On the existence of an optimal control of ship automatic steering instruments

The existence of linear quadratic optimal control of ship automatic steering instruments is studied. Firstly, the sufficient conditions for the quadratic integrability of the solutions of linear second order time-variant differential equations are developed. Secondly, the optimal control form of the ship automatic steering instrument is obtained by using the dynamic programming method, which guarantees a minimal ship sway range, during long-distance navigation, by using as little energy as possible. Finally, based on the above mentioned sufficient conditions, the conditions for the realization of optimal control are obtained, which provides a foundation for choosing the weighted coefficients for optimal control in engineering.     

小型船用油水分离器

介绍了小型船用油水分离器的工作原理,主要参数计算,影响性能的因素及装船要求。     

SAR图像多尺度积增强的目标检测算法

合成孔径雷达（SAR）成像系统的热噪声和海杂波严重影响SAR图像自动目标检测的性能,去噪和均匀背景杂波是提高SAR图像目标检测性能的重要课题。根据SAR图像噪声功率一般存在于信号小尺度,没有跨尺度特征,而目标信号的边缘具有跨尺度的特点,本文提出了一种多尺度积信号增强和去噪的SAR图像船舰目标检测算法。本算法对SAR图像进行小波变换,应用多尺度积在小波域增强SAR图像船舰信号和均匀背景杂波,再对SAR图像进行目标检测。ERS SAR图像用于验证本文算法。仿真实验结果表明,新算法同传统的双参数CFAR检测算法、基于K-分布背景杂波的检测算法以及基于小波软阈值增强的检测算法相比,在虚警数和品质因数性能指标上均优于后几种检测算法。     

基于AIS的海洋环境目标监测技术研究

介绍了由多种AIS监测平台获取船舶信息的方法,探讨基于AIS的海洋环境目标监测技术。介绍了AIS信息获取和融合技术,提出了同类传感器多源融合与异类传感器多源融合的模型,描述了船只目标信息提取与应用技术。通过收集处理AIS信息,可以大大扩展船舶的监视范围,对于提高船舶动态的监控能力和海上安全的保障能力具有很重要的意义。     

机载LiDAR点云的Delaunay三角网快速生成算法

为了提高机载激光点云的Delaunay三角网生成效率及稳定性,基于分块算法的思想,改进了点云数据的分块方式,利用点云的凸包及重心点进行数据分块,并结合子块中激光点个数阈值进行三角形子块的细分,从而避免了传统子块合并过程中复杂的相邻三角形搜索及优化处理,仅需简单的一步优化即可完成相邻子块的合并,大大提高了算法的效率。经实验证明,该算法简单、高效且稳定性好,尤其对于大数据量的机载LiDAR点云Delaunay三角网生成具有明显的优势。     

现代测量船的装船建造技术

论证了测量船建造工程各个技术环节对测量系统工作效益的重要作用,分析了测量船总体设计和测量系统装船工程的实施效果对测量系统技术性能的巨大影响。通过对比近期测量船建造工程中正反两方面的经验,提出了能够适应当代海洋测量飞速发展要求的测量船建造保障技术措施。     

天宫一号高光谱数据的船只检测实验

针对检测目标进行基于引力场的船只目标增强,计算船只目标的纹理、光谱等指标,基于支持向量机(SVM)方法,利用天宫一号高光谱数据,得到空间探测信息与地面实际目标之间存在精确的相互关系,进行船只检测实验研究.结果表明:天宫一号高光谱数据能够有效的从海水背景中提取船只信息,但船只类型仍难以有效识别.图像的自动分割对于船只的检测非常重要.传感器的多光谱与高分辨率相结合是今后研制的一个主要方向.     

海洋石油支持船节油途径浅探

海洋石油支持船的船舶特性及其作业任务的特殊性,决定了不能照搬照抄航运企业的经验,必须探索出一条自己的节能减排路径.在分析各种影响船舶油耗的因素的基础上,筛选出海洋石油支持船节油空间较大以及可控的影响因素,提出节能减排的实施思路.     

波浪作用下带月池结构船体运动数值预报

流体在月池内发生共振时,有可能给船舶带来多种危险。建立基于N-S方程和VOF法的三维数值波浪水池,通过实现船体与波浪的耦合运动,对月池内流体发生活塞运动共振情况下的船体运动做出了数值预报,研究了船体运动和月池内流体运动的相互影响。通过与无月池结构船体运动对比,得到了共振情况下月池内流体活塞运动会增大船体垂荡运动的结论;通过与船体静止情况下月池内流体运动的对比,得到了船体运动会增大月池内流体活塞运动的结论。另外还研究了月池内的流场变化,以研究月池振荡的机理。     

Protracted Environmental Issues on a Proposed Titanium Minerals Development in Kenya's South Coast

This study takes cognizance of the fact that the TIOMIN (TIOMIN Resources Inc. of Canada) project has resulted in controversy over its handling of environmental issues and especially the Environmental Impact Assessment (EIA). The authors address many of the protracted issues that have slowed the development of the mining project in Kwale. The main emphasis is on the impacts of the mining and mineral separation processes on the environment, including the governing legislation, the role of consultation and public participation, and socioeconomic issues. In their public documents TIOMIN has specified neither the type of minerals it wants to extract from the area nor their chemical composition. It is well known, however that the titanium minerals and zircon targeted have impurities of iron, thorium and uranium. In the absence of an Environmental Management Plan, the effects of stockpiling radioactive wastes and other impurities that could possibly lead to environmental degradation in both the terrestrial and marine environments have not been publically addressed. The measures proposed to mitigate ecological damage as a result of the establishment of a minerals processing plant in the area seem inadequate. Pollution resulting from accidental spillage or breakage could have significant impact on marine life and residents living near the mining site. Other issues that have not been addressed satisfactorily pertain to the use of surface and underground water. The area already faces a huge water deficit and the calculations presented on aquifer recharge and stream flow rates do not indicate the large quantities of water that would be required in the mineral processing plant. The project, if approved in its present state, risks violation of international conventions. Furthermore, it could cause a conflict between Kenya and Tanzania in the event of an oil spill at the proposed ship loading facility at Shimoni. The proposed mining area includes the district's most fertile land, is home to many fisherfolk and is a major tourist destination. An analysis of the effects of this project on other available opportunities must be thoroughly understood to ascertain the economic and environmental benefits and costs of the mining venture. The proposed compensation rate of $1,000 per acre, for resettlement for example, appears to be grossly inadequate. Compensation should take into account family size and structure family assets and the cost of relocation.