海洋固定平台过渡段安装技术分析

过渡段作为连接海洋桩基平台上部结构与导管架的关键构件，起着非常重要的作用。但在进行海洋石油开发相当长的一段时间内，其安装过程中钢桩跨距的测量都是采用在钢桩上盘尺的方法，而这种方法往往会导致较大的误差，甚至有可能导致上部组块难以安装。随着技术的进步，一种通过AUTOCAD与先进的测量仪器相结合的测量方法已成功地应用于多个项目，这种科学、准确、高效的方法把过渡段安装的技术提高到了一个崭新的高度，为平台上部结构的成功安装提供了强有力的保证，以位于南海北部湾海域的涠洲WZ12-IB平台的工程实践为例来介绍了过渡段安装过程中采用的新方法。     

舰用电站柴油机过渡工况的性能研究

采用自行设计的过渡工况控制及测量系统，对舰用电站柴油机进行加载过渡工况下柴油机的空燃比、消光烟度及示功图参数的测试；试验结果表明，随负荷增加率的上升，空燃比减小，燃烧恶化，燃烧始点后移，预混燃烧比明显下降，上述原因导致了在加载过渡工况下，随负荷增加率的升高，柴油机的性能恶化。油耗增加，燃烧噪声变大，排气烟度上升。     

坞墩橡胶支座在平台浮托下水中的应用

在海工行业,由于湿拖过程中来自海况、拖船及平台自身的不稳定因素,平台通常采用半潜船干拖至作业位下潜浮托方式就位.因此,用于平台下水所用的垫木墩子扮演着重要角色. 传统的垫木墩子大部分是由水泥垫块加垫木或钢结构加垫木的结构组成,此种垫木墩子刚性有余而弹性不足,仅起到半潜船与搭载平台之间的过渡作用.     

一种面向智能校园网的IPv6过渡技术

分析了双栈协议、隧道技术和NAT—PT技术这3种常用的过渡机制，并通过一个IPv6实验床的建设，利用IPv6双栈协议和隧道技术过渡机制，有效地实现了校园网从IPv4向IPv6的平滑过渡。与已有的技术相比，该方法实现了IPv4和IPv6的共存及协同运行。     

船舶轴带发电机系统建模与计算机仿真研究

以2700TEU的某集装箱船为母型，根据远洋船舶轴带发电机系统的工作原理和结构组成，建立系统各主要组成环节的数学模型，并利用MINIS通用仿真支撑平台实现了整个船舶轴带发电机系统的仿真。所建立的数学模型可以仿真轴带发电机系统的正常工作过程和过渡过程，达到了较高的仿真精度。     

钢-铝合金结构过渡接头焊接工艺参数的计算确定

以结构过渡接头界面温度低于临界温度为准则，用焊接热过程理论确定临界焊接热输入，为结构过渡接头与上层建筑及主船体焊接工艺参数的计算确定提供依据；计算确定的焊接工艺参数，保证结构过渡接头焊后具有爆炸复合的原有性能。     

带式输送机过渡段距离设计分析

本文通过对输送带处于过渡段应力应变状态的分析，并对公式及图表进行对比和分析，以加深对过渡段距离优化确定的理会和在实际设计中的灵活运用。     

海堤不同地基加固衔接位置的处理方法

针对爆破挤淤与塑料排水板衔接堤段条件复杂的特点，对其衔接位置选址及处理方法进行研究。通过分析堤基范围内地质条件特征，结合海堤建设时序、整体稳定性、差异沉降及工程投资等因素，选择软土层薄、砂层厚及轴线拐角的堤段作为衔接位置。基于爆破振动影响，减少衔接位置的爆破挤淤进尺，预留排水板安全距离，先进行爆破挤淤再施工排水板。采用简化肖普法对衔接段海堤进行稳定复核，增加反压平台，与相邻海堤平顺过渡，并经现场验证。结果表明，选择合理的衔接位置可有效减少工程投资，确保海堤安全可靠、平面平顺衔接。     

柴油机曲轴臂距差与曲轴疲劳强度的关系

研究了柴油机曲轴的臂距差与曲柄销过渡圆角处附加弯曲应力的关系，论述了曲轴臂距差对曲轴疲劳强度的影响，并推导出由于轴系失中引起的曲柄销过渡圆角处的附加弯曲应力计算经验公式。通过实例计算，提出二冲程低速柴油机附加弯曲应力集中系数经验值，同时验证经验公式的可靠性。本文研究成果不仅对曲轴的设计，而且对船舶轴系设计、审图及故障分析均有指导作用。     

非轴对称球锥过渡环有限元分析及优化设计

利用大型通用软件Ansys,基于参数优化设计的思想,以过渡环及相邻球壳的最小重量为目标,同时考虑强度及稳定性的要求,对过渡环进行了参数优化,并分析了过渡环在最小重量情况下的应力分布规律,提出了参数调整的方法。     

Changing policies in Eastern Europe and their impact on the maritime field: experiences from Eastern Germany

The political changes that occured in Eastern Europe from the late 1980s coincided in the fromer German Democratic Republic (GDR) with the reunification of Germany. The economic result was the existence of a split economy in Germany. Within the maritime field the problem had to be solved by a change over of the former GDR's maritime industry from the centrally-planned command type economy as its failure was evident. Three economic factors were identified as the main causes for the failure which made, together with some other negatives, the collapse inevitable. The transition of the East German maritime industry started immediately after reunification. In the maritime field, two different forms of economic transition have been applied. Using the examples of the main shipping company and the seaports the economic transition process has been analyzed and some basic conclusions regarding the substance and methods of economic transition have been drawn.     

Fatigue life estimation of explosive cladded transition joints with the use of the spectral method for the case of a random sea state

The problem with fatigue lifetime estimation of explosive cladded transition joints under random loading conditions has been described. The paper presents the fatigue test results performed for the random state of tension-compression under a generated spectrum according to the Pierson-Moskowitz model. The obtained spectrum has a non-Gaussian characteristic. The tested material consists out of a transition joint clad with four layers of aluminium alloy A5083, A1050, Titanium Grade 1 and steel Grade D. The material has been tested for the existence of residual stresses after the welding process with the hole drilling method. The welding process has been also simulated with ANSYS and the residual stresses have been generated for the Goldak volumetric distribution. The obtained values of residual stresses comprise to the values of real tests performed for the hole drilling method. The information about the residual stress values have been taken into account in the process of fatigue lifetime estimation in the form of non-zero mean stresses compensation inside the clad. The fatigue life has been calculated with the use of the frequency domain method. The Goodman mean stress compensation model has been used in the process of residual stress compensation. The non-gaussianity has been compensated with the use of the Bracessi formula. The obtained fatigue life assessment results have been compared with stand test results. The calculated results are within the scatter area of 3, but individual scatter values have been calculated for calculated series.     

Nations and regions in transition

The workshop included presentations of nine papers covering very different types of situations and transitions. Some papers were region specific (Russia, Middle East, Asia, Europe, and two from Latin America) and others were of general applicability. The discussion highlights that virtually all cities and regions will go through one type of transition or another, sooner or later, and that the study of such transitions provides a very rich learning environment. The most important conclusion has been that in many cases the stability of supply and accessibility to public transport by all population segments is more important than competition and ownership.     

客滚桥桥体长度确定及过渡板改造设计

客滚桥是连接客滚船与岸壁的重要设施,与广大旅客生命及财产息息相关。本着经济适用、简单安全可靠、维修方便等原则,确定客滚桥桥体长度和过渡板改造设计。     

Factors Controlling the Development of the Aquaculture Industry in New Zealand: Legislative Reform and Social Carrying Capacity

The New Zealand aquaculture sector, consisting of mainly mussel, oyster, and salmon farmers, has been expanding over the last two decades. The increasing demand for water space for marine farming has prompted a process of community consultation and legislative reform resulting in the Aquaculture Reform Act 2004. Despite efforts to develop more effective legislation and improve the application process, marine farmers have often been relatively unsuccessful at gaining the water space that they desire for the expansion of the industry. However, social factors such as landscape and amenity values, recreational and navigational use, and alienation of public space are the most frequently cited reasons for the refusal of marine farm consent applications. An analysis of resource consent decision records from the past decade demonstrates this conclusion that the main factor limiting the further expansion of the aquaculture industry in New Zealand is the social carrying capacity, in the context of a period of legislative transition.     

Low-aspect ratio appendages for wind-assisted ships

Journal of Marine Science and Technology - Wind propulsion for commercial ships has been identified as a key component in the energy transition for the maritime industry. The sailing hybrid ship...     

自由衰减模型试验的横摇阻尼评估方法研究(英文)

The methodology to obtain the non-linear roll damping from decay tests is very old. It has been proposed by Froude in the 19th century and used from then on. Behind it there is a quadratic model [θ│θ│] for the damping and a subsequent equivalent linearization. Probably all model basin in the world follows this approach to assess the damping from a decay test. This is well documented and so is the methods to get the p1-p2 coefficients. This is very general in the sense that in principle,it could be applied t...     

数控编程中尖角过渡问题的探讨

简要讨论了采用直线过渡方式和圆弧过渡方式进行工件轮廓尖角过渡处理的基本原理和编程方法,深入分析了两种尖角过渡形式对工件转角处的加工质量、加工效率和刀具耐用度等的影响和在数控编程中的应用范围。     

船舶电站交流主发电机瞬态电压调整率分析

从电机电磁过渡过程的角度分析了影响发电机瞬态电压变化率的主要因素,并介绍了一种计算交流发电机瞬态电压调整率的工程算法,且得到了某发电机的试验验证,具有一定的工程应用意义.     

发电机、主/配电盘故障下船舶动力装置性能分析（英文）

Power generation is one of the most essential functions of any plant for continuous functioning without any interruption. A marine power plant(MPP) is the same section. In the present paper, the authors have tried to find the various reliability characteristics of an MPP. A marine power plant which is a composition of two generators and in which one of them is located at the stern and another at the bow, both associated to the main switchboard(MSB). The distribution switchboards(DSB) receive power from the MSB through cables and their respective junctions. Given that arrangement, a working based transition state diagram has been generated. With the help of the Markov process, a number of intro-differential equations are formed and solved by Laplace transform. Various reliability characteristics are calculated and discussed with the help of graphs.