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31.
黄栋 《港口科技》2008,(5):32-34
上海港外高桥港区进行轮胎式集装箱起重机驱动油改电项目,产生了用何种方法接地问题。对供电铁塔到RTG(Rubber-Tired Container Gantry Crane)处接地问题进行探讨。通过计算,找出了合适的接地模式,既能保障人身安全,又能让设备正常运行。  相似文献   
32.
An optimized methodology to design a more robust torpedo shell is proposed. The method has taken into account reliability requirements and controllable and uncontrollable factors such as geometry, load, material properties, manufacturing processes, installation, etc. as well as human and environmental factors. The result is a more realistic shell design. Our reliability optimization design model was developed based on sensitivity analysis. Details of the design model are given in this paper. An example of a torpedo shell design based on this model is given and demonstrates that the method produces designs that are more effective and reliable than traditional torpedo shell designs. This method can be used for other torpedo system designs.  相似文献   
33.
WIT Electronic Fuel System Co., Ltd. has developed a new fuel injector, the Electronic In-line Pump (EIP) system, designed to meet China's diesel engine emission and fuel economy regulations. It can be used on marine diesel engines and commercial vehicle engines through different EIP systems. A numerical model of the EIP system was built in the AMESim environment for the purpose of creating a design tool for engine application and system optimization. The model was used to predict key injection characteristics under different operating conditions, such as injection pressure, injection rate, and injection duration. To validate these predictions, experimental tests were conducted under the conditions that were modeled. The results were quite encouraging and in agreement with model predictions. Additional experiments were conducted to study the injection characteristics of the EIP system. These results show that injection pressure and injection quantity are insensitive to injection timing variations, this is due to the design of the constant velocity cam profile. Finally, injection quantity and pressure vs. pulse width at different cam speeds are presented, an important injection characteristic for EIP system calibration.  相似文献   
34.
基于半履带气垫车工作原理和原理样机建立了其虚拟样机模型.对虚拟样机模型的悬架和气垫系统进行调试,并在软地面环境下进行了仿真.结果表明,结合半履带和气垫技术可提高车辆在软地面上的通过性.  相似文献   
35.
基于微型智能传感器的汽车轮胎压力监控系统   总被引:2,自引:0,他引:2  
何茂先  殷晨波  涂善东  董云海  杨敏 《汽车工程》2006,28(8):771-773,778
介绍了基于微型智能传感器的直接式轮胎压力监控系统的构成和原理,并讨论了微型传感器数据的读取、微机械加工等关键技术。  相似文献   
36.
分体冷却式柴油机缸盖水套的CFD分析   总被引:6,自引:1,他引:6  
利用CFD技术对一高速柴油机缸盖水套进行了分析。介绍了缸盖水套结构调整的基本原则及其计算网格的选取方法,并对3种方案的缸盖冷却流场进行了分析。指出,进一步减小沿进气道侧两缸相邻区域连接截面的面积,可以显著减少沿该侧的冷却液流量,增加沿着排气道侧和喷油器侧的冷却液流量。如在缸盖底部排气门侧加导流盘结构,其冷却效果更好。  相似文献   
37.
国外钢板在轿车发展中的作用   总被引:1,自引:0,他引:1  
董瀚  李桂芬 《汽车工程》1996,18(6):373-377,372
本文从法规限制,市场需求和生产制造等方面评述了轿车工业面临的压力,论述了钢板用于制造轿车壳体的特点,根据轿车材料的选择原则,无论是近期还是未来,钢板仍将是轿车壳体的主要材料。针对轿车壳体的应用,简述了薄钢板,镀层钢板和复合夹层减振钢槔的现状和发展趋势。  相似文献   
38.
城市轨道交通的快速发展使轨道交通高技能人才的需求常年维持在高位,如何培养更加符合企业用人需求的轨道交通高技能人才是相关职业院校的共同课题。通过分析轨道交通高技能人才培养现状并结合本专业建设经验,总结出依托"校内+校外"实训基地双平台建设,深化校企合作,产融合力,实施"基地共创、学生共培、师资共建、研训共享、文化共融"的"五共"人才培养模式,提升轨道交通高技能人才的培养质量。  相似文献   
39.
以HCCI燃烧过程为主要研究对象的模拟燃烧系统   总被引:1,自引:0,他引:1  
所论述的模拟燃烧系统是针对均质混合气压燃特性试验研究开发研制的装置,主要由燃烧系统主体部分、混合气配给系统等组成。该装置具备定压燃烧过程、复合燃烧过程以及定容燃烧过程的研究试验功能,且具有良好的边界条件可控性。燃烧系统压缩终了压力可达到2.6MPa,活塞最高速度为5m/s,平均速度为2.18m/s。  相似文献   
40.
Surveys of behavior could benefit from information about people’s relative ranking of choice alternatives. Rank ordered data are often collected in stated preference surveys where respondents are asked to rank hypothetical alternatives (rather than choose a single alternative) to better understand their relative preferences. Despite the widespread interest in collecting data on and modeling people’s preferences for choice alternatives, rank-ordered data are rarely collected in travel surveys and very little progress has been made in the ability to rigorously model such data and obtain reliable parameter estimates. This paper presents a rank ordered probit modeling approach that overcomes limitations associated with prior approaches in analyzing rank ordered data. The efficacy of the rank ordered probit modeling methodology is demonstrated through an application of the model to understand preferences for alternative configurations of autonomous vehicles (AV) using the 2015 Puget Sound Regional Travel Study survey data set. The methodology offers behaviorally intuitive model results with a variety of socio-economic and demographic characteristics, including age, gender, household income, education, employment and household structure, significantly influencing preference for alternative configurations of AV adoption, ownership, and shared usage. The ability to estimate rank ordered probit models offers a pathway for better utilizing rank ordered data to understand preferences and recognize that choices may not be absolute in many instances.  相似文献   
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