上海地铁综合无线分布系统的研究

从技术角度对地铁内综合无线分布系统进行多信号频率研究及干扰分析,通过对系统核心器件综合合路平台、高功率线性功放的研究,实现系统最佳覆盖效果,并通过地铁1、2号线GSM、CDMA覆盖工程实例得以验证。     

翻车机系统PLC584改造可行性方案分析

我港翻车机（简称C／D）系统的核心控制单元是MODICON公司的PLC584。经多年运转,其故障率高,工作稳定性、可靠性差,且技术已过时,需进行改造。MODICON公司生产的MODICON TSX QUANTUM是全系列兼容的工控PLC产品,其性能优越,功能强大,用它来升级改造C／D控制系统是解决现有诸多问题、扩展并优化系统性能的良好途径。     

Semirigid analysis of extended end plate connections based on correlation and sensitivity

Traditionally, semi-rigid analysis of extended end plate connections is assumed to be deterministic parameters. Most of the moment-rotation models of the joint are determined by curve-fitting and statistically regressed with the test data. Parameters of these models have little physical meaning, and the effect of correlations in the parameters is neglected. This paper deals with a semi-rigid joint of extended end plate connections based on correlation and sensitivity analysis. A numerical study was carried out and the finite element analysis was validated compared with the experimental results. The relative moment-rotation model was concluded based on correlations in parameters and probabilistic sentivity analysis. The relationship between height and width of steel beam was partial correlation. The relationship between thickness of steel beam flange and thickness of steel beam web was also partial correlation. Height and width of steel beam, and distance of upper bolts to axle wire of steel beam section were important sensitive parameters for the extended end plate connections.     

Improved scheme of internet congestion control under moving average filter

An important task of Internet congestion control is inhibiting sporadic data flow to maintain a suitable window size or route queue length. Such a requirement is just consistent with the basic idea and function of a moving average filter. In this paper one prior Internet congestion control model, named transmission control protocol (TCP)/random early detection (RED) stroboscopic model, is studied, and then one new scheme is proposed to enlarge its stable domain, where a simple moving average filter is introduced to inhibit sporadic data flow as possible. In the novel scheme the bifurcation phenomenon is postponed without any extra controller. The effectiveness of the new scheme is verified by theoretical analyses and numerical simulations.     

公路投资项目决策物元模型研究

以可拓学的物元模型和可拓集合、关联函数理论为基础,对公路投资决策进行研究.建立了公路投资项目决策物元模型.在现有相关研究的基础上,提出了公路投资项目决策的评价指标体系,并给出了各指标值范同、等级划分和权重确定方法.进行了实例分析,研究结果表明:该模型没计合理,符合实际,能较完整地反映公路投资项目的综合水平.     

北京市高峰勤务机制实施效果分析

以北京市交通管理实践为基础,以海量数据分析为依据,系统总结了高峰勤务的保障手段,对其运行效果进行了客观评估,深刻剖析其制约因素,并就如何破解存在的困难提出了意见以期为相关工作提供参考。     

船舶CAD/CFD一体化设计过程集成技术研究

传统的船型设计中,CFD大多用来检验CAD的设计结果,而不是用来驱动产品设计.两者基本上处于"孤岛"状态,没有实现有机的集成.为使CFD更好的服务于船舶总体设计,实现船舶CAD/CFD的一体化优化设计,需要针对现有的计算软件和设计模式,利用集成优化平台进行流程集成及数据集成.文中采用集成优化平台iSIGHT初步实现了船舶三维建模软件、CFD计算分析软件之间的数据集成和过程集成.     

基于KWP2000的信息采集系统的开发

针对目前汽车电子技术的快速发展和对车辆实现快速故障诊断的需求,设计并开发了基于KWP2000的车载信息采集系统。系统采用嵌入式ARM Cortex-M3芯片为控制单元,可实现发动机ECU与采集设备之间稳定可靠、快速的数据通信,实时采集车辆的速度、故障码等数据,便于故障诊断。     

隧道初期支护钢拱架早期承载性能试验研究

为系统分析隧道格栅钢架和型钢钢架支护初期的力学性能,针对三肢格栅钢架、四肢格栅钢架和14号工字型钢钢架开展室内加载试验研究;同时,引入钢材性能系数以直观比较不同类型钢架的综合性能。研究表明： 1）在支护初期,格栅钢架与混凝土的结合性能比型钢钢架好,并且在受到集中力影响时,型钢钢架的安全隐患大于格栅钢架; 2）钢拱架在实际使用中会受到偏心荷载的不利影响,其中四肢格栅钢架受到的影响最显著,设计时应增加四肢格栅钢架跨中抗扭钢筋布置。     

运行车辆燃料消耗影响因素分析

减少运行车辆燃料消耗是我国实现节能减排的一项重要内容,根据我国运行车辆燃料消耗的现状,分析影响燃料消耗的主观因素和客观因素,提出减少燃料消耗的措施,并对我国常用节油产品的节油率进行分析,对于道路运输业持续、稳定的发展具有重要意义。