基于最大相关准则图像分割的结构化道路路径识别和跟踪算法

为提高基于视觉导航的智能车辆对结构化道路车道标识线的识别和跟踪精度,同时消除车流、阴影和光照不均匀等不利因素的影响,提出一种基于最大相关准则的图像分割算法及基于感兴趣区域的车道标识线跟踪算法:首先,对图像进行滤波和光线补偿等前期处理,采用最大相关准则的图像分割算法对道路图像进行阈值分割;然后,根据车道的结构特征及先验知识提取车道标识线的特征点,并运用最小二乘法对特征点拟合,得到车道模型的参数;最后,通过建立感兴趣区域(ROI)的方法实现对车道标识线的准确跟踪。试验结果表明,该算法具有很好的准确性、实时性和鲁棒性。     

基于激光扫描的智能车辆前方地形三维可视化技术研究

基于激光扫描仪的数据分析,对智能车辆前方地形数据的三维可视化技术进行了研究。首先对采集的离散数据进行预处理：采用中值滤波算法减弱噪声的影响,通过车体坐标系到世界坐标系的转换实现车辆行走过程中不同场景的拼接;然后基于Splatting理论,选取椭圆高斯足印函数实现了离散三维数据的直接体绘制;最后结合可视化工具包VTK（Visualization Toolkit）的连续数据场轮廓提取和交互操作功能,在Visual C＋＋开发环境下实现了基于激光扫描的环境信息可视化技术,可以达到逼真重构真实环境的可视化效果。     

基于定性和定量分析法的综合运输及运输管理关键标准研究

运用定性和定量相结合的方法研究智能运输系统(ITS)中综合运输及运输管理关键标准。具体如下:在目前的综合运输及运输管理标准体系表中,对一部分显而易见的标准先用定性的方法分析其是否为关键标准,得出第一部分关键标准。然后对剩下的标准运用层次分析法和聚类分析法相结合的方法,得出第二部分关键标准,即先用层次分析法得出各专家的权重向量表,对所有的权重向量表进行聚类分析,得出综合权重向量,按照综合权重向量确定第二部分关键标准。最后,合并两部分得出综合运输及运输管理关键标准。     

An ontological model to support communications of situation-aware vehicles

In an Intelligent Transport System (ITS) environment, the communication component is of great importance to support interactions between vehicles and roadside infrastructure. Previous studies have focused on the physical capability and capacity of the communication technologies, but the equally important development of suitable and efficient semantic content for transmission received notably less attention. Ontology is one promising approach for context modelling in ubiquitous computing environments, and in the transport domain it can be used both for context modelling and semantic contents for vehicular communications. This paper explores the development of an ontological model implementing relative geo-semantic information messages to support vehicle-to-vehicle communications. The proposed ontology model contains classes, objects, their properties/relations as well as some functions and query templates to represent and update the information of dynamic vehicles, inter-vehicle interactions and behaviour. This model was developed through a scenario enabling the evaluation of traffic conflict resolution approaches, by implementing a set of decision-making processes for intelligent vehicles. Given the scope of the proposed ontology modelling, it shows how vehicular communications can be used to update each vehicle’s context model. This work can be easily extended for more complex interactions among vehicles and the infrastructure.     

智能交通国际发展概况和国内优先考虑的课题

综述智能交通系统10年来在国际上的发展状况,讨论了我国研究开发智能交通系统的优先链。指出：在宏观上,我国应首先制定发展智能交通系统的战略规划以及相应的技术标准体系,以保证智能交通系统的兼容性、扩展性和互联性。并建议在我国及早成立智能交通协调机构,认为在我国优先发展的智能交通项目应首先考虑解决城市交通堵塞问题。     

Efficiency measurement in public transport: Are findings specification sensitive?

The need to measure transit system performance along with its various dimensions such as efficiency and effectiveness has led to the development of a wide array of approaches and vast literature. However, depending upon the specific approach used to examine performance, different conclusions are oftentimes reached. Using data from 15 European transit systems for a ten year time period (1990-2000), this paper discusses three important transit performance questions; (i) Do different efficiency assessment methodologies produce similar results? (ii) How are the two basic dimensions of transit performance, namely efficiency and effectiveness, related? and (iii) Are findings regarding organizational regimes (public operations, contracting and so on) sensitive to the methodological specifications employed? Results clearly indicate that efficiency scores and associated recommendations are sensitive to the models used, while efficiency and effectiveness are - albeit weakly - negatively related; these two findings can have far reaching policy implications.     

蒙西地区国际运煤通道研究

蒙古国的塔本陶勒盖煤田焦煤储量居世界第一位。通过分析甘其毛都口岸的功能定位和煤炭运量,为打通国际运煤通道,组成蒙西地区铁路运输网络,针对口岸发展提出规划建设蒙西地区国际运煤通道。并从通道构成及主要技术标准,以及运输组织、车流组织、列车编组、通过能力等方面,探讨运煤通道的运输组织模式。     

The provision of home to school transport in Northern Ireland

The provision of home to school transport is an important element of transport policy in local communities. This paper examines the provision of home to school transport in Northern Ireland. It reviews the nature of demand and provision, and the costs involved in providing the current system of home to school transport compared to other parts of the UK. In addition it also discusses issues surrounding the use of the statutory walking distance, safety on buses including the provision of ‘3 for 2’, standing on buses and seatbelts in Northern Ireland.     

关于秘鲁鱼粉自热自燃原因的探讨

近来，秘鲁鱼粉在远洋运输过程中屡次发生自然事故。本文就这一现象从鱼粉的组成、性质、抗氧剂的处理程度以及运输积裁条件加以分析，阐述了鱼粉发生自燃的诸多原因。并根据实际案例、秘鲁当地对鱼粉抗氧剂处理过程的现状及商检部门的检测方法等方面的资料分析，指出了秘鲁鱼粉在运输过程中发生自燃的主要原因是鱼粉中的抗氧剂分布不均匀，致使那些抗氧剂浓度不足的鱼粉在运输途中抗氧剂含量逐渐消耗而发生氧化反应，产生大量的氧化热，达到鱼粉的自燃点而发生自燃。