考虑时空相关性的固定检测缺失数据重构算法

应用相关性理论, 研究了交通流数据中缺失值与其他数据的相关性, 对与缺失值不同相关性的数据给予不同的权重值, 提出了基于交通流时空相关权重的重构算法, 并以北京市二环快速路为研究对象, 运用VISSIM仿真软件建立仿真模型, 利用仿真数据对新算法和现有算法进行了对比分析。研究结果表明: 在连续缺失1~10个数据时, 模型1的重构值与仿真值平均相对误差最大仅为1.8766%, 一般情况下, 平均相对误差均在1.0000%以下, 可见, 模型1算法优于现有的重构算法。     

Innovative detector layout for automated traffic turning volume counting

Because of many advantages, loop detectors are the most common practice for obtaining data to control intersections. However, they have some drawbacks, including the fact that multiple detectors are usually required to monitor a location. The current practice in many cities is to install four consecutive loop detectors per lane, or two at the stop bar and one as an advanced detector. In some cities, there are also departure detectors. All these configurations have some practical problems and do not produce accurate counts especially in shared lanes. In this paper, a new placement configuration for departure detectors is proposed and named the mid‐intersection detector (MID). In this configuration, departure detectors are moved back to the middle of the intersection in such a way that they can be activated by more than one movement at different times. In some cases, departure detectors lack equations for calculating turning movements, a problem solved by MIDs because each movement passes more detectors along its path (without increasing the number of loops), and therefore they can produce more accurate and reliable data for obtaining turning movement counts. Copyright © 2017 John Wiley & Sons, Ltd.     

车辆点火高压检测器的设计与试制

利用电磁感应原理，设计和试制车辆点火高压检测器。该检测器能将汽油机正常运转时点火系高电压的变化转化为感生电动势，驱动发光二极管发亮，从而确定汽油机点火系是否工作正常。具有简单易携带的优点。     

高速公路网络最小检测器布设新方法

对节点和路段进行定义，探索节点数目与路段数目之间的数量关系。根据流量守恒原则，建立了一个包含 n +1个方程、3n -m 个变量的齐次线性方程组。通过对方程组的系数矩阵进行初等行变换，直到找到一个最大无关向量组。将无关组向量对应的变量命名为基变量，其余变量命名为非基变量，所得到的基变量总可用非基变量表示。因变量与路段一一对应，只要在非基变量所对应的路段布设检测器，就可确定整个网络中所有路段的流量。对最小检测器布设数目的存在性和唯一性进行了证明，给出了任意网络检测器布设率的通用公式。应用该方法，设计了贵阳市区部分高速公路网络的最小检测器布设方案。     

导弹轨上运动参数测量系统设计与应用

为了在导弹发射的强烈冲击振动和高温环境下得出导弹在发射导轨上的运动规律,介绍了采用光电探测、数字存储测试（黑匣子）技术结合基于VC平台下的数据处理方法来获取导弹在发射筒中运动的时间、位移、速度和加速度等数据,实现了导弹发射试验中轨上运动参数的精确测量,保证了导弹内弹道分析的试验数据需要。     

A simple algorithm for the estimation of road traffic space mean speeds from data available to most management centres

The control of the evolution of road traffic streams is highly related to productivity, safety, sustainability and, even, comfort. Although, nowadays, the findings from research efforts and the development of new technologies enable accurate traffic forecasts in almost any conditions, these calculations are usually limited by the data and the equipment available. Most traffic management centres depend on the data provided, at best, by double-loop detectors. These loops supply time means over different aggregation periods, which are indiscriminately used as the bases for subsequent estimations. Since space mean speeds are those needed in most applications (note the fundamental relationship between flow and density in traffic flow theory), most current practice begins with an error. This paper introduces a simple algorithm that the allows estimation of space mean speeds from the data provided by the loops without the need for any additional financial outlay, as long as the traffic in each time interval of aggregation is stationary and its speed distribution is log-normal. Specifically, it is focused on the calculation of the variance of the speeds with regard to the time mean, thus making possible to use the relationship between time mean speeds and space mean speeds defined by Rakha (2005). The results obtained with real data show that the algorithm behaves well if the calculation conditions help fulfil the initial hypotheses. The primary difficulties arise with transient traffic and, in this case, other specific methodologies should be used. Data fusion seems promising in this regard. Nevertheless, it cannot be denied that the improvement provided by the algorithm turns out to be highly beneficial both when used alone in the case of stationarity or as a part of a fusion.     

JM-A型密贴检查器与ZYJ7型电液转辙机电路连接的分析

主要针对当道岔上同时安装JM-A型密贴检查器与ZYJ7型电液转辙机时,根据两者的动作原理,对其之间表示电路的连接进行分析.     

红外线阵探测器驱动电路的低噪声设计

论文首先介绍了红外线阵探测器的系统组成和各个组成部分的功能,详细分析了红外探测系统的噪声来源,并结合实际经验,从软件到硬件电路设计,总结了降低噪声的方法,最后通过分析实验数据,得出红外线阵探测系统输出信号的噪声均方差（RMS）等于0．68mV,计算得到中波线阵探测器的NETD等于80ink,长波红外探测器的NETD等于40mK。实验数据显示通过采用本文低噪声的设计,驱动采集电路达到了比较低的噪声值,红外焦平面探测系统总体成像性能达到理想效果。     

国外沥青混凝土路面新型研究方法分析

介绍国外沥青混凝土路面新型研究方法,并着重介绍了运用这些研究方法取得的最新研究成果。这些研究方法和成果,可为国内沥青混凝土路面科研、设计和施工提供借鉴。     

基于行程时间估计的快速路检测器布设密度优化方法研究

随着智能交通运输系统对道路实时交通信息的迫切需求,布设高密度、全方位的交通检测器已成为共识,但是高密度的检测器布设带来的是硬件投资的急剧增加,因此有必要进行检测器布设密度的优化。利用快速路行程时间估计方法分析了检测器布设密度优化问题,认为从行程时间估计误差和合理投资的角度出发,检测器布设并不是密度越大效果越好,而是存在一个合理范围,该范围可以指导工程中实际检测器数目的选择。