高速公路中央分隔带槽形混凝土护栏的开发研究

简要介绍了高速公路中央分隔带槽形混凝土护栏的开发过程，提出了改进后的中央分隔带混凝土护栏的定型尺寸。研究结果表明，改进后护栏不仅造价降低，同时也改善了车辆碰撞的防护效果。     

基于键合图的车用蓄电池建模与仿真

按照键合图的规则,分别建立了蓄电池等效电路的键合图模型和冷却系统的键合图模型,然后将电系统和热系统耦合在一起,实现了蓄电池系统的键合图模型,最后建立了蓄电池的数学模型和仿真模型,并实现了动态仿真。     

Bus Priority Using pre-signals

The need to provide efficient public transport services in urban areas has led to the implementation of bus priority measures in many congested cities. Much interest has recently centred on priority at signal controlled junctions, including the concept of pre-signals, where traffic signals are installed at or near the end of a with-flow bus lane to provide buses with priority access to the downstream junction. Although a number of pre-signals have now been installed in the U.K., particularly in London, there has been very little published research into their design, operation and optimisation. This paper addresses these points through the development of analytical procedures which allow pre-implementation evaluation of specific categories of pre-signals. The paper initially sets out three categories of pre-signal, which have different operating characteristics, different requirements for signalling and different impacts on capacity and delay. Key issues concerning signalling arrangements for these categories are then discussed, together with a summary of the analytical approach adopted and the assumptions required. Equations are developed to allow appropriate signal timings to be calculated for pre-signalised intersections. Further equations are then developed to enable delays to priority and non-priority traffic, with and without pre-signals, to be estimated with delay being taken here as the key performance criterion. The paper concludes with three application examples illustrating how the equations are applied and the impacts of pre-signals in different situations.The analyses confirm the potential benefits of pre-signals, where these signals apply to non-priority traffic only. Where buses are also subject to a pre-signal, it is shown that disbenefits to buses can often occur, unless bus detectors are used to gain priority signalling.     

基于时频混合格式的桥梁抖振响应计算方法

利用一种时频混合格式计算桥梁在紊流风激励下的抖振时程响应。针对动力风荷载既有时域内定义的抖振激励力,又有用频域内的颤振导数来定义的与结构自身运动有关的气弹自激力,存在时频混合项的特点,引入时频混合格式的AFT方法来计算桥梁抖振时程响应;在保持频域计算高效性的同时,又通过拟力概念在时域计算结构非线性不平衡力和气弹力造成的振型耦合,通过迭代使其收敛。通过算例验证了该格式是一种可行的计算桥梁抖振响应的方法。     

UC/OS-Ⅱ在驼峰信号微机监测系统中的应用

根据驼峰信号微机监测采集数据实时性强的特点,在分析以往监测系统软件框架缺点的基础上,提出采用实时多任务操作系统UC/OS-Ⅱ,实现一个监测项对应一个采集任务的软件设计新思路,从而达到了简化程序编写,提高实时性,优化程序框架结构的目的.     

三峡库区某石拱危桥改造治理

分析了三峡库区某石拱桥出现问题的主要原因,提出了改造治理对策和改造治理方案,并对改造方法进行了总结.     

滑模摊铺机施工水泥混凝土路面经济性分析的探讨

通过对砼滑模摊铺机与人工小型机械施工砼路面的经济性进行比较,计算滑模摊铺机在不同里程施工时的最低台班进度,以及按8 a折旧推算其年生产规模和设备规费的提取额度.     

南昌生米大桥总体设计

生米大桥是南昌市外环快速道上的城市桥梁，全长3880m，简要介绍生米大桥的项目概况、建设条件、总体布局、技术标准、技术特点、关键技术、科学研究等有关情况。     

基于光电复合缆的水声信号采集发射传输系统

众所周知水下电磁环境复杂,在水下采用电缆传输电信号非常容易受到海洋电磁环境干扰,并且随着距离的增加,电信号受到干扰和衰减也就越大.因此水下中长距离的信号传输采用光电复合缆传输是一个比较好的选择,光纤用来传递水声信号,电缆用来传输电力.因此本文设计了一种基于光电复合缆的水声信号采集发射传输系统,能够很好地解决上述问题.本设计将要采集和发射的水声模拟信号在采集发射端和主机端转换成光信号,端到端之间的传输采用光信号,而采集发射端的供电则由光电复合缆的电缆提供.     

船舶撞击力作用下的墩式码头水工建筑物安全评估

针对遭受船舶撞击的码头水工建筑物安全评估问题，结合船舶与码头发生碰撞的实例，以码头结构现场检测结果为基础，采用水运、公路、铁路行业规范公式推算失控船舶的撞击力，计算船舶撞击后的码头水工建筑物稳定性，综合评估遭受船舶撞击的码头水工建筑物的安全性和适用性，并给出受损部位修复处理及后续运营期监测措施。结果表明，被碰撞的码头靠船墩结构安全性评估等级为A级，结构适用性评估等级为B级。该安全评估方法可为事故鉴定、受损结构修复和码头后期运营提供科学依据和技术支撑。