横风下高速列车系统动力学的平衡状态法

基于车辆-轨道耦合动力学和空气动力学提出了一种快速计算横风下高速列车系统动力学行为的平衡状态方法.首先,忽略轨道不平顺并利用流固耦合联合仿真方法计算横风下高速列车的平衡状态;然后,将平衡状态下的气动力加载到车辆-轨道耦合动力学模型并计算高速列车动力学响应.利用建立的平衡状态方法,研究了列车在速度为13.8 m/s的横风下以350 km/h速度运行时的流固耦合动力学行为.比较了平衡状态方法和联合仿真方法两种方法下列车姿态、安全性和舒适性指标的差异,计算结果差别在3.26%以内.研究结果表明:平衡状态方法计算横风下高速列车流固耦合的效率更高.     

基于BP神经网络的石化过程在线故障监测系统

针对石化生产过程的高危性,开发了石化过程在线故障监测系统.通过OPC(OLE for process control)接口从生产现场采集实时数据,采用BP神经网络(back-propagation artificial neural network,BPNN)的模式识别方法,对生产过程进行实时故障监测,及时发现故障工况并提示操作人员采取相应措施,以减小系统运行的风险.BP神经网络的训练数据来自历史数据库,用户根据已发生过的故障工况确定训练数据的时间范围.BP网络模型的各项参数根据多次试验得到.对某工段的10个故障,其故障诊断准确率达到90%以上,具有较高的实时性和准确性.     

弯管流量计的工程应用

简述了大口径烟气弯管流量计的工作原理,详细介绍了弯管流量计在贵溪冶炼厂精矿干燥系统中的工程应用情况及其特点。     

关于软件工程专业教育方案的探讨

本文提出了一个适合国内软件工程专业的教育方案,并给出了软件工程专业教学应该涵盖的基本内容和计划。     

污泥生物沥浸法深度脱水工程及其运行效果分析

无锡太湖新城污水处理厂一期污泥深度脱水工程处理规模约35 t/d(含水率80%),采用污泥生物沥浸法。介绍了生物沥浸法的工艺流程、反应系统组成、主要构筑物及设备参数,并列出2012年工程的实际运行效果。结果表明,生物沥浸法用于污泥深度脱水效果较好,处理后的泥饼可有效地进行资源化利用。     

Comparison of two suspension control strategies for multi-axle heavy truck

Two simple and effective control strategies for a multi-axle heavy truck, modified skyhook damping (MSD) control and proportional-integration-derivative (PID) control, were implemented into functional virtual prototype (FVP) model and compared in terms of road friendliness and ride comfort. A four-axle heavy truck-road coupling system model was established using FVP technology and validated through a ride comfort test. Then appropriate passive air suspensions were chosen to replace the rear tandem suspensions of the original truck model for preliminary optimization. The mechanical properties and time lag of dampers were taken into account in simulations of MSD and PID semi-active dampers implemented using MATLAB/Simulink. Through co-simulations with Adams and MATLAB, the effects of semi-active MSD and PID control were analyzed and compared, and control parameters which afforded the best comprehensive performance for each control strategy were chosen. Simulation results indicate that compared with the passive air suspension truck, semi-active MSD control improves both ride comfort and road-friendliness markedly, with optimization ratios of RMS vertical acceleration and RMS tyre force ranging from 10.1% to 44.8%. However, semi-active PID control only reduces vertical vibration of the driver’s seat by 11.1%, 11.1% and 10.9% on A, B and C level roads respectively. Both strategies are robust to the variation of road level.     

Selection model of trip time for rural population

Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nine grades were selected as the alternatives of trip time, the variables affecting time choice and the method getting their values were determined, and a multinomial logit (MNL) model was developed. Another 1 200 trip data of rural population were selected to testify the model’s validity. The result shows that the maximum absolute error of each period between calculated value and statistic is 3.6%, so MNL model has high calculation accuracy.     

提高化工原理实验教学质量的探索与实践

在化工原理实验教学中,以提高化工原理实验教学质量为目的,从实验教学内容及设备的更新、教学方法、实验预习和实验过程考核等几个方面对化工原理实验教学进行了探索与实践,取得了较满意的教学效果。     

通用计算机半实物仿真系统设计与实现

首先对各种制导控制武器系统的异同进行分析和比较。在此基础上提出一个面向制导控制武器系统的半实物仿真系统模型,介绍该系统的设计思想及实现步骤。     

公交专用道设置前后路段交通流模型的比较

通过对实际调查数据的分析，分别建立了路段上无公交专用道及设置不同形式的公交专用道条件下公交车与社会车辆的速度模型，并对比分析了车辆的运行状态和车速变化特征，为确定公交专用道的设置条件以及公交专用道的效益评价等提供技术支持和量化的参考依据．