图对比学习因其可有效缓解数据稀疏问题被广泛应用在推荐系统中.然而,目前大多数基于图对比学习的推荐算法均采用单一视角进行学习,这极大地限制了模型的泛化能力,且图卷积网络本身存在的过度平滑问题也影响着模型的稳定性.基于此,提出...图对比学习因其可有效缓解数据稀疏问题被广泛应用在推荐系统中.然而,目前大多数基于图对比学习的推荐算法均采用单一视角进行学习,这极大地限制了模型的泛化能力,且图卷积网络本身存在的过度平滑问题也影响着模型的稳定性.基于此,提出一种融合层注意力机制的多视角图对比学习推荐方法.一方面,该方法提出2种不同视角下的3种对比学习,在视图级视角下,通过对原始图添加随机噪声构建扰动增强视图,利用奇异值分解(singular value decomposition)重组构建SVD增强视图,对这2个增强视图进行视图级对比学习;在节点视角下,利用节点间的语义信息分别进行候选节点和候选结构邻居对比学习,并将3种对比学习辅助任务和推荐任务进行多任务学习优化,以提高节点嵌入的质量,从而提升模型的泛化能力.另一方面,在图卷积网络学习用户和项目的节点嵌入时,采用层注意力机制的方式聚合最终的节点嵌入,提高模型的高阶连通性,以缓解过度平滑问题.在4个公开数据集LastFM,Gowalla,Ifashion,Yelp上与10个经典模型进行对比,结果表明该方法在Recall,Precision,NDCG这3个指标上分别平均提升3.12%,3.22%,4.06%,这说明所提方法是有效的.展开更多
In this paper, we proposed a multi-task system that can identify dish types, food ingredients, and cooking methods from food images with deep convolutional neural networks. We built up a dataset of 360 classes of diff...In this paper, we proposed a multi-task system that can identify dish types, food ingredients, and cooking methods from food images with deep convolutional neural networks. We built up a dataset of 360 classes of different foods with at least 500 images for each class. To reduce the noises of the data, which was collected from the Internet, outlier images were detected and eliminated through a one-class SVM trained with deep convolutional features. We simultaneously trained a dish identifier, a cooking method recognizer, and a multi-label ingredient detector. They share a few low-level layers in the deep network architecture. The proposed framework shows higher accuracy than traditional method with handcrafted features, and the cooking method recognizer and ingredient detector can be applied to dishes which are not included in the training dataset to provide reference information for users.展开更多
跨年龄人脸识别技术可以应用在刑事侦查、社会安全、人口管理等诸多领域,具有广泛的应用前景。对跨年龄人脸识别技术进行研究,主要难点是年龄增长带来的面部变化。为应对这一难点,设计了基于多任务学习的跨年龄人脸识别系统,该系统具有...跨年龄人脸识别技术可以应用在刑事侦查、社会安全、人口管理等诸多领域,具有广泛的应用前景。对跨年龄人脸识别技术进行研究,主要难点是年龄增长带来的面部变化。为应对这一难点,设计了基于多任务学习的跨年龄人脸识别系统,该系统具有去除年龄因素影响、面对跨年龄人脸具有更强鲁棒性等优点,并通过实验证明了该系统可以提高在跨年龄人脸识别数据库Morph Album 2的识别准确率。展开更多
文摘图对比学习因其可有效缓解数据稀疏问题被广泛应用在推荐系统中.然而,目前大多数基于图对比学习的推荐算法均采用单一视角进行学习,这极大地限制了模型的泛化能力,且图卷积网络本身存在的过度平滑问题也影响着模型的稳定性.基于此,提出一种融合层注意力机制的多视角图对比学习推荐方法.一方面,该方法提出2种不同视角下的3种对比学习,在视图级视角下,通过对原始图添加随机噪声构建扰动增强视图,利用奇异值分解(singular value decomposition)重组构建SVD增强视图,对这2个增强视图进行视图级对比学习;在节点视角下,利用节点间的语义信息分别进行候选节点和候选结构邻居对比学习,并将3种对比学习辅助任务和推荐任务进行多任务学习优化,以提高节点嵌入的质量,从而提升模型的泛化能力.另一方面,在图卷积网络学习用户和项目的节点嵌入时,采用层注意力机制的方式聚合最终的节点嵌入,提高模型的高阶连通性,以缓解过度平滑问题.在4个公开数据集LastFM,Gowalla,Ifashion,Yelp上与10个经典模型进行对比,结果表明该方法在Recall,Precision,NDCG这3个指标上分别平均提升3.12%,3.22%,4.06%,这说明所提方法是有效的.
基金This work was supported by the National High Technology Research and Development 863 Program of China under Grant No. 2013AA013903, the National Natural Science Foundation of China under Grant No. 61373069, the Research Grant of Beijing Higher Institution Engineering Research Center, and the Tsinghua University Initiative Scientific Research Program.
文摘In this paper, we proposed a multi-task system that can identify dish types, food ingredients, and cooking methods from food images with deep convolutional neural networks. We built up a dataset of 360 classes of different foods with at least 500 images for each class. To reduce the noises of the data, which was collected from the Internet, outlier images were detected and eliminated through a one-class SVM trained with deep convolutional features. We simultaneously trained a dish identifier, a cooking method recognizer, and a multi-label ingredient detector. They share a few low-level layers in the deep network architecture. The proposed framework shows higher accuracy than traditional method with handcrafted features, and the cooking method recognizer and ingredient detector can be applied to dishes which are not included in the training dataset to provide reference information for users.
文摘跨年龄人脸识别技术可以应用在刑事侦查、社会安全、人口管理等诸多领域,具有广泛的应用前景。对跨年龄人脸识别技术进行研究,主要难点是年龄增长带来的面部变化。为应对这一难点,设计了基于多任务学习的跨年龄人脸识别系统,该系统具有去除年龄因素影响、面对跨年龄人脸具有更强鲁棒性等优点,并通过实验证明了该系统可以提高在跨年龄人脸识别数据库Morph Album 2的识别准确率。
