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61.
针对部分路段不能获取完整交通信息的问题,提出使用无人机对未布设固定型交通信息检测器路段进行交通巡视,完善交通信息。通过时空网络建立了一个总飞行时间最短、最大单机飞行时间最短的多目标模型,确定最佳的无人机数量和交通信息收集路径。新模型不仅利用时空网络技术细致刻画了无人机在巡视过程中的飞行轨迹,而且加入了对未布设固定型交通检测器路段的巡视次数以及巡视时间间隔约束问题,使巡视路径更加合理。情景分析表明,使用两架无人机进行巡视时,总飞行时间最短为37min,在23min 内完成巡视任务;随着最大单机飞行时间权重的增大,无人机的总飞行时间增加9.76%,最大单机飞行时间减少8.70%。算例分析表明,所建模型和方法能够解决大规模路网的多无人机调度问题,能够根据实际需求得到满意的巡视路径。 相似文献
62.
城市轨道交通系统供电制式与受流方式分析 总被引:1,自引:1,他引:0
朱俐琴 《电力机车与城轨车辆》2003,26(3):29-31
对城市轨道交通系统的供电制式与受流方式的技术经济性能进行了系统分析,提出了大中城市修建地铁和轻轨可采用的受流方式,为城市轨道交通系统选择供电制式与受流方式提供了参考和建议。 相似文献
63.
Collecting microscopic pedestrian behavior and characteristics data is important for optimizing the design of pedestrian facilities for safety, efficiency, and comfortability. This paper provides a framework for the automated classification of pedestrian attributes such as age and gender based on information extracted from their walking gait behavior. The framework extends earlier work on the automated analysis of gait parameters to include analysis of the gait acceleration data which can enable the quantification of the variability, rhythmic pattern and stability of pedestrian’s gait. In this framework, computer vision techniques are used for the automatic detection and tracking of pedestrians in an open environment resulting in pedestrian trajectories and the speed and acceleration dynamic profiles. A collection of gait features are then derived from those dynamic profiles and used for the classification of pedestrian attributes. The gait features include conventional gait parameters such as gait length and frequency and dynamic parameters related to gait variations and stability measures. Two different techniques are used for the classification: a supervised k-Nearest Neighbors (k-NN) algorithm and a newly developed semi-supervised spectral clustering. The classification framework is demonstrated with two case studies from Vancouver, British Columbia and Oakland, California. The results show the superiority of features sets including gait variations and stability measures over features relying only on conventional gait parameters. For gender, correct classification rates (CCR) of 80% and 94% were achieved for the Vancouver and Oakland case studies, respectively. The classification accuracy for gender was higher in the Oakland case which only considered pedestrians walking alone. Pedestrian age classification resulted in a CCR of 90% for the Oakland case study. 相似文献
64.
Travel time functions specify the relationship between the travel time on a road and the volume of traffic on the road. Until recently, the parameters of travel time functions were rarely estimated in practice; however, a compelling case can be made for the empirical examination of these functions. This paper reviews, and qualitatively evaluates, a range of options for developing a set of travel time functions. A hierarchy of travel time functions is defined based on four levels of network detail: area, corridor, route and link. This hierarchy is illustrated by considering the development of travel time functions for Adelaide. Alternative sources of data for estimating travel time functions are identified. In general, the costs and benefits increase as the travel time functions are estimated at finer levels of network detail. The costs of developing travel time functions include data acquisition costs and analysis costs. The benefits include the potential for reducing prediction errors, the degree of application flexibility and the policy sensitivity of the travel time functions. 相似文献
65.
The integration of internet and mobile phones has opened the door to a new wave of utilizing private vehicles as probes not only for performance evaluation but for traffic control as well, gradually replacing the role of traffic surveillance systems as the dominant source of traffic data. To prepare for such a paradigm shift, one needs to overcome some key institutional barriers, in particular, the privacy issue. A Highway Voting System (HVS) is proposed to address this issue in which drivers provide link- and/or path-based vehicle data to the traffic management system in the form of “votes” in order to receive favorable service from traffic control. The proposed HVS offers a platform that links data from individual vehicles directly with traffic control. In the system, traffic control responds to voting vehicles in a way similar to the current system responding to prioritized vehicles and providing the requested services accordingly. We show in the paper that the proposed “voting” system can effectively resolve the privacy issue which often hampers traffic engineers from getting detailed data from drivers. Strategies to entice drivers into “voting” so as to increase the market penetration level under all traffic conditions are discussed. Though the focus of the paper is on addressing the institutional issues associated with data acquisition from individual vehicles, other research topics associated with the proposed system are identified. Two examples are given to demonstrate the impact of the proposed system on algorithm development and traffic control. 相似文献
66.
Ehab I. Diab Ahmed M. El-Geneidy 《Transportation Research Part A: Policy and Practice》2012,46(3):614-625
Transit agencies implement many strategies in order to provide an attractive transportation service. This article aims to evaluate the impacts of implementing a combination of strategies, designed to improve the bus transit service, on running time and passenger satisfaction. These strategies include using smart card fare collection, introducing limited-stop bus service, implementing reserved bus lanes, using articulated buses, and implementing transit signal priority (TSP). This study uses stop-level data collected from the Société de transport de Montréal (STM)’s automatic vehicle location (AVL) and automatic passenger count (APC) systems, in Montréal, Canada. The combination of these strategies has lead to a 10.5% decline in running time along the limited stop service compared to the regular service. The regular route running time has increased by 1% on average compared to the initial time period. The study also shows that riders are generally satisfied with the service improvements. They tend to overestimate the savings associated with the implementation of this combination of strategies by 3.5-6.0 min and by 2.5-4.1 min for both the regular route and the limited stop service, respectively. This study helps transit planners and policy makers to better understand the effects of implementing a combination of strategies to improve running time and passenger’s perception of these changes in service. 相似文献
67.
简要分析了铁通城域网现状,提出城域网动力环监系统的建设原则,并针对采集、传输与组网技术以及后期的运用问题进行了分析与思考。 相似文献
68.
李旭芳 《武汉船舶职业技术学院学报》2006,5(6):50-54
《电子签名法》的实施,第一次明确了电子认证服务的市场准入制度和电子签名保密等相关规定,对解决电子商务、电子政务过程中产生的诚信度问题将起到积极作用。同时,《电子签名法》的实施,对税收征管工作产生了很大影响。文章阐述了《电子签名法》带来的相关影响,并提出了改进税收征管工作的措施。 相似文献
69.
洋山深水港集装箱“水水中转”集疏运模式与对策* 总被引:1,自引:0,他引:1
“水水中转”集疏运是港口集疏运体系中重要的组成部分。随着上海建设国际航运中心和东北亚枢纽港目标的提出,上海港口的可持续发展对洋山深水港“水水中转”的集输运能力提出了更高的要求。通过分析目前洋山深水港水水中转集疏运的现状,研究洋山深水港现有水水中转集疏运模式和存在的问题,试图研究通过相应对策来完善洋山深水港“水水中转”集疏运体系。 相似文献
70.
概括了公路路网管理的基本要求,提出了路网管理信息支持系统的概念,对系统功能进行了分析,设计了系统结构框架.所提出的路况与路网交通信息采集方案、系统三层架构、决策与调度机制、六大功能是全新的设想,具有前瞻意义和可操作性. 相似文献