Traffic sign recognition (TSR, or Road Sign Recognition, RSR) is one of the Advanced Driver Assistance System (ADAS) devices in modern cars. To concern the most important issues, which are real-time and resource effic...Traffic sign recognition (TSR, or Road Sign Recognition, RSR) is one of the Advanced Driver Assistance System (ADAS) devices in modern cars. To concern the most important issues, which are real-time and resource efficiency, we propose a high efficiency hardware implementation for TSR. We divide the TSR procedure into two stages, detection and recognition. In the detection stage, under the assumption that most German traffic signs have red or blue colors with circle, triangle or rectangle shapes, we use Normalized RGB color transform and Single-Pass Connected Component Labeling (CCL) to find the potential traffic signs efficiently. For Single-Pass CCL, our contribution is to eliminate the “merge-stack” operations by recording connected relations of region in the scan phase and updating the labels in the iterating phase. In the recognition stage, the Histogram of Oriented Gradient (HOG) is used to generate the descriptor of the signs, and we classify the signs with Support Vector Machine (SVM). In the HOG module, we analyze the required minimum bits under different recognition rate. The proposed method achieves 96.61% detection rate and 90.85% recognition rate while testing with the GTSDB dataset. Our hardware implementation reduces the storage of CCL and simplifies the HOG computation. Main CCL storage size is reduced by 20% comparing to the most advanced design under typical condition. By using TSMC 90 nm technology, the proposed design operates at 105 MHz clock rate and processes in 135 fps with the image size of 1360 × 800. The chip size is about 1 mm2 and the power consumption is close to 8 mW. Therefore, this work is resource efficient and achieves real-time requirement.展开更多
为探究天气和道路等特征,以及交通流、天气、道路及时间等多维动态特征之间的交互作用对实时事故风险预测模型精度的影响,本文基于京哈高速公路北京段的事故数据,以及匹配的交通传感器数据、天气数据和道路特征等,构建4个数据集,分别为...为探究天气和道路等特征,以及交通流、天气、道路及时间等多维动态特征之间的交互作用对实时事故风险预测模型精度的影响,本文基于京哈高速公路北京段的事故数据,以及匹配的交通传感器数据、天气数据和道路特征等,构建4个数据集,分别为只包含交通流变量,包含交通流变量、天气及时间特征变量,包含交通流变量、道路及时间特征变量,包含交通流变量、天气、道路及时间特征变量。从考虑多维动态特征的交互效应出发,基于深度交叉网络,提出一种新的实时事故风险预测模型。结果显示,本文所构建的深度交叉网络模型比其他几种实时事故风险预测方法显示出更高的精度。模型的AUC值(Area Under Curve)可达0.8562,在0.2的概率阈值下,可以正确分类84.26%的非事故数据和77.55%事故数据。结论表明,本文采用的多维动态特征交互样本条件下的深度交叉网络模型能够有效地预测高速公路交通事故,可为我国高速公路安全管理部门提供理论与技术支持。展开更多
文摘Traffic sign recognition (TSR, or Road Sign Recognition, RSR) is one of the Advanced Driver Assistance System (ADAS) devices in modern cars. To concern the most important issues, which are real-time and resource efficiency, we propose a high efficiency hardware implementation for TSR. We divide the TSR procedure into two stages, detection and recognition. In the detection stage, under the assumption that most German traffic signs have red or blue colors with circle, triangle or rectangle shapes, we use Normalized RGB color transform and Single-Pass Connected Component Labeling (CCL) to find the potential traffic signs efficiently. For Single-Pass CCL, our contribution is to eliminate the “merge-stack” operations by recording connected relations of region in the scan phase and updating the labels in the iterating phase. In the recognition stage, the Histogram of Oriented Gradient (HOG) is used to generate the descriptor of the signs, and we classify the signs with Support Vector Machine (SVM). In the HOG module, we analyze the required minimum bits under different recognition rate. The proposed method achieves 96.61% detection rate and 90.85% recognition rate while testing with the GTSDB dataset. Our hardware implementation reduces the storage of CCL and simplifies the HOG computation. Main CCL storage size is reduced by 20% comparing to the most advanced design under typical condition. By using TSMC 90 nm technology, the proposed design operates at 105 MHz clock rate and processes in 135 fps with the image size of 1360 × 800. The chip size is about 1 mm2 and the power consumption is close to 8 mW. Therefore, this work is resource efficient and achieves real-time requirement.
文摘为探究天气和道路等特征,以及交通流、天气、道路及时间等多维动态特征之间的交互作用对实时事故风险预测模型精度的影响,本文基于京哈高速公路北京段的事故数据,以及匹配的交通传感器数据、天气数据和道路特征等,构建4个数据集,分别为只包含交通流变量,包含交通流变量、天气及时间特征变量,包含交通流变量、道路及时间特征变量,包含交通流变量、天气、道路及时间特征变量。从考虑多维动态特征的交互效应出发,基于深度交叉网络,提出一种新的实时事故风险预测模型。结果显示,本文所构建的深度交叉网络模型比其他几种实时事故风险预测方法显示出更高的精度。模型的AUC值(Area Under Curve)可达0.8562,在0.2的概率阈值下,可以正确分类84.26%的非事故数据和77.55%事故数据。结论表明,本文采用的多维动态特征交互样本条件下的深度交叉网络模型能够有效地预测高速公路交通事故,可为我国高速公路安全管理部门提供理论与技术支持。