浅谈沿海船舶防污染管理的现状与对策

船舶造成环境污染的事故屡见不鲜,文中通过分析海事管理现状及沿海船舶防污染存在的主要问题,提出相对应的管理对策,使海事管理机构明确自身在涉及船舶防污染操作、管理、监督等方面的责任,发挥作用最大限度地减少船舶对海洋环境的污染。     

《海上交通安全法》中海事行政处罚对象辨析

通过对《海上交通安全法》和其他相关海事行政法规所规定的处罚对象中船舶所有人、经营人和管理人定义与责任的梳理辨析,进一步明确《海上交通安全法》规定中不同情况下的责任人,以期为海事管理机构和其他有关部门在执行针对船舶安全、防污染等方面的行政处罚时的对象选择提供建议及对策。     

船舶定线制下碰撞事故的责任认定

船舶碰撞事故的责任认定，是两艘及以上船舶之间发生碰撞造成损害后，海事管理机构依法对碰撞事故调查取证，并对当事人的责任进行认定的过程。[编者按]     

谈FPSO海事监管——"南海奋进"号FPSO海事监管现状之思考

随着海洋石油开发步伐的加快,FPSO的数量也随着增长。对FPSO的海事监管进行深入的探讨,明确海事管理机构职责,有利于海事管理机构开展FPSO的监管工作。文章通过分析“南海奋进”号FPSO海事监管现状,研究现有的有关法律、法规和规章,结合FPSO的特点,对海事管理机构在FPSO海事监管中的职责提出了自己的观点。     

船舶超载运输的界定及监管对策

从船舶超载的定义出发,分别引用国际公约和国内规范界定船舶超载的定义。在此基础上,分析船舶超载的危害以及海事管理机构对此类船舶的监管难点和监管现状,提出海事管理机构应加快形成现代海事监管方式、依托信息化促使海事监管手段多样化、建立船舶超载运输责任倒逼机制等对策。从源头上治理船舶超载,联合各单位打造责任链、编制安全网,形成多方联动、一致行动,从而树立海事执法的威严,为水上安全通航和人命财产安全保驾护航。     

由海事管理机构指令开展的清污行动的法律性质分析及建议

海事管理机构指令清污单位开展清污行动的性质,关系到海事管理机构能否正常履行职责和维护清污单位的正当权益。通过案例分析海事管理机构、清污单位和污染责任方三方关系,得出结论:海事管理机构指令开展清污行为是行政代履行行为,追偿费用适格的诉讼主体是海事管理机构而非清污单位。对海事管理机构对清污单位的监管和履行程序提出建议,以期更好地完成清污工作,维护各方利益。     

海事安全监管责任风险与对策

在海事安全监管过程中,各级海事管理机构都面临着责任风险。如何建立与之相适应的海事风险管理机制,完善海事管理体系和手段,有效防范和规避海事监管责任风险,积极降低海事监管责任风险的危害后果,为海事管理机构和执法人员提供必要保障,是当前亟需认真研究和解决的问题。     

海事管理机构推进企业主体责任落实工作研究

笔者从我国现行安全生产相关法律法规及安全生产监督管理体制两方面,分析海事管理机构对航运公司监督管理职责的主要内容,对比海事管理机构与交通运输主管部门在航运公司安全生产主体责任落实方面的不同职责,提出海事管理机构推进航运公司安全生产主体责任落实的主要思路和措施。     

《海上交通事故调查报告》可否公开

《中华人民共和国海上交通事故调查处理条例》（下称《海事调查条例》是海上交通事故调查的法律依据。《调查条例》第十五条规定：“港务监督应当根据对海上交通事故的调查,做出《海上交通事故调查报告书》,查明事故发生的原因,判明当事人的责任;”但对于《海上交通事故调查报告书》是否对社会公开,海事管理机构内部有不同意见。笔者从法理并横向比较道路交通事故调查、民用航空器飞行事故调查的相关规定,提出自己的见解。     

海事违章处罚加处罚款收缴难问题与对策探讨

行政处罚加处罚款制度的设立,旨在通过让不履行行政处罚决定的当事人承担更加不利的后果,从而督促当事人自觉履行行政处罚决定。但在海事管理机构执法实践中存在诸多难题。为进一步规范执行程序,有效解决其收缴难的问题,文中主要对海事管理机构在加处罚款执行过程中存在的若干问题进行简要剖析,并提出相关建议,以期达到有力打击海上违法行为,实现海事服务职能的最终目的。     

大型船舶系泊系统的动力响应研究

通过对大型船舶所受载荷情况的分析,采用静力分析方法结合国内、外有关的经典计算公式,对船舶所受的风载荷、流载荷和缆绳受力情况进行研究。结合具体工程案例,计算船舶的受力情况,以及在风、流作用下系泊时缆绳受力是否在允许的安全范围内,对该船的系泊安全和码头安全做出评价。     

破碎波对随机波统计特性影响的实验研究(英文)

The influence of wave breaking on wave statistics for finite-depth random wave trains is investigated experimentally. This paper is to investigate the influence of wave breaking and water depth on the wave statistics for random waves on water of finite depth. Greater attention is paid to changes in wave statistics due to wave breaking in random wave trains. The results show skewness of surface elevations is independent of wave breaking and kurtosis is suppressed by wave breaking. Finally, the exceedance probabilities for wave heights are also investigated.     

Wave-in-deck loading on fixed steel jacket decks

For quite some years, wave-in-deck loading has been an issue of concern for engineers dealing with the performance of offshore structures. The topic is particularly relevant for reassessment of existing structures located in subsiding areas. One agrees that wave-in-deck loading is of dynamic nature, and that structural analyses should reflect this. There is, however, no general consensus on the size of the load and the shape of the load time history to be used for such analyses.In this paper focus has been on finding realistic load time histories for wave-in-deck loading on jacket platforms in the North Sea. A (normalised) time history shape and a simple expression to calculate a reference load (maximum load) to quantify the time history is presented.The presented ‘recipe’ for time histories is based on experimental data and is supported by results reported in the literature, comprising relevant computer simulations and model experiments of wave-in-deck loads on fixed offshore structures.The recommended load time history is intended for analyses where detailed information on the deck load for a given structure is unavailable, and where a simplified ‘rough-but-reasonable’ estimate can be accepted.     

港口散货堆场带式输送机减电机运行节能技术研究

港口煤炭、矿石等散货堆场用带式输送机经常在轻载下运行，输送机所需要的传动功率较低，出现严重的“大马拉小车”现象，导致其电动机能耗较高，系统功率因数较低。在分析研究堆场带式输送机减电机节能运行的关键技术的基础上，编制了输送机减电机运行计算软件，提出了堆场带式输送机减电机运行的合理建议。     

Accelerated second-order hydrodynamic load calculation on semi-submersible floaters

A rapid method for calculation of second-order hydrodynamic wave loads on semi-submersible platforms is developed and validated against radiation–diffraction theory. The method is based on slender-body theory and builds on modal truncation of the quadratic transfer function (QTF). The semi-submersible floater is split into individual members and the existing theory for vertical cylindrical columns is extended to include the heave force. Further expressions for the surge, heave and pitch load on the horizontal pontoons are derived and implemented. The accuracy of the method is assessed by comparison to radiation–diffraction results using the Pinkster approximation. We find that the slender-body approximation for the column surge force is most accurate for small values of the diameter-to-draft ratio. For the three sea states considered, this error is below 10% for diameter-to-draft ratios less than 0.2.Error analysis is provided for the column heave and pitch and the pontoon loads. For all members, application of 128 modes in the QTF approximation is found sufficient to accurately represent the full slender-body QTF solution.Next, the first- and second-order loads on the full floater under different sea state conditions are compared to radiation–diffraction theory. With 128 modes, the second-order loads are obtained 2500 times faster than with conventional approaches with error levels of 22% for surge, 10% for pitch and zero error for heave. The surge error is discussed and linked to the small draft of the columns. The numerical efficiency of the method allows the consideration of second-order loads in the first stages of the design and optimisation of semi-submersible floaters.     

The Impacts of Recreational Four-Wheel Driving on the Abundance of the Ghost Crab (Ocypode cordimanus) on a Subtropical Sandy Beach in SE Queensland

There is increasing concern regarding the impacts of recreational four-wheel driving (4WDing) on sandy beach environments. The ghost crab Ocypode cordimanus is a widely distributed Australian species that utilizes beaches and dunes for constructing burrows and for foraging. Comparisons of ghost crab abundances (using burrow counts) in areas “open” and “closed” to recreational 4WDing were conducted on exposed sandy beaches on North Stradbroke Island, off the coast of southeast Queensland. Beaches where recreational 4WD activity is present had significantly lower ghost crab abundances than beaches where it is absent. The most plausible reason for this difference in abundance is that ghost crabs are highly vulnerable to being crushed by beach traffic when feeding on the beach at night. To mitigate the impacts of recreational 4WDing on ghost crab population management intervention is needed. Possible changes to the management of recreational 4WD activity include the setting aside of areas free of recreational 4WD activity for the conservation of biodiversity, or a prohibition on driving on the beaches between dusk and dawn. There is also a need for a consistent and transparent approach in Queensland for quantifying and monitoring 4WD activity in sandy beach environments.     

自升式平台齿轮齿条失效判别方法

齿轮齿条的强度是关系整个平台安全性能的一个重要因素,对其进行强度校核非常必要,而对齿轮齿条进行强度分析的关键问题就是确定施加在齿轮齿条上的载荷。通过建立平台整体有限元模型,分析平台爬升齿轮齿条所受载荷,将上述载荷施加在有缺陷的齿轮齿条模型上,计算出齿轮齿条的极限磨蚀或腐蚀量,并将此极限磨蚀或腐蚀量作为判断目标平台齿轮齿条失效的标准。     

基于光电复合缆的水声信号采集发射传输系统

众所周知水下电磁环境复杂,在水下采用电缆传输电信号非常容易受到海洋电磁环境干扰,并且随着距离的增加,电信号受到干扰和衰减也就越大.因此水下中长距离的信号传输采用光电复合缆传输是一个比较好的选择,光纤用来传递水声信号,电缆用来传输电力.因此本文设计了一种基于光电复合缆的水声信号采集发射传输系统,能够很好地解决上述问题.本设计将要采集和发射的水声模拟信号在采集发射端和主机端转换成光信号,端到端之间的传输采用光信号,而采集发射端的供电则由光电复合缆的电缆提供.     

Effects of tension gap on the holding capacity of suction anchors

Suction anchors are popular anchoring solutions for station-keeping of offshore floating facilities. For the in-place holding capacity design of these anchors, there is a debate in practice regarding the possibility of developing a tension gap on the rear side of the anchor and how to account for it in design. This study is carried out to shed further light on this debate. Analytical and finite element analyses are reported in this study which investigate: i) the optimal padeye depths and the influencing factors, for both free gapping and no gapping interface conditions; ii) the effect of tension gap on the anchor's holding capacity when the padeye is placed at optimal depths; iii) the effect of tension gap on the anchor's holding capacity when the padeye is placed at non-optimal depths. Strategy to account for tension gap in practical design is provided.     

Foundation damping for monopile supported offshore wind turbines: A review

Today, an important challenge for offshore wind energy is to design efficient and reliable offshore wind turbines (OWTs). The overall damping of OWTs plays an important role in the design process as it limits the amplitude of the OWT dynamic response at frequencies near resonance. Therefore, an accurate estimation of OWTs damping is necessary for the efficient design of these systems. The foundation damping is one of the main sources overall turbine damping and is the least well understood. This paper presents a critical review of recently published studies on foundation damping for OWTs on monopiles and explains how soil damping contributes to the total damping of OWTs. It also reviews the main methods that have been used for the estimation of foundation damping in numerical and experimental studies. In addition, the importance of damping to the OWTs fatigue life is discussed. Finally, a discussion is provided on the challenges to be overcome and recommendations for the accurate estimation of foundation damping.