水下自航式海洋观测平台技术发展研究

水下自航式海洋观测平台是一种新型海洋观测平台，主要用于无人、大范围、长时间水下环境监测，包括物理学参数、海洋地质学和地球物理学参数，海洋化学参数、海洋生物学参数及海洋工程方面的现场接近观测。其特点是：成本低，环境适应性强，可冲破人工潜水极限而进入现场进行接近观测，免除了ROV需要水面支援母船的累赘，减少作业经费，体积小，使用方便，便于布放回收；可根据水声信号摇控或预置程序控制，按要求进行相关项目观测；有自主动力，水下运行时间相对较长，有源噪声低，可进行隐弊观测，正是基于以上的优点，近几年颇得海洋环境监测和海军方面的青睐，本文介绍了国际上水下自动观测平台的发展历史和现状，提出了我国开展研究水下自动观测平台的重要性及研究的面容。     

系缆式剖面测量平台运动性能分析

文章简单介绍了系缆式剖面测量平台的结构构成,围绕剖面测量平台升降运动的工作原理,着重对平台的一些固有的基本特性所产生的影响进行了分析,供有关人员参考交流。     

海床基自动监测平台技术的研究应用

介绍了海床基自动监测技术国内外进展，就海床基自动监测平台系统的关键技术进行了论述。海床基自动监测平台系统是携带众多海洋环境观测传感器在海底工作的、自容式综合测量装置。它可布设于河口、港湾或者近海海底，对悬浮泥沙参数、海洋动力参数、温、盐和水质进行长期、同步、自动测量；系统回收后，通过系统软件建立各种海洋动力条件下特别是大风浪条件下悬浮泥沙的运移规律；建立温、盐、水位、流速剖面和通量、水质的时空变化规律。将多个站点的监测数据进行综合处理建立起海洋水体交换生态环境的时空联系，为科学地管理、治理和利用海洋自然环境造福人们提供决策依据。     

Eocene succession on the East Shetland Platform, North Sea

A sand-prone Middle Eocene sequence is recognized in three cored boreholes on the East Shetland Platform. Three lithostratigraphic divisions are recognized: Lower Sand Unit, Main Sand Unit and Upper Claystone Unit. The Lower Sand Unit is of fluvio-deltaic origin, occurring on the southern part of the East Shetland Platform. The Main Sand Unit represents the subsequent transgression of the delta. The unit comprises a set of highstand shelf systems tracts separated by glauconitic bands and reflected by palynological assemblage breaks. The presence of reworked palynofloras in sediments of late Middle Eocene age implies derivation of sediment from the north-west part of the East Shetland Platform. Although it is tempting to ascribe sea level changes to the sediment pattern, a tentative correlation with the Hampshire Basin only highlights the difficulties involved.     

基于USB2.0的海床基自动监测平台数据接口单元的研究

采用EZ-USB FX2技术,设计开发了基于USB2.0的海床基自动监测平台数据接口方式。采用三态双向门电路控制存储器模块总线复用实现数据访问;采用直接内存读写方法完成数据传输;采用参数存储器完成参数设置。实验证明在数据传输、参数设置以及低功耗控制方面取得良好效果,提高了系统工作性能。     

全球Argo实时海洋观测网建设及应用进展

为了使各国政府、部门管理人员和科技工作者了解国际Argo计划的实施进展,以及帮助广大民众认识实施Argo计划的重要性和已经取得的初步成果,国际Argo信息中心、国际Argo科学组和国际Argo资料管理组联合编写了一本科普宣传册,题为“Argo,一个观测实时海洋的剖面浮标网”,经翻译、整理成文,以帮助国内读者深入了解和认识这一新世纪的重大国际观测计划。文章从陈述开展海洋观测的重要性和实施Argo计划的必要性着手,系统介绍了全球Argo实时海洋观测网建设的现状和Argo资料应用研究所取得的初步成果,以及Argo计划的发展前景等。     

Triangular Configuration Tension Leg Platform behaviour under random sea wave loads

This study investigates the dynamic response of a Triangular Configuration Tension Leg Platform (TLP) under random sea wave loads. The random wave has been generated synthetically using the Monte-Carlo simulation with the Peirson–Moskowitz (P–M) spectrum. Diffraction effects and second-order wave forces have not been considered. The evaluation of hydrodynamic forces is carried out using the modified Morison equation with water particle kinematics evaluated using Airy's linear wave theory. Wave forces are taken to be acting in the surge degree-of-freedom. The effect of coupling of various structural degrees-of-freedom (surge, sway, heave, roll, pitch and yaw) on the dynamic response of the TLP under random wave loads is studied. Parametric studies for random waves with different H_s and T_z under the presence of current have also been carried out. For the orientation of the TLP, surge, heave and pitch degrees-of-freedom responses are influenced significantly. The surge power spectral density function (PSDF) indicates that the mean square response is affected by the amplification at the natural frequency of the surge degree-of-freedom and also at the peak frequency of the wave loading. The PSDF of the heave response shows higher peak values near the surge frequency and near the peak frequency of the wave loading. Surge response, therefore, influences heave response to the maximum. Variable submergence seems to be a major source of nonlinearity and significantly enhances the responses in surge, heave and pitch degrees-of-freedom. In the presence of current, the response behaviour of the TLP is altered significantly introducing a non-zero mean response in all degrees-of-freedom.     

Hill Instability Analysis of TLP Tether Subjected to Combined Platform Surge and Heave Motions

This paper presents the Hill instability analysis of Tension keg Platform （TLP） tether in deep sea. The 2-D nonlinear beanl model, which is undergoing coupled axial and transverse vibrations, is applied. The governing equations are reduced to nonlinear Hill equation by use of the Galerkin＇ s method and the modes superposition principle. The Hill instability charted up to large parameters is obtained. An important parameter M is defined and can be expressed as the functions of tether length, the platform surge and heave motion amplitudes. Some example studies are performed for various envirotnnental conditions. The results demonstrate that the nonlinear coupling between the axial and transverse vibrations has a significant effect on the response of structure. It needs to be considered for the accurate dynamic analysis of long TI2 tether subjected to the combined platfolna surge and heave motions.     

Ⅱ类水体光学特性的剖面测量方法

剖面测量方法是国际上推荐测量水体表观光学参数的首选方法，文章在简要介绍剖面测量原理的基础上，根据Ⅱ类水体特点对应用算法进行改进，并给出其应用效果。     

考虑几何非线性的张力腿平台随机响应等效线性化分析

考虑深海柔性张力腿平台的几何非线性特征,建立柔性平台结构非线性随机振动响应分析方法.该方法结合模态分析,把系统隐式的非线性项转化为由模态坐标高次组合表示的显式非线性项,在此基础上引入虚拟激励法,建立结构在随机波浪荷载作用下的等效线性化系统,从而确定结构各非线性随机响应.通过对某一mini-TLP的分析结果和试验实测值的比较,表明该方法具有较好的计算精度和较快的计算速度,能够满足大型结构的非线性随机响应分析要求.通过对不同波高的计算,结果表明张力腿平台在较大波高作用下几何非线性影响显著,忽略这部分的影响,计算结果将会产生很大的误差.     

Automatic collision avoidance of multiple ships based on deep Q-learning

As the number of ships for marine transportation increases with the globalisation of the world economy, waterways are becoming more congested than before. This situation will raise the risk of collision of the ships; hence, an automatic collision avoidance system needs to be developed. In this paper, a novel approach based on deep reinforcement learning (DRL) is proposed for automatic collision avoidance of multiple ships particularly in restricted waters. A training method and algorithms for collision avoidance of ships, incorporating ship manoeuvrability, human experience and navigation rules, are presented in detail. The proposed approach is investigated not only by numerical simulations but also by model experiments using three self-propelled ships. Through the systematic numerical and experimental validation, it is demonstrated the developed approach based on the DRL has great possibility for realising automatic collision avoidance of ships in highly complicated navigational situations.