Recent CLIP-guided 3D optimization methods, e.g., DreamFields and PureCLIPNeRF achieve great success in zero-shot text-guided 3D synthesis. However, due to the scratch training and random initialization without any prior knowledge, these methods usually fail to generate accurate and faithful 3D structures that conform to the corresponding text. In this paper, we make the first attempt to introduce the explicit 3D shape prior to CLIP-guided 3D optimization methods. Specifically, we first generate a high-quality 3D shape from input texts in the text-to-shape stage as the 3D shape prior. We then utilize it as the initialization of a neural radiance field and then optimize it with the full prompt. For the text-to-shape generation, we present a simple yet effective approach that directly bridges the text and image modalities with a powerful text-to-image diffusion model. To narrow the style domain gap between images synthesized by the text-to-image model and shape renderings used to train the image-to-shape generator, we further propose to jointly optimize a learnable text prompt and fine-tune the text-to-image diffusion model for rendering-style image generation. Our method, namely, Dream3D, is capable of generating imaginative 3D content with better visual quality and shape accuracy than state-of-the-art methods.

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.

高密度物体（例如金属植入物和牙科填充物）的存在可以在计算机断层扫描（CT）图像中引入严重的条纹样伪像，从而极大地限制了随后的诊断。尽管已经提出了用于减少金属伪像的各种基于神经网络的方法（MAR），但由于对正式域中的全球环境的利用有限，图像域引入的次生伪像，它们的性能通常不佳，并且需要精确的次要伪像。金属面具。为了解决这些问题，本文探讨了在辛图和图像域中在MAR中的快速傅立叶卷积，并提出了MAR的傅立叶双域网络，称为FD-MAR。具体而言，我们首先提出了一个傅立叶曲调恢复网络，该网络可以利用辛克图范围内的接受环境来填充来自未腐败区域的金属腐败区域，因此对金属痕迹是可靠的。其次，我们在图像域中提出了一个傅立叶细化网络，该网络可以通过探索整个图像范围的上下文信息以局部到全球的方式来完善重建的图像。结果，拟议的FD-MAR可以探索MAR的正式和图像范围的接收场。通过通过复合损失函数优化FD-MAR，广泛的实验结果证明了拟议的FD-MAR在定量指标和视觉比较方面的优越性优于最先进的MAR方法。值得注意的是，FD-MAR不需要精确的金属口罩，这在临床常规中非常重要。

我们提出了一种新方法，可以在2D超声心动图图像上自动轮廓左心室。与大多数基于预测细分面罩的现有分割方法不同，我们重点是预测该轮廓内（基础和顶点）中的心内膜轮廓和关键地标点。这提供了一种更接近专家如何执行手动注释的表示，因此产生了在生理上更合理的结果。我们提出的方法使用基于U-NET体系结构的两头网络。一个头预测了7个轮廓点，另一个头部预测了轮廓的距离图。将这种方法与U-NET和基于点的方法进行了比较，在具有里程碑意义的定位（<4.5mm）和与地面真相轮廓（<3.5mm）的距离方面，达到30 \％的性能增长。

本文介绍了一个新型的预训练的空间时间多对一（p-STMO）模型，用于2D到3D人类姿势估计任务。为了减少捕获空间和时间信息的困难，我们将此任务分为两个阶段：预训练（I期）和微调（II阶段）。在第一阶段，提出了一个自我监督的预训练子任务，称为蒙面姿势建模。输入序列中的人关节在空间和时间域中随机掩盖。利用denoising自动编码器的一般形式以恢复原始的2D姿势，并且编码器能够以这种方式捕获空间和时间依赖性。在第二阶段，将预训练的编码器加载到STMO模型并进行微调。编码器之后是一个多对一的框架聚合器，以预测当前帧中的3D姿势。尤其是，MLP块被用作STMO中的空间特征提取器，其性能比其他方法更好。此外，提出了一种时间下采样策略，以减少数据冗余。在两个基准上进行的广泛实验表明，我们的方法优于较少参数和较少计算开销的最先进方法。例如，我们的P-STMO模型在使用CPN作为输入的2D姿势时，在Human3.6M数据集上达到42.1mm MPJPE。同时，它为最新方法带来了1.5-7.1倍的速度。代码可在https://github.com/patrick-swk/p-stmo上找到。

自然语言理解（NLU）模型倾向于依靠虚假的相关性（即数据集偏见）来在分布数据集上实现高性能，但在分布外部的数据集中的性能差。大多数现有的偏见方法通常都以偏见的特征（即引起这种虚假相关性的表面特征）来识别和削弱这些样品。但是，下降加权这些样品阻碍了从这些样品的无偏见部分学习的模型。为了应对这一挑战，在本文中，我们建议从特征空间的角度以细粒度的方式消除虚假的相关性。具体而言，我们引入了随机傅立叶特征和加权重采样，以将功能之间的依赖关系解释以减轻虚假相关性。在获得非相关的功能后，我们进一步设计了一种基于相互信息的方法来净化它们，这迫使模型学习与任务更相关的功能。对两个经过良好研究的NLU任务进行的广泛实验表明，我们的方法优于其他比较方法。

从测试阶段的单个初始示例跟踪视觉对象已被广泛地作为一个/几次射击问题，即初始适应的一次性学习和在线适应的少量学习。近期几次拍摄的在线适应方法通过在离线阶段的复杂元学习优化中，从大量注释的训练数据中纳入了现有知识。这有助于在线深度跟踪器实现快速适应并降低跟踪的过度风险。在本文中，我们提出了一个简单但有效的递归最小二乘估计估计者辅助在线学习方法，但在不需要离线培训的情况下进行了几次拍摄的在线适应。它允许内置的内存保留机制进行模型，以记住关于之前看到的对象的知识，因此可以安全地从训练中安全地移除所看到的数据。这也与在防止灾难性遗忘的新出现的连续学习领域带有某些相似之处。这种机制使我们能够揭示现代在线深度跟踪器的力量，而不会产生过多的计算成本。我们根据在线学习家庭中的两个网络评估我们的方法，即在RT-MDNET中的多层的rceptrons和DIMP中的卷积神经网络。对若干具有挑战性的跟踪基准的一致性改进展示了其有效性和效率。

In this paper, we study the problem of knowledge-intensive text-to-SQL, in which domain knowledge is necessary to parse expert questions into SQL queries over domain-specific tables. We formalize this scenario by building a new Chinese benchmark KnowSQL consisting of domain-specific questions covering various domains. We then address this problem by presenting formulaic knowledge, rather than by annotating additional data examples. More concretely, we construct a formulaic knowledge bank as a domain knowledge base and propose a framework (ReGrouP) to leverage this formulaic knowledge during parsing. Experiments using ReGrouP demonstrate a significant 28.2% improvement overall on KnowSQL.

Weakly-supervised object localization aims to indicate the category as well as the scope of an object in an image given only the image-level labels. Most of the existing works are based on Class Activation Mapping (CAM) and endeavor to enlarge the discriminative area inside the activation map to perceive the whole object, yet ignore the co-occurrence confounder of the object and context (e.g., fish and water), which makes the model inspection hard to distinguish object boundaries. Besides, the use of CAM also brings a dilemma problem that the classification and localization always suffer from a performance gap and can not reach their highest accuracy simultaneously. In this paper, we propose a casual knowledge distillation method, dubbed KD-CI-CAM, to address these two under-explored issues in one go. More specifically, we tackle the co-occurrence context confounder problem via causal intervention (CI), which explores the causalities among image features, contexts, and categories to eliminate the biased object-context entanglement in the class activation maps. Based on the de-biased object feature, we additionally propose a multi-teacher causal distillation framework to balance the absorption of classification knowledge and localization knowledge during model training. Extensive experiments on several benchmarks demonstrate the effectiveness of KD-CI-CAM in learning clear object boundaries from confounding contexts and addressing the dilemma problem between classification and localization performance.

Dynamic treatment regimes assign personalized treatments to patients sequentially over time based on their baseline information and time-varying covariates. In mobile health applications, these covariates are typically collected at different frequencies over a long time horizon. In this paper, we propose a deep spectral Q-learning algorithm, which integrates principal component analysis (PCA) with deep Q-learning to handle the mixed frequency data. In theory, we prove that the mean return under the estimated optimal policy converges to that under the optimal one and establish its rate of convergence. The usefulness of our proposal is further illustrated via simulations and an application to a diabetes dataset.