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171.
Augmented Reality “AR” is a promising paradigm that can offer users with real-time, high-quality visualization of a wide variety of information. In AR, virtual objects are added to the real-world view in real time. The AR technology can offer a very realistic environment for enhancing drivers’ performance on the road and testing drivers’ ability to react to different road design and traffic operations scenarios. This can be achieved by adding virtual objects (people, vehicles, hazards, and other objects) to the normal view while driving an actual vehicle in a real environment. This paper explores a new Augmented Reality Vehicle “ARV” system and attempts to apply this new concept to a selected traffic engineering application namely the left-turn maneuver at two-way stop-controlled “TWSC” intersection. This TWSC intersection experiment, in addition to testing the feasibility of the application, tries to quantify the size of gaps accepted by different driver’s characteristics (age and gender). The ARV system can be installed in any vehicle where the driver can see the surrounding environment through a Head Mounted Display “HMD” and virtual objects are generated through a computer and added to the scene. These different environments are generated using a well defined set of scenarios. The results from this study supported the feasibility and validity of the proposed ARV system and they showed promise for this system to be used in the field-testing for the safety and operation aspects of transportation research. Results of the left-turn maneuver study revealed that participants accepted gaps in the range of 4.0-9.0 s. This finding implies that all gaps below 4 s are rejected and all gaps above 9 s are likely to be accepted. The mean value of the left-turn time was 4.67 s which is a little bit higher than reported values in the literature (4.0-4.3 s). Older drivers were found to select larger gaps to make left turns than younger drivers. The conservative driving attitude of older drivers indicates the potential presence of reduced driving ability of elderly. Drivers’ characteristics (age and gender) did not significantly affect the left-turn time. Based on the survey questions that were handed to participants, most participants indicated good level of comfort with none or small level of risk while driving the vehicle with the ARV system. None of the participants felt any kind of motion sickness and the participants’ answers indicated a good visibility and realism of the scene with overall good system fidelity.  相似文献   
172.
This paper introduces toxic air pollutants into the measurement of trucking productivity to obtain true productivity growth. Our results show that omitting or ignoring toxic air pollutants in measuring trucking productivity yields statistically significant biased productivity estimates in for 2002-2005. Trucking productivity growth was understated by the traditional productivity measure, because the latter did not account for reductions in truck air pollution over time. We also find that the difference between traditional and environmental efficiency scores was negligible, suggesting that environmental constraint did not distort efficiency in the trucking sector.  相似文献   
173.
文章针对目前全国治理公路车辆超载超限信息管理系统的现状,从全国联网的角度分析系统的需求、组网方案、数据存储与传输等关键问题,着重阐述了系统建设中的多业务大数据量的SAN数据存储和流媒体QOS控制方法,为完善全国联网治超系统的建设提供参考。  相似文献   
174.
交通运输是国家节能减排工作的重点领域,为促进交通运输节能减排技术发展,开展交通运输节能减排示范项目是政府部门一项重要的政策措施。对示范项目进行绩效评价工作能衡量财政资金投入政策实施效果,也是交通运输主管部门非常关注的问题。在交通运输节能减排示范项目绩效评价的逻辑框架下,运用层次分析法建立交通运输节能减排示范项目绩效评价指标体系及权重值,具有较好的实操性,能为开展同类型项目的绩效评价工作提供参考。  相似文献   
175.
目前,自动驾驶技术在乘用车领域已获得突破性发展;为提高通行效率和出行安全起到了极大的作用。自动驾驶技术在商用车领域的应用,有望较好解决高昂的人力成本和难以提高的效率等问题。然而,目前自动驾驶技术在货车的应用大多采用跟乘用车同样的标准进行规范,这在实际应用中存在着诸多的问题;例如,在FCW和AEB功能中货车在相同车速的制动距离要远大于乘用车,而其所采用标准规定的碰撞预警时间却并无多大不同,这在实际场景中存在着较大的安全隐患[1,2]。此外,货车质量和体积较大,且较多应用于长途运输,运输过程中会经历包括高温、严寒、山区等多种复杂气候场景,这些都将对货车自动驾驶技术在车辆制动效能、能耗以及多场景应用等方面提出更有针对性规范的要求。本文针对货车的应用场景特点,为其自动驾驶技术应用标准化提出了建议。  相似文献   
176.
公路环境保护管理工作是国家环境保护工作的重要组成部分,也是绿色交通建设和运营的重要组成内容。文章分析了绿色交通发展新形势下,公路行业环境保护的新形势和新要求,从强化组织管理、注重源头控制、加强过程控制、注重资源节约和集约利用、增强绿色环保科技支撑能力等方面提出发展思路。  相似文献   
177.
针对杭锦旗气田高液气比气井井间串接集气距离长、管道压损大的问题,文中用权重法估算了影响管道气液混输距离的因素,表明管道直径是影响集气距离的最重要因素,权重比约56.1%。根据杭锦旗气田气井生产参数,对不同采气管道规格串接模式进行了研究,确定了适用于不同集气量和串接井数的采气管道规格系列,提出了直线式与辐射式相结合的井间串接模式,为杭锦旗气田地面集输站场和管网设计提供技术依据。  相似文献   
178.
A predominant observation in Hong Kong is the continuous loss in ferry patronage. There are two main reasons for this: poor level-of-service and better competitors. New roads, bridges, and tunnels are serving the buses, and to some extent the railways; whereas the investment in ferry terminals is relatively at a lower level. On the one hand, there is no need to promote the ferries in a free market environment; but on the other hand, the ferries have the best safety record, can only relieve some traffic congestion and need water access that is one of the characteristics of Hong Kong. The goal of this paper is to design a planning approach combined with an evaluation procedure on how to make the best use of the existing water and pier resources in Hong Kong through the provision of commercially viable ferry services. The approach used covers the impact of future developments planning up to 2006 comprising all public transport modes in Hong Kong (heavy rail, metro, bus, and ferry). The planning tool is based on a newly developed multi-objective evaluation method in order to assess the ferry routes with scientific, practical, and simplified analyses for future use. This assessment is applied to the existing ferry routes and candidate routes and can also be carried out on an individual route basis or on a given set of routes. The objective functions set forth analytically in the evaluation method take into account the interests of the three participants: the passengers, the operators and the government. The proposed ferry network design formulation and the suggested new ferry routes will have a positive impact on changing the ferry system’s image in Hong Kong.  相似文献   
179.
This paper explains the theory in support of total cost analysis (TCA) to compare transportation system alternatives. The full costs of each alternative are first aggregated, including travel time costs and monetizable environmental and social costs. Many costs which are considered on the benefits side of the equation in benefit-cost analysis (BCA) as "cost savings" are brought over to the costs side. Total cost differences among alternatives are then traded off against their estimated non-monetized benefits or impacts, just as a consumer trades off product quality against cost before deciding which product he or she will buy. One advantage of TCA over traditional BCA is that the concept of "total cost" is more easily understood by the public and by political decision-makers than BCA concepts such as "net present worth", "benefit-cost ratio" and "internal rate of return". A second advantage is that there is no suggestion that all "benefits" have been considered; decision-makers are free to use their own value judgements to trade off total cost against non-monetizable social, environmental and economic impacts, just as they trade off quality and convenience against cost when purchasing goods and services in their roles as consumers. The TCA approach is demonstrated in this paper through a case study of two systemwide alternatives for the Baltimore, MD urban area.  相似文献   
180.
全国交通运输科技大会全面回顾总结了"十一五"交通运输科技工作,研究分析交通运输科技发展面临的新形势、新要求,部署"十二五"科技工作。文章基于交通运输科技大会的部署与要求,介绍了"十一五"交通运输科技工作取得的成绩与经验,分析了"十二五"交通运输科技发展的总体思路和重点任务,提出了做好"十二五"交通运输科技工作的具体要求。  相似文献   
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