铁路货车转向架交叉杆焊接失效分析

针对交叉杆出现的疲劳断裂,开展了扫描电镜及焊接工艺试验验证分析,得到了由于焊偏引起的未熔合是造成交叉杆疲劳断裂的主要原因.同时,通过工艺试验,提出了进一步优化焊接接头设计,减小根部间隙更容易得到熔合良好的焊接接头的建议.     

浅水中浮式栈桥单浮箱系泊系统及运动响应特性

基于三维势流理论,利用水动力分析软件AQWA对浅水中浮式栈桥单浮箱系泊系统及运动响应进行研究。对初步设计的多种系泊系统进行优选,并计算浮箱在最优系泊系统下的运动响应幅值算子RAO。结果表明:聚酯缆材料极易疲劳破坏,浅水中交叉型半张紧式锚链系泊表现出良好的系泊性能。浮箱的振幅响应算子RAO与波浪周期变化及波浪作用方向有不可分割的关系,当波浪入射角为120°~150°时,浮箱的纵荡及纵摇RAO较大。为保证较小的垂荡值,浮箱布置可沿入射波方向。为保证较小的首摇角,浮箱布置应避免与来浪呈120°的入射角。     

基于STM32的蓄电池检测系统设计

蓄电池检测系统是蓄电池质量指标中非常重要的一环,直接影响蓄电池的性能和寿命。本文介绍一种以STM32微处理器STM32F103RCT6为核心的铅酸蓄电池高精度智能检测系统,可以同时检测电压、温度、液位,并根据神经网络计算得到电解液密度,用户在上位机完成测试参数设置,自动对电池的各项数据进行存储和报警。文中详细介绍了系统组成、硬件和软件设计。实践证明该检测系统满足实际需求。     

清管器在输油管道中的运动规律研究

在分析清管物理模型的基础上,建立了清管器前段塞流动的特征参数计算模型、动态数学模型以及相应的数值计算方法,并进行了数值模拟。利用数学模拟方法可以计算清管过程中管线的压力分布,利用压力分布可以跟踪清管球在管线内的运行,这为混输管路的运行管理提供了理论依据。     

Modeling the interactions between car and bicycle in heterogeneous traffic

In this paper, a new cellular automata model is proposed to simulate the car and bicycle heterogeneous traffic on urban road. To capture the complex interactions between these two types of vehicles, a novel occupancy rule is adopted in the proposed model to consider the variable lateral distances of mixed vehicular traffic. Based on massive simulations, microscopic fundamental diagrams under different bicycle densities are devised. With these, the bicycle's spilling behavior is then investigated and discussed. In order to reflect the interference of a bicycle on a car, the interference transformation from friction state to block state is modeled explicitly. Finally, different simulation results under different occupancy rules indicate that the constant and fixed occupancy rule adopted in the previous studies might lead to overestimation of car flux in the heterogeneous traffic flows with different bicycle densities. Copyright © 2013 John Wiley & Sons, Ltd.     

The identification and empirical characterization of vehicular (Lagrangian) fundamental diagrams in multilane traffic flow

Traditional macroscopic traffic flow modeling framework adopts the spatial–temporal coordinate system to analyze traffic flow dynamics. With such modeling and analysis paradigm, complications arise for traffic flow data collected from mobile sensors such as probe vehicles equipped with mobile phones, Bluetooth, and Global Positioning System devices. The vehicle‐based measurement technologies call for new modeling thoughts that address the unique features of moving measurements and explore their full potential. In this paper, we look into the concept of vehicular fundamental diagram (VFD) and discuss its engineering implications. VFD corresponds to a conventional fundamental diagram (FD) in the kinematic wave (KW) theory that adopts space–time coordinates. Similar to the regular FD in the KW theory, VFD encapsulates all traffic flow dynamics. In this paper, to demonstrate the full potential of VFD in interpreting multilane traffic flow dynamics, we generalize the classical Edie's formula and propose a direct approach of reconstructing VFD from traffic measurements in the vehicular coordinates. A smoothing algorithm is proposed to effectively reduce the nonphysical fluctuation of traffic states calculated from multilane vehicle trajectories. As an example, we apply the proposed methodology to explore the next‐generation simulation datasets and identify the existence and forms of shock waves in different coordinate systems. Our findings provide empirical justifications and further insight for the Lagrangian traffic flow theory and models when applied in practice. Copyright © 2015 John Wiley & Sons, Ltd.     

三辊轴式水泥混凝土振动摊辅滚平机

三辊轴式水泥混凝土振动摊铺滚平机是一种用于公路、桥面、机场跑道、室内外地面等铺筑工程的新型机械，文章对这种新机型的工作原理、结构特点、总体布置以及参数选择等进行了较为详细地介绍。     

高速公路对自然资源的消耗研究

从土地资源的占用和能源消耗两方面将高速公路与其他运输方式对自然资源的占用情况进行比较,并通过总结和分析我国高速公路的现状,得出高速公路较其他运输方式能更有效地利用自然资源,是资源集约型的交通运输方式。     

负荷对柴油机微粒排放特性及其组分的影响

分析了柴油机排气微粒 (PM)的组分及其生成机理 ,并通过试验研究了负荷对PM的排放特性及其组分的影响 ,指出了负荷与PM流量之间的指数函数关系以及PM中可溶性组分 (SOF)和不可溶性组分 (IOF)的含量随负荷的变化趋势     

基于实例推理的齿轮快速设计CAD系统研究

介绍了齿轮快速设计CAD系统的组成及软件实现，并用实例说明，本系统能快速、高效地进行齿轮设计。