Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanne...Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh environments.This paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention mechanism.The mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network structure.Combined with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid recovery.Simulation results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing studies.The results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art model.Furthermore,by the ablation study,the contributions of each different improvement are compared.The proposed model can be used to support resilient network design for real-time mission execution.展开更多
In recent years,with the rapid development of e-commerce,people need to classify the wide variety and a large number of clothing images appearing on e-commerce platforms.In order to solve the problems of long time con...In recent years,with the rapid development of e-commerce,people need to classify the wide variety and a large number of clothing images appearing on e-commerce platforms.In order to solve the problems of long time consumption and unsatisfactory classification accuracy arising from the classification of a large number of clothing images,researchers have begun to exploit deep learning techniques instead of traditional learning methods.The paper explores the use of convolutional neural networks(CNNs)for feature learning to enhance global feature information interactions by adding an improved hybrid attention mechanism(HAM)that fully utilizes feature weights in three dimensions:channel,height,and width.Moreover,the improved pooling layer not only captures local feature information,but also fuses global and local information to improve the misclassification problem that occurs between similar categories.Experiments on the Fashion-MNIST and DeepFashion datasets show that the proposed method significantly improves the accuracy of clothing classification(93.62%and 67.9%)compared with residual network(ResNet)and convolutional block attention module(CBAM).展开更多
The recommendation system can effectively and quickly provide valuable information for users by filtering out massive useless data. User behavior modeling can extract all kinds of aggregated features over the heteroge...The recommendation system can effectively and quickly provide valuable information for users by filtering out massive useless data. User behavior modeling can extract all kinds of aggregated features over the heterogeneous behaviors to help recommendation. However, the existing user behavior modeling method cannot solve the cold-start problem caused by data sparse. Recent recommender systems which exploit reviews for learning representation can alleviate the above problem to a certain extent. Therefore, a user behavior modeling is proposed for recommendation task using attention neural network based on user reviews (AT-UBM). Firstly vanilla attention was used to sample reviews, and then CNN+Pooling method was applied to extract user behavior features. Finally the long-term behavior was combined with short-term behavior in feature spaces. Experimental results on real datasets show that the review-based user behavior model has better prediction accuracy and generalization capability.展开更多
针对无人机视角下的小目标检测精度较差、漏检较为严重的问题,提出一种基于改进YOLOv5的无人机图像检测算法。针对小目标尺度较小问题在骨干网络替换空间金字塔池化(Spatial Pyramid Pooling,SPP)为SPPCSPC-GS,增强密集区域关注能力,提...针对无人机视角下的小目标检测精度较差、漏检较为严重的问题,提出一种基于改进YOLOv5的无人机图像检测算法。针对小目标尺度较小问题在骨干网络替换空间金字塔池化(Spatial Pyramid Pooling,SPP)为SPPCSPC-GS,增强密集区域关注能力,提取更多小目标有效特征;在颈部网络中引入CBAM注意力机制将头部C3模块替换为C3CBAM增强上下文信息,提高空间与通道特征表达能力;针对遮挡问题引入柔性非极大值抑制(Soft Non Maximum Suppression,Soft NMS)提升模型对遮挡和密集目标的检测能力;替换损失函数为EIOU加快收敛提升定位效果。改进后的模型在VisDrone数据集上平均检测精度为42.2%,相较于原始YOLOv5s算法提升10.7%,遮挡严重的小目标行人与人类别精度分别上升12%与13.3%。相较于其他先进算法,所提算法表现优秀,可以满足无人机视角图像检测任务要求。展开更多
基金the National Natural Science Foundation of China(NNSFC)(Grant Nos.72001213 and 72301292)the National Social Science Fund of China(Grant No.19BGL297)the Basic Research Program of Natural Science in Shaanxi Province(Grant No.2021JQ-369).
文摘Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh environments.This paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention mechanism.The mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network structure.Combined with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid recovery.Simulation results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing studies.The results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art model.Furthermore,by the ablation study,the contributions of each different improvement are compared.The proposed model can be used to support resilient network design for real-time mission execution.
文摘In recent years,with the rapid development of e-commerce,people need to classify the wide variety and a large number of clothing images appearing on e-commerce platforms.In order to solve the problems of long time consumption and unsatisfactory classification accuracy arising from the classification of a large number of clothing images,researchers have begun to exploit deep learning techniques instead of traditional learning methods.The paper explores the use of convolutional neural networks(CNNs)for feature learning to enhance global feature information interactions by adding an improved hybrid attention mechanism(HAM)that fully utilizes feature weights in three dimensions:channel,height,and width.Moreover,the improved pooling layer not only captures local feature information,but also fuses global and local information to improve the misclassification problem that occurs between similar categories.Experiments on the Fashion-MNIST and DeepFashion datasets show that the proposed method significantly improves the accuracy of clothing classification(93.62%and 67.9%)compared with residual network(ResNet)and convolutional block attention module(CBAM).
文摘The recommendation system can effectively and quickly provide valuable information for users by filtering out massive useless data. User behavior modeling can extract all kinds of aggregated features over the heterogeneous behaviors to help recommendation. However, the existing user behavior modeling method cannot solve the cold-start problem caused by data sparse. Recent recommender systems which exploit reviews for learning representation can alleviate the above problem to a certain extent. Therefore, a user behavior modeling is proposed for recommendation task using attention neural network based on user reviews (AT-UBM). Firstly vanilla attention was used to sample reviews, and then CNN+Pooling method was applied to extract user behavior features. Finally the long-term behavior was combined with short-term behavior in feature spaces. Experimental results on real datasets show that the review-based user behavior model has better prediction accuracy and generalization capability.
文摘针对无人机视角下的小目标检测精度较差、漏检较为严重的问题,提出一种基于改进YOLOv5的无人机图像检测算法。针对小目标尺度较小问题在骨干网络替换空间金字塔池化(Spatial Pyramid Pooling,SPP)为SPPCSPC-GS,增强密集区域关注能力,提取更多小目标有效特征;在颈部网络中引入CBAM注意力机制将头部C3模块替换为C3CBAM增强上下文信息,提高空间与通道特征表达能力;针对遮挡问题引入柔性非极大值抑制(Soft Non Maximum Suppression,Soft NMS)提升模型对遮挡和密集目标的检测能力;替换损失函数为EIOU加快收敛提升定位效果。改进后的模型在VisDrone数据集上平均检测精度为42.2%,相较于原始YOLOv5s算法提升10.7%,遮挡严重的小目标行人与人类别精度分别上升12%与13.3%。相较于其他先进算法,所提算法表现优秀,可以满足无人机视角图像检测任务要求。