单相岸电与船内三相电源的协调设计

在船舶电气系统设计中，业主有时要求设一个220VAC的单相岸电，以作为停泊时的照明电源。这就需要在船内三相220VAC电源线路上作相应的调整，使得在接单相岸电时，该线路变为单相电源供电的线路，且又不影响在三相电源供电时负载平衡的线路结构。     

船舶照明系统中的小设计

在船舶照明系统设计中，业主有时候要求设置1个交流220V的单相岸电，作为停泊时的照明电源。这就需要在船内3相220V电源线路上作相应调整，使得在接单相岸电时，船内3相电源供电的线路变成为单相电源供电的线路，而又不影响在3相电源供电时负载要求平衡的线路结构。     

基于ETAP的海洋平台末端设备短路预估的研究

发生短路过电流电气故障时，为了能对电气末端设备进行保护，需要预估电气末端设备汇流排的短路电流。应用ETAP(电力电气分析、电能管理综合分析软件系统)通过不同电缆长度预估出上游短路电流贡献值，通过电机短路电流快速计算法预估出下游短路电流贡献值，汇总获得电气末端设备汇流排的短路电流。预估出的短路电流为电气末端设备选用合适的保护电器和汇流排等提供了依据。本预估方法适用于船舶及海洋平台等孤岛式电网具有一定的通用性及经济性。     

500kV同杆双回输电线路潜供电流与恢复电压的研究

随着电力建设的发展,电网间联络的增强,工频过电压降低,使得100km左右的线路,不需用并联电抗器来降低工频过电压;还有一些线路采用了静态补偿装置,于是这些线路的潜供电流得不到有效地限制,单相自动重合闸成功率降低,这给系统的安全运行带来许多问题。本文主要对以上问题进行了分析和研究。     

武汉天网公司推出高压单相细水雾灭火系统

武汉天网消防设备有限公司是一家以华中科技大学为技术依托，集高科技研发生产、工程施工和技术服务于一体的综合性环保企业。公司目前的主营产品是高压单相细水雾灭火系统及相关技术的研发、生产、销售与咨询。在今年的武汉机博会船舶展上，他们带着实物展出了船用高压单相细水雾灭火系统，该系统采用高压单相细水雾灭火技术，具有灭火机理先进、灭火效率高、安全、无危害、对环境无污染以及对设备无破坏性等突出的优点已成为国际上消防行业的最新发展方向。     

新型动态无功补偿装置研究及应用

1 引言 在由电厂发电机、变压器、港口用电设备及供用电线路组成的系统中,变压器、门机等港口用电设备作为感性用电负荷,在对外输出有功功率的同时,也消耗大量无功功率,如果不采取有效措施,无功功率将由发电机供给,而输配电线路和变压器将造成电压损失和电能损失.对于装机容量较大、用电设备分散的港口供用电网的无功补偿,采取大型用电设备就地补偿和变电所集中补偿相结合的组合无功补偿方式,是提高功率因数、降低电能损失的有效途径.     

一种岸电单相运行保护线路

船舶靠岸后接用三相三线380伏岸电。为防止岸电电网发生单相运行而导致船舶电网单相运行,下面介绍一种简单,可靠的保护线路。图1是它的原理线路图。当岸电接入后,接成星形的三只交流继电器JZ动作,闭合常开触点,继之,时间继电器SJ动作,手动合闸     

基于PI-RP复合控制策略的船用单相APF设计与仿真

为抑制和滤除舰船电网上非线性设备引入的谐波干扰,针对舰船设备特性设计单相有源电力滤波器(Active Power Filter,APF).分析论证了单相APF的技术原理、主电路构成及拓扑结构,比较几种常用的谐波检测算法和控制策略.针对PI(比例积分)控制和RP(重复)控制各自优点及不足,设计采用二者并联运行的复合控制策略以有效提高稳态精度和动态性能.利用MATLAB/Simulink软件建立系统仿真模型,仿真实验结果表明单相APF滤波效果良好,也验证了复合控制策略的有效性.     

货船空调噪声的来源及控制

货船空调是为货船的居住区域提供新鲜和温度适宜空气的。如果空调送风产生较大噪声,会直接影响船员的日常工作和生活,所以对空调噪声的控制,在现代船舶中十分重要。货船空调噪声主要来源有背景噪声、空调自身的设备噪声、风管传播噪声和室内末端设备噪声。通过对货船空调噪声形成原因的分析,探讨了在设计和建造中,通过合理有效的手段,控制货船空调噪声的方法。     

单相感应子发电机电压控制研究

单相感应子发电机广泛地应用于舰船的中频电源系统中，其输出电压受电网电压和负载影响较大。通过分析感应子发电机的工作原理，采用PI调节和脉宽调整技术相结合的方法来调整其励磁电流，从而使其输出电压稳定。试验验证了这一技术的可行性。     

开敞式码头系泊缆绳的优化研究

运用OPTIMOOR系泊软件,以减小环境荷载作用下船舶运动量及均衡缆绳张力分布为优化目标,结合江苏某港10万吨级石化码头,通过对比不同的缆绳材质、调整缆绳长度、调节缆绳预张力来优化开敞式码头系泊缆绳的布置。计算结果表明:增加缆绳长度可降低缆绳张力,设置尾缆能显著降低系泊钢缆的动力负荷,减少船舶的运动量;施加合理大小的预张力能有效降低船舶的位移量,均衡缆绳张力;建议大船主缆选用钢缆。     

单相接地电容电流的自动补偿

为消除港口供电系统中电缆线路发生单相接地后电容电流对系统的危害 ,采用“直流偏磁式自动跟踪补偿消弧装置”进行补偿。该装置可在线自动跟踪、测量电网的电容电流 ,在发生单相接地故障时自动投入补偿。     

Vertical integration and its implications to port expansion

ABSTRACT

Over the years many shipping lines have established terminal operation companies, with some set up as independent firms. However, port authorities and local governments have not always welcomed external investment and control with open arms. The economic implications and each stakeholder’s best strategies remain unclear. This study develops an analytical model in order to study the effects of vertical integration, with a focus on shipping lines’ investment in ports’ capacity. Modelling results suggest that vertical integration between terminal operator and a shipping line leads to higher port capacity, port charge, market output and consumer surplus. It also reduces delay costs. All these results suggest that vertical integration can be an important source of synergy for the maritime industry. Although vertical integration increases the participating carrier’s output at the expenses of non-integrating rival shipping firms, our numerical analysis suggests that the overall social welfare is likely to increase. Preliminary empirical tests confirm that vertically integrated ports handle more traffic volumes and are associated with better infrastructure and equipment. Therefore, port authorities and government regulators should carefully review the market competition status as well as port expansion plans.     

连云港港25万吨级矿石接卸码头工程总体设计

连云港港25万吨级矿石接卸码头工程是我国目前一次性建设规模最大的矿石码头,是连云港港旗台作业区建设的第一座码头,因此其码头的布置形式、码头前沿线位置、码头面高程和陆域高程的确定尤为重要。文中从总体布置、平面布置等方面论述了该工程的总体设计思路。工程建成后运转正常,为旗台作业区后续工程的建设奠定了基础,提高了我国大型专业化散货码头的工艺水平。     

A continuous berth template design model with multiple wharfs

ABSTRACT

Berth planning plays an important role in improving the efficiency of a container terminal. This study focuses on the berth template problem (BTP), which determines the berthing windows of the calling ships within a planning horizon (e.g. a week) in a cyclical way. As a mid-term tactical decision problem, BTP provides the decision support for a terminal operator to negotiate the contracts with the shipping lines. This study develops an integer programming (IP) model aiming to minimize the total deviation, given the ship-dependent target times preferred by the shipping lines. To validate the model and illustrate the benefits of its use, we perform a numerical experiment based on operational data of a specific container terminal in Southeast Asia. Two IP-based heuristic methods are developed to take into account the decision framework of terminal operators in reaction to demand increases. The experiment results indicate that the model and the solution approaches can enhance the resource utilization and operational efficiency of container terminals.     

输油管线系统压力与阻力的研究与分析

结合天津港石油化工码头输油管路上双金属温度计损坏的情况,分析管路系统变化时的阻力、 受力及振动,得出了温度计损坏原因和解决办法,并对如何减小局部阻力提出了建议。     

惠州荃湾煤炭码头堆场工艺优化比选

结合项目的功能定位和特点,从多方面对散货堆场分别采用平行码头前沿线布置和垂直码头前沿线布置的两种堆场工艺布局形式进行技术、经济分析比较,以达到提高堆取料机单机的作业覆盖范围、充分发挥堆场设备效益的目的,供类似散货堆场设计时参考。     

Internalization of port congestion: strategic effect behind shipping line delays and implications for terminal charges and investment

This paper develops a theoretical model to analyze the congestion internalization of the shipping lines, taking into account the ‘knock on’ effect (i.e. the congestion delay passed on from one port-of-call to the next port-of-call). We find that with the presence of the knock-on effect, liners will operate less in terminals, and an increase of a liner’s operation in one terminal will decrease its operation in the other. If the liners are involved in a Stackelberg competition, whether they operate more or less in a terminal under the knock-on effect depends on the comparison between the marginal congestion costs of terminals. Furthermore, we find that the coordinated profit-maximizing terminal charges are higher than both the socially optimal terminal charges and the independent profit-maximizing terminal charges. When the knock-on effect is small, the independent profit-maximizing terminal charges are set at higher levels than the socially optimal terminal charges; but when the knock-on effect is sufficiently large, this relationship may reverse. Besides, the capacity investment rules are the same for welfare-maximizing terminal operator and coordinated profit-maximizing terminal operator, while independent profit-maximizing terminal operators invest less in capacity. The larger the knock-on effect, the larger this discrepancy.     

海上浮简锚泊分析

首先对浮筒锚泊线进行了受力分析,然后在求得锚泊线方程解的基础上给出最短锚泊线和最小锚距的计算方法。提出锚泊线对浮筒的弹簧作用,给出浮筒纵荡方程,为防止共振给出理论依据。     

碎石桩复合地基在驳岸整治中的运用

因拟建码头前沿线与陆域红线之间距离很近,为保证岸坡稳定和使用期码头结构的正常使用,驳岸段地基处理,设计采用碎石桩复合地基和抗滑桩结合的方式.介绍地基处理方案构想和驳岸前沿线I段地基处理方案.该方案可保证安全,造价最优.