上海市快速路系统交通衔接对策研究

本文首先对上海市快速路系统内部及其与周边关联路网之间的衔接中已有和潜在的交通拥堵问题进行分析 ,在此基础上 ,以避免在接合部周边区域形成交通拥堵、使快速路系统更好地发挥其应有的效益为目标 ,提出相应对策     

An information-based color feature representation and its application in detecting adult images

For many image classification tasks, color histogram is usually employed as an important “signature” to describe the color distribution of the image and infer the image content. However, most traditional color histograms cannot achieve satisfactory results in many image classification systems. In order to improve the accuracy and reduce the computational complexity of the classification task, an information-based color feature representation is proposed in this paper. The mutual information between the feature and the class label is adopted to evaluate the discriminative power of the feature. A novel quantization scheme is presented, which removes the redundant color components and combines the adjacent components together to generate a new feature to maximize the discriminative ability. An iterative algorithm is performed to derive the color space quantization and color feature generation. In order to illustrate the effectiveness of the proposed color representation, a specific image classification task, i.e., differentiating the adult images from benign ones, is employed. Experimental results show that our color feature achieves better classification performance and better efficiency compared with the traditional color histogram.     

Detecting shifted double JPEG compression tampering utilizing both intra-block and inter-block correlations

Copy-paste forgery is a very common type of forgery in JPEG images.The tampered patch has always suffered from JPEG compression twice with inconsistent block segmentation.This phenomenon in JPEG image forgeries is called the shifted double JPEG(SDJPEG) compression.Detection of SDJPEG compressed image patches can make crucial contribution to detect and locate the tampered region.However,the existing SDJPEG compression tampering detection methods cannot achieve satisfactory results especially when the tampered region is small.In this paper,an effective SDJPEG compression tampering detection method utilizing both intra-block and inter-block correlations is proposed.Statistical artifacts are left by the SDJPEG compression among the magnitudes of JPEG quantized discrete cosine transform(DCT) coefficients.Firstly,difference 2D arrays,which describe the differences between the magnitudes of neighboring JPEG quantized DCT coefficients on the intrablock and inter-block,are used to enhance the SDJPEG compression artifacts.Then,the thresholding technique is used to deal with these difference 2D arrays for reducing computational cost.After that,co-occurrence matrix is used to model these difference 2D arrays so as to take advantage of second-order statistics.All elements of these co-occurrence matrices are served as features for SDJPEG compression tampering detection.Finally,support vector machine(SVM) classifier is employed to distinguish the SDJPEG compressed image patches from the single JPEG compressed image patches using the developed feature set.Experimental results demonstrate the efficiency of the proposed method.     

高架快速路出口匝道衔接段交通组织方案研究

高架快速路出口匝道与地面交叉口衔接段的交通组织方案对城市交通系统作用至关重要。该文结合上海市中心城高架快速路,对高架快速路出口匝道衔接段交通组织方案进行了分析,可供今后类似工程借鉴、参考。     

上海新城交通规划建设的思考

新城开发建设是上海优化城市空间结构布局的重要战略手段。“十四五”时期,上海加快形成“中心辐射、两翼齐飞、新城发力、南北转型”的空间新格局,将嘉定、青浦、松江、奉贤、南汇等5个新城,培育成为独立的综合性节点城市。本文在回顾上海新城发展的基础上,对新一轮新城交通发展的要求进行总结,提出了上海新一轮新城交通发展需处理好主和辅、快和慢、外和内、老和新、客和货五对关键关系,形成支撑新城交通高质量发展的相关思考。