超声检查广泛用于甲状腺结节（良性/恶性）的临床诊断。但是，准确性在很大程度上取决于放射科医生的经验。尽管已经研究了甲状腺结节识别的深度学习技术。当前的解决方案主要基于静态超声图像，其时间信息有限，并且与临床诊断不一致。本文提出了一种通过详尽的超声视频和钥匙框架进行详尽的探索来自动识别甲状腺结节的新方法。我们首先提出一个检测 - 定位框架，以自动识别每个超声视频中典型结节的临床密钥框架。根据本地化的键框架，我们为甲状腺结节识别开发了一个钥匙框引导的视频分类模型。此外，我们引入了运动注意模块，以帮助网络关注超声视频中的重要帧，这与临床诊断一致。拟议的甲状腺结节识别框架已在临床收集的超声视频上进行了验证，与其他最先进的方法相比，表现出卓越的性能。

由于其简单性和实用性，密度峰值聚类已成为聚类算法的NOVA。但是，这是一个主要的缺点：由于其高计算复杂性，这是耗时的。在此，开发了稀疏搜索和K-D树的密度峰聚类算法来解决此问题。首先，通过使用k-d树来替换原始的全等级距离矩阵来计算稀疏距离矩阵，以加速局部密度的计算。其次，提出了一种稀疏的搜索策略，以加快与$ k $最近邻居的集合与由数据点组成的集合之间的相互分离的计算。此外，采用了决策值的二阶差异方法来自适应确定群集中心。最后，通过与其他六种最先进的聚类算法进行比较，在具有不同分布特性的数据集上进行实验。事实证明，该算法可以有效地将原始DPC的计算复杂性从$ O（n^2k）$降低到$ O（n（n^{1-1/k}+k））$。特别是对于较大的数据集，效率更加明显地提高。此外，聚类精度也在一定程度上提高了。因此，可以得出结论，新提出的算法的总体性能非常好。

近年来，神经网络在各个领域中表现出强大的力量，它也带来了越来越多的安全威胁。基于神经网络模型的STEGOMALWARE是代表性的。以前的研究初步证明通过突出神经网络模型中的恶意软件来启动恶意攻击的可行性。然而，现有的作品没有表明，由于恶意软件嵌入率低，模型性能降低以及额外的努力，这种新兴威胁在现实世界攻击中是实际的攻击。因此，我们预测一个称为evilmodel的改进的斯佩塔科。在分析神经网络模型的结构的基础上，我们将二进制形成恶意软件作为其参数嵌入神经网络模型，并提出了三种新的恶意软件嵌入技术，即MSB保留，快速替换和半替换。通过结婚19个恶意软件样本和10个流行的神经网络模型，我们构建了550个恶意软件嵌入式模型，并在想象中数据集中分析了这些模型的性能。实验结果表明，半取代几乎完美地表现出，恶意软件嵌入率为48.52％，没有模型性能下降或额外的努力。考虑到一系列因素，我们提出了一种定量算法来评估不同的嵌入方法。评估结果表明，邪恶的模型与经典的斯托图尼特有多高。此外，我们开展案例研究，以触发真实世界的情景中的邪恶模型。要深入了解所提出的恶意软件嵌入技术，我们还研究了神经网络结构，层和参数大小对恶意软件嵌入容量和嵌入式模型精度的影响。我们还提供了一些可能的对策来捍卫邪恶的模型。我们希望这项工作能够全面了解这种新的AI动力威胁，并建议提前辩护。

命令和控制（C＆C）在攻击中很重要。它将命令从攻击者传输到受损的主机中的恶意软件。目前，一些攻击者在C＆C任务中使用在线社交网络（OSN）。 OSN的C＆C中有两个主要问题。首先，恶意软件找到攻击者的过程是可逆的。如果防御者分析了恶意软件样本，则在发布命令之前将暴露攻击者。其次，以普通或加密形式的命令被OSN视为异常内容，这会引起异常并触发攻击者的限制。防御者暴露后可以限制攻击者。在这项工作中，我们建议在OSN上使用AI驱动的C＆C DEEPC2来解决这些问题。对于可逆的硬编码，恶意软件使用神经网络模型找到了攻击者。攻击者的头像被转换为​​一批特征向量，并且防御者无法使用模型和特征向量提前恢复头像。为了求解OSN上的异常内容，哈希碰撞和文本数据扩展用于将命令嵌入正常内容中。 Twitter上的实验表明，可以有效地生成命令包裹的推文。恶意软件可以在OSN上秘密地找到攻击者。安全分析表明，很难提前恢复攻击者的标识符。

A recent study has shown a phenomenon called neural collapse in that the within-class means of features and the classifier weight vectors converge to the vertices of a simplex equiangular tight frame at the terminal phase of training for classification. In this paper, we explore the corresponding structures of the last-layer feature centers and classifiers in semantic segmentation. Based on our empirical and theoretical analysis, we point out that semantic segmentation naturally brings contextual correlation and imbalanced distribution among classes, which breaks the equiangular and maximally separated structure of neural collapse for both feature centers and classifiers. However, such a symmetric structure is beneficial to discrimination for the minor classes. To preserve these advantages, we introduce a regularizer on feature centers to encourage the network to learn features closer to the appealing structure in imbalanced semantic segmentation. Experimental results show that our method can bring significant improvements on both 2D and 3D semantic segmentation benchmarks. Moreover, our method ranks 1st and sets a new record (+6.8% mIoU) on the ScanNet200 test leaderboard. Code will be available at https://github.com/dvlab-research/Imbalanced-Learning.

When using LiDAR semantic segmentation models for safety-critical applications such as autonomous driving, it is essential to understand and improve their robustness with respect to a large range of LiDAR corruptions. In this paper, we aim to comprehensively analyze the robustness of LiDAR semantic segmentation models under various corruptions. To rigorously evaluate the robustness and generalizability of current approaches, we propose a new benchmark called SemanticKITTI-C, which features 16 out-of-domain LiDAR corruptions in three groups, namely adverse weather, measurement noise and cross-device discrepancy. Then, we systematically investigate 11 LiDAR semantic segmentation models, especially spanning different input representations (e.g., point clouds, voxels, projected images, and etc.), network architectures and training schemes. Through this study, we obtain two insights: 1) We find out that the input representation plays a crucial role in robustness. Specifically, under specific corruptions, different representations perform variously. 2) Although state-of-the-art methods on LiDAR semantic segmentation achieve promising results on clean data, they are less robust when dealing with noisy data. Finally, based on the above observations, we design a robust LiDAR segmentation model (RLSeg) which greatly boosts the robustness with simple but effective modifications. It is promising that our benchmark, comprehensive analysis, and observations can boost future research in robust LiDAR semantic segmentation for safety-critical applications.

In contrast to the control-theoretic methods, the lack of stability guarantee remains a significant problem for model-free reinforcement learning (RL) methods. Jointly learning a policy and a Lyapunov function has recently become a promising approach to ensuring the whole system with a stability guarantee. However, the classical Lyapunov constraints researchers introduced cannot stabilize the system during the sampling-based optimization. Therefore, we propose the Adaptive Stability Certification (ASC), making the system reach sampling-based stability. Because the ASC condition can search for the optimal policy heuristically, we design the Adaptive Lyapunov-based Actor-Critic (ALAC) algorithm based on the ASC condition. Meanwhile, our algorithm avoids the optimization problem that a variety of constraints are coupled into the objective in current approaches. When evaluated on ten robotic tasks, our method achieves lower accumulated cost and fewer stability constraint violations than previous studies.

A storyboard is a roadmap for video creation which consists of shot-by-shot images to visualize key plots in a text synopsis. Creating video storyboards however remains challenging which not only requires association between high-level texts and images, but also demands for long-term reasoning to make transitions smooth across shots. In this paper, we propose a new task called Text synopsis to Video Storyboard (TeViS) which aims to retrieve an ordered sequence of images to visualize the text synopsis. We construct a MovieNet-TeViS benchmark based on the public MovieNet dataset. It contains 10K text synopses each paired with keyframes that are manually selected from corresponding movies by considering both relevance and cinematic coherence. We also present an encoder-decoder baseline for the task. The model uses a pretrained vision-and-language model to improve high-level text-image matching. To improve coherence in long-term shots, we further propose to pre-train the decoder on large-scale movie frames without text. Experimental results demonstrate that our proposed model significantly outperforms other models to create text-relevant and coherent storyboards. Nevertheless, there is still a large gap compared to human performance suggesting room for promising future work.

Denoising Diffusion Probabilistic Models (DDPMs) are emerging in text-to-speech (TTS) synthesis because of their strong capability of generating high-fidelity samples. However, their iterative refinement process in high-dimensional data space results in slow inference speed, which restricts their application in real-time systems. Previous works have explored speeding up by minimizing the number of inference steps but at the cost of sample quality. In this work, to improve the inference speed for DDPM-based TTS model while achieving high sample quality, we propose ResGrad, a lightweight diffusion model which learns to refine the output spectrogram of an existing TTS model (e.g., FastSpeech 2) by predicting the residual between the model output and the corresponding ground-truth speech. ResGrad has several advantages: 1) Compare with other acceleration methods for DDPM which need to synthesize speech from scratch, ResGrad reduces the complexity of task by changing the generation target from ground-truth mel-spectrogram to the residual, resulting into a more lightweight model and thus a smaller real-time factor. 2) ResGrad is employed in the inference process of the existing TTS model in a plug-and-play way, without re-training this model. We verify ResGrad on the single-speaker dataset LJSpeech and two more challenging datasets with multiple speakers (LibriTTS) and high sampling rate (VCTK). Experimental results show that in comparison with other speed-up methods of DDPMs: 1) ResGrad achieves better sample quality with the same inference speed measured by real-time factor; 2) with similar speech quality, ResGrad synthesizes speech faster than baseline methods by more than 10 times. Audio samples are available at https://resgrad1.github.io/.

Retrieval-augmented in-context learning has emerged as a powerful approach for addressing knowledge-intensive tasks using frozen language models (LM) and retrieval models (RM). Existing work has combined these in simple "retrieve-then-read" pipelines in which the RM retrieves passages that are inserted into the LM prompt. To begin to fully realize the potential of frozen LMs and RMs, we propose Demonstrate-Search-Predict (DSP), a framework that relies on passing natural language texts in sophisticated pipelines between an LM and an RM. DSP can express high-level programs that bootstrap pipeline-aware demonstrations, search for relevant passages, and generate grounded predictions, systematically breaking down problems into small transformations that the LM and RM can handle more reliably. We have written novel DSP programs for answering questions in open-domain, multi-hop, and conversational settings, establishing in early evaluations new state-of-the-art in-context learning results and delivering 37-200%, 8-40%, and 80-290% relative gains against vanilla LMs, a standard retrieve-then-read pipeline, and a contemporaneous self-ask pipeline, respectively.