学习合适的全幻灯片图像(WSIS)表示有效检索系统是一项非平凡的任务。从当前方法中获得的WSI嵌入在欧几里得空间中并不理想有效的WSI检索。此外,由于同时处理多组贴片,因此大多数当前方法都需要高GPU存储器。为了应对这些挑战,我们提出了一个新颖的框架,用于利用深层生成建模和Fisher向量学习二进制和稀疏的WSI表示。我们引入了新的损失功能,以学习稀疏和二进制置换不变的WSI表示,采用基于实例的培训来提高记忆效率。在癌症基因组地图集(​​TCGA)和肝脏-Kidney-Stomach(LKS)数据集上验证了博学的WSI表示。在检索准确性和速度方面,该方法的表现优于Yottixel(最新的组织病理学图像搜索引擎)。此外,我们在公共基准LKS数据集中对SOTA实现了竞争性能,以进行WSI分类。
translated by 谷歌翻译
联邦学习(FL)是一种分散的方法,使医院能够在不共享私人患者数据进行培训的情况下协作学习模型。在FL中,参与者医院定期交换培训结果,而不是使用中央服务器培训样品。但是,访问模型参数或梯度可以暴露私人培训数据样本。为了应对这一挑战,我们采用安全的多方计算(SMC)来建立一个保护隐私的联合学习框架。在我们提出的方法中,医院分为集群。在当地培训之后,每家医院在同一集群中分解了其他医院的模型权重,因此没有一家医院可以自己检索其他医院的体重。然后,所有医院总结了收到的权重,将结果发送到中央服务器。最后,中央服务器汇总了结果,检索模型的平均权重并更新模型,而无需访问各个医院的权重。我们在公开可用的存储库《癌症基因组图集》(TCGA)上进行实验。我们将提议框架的性能与差异隐私进行比较,并将平均为基准。结果表明,与差异隐私相比,我们的框架可以实现更高的准确性,而没有隐私泄漏风险,而较高的通信开销则可以实现。
translated by 谷歌翻译
深度神经网络无法推广到分布数据是一个众所周知的问题,并引起了人们对在安全关键领域(例如医疗保健,金融和自动驾驶汽车)部署训练的网络的担忧。我们研究了一种特定的分销偏移$ \ unicode {x2013} $快捷方式或培训数据中的虚假相关性。快捷方式学习通常仅在对不包含相同伪造相关性的现实世界数据进行评估时才能暴露出来,这使AI从业人员适当评估训练有素的现实世界应用模型的有效性构成了严重的困境。在这项工作中,我们建议在学习的表示和输入之间使用共同信息(MI)作为指标,以查找培训中的位置,网络锁定在快捷方式上。实验表明,MI可以用作监测快捷方式学习的域敏捷度量。
translated by 谷歌翻译
数字病理学的最新进展导致了对通过活检图像的数据库搜索的组织病理学图像检索(HIR)系统,以找到与给定查询图像的类似情况。这些HIR系统允许病理学家毫不费力地和有效地访问数千个先前诊断的病例,以便利用相应的病理报告中的知识。由于HIR系统可能需要处理数百万千兆像素图像,因此必须使用紧凑型图像特征的提取以允许有效准确的检索。在本文中,我们提出了克条形码的应用作为HIR系统的图像特征。与大多数特征生成方案不同,Gram条形码基于高阶统计,通过总结卷积神经网络层中的不同特征图之间的相关性来描述组织纹理。我们使用预先训练的VGG19网络在三个公共数据集中运行HIR实验,用于Gram条形码生成,展示高度竞争的结果。
translated by 谷歌翻译
我们分析了含有100,000个补丁的结直肠癌(CRC)组织病理学数据集的离线和在线三胞胎挖掘的效果。我们认为在线和离线采矿中,极端,即与给定锚的最远和最近的补丁。尽管许多工作仅着眼于在线选择三胞胎(批次),但我们还研究了以离线方式训练之前的极端距离和邻居补丁的效果。我们分析了极端案例的嵌入离线距离与在线采矿的影响,包括易于正面的,批处理半硬度,批处理硬线挖掘,邻里组件分析损失,其代理版本和距离加权采样。我们还根据极端距离进行了在线方法,并根据数据模式进行了全面比较离线和在线挖掘绩效,并将离线挖掘解释为具有大型迷你批量大小的在线挖掘的可拖延概括。同样,我们讨论了不同结直肠组织类型的关系。我们发现,离线和在线挖掘方法在本研究中具有可比的特定体系结构(例如RESNET-18)具有可比性的性能。此外,我们发现包括不同的极端距离在内的各种情况是有希望的,尤其是在在线方法中。
translated by 谷歌翻译
Three main points: 1. Data Science (DS) will be increasingly important to heliophysics; 2. Methods of heliophysics science discovery will continually evolve, requiring the use of learning technologies [e.g., machine learning (ML)] that are applied rigorously and that are capable of supporting discovery; and 3. To grow with the pace of data, technology, and workforce changes, heliophysics requires a new approach to the representation of knowledge.
translated by 谷歌翻译
We describe a Physics-Informed Neural Network (PINN) that simulates the flow induced by the astronomical tide in a synthetic port channel, with dimensions based on the Santos - S\~ao Vicente - Bertioga Estuarine System. PINN models aim to combine the knowledge of physical systems and data-driven machine learning models. This is done by training a neural network to minimize the residuals of the governing equations in sample points. In this work, our flow is governed by the Navier-Stokes equations with some approximations. There are two main novelties in this paper. First, we design our model to assume that the flow is periodic in time, which is not feasible in conventional simulation methods. Second, we evaluate the benefit of resampling the function evaluation points during training, which has a near zero computational cost and has been verified to improve the final model, especially for small batch sizes. Finally, we discuss some limitations of the approximations used in the Navier-Stokes equations regarding the modeling of turbulence and how it interacts with PINNs.
translated by 谷歌翻译
The selection of an optimal pacing site, which is ideally scar-free and late activated, is critical to the response of cardiac resynchronization therapy (CRT). Despite the success of current approaches formulating the detection of such late mechanical activation (LMA) regions as a problem of activation time regression, their accuracy remains unsatisfactory, particularly in cases where myocardial scar exists. To address this issue, this paper introduces a multi-task deep learning framework that simultaneously estimates LMA amount and classify the scar-free LMA regions based on cine displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI). With a newly introduced auxiliary LMA region classification sub-network, our proposed model shows more robustness to the complex pattern cause by myocardial scar, significantly eliminates their negative effects in LMA detection, and in turn improves the performance of scar classification. To evaluate the effectiveness of our method, we tests our model on real cardiac MR images and compare the predicted LMA with the state-of-the-art approaches. It shows that our approach achieves substantially increased accuracy. In addition, we employ the gradient-weighted class activation mapping (Grad-CAM) to visualize the feature maps learned by all methods. Experimental results suggest that our proposed model better recognizes the LMA region pattern.
translated by 谷歌翻译
Artificial Intelligence (AI) is having a tremendous impact across most areas of science. Applications of AI in healthcare have the potential to improve our ability to detect, diagnose, prognose, and intervene on human disease. For AI models to be used clinically, they need to be made safe, reproducible and robust, and the underlying software framework must be aware of the particularities (e.g. geometry, physiology, physics) of medical data being processed. This work introduces MONAI, a freely available, community-supported, and consortium-led PyTorch-based framework for deep learning in healthcare. MONAI extends PyTorch to support medical data, with a particular focus on imaging, and provide purpose-specific AI model architectures, transformations and utilities that streamline the development and deployment of medical AI models. MONAI follows best practices for software-development, providing an easy-to-use, robust, well-documented, and well-tested software framework. MONAI preserves the simple, additive, and compositional approach of its underlying PyTorch libraries. MONAI is being used by and receiving contributions from research, clinical and industrial teams from around the world, who are pursuing applications spanning nearly every aspect of healthcare.
translated by 谷歌翻译
我们提供了奖励黑客的第一个正式定义,即优化不完美的代理奖励功能的现象,$ \ Mathcal {\ tilde {r}} $,根据真实的奖励功能,$ \ MATHCAL {R} $导致性能差。 。我们说,如果增加预期的代理回报率永远无法减少预期的真实回报,则代理是不可接受的。直觉上,可以通过从奖励功能(使其“较窄”)中留出一些术语或忽略大致等效的结果之间的细粒度区分来创建一个不可接受的代理,但是我们表明情况通常不是这样。一个关键的见解是,奖励的线性性(在州行动访问计数中)使得无法实现的状况非常强烈。特别是,对于所有随机策略的集合,只有在其中一个是恒定的,只有两个奖励函数才能是不可接受的。因此,我们将注意力转移到确定性的政策和有限的随机政策集中,在这些策略中,始终存在非平凡的不可动摇的对,并为简化的存在建立必要和充分的条件,这是一个重要的不被限制的特殊情况。我们的结果揭示了使用奖励函数指定狭窄任务和对齐人类价值的AI系统之间的紧张关系。
translated by 谷歌翻译