环向加肋充液圆柱壳的振动分析

分析中空和充液加肋圆柱壳的自由振动特性，基于Love壳体理论，列出了中空圆柱壳和考虑充液耦合下的振动微分方程，对于两端简支的边界条件，推导出关于中空和充液圆柱壳的频率的特征方程。用代数方程求解公式从而得到方程的解析解；详细讨论了加肋形式、充液对圆柱壳振动特性的影响。     

基于传递矩阵法的纵肋圆柱壳振动特性计算

基于传递矩阵法,结合振动微分方程,提出一种计算纵肋圆柱壳自由振动特性的周向传递矩阵法.该方法基于板壳理论和圆柱壳振动控制方程,推导出圆柱壳周向传递的场传递矩阵和纵肋处的点传递矩阵,结合圆柱壳边界条件,得到频率方程,利用精细时程积分法原理,可保证计算的精度.将计算结果与有限元解进行比较,验证方法的有效性,同时比较传递矩阵...     

轴向压力作用下正交各向异性圆柱壳的稳定性与自由振动特性分析

本文依据Flagge壳体理论，从正交各向异性圆柱壳在轴向压力作用下的自由振动平衡方程出发，推导出在简支边界条件下壳体自由振动的特征方程，分析了正交各向异性圆柱壳在轴向压力作用下的稳定性和自由振动特性，详细讨论了壳体几何参数和材料特性参数以及轴向压力对于自振频率的影响，给出了最低频率随L／R变化的包络线。本文还使用Timoshenko壳体理论进行了比较分析。     

复合材料纵横加筋圆柱壳自由振动分析

使用能量法分析了两端简支复合材料纵横加筋圆柱壳的自由振动特性,从Love's理论出发,分别计算壳体面板和纵横加筋结构的应变能和动能,然后代入Lagrange方程得到频率方程.通过比较,文中的计算方法所得到的结果与文献比较吻合.采用平均法计算的结果比采用离散方法计算的结果偏小.最后还研究了壳体和加筋结构参数以及静水压力的变化对圆柱壳自由振动频率的影响.文中利用平均法来处理加筋结构,简化理论推导并减少了计算.     

流场中环肋圆柱壳的自由振动特性研究

采用能量法分析了流场中环肋圆柱壳的自由振动问题,讨论肋骨布置型式、流场压力对环肋圆柱壳自由振动频率的影响,给出了附加质量和振动波数之间的关系曲线.     

圆柱壳振动分析的波动方法

基于Flügge经典壳体理论和波动方法对圆柱壳的自由振动特性进行了分析,讨论了圆柱壳的频散特性.本文针对3种边界条件,对波动法在频率、振型以及波数等方面的计算精度和经典方法进行了比较.研究表明,波动方法对于薄膜简支边界以及长径比(L/R)较大的情况有良好的精度.     

正交各向异性圆柱壳在轴向压力作用下的静动态特性分析

依据Flügge壳体理论,分析了正交各向异性圆柱壳在轴向压力作用下的稳定和自由振动特性,详细讨论了壳体几何参数和材料特性参数以及轴向压力对于自振频率的影响,给出了最低频率随L/R变化的包络线.还使用Timoshenko壳体理论进行了比较分析.     

环肋圆柱壳自由振动分析的能量法

本文使用Reyaeigh-Ritz法分析了环肋圆柱壳自由振动特性。从Fluegge经典壳体理论出发,考虑肋间壳板的变形以及肋骨在两个轴方向上的弯曲变形,把能量方程成为一个代数特征值问题。本文详细讨论了肋骨的布置型式,数量和刚度的变化对于环肋圆柱壳自由振动频率的影响。本文引入应变能因子讨论了环肋和壳体之间的相互作用。对总体振动和局部振动的问题进行了分析和探讨。     

基于广义多项式混沌法的圆柱壳自由振动不确定性分析

为了实现对舰船结构声振特性的精确预报,开展考虑建造因素的圆柱壳结构自由振动的不确定性分析。在分析影响圆柱壳结构自由振动中的材料不确定性和几何不确定性基础上,应用一般多项式混沌方法建立含建造因素不确定性的圆柱壳结构自由振动的求解模型。最后,基于配点法分析建造因素不确定性对圆柱壳结构自由振动的影响。研究结果可为舰船结构的设计与施工中的建造声学质量控制提供技术支持。     

基于统计能量法研究肋骨对双层圆柱壳声辐射特性的影响

[目的]潜艇的主要结构形式是环肋圆柱壳,目前关于肋骨对圆柱壳声辐射特性影响的研究大多集中在中、低频,但是振动声学问题涉及到更宽的频率范围。[方法]采用统计能量法研究宽频范围内肋骨对圆柱壳声辐射特性的影响。首先,分析圆柱壳增加肋骨后统计能量参数的变化;然后,研究耐压壳、外壳分别增加肋骨、改变肋骨间距、改变肋骨形状对圆柱壳声辐射特性的影响;最后,分析激振力作用在不同位置时,环肋圆柱壳声辐射特性的差异。[结果]得到了肋骨影响下双层圆柱壳在500 Hz～100 kHz范围内的统计能量参数和辐射噪声变化规律。[结论]研究结果对合理选用肋骨降低潜艇的振动与辐射噪声有一定参考作用。     

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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第34届海洋、离岸及极地工程国际会议(英文)

正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 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;     

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。     

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）.     

Recent progress on wave induced loading measurements in warships

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.     

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。     

Impact of regulation on the performances of long-distance transport services: A comparison of the different approaches in Sweden and Norway

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.     

开放式数据挖掘系统模型

目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较，都与国外软件存在着较大的差距。随着数据仓库技术的普及，数据挖掘应用的需求越来越强烈，如何缩短这种差距，研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型，该系统模型从可扩展性、可重用性、易用性等方面得到了加强。