分布式工业进程参数监测系统实时多任务软件的设计

作者从操作系统的观点出发,分析分布式工业过程参数监测系统实时多任务软件的方法,解决了在DOS环境下,支持多任务问题。     

浅析摩托车镀锌件三价铬彩色钝化工艺及质量控制

为提高摩托车镀锌件镀锌层的耐腐蚀性,增加装饰性,改善金属基体与镀层的结合力,通常要进行钝化处理.钝化工艺是镀锌的一个重要工艺,采用品质有保证的三价铬钝化剂是保证质量的前提条件,工艺过程质量控制是钝化的关键,膜厚度和耐腐蚀检测是钝化质量的保证.     

基于知识工程的道岔零部件设计

利用CATIA软件的知识工程进行道岔零部件的系列化设计,建立了企业的三维模型库,显著减少设计人员的重复工作量,提高设计的效率和质量。     

基于数字化技术的轴类零件圆度误差测量方法研究

轴类零件的圆度误差会影响零部件的使用寿命。针对以往测量法存在的不足,提出了一种基于数字化技术的轴类零件圆度误差测量方法。该方法采用数字化非接触式激光测量方式对轴类零件的轴端面、轴径面进行测量采集三维数据点;对轴端面数据点进行稳健平面拟合获取轴端面所在平面的平面特征值;将轴径面上数据点投影到轴端面所在平面上获取投影点;采用投影点和轴端面所在平面的平面方程求解几何圆方程,求取几何圆参数;根据投影点与几何圆参数从而求取轴类零件的圆度误差值。通过实验验证表明,该算法在对轴类零件的圆度测量方面具有较好的实用性且精度满足要求。     

A network option portfolio management framework for adaptive transportation planning

A real option portfolio management framework is proposed to make use of an adaptive network design problem developed using stochastic dynamic programming methodologies. The framework is extended from Smit’s and Trigeorgis’ option portfolio framework to incorporate network synergies. The adaptive planning framework is defined and tested on a case study with time series origin-destination demand data. Historically, OD time series data is costly to obtain, and there has not been much need for it because most transportation models use a single time-invariant estimate based on deterministic forecasting of demand. Despite the high cost and institutional barriers of obtaining abundant OD time series data, we illustrate how having higher fidelity data along with an adaptive planning framework can result in a number of improved management strategies. An insertion heuristic is adopted to run the lower bound adaptive network design problem for a coarse Iran network with 834 nodes, 1121 links, and 10 years of time series data for 71,795 OD pairs.     

Real time queue length estimation for signalized intersections using travel times from mobile sensors

We study how to estimate real time queue lengths at signalized intersections using intersection travel times collected from mobile traffic sensors. The estimation is based on the observation that critical pattern changes of intersection travel times or delays, such as the discontinuities (i.e., sudden and dramatic increases in travel times) and non-smoothness (i.e., changes of slopes of travel times), indicate signal timing or queue length changes. By detecting these critical points in intersection travel times or delays, the real time queue length can be re-constructed. We first introduce the concept of Queue Rear No-delay Arrival Time which is related to the non-smoothness of queuing delay patterns and queue length changes. We then show how measured intersection travel times from mobile sensors can be processed to generate sample vehicle queuing delays. Under the uniform arrival assumption, the queuing delays reduce linearly within a cycle. The delay pattern can be estimated by a linear fitting method using sample queuing delays. Queue Rear No-delay Arrival Time can then be obtained from the delay pattern, and be used to estimate the maximum and minimum queue lengths of a cycle, based on which the real-time queue length curve can also be constructed. The model and algorithm are tested in a field experiment and in simulation.     

城市轨道交通对房地产价值的影响研究——以武汉市轨道交通为例

城市轨道交通是一种快捷、高效、节能环保的大容量城市客运交通方式,而且对于沿线房地产的开发具有巨大的带动作用.本文定性分析了城市轨道交通对房地产价值的影响机理,并采用地价影响函数模型,对武汉城市轨道交通1号线地价影响函数相关参数进行了标定.定量研究证实了城市轨道交通时房地产价值的拉动作用.最后提出了武汉市轨道交通与房地产...     

路企直通运输在大窑湾港的运用

采用传统的铁路运输组织方法,铁路和港口间存在交接车手续复杂,机车等待时间长,路港信息交流不畅等问题.本文论述了路企直通运输方式在大窑湾港的运用,重点研究了运输组织流程再造、统一调度指挥、合署办公机制等优化措施.直通运输的实施,提高了港口和港前站的作业效率,实现了铁路和港口的双赢.     

长江下游安庆复式分汊河段整治关键部位研究

分汊型河道是冲积平原河流中的常见河型,分汊型河段与单一河段的最大不同是分汊型河段具有两汊或多汊过流,分流区和汇流区的水沙具有与单一河道不同的运动特点,并容易因分汊口门的放宽,水流分散,泥沙在此淤积造成水深不够,产生碍航问题。分汊河型又包括很多不同类型,其中对复式分汊型河段航道问题的研究较少,整治技术也不成熟。以长江安庆复式分汊河段为研究对象,采用河工模型试验研究与实测资料分析相结合的方法,在分析安庆河段水流运动规律的基础上,探讨了不同整治部位实施工程的效果,通过综合比较提出了安庆复式分汊河段的整治关键部位。     

冷再生技术在周口市106国道大修工程中的应用

周口市106国道大修工程的实践证明,采用先进的现场冷再生技术替代传统方法,能很好地解决原路段的病害,使其功能得到恢复、结构得到补强。而且该方案造价低,对交通干扰小,是一种很好的道路维修方案。