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1.
汪玉  冯奇  王麒越 《船舶力学》2004,8(3):124-132
对于艇用动力机械设备,正确建模是设备抗冲隔振设计中的一个重要步骤.当系统带有刚性限位装置时,设备可用刚体模拟,隔振器用弹簧力和阻尼力替代,则该系统具有三种非线性因素,本文针对这三种非线性因素究竟是否可以忽略开展定性及定量研究.在本文中,艇用动力机械设备抗冲隔振系统作为一个碰撞-振动-系统(Vibro-impact-sys-tem)研究,本文导出该系统的以碰撞-庞加莱-映射(Impact Poincaremap)描述的零级近似与一级近似模型.实例分析指出:零级近似模型掩盖了可能出现的混沌现象;同时,通过分岔图(Bifurcarion diagram)分析指出,限位器限制行程将影响分岔区域在图上的位置.  相似文献   

2.
考察了苯丙酮在手性胺膦配体与[IrHCl2 (COD)]2组成的催化体系下不对称转移氢化合成(S)-(-)-1-苯基-1-丙醇的反应,通过正交实验考察了反应温度、n(底物):n(铱催化剂)、n(铱催化剂):n(手性配体)和碱用量对反应的影响.结果表明,在异丙醇中,利用该体系催化苯丙酮反应6h后,反应转化率可达94.5%,对映选择性(ee)达96.0%.  相似文献   

3.
通过工程实例,介绍通过技改后的物化-气浮-生化-过滤法处理印染废水的效果及主要设计参数。运行结果表明出水水质达到广东省地方标准《水污染物排放限值》(DB44/26-2001)第二时段一级标准,该工艺在印染废水处理中达到良好的处理效果。  相似文献   

4.
新增的航线:6月份开通亚洲地中海捷运(AMX)航线,共投入8艘3000TEU型船。年运力156000TEU。沿途挂靠大边、天津、青岛、上海、宁波、厦门、香港、赤湾、巴生港、SALALAH、比雷埃夫斯、那不勒斯、热那亚、巴塞罗纳、巴伦西亚、SALALAH、廉差邦、香港、大连。  相似文献   

5.
近年来由于能见度不良导致的海上事故不断增多。本文分析了导致事故发生的主要原因。从人-机-环-管理论的角度提出了一些对策,从而为减少船舶在能见度不良时发生海上碰撞事故的发生提供了一些理论依据。  相似文献   

6.
基于系统安全工程学的港航通航安全评价   总被引:1,自引:0,他引:1  
本文将港航通航安全评估问题归于系统安全工程学范畴,阐明“人-机-环境-管理”(MMEM)系统理论是其基础,据此提出了港航通航安全论证的系统安全工程学框架。  相似文献   

7.
以极地运输船舶的首部作为研究对象,建立基于流固耦合算法的船-水-冰耦合技术对三维船首与冰体碰撞的结构响应问题进行研究,成功解决了船体、冰体与流场、船体与冰体之间的耦合,考虑了碰撞过程中船体与冰体的同步损伤,并结合非线性有限元软件Ls-dyna对比分析了冰体质量、船冰碰撞角度等撞击参数的结构响应问题,分析了不同碰撞工况下船舶撞击冰体后损伤变形、碰撞力等方面的变化特征,对分析船舶与冰体碰撞的结构性能具有参考价值。  相似文献   

8.
分数覆盖图     
设G是一个图,并设h是定义在图G的边集E(G)上的一个函数,使对任意的e∈E(G)有h(e)∈[0,1].令dhG (x)=∑e(∈)xh(e),则称dhG (x)是G中顶点x的分数度.若h满足对任意的x∈V(G)有g(x)≤dhG (x)≤f(x),则称h是G的一个分数(g,f)-因子.如果对图G中的任何两条边e1和e2,G都有一个分数(g,f)-因子h满足h(e1)=1和h(e2)=1,则称图G为分数(g,f)-2-覆盖图.本文给出了一个图是分数(g,f)-2-覆盖图的充分必要条件.  相似文献   

9.
武器装备的可靠性管理和对策   总被引:2,自引:0,他引:2  
介绍了可靠性工作发展的简史,详细叙述了可靠性管理的内涵及如何实施,提出了舰船武器装备开展人-机-环境系统的研究,提升可靠性管理水平的对策。  相似文献   

10.
11.
为了满足仿真系统中智能兵力的智能性和反潜战军事领域仿真资源的可重用性要求,针对现代水面舰艇反潜作战特点和系统设计的新需求,结合模块化建模和多Agent建模2种方法,从宏观和微观角度对水面舰艇仿真平台进行了功能分析;划分了舰艇平台系统模块,建立了舰艇平台层次多Agent模型;利用XML技术在HLA基础上进行了水面舰艇平台的联邦成员设计,分析了联邦成员信息交互关系,完成了各种Agent的构造和决策设计。从而满足了系统仿真粒度的需求,提高了系统仿真平台模型资源可重用性、灵活性和可扩展性。  相似文献   

12.
航海风险识别、评估和控制   总被引:1,自引:0,他引:1  
因航运业高速发展和海员职业流动性加快,导致全球高级船员紧缺,已引发高级船员提升周期缩短、航海经验不足等现象。航海事故造成人员伤亡、财产损失和污染海洋环境等已严重威胁公共安全,航海事故预防和风险控制越来越受到人们关注。船舶海上事故频发,与船员对海上风险,尤其是船员对人为因素与事故的关系的认识不足有关。通过重点介绍航海风险,提高船员对本船和自身存在的风险意识,采取相应的防范措施。  相似文献   

13.
电子计算机技术、微电子技术、激光技术、空间技术等新技术的发展与应用,以及测绘科学技术的进步,为工程测量技术进步提供新的方法和手段.阐述现代工程测量仪器的发展状况,介绍与展望地面测量仪器和CPS定位等空间技术在工程测量中的应用和发展.  相似文献   

14.
In order to understand characteristics of low-frequency motions of ships moored inside ports and harbors, analysis on actual cargo handling logbook of stevedoring services company, including events of interruption of cargo handling, and countermeasure for ship mooring problems are investigated by field observations at two ports and numerical simulation on moored ship motions. First model port concerns with interruption of cargo handling due to the low-frequency motions. Second model port relates to a resonant effect of long-period waves or harbor oscillations, and its countermeasure by mooring system. From the investigation, it is confirmed that the low-frequency motions of ships are induced by a resonance between surge motions and long-period waves or harbor oscillations and an asymmetry in the mooring system, and affect safe ship mooring and operation efficiency of cargo handling in ports and harbors significantly.  相似文献   

15.
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   

16.
The evolution of maritime logistics as an emerging discipline has resulted, to a large extent, from the increasing and varied demands of shippers and customers and the rapidly changing role of ports in the context of supply and logistics chains. Scholars are becoming increasingly aware of the need to integrate logistics and supply chain management concepts in the maritime transportation chain and operations. This article aims to provide a review and foundation for understanding the domain of maritime logistics and to assess its potential as an emerging discipline. To do so, a framework for understanding the various aspects of maritime logistics strategy and implementation is developed. A synthesis of the existing knowledge on maritime logistics is done by integrating diverse explorations forming the basis of this framework. We draw upon the literature on maritime transport and ports and primarily theliterature that analyses concepts by adopting an economic or management perspective.  相似文献   

17.
本文通过对现有的某船用五螺杆泵的频谱特征和振动特性进行分析,找出主要振动噪声源,通过改进进口流道面积,并对现有的螺杆加工工艺进行研究和优化改进,改进后的设计通过样机的制造,并经过试验对比分析,进一步验证方法的可行性和预期减振效果。  相似文献   

18.
本文结合舰船机电控制系统特点和测控技术领域PLC和Labview两者优点,基于字节流数据包的数据灵活性,设计PLC和Labview通信数据包模型,并遵循模块化程序设计原则完成通信接口程序设计,解决舰船机电系统集中控制器和人机接口数据交互的描述问题和通信接口程序通用性问题。最后,通过实例验证设计的数据包模型和通信接口程序能够实现数据快速可靠安全的交互。该技术可应用于舰船综合监控系统和类似系统的软件开发。  相似文献   

19.
A few cities in some of the larger developing countries in Latin America and Asia have made increasing use of multi-year concessions or franchises, competitively awarded to private companies, for construction and operation of urban transport infrastructure and for provision of public transport services. In view of the strong prospective growth of developing-country cities with large transport needs, and the rise in the emerging economies of potential new sources of private capital, it is important to see how effective PPP has so far been in this area. The experience is analyzed principally by thorough comparative review of what has actually happened for some of the main users to date: Bogotá, Santiago, São Paulo, Seoul, and several cities in both China and India. Despite delays and mistakes that have been made in development of most of the projects, the overall results, already delivered and in prospect, are very positive and urban public transport is benefiting substantially, with significant side effects on poorer people's access to work and to services, air pollution levels and road accident rates. The widest and most important advantage of the PPP arrangements, as compared with more conventional short-term contracting, is found to be the innovations, technical and managerial, developed, and, in particular, the mutual capacity building of the countries' private and public sectors and their more effective interaction. The experience in the six countries covered suggests that other developing-country cities may be best assisted to develop sound urban transport PPPs more rapidly through provision of help on chosen items among 7 elements that have proved particularly crucial but sometimes weak in the projects reviewed: Civic consultation systems, Land-use/Transport strategic planning, Land/property market management, Monitoring systems, Progressive policies, Economic regulation, and Public institutional framework for PPPs.  相似文献   

20.
The objective of this article is to take stock of integrated management in the Canadian North, assessing its contribution to the advancement of knowledge and practice regarding the role of indigenous knowledge and community-based monitoring. This is done in three steps. (1) The Beaufort Sea, designated a Large Ocean Management Area under Canada's Oceans Action Plan, is used as an example of a consultative planning process, with special attention to indigenous peoples. (2) How specifically can indigenous knowledge contribute to integrated management? The problem of Arctic marine food web contamination is used to illustrate the strengths and limitations of traditional ecological knowledge and its relationship to science. (3) The discussion of community-based monitoring relies on Voices From The Bay study involving the Inuit and Cree of Hudson and James Bay, and Inuit observations of climate change study in the Canadian western Arctic. The examples together address integrated coastal management and the health of ocean ecosystems, showing how stakeholder participation and knowledge helps widen the range of knowledge to understand and help monitor environmental change.  相似文献   

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