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61.
基于有限元法,对某穿梭油船货油泵电机基座进行多工况强度分析与模态分析,计算其固有频率,并对比主机、螺旋桨等激励源频率,分析共振可能性.在分析过程中采用点质量方式简化电机质量,以壳单元代替基座实体模型,通过DesignModeler软件建立模型、划分网格和约束边界条件,显示应力和变形计算结果,对设计方案的评定和优化具有较...  相似文献   
62.
刘海蛟  张少雄 《船海工程》2013,(6):33-37,41
为准确评估超规范的载重3600t大通舱干货船的弯扭强度及变形水平,采取全船水动力分析及全船有限元直接计算的方法,对各工况下的主要载荷参数进行长期预报,推导出对应等效设计波各参数。根据等效设计波求出各工况全船所受的波浪诱导动载荷,施加到全船有限元模型上,进而对船体弯扭强度及变形水平进行评估。比较了单舱船及货舱中部设一道横舱壁的两舱船,得出单舱船屈曲强度不足的结论,并提出改善屈曲强度的方案。  相似文献   
63.
Navigation safety on coastal waters is an extremely important issue. Fatigue is an important factor threatening navigation safety. Considering that the vessel type is an oil tanker, such a threat is not posed only to the crew but also to the environment. Most of the tankers navigating coastal waters are in the small tanker category. Therefore, this study examined the working and resting hours of the deck officers in the oil tankers navigating coastal waters. The study utilized the ISF Watchkeeper 3 program for assessing and interpreting the working periods. The study reached the conclusion that the first and second officers in particular are working under unsuitable conditions. To improve the working conditions of the deck officers, effects of additional cargo officer on board was investigated. This study is in quality of recommendation. The study elucidated that the cargo officer practice determines the working and resting hours of deck officers, in the work on the oil tankers, and compliance with the related conventions.  相似文献   
64.
Predominance of containerised mode of transport for export of general cargo has influenced the mode choices on the inland segment. Prior to containerisation the general cargo for export moved to ports invariably on road in break bulk form. Growth of containerisation led to development of inland terminals enabling an exporter to obtain export clearance at the inland points. This process facilitated an exporter to move cargo either in break bulk or in containerised form, and as inland terminals facilitated aggregation an exporter could move cargo either by road or rail. Thus containerisation increased the inland transport options for an exporter from one to three. The paper develops discrete choice models in the Indian context for inland movement of containerised export cargo. Primary data was collected from 124 export firms through a structured questionnaire. This data is supplemented with data from transport firms and terminal operators. Using the above data, a nested logit model with rail container and road truck in one branch was found to predict the mode choice behaviour best. Amongst the transport attributes, total cost and total transit time were found to be influencing the mode choices significantly. The study however did not find the effect of reliability and loss and damage significant. In addition, the model also predicts that non transport attributes - like the percentage of letters of credit that materialise with inland way bills and the value of export benefits that materialise after export - are important in the mode choice decision.  相似文献   
65.
左德华  包建新 《中国海事》2013,(10):45-46,57
文中分析了部分小型油船利用双层底舱装运货油为多赚运费的违章行为,指出了违章原因,并提出了相应的建议。  相似文献   
66.
文中专题分析2009年MAI(POL公约附则I修正案“关于防止油轮间海上货油过驳期间造成污染”的履约要求和我国海事监管存在的问题,并提出相应对策建议,以期全面履约和实现对我国管辖海域内的油船间货油过驳作业的有效监管  相似文献   
67.
为贯彻新修订的《危险化学品安全管理条例》,对港口危险货物作业场所现状进行分析.阐述危险货物相关概念.阐明危险货物、危险化学品的区别与联系.统计全国现有危险货物码头、库区及堆场,以及移交港口行政管理部门的储罐的数量,为港口行政管理部门进行安全监管提供理论依据.  相似文献   
68.
This paper models the dynamic competition between major cargo airports from the time series perspectives of long-term equilibriums and short-run dynamics. We first apply a unit root test to examine the stationarity of cargo throughput data. Airports are then analysed pairwise by region to test their equilibrium relationships through cointegration analysis. Meanwhile, we also utilise the error correction model to investigate the short-run impacts of cargo traffic between the airports. According to our findings, there are four positive long-term equilibriums, one positive short-run dynamic and three negative short-run dynamics in Asia. In addition, the airports in North America are found to have four positive long-term equilibriums, three negative long-run equilibriums, seven positive short-run impacts and three negative short-run impacts. As these dynamic relationships imply competition between cargo airports, our study can provide airport authorities with the reference to develop their long-term strategies and short-run operational plans.  相似文献   
69.
通过介绍目前港口铁路大宗散装货物装车作业工艺的三种传统方式及其优缺点,重点推介南京港集团新生圩港区采用的一种自主创新的集成式全功能自动装车系统成套技术,与传统装车工艺相比具有高效率、节约成本、节能、环保等特点,推广应用前景非常广阔.  相似文献   
70.
在油轮的货仓系统中,通常都装有PV阀(中文名字叫高速压力-真空阀),以便油轮在装卸过程中和营运过程中起到保护货仓的作用,以防止安全事故的发生。但在实际过程中,如果有货油进入该阀门或者连接管路后,使有可能使其失效。  相似文献   
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