提出了基于连通域标记算法对裂缝图像内的孔洞进行分类统计,并按照公路技术状况评定标准要求对裂缝的种类进行划分.同时,应用改进骨架化算法对划分所得的裂缝进行特征信息获取.试验结果表明,该算法对于裂缝分类具有非常高的准确性,并且对裂缝测量也具有较好的稳定性与准确性,是一种有效的路面裂缝自动分类与测量的方法.

为探究入-出连续匝道对城市快速路的影响,该文利用微观交通仿真软件TSIS进行相关建模以及仿真工作.利用实地调查采集得到的交通流量、车辆速度、几何条件等数据,对TSIS部分参数进行调整,以使仿真结果可以接受(与实测数据偏差在5％以内).模型标定结束后,根据道路通行能力以及服务水平,选定4种等级以及流量,分别进行仿真,参考平均车速以及换道数,得到各自流量下,入-出匝道对城市快速路主线影响范围.结果表明:1)入-出组合匝道对主线上游的影响范围要大于对主线下游段的影响范围;2)入-出组合匝道随着主线交通流流量的增加,对主线上下游的影响范围增大.

数字图像技术的发展使得路面病害破损的调查更加容易和安全,然而路面病害的自动识别技术还不能良好地适应当前复杂的路面情况.因此对传统的数字采集,人工参与判断的路面病害识别过程的效率提升尤为必要.针对这一需求,提出一种基于裂缝横断面灰度曲线图以及裂缝几何走势的裂缝信息提取方法.先获得横断面灰度曲线,从裂缝中心向两边寻找满足一定强度的边缘走势,由两端距离获得该断面裂缝宽度.通过一定数量的裂缝横断面信息综合得出该条裂缝的最大和平均宽度、裂缝长度等信息.该方法对于不同环境和人力参与下的裂缝判别有较好的稳定性,同时边缘强度的判别具有自适应功能.结果表明这种方法对于裂缝信息的识别有较好的效果.

Investigations indicate that direct-left-turns (DLT) at signalized intersections create many conflicts and disturbances. A U-turn is a traffic organization method to improve the safety of the left turning vehicles. There are two forms of U-turns, depending on the location of U-turn bay. This paper researches the optimal location of the U-turn bay, taking a typical signalized intersection as an example, and compares the effectiveness of the two cases. Based on the microscopic traffic simulation software TSIS, this paper makes a contrast of the Travel Time Total, Speed Average, as well as Speed Variance of the two forms of U-turn. According to the analytical and simulation results, it can be found that the U-turn is more effective than the DLT, and the First form is more prominent in increasing the speed average and lowering the speed variance in the particular situation tested.

Facing the worldwide climate change and environment deterioration,and as a major part of the world's carbon dioxide emissions,the Low-carbon trend in the transportation system is imperative.Therefore,Low-carbon transportation system in urban area is consequent and important.Through the analysis of Shanghai urban traffic conditions,a goal is presented that develops Shanghai Low-carbon urban traffic.This paper suggests dividing the work of establishing Low-carbon urban traffic system into three subjects,including the responsibilities of government,companies,and residents.For each subject,the paper points out the duty.Finally,some suggestions and recommendations are provided for the future development of low-carbon transportation in Shanghai.