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1.
针对SAR图像中舰船目标识别的问题,提出了基于核主成分分析(Kernel Principal Component Analysis,KPCA)和核Fisher判别分析(Kernel Fisher Discriminate Analysis,KFDA)相结合的舰船目标识别算法。用核主成分分析的方法对实测的SAR舰船目标数据进行特征降维,再结合核Fisher判别分析法对降维后的样本数据进行多类别分类。将该方法用于对实测的四类舰船目标进行识别,平均识别率可达91.25%。实验结果表明,核主成分分析与核Fisher判别分析相结合的方法可提取目标的有效特征,在较低特征维数情况下获得较高的目标正确识别率。  相似文献   

2.
针对SAR图像中舰船目标识别的问题,提出了基于核主成分分析(Kernel Principal Component Analysis,KPCA)和核Fisher判别分析(Kernel Fisher Discriminate Analysis,KFDA)相结合的舰船目标识别算法.用核主成分分析的方法对实测的SAR舰船目标数据进行特征降维,再结合核Fisher判别分析法对降维后的样本数据进行多类别分类.将该方法用于对实测的四类舰船目标进行识别,平均识别率可达91.25%.实验结果表明,核主成分分析与核Fisher判别分析相结合的方法可提取目标的有效特征,在较低特征维数情况下获得较高的目标正确识别率.  相似文献   

3.
首先利用小波变换对船体表面的灰度图像进行特征提取,得到待检测船体表面的六维小波特征矢量;然后根据最小二乘支持向量机,采用逐级分类的方式进行舰船船体表面质量检测;最后通过实验可知,采用中值滤波进行预处理后的识别率要高于采用均值滤波。  相似文献   

4.
王亚辉 《舰船科学技术》2020,42(16):169-171
传统的数据特征提取方法提取数据特征后不能完全保有数据原有特征,导致方法只能应用于低维度数据特征提取,方法的可行性差。针对以上问题,研究舰船网络数据库中海量数据特征提取方法。设计以神经网络为基本结构的降噪自动编码器,通过编码器对数据库数据降噪。利用基于主成分分析的数据降维算法对数据降维,之后根据数据库中数据的关联性提取数据特征,完成对特征提取方法的研究。设计与传统数据特征提取方法的对比实验,实验结果证明研究的方法能够提取不同维度数据特征,并且应用提取数据特征进行分类时,平均正确率为93.85%,高出传统方法 22.39%,实用性更强。  相似文献   

5.
提出了基于小波包变换和改进奇异值分解的高分辨雷达目标一维距离像特征提取方法。利用该方法对三种目标分类进行仿真实验,结果表明:该特征提取方法,对平移和姿态角变化有较强的稳健性,说明该算法是有效的。  相似文献   

6.
对SAR舰船目标分割方法进行研究,给出一种基于小波变换与K均值聚类相结合的舰船目标分割方法。在该方法中,首先利用双密度双树复小波变换优秀的图像去噪能力,对SAR图像进行降噪处理,以减少相干噪声对分割结果的影响;然后通过改进的K均值聚类方法进行舰船分割。实验结果表明本文方法能有对SAT舰船目标进行有效区分。  相似文献   

7.
随着SAR图像成像技术的不断发展,几何特征被广泛应用在目标识别中,长宽特征因其简单直观、效率高、易于提取等优势,常被作为船只类型的初始判定,针对SAR图像舰船目标长宽特征提取问题,提出一种新的方法。首先通过水平集以及形态学方法获得预处理后的目标图像,利用PCA算法获取SAR图像舰船目标的长轴,结合最小二乘椭圆拟合方法获取舰船目标的短轴,最终得到舰船目标的长宽特征。通过实测SAR图像处理结果表明,该方法能够在背景杂波干扰下,抑制相干斑噪声的影响,提高了长宽提取的精度,是一种有效的舰船目标长宽特征提取方法。  相似文献   

8.
基于高阶谱的舰船噪声特征提取与实验   总被引:2,自引:1,他引:1  
利用高阶谱对舰船辐射噪声进行了分析,着重研究了采用双谱分析的方法提取舰船噪声特征,给出了维谱特征提取的算法,提取了9维的特征向量并利用神经网络进行了训练与识别.实验表明,该方法对舰船辐射噪声信号具有很好的分类效果.  相似文献   

9.
本文利用小波不变矩和支持向量机理论进行舰船目标识别。在识别过程中,首先获取图像,同时将得到的图像转换到极坐标内;然后利用小波矩进行特征提取,在此过程中选择合适的核函数;最后利用支持向量机进行分类。实验结果表明,本文算法具有较高的识别率。  相似文献   

10.
灰度共生矩阵(GLCM)可以描述图像各基元灰度的空间分布和结构特征,而舰船辐射噪声二维谱图中也含有许多目标的固有信息。利用灰度共生矩阵对舰船辐射噪声二维谱图的图像进行纹理研究,求取能量、熵、惯性矩等几个典型特征量,并通过实验室仿真和对实际舰船辐射噪声分析计算,其具有明显的差异,可以作为目标分类和识别的重要特征信息。  相似文献   

11.
正San Francisco,California,June 8-13,2014.OMAE 2014 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to:·meet and present advances in technology and its scientific support;·to exchange ideas and experiences whilst promoting technological progress and its application in industry·to promote international cooperation in ocean,offshore and arctic engineering.In line with the tradition of excellence of previous OMAE conferences,more than 900 technical papers are planned for presentation.Outreach for Engineers Specialty Forum This Specialty Forum is designed for students and professionals who may not be familiar with the Ocean and Offshore industry,as well as those who have just recently specialized in this field.  相似文献   

12.
Errata     
正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.  相似文献   

13.
14.
联合作战计划和执行系统   总被引:2,自引:1,他引:1  
全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划:时间不限的精密预案计划生成作战计划、方案计划或职能计划;时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础,加速应付危机的能力。  相似文献   

15.
Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.  相似文献   

16.
正19–24 October 2014 SingaporeCONFERENCE THEMES The overall aim of the ICHD Conference is to provide a forum for participants from around the world to review,discuss and present the latest developments in the broad discipline of hydrodynamics and fluid mechanics.The first International Conference on Hydrodynamics(ICHD)was initiated in 1994 in Wuxi,China.Since then,9 more ICHD conferences were held subsequently in Hong Kong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,Shanghai and St Petersburg.Evidently the ICHD conference has become an important event among academics,researchers,engineers and operators,working in the fields closely related to the science and technology of hydrodynamics.The 11th ICHD will be held in Singapore in 2014.  相似文献   

17.
正November 4-6,2014Moody Gardens HotelConvention Center/Galveston,TX The Deepwater Operations Conference and Exhibition is celebrating its 12th anniversary this year.This growing event will continue the tradition of excellence in addressing operational challenges involved in developing deepwater resources.We will return to the Moody Gardens Hotel and Convention Center on November 5-7,2014 in Galveston,Texas.  相似文献   

18.
In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama?
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou).  相似文献   

19.
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.  相似文献   

20.
依据码头撞击受损区域调查检测结果,对受损构件提出合理的修复方案,为码头的安全运行提供保障。  相似文献   

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