基于Trans Modeler的城市快速路交通设计方案的微观仿真评价

基于Trans Modeler仿真平台对北京市通惠河北路开前后两个方案进行了评价分析,详细阐述了Trans Modeler仿真平台下交通微观仿真的技术路线、方案设计以及OD反推技术的实现和输出指标的分析方法,对新开通的城市快速路的分担率进行了量化评估,并给出了评价结论。     

Flow—shop网络作业计划模型的解法

将Flow-Shop网络作业计划的优化模型Sch(m,n)Lp^[1]化为向量矩阵线性空间，利用线性空间的理论提出了一个求解Flow-Shop网络最优作业计划模型的有效解法。     

多跨充液管道的振动特性分析

考虑管道与液体之间的泊松耦合与结合部耦合,推导了低频情况下的充液直管轴向、横向振动传递矩阵与刚性支撑的点距阵.使用传递矩阵法计算两种边界条件下单跨和多跨充液管道的模态频率及模态振型.结果表明,在充液管道振动分析中,流固耦合作用不能忽略,多跨管道系统由于刚性支撑的加入使系统频率增加.     

Modelling and characteristic analysis of tri-axle trucks with hydraulically interconnected suspensions

In this paper, a new hydraulically interconnected suspension (HIS) system is proposed for the implementation of a resistance control for the pitch and bounce modes of tri-axle heavy trucks. A lumped-mass half-truck model is established using the free-body diagram method. The equations of motion of a mechanical and hydraulic coupled system are developed by incorporating the hydraulic strut forces into the mechanical subsystem as externally applied forces. The transfer matrix method (TMM) is used to evaluate the impedance matrix of the hydraulic subsystem consisting of models of fluid pipes, damper valves, accumulators, and three-way junctions. The TMM is further applied to find the quantitative relationships between the hydraulic strut forces and boundary flow of the mechanical–fluid interactive subsystem. The modal analysis method is employed to perform the vibration analysis between the trucks with the conventional suspension and the proposed HIS. Comparison analysis focuses on free vibration with identified eigenvalues and eigenvectors, isolation vibration capacity, and force vibration in terms of the power spectrum density responses. The obtained results show the effectiveness of the proposed HIS system in reducing the pitch motion of sprung mass and simultaneously maintaining the ride comfort. The pitch stiffness is increased while the bounce stiffness is slightly softened. The peak values of sprung mass and wheel hop motions are greatly reduced, and the vibration decay rate of sprung mass is also significantly increased.     

基于OD反推模型预测客运通道客流量

OD矩阵是进行客流预测的重要基础数据,在实际操作过程中,获取吸引区之间的OD矩阵却是非常困难的,一般采用OD调查的方式,但缺陷是调查过程较为费时、费力。本文提出一种免OD调查,利用客流区段观测值直接反推OD矩阵的方法。首先讨论了传统"四阶段"模式与OD反推预测模式的联系和区别,然后阐述以重力模型为结构的基于区段客流量反推OD矩阵模型,并利用最大似然法对模型参数进行迭代求解,最后结合一个具体实例,运用该方法对武广客运通道的客流量进行了预测分析,采用试算法模拟重力模型的参数,误差控制良好,结果验证了方法的有效性。     

星形曲折延边三角形接线平衡变压器的阻抗匹配与数学模型

从基本方程组出发,分析了星形曲折延边三角形接线平衡变压器的运行特性.根据理想平衡变压器的技术条件给出了星形曲折延边三角形接线平衡变压器的通用阻抗匹配关系,扩展了阻抗匹配空间,证明以前得到的结果只是阻抗匹配空间的子集,增大了产品设计自由度.给出了变压器一次侧与二次侧间电气量变换关系和相坐标下的节点导纳矩阵,为进行牵引供电系统有关问题的分析计算奠定了基础.同时,从电气特性表达式上揭示了星形曲折延边三角形接线、星形延边三角形接线、星形三角形接线变压器之间的演化关系.     

基于状态矩阵的铁路枢纽列流图编制方法

针对铁路枢纽网络结构复杂、列流图绘制工作难度大的特点，研究铁路枢纽列流图的自动编制算法. 根据铁路枢纽内车站连接方向多，列流线在站内交错衔接疏解困难的特点，为车站接入点引入状态矩阵，利用状态变量记录列流线在车站区域的分布状态. 以列车类型作为一级排序，相同类型按列流径路从长到短的次序铺画列流线，借助指示线段实现列流量的标注. 采用所提算法开发了枢纽列流图编制软件，基于枢纽网络图和列车流矩阵，通过人机交互定义车站及连接线布局，实现列流线的快速编制与信息标注. 通过实例证明了算法的有效性和可行性.     

Analysis of the flexural vibration of ship’s tail shaft by transfer matrix method

A ship＇s tail shaft has serious flexural vibration due to the cantilevered nature of the propeller＇s blades. Analysis of the nature frequency of flexural vibration is vital to be able to provide effective shock absorption for a ship＇s tail shaft. A mathematic model of tail shaft flexural vibrations was built using the transfer matrix method. The nature frequency of flexural vibration for an electrically propelled ship＇s tail shaft was then analyzed, and an effective method for calculating it was proposed： a genetic algorithm （GA）, which calculates the nature frequency of vibration of a system. Sample calculations, with comparisons by the Prohl method under conditions bearing isotropic support, showed this method to be practical. It should have significant impact on engineering design theory.     

大规模铁路运量分布研究

探讨了大规模铁路运量分布研究中的几个问题：分布模型的选择、数据的预处理及在对某些品类货物预测时稀疏矩阵的赋值等。分析及实际计算表明，改进后的增长系数模型和物理类比模型较适合于大规模铁路区域ＯＤ流分布预测；对预测运量数据进行数值分解和迭加，可以较好地处理计划性数据，从而提高预测精度；预先对大规模稀疏ＯＤ矩阵零元素赋微量值，从计算的角度看可行，但是也掩盖了局域网络的实际不平衡。