Specific object re-identification across non-overlapping camera views in traffic accidents

ABSTRACT

To improve the robustness of object re-identification in complex outdoor environments for traffic safety systems, a novel object re-identification algorithm based on the Individual Similarity Difference Feature (ISDF) method is proposed. This method can provide reliable support for specific object tracking during traffic accidents in video surveillance networks. First, all the images in the gallery are divided into three parts according to a segmentation ratio, and six types of feature for each part are extracted. Second, prototypes for each feature of the three parts are constructed. Third, the image sequence of the same person is grouped, and then the ISDF is extracted from each image. Finally, we use the AdaBoost classifier to judge whether the two objects are matched and then output the final results. Extensive experiments are conducted on two public data sets (Eidgenössische Technische Hochschule Zürich and multi-camera object tracking). The performance of the object re-identification method is superior to the latest methods.     

Time to burn: Flight delay,terminal efficiency,and fuel consumption in the National Airspace System

Improved Air Traffic Management (ATM) leading to reduced en route and gate delay, greater predictability in flight planning, and reduced terminal inefficiencies has a role to play in reducing aviation fuel consumption. Air navigation service providers are working to quantify this role to help prioritize and justify ATM modernization efforts. In the following study we analyze actual flight-level fuel consumption data reported by a major U.S. based airline to study the possible fuel savings from ATM improvements that allow flights to better adhere to their planned trajectories both en route and in the terminal area. To do so we isolate the contribution of airborne delay, departure delay, excess planned flight time, and terminal area inefficiencies on fuel consumption using econometric techniques. The model results indicate that, for two commonly operated aircraft types, the system-wide averages of flight fuel consumption attributed to ATM delay and terminal inefficiencies are 1.0–1.5% and 1.5–4.5%, respectively. We quantify the fuel impact of predicted delay to be 10–20% that of unanticipated delay, reinforcing the role of flight plan predictability in reducing fuel consumption. We rank terminal areas by quantifying a Terminal Inefficiency metric based on the variation in terminal area fuel consumed across flights. Our results help prioritize ATM modernization investments by quantifying the trade-offs in planned and unplanned delays and identifying terminal areas with high potential for improvement.     

An integrated traffic-driving simulation framework: Design,implementation, and validation

This paper first describes the process of integrating two distinct transportation simulation platforms, Traffic Simulation models and Driving Simulators, so as to broaden the range of applications for which either type of simulator is applicable. To integrate the two distinct simulation platforms, several technical challenges needed to be overcome including reconciling differences in update frequency, coordinate systems, and the fidelity levels of the vehicle dynamics models and graphical rendering requirements of the two simulators. Following the successful integration, the integrated simulator was validated by having several human subjects drive a 2.5 mile long segment of a signalized arterial in both the virtual environment of the integrated simulator, and in the real-world during the evening “rush hour”. Several aspects of driving behavior were then compared between the human subjects’ driving in the “virtual” and the real world. The comparisons revealed generally similar behavior, in terms of average corridor-level travel time, deceleration/acceleration patterns, lane-changing behavior, as well as energy consumption and emissions production. The paper concludes by suggesting possible extensions of the developed prototype which the researchers are currently pursuing, including integration with a computer networking simulator, to facilitate Connected Vehicle (CV) and Vehicle Ad-hoc Network (VANET) related studies, and a multiple participant component that allows several human drivers to interact simultaneously within the integrated simulator.     

Traffic consolidation in East Asian container ports: A network flow analysis

The proliferation of hub-and-spoke operations in maritime container transportation has resulted in the widespread consolidation of traffic flows. Utilising liner shipping network configurations, this paper assesses the impact of freight traffic consolidation in the container port industry by exploring the spatial pattern of traffic flow movements and identifying the variety of roles that container ports play within this context. On the basis of the network concept, the spatial inequality of freight traffic consolidation is determined by the density and direction of all meaningful connections (i.e. significant flows) identified by applying Multiple Linkage Analysis (MLA) to an initial traffic flow matrix.The effectiveness of the chosen methodology is tested empirically using a sample comprising the 18 major container ports in East Asia, together with another 21 important container ports located on the East–West trading route. Based on this sample network, the spatial structure of traffic flow consolidation reveals the nature and structure of hub-and-spoke operations within a port system, the relative hub-dependence of ports, the variety of roles which individual ports play within the overall structure of inter-port interactions and the hierarchical configuration of the port industry structure. The paper concludes that MLA offers new insights into the distributional inequality of traffic flows, the spatial and economic interactions between ports and the extent to which hinterlands overlap. Furthermore, the analysis clearly shows that inter-port relationships can no longer be evaluated as isolated phenomena; any change in a specific port’s competitiveness will directly impact upon the structure of the whole maritime transportation system. Port authorities and terminal operators will need, therefore, to carefully analyse and disentangle specific inter-port relationships in order to provide the most appropriate basis for their decision making.     

Experimental Economics and choice in transportation: Incentives and context

This paper reviews the preconditions for successful applications of Experimental Economics methods to research on transportation problems, as new transportation and research technologies emerge. We argue that the application of properly designed incentives, the hallmark of Experimental Economics, provides a high degree of experimental control, leading to internal validity and incentive compatibility. Both of these are essential for ensuring that findings generalize to contexts outside the immediate application. New technologies, such as virtual reality simulators, can generate external validity for the experiments by providing realistic contexts. GPS and other tracking technologies, as well as smart phones, smart cards and connected vehicle technologies can allow detailed observations on actions and real-time interactions with drivers in field experiments. Proper application of these new technologies in research requires an understanding of how to maintain a high level of internal validity and incentive compatibility as external validity is increased. In this review of past applications of Experimental Economics to transportation we focus on their success in achieving external and internal validity.     

中山市公共自行车出行特征调查分析

中山市2011年10月实施公共自行车租赁系统以来运营状况良好,笔者简要介绍了该系统的站点布局及运营模式,并通过大量的运营数据和问卷调查,分析了公共自行车使用者人群特征、租用次数与出行目的、单次公共自行车租用时间与步行到租车点耗时情况、周日与周末租借量的差异、租借量与天气的关系、公共自行车出行空间分布特征、出行者使用感受等基本特征,为其他城市开展此类规划建设提供参考。     

对船舶号灯、号型条款中常见误解类型的剖析

号灯、号型是船舶不可或缺的组成部分,是识别和判断船舶类型、大小、动态和工作性质的主要手段.尽管《1972年国际海上避碰规则》规定了各种船舶在不同动态下应显示的号灯或号型,但是由于船舶吨位增大,地方和港口主管机关对号灯、号型另行规定以及为满足当前操纵需要而设计的新型船舶出现,加大了对号灯、号型所提供的信息判断难度。本文以事故案例为引导,根据当前航行环境特点,对号灯、号型的规定进行有针对性的分析和研究。     

提高交通建设安全生产监督水平的途径研究

通过对当前交通基础设施建设市场现状、从业人员组成和特点、安全生产管理存在的问题等方面进行分析,提出提高安全生产监督管理水平的途径。     

Congestion pricing for Latin America: Prospects and constraints

In an effort to reduce the adverse impacts of the car and promote sustainable transport in Latin America, some governments have either implemented travel demand management policies or have considered ways of directly reducing the number of vehicles in congested areas. While demand management measures have been promoted in a small number of countries, including vehicular restrictions as well as the promotion of public transport modes, there are currently no congestion pricing programmes in operation in Latin America. This paper begins with an overview of travel demand management, including its principal aims as well as its primary objectives within the Latin American context. It discusses past efforts to promote traffic restraint and perspectives for developing congestion pricing schemes in both São Paulo and Santiago. Finally, it examines the potential role of congestion pricing as a demand management tool. While it is one of the most effective demand management measures in the industrialised world, a number of barriers currently prevent it from being widely adopted in Latin America.