We propose a new causal inference framework to learn causal effects from multiple, decentralized data sources in a federated setting. We introduce an adaptive transfer algorithm that learns the similarities among the data sources by utilizing Random Fourier Features to disentangle the loss function into multiple components, each of which is associated with a data source. The data sources may have different distributions; the causal effects are independently and systematically incorporated. The proposed method estimates the similarities among the sources through transfer coefficients, and hence requiring no prior information about the similarity measures. The heterogeneous causal effects can be estimated with no sharing of the raw training data among the sources, thus minimizing the risk of privacy leak. We also provide minimax lower bounds to assess the quality of the parameters learned from the disparate sources. The proposed method is empirically shown to outperform the baselines on decentralized data sources with dissimilar distributions.

In optimization-based approaches to inverse problems and to statistical estimation, it is common to augment the objective with a regularizer to address challenges associated with ill-posedness. The choice of a suitable regularizer is typically driven by prior domain information and computational considerations. Convex regularizers are attractive as they are endowed with certificates of optimality as well as the toolkit of convex analysis, but exhibit a computational scaling that makes them ill-suited beyond moderate-sized problem instances. On the other hand, nonconvex regularizers can often be deployed at scale, but do not enjoy the certification properties associated with convex regularizers. In this paper, we seek a systematic understanding of the power and the limitations of convex regularization by investigating the following questions: Given a distribution, what are the optimal regularizers, both convex and nonconvex, for data drawn from the distribution? What properties of a data source govern whether it is amenable to convex regularization? We address these questions for the class of continuous and positively homogenous regularizers for which convex and nonconvex regularizers correspond, respectively, to convex bodies and star bodies. By leveraging dual Brunn-Minkowski theory, we show that a radial function derived from a data distribution is the key quantity for identifying optimal regularizers and for assessing the amenability of a data source to convex regularization. Using tools such as $\Gamma$-convergence, we show that our results are robust in the sense that the optimal regularizers for a sample drawn from a distribution converge to their population counterparts as the sample size grows large. Finally, we give generalization guarantees that recover previous results for polyhedral regularizers (i.e., dictionary learning) and lead to new ones for semidefinite regularizers.

Automatic segmentation of kidney and kidney tumour in Computed Tomography (CT) images is essential, as it uses less time as compared to the current gold standard of manual segmentation. However, many hospitals are still reliant on manual study and segmentation of CT images by medical practitioners because of its higher accuracy. Thus, this study focuses on the development of an approach for automatic kidney and kidney tumour segmentation in contrast-enhanced CT images. A method based on Convolutional Neural Network (CNN) was proposed, where a 3D U-Net segmentation model was developed and trained to delineate the kidney and kidney tumour from CT scans. Each CT image was pre-processed before inputting to the CNN, and the effect of down-sampled and patch-wise input images on the model performance was analysed. The proposed method was evaluated on the publicly available 2021 Kidney and Kidney Tumour Segmentation Challenge (KiTS21) dataset. The method with the best performing model recorded an average training Dice score of 0.6129, with the kidney and kidney tumour Dice scores of 0.7923 and 0.4344, respectively. For testing, the model obtained a kidney Dice score of 0.8034, and a kidney tumour Dice score of 0.4713, with an average Dice score of 0.6374.

The Coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, in early December 2019 and now becoming a pandemic. When COVID-19 patients undergo radiography examination, radiologists can observe the present of radiographic abnormalities from their chest X-ray (CXR) images. In this study, a deep convolutional neural network (CNN) model was proposed to aid radiologists in diagnosing COVID-19 patients. First, this work conducted a comparative study on the performance of modified VGG-16, ResNet-50 and DenseNet-121 to classify CXR images into normal, COVID-19 and viral pneumonia. Then, the impact of image augmentation on the classification results was evaluated. The publicly available COVID-19 Radiography Database was used throughout this study. After comparison, ResNet-50 achieved the highest accuracy with 95.88%. Next, after training ResNet-50 with rotation, translation, horizontal flip, intensity shift and zoom augmented dataset, the accuracy dropped to 80.95%. Furthermore, an ablation study on the effect of image augmentation on the classification results found that the combinations of rotation and intensity shift augmentation methods obtained an accuracy higher than baseline, which is 96.14%. Finally, ResNet-50 with rotation and intensity shift augmentations performed the best and was proposed as the final classification model in this work. These findings demonstrated that the proposed classification model can provide a promising result for COVID-19 diagnosis.

Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License.

With climate change predicted to increase the likelihood of landslide events, there is a growing need for rapid landslide detection technologies that help inform emergency responses. Synthetic Aperture Radar (SAR) is a remote sensing technique that can provide measurements of affected areas independent of weather or lighting conditions. Usage of SAR, however, is hindered by domain knowledge that is necessary for the pre-processing steps and its interpretation requires expert knowledge. We provide simplified, pre-processed, machine-learning ready SAR datacubes for four globally located landslide events obtained from several Sentinel-1 satellite passes before and after a landslide triggering event together with segmentation maps of the landslides. From this dataset, using the Hokkaido, Japan datacube, we study the feasibility of SAR-based landslide detection with supervised deep learning (DL). Our results demonstrate that DL models can be used to detect landslides from SAR data, achieving an Area under the Precision-Recall curve exceeding 0.7. We find that additional satellite visits enhance detection performance, but that early detection is possible when SAR data is combined with terrain information from a digital elevation model. This can be especially useful for time-critical emergency interventions. Code is made publicly available at https://github.com/iprapas/landslide-sar-unet.

学习在无人驾驶汽车（UAV）捕获的图像中检测物体（例如人类）通常会遭受无人机对物体的位置造成的巨大变化。此外，现有的基于无人机的基准数据集不提供足够的数据集元数据，这对于精确的模型诊断至关重要，并且学习功能不变。在本文中，我们介绍了大天使，这是第一个基于无人机的对象检测数据集，该数据集由具有相似想象条件以及无人机位置以及对象姿势元数据捕获的真实和合成子集组成。一系列实验经过精心设计，使用最先进的对象检测器设计，以证明在模型评估过程中利用元数据的好处。此外，还提供了几种涉及模型微调过程中涉及真实和合成数据的关键见解。最后，我们讨论了有关大天使的优势，局限性和未来方向，以突出其对更广泛的机器学习社区的独特价值。

基于视觉的机器人组装是一项至关重要但具有挑战性的任务，因为与多个对象的相互作用需要高水平的精度。在本文中，我们提出了一个集成的6D机器人系统，以感知，掌握，操纵和组装宽度，以紧密的公差。为了提供仅在现成的RGB解决方案的情况下，我们的系统建立在单眼6D对象姿势估计网络上，该估计网络仅使用合成图像训练，该图像利用了基于物理的渲染。随后，提出了姿势引导的6D转换以及无碰撞组装来构建具有任意初始姿势的任何设计结构。我们的新型3轴校准操作通过解开6D姿势估计和机器人组件进一步提高了精度和鲁棒性。定量和定性结果都证明了我们提出的6D机器人组装系统的有效性。

有效的视觉在延迟预算下的精度最大化。这些作品一次评估脱机准确性，一次是一张图像。但是，诸如自动驾驶之类的实时视觉应用在流媒体设置中运行，在这些设置中，地面真相在推理开始和终点之间会发生变化。这会导致明显的准确性下降。因此，最近提出的一项旨在最大程度地提高流媒体设置准确性的工作。在本文中，我们建议在每个环境环境中最大化流的准确性。我们认为场景难度会影响初始（离线）精度差异，而场景中的障碍物位移会影响后续的准确性降解。我们的方法章鱼使用这些方案属性来选择在测试时最大化流量准确性的配置。我们的方法将跟踪性能（S-MOTA）提高了7.4％，而常规静态方法则提高了。此外，使用我们的方法提高性能，而不是离线准确性的进步，而不是代替而不是进步。

细粒度的动作识别是计算机视觉中的一项具有挑战性的任务。由于细粒的数据集在空间和时间空间中具有较小的类间变化，因此细粒度的动作识别模型需要良好的时间推理和属性动作语义的歧视。利用CNN捕获高级时空特征表示能力以及变压器在捕获潜在语义和全球依赖性方面的建模效率，我们研究了两个结合CNN视觉骨干和变压器编码器以增强良好粒度动作识别的框架：1）基于编码器学习潜在的时间语义，以及2）多模式视频文本交叉编码器，以利用其他文本输入并学习视觉语义和文本语义之间的交叉关联。我们的实验结果表明，我们的变压器编码器框架有效地学习潜在的时间语义和跨模式关联，并且比CNN视觉模型改善了识别性能。我们在firgym基准数据集上实现了新的最先进的性能，用于两种拟议的架构。