A new methodology for incident detection and characterization on surface streets

In this paper, a new methodology is presented for real-time detection and characterization of incidents on surface streets. The proposed automatic incident detection approach is capable of detecting incidents promptly as well as characterizing incidents in terms of time-varying lane-changing fractions and queue lengths in blocked lanes, lanes blocked due to incidents, and incident duration. The architecture of the proposed incident detection approach consists of three sequential procedures: (1) Symptom Identification for identification of incident symptoms, (2) Signal Processing for real-time prediction of incident-related lane traffic characteristics and (3) Pattern Recognition for incident recognition. Lane traffic counts and occupancy are the only two major types of input data, which can be readily collected from point detectors. The primary techniques utilized in this paper include: (1) a discrete-time, nonlinear, stochastic system with boundary constraints to predict real-time lane-changing fractions and queue lengths and (2) a pattern-recognition-based algorithm employing modified sequential probability ratio tests (MSPRT) to detect incidents. Off-line tests based on simulated as well as video-based real data were conducted to assess the performance of the proposed algorithm. The test results have indicated the feasibility of achieving real-time incident detection using the proposed methodology.     

Robust optimization for the correlated MIMO downlink with imperfect channel state information

To reduce the performance deterioration induced by imperfect channel state information (CSI) in cor-related multiple input multiple output(MIMO) downlink, the linear transmit/receive filters should be optimized to be robust to imperfect CSI. A sub-optimization algorithm based on minimizing sum MSE conditional on available imperfect CSI estimates subject to a per-user power constraint is proposed. The algorithm adapts the existing MMSE algorithm from uncorrelated single-user MIMO system with perfect CSI to correlated MIMO downlink with imperfect CSI. Simulation shows that the suboptimal algorithm can effectively mitigate the performance loss induced by imperfect CSI and has a good convergence performance. In addition, the effect of spatial correlation on the performance of the proposed algorithm is also simulated.     

西安地铁2号线车辆乘客信息系统

文章从车辆乘客信息系统的系统构成、功能和特点等方面对西安地铁2号线车辆乘客信息系统进行了详细描述,表明该系统有良好的动态性能和控制性能。     

产品结构树在CAPP信息管理中的应用

通过对CAPP系统信息管理的分析，论述了在实用化CAPP系统中建立产品结构树的必要性，提出了一种线性产品结构树的数学模型以基于该数学模型在VC＋＋6．0下实现产品树的方法－采用一个可变长度的一维数组描述产品树节点，标识各节点在产品结构树中的层次关系。用该方法表示产品结构树，产品结构逻辑关系清晰，数据冗余小，简化了建立产品树的过程，是一种简单有效的方法。     

海事信息安全关键技术研究

因全国海事系统的计算机都通过网络联系到一起,信息安全的内涵也就发生了根本的变化。它不仅从一般性的防卫变成了一种非常普通的防范,而且还从一种专门的领域变成了无处不在。当步入21世纪这一信息社会、网络社会的时候,建立起一套完整的海事信息安全体系也成为当务之急。     

信息诱导系统在高速公路的应用

结合实际施工,对当前环城高速公路交通压力提出改善途径,通过整合资源为广大司乘人员的出行提供更好的服务。     

LED可变信息标志的维护

介绍了LED可变信息标志系统如何实现维护,在高速公路上使用的LED可变信息标志出现故障时,及时有效地得到修复,从而达到降低维护费用的目的。     

铁路客运段信息化综合管理系统

根据我国铁路客运段的现状,集成基于GSM-R的无线移动售/补票子系统、车长办公子系统、餐车管理子系统、列车GPS定位与自动语音播报子系统、列车移动视频监控子系统五大车载系统,构建客运段信息化综合管理系统。在客运段建立集成平台,统一数据接口,规范客运业务,提供WEB查询服务,并对其中的两个关键子系统给出实现方案。铁路客运段信息化综合管理系统已在武汉铁路局下属客运段实际运行,取得了良好效果。     

潜艇大气环境多传感器信息融合技术研究

介绍多传感器信息融合技术的概念,分析了多传感器集成与信息融合的问题,介绍了贝叶斯准则、D-S证据理论、模糊理论和神经网络的4种方法与算法,论述了潜艇大气环境多传感器信息融合技术研究的优点及其必要性.     

Multimodal,multiclass stochastic dynamic traffic assignment for evaluating information provision strategies

A multimodal, multiclass stochastic dynamic traffic assignment model was developed to evaluate pre‐trip and enroute travel information provision strategies. Three different information strategies were examined: user optimum [UO], system optimum [SO] and mixed optimum [MO]. These information provision strategies were analyzed based on the levels of traffic congestion and market penetration rate for the information equipment. Only two modes, bus and car, were used for evaluating and calculating the modal split ratio. Several scenarios were analyzed using day‐to‐day and within day dynamic models. From the results analyzed, it was found that when a traffic manager provides information for drivers using the UO strategy and drivers follow the provided information absolutely, the total travel time may increases over the case with no information. Such worsening occurs when drivers switch their routes and face traffic congestion on the alternative route. This phenomenon is the 'Braess Paradox'.