Achieving accurate and automated tumor segmentation plays an important role in both clinical practice and radiomics research. Segmentation in medicine is now often performed manually by experts, which is a laborious, expensive and error-prone task. Manual annotation relies heavily on the experience and knowledge of these experts. In addition, there is much intra- and interobserver variation. Therefore, it is of great significance to develop a method that can automatically segment tumor target regions. In this paper, we propose a deep learning segmentation method based on multimodal positron emission tomography-computed tomography (PET-CT), which combines the high sensitivity of PET and the precise anatomical information of CT. We design an improved spatial attention network(ISA-Net) to increase the accuracy of PET or CT in detecting tumors, which uses multi-scale convolution operation to extract feature information and can highlight the tumor region location information and suppress the non-tumor region location information. In addition, our network uses dual-channel inputs in the coding stage and fuses them in the decoding stage, which can take advantage of the differences and complementarities between PET and CT. We validated the proposed ISA-Net method on two clinical datasets, a soft tissue sarcoma(STS) and a head and neck tumor(HECKTOR) dataset, and compared with other attention methods for tumor segmentation. The DSC score of 0.8378 on STS dataset and 0.8076 on HECKTOR dataset show that ISA-Net method achieves better segmentation performance and has better generalization. Conclusions: The method proposed in this paper is based on multi-modal medical image tumor segmentation, which can effectively utilize the difference and complementarity of different modes. The method can also be applied to other multi-modal data or single-modal data by proper adjustment.
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背景:基于其可变的历史视觉记录,对青少年的球形等效物进行定量预测。方法:从2019年10月到2022年3月,我们检查了来自中国成都成都6-20岁的37,586名青少年的双眼未校正视力,轴向长度,角膜曲率和轴向75,172眼。 80 \%样品由训练集和剩余的20 \%组成测试集。时间感知的长期短期记忆被用来定量预测青少年在两年半内的球形当量。结果:球形当量的测试集的平均绝对预测误差为0.273-0.257,如果我们考虑不同的历史记录和不同的预测持续时间,则从0.189-0.160到0.596-0.473。结论:时间感知时间长的短期记忆被应用于不规则采样时间序列中的时间特征,这更符合实际数据的特征,因此具有更高的适用性,并有助于较早地识别近视的进展。总体误差0.273远小于临床上可接受预测的标准,例如0.75。
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由于基于相交的联盟(IOU)优化维持最终IOU预测度量和损失的一致性,因此它已被广泛用于单级2D对象检测器的回归和分类分支。最近,几种3D对象检测方法采用了基于IOU的优化,并用3D iou直接替换了2D iou。但是,由于复杂的实施和效率低下的向后操作,3D中的这种直接计算非常昂贵。此外,基于3D IOU的优化是优化的,因为它对旋转很敏感,因此可能导致训练不稳定性和检测性能恶化。在本文中,我们提出了一种新型的旋转旋转iou(RDIOU)方法,该方法可以减轻旋转敏感性问题,并在训练阶段与3D IOU相比产生更有效的优化目标。具体而言,我们的RDIOU通过将旋转变量解耦为独立术语,但保留3D iou的几何形状来简化回归参数的复杂相互作用。通过将RDIOU纳入回归和分类分支,鼓励网络学习更精确的边界框,并同时克服分类和回归之间的错位问题。基准Kitti和Waymo开放数据集的广泛实验验证我们的RDIOU方法可以为单阶段3D对象检测带来实质性改进。
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学习的推荐系统可能会无意间泄露有关其培训数据的信息,从而导致侵犯隐私行为。我们调查了推荐系统通过成员推理面临的隐私威胁。在这种攻击中,对手旨在推断用户的数据是否用于训练目标推荐人。为了实现这一目标,以前的工作使用了阴影推荐人来为攻击模型得出训练数据,然后通过计算用户历史互动和推荐项目之间的差异向量来预测成员资格。最先进的方法面临两个具有挑战性的问题:(1)由于阴影和目标推荐人之间的差距,攻击模型的培训数据偏见,并且(2)推荐人中的隐藏状态没有观察到,导致估计不准确差矢量。为了解决上述局限性,我们提出了针对推荐系统(DL-MIA)框架的成员推理攻击的偏见学习,该框架具有四个主要组件:(1)差异向量生成器,(2)分发式编码器,(3)重量估算器和(4)攻击模型。为了减轻推荐人之间的差距,设计了基于变异的自动编码器(VAE)的分解编码器,以识别推荐人不变和特定功能。为了减少估计偏差,我们设计了一个权重估计器,为每个差异向量分配了真实级别的得分,以指示估计精度。我们对三个现实世界数据集的一般推荐人和顺序推荐人评估了DL-MIA。实验结果表明,DL-MIA有效地减轻了同时减轻培训和估计的偏见,并实现了最先进的攻击性能。
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图表学习目的旨在将节点内容与图形结构集成以学习节点/图表示。然而,发现许多现有的图形学习方法在具有高异性级别的数据上不能很好地工作,这是不同类标签之间很大比例的边缘。解决这个问题的最新努力集中在改善消息传递机制上。但是,尚不清楚异质性是否确实会损害图神经网络(GNNS)的性能。关键是要展现一个节点与其直接邻居之间的关系,例如它们是异性还是同质性?从这个角度来看,我们在这里研究了杂质表示在披露连接节点之间的关系之前/之后的杂音表示的作用。特别是,我们提出了一个端到端框架,该框架既学习边缘的类型(即异性/同质性),并利用边缘类型的信息来提高图形神经网络的表现力。我们以两种不同的方式实施此框架。具体而言,为了避免通过异质边缘传递的消息,我们可以通过删除边缘分类器鉴定的异性边缘来优化图形结构。另外,可以利用有关异性邻居的存在的信息进行特征学习,因此,设计了一种混合消息传递方法来汇总同质性邻居,并根据边缘分类使异性邻居多样化。广泛的实验表明,在整个同质级别的多个数据集上,通过在多个数据集上提出的框架对GNN的绩效提高了显着提高。
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Graph Neural Networks (GNNs) have shown satisfying performance on various graph learning tasks. To achieve better fitting capability, most GNNs are with a large number of parameters, which makes these GNNs computationally expensive. Therefore, it is difficult to deploy them onto edge devices with scarce computational resources, e.g., mobile phones and wearable smart devices. Knowledge Distillation (KD) is a common solution to compress GNNs, where a light-weighted model (i.e., the student model) is encouraged to mimic the behavior of a computationally expensive GNN (i.e., the teacher GNN model). Nevertheless, most existing GNN-based KD methods lack fairness consideration. As a consequence, the student model usually inherits and even exaggerates the bias from the teacher GNN. To handle such a problem, we take initial steps towards fair knowledge distillation for GNNs. Specifically, we first formulate a novel problem of fair knowledge distillation for GNN-based teacher-student frameworks. Then we propose a principled framework named RELIANT to mitigate the bias exhibited by the student model. Notably, the design of RELIANT is decoupled from any specific teacher and student model structures, and thus can be easily adapted to various GNN-based KD frameworks. We perform extensive experiments on multiple real-world datasets, which corroborates that RELIANT achieves less biased GNN knowledge distillation while maintaining high prediction utility.
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With the development of technology and sharing economy, Airbnb as a famous short-term rental platform, has become the first choice for many young people to select. The issue of Airbnb's pricing has always been a problem worth studying. While the previous studies achieve promising results, there are exists deficiencies to solve. Such as, (1) the feature attributes of rental are not rich enough; (2) the research on rental text information is not deep enough; (3) there are few studies on predicting the rental price combined with the point of interest(POI) around the house. To address the above challenges, we proposes a multi-source information embedding(MSIE) model to predict the rental price of Airbnb. Specifically, we first selects the statistical feature to embed the original rental data. Secondly, we generates the word feature vector and emotional score combination of three different text information to form the text feature embedding. Thirdly, we uses the points of interest(POI) around the rental house information generates a variety of spatial network graphs, and learns the embedding of the network to obtain the spatial feature embedding. Finally, this paper combines the three modules into multi source rental representations, and uses the constructed fully connected neural network to predict the price. The analysis of the experimental results shows the effectiveness of our proposed model.
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Domain shift widely exists in the visual world, while modern deep neural networks commonly suffer from severe performance degradation under domain shift due to the poor generalization ability, which limits the real-world applications. The domain shift mainly lies in the limited source environmental variations and the large distribution gap between source and unseen target data. To this end, we propose a unified framework, Style-HAllucinated Dual consistEncy learning (SHADE), to handle such domain shift in various visual tasks. Specifically, SHADE is constructed based on two consistency constraints, Style Consistency (SC) and Retrospection Consistency (RC). SC enriches the source situations and encourages the model to learn consistent representation across style-diversified samples. RC leverages general visual knowledge to prevent the model from overfitting to source data and thus largely keeps the representation consistent between the source and general visual models. Furthermore, we present a novel style hallucination module (SHM) to generate style-diversified samples that are essential to consistency learning. SHM selects basis styles from the source distribution, enabling the model to dynamically generate diverse and realistic samples during training. Extensive experiments demonstrate that our versatile SHADE can significantly enhance the generalization in various visual recognition tasks, including image classification, semantic segmentation and object detection, with different models, i.e., ConvNets and Transformer.
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Deep latent variable models have achieved significant empirical successes in model-based reinforcement learning (RL) due to their expressiveness in modeling complex transition dynamics. On the other hand, it remains unclear theoretically and empirically how latent variable models may facilitate learning, planning, and exploration to improve the sample efficiency of RL. In this paper, we provide a representation view of the latent variable models for state-action value functions, which allows both tractable variational learning algorithm and effective implementation of the optimism/pessimism principle in the face of uncertainty for exploration. In particular, we propose a computationally efficient planning algorithm with UCB exploration by incorporating kernel embeddings of latent variable models. Theoretically, we establish the sample complexity of the proposed approach in the online and offline settings. Empirically, we demonstrate superior performance over current state-of-the-art algorithms across various benchmarks.
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Energy management systems (EMS) are becoming increasingly important in order to utilize the continuously growing curtailed renewable energy. Promising energy storage systems (ESS), such as batteries and green hydrogen should be employed to maximize the efficiency of energy stakeholders. However, optimal decision-making, i.e., planning the leveraging between different strategies, is confronted with the complexity and uncertainties of large-scale problems. Here, we propose a sophisticated deep reinforcement learning (DRL) methodology with a policy-based algorithm to realize the real-time optimal ESS planning under the curtailed renewable energy uncertainty. A quantitative performance comparison proved that the DRL agent outperforms the scenario-based stochastic optimization (SO) algorithm, even with a wide action and observation space. Owing to the uncertainty rejection capability of the DRL, we could confirm a robust performance, under a large uncertainty of the curtailed renewable energy, with a maximizing net profit and stable system. Action-mapping was performed for visually assessing the action taken by the DRL agent according to the state. The corresponding results confirmed that the DRL agent learns the way like what a human expert would do, suggesting reliable application of the proposed methodology.
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