基于RMA方法的汽车车身CAN总线优化设计

针对汽车车身控制信息的高实时性和车身CAN系统扩充的高灵活性等特殊要求,介绍用于实时系统分析的速率单调分析(RMA)方法,在原总线利用率、信息最坏响应时间等实时性指标基础上引入总线扩展灵活性因子进行车身CAN总线方案的寻优设计,并以典型汽车车身控制系统为例,对单信号方案和信号组合方案进行实时性和扩展灵活性对比分析,在线试验结果验证了理论分析数据的正确性。     

双横臂独立悬架ADAMS建模及运动特性分析

利用ADAMS建立了某轻型车完整的双横臂独立悬架运动学仿真模型,为反映车辆的真实行驶工况,对左、右车轮测试平台分别创建了随机激励。通过仿真分析,揭示了运动特性参数在悬架运动过程中的变化规律,并对原导向机构存在的问题进行了优化计算。结果表明,前轮定位参数在优化前、后的变化量较小,均在设计要求的范围内;轮距和前轮侧向滑移量的变化较大,优化后二者都在理想的范围内变动,达到了预期优化目标。     

基于改进粒子群算法的机组经济运行的博弈

在电力市场下如果能够根据实时电价求出在该电价下机组经济运行状况,可以给发电公司权衡报价风险和企业利润提供极大的帮助.如果发电公司仅依据发电成本报价,在参与竞价上网时会因缺乏灵活性而造成机组被迫频繁停机和利润空间的浪费.为此,根据企业利润最大化原则建立机组经济运行数学模型,并用改进粒子群算法对模型优化求解.通过实例分析与传统方案的预测结果进行比较,说明其效果的优劣.其给发电公司决策提供更为灵活,有效的方法.     

基于近似模型的车辆操纵稳定性及平顺性的优化研究

简述了基于近似模型的车辆操纵稳定性及平顺性的优化设计方法.利用多体动力学软件ADAMS/Car建立了某轿车整车多体动力学模型,并确定了车辆操纵稳定性及平顺性的评价目标.以悬架弹簧刚度、减振器阻尼特性和横向稳定杆刚度为设计变量,利用近似优化数学模型对该轿车进行了操纵稳定性和行驶平顺性的多目标优化计算.结果表明,近似模型技术对于汽车性能的平衡优化是一种十分有效的方法.     

Optimization of bus stop placement for routes on uneven topography

The improvement and expansion of public transport is an increasingly important solution to the high congestion costs and worsening environmental impacts of the car dominated transport systems seen in many cities today. The intelligent design of stop locations is one way to improve the quality of PT and thereby improve its ridership. Stop placement is a relatively complex task as it involves a trade-off between two competing goals; accessibility and operation; however this trade-off can be made explicit using an appropriate mathematical model. Many such models have been developed in the literature, however none consider the effects of uneven topography. Topography is an important but often neglected factor in the design of public transportation systems, with the potential to have a significant impact on the accessibility, operation and planning of a transit service. In this work a mathematical modelling approach to bus stop placement is developed which includes considerations of uneven topography in three ways; (1) Its effect on walking speed; (2) Its impact on the attractiveness of an access path to a transit service; and (3) Its effect on acceleration rates at stops. Because of the complexity of the model developed, a heuristic evolutionary algorithm’ is employed to approximate an optimal solution to the model. Finally, the model and solution method are applied to a case study in the Auckland CBD area in New Zealand.     

Ship service life extension considering ship condition and remaining design life

Reliable and continuous operation of ships is vitally important to the decision-makers. Driven by the rising cost of newbuilding ships, maintenance actions are needed on existing ships to ensure safe and enduring service beyond their initial design life. Extending ship service life can provide economic operating profit and promote sustainability. Meanwhile, ships during their extended service life may involve higher failure risk and additional maintenance expenditure. Therefore, a cost-benefit evaluation is imperative for determining the optimal duration of service life extension (SLE) and the associated maintenance actions. In this paper, a novel method for this purpose is proposed. Two cost-benefit indicators, benefit-cost ratio (BCR) and net present value (NPV) are used to optimize the duration of SLE. Using Bayesian updating, information on the remaining design life and the structural condition at the SLE decision is incorporated into the optimization process to better inform SLE decision-making. The proposed method is illustrated by a fatigue-sensitive very large crude carrier (VLCC) at both structural component and structural system levels.     

发动机凸轮轴后端盖密封失效分析及优化

针对某型发动机开发试验中出现的凸轮轴后端盖密封失效问题，应用非线性有限元软件ABAQUS对后端盖、密封垫以及缸盖组成的整体系统进行了数值模拟，得到厂后端盖的变形和密封垫的压力分布。试验结果表明。导致密封失效的主要原因是后端盖刚度设计过低．对后端盖进行了结构优化，并进行了仿真和试验验证。结果表明，经优化后的凸轮轴后端盖能满足密封要求。     

铁通昆明城域传送网建设及优化思路浅析

对昆明城域传送网的建网原则、网络结构进行了介绍，对目前存在的问题进行了分析。并针对存在的问题提出了网络优化方向。     

基于多代理机制的列车运行调整模型及算法动态集成研究

分析列车运行调整问题研究的现状与进展,主要集中在模型研究和算法研究两个方面。分析传统求解模型及算法研究的局限性,提出对现有模型及算法进行动态集成的研究思路。采用基于多代理机制的动态集成方法,将模型对象和算法对象转化成多个代理,定义多代理之间的交互策略,实现调整方法的动态集成。提出基于多代理机制的列车运行调整问题模型及算法的动态集成系统。     

铁谱技术在监测施工机械运转工况中的应用

铁谱技术是对设备运行状态进行监测的新技术.根据施工机械的使用条件和故障特点,应用铁谱技术对施工机械运行工况进行监测,能准确地反映机械的磨损情况,获取故障信息,避免盲目拆卸,为开展对策性维修提供科学依据.