首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
研究了非线性非保守动力学系统的近似Birkhoffian化.基于等效线性化方法,通过平方误差累积最优原理,给出了非线性非保守系统的等效线性化系统.运用Santilli第一方法,得到Birkhoff函数为系统总能量的近似Birkhoff系统.最后,应用文中提出的方法,给出了两类非线性非保守系统的近似Birkhoffian方程.  相似文献   

2.
船舶管网系统水力特性是水力计算、系统调试、系统优化设计的理论基础。借助图论这一数学工具,建立了管网系统水力特性的数学模型。在该模型的基础上,利用逐渐增加管网系统回路并逐步迭代计算新增回路阻力系数和流量的思想,提出一种无需给定迭代初值的管网水力计算方法,通过对实船压载水系统进行实时仿真计算,验证计算方法的有效性;提出了一种管网系统调试方法,利用滑油管网系统调试,验证了该方法的合理性。  相似文献   

3.
研究了一个新的混沌系统的混沌同步问题。基于Lyapunov稳定性理论,采用非线性反馈混沌同步方法,给出了该系统实现自同步的充分条件以及控制律参数的取值范围;结合参数自适应混沌同步方法,实现了该混沌系统与统一混沌系统的异结构系统快速同步。数值仿真证明了该方法的有效性。  相似文献   

4.
为了获得更高的船舶集中空调系统能耗预测结果,提出了基于最小二乘支持向量机的船舶集中空调系统能耗预测方法。首先分析船舶集中空调系统能耗预测研究进展,并设计了船舶集中空调系统能耗预测原理,然后采集船舶集中空调系统能耗历史数据,并采用最小二乘支持向量机对船舶集中空调系统能耗历史数据进行学习,获得船舶集中空调系统能耗预测模型。最后在相同环境下,与其他船舶集中空调系统能耗预测方法进行了对比测试。结果发现,最小二乘支持向量机的船舶集中空调系统能耗预测精度超过90%,误差控制在10%以下,可以满足船舶集中空调系统能耗控制的实际应用要求,预测误差远小于其他船舶集中空调系统能耗预测方法,体现了本文方法的优越性。  相似文献   

5.
文章针对舰船主动力系统维修训练存在的问题,提出采用虚拟维修的方法进行主动力系统维修训练,分析了系统的功能需求,研究了系统方案和关键技术,并以此为基础开发了某主动力系统虚拟维修训练系统。文章为舰船主动力系统的维修训练提供了新的方法,并为舰船装备的现代化维修训练手段提供了一定的参考。  相似文献   

6.
针对具体的自动镀膜机系统建立了系统的数学模型,对一种Ⅰ型间接自适应模糊控制方法进行了改进。该方法优化了参数自适应律,能够确保系统的稳定并且抑制了抖振,跟踪曲线平滑。仿真结果表明该方法具有良好的跟踪性能,说明了该方法的有效性和实用性。  相似文献   

7.
针对船舶通信系统具有的不确定性与模糊性,传统的评价方法难以获得较高的评价精度,提出了一种基于模糊理论的船舶通信系统风险评价方法。首先结合船舶通信系统信息安全的需求,建立船舶通信系统风险评价指标体系,并参考专家意见,利用层次分析法确定各风险评价指标体系的权重,然后确定船舶通信系统风险的模糊评语集,最后进行仿真试验。试验结果表明,模糊理论方法的船舶通信系统风险评价的准确率高于对比方法,验证了本文方法有较高的工程实用性和有效性。  相似文献   

8.
针对捷联惯性导航系统中的陀螺温控系统存在纯滞后的特性,本文提出了用人工神经网络方法来在线辨识系统中的纯滞后,仿真结果表明了该方法的有效性。  相似文献   

9.
一个新混沌系统的异结构反同步   总被引:2,自引:0,他引:2  
研究了一个新的三维混沌系统的异结构反同步问题.基于Lyapunov稳定性理论,采用主动控制方法,实现了一个新混沌系统分别与Lorenz系统、Chen系统和La系统的异结构反同步.数值模拟证明了该方法的可行性和有效性.  相似文献   

10.
相对于传统船舶动力推进方式,船舶动力推进系统具有能耗小、性能好的优点,暂态特性直接影响船舶动力推进系统的工作性能,当前方法无法有效地分析船舶电力推进系统暂态特性,为此设计了基于数据挖掘的船舶电力推进系统暂态特性研究方法。首先对船舶电力推进系统暂态特性变化特点进行分析,建立船舶电力推进系统暂态特性的数学模型,然后通过数据挖掘方法对船舶电力推进系统暂态特性进行研究,分析扰动因素对船舶电力推进系统暂态特性的影响,最后通过仿真实验测试研究方法的有效性。结果表明,本文方法可以高精度船舶电力推进系统暂态特性,提高了船舶电力推进系统的可靠性和工作稳定性。  相似文献   

11.
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   

12.
13.
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   

14.
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   

15.
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   

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.
桥梁防撞设施物理模型试验   总被引:1,自引:0,他引:1  
物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。  相似文献   

18.
詹明  郑厅厅 《港工技术》2010,47(4):17-19,23
印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。  相似文献   

19.
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   

20.
开放式数据挖掘系统模型   总被引:2,自引:0,他引:2  
目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较,都与国外软件存在着较大的差距。随着数据仓库技术的普及,数据挖掘应用的需求越来越强烈,如何缩短这种差距,研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型,该系统模型从可扩展性、可重用性、易用性等方面得到了加强。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号