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1.
一种新型的海上溢油处理剂——集油烈和凝油剂最近由青岛海洋大学研制成功。据称,该处理剂是取代传统消油剂极具发展前途的21世纪新型溢油处理剂,可使溢油层在短时间内得到控制并聚集。该项技术经国家科委鉴定认为填补了我国同类技术空白,处国际先进水平。  相似文献   

2.
本文基于航行体超空泡理论和格兰威尔线型设计方法,设计了三种具有不同前部线型的航行体模型.并针对所设计的三种模型和具有锥形前部外型的航行体模型在西北工业大学水洞中进行了前部线形对超空泡生成影响的实验研究.结果表明:超空泡生成速度和空泡成生所需临界通气量与航行体的轴向斜率分布有关,模型表面斜率轴向分布曲线越平坦或变化率越小,越有利于提高空泡的生成速度、减少超空泡生成所需的临界通气量.实验数据显示文中设计的三种格兰威尔前部线型航行体与锥形前部外型航行体相比,生成超空泡所需临界通气量都有明显减小,空泡生成速度有明显提高.文章研究方法为降低超高速航行体超空泡生成所需的临界通气量,提高空泡的生成速度提供了一条技术途径和研究方法.  相似文献   

3.
基于LS-DYNA软件,建立淹没水射流破碎天然气水合物沉积物的拉格朗日-欧拉流固耦合模型,分析射流速度、喷嘴直径和喷嘴间距等对组合射流破碎结果的影响。基于自主研制的水合物替代试样以及相关试验装置,进行淹没水射流破碎天然气水合物沉积物的试验,通过三维扫描仪得到破碎坑形貌,测量了破碎坑尺寸。研究发现:增加射流速度可有效提高射流破碎效率,喷嘴直径对射流破碎坑直径影响明显。对比喷嘴直径为3 mm和4 mm以及4 mm和5 mm射流形成的破碎坑宽度,分别增大了111.66%和123.63%;当射流速度与喷嘴直径一定,喷嘴间距在17~51 mm之间增加时,破碎坑体积先增大后减小,且存在一个最优间距;减小喷嘴直径会增加节流压耗,直径过小还会导致设备精度和寿命降低;射流采掘工具未旋转时产生的射流破碎坑会降低破碎效率和破碎坑壁面的稳定性。这项研究为组合喷嘴射流破碎水合物沉积物提供了参考和依据。  相似文献   

4.
国土资源部近日透露,我国今年首次在珠江口盆地东部海域钻获高纯度新类型天然气水合物可燃冰,分布面积55平方公里,控制储量相当于1000-1500亿立方米天然气。
  可燃冰又称天然气水合物,深藏于大洋底部,目前尚无技术对其进行商业开采,大规模开发可能要在2030年以后才可实现。
  国土资源部下属的广州海洋地质调查局经过近四个月的勘探,通过实施23口钻探井,钻取了高纯度天然气水合物样本。  相似文献   

5.
《江苏船舶》2016,(1):32-34
样品转移卡爪是天然气水合物保压转移装置的重要关键部件,其功能是实现在维持内压的情况下抓取并移动天然气水合物样品管。基于降低对样品的扰动、提高抓取及脱离样品管的成功率等因素考虑,提出一种结构精巧的样品管抓取的卡爪机械结构,并对关键部件进行受力分析。实验表明,该样品管卡爪机构能够有效抓取及脱离样品管,该设备研制成功加快了样品转移装置研制的进展。  相似文献   

6.
10月8日,我国自行研制的首艘天然气水合物(可燃冰)综合调查船在武昌造船厂命名下水。 这艘被命名为“海洋六号”的天然气水合物综合调查船,是武船为广州海洋地质凋查局建造的集多学科、多技术手段于一体的远洋调查船,将主要承担海底天然气水合物质源调查任务,兼顾海洋地质调查、海洋矿产资源调查、  相似文献   

7.
将模糊C-均值(PCM)算法和模糊对向传播神经网络相结合,解决了模糊对向传播神经网络中模糊隶属度函数的自动生成问题,在此基础上结合卫张(Sugeno Tanaka Kang)模糊模型,提出了改进的模糊对向传播神经网络Improved FCP,并给出了学习算法。对两种典型的非线性模型进行实验研究,实验结果表明Improved FCP网络具有良好的非线性逼近能力。  相似文献   

8.
一种基于粗糙集的决策树生成算法   总被引:7,自引:0,他引:7  
针对决策树的构造和修剪通常不能同时进行所产生的效率低下的问题,提出了基于粗糙集理论中知识依赖性的决策树构造方法。利用优先策略,将知识依赖性同时作为属性约简和建树的准则,在决策树预修剪的同时进行节点生成,大大提高了决策树构造的效率。使用Fisher's iris数据集对琏于粗糙集理论中知识依赖性的决策树生成算法和用回归拟合方法的决策树生成算法进行比较。实验结果表明,前者的分类精度和决策树模型的复杂程度要明显优于后者。  相似文献   

9.
选用表面活性剂聚乙烯醇缩丁醛(PVB)和聚乙烯吡咯烷酮(PVP),以及偶联剂KH550、KH570等表面处理剂,来研究体系中添加表面处理剂对溶剂热法合成的CuInS2纳米晶体分散性的影响.利用X-射线粉末衍射仪、EDS能谱、扫描电镜(SEM)和紫外-可见近红外分光光度计对纳米晶体的结构、原子配比、形貌和光吸收性能等进行表征.结果表明:体系中添加少量(总质量的0.1%)表面处理剂制备的CuInS2纳米晶体团聚现象能得到有效改善,其中偶联剂KH570和表面活性剂PVP改性效果佳.  相似文献   

10.
根据天然气水合物的分子动力学分解规律,建立了热激励法开采模型,并运用有限差分法对压力和温度控制方程进行了数值求解。计算结果表明,地层渗透率和井底加热温度对开采过程中地层的压力、温度分布以及气体的产量变化影响较大。由于模型中同时考虑了水合物的分解和再合成反应(可逆反应),因此,天然气的产量随时间呈明显的周期性变化趋势,而且随着时间增长,周期逐渐变长。  相似文献   

11.
正San Francisco,California,June 8-13,2014.OMAE 2014 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to:·meet and present advances in technology and its scientific support;·to exchange ideas and experiences whilst promoting technological progress and its application in industry·to promote international cooperation in ocean,offshore and arctic engineering.In line with the tradition of excellence of previous OMAE conferences,more than 900 technical papers are planned for presentation.Outreach for Engineers Specialty Forum This Specialty Forum is designed for students and professionals who may not be familiar with the Ocean and Offshore industry,as well as those who have just recently specialized in this field.  相似文献   

12.
Errata     
正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.  相似文献   

13.
14.
正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to: meet and present advances in technology and its scientific support;  相似文献   

15.
联合作战计划和执行系统   总被引:2,自引:1,他引:1  
全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划:时间不限的精密预案计划生成作战计划、方案计划或职能计划;时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础,加速应付危机的能力。  相似文献   

16.
Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.  相似文献   

17.
正19–24 October 2014 SingaporeCONFERENCE THEMES The overall aim of the ICHD Conference is to provide a forum for participants from around the world to review,discuss and present the latest developments in the broad discipline of hydrodynamics and fluid mechanics.The first International Conference on Hydrodynamics(ICHD)was initiated in 1994 in Wuxi,China.Since then,9 more ICHD conferences were held subsequently in Hong Kong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,Shanghai and St Petersburg.Evidently the ICHD conference has become an important event among academics,researchers,engineers and operators,working in the fields closely related to the science and technology of hydrodynamics.The 11th ICHD will be held in Singapore in 2014.  相似文献   

18.
正November 4-6,2014Moody Gardens HotelConvention Center/Galveston,TX The Deepwater Operations Conference and Exhibition is celebrating its 12th anniversary this year.This growing event will continue the tradition of excellence in addressing operational challenges involved in developing deepwater resources.We will return to the Moody Gardens Hotel and Convention Center on November 5-7,2014 in Galveston,Texas.  相似文献   

19.
In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama?
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou).  相似文献   

20.
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.  相似文献   

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