NSF/USDOT ICSST: Exploring New Traffic Characteristics and Performance Measures Using Feature Extraction and Texture Characterization of Spatiotemporal Traffic Contour Maps

信息和通信技术继续改善地面运输系统的运输数据获取和性能监测能力。目前，从全国交通管理中心(TMC)实时收集的海量数据中提取的信息很少。尽管交通数据收集技术取得了巨大进步，但没有同时努力通过最大限度地利用从存档和实时交通数据中提取信息的方法来改进现有的业绩衡量标准。当前的平均行程时间和延误的点估计形式的度量本质上是从一阶统计量导出的属性，并且不能充分揭示某些局部和系统范围的属性，例如光滑性、粗糙度、正则性、同质性、熵等。这些属性只能通过高级程序和二阶统计量来分解，这些程序和二阶统计量能够通过利用构建的时空交通等高线地图的时空相关性和纹理特征来表征交通操作的质量，这是一个类似于数字图像的纹理表征的概念。研究的主要目标是：(1)通过量化时空等值线地图的特殊特征来开发一类新的性能指标；(2)使用新的性能指标来研究过渡阶段的交通行为；(3)建立扩展高速公路路段的在线和离线性能评估程序；(4)调查新指标与事故频率和严重程度之间的相关性；(5)比较复发和非复发情况的纹理特征；以及(6)开发新措施的实施模块，由TMC实时执行。该项目审查时空高速公路交通等高线地图，以改进现有的高速公路性能衡量标准，并确定高速公路拥堵和撞车的前兆条件。将大力鼓励本科生在各种项目研究活动中与研究生合作，这将向他们介绍创新的基础/应用研究技术，并加强他们的计算和编程技能。研究生将在该项目中发挥主导作用，并将找到机会为他们的论文和学位论文研究当代研究主题。该项目的活动和发现将带来与其他学科在交通、信息技术和计算机科学/工程等交叉领域的合作研究机会。据设想，这项研究可能会引发其其他研究活动，使全国和路易斯安那州的交通系统用户和提供者都受益。

Information and communication technologies continue to improve transportation data acquisition and performance monitoring capabilities for surface transportation systems. Currently, little information has been extracted from the massive amounts of data being collected in real time by traffic management centers (TMC) nationwide. Despite tremendous advances in transportation data collection technologies, no parallel efforts have been made to improve the existing performance measures by maximizing the utility of information extraction methods from both archived and real-time transportation data. Current measures in the form of point estimates of average travel time and delay are essentially properties derived from first-order statistics and do not adequately reveal certain local and system-wide properties such as smoothness, coarseness, regularity, homogeneity, entropy, and others. Such properties can only be unraveled by advanced procedures and second-order statistics that are capable of characterizing the quality of traffic operations by exploiting spatiotemporal dependencies and textural features of constructed spatiotemporal traffic contour maps, a concept that is similar to texture characterization of digital images. The primary objectives to be achieved in this research are: (1) develop a new class of performance measures by quantifying special features of spatiotemporal contour maps; (2) study the behavior of traffic during transient stages using the new performance measures; (3) establish a procedure for on-line and off-line performance assessment for extended freeway segments; (4) investigate the correlation between the new measures and accident frequency and severity; (5) compare textural characteristics of recurrent and non-recurrent conditions; and (6) develop an implementation module of the new measures to be executed in real time by TMCs. The project examines spatiotemporal freeway traffic contour maps to improve the existing freeway performance measures and to identify precursor conditions for freeway congestion and crashes. Undergraduate students will be strongly encouraged to collaborate with graduate students in the various project research activities, which will introduce them to innovative basic/applied research techniques and strengthen their computational and programming skills. Graduate students will have a leading role in the project and will find opportunities to work on contemporary research topics for their theses and dissertations. The activities and findings of this project will lead to collaborative research opportunities with other disciplines at the intersection areas of transportation, information technology, and computer science/engineering. It is also envisioned that this research study will potentially spark other ITS research activities that would extend benefits to both transportation system users and providers nationwide and within the state of Louisiana.