某商用车驾驶室全浮式悬置系统开发

论述了某商用车驾驶室全浮式悬置系统结构设计及主要参数控制要点,提出了DMU运动分析校核、基于EXCEL的参数初始设计等设计手段,并运用有限元分析、动力学模拟等分析手段进行了优化,使该车较好的满足了可靠性和驾驶室振动舒适性要求,避免了后期大量的设计改进工作,从而缩短了产品开发周期并降低了产品研发成本.     

先进的铝屑回收生产线和工艺

摩托车整体式铸造铝合金车轮在进行切削加工时,切屑量约占车轮总质量的20%,最高达30%左右。因此,回收摩托车整体式铸造铝合金车轮机加工过程中的铝屑可降低生产成本,具有良好的经济效益。先进的铝屑回收生产线上所有设备的开动、运行和停止均能实现程序控制和实时监控,机械化、自动化水平较高。另外,铝屑不直接接触火焰,烧损率低。     

动静载荷试验法荷载-沉降曲线分析方法研究

为将准静荷载试验法中动态荷载-沉降曲线转换为静态荷载-沉降曲线,并尽量与工程实际相接近,对已有分析方法进行了适用性探讨和分析比较,在原有理论基础上提出了新的C模型分析方法,将整个试验过程中桩-土系统的阻尼系数按照理论前提随时间变化分为3段,各段分别计算,最后组合成随时间变化的阻尼系数曲线。然后根据单质点模型的平衡方程计算出静态P-S曲线。借助大型计算软件MATLAB,对具体工程实例分别采用已有方法与C模型法分别进行编程计算。计算结果表明:C模型法计算出的静态P-S曲线处于由卸载点法和起始刚度法得出的静态曲线之间,该方法能较合理地分析准静载荷试验法的荷载-沉降曲线。     

A Variable Time-Discretization Strategies-Based,Time-Dependent Shortest Path Algorithm for Dynamic Traffic Assignment

Within the simulation-based dynamic traffic assignment (SBDTA) model, the time-dependent shortest path (TDSP) algorithm plays a crucial role in the path-set update procedure by solving for the current optimal auxiliary solution (shortest path). Common types of TDSP algorithms require temporal discretization of link/node time/cost data, and the discretization could affect the solution quality of TDSP and of the overall SBDTA as well. This article introduces two variable time-discretization strategies applicable to TDSP algorithms. The strategies are aimed at determining the optimal time discretization for time-dependent links/nodes travel time data. The first proposed strategy produces a specific discretization interval for each link. The second proposed strategy generates time-varying intervals for the same link over the analysis period. The proposed strategies are implemented in a link-based time-dependent A* algorithm in a SBDTA model DynusT and tested with two numerical experiments on two traffic networks. The results show that the proposed discretization methods achieve the research goal—to flexibly and scalably balance the memory usage and run time for SBDTA without degrading the convergence. This property is rather important when dealing with a large real-world network with a long analysis period.     

基于乘客感受视角的城市轨道交通车站服务水平综合评价实证研究

以城市轨道交通车站为研究对象,立足于乘客自身感受,通过系统分析,构建了以快捷性、舒适性、安全性等为一级指标的城市轨道交通车站服务水平的评价指标体系。并以西安地铁钟楼车站为例,运用AHP确定指标权重并基于改进的TOPSIS对其进行评价,以验证指标体系和改进的TOPSIS方法在城市轨道交通车站服务水平综合评价中的可行性和可靠性。     

试论公路施工中软土地基处理技术的应用

当前我国的基础建设工程项目越来越多,项目施工中由于地质构造和地形条件的多样化,施工人员需要根据现场情况进行具体的施工,其中软土地基在公路施工中的处理是影响工程施工质量的重要因素之一。该文通过对软土地基特点的阐述,对公路施工中软土地基处理技术进行了分析和探讨,可供同行参考。     

路面结冰监测技术研究进展

路面结冰显著降低了路面抗滑能力,极易诱发交通事故.路面结冰自动监测和及时预警对于保障行车安全具有重要意义.结冰监测技术主要依靠各种类型的结冰传感器实现结冰的感知和预报.目前结冰传感器主要有光纤式、电学式、机械式、红外式等不同类型.对各种结冰监测技术进行了总结,并探讨了这些技术在道路工程中应用的可行性.     

考虑人体坐姿模型的汽车主动悬架最优控制

根据IS05982:2001 (E)推荐使用的人体坐姿低频振动模型,基于1/4汽车垂向振动模型,建立了车辆-人体振动系统的力学与数学模型.采用最优控制理论,设计了汽车主动悬架线性二次型调节控制器.在Matlab/Simulink环境下分别对被动悬架与主动悬架的性能进行仿真,时域和频域仿真结果对比表明,所建立的车辆-人体振动系统动力学模型能很好地反映人体振动特性,设计的主动悬架线性二次型调节控制器使汽车平顺性得到明显改善.     

Modeling and control strategy development of a parallel hybrid electric bus

This paper presents the system modeling, control strategy design, and experiment validation of a parallel hybrid electric bus with an automatic manual transmission (AMT) and a dry clutch. The mathematical model representation and the system architecture of the powertrain are first described. Next, a complete control scheme including energy management strategy and coordinated control of the AMT and the clutch is presented. The controller and powertrain models are then integrated in a way that the power management and the hybrid driveline perform in real world. The analysis and validation through model simulation and comparison with experiment data are conducted. A good agreement between the model and experiment demonstrates the efficacy and credibility of the integrated model. The integrated model is employed in both simulation and bench-test assessments for the development of a hybrid control unit. The results indicate that the model-based design methodology is beneficial to systematically analyzing and understanding the dynamics of hybrid electric powertrain.     

数据处理方法在路堤工后沉降预测中的应用

介绍了3种预测路堤工后沉降的模型及求解方法,并应用于工程实例中;把3种方法得到的结果与实测结果相比较,指出各种方法各有优点,各有其适用情况.