Methods based on ordinary differential equations (ODEs) are widely used to build generative models of time-series. In addition to high computational overhead due to explicitly computing hidden states recurrence, existing ODE-based models fall short in learning sequence data with sharp transitions - common in many real-world systems - due to numerical challenges during optimization. In this work, we propose LS4, a generative model for sequences with latent variables evolving according to a state space ODE to increase modeling capacity. Inspired by recent deep state space models (S4), we achieve speedups by leveraging a convolutional representation of LS4 which bypasses the explicit evaluation of hidden states. We show that LS4 significantly outperforms previous continuous-time generative models in terms of marginal distribution, classification, and prediction scores on real-world datasets in the Monash Forecasting Repository, and is capable of modeling highly stochastic data with sharp temporal transitions. LS4 sets state-of-the-art for continuous-time latent generative models, with significant improvement of mean squared error and tighter variational lower bounds on irregularly-sampled datasets, while also being x100 faster than other baselines on long sequences.

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

促使模型表现出令人印象深刻的几次学习能力。在测试时间与单个模型或多个模型的组成一起重复相互作用，进一步扩展了功能。这些组成是概率模型，可以用具有随机变量的图形模型的语言表示，其值是复杂的数据类型，例如字符串。具有控制流和动态结构的情况需要概率编程的技术，这些技术允许以统一语言实施不同的模型结构和推理策略。我们从这个角度正式化了几种现有技术，包括刮擦板 /思想链，验证者，星星，选择 - 推动和工具使用。我们将结果程序称为语言模型级联。

对网络规模数据进行培训可能需要几个月的时间。但是，在已经学习或不可学习的冗余和嘈杂点上浪费了很多计算和时间。为了加速训练，我们引入了可减少的持有损失选择（Rho-loss），这是一种简单但原则上的技术，它大致选择了这些训练点，最大程度地减少了模型的概括损失。结果，Rho-loss减轻了现有数据选择方法的弱点：优化文献中的技术通常选择“硬损失”（例如，高损失），但是这种点通常是嘈杂的（不可学习）或更少的任务与任务相关。相反，课程学习优先考虑“简单”的积分，但是一旦学习，就不必对这些要点进行培训。相比之下，Rho-Loss选择了可以学习的点，值得学习的，尚未学习。与先前的艺术相比，Rho-loss火车的步骤要少得多，可以提高准确性，并加快对广泛的数据集，超参数和体系结构（MLP，CNNS和BERT）的培训。在大型Web绑带图像数据集服装1M上，与统一的数据改组相比，步骤少18倍，最终精度的速度少2％。

Context-aware decision support in the operating room can foster surgical safety and efficiency by leveraging real-time feedback from surgical workflow analysis. Most existing works recognize surgical activities at a coarse-grained level, such as phases, steps or events, leaving out fine-grained interaction details about the surgical activity; yet those are needed for more helpful AI assistance in the operating room. Recognizing surgical actions as triplets of <instrument, verb, target> combination delivers comprehensive details about the activities taking place in surgical videos. This paper presents CholecTriplet2021: an endoscopic vision challenge organized at MICCAI 2021 for the recognition of surgical action triplets in laparoscopic videos. The challenge granted private access to the large-scale CholecT50 dataset, which is annotated with action triplet information. In this paper, we present the challenge setup and assessment of the state-of-the-art deep learning methods proposed by the participants during the challenge. A total of 4 baseline methods from the challenge organizers and 19 new deep learning algorithms by competing teams are presented to recognize surgical action triplets directly from surgical videos, achieving mean average precision (mAP) ranging from 4.2% to 38.1%. This study also analyzes the significance of the results obtained by the presented approaches, performs a thorough methodological comparison between them, in-depth result analysis, and proposes a novel ensemble method for enhanced recognition. Our analysis shows that surgical workflow analysis is not yet solved, and also highlights interesting directions for future research on fine-grained surgical activity recognition which is of utmost importance for the development of AI in surgery.

我们介绍了嘈杂的特征混音（NFM），这是一个廉价但有效的数据增强方法，这些方法结合了基于插值的训练和噪声注入方案。不是用凸面的示例和它们的标签的凸面组合训练，而不是在输入和特征空间中使用对数据点对的噪声扰动凸组合。该方法包括混合和歧管混合作为特殊情况，但它具有额外的优点，包括更好地平滑决策边界并实现改进的模型鲁棒性。我们提供理论要理解这一点以及NFM的隐式正则化效果。与混合和歧管混合相比，我们的理论得到了经验结果的支持，展示了NFM的优势。我们表明，在一系列计算机视觉基准数据集中，使用NFM培训的剩余网络和视觉变压器在清洁数据的预测准确性和鲁棒性之间具有有利的权衡。

我们介绍了Goldilocks Selection，这是一种用于更快的模型训练的技术，该技术选择了一系列“恰到好处”的训练点。我们提出了一个信息理论采集函数 - 可还原验证损失 - 并使用小的代理模型-GoldiProx进行计算，以有效地选择培训点，以最大程度地提高有关验证集的信息。我们表明，通常在优化文献中选择的“硬”（例如高损失）点通常是嘈杂的，而“简单”（例如低噪声）样本通常优先考虑课程学习提供更少的信息。此外，具有不确定标签的点（通常是由主动学习的目标）往往与任务相关。相比之下，Goldilocks选择选择了“恰到好处”的点，并且从经验上优于上述方法。此外，选定的序列可以转移到其他体系结构。从业者可以共享并重复使用它，而无需重新创建它。

$ t_ {1 \ rho} $映射是一种有希望的定量MRI技术，用于对组织性质的非侵入性评估。基于学习的方法可以从减少数量的$ t_ {1 \ rho} $加权图像中映射$ t_ {1 \ rho} $，但需要大量的高质量培训数据。此外，现有方法不提供$ t_ {1 \ rho} $估计的置信度。为了解决这些问题，我们提出了一个自我监督的学习神经网络，该网络使用学习过程中的放松约束来学习$ t_ {1 \ rho} $映射。为$ t_ {1 \ rho} $量化网络建立了认知不确定性和态度不确定性，以提供$ t_ {1 \ rho} $映射的贝叶斯置信度估计。不确定性估计还可以使模型规范化，以防止其学习不完美的数据。我们对52例非酒精性脂肪肝病患者收集的$ T_ {1 \ rho} $数据进行了实验。结果表明，我们的方法优于$ t_ {1 \ rho} $量化肝脏的现有方法，使用少于两个$ t_ {1 \ rho} $加权图像。我们的不确定性估计提供了一种可行的方法，可以建模基于自我监督学习的$ t_ {1 \ rho} $估计的信心，这与肝脏中的现实$ t_ {1 \ rho} $成像是一致的。

Few Shot Instance Segmentation (FSIS) requires models to detect and segment novel classes with limited several support examples. In this work, we explore a simple yet unified solution for FSIS as well as its incremental variants, and introduce a new framework named Reference Twice (RefT) to fully explore the relationship between support/query features based on a Transformer-like framework. Our key insights are two folds: Firstly, with the aid of support masks, we can generate dynamic class centers more appropriately to re-weight query features. Secondly, we find that support object queries have already encoded key factors after base training. In this way, the query features can be enhanced twice from two aspects, i.e., feature-level and instance-level. In particular, we firstly design a mask-based dynamic weighting module to enhance support features and then propose to link object queries for better calibration via cross-attention. After the above steps, the novel classes can be improved significantly over our strong baseline. Additionally, our new framework can be easily extended to incremental FSIS with minor modification. When benchmarking results on the COCO dataset for FSIS, gFSIS, and iFSIS settings, our method achieves a competitive performance compared to existing approaches across different shots, e.g., we boost nAP by noticeable +8.2/+9.4 over the current state-of-the-art FSIS method for 10/30-shot. We further demonstrate the superiority of our approach on Few Shot Object Detection. Code and model will be available.

In this chapter, we review and discuss the transformation of AI technology in HCI/UX work and assess how AI technology will change how we do the work. We first discuss how AI can be used to enhance the result of user research and design evaluation. We then discuss how AI technology can be used to enhance HCI/UX design. Finally, we discuss how AI-enabled capabilities can improve UX when users interact with computing systems, applications, and services.