船舶辅助推进系统(APD)简介

本文对船舶辅助推进系统(APD)作了简略的介绍,并对于在APD工作模式下,如何顺利起动大功率电机,以及如何成功接排进行了详尽的说明和分析.     

APD在紫外通信中的应用探讨

在紫外通信系统中通常使用的光电倍增管（PMT）存在着一些不足。雪崩光电二极管（APD）的特点使其具备成为除PMT外另一种可选探测器的潜力。文章介绍了APD的结构和工作原理,分析比较了近期紫外APD的研制成果,提出了应用方案并对其实现进行了探讨。     

关于工程量清单计价模式下招标人风险和控制的研究

工程量清单计价对招标人来说,重要的是如何充分发挥其优势,防范、化解其风险,从而更好地实现控制工程造价的目的。本文阐述了工程量清单计价招标的优势,根据招标流程,针对清单模式下如何编制好招标文件,如何准确评标,如何在招标阶段解决后期结算等问题进行了全面而有重点的论述。本文从招标人的角度出发,针对目前招标工作中普遍存在的几个重点问题进行了风险与控制分析,包括清单招标中如何确定合理低价,怎样应对不平衡报价策略,如何解决低价中标高价结算现象,如何解决结算中合同价款调整,如何应对施工措施费用索赔等,对实际工作有较强的指导作用。     

谈船舶二副工作的特点和重要性

作者根据自己多年的二副工作实践和积累,提出了船舶二副工作的重要性,主要体现在如何执行航行值班和停泊值班,如何根据船长的意图拟订《航次计划》,进行航行航线设计,如何做好航海图书资料的管理,如何对驾驶台设备的进行必要的维护,如何在船尾指挥系解缆作业等。     

船舶电站自动调频调载技术研究

文章介绍了一种基于改进的主导发电机法调频调载技术在船舶电站中的运用,如单机运行时如何稳定发电机的频率,在机组并联运行时如何实现按并联发电机组容量按比例分配有效负荷,重点论述了改进后的方法如何提高系统的动态调节性能。     

关于航标工程审计的有效控制

文章结合航标建设项目工程造价、审计的实践经验,就如何加强航标工程造价管理,如何对建设项目有效控制进行了阐述。     

海运年会 在变革中寻求共赢——记2013年国际海运（中国）年会

全球经济在危机刺激下经历了“伤筋动骨”的结构调整后，进入了大调整、大变革时期。世界海运格局亦正在发生变化，种种变革初露端倪。面对新形势、新变化，仍未挣脱运力过剩困境的国际航运业将如何应对？如何确保增长？如何加快转型？如何驾驭风险？如何从容领跑？     

培养企业精神,加强企业文化建设

本文结合工作实践,着重就如何培育企业精神以及如何加强企业文化建设提出了一些自己的看法。     

由一起对《海员雇佣合同》检查案例引发的思考

文中通过对一起《海员雇佣合同》中发现问题的探讨,详细解读了《劳工公约》中对"船东"的定义,从船东如何招聘合格的船员、船员如何签订劳动合同以及PSCO如何对《海员雇佣合同》开展检查提出了建议,供船东、船员和PSCO参考。     

浅谈企业集团档案管理模式的选择

本文就大型企业集团的特殊性做了总体性描述,从企业集团的特点分析保险企业集团如何进行档案管理模式的选择,围绕保险企业档案管理模式如何确立的问题,对六种不同模式进行分析比较,阐述企业如何选择适合自身的档案管理模式.     

窄带超低频噪声幅度概率分布模式辨识

通过实测数据,研究窄带超低频信道电磁噪声幅度概率分布模式,验证超低频信道噪声幅度服从Middleton的Class B模型。在估计Class B幅度概率分布参数值的基础上,根据概率分布图和Q-Q图结果综合分析做出结论,即采用Class B幅度概率模型,可以很好地描述超低频信道大气噪声数据的幅度统计特性。     

造船项目贷款风险识别与评估方法研究

由于影响项目贷款风险的各要素之间有主次、轻重之分,评价的主体和客体也具有模糊性,因而本文试图运用模糊数学方法研究贷款风险识别评估问题,提出了基于Fuzzy集合论和AHP结合的模糊综合评判法,并引用造船项目贷款案例进行实证分析.     

Optimal reefer slot conversion for container freight transportation

Given a fleet of container ships of varying capacity, a cost-efficient approach for improving fleet utilization and reducing the number of delayed containers is to optimize the sequence of container ships in a given string, a problem which belongs to the large ship-deployment class. A string sequence with ‘uniformly’ distributed ship capacity is more likely to accommodate a random container shipment demand. The number of one’s total ship slots acts as a gauge of the capacity of the container ships. Meanwhile, there are two types of ship slots: dry slots and reefer slots. A dry slot only accommodates a dry container, while a reefer slot can accommodate either a dry or a reefer container. The numbers of dry and reefer slots for ships in a string are different. Therefore, in this study, we propose a model that considers both dry and reefer slots and use it to elucidate the optimal ship-deployment sequence. The objective is to minimize the delay of dry and reefer containers when the demand is uncertain. Furthermore, based on the optimal sequence deduced, the study also investigates the need to convert some dry slots to reefer slots for the container ships.     

移动式近海基地的动力定位控制研究

移动式近海基地是一个大型的、浮动的、自行驱动的、由三至五个模块组成的海洋结构.其中的每个模块均能在风、浪、流作用力下实现长期定位.本文首先讨论了针对移动式近海基地的控制架构.然后针对近海基地中的单独模块设计了一个非线性带前馈的比例微分(PD)控制器,并将其应用到多个模块的运动控制中.文中同时给出了所设计的控制系统的仿真结果.     

Vibration-assisted decommissioning of a slip joint: Application to an offshore wind turbine

An alternative option to the traditional grouted joint for wind turbines is a direct steel-to-steel connection, also known as slip joint. In a recently published work, a proof of concept of a vibration-assisted installation and decommissioning technique of a slip joint was illustrated. Leveraging on the obtained results, the current study shows for the first time a decommissioning campaign carried out using a vibration-assisted technique applied on a prototype hydraulic wind turbine tower located in the North Sea, and connected to the monopile through a slip joint. The key aspect of the dismounting procedure is a priori knowledge of the resonance frequency clusters corresponding to the slip joint’s cross-sectional modes. Therefore, field hammer tests and experimental modal analysis were carried out inside the wind turbine tower. The identified frequencies and mode shapes were then compared with numerical ones estimated by a finite element model of the investigated structure. The comparison showed that a set of frequency clusters can be directly selected from a detailed numerical model. The preparatory work of the slip joint decommissioning was then executed by installing electric shaker devices, based on the dynamic identification results, and hydraulic jacks mounted inside the wind turbine tower. A first decommissioning trial was carried out in May 2019, while the final decommissioning was performed in August 2019. After analysing the measurements of the hydraulic pressures, displacements and excitation frequencies during the decommissioning campaigns, the results showed that it is possible to disconnect the slip joint if, in combination to a vertical static force, one of the identified cross-sectional mode shapes is excited. The vibration-assisted decommissioning proved to be a successful technique to dismount the connection in a controlled and straightforward manner.     

The implications of piracy on marine insurance: some considerations for the shipowner

A prominent feature of modern day piracy is the ransom that is demanded for the safe release of the ship, cargo and crew. The recent upsurge of this type of piracy, in areas of the world that are of strategic importance to the shipping industry, has created many challenges for shipowners, underwriters and the law relating to marine insurance. The aim of this paper is to examine how the marine insurance market is being affected by the threat of modern day piracy, and seeks to identify the options that are available for the recovery of a ransom payment by the shipowner. Moreover, this study aims to identify the legal issues that might prevent a shipowner from recovering a ransom payment under an insurance policy or from the other interests in a common adventure. The study establishes that a reasonably made ransom payment by the shipowner will amount to an extraordinary expense that is taken to minimise or avert a loss. Such an act can generally be recovered under the insurance policy as a sue and labour expense or from other interests in the common adventure as a general average expense. However, illegality, unseaworthiness and exemption clauses in a marine policy are identified as being legal issues that may prevent a shipowner from recovering the ransom payment. Some of these problems may be overcome if clauses are carefully drafted to specifically cater for modern day piracy in a marine insurance policy. Several inconsistencies may also be resolved by transferring the piracy peril to war risks cover. The shipowner’s duty is to respond to the changing circumstances, by ensuring that his vessel is sufficiently equipped and the crew is properly trained to resist a hijacking.     

购建船舶与融资租赁船舶的财务决策研究

自上世纪九十年代以来 ,融资租赁船舶由于其投融资的特殊性在我国航运企业逐渐增多 ,如何进行购建船舶与融资租赁船舶的财务决策成了航运经济界探讨的一个重要问题。提出一种购建船舶与融资租赁船舶的差异现金流量财务决策方法 ,建立了在相同的财务风险条件下 ,购建与融资租赁船舶财务决策过程中租赁租金支付的盈亏平衡点公式 ,对这一盈亏平衡点公式作了进一步的论证。举例表明 ,所建立的融资租赁船舶租金支付的盈亏平衡点确定公式可以使购建船舶与融资租赁船舶的财务决策变得便捷而有效 ,对于其他行业购置与融资租赁某一资产的财务决策同样可以应用。     

Adaptation Pathways in Coastal Case Studies: Lessons Learned and Future Directions

Climate change adaptation presents a difficult challenge for coastal towns around the world, forcing local governments to plan for sea level rise in a contentious decision-making space. The concept of “adaptation pathways,” a diagnostic and analytical tool to assist in adaptive planning and decision-making, is gaining traction as a way of framing and informing climate adaptation. It provides decisionmakers a way to acknowledge the inter-temporal complexities and uncertainties associated with the novel dynamics of climate change and a mechanism to manage these challenges in the local context. In 2012, the Australian Government funded an 18-month program to provide decisionmakers in the coastal zone an opportunity to test the utility of the adaptation pathways concept for coastal climate adaptation. Using a selection of completed projects as case studies, we performed a document analysis to better understand the learnings from the projects. The main themes surrounded: (1) the utility of the adaptation pathway framework in developing options, (2) decision-making rationale and criteria, and (3) stakeholder participation in pathway development. A project participant survey was developed to further understand these themes. Our analysis reveals that “adaptation pathways” was generally framed narrowly and conservatively to emphasize extant economic, administrative and legal considerations over community, participatory, or exploratory ones. Although some case study projects were able to reach a point in the pathway discussion to actively involve stakeholders in their decision-making process, many case studies continued to build technical data as a method for defending policies and actions. These results indicate that coastal adaptation can take-up adaptation pathways as a useful concept for decision-making and planning; however, many councils may still require assistance in stakeholder communication processes in order to develop sociallyacceptable plans that take into account the full range of values affecting local coastal environments.     

Modelling port choice in an uncertain environment

Port choice is an important issue to be investigated to ensure the effective integration of container supply chains and the sustainable development of regional economy. The selection of appropriate ports to facilitate shipping activities and international trade is crucial for many stakeholders, including shipping lines, port administrators, cargo shippers and national governments. The task is essentially a process of multiple criterion decision-making (MCDM) under uncertainty, requiring analysts to derive rational decisions from uncertain and incomplete data related to different quantitative and qualitative determinants. This paper aims at proposing a new conceptual port choice method by explaining the role fuzzy logic in evidential reasoning in a complementary way, in which various forms of raw data (either objective or subjective) collected to evaluate port performance can first be converted into and presented as fuzzy grades defined using linguistics terms with degrees of belief (DoBs) and second be combined using evidential reasoning to produce a port choice preference score. The method is applied to analyse the selection of major Northeast Asian (NEA) container ports from a shipping line’s perspective. The outcome, a port choice preference score, is calculated using evidential reasoning to directly synthesize the true estimation of the port with respect to each criterion and therefore, unlike a relative ranking index, keeps the ‘goodness’ of port evaluation, capable of benchmarking a specific port’s performance and monitoring the increase of its competitiveness in a longitude study with respect to an individual criterion or all the criteria as a whole.