this issue, a follow-up analysis has been performed on the region constrained by the common envelop of the two superclusters in order to search for new hints to confirm their mutual gravitational interaction. Observational signatures of that interaction have been found mapping the inner peculiar motions where the observed negative peculiar velocities measured within the A2142 (supercluster) region suggest a general matter flow toward the Corona Borealis supercluster. Besides, analyzing the effects on both superclusters due to the mutual impact of the external tidal forces, turns out that their inner dynamics remain unperturbed up to the turnaround radii. Outside, where the binding forces are overlapped by the tidal ones, the outskirts of both superclusters should be unstable and subject to fragmentation. Such a scenario indicates that both superclusters interact with comparable and reciprocal tidal perturbations leaving the whole system in a substantial dynamical equilibrium. The origin of such a dynamical dichotomy would be explained either by a much more massive Corona Borealis supercluster than that estimated in the present work or by a selection effect biasing the small sample of peculiar velocities due to the remoteness of the system worsened by the large uncertainty on their measurements.  相似文献   

交通气象自定义地图服务聚合技术     

焦圣明  郭静  朱毓颖  袁成松  包云轩 《气象科技》2014,42(5):928-933

利用华东各省交通气象信息数据,对共享产品的内容和格式进行了定义和约束,并基于GeoServer和Tomcat平台,运用Java Servlet构建了交通气象专用的地图服务,使得用户可以根据需求自由组合由系统提供的地图资源,从而满足用户需求的地图服务聚合应用。通过对交通气象产品拼图算法、核心GIS处理、XML解析等功能模块的研究与实现,最终完成了基于GIS的交通气象信息共享业务系统。该系统满足了交通气象的业务需求,为交通气象监测、分析、预报服务产品共享提供了技术支持。  相似文献