An ontology-based framework to support performance monitoring in public transport systems

Managers of public transport systems have been facing for years the strategic challenge of maintaining high quality of transport services to improve the mobility of citizens, while reducing costs and ensuring safety and low environmental impact. A well-established way to evaluate the performance achieved by the system or by specific activities is to monitor Key Performance Indicators (KPI). However, existing management systems, which refer to flexible yet large and complex data models, provide a limited support to define and select relevant KPIs for the objectives at hand, and even the identification of whether and how the data model is capable to achieve a certain informative need is a critical and time-consuming task. This work is aimed to propose a framework to ease the development of a monitoring system in the public transport domain. The approach is based on the ontological representation of all the knowledge regarding indicators and their formulas, business objectives, dimension analysis and their relation with the Transmodel, the European reference data model for public transport information systems. On its top, a reasoning framework provides logic functionalities to interactively support designers in a set of common design tasks: the choice of the most suitable indicators for the performance monitoring needs at hand, the definition of new indicators and the identification of the minimal set of Transmodel modules needed to calculate them. A case study is included to discuss these applications, while an evaluation shows the feasibility of the approach.     

呼和浩特市优先发展城市公共交通探讨

通过对呼和浩特市城市公共交通现状的分析,指出呼和浩特市公共交通存在的问题,进一步说明保证呼和浩特市公共交通优先发展在缓减交通压力、提高城市公共客运效益、环境保护方面的重要意义,同时提出呼和浩特市优先发展公共交通应采取的措施.     

The effects of planned and unplanned transfers on public transport users' perception of transfer routes

Many authorities are investing in new infrastructure to improve the quality of public transport (PT) services in the hope to increase mode switch from cars. The goal is to provide users with an integrated multimodal PT network by facilitating transfers. There exists a lack in the clarity of the attributes which defines a planned transfer and the effects of planned transfers on users' willingness to use routes with transfers. The present study provides approximate effects of ‘planned’ and ‘unplanned’ transfers on PT users' decisions to use transfer routes. The study focuses on two attributes of ‘planned’ transfers, integrated physical connection of transfers and information integration. A user preference survey was undertaken in Auckland, New Zealand. Analysis of the results shows that physical integration is more important than information integration for current PT users. Results also suggest that information integration has a greater influence on users of transfer services which are more closely aligned to being ‘unplanned’.     

Dynamic simulation of train–truck collision at level crossings

Trains crashing onto heavy road vehicles stuck across rail tracks are more likely occurrences at level crossings due to ongoing increase in the registration of heavy vehicles and these long heavy vehicles getting caught in traffic after partly crossing the boom gate; these incidents lead to significant financial losses and societal costs. This paper presents an investigation of the dynamic responses of trains under frontal collision on road trucks obliquely stuck on rail tracks at level crossings. This study builds a nonlinear three-dimensional multi-body dynamic model of a passenger train colliding with an obliquely stuck road truck on a ballasted track. The model is first benchmarked against several train dynamics packages and its predictions of the dynamic response and derailment potential are shown rational. A geometry-based derailment assessment criterion is applied to evaluate the derailment behaviour of the frontal obliquely impacted trains under different conditions. Sensitivities of several key influencing parameters, such as the train impact speed, the truck mass, the friction at truck tyres, the train–truck impact angle, the contact friction at the collision zone, the wheel/rail friction and the train suspension are reported.     

城市轨道交通客运服务标准编制研究

城市轨道交通客运服务标准应主要针对乘客的需求而制定,是当前需要优先制定的服务业标准之一。通过对城市轨道交通客运服务及特性进行分析,结合国际相关服务标准以及我国现行的服务标准及标准化模式,提出了“以人为本”、系统性和与国际接轨的标准编制原则。乘客乘车是一个按时间顺序的活动过程,沿乘客乘车时间次序展开服务次序,是标准编制的重要技术方法。确定城市轨道交通客运服务内容是城市轨道交通客运服务标准编制的一项主要任务。在借鉴国外先进服务标准理念的基础上,通过轨道交通客运服务质量和从乘客实际需求出发来规范服务内容。最后,对乘客相应权益的规定做了说明。     

百色市农村客运站经营管理实践

农村客运站场网络是公路客运站场网络的重要组成部分,是发展农村客运、促进农村地区经济社会发展和城乡商品交流的重要平台.文章结合当前百色市农村客运站经营管理现状,分析经营管理中存在的问题,提出了相关的对策和措施.为规范当地农村客运市场秩序、加快农村客运网络建设、提高社会主义新农村建设水平提供参考.     

超级电容渡船——城市内河交通新构想

提出了一种将超级电容与渡船相结合的构想,通过对超级电容的特性和渡船航行特点的介绍,诠释了超级电容渡船的内涵,并在这个基础上对其可行性及实用性进行了分析,具有一定的参考价值。     

也论柴油轿车在国内市场的发展前景

研究了世界范围内柴油机在乘用车领域内的应用现状,阐述了柴油机作为车用动力的优势。根据国内的政策环境与市场环境,分析了排放法规、柴油品质对市场的影响。根据对柴油轿车的性能要求,包括振动和噪声、排放等,分析了更适合我国轿车柴油机发展的技术路线,并重点对若干关键技术和难点进行了剖析。柴油机技术进步和市场化应用表明,柴油轿车在我国具有广阔的应用前景,政府和企业应做好政策和技术上的准备。     

�ҹ���������ؼ��ڵ㰲ȫ�����о�

海上运输关键节点安全评价研究是保障我国海上运输通道安全的重要环节,为科学全面评价我国海上运输关键节点的安全状况,本文建立评价指标体系,引入投影寻踪方法构建安全评价模型,通过遗传算法求解,对关键节点的安全状况进行评价,并挖掘相关海峡的主要安全威胁。评价结果表明,涉及我国重要物资如石油、集装箱运输的霍尔木兹海峡、马六甲海峡、曼德海峡及苏伊士运河的安全水平相对较低,而且印尼地区的龙目海峡、巽他海峡及望加锡海峡的安全状况也相对较差。评价结果为我国制定保障海上运输安全措施及做出相关管理决策提供科学依据,对提高我国海上运输安全性与可靠性具有重要意义。