北极船型破冰来

极地船舶建造市场正成为世界造船业的竞争新"高地"。北极航线破冰而出,极地船舶建造也随之升温。然而,在北极地区航行的船舶面临着许多极地地区特有的风险。由于低温,从甲板机械、应急设备到海水吸入口的许多船舶组件的效能降低。一旦结冰,船体、推进系统和附属设施都将被迫承载额外的负荷。因此,穿越北极航线的船舶与普通远洋船舶有着不小差异。那么,目前极地船舶的设计、建造领域呈现出怎样的格局?未来哪些船型将更适合在北极航     

Mode transitions in vortex-induced vibrations of a flexible pipe near plane boundary

A pipe model with a mass ratio（mass/displaced mass） of 4.30 was tested to investigate the vortex-induced vibrations of submarine pipeline spans near the seabed.The pipe model was designed as a bending stiffness-dominated beam.The gap ratios（gap to diameter ratio） at the pipe ends were 4.0,6.0,and 8.0.The flow velocity was systematically varied in the 0-16.71 nondimensional velocity range based on the first natural frequency.The mode transition between the first and the second mode as the flow velocity increases was investigated.At various transition flow velocities,the research indicates that the peak frequencies with respect to displacement are not identical along the pipe,nor the frequencies associated with the peak of the amplitude spectra for the first four modes as well.The mode transition is associated with a continuous change in the amplitude,but there＇s a jump in frequency,and a gradual process along the pipe length.     

船舶分段建造工程工期、成本、质量综合均衡优化研究

针对当前实际在船舶分段建造工程管理中,人们较少针对工期、成本、质量综合优化的研究,提出通过研究船舶分段建造过程中的工期、成本、质量之间的相互制约关系,得出工期、成本、质量之间的综合均衡优化模型,并利用多目标优化理论和粒子群算法对模型进行求解。该方法能够得到船舶分段建造工程项目管理中的控制目标。     

渤海新建组块海上连调与钻完井联合作业管理提升

为了实现项目产量最大化,渤海新建的A组块工程项目组开展了组块陆地建造完工最大化、组块海上连调生活自持、海上连调期间与钻完井的联合作业管理方案的制定与实施工作.打破了以往新建组块海上连调与钻完井不能并行作业的瓶颈,既实现了工程提前投产的目标,增加了投产井数,又节约了生活支持船,实现了管理和效益的双提升.     

海洋石油平台建造工艺改进的成本分析

文章介绍了某海洋石油平台的建造工艺,以及多个专业方面的建造工艺优化改进措施.从建造工艺改进的角度对海洋石油平台建造投入成本进行数据列举和分析,阐述了工艺改进对成本的重要影响,对类似项目具有较好的借鉴意义.     

施工船舶抛锚作业对海底管道的影响研究

海底管线因碰撞而发生损坏是其面临的主要安全威胁之一,其中锚泊作业引起管线破坏是其中的1个重要方面。依据海底管道风险评估方法,建立锚泊作业时脱锚和锚链断裂情况下抛锚时撞击海底管线概率的数学模型,分别对锚和锚链撞击海底管线的风险影响程度进行研究。利用模拟仿真的方法对建立的数学模型进行了例证研究。     

海底管道可靠性分析

结构完好性评估是任何海底管道的设计、开发和运行的主要部分。海底管道系统的可靠性正是这些结构完好性评估所要保证的。预测管道的可靠性,特别是非线性双层管道（管套管）系统,因涉及的随机变量多而变得越来越复杂。     

A study on dynamic response of cable-seabed interaction

A numerical method is developed to investigate the dynamic response of cable-seabed interaction in this paper. The motion of cable is described by the Lumped Parameter Method, while the seabed, unlike the prevailing simplified model of elastic foundation, is modeled as an irregular continuous rigid surface with rebound and friction existing, and the forces exerted by the seabed consist of normal counterforce and isotropic tangential Coulomb friction resistance. To describe the detailed dynamic response, two coefficients are introduced by analogy with the theory of rigid body collision with friction. The cable-seabed kinematic and dynamic contact conditions are formulated subsequently, and are used to incorporate the seabed effect into the cable dynamics to produce a set of ordinary differential governing equations. In this paper, we employ 4th order Runge-Kutta method to solve these equations. Several simulation cases are presented to illustrate the seabed effect. The results show that friction and impact have a prominent influence on the statics and dynamics of the cable.     

基于神经网络的船体焊接规范自动预测方法研究

针对目前船体焊接规范参数设计的特点,设计了船体焊接规范自动决策的人工神经网络模型．通过实际焊接工艺数据对网络模型进行训练,把以规则显示表达的工艺设计知识转化为隐式网络权值,应用网络推理机快速、准确地预测船体焊接规范参数．实验表明所建神经网络模型具有较好的自学习和预测能力,为船体焊接工艺参数优选提供了一条新途径．     

御风大航海 沃尔沃环球帆船赛全景报道

1海里=1.852公里。这是我要告诉你的第一件事情。为什么1海里比1公里长那么多?耐心看下去,你会得到两个答案的。在此处,先请留意keyword"环球"——沃尔沃环球帆船赛,是一项在9个月内环绕地球航行的比赛。即使对世界上最好的水手来说,也是极限挑战。