基于改进型蚁群算法的车辆导航路径规划研究

在分析车辆路径规划问题(VLD)特点的基础上,提出了VLD的数学模型以及适用于求解VLD的蚁群算法。详细分析了蚁群算法的参数对算法收敛速度和计算结果精确度的影响,提出了一种能够提高算法的收敛速度和全局搜索能力的参数自适应调整的策略,并对原有基本蚁群算法进行了改进。随后进行了仿真试验,根据所得仿真结果将改进蚁群算法与基本蚁群算法从全局收敛能力、计算稳定性以及计算速度等方面进行了全面比较,结论表明改进蚁群算法各方面均优于基本蚁群算法,证明了改进算法的可行性及有效性。     

自适应路径规划系统研究

针对目前的路径规划系统普遍采用距离最短或时间最少等单一指标,不能自动识别驾驶员路径选择习惯,为驾驶员自适应地提供符合驾驶员偏好的诱导路径的问题,设计了自适应路径规划系统的框架,提出了一种基于驾驶员路径选择偏好的自适应路径规划算法。算法中设计了基于驾驶员路径选择偏好的多目标路阻函数、基于主成分分析和加权评分分析的评价指标确定方法以及驾驶员路径选择偏好权重的确定方法。最后,利用Mapx、VisualC＋＋和Access数据库联合开发出了自适应路径规划系统,并用长春市驾驶员的实例数据验证了系统的有效性和算法模型的正确性。     

感应线圈信号曲线的处理方法及其在车型识别中的应用

为提高车型识别的准确率,提出信号处理的方法：首先采用快速小波变换抽取原始曲线的近似轮廓,从而削弱了噪声等细节信息的干扰,并实现2^n倍的数据压缩;其次利用五点三次滤波器对上一步获得的近似曲线进行平滑,使得离散信号更接近于真实的连续信号;在此基础上提出基于峰值时间差的强鲁棒性车长检测方法;最后,根据形态匹配的要求,采用Akima插值法进行信号尺度的归一化处理。车型识别试验采用观测点的实测数据,并将结果与其他文献进行比较,说明所提出的方法的有效性。     

Influence of 3D printing on transport: a theory and experts judgment based conceptual model

Consumer 3D printing is on the rise and has the potential to significantly change the transport and logistics sector. Current literature on 3D printing and transport studies does not provide a systematic model of the impact of 3D printing on transport and related (policy relevant) areas, such as traffic safety, location decisions, accessibility and environmental effects. Based on a literature review and two rounds of expert consultation, we propose and refine a conceptual model as a way to approach this gap in the literature. The expert consultation yields that the conceptual model comprises the relevant and important elements for assessing the impact of 3D printing on transport and transport-related challenges. Location, needs and transport resistance are important: (a) city-level hubs are the most likely locations for 3D printers because they can coordinate material flows and gather expertise; (b) mass-individualisation and personification dictates the needs for 3D printers; (c) distribution networks will be organised more efficiently, less empty vehicles, but raw materials still need shipping. However, experts’ opinions diverged on the impact of 3D printing on transport volumes and environmental impacts.     

基于SHEL模型的客滚运输人为因素风险研究

根据客滚运输人为因素复杂、模糊的特点,文中在SHEL理论框架下,对客滚运输人为因素进行了分析研究。一改以往将客滚运输人为因素风险系统分为人、机、环境、管理四个子系统的做法,从人的因素、人-人界面因素、人-硬件界面因素、人-环境界面因素、人-软件界面因素五个方面进行了风险研究,并提出相应的决策建议。     

呼和浩特市客运出租汽车数量预测模型研究

一个城市的客运出租市场是否需要投放出租汽车和投放数量的多少,不仅影响服务质量,也影响每位出租汽车经营者的自身利益,从而影响整个．出租汽车行业的稳定与健康发展。本文对出租汽车影响较大的因素进行了统计和相关性分析,确定了自变量,采用回归模型和曲线拟合的方法建立了未来年份的出租汽车数量预测模型,预测结果和往年历史数据对比表明,时间变量的一元线性模型和实际值较接近;幂函数曲线的预测值增加较快,就呼和浩特市的具体情况,幂函数曲线的预测效果较好。本文给出了适合呼和浩特市区的出租汽车发展趋势和合理的数量预测。     

广州市公共交通一体化发展策略研究

居民出行的多样化,要求建设一体化的公共交通系统。首先介绍了城市交通一体化和公共交通一体化内涵,分析了广州市公共交通发展存在的问题,最后在此基础上提出了广州市公共交通一体化发展策略。公共交通一体化对于合理利用公共资源、有效调配运力运量、提高运输综合效率具有重大意义。     

河谷型城市公交线网特征与规划

本文针对我国河谷型城市在现有公交线网规划中存在的诸多问题,从河谷型城市的定义与特征入手,分析了河谷型城市公交线网的特征和存在的问题,就河谷型城市公交起讫点和换乘枢纽的设置进行了研究,阐述了几种相应的布局模式各自的优缺点及适应条件。通过对河谷型城市所具备特点的综合分析,并结合现有的交通方式,提出了适合我国河谷型城市公共交通发展的规划模式,从多方面对河谷型城市公共交通规划提出了改进意见,对河谷型城市公交线网规划具有一定的指导作用。     

Assessment of large transport infrastructure projects: The CBA-DK model

This paper presents a newly developed decision support model to assess transport infrastructure projects: CBA-DK. The model combines use of conventional cost–benefit analysis to produce aggregated single point estimates, with quantitative risk analysis using Monte Carlo simulation to produce interval results. The embedded uncertainties within traditional CBA such as ex-ante based investment costs and travel time savings are of particular concern. The paper investigates these two impacts in terms of the Optimism Bias principle which is used to take account of the underestimation of construction costs and the overestimation of travel time savings. The CBA-DK methodological approach has been used to apply suitable probability distribution functions on the uncertain parameters, thus resulting in feasibility risk assessment moving from point to interval results. The proposed assessment model makes use of both deterministic and stochastic based information. Decision support as illustrated in this paper aims to provide assistance in the development and ultimately the choice of action, while accounting for the uncertainties surrounding transport appraisal schemes. The modelling framework is illustrated by the use of a case study appraising airport and runway alternatives in the capital of Greenland – Nuuk. The case study has been conducted in cooperation with the Home Rule Authorities of Greenland.     

北京就业与交通时空变动及计量关系研究

文章结合北京就业的时空变动特征以及对道路交通需求的变化特征,从区域要素角度考察城市交通和就业的关系。通过构建就业交通需求与交通供给量之间的计量关系模型,进行时间序列关系研究和横截面关系研究,分析得到北京市就业与交通道路建设之间的关系。