为了提升汽车辅助系统对前方障碍物的检测效果并进一步获取精确的距离信息,文章提出了一种基于改进YOLOv8s的交通场景障碍物检测与双目测距方法。该方法以YOLOv8s(You Only Look Once v8s)网络为基础,首先在Backbone中引入EMA注意力机制...为了提升汽车辅助系统对前方障碍物的检测效果并进一步获取精确的距离信息,文章提出了一种基于改进YOLOv8s的交通场景障碍物检测与双目测距方法。该方法以YOLOv8s(You Only Look Once v8s)网络为基础,首先在Backbone中引入EMA注意力机制,以提高目标检测精度;其次将Neck中的PANFPN网络替换为ASF(Attentional Scale Sequence Fusion)网络,并采用DIoU优化损失函数;在特征匹配算法ORB的基础上,利用RANSAC算法剔除误匹配的点对。通过在KITTI数据集和实际交通场景中的实验,结果表明,在20 m的距离范围内,改进后的YOLOv8s网络对汽车、行人和非机动车3类障碍物的检测mAP(mean average precision)达到了91.1%,提高了4.8%,同时测距的平均误差仅为1.55%。展开更多
由于数字乳腺体层合成摄影(Digital Breast Tomosynthesis,DBT)扫描成像原理异于传统二维乳腺X线摄影(DM),而DM图像检测方法已不适用于DBT。因此,本文针对DBT的特性,对伪影扩散函数、系统MTF和几何失真等关键参数的检测方法进行研究,并...由于数字乳腺体层合成摄影(Digital Breast Tomosynthesis,DBT)扫描成像原理异于传统二维乳腺X线摄影(DM),而DM图像检测方法已不适用于DBT。因此,本文针对DBT的特性,对伪影扩散函数、系统MTF和几何失真等关键参数的检测方法进行研究,并给出相应的分析计算方法、Matlab程序算法实现及实际检测结果。结果表明,伪影扩散函数结果符合意大利医学物理协会(AIFM)评估的典型范围或厂家质控(联影)要求,且均小于15mm;系统MTF曲线上50%处的测量值不小于1.3LP/mm;几何失真小于5%。展开更多
Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and...Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and treatment(Wang et al. 2023). Due to its enormous economic and social impact, it is listed as a notifiable animal disease by the World Organization for Animal Health(Costard et al. 2013). Although ASF has been present in Sub-Saharan Africa since its first discovery in Kenya.展开更多
African swine fever(ASF),caused by the African swine fever virus(ASFV),has brought enormous economic loss and represents a major threat to the global pig industry(Vergne et al.2017).ASFVs are divided into 24 genotypes...African swine fever(ASF),caused by the African swine fever virus(ASFV),has brought enormous economic loss and represents a major threat to the global pig industry(Vergne et al.2017).ASFVs are divided into 24 genotypes based on their B646L gene,with only genotypes Ⅰ and Ⅱ circulating globally(Dixon et al.2019).展开更多
文摘为了提升汽车辅助系统对前方障碍物的检测效果并进一步获取精确的距离信息,文章提出了一种基于改进YOLOv8s的交通场景障碍物检测与双目测距方法。该方法以YOLOv8s(You Only Look Once v8s)网络为基础,首先在Backbone中引入EMA注意力机制,以提高目标检测精度;其次将Neck中的PANFPN网络替换为ASF(Attentional Scale Sequence Fusion)网络,并采用DIoU优化损失函数;在特征匹配算法ORB的基础上,利用RANSAC算法剔除误匹配的点对。通过在KITTI数据集和实际交通场景中的实验,结果表明,在20 m的距离范围内,改进后的YOLOv8s网络对汽车、行人和非机动车3类障碍物的检测mAP(mean average precision)达到了91.1%,提高了4.8%,同时测距的平均误差仅为1.55%。
文摘由于数字乳腺体层合成摄影(Digital Breast Tomosynthesis,DBT)扫描成像原理异于传统二维乳腺X线摄影(DM),而DM图像检测方法已不适用于DBT。因此,本文针对DBT的特性,对伪影扩散函数、系统MTF和几何失真等关键参数的检测方法进行研究,并给出相应的分析计算方法、Matlab程序算法实现及实际检测结果。结果表明,伪影扩散函数结果符合意大利医学物理协会(AIFM)评估的典型范围或厂家质控(联影)要求,且均小于15mm;系统MTF曲线上50%处的测量值不小于1.3LP/mm;几何失真小于5%。
基金supported by the National Key Research and Development Program of China (2021YFD1800100)the earmarked fund for China Agriculture Research System (CARS-35)。
文摘Although African swine fever(ASF) has been prevalent for more than a century, it remains the number one swine disease that seriously endangers the global pig industry, and there is no effective means of prevention and treatment(Wang et al. 2023). Due to its enormous economic and social impact, it is listed as a notifiable animal disease by the World Organization for Animal Health(Costard et al. 2013). Although ASF has been present in Sub-Saharan Africa since its first discovery in Kenya.
基金supported by the National Natural Science Fund for Distinguished Young Scholars of China(31925036 and 32025034)the Shandong Provincial Key R&D Program,China(2021LZGC001)+3 种基金the Biological Breeding-Major Projects,Institute of Zoology,Chinese Academy of Sciences and Institute of Animal Science,Chinese Academy of Agricultural Sciences(2023ZD04074 and 2023ZD0404604)the Special Project of Longhu Laboratory,China(LHLab_ZD20230012)the National Natural Science Foundation of China(32230100,32330099 and 32201257)the National Key Research and Development Program of China(2020YFA0509503,2022YFF0710703,2021YFA0805902 and 2022XAGG0121,2022YFF1002803).
文摘African swine fever(ASF),caused by the African swine fever virus(ASFV),has brought enormous economic loss and represents a major threat to the global pig industry(Vergne et al.2017).ASFVs are divided into 24 genotypes based on their B646L gene,with only genotypes Ⅰ and Ⅱ circulating globally(Dixon et al.2019).
