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411.
车辆控制系统CAN总线通信的实施方法   总被引:23,自引:4,他引:23  
程军  崔继波  苟凯英 《汽车工程》2001,23(5):300-305
本文采用SAE J1939通信协议在载货车上实施了CAN总线通信,采用Intel87C196CA单片机实现了它的硬件通信,采用J1939通信协议设计了ABS控制器和变速器控制器的各种数据的辨识位和它们之间的通信过程。  相似文献   
412.
混合仿真技术在车辆电子控制系统快速开发中应用   总被引:6,自引:1,他引:6  
李君  喻凡  殷承良  张建武 《汽车工程》2001,23(5):306-310
本文叙述了利用先进计算机技术和已有的仿真软件,进行车辆电子控制系统快速开发的过程,利用该开发系统对车辆防抱死制动系统(ABS)进行开发,最后把研制的ABS控制器应用于实车进行道路试验,取得较好的效果,使在较少的前期投入和短时期内开发出合格的汽车电子产品以迅速占领市场成为了可能。  相似文献   
413.
用一维不可压缩、非稳态管内流动模型描述公路隧道气流流动与浓度分布,并结合实际的越江隧道,对各种工况下隧道内空气流动状况和污染物浓度分布进行了模拟计算。  相似文献   
414.
循环式燃油系统故障仿真及特征分析   总被引:2,自引:0,他引:2  
介绍了一种船舶柴油机用循环式燃油系统的结构特点,详细分析了这种燃油系统的燃油压力波形特征。对该不同燃油粘度、不同燃油比重和12种典型故障下的燃油喷射过程进行了计算机仿真计算和特征参数的相对偏差分析,揭示了各种故障的燃油压力波形特征及与系统故障的内在联系,分析了各特征参数对不同故障的敏感特性。  相似文献   
415.
船舶综合导航系统仿真技术研究   总被引:1,自引:0,他引:1  
本文以用惯性导航系统(INS)和静电陀螺监控器(ESGM)为中心的综合惯性导航系统为背景,讨论了综合导航系统研制过程中的数学和半实物仿真技术。  相似文献   
416.
柴油机船舶推进装置的建模和实时仿真   总被引:6,自引:1,他引:5  
本文根据准稳态的概念建立了适用于实时仿真的二冲程柴油机船舶推进装置的多阶一性模型。在充分多的试验数据的基础上,结合工作原理建立了各子系统及整个装置的动态模型,这种模型既能反映柴油机内部各参数,精度较高,计算工作量也比较适中。文中提出了一些经验公式,使模拟得以有效地简化。最后,作为实例给出了35000吨油船推进装置的实时仿直  相似文献   
417.
Realistic simulation of underwater scene is always difficult because of the special and complex vision effects in underwater space. Seabed is an important part of underwater environment. This paper describes the methods for seabed scene simulation based on OpenGL. It includes construction of fluetuant terrain based on the random sinusoidal algorithm, simulation of seabed flicker effect by means of circular texture mapping and generation of turbidity effect by using fog techniques. For the application based on the leading high level 3D development environment-Vega, underwater scene simulation is still a difficulty since there is no module for it. Based on the analysis of Vega software and the research on seabed scene simulation methods, a Vega extending module named “Underwater Space” was created through developing module class and extending lynx interface. The module class was designed through developing DLL written in C . The Lynx was extended through developing keyword configure file, GUI configure file and lynx plug-in DLL. The problem that Vega can‘t simulate underwater space, is elementarily resolved. The results show that this module is efficient, easy using, and the seabed scene images am vivid.  相似文献   
418.
This article presents a novel intersection traffic management system for automated vehicles and quantifies its impact on fuel consumption and greenhouse gas emissions of CO2 relative to traditional traffic signal and roundabout intersection control. The developed intelligent traffic management (ITM) techniques, which are based on a spatiotemporal reservation scheme, ensure that vehicles proceed through the intersection without colliding with other vehicles while at the same time reducing the intersection delay and environmental impacts. Specifically, the spatiotemporal reservation scheme provides each vehicle a collision-free path that is decomposed into a speed profile along with navigational instructions. The integration of the developed microscopic traffic simulator with instantaneous emission model, provides improved assessments of the environmental impact of traffic control strategies at intersections. The simulator architecture integrates several ITM algorithms, vehicle sensors, V2V/V2I communications, and emission and fuel consumption models. Each vehicle is modeled by an agent and each agent provides information depending on the specific vehicle sensors. The ITM system is supported by V2V and V2I communications, allowing the exchange of information among vehicles and infrastructure. The data include the estimated vehicle position and speed. Compared with traditional traffic management techniques, the simulation results prove that the proposed ITM system reduces CO2 emissions significantly. The research also shows that these reductions are more significant when the traffic flow increases.  相似文献   
419.
Several significant events between 2007 and 2009 impacted flight demands and the abilities of the three major New York area airports to handle demand. This paper assesses the results of applying a probabilistic simulation method – which isolates the individual contributions of changes in flight demand and changes in airport throughput performance to changes in flight delays – to diagnose how these different events may have caused operational changes at these airports, and in turn, how the results may be used to inform policies for appropriate countermeasures. The analysis revealed two key observations. Firstly, certain patterns in throughput performance shifts caused the most significant delays, and were more likely to have been caused by controller staffing issues rather than caps. Secondly, relatively constant average delays from one year to the next may result from significant demand drops accompanied by large throughput performance degradations at an airport. This suggests that not only operational limitations on capacity encourage airlines to reduce schedules, but that changed demands can also impact throughput performance. Overall, the analysis indicates that caps may not have provided their fully intended delay benefits. Although they successfully reduced overall flight demands at LGA and JFK, they also directly limited throughput performance at critical times, in turn limiting delay benefits. In addition, demands at the busiest times of the day appear to be relatively inelastic to these operational limitations, insofar as demand profiles at EWR and JFK remained “peaky” in 2008 and 2009. Also, the recession was largely responsible for reducing demands at the airports in 2009, but the delay benefits of this were dampened by a corresponding throughput performance degradation. Based on the above observations, a more direct demand management policy combined with policies that focus on maintaining high staffing capabilities at critical times of the day may be considered, to reduce the likelihood of major queue formation on days that do experience sustained demands. The results also suggest that a more flexible caps system, particularly during times of heavy queues, could be explored. Although airport practitioners have keen understandings of how their airports operate, without the support of quantitative analysis tools, it can be more difficult to argue the need for appropriate countermeasures. An analysis such as the one presented here can provide the detailed quantitative substantiation required to build cases for these targeted policy directives and infrastructure investments.  相似文献   
420.
铸轧区的温度分布直接影响着铸轧过程的稳定性和复合板材的质量.针对实验室复合板半固态铸轧试验的特点建立了数学模型,采用有限元法对钢-铝石墨半固态铸轧复合过程的热流耦合问题进行了数值模拟计算,分析了不同浇注温度和铸轧速度下熔池内温度场变化的情况.模拟结果表明,当浇注温度为620℃,铸轧速度在0.6~0.8 m/min的范围内可保证铸轧稳定进行,此结论与试验数据相吻合.该模型可以有效预测凝固前沿位置,为半固态铸轧复合工艺的进一步研究和钢-铝石墨复合板的数字化生产提供了依据.  相似文献   
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