基于谱图-Radon-二维小波变换方法

线性调频信号已经得到广泛的应用,通过谱图-Radon变换可以有效的检测线性调频信号的参数,但是当信噪比过低时,使用谱图-Radon变换就很难有效检测线性调频信号的参数,为此提出了基于谱图-Radon变换-二维小波变换的线性调频信号检测方法,仿真实验表明该方法能在低信噪比情况下检测出线性调频信号所对应的峰值。     

一种强干扰背景下雷达目标检测算法

将WVD和Hough变换相结合,利用时频聚集性和Hough变换点的累积得到的信号的检测结果,用来检测雷达目标回波信号。然而在强干扰低信噪比下检测能力有限。利用线性调频信号瞬时频率的线性特征,只采用信号WVD时间段的中间部分值进行Hough变换,在时频平面上对WVD的结果进行时间轴上的截取技术,对检测算法作了改进。通过仿真结果表明,改进的检测算法在低信噪比和强干扰环境下能有效地检测出目标信号。     

分数阶傅里叶变换与雷达目标检测

根据雷达目标检测的特点,阐述分数阶傅里叶变换的原理,针对雷达中的线性调频信号,详细描述了分数阶傅里叶变换和LMS自适应滤波相结合的检测步骤。最后对分数阶傅里叶变换算法进行不同步长和不同阶数的收敛性能仿真和分析。     

基于分数阶傅里叶变换的线性调频信号检测算法

针对复杂噪声背景下线性调频信号检测问题,利用分数阶Fourier变换具有解除时频耦合和信号在分数阶Fourier域呈现能量谱的高度聚集的特性,得出一种基于分数阶Fourier变换的信号检测算法,并将算法用于高斯白噪声和色噪声背景中信号检测。仿真结果表明,该算法对高斯、非高斯色噪声中的线性调频信号检测均有良好的检测性能。     

基于STFT与WVD的LPI雷达信号检测

魏格纳分布（WVD）因具有高分辨率、能量集中性和时频边缘特性而成为时频分析的有力工具,然而当处理多分量信号时不可避免的存在交叉项的干扰,因而阻碍了WVD的应用.短时傅里叶变换（STFT）不存在交叉项,但时频分辨力较差.为此本文提出了基于STFT与WVD联合的低截获概率（LPI）雷达信号检测算法,该算法在保证优良时频聚集性和分辨力的同时可以处理多分量信号.仿真实验表明该算法能有效抑制交叉项的干扰,并且在低信噪比条件下可以对LPI雷达信号进行检测.     

检测调频信号的改进算法研究

针对LFM信号,提出了一种改进的LMS算法,通过修正权系数,使之能跟 上信号的调频速率,从而实现低信噪比（-15dB）条件下的信号检测。文中叙述了算法的基本原理及仿真结果,指出了对于LFM信号,修正权系数的LMS算法比LMS算法具有更好的提取弱信号的能力,并且算法运算量小。     

基于WVD和Hough变换二值积累的信号检测方法

WVD-Hough变换是检测多分量线性调频信号的有力工具,但当多分量线性调频信号能量相差较大时,采用WVD-Hough变换进行检测,就会导致强信号对应峰值的平台将弱信号所对应的峰值掩盖掉。虽然可以通过基于＂CLEAN＂思想的算法将信号一一检测出来,但带来的计算量急剧增大。为此在WVD-Hough变换的基础上提出了基于WVD-Hough变换的二值积累方法,该方法可以同时检测出强信号以及被强信号平台掩盖的弱信号,具有很大的实用价值,仿真的结果验证了算法的有效性。     

调频连续波SAR距离-多普勒成像算法研究

调频连续波合成孔径雷达（FMCW SAR）因具有体积小、重量轻、成本低、分辨率高的优点而受到越来越广泛的关注。介绍了调频连续波SAR的去调频信号模型和成像几何模型,重点推导了改进的距离-多普勒算法的流程,通过忽略斜置项和剩余视频相位项（RVP）对成像的影响,从而简化了算法复杂度,并给出了精确成像所需的方位向匹配滤波函数的改进方法,最后通过仿真验证了该算法的正确性和可行性。     

线性调频信号仿真及其特性分析

线性调频(LFM)信号是雷达信号处理系统中应用较为广泛的大时宽带宽积信号。针对线性调频信号进行了时频特性分析,然后运用模糊函数对该信号的性能进行分析,得出该信号具有良好的距离分辨率和速度分辨率,最后对线性调频信号的脉冲压缩过程和结果进行了讨论,并得到了雷达目标回波信号经过脉冲压缩后的仿真结果。     

基于CUDA的雷达线性调频信号脉冲压缩实现

利用图形处理器（GPU）作为雷达仿真平台,采用统一计算设备架构（CUDA）技术,实现雷达线性调频信号脉冲压缩算法,并与CPU算法进行比较。实验结果表明利用CUDA技术实现的脉冲压缩算法取得了比CPU算法明显较高的运算效率。     

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.     

Journal of Marine Science and Application 2014 Sum. Contents

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33rd International Conference on Ocean,Offshore and Arctic Engineering （OMAE2014）

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.     

联合作战计划和执行系统

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。     

The 11th International Conference on Hydrodynamics (ICHD 2014)

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.     

第十二届深水操作会议和展览会(英文)

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.     

Eastbound or westbound ?

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）.     

桥梁防撞设施物理模型试验

物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。     

印尼某电厂码头水工建筑物设计

印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。     

Catalyzing Coastal Management in Kenya and Zanzibar: Building Capacity and Commitment

Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues.