Determination of the transportable moisture limit of iron ore fines for the prevention of liquefaction in bulk carriers

In 2013, over 500 million metric tons of Iron Ore Fines (IOF) were transported around the world using bulk carriers. Under certain conditions IOF, while being transported, can possibly undergo liquefaction. Since 2006, there has been eight reported bulk carrier casualties possibly caused by the liquefaction of IOF. The objective of this study is to evaluate, compare and verify the limitations and relevance of the Proctor/Fagerberg, Flow Table and Penetration test methods that are used to determine the Transportable Moisture Limit (TML) of IOF. The TML is the maximum gross water content that bulk cargoes, including IOF, may contain while being transported at sea without being at risk of liquefying. A thorough literature review, along with laboratory research, was carried out to compare the TML results from the three leading test methods to determine whether they produce reliable results when testing IOF. The study concludes that the three test methods, as stated in the 2012 International Maritime Solid Bulk Cargoes Code, are unverified and therefore not appropriate for testing IOF. This is due to the variation in the results produced by the three test methods and also due to the difference in the physical properties of IOF when compared with the materials that were originally intended for testing. It is noted that the TML alone may not control the potential liquefaction of IOF and further studies, regarding the physical properties and system variables, which cause the material to liquefy, are required to determine the liquefaction potential of IOF.     

热泵技术在船舶领域的应用

介绍了船用水源热泵系统的设计思路、设计方法 ,以及具体的设计方案。评价了水源热泵系统优点。依托某两型客船的研究、设计与建造,从船型需求入手,通过了解这两型客船的营运区域、舒适度要求等,并从设计原理、控制逻辑、供热系统等几个方面展开了设计。同时对比同型船常规供热系统的设计方案,分析比较节能效果,确定了最合适的节能系统。     

一种优化的船体外板三维点云数据提取方法

针对水火弯板机检测系统中船舶外板三维点云数据自动提取过程存在边缘噪点、板下贴合垫木识别效率低以及外板边缘拟合等问题,提出一种优化DBSCAN聚类算法,首先根据现场加工环境精简点云,利用网格划分来建立外板点云拓扑模型,然后根据DBSCAN密度聚类算法搜索出外板点云,最后采用最小二乘法进行边缘拟合。结果表明,该算法能有效识别外板边缘,提取出外板点云。     

单点系泊FPSO系泊缆疲劳寿命研究

采用准动态方法对单点系泊FPSO进行系泊分析,并采用T-N曲线和Miner线性疲劳累积损伤理论以及雨流计数方法对系泊系统进行疲劳分析,研究每一根系泊缆不同位置处的疲劳寿命,研究发现每一根系泊缆触地点位置的疲劳寿命最短。     

达布定理的一个应用

应用达布定理,纠正了不定积分计算中的一个错误。     

浅议高速公路通信系统电源防雷器设置方法

介绍高速公路通信系统电源防雷器设置方法,及通信系统电源防雷器件在选择和安装中的注意事项.     

探索港口发展现代物流的切入点

介绍了港口发展现代物流的两个切入点,即从宏观上切入,逐步提高港口的国际竞争能力;从微观上切入,稳步提高港口经济运行质量和效益。阐述了发展现代物流也是港口自身实现跨越式发展的必然途径和战略目标。     

城市道路水泥混凝土路面锯齿形偏沟设计方案

水泥混凝土路设计时,遇到设计纵坡小于0.3%,按规范要求设置锯齿形偏沟或采取其他排水措施,过去常采用缩短雨水口的间距办法,来解决排水问题,实际上此措施是不能很好地解决排水问题的.提出:仅在道路边缘50cm范围内设置偏沟的办法(水泥混凝土路面一般不设置平石),雨水口距离可保持40m,不再要加密雨水口,缩短雨水口的间距,同...     

美日汽车起动机性能指标解析

从起动机设计的角度，分析影响起动机主要性能指标的各项因素和调控规律。重点论述如何调整设计和制造工艺，使产品全面达到满足发动机和整车配套的技术要求。     

光电式钢轨磨损实时检测系统

采用近红外线状光源、CCD及计算机图像处理等技术,实现钢轨磨损检测系统的软硬件设计。应用三圆柱光学透镜联合对一点式激光进行色散,得到光强分布较均匀的线状激光光源。用高分辨率(752×782)CCD面阵摄像机实时采集钢轨扫描图像,经过A/D变换输出给图像处理系统。图像处理系统根据钢轨的形状和特点,选用最佳的模型和计算方案进行图像处理,对照标准钢轨断面图像快速、准确地计算出钢轨面的磨损值,判断钢轨受伤程度。系统在限速80 km.h-1条件下对钢轨断面的实时检测结果表明,系统符合设计要求,精度达到0.1 mm。