A disaggregate analysis of factors influencing port selection

In this paper are presented the results of a multinomial logit model used to explain the selection of a port for each shipment exported from the US in December 1999. The model is estimated for combined shipments, and one model is estimated for each of four commodity types (bulk, foods, fabrics, manufactured). Results are compared across commodities to find the significance of the distance in either direction, the frequency of sailings, and the average size of vessels sailing along a route. Results of the estimation do not match those that would be expected. Potential reasons are given for such variations, along with numerous methods by which the modelling could be improved. Methods for improvement suggested include structuring of the model to represent more accurately the competitive scenario of each port, constraining the choice set for each shipments from characteristics of the carrier, and the commodity.     

Potential safety benefits of lane departure prevention technology

Motor vehicles with advanced safety technologies are rapidly entering the marketplace and the impact of new features are transforming safety on roadways. Among the several safety related technologies currently available in the market, this paper aims to forecast the reduction in crashes with gradual adoption of vehicles with lane departure prevention (LDP) technology. Crash data for the state of Alabama from 2014 to 2016 were used to evaluate the safety benefits of LDP technology. In Alabama, 75% of single-vehicle crashes are the result of lane departure. A 20% effective LDP system implies, whereby an LDP system would prevent a vehicle from exiting a roadway on 20% of applicable instances, would reduce 2.7% and 16.4% of the relevant single-vehicle lane departure (SVLD) crashes by 2020 and 2045 respectively. With increase in the effectiveness of the technology, a greater reduction in crashes was observed. With 100% effectiveness, this technology can prevent 66.5% of SVLD crashes by year 2045. This study presents the first estimations of the number of crashes that could be reduced using LDP and therefore could have significant impacts on public and industry adoption rates of the technology. The results of this study influence policy making and regulatory approaches to improving motor vehicle safety and further recommend education and outreach activities to increase awareness on the benefits of LDP technology.     

Estimating multimodal transit ridership with a varying fare structure

This paper studies public transport demand by estimating a system of equations for multimodal transit systems where different modes may act competitively or cooperatively. Using data from Athens, Greece, we explicitly correct for higher-order serial correlation in the error terms and investigate two, largely overlooked, questions in the transit literature; first, whether a varying fare structure in a multimodal transit system affects demand and, second, what the determinants of ticket versus travelcard sales may be. Model estimation results suggest that the effect of fare type on ridership levels in a multimodal system varies by mode and by relative ticket to travelcard prices. Further, regardless of competition or cooperation between modes, fare increases will have limited effects on ridership, but the magnitude of these effects does depend on the relative ticket to travelcard prices. Finally, incorrectly assuming serial independence for the error terms during model estimation could yield upward or downward biased parameters and hence result in incorrect inferences and policy recommendations.     

智能网联汽车协同生态驾驶策略综述

为了跟踪近年来智能网联汽车(CAV)协同生态驾驶策略的研究进展, 分析了车辆、驾驶行为、交通网络和社会这4类因素对CAV能耗的影响程度, 以车辆、基础设施和旅行者为对象对目前CAV生态研究进行分类, 重点分析了信号交叉口生态驶入与离开、生态协同自适应巡航控制、匝道合流区生态协同驾驶、生态协同换道轨迹规划和生态路由5种典型车辆协同生态驾驶应用场景的研究现状。分析结果表明: 相比人类驾驶方式, 在任何交通流量CAV 100%渗透率的条件下和低交通流量CAV部分渗透率的条件下, CAV油耗节省效果显著, 最高可达63%, 而具有部分智能化和网联化等级的CAV油耗可至少节省7%;现有研究较少考虑人机共驾情况下, 驾驶人反应延迟和自动控制器传输延迟导致的轨迹跟踪偏离; 现有研究将车车通信/车路通信假定为理想数据交互过程, 未考虑通信拓扑、传输时延、通信失效与基站切换等因素对CAV生态协同驾驶策略的影响; 现有研究较少探讨多车道、交叉口转向-直行共用车道和U型车道等交通场景, 以及不同智能网联等级CAV与人类驾驶汽车、行人、自行车等共存的混合交通条件下的生态驾驶策略; 受限于自动驾驶技术和基础设施尚未成熟和完善, 真实交通场景下的测试验证工作尚未开展; 车辆控制、车车通信、多车协同、混合交通流场景、半实物仿真测试和真实交通场景测试等方面将是CAV协同生态驾驶策略的进一步发展方向。     

无线射频识别（RFID）一场战争

研究似乎表明无线射频识别硬件销售商正因损失重大而大伤元气，但一些零售商却有所获利，Matthew Flynn报道。[编者按]     

COUPE LIFE BRILLIANCE AUTO Zhonghua Coupe 18TAT

车能带给人们别样生活,而一台个性十足、完全不同于其他车款的Coupe,更将全然颠覆你的生活态度!对于尚未有车的人群来说,车是—个梦,而当美梦成真之时,亦揭开有车生活的序幕;同理,如果你够胆魄选择了一台Coupe作为你的座驾,恭喜你,你会拥有的不止是高频回头率、高调的心态,更将迎来以Coupe为核心的另类有车生活,而这种生活的真谛也许只有你,Coupe车主才有资格说三道四。     

A novel arterial travel time distribution estimation model and its application to energy/emissions estimation

Arterial travel time information is crucial to advanced traffic management systems and advanced traveler information systems. An effective way to represent this information is the estimation of travel time distribution. In this paper, we develop a modified Gaussian mixture model in order to estimate link travel time distributions along arterial with signalized intersections. The proposed model is applicable to traffic data from either fixed-location sensors or mobile sensors. The model performance is validated using real-world traffic data (more than 1,400 vehicles) collected by the wireless magnetic sensors and digital image recognition in the field. The proposed model shows high potential (i.e., the correction rate are above 0.9) to satisfactorily estimate travel time statistics and classify vehicle stop versus non-stop movements. In addition, the resultant movement classification application can significantly improve the estimation of traffic-related energy and emissions along arterial.