无数据知识蒸馏(DFKD)最近引起了人们的关注,这要归功于其在不使用培训数据的情况下将知识从教师网络转移到学生网络的吸引力。主要思想是使用发电机合成数据以培训学生。随着发电机的更新,合成数据的分布将发生变化。如果发电机和学生接受对手的训练,使学生忘记了先前一步获得的知识,则这种分配转换可能会很大。为了减轻这个问题,我们提出了一种简单而有效的方法,称为动量对抗蒸馏(MAD),该方法维持了发电机的指数移动平均值(EMA)副本,并使用发电机和EMA生成器的合成样品来培训学生。由于EMA发电机可以被视为发电机旧版本的合奏,并且与发电机相比,更新的更改通常会发生较小的变化,因此对其合成样本进行培训可以帮助学生回顾过去的知识,并防止学生适应太快的速度发电机的新更新。我们在六个基准数据集上进行的实验,包括ImageNet和Place365,表明MAD的性能优于竞争方法来处理大型分配转移问题。我们的方法还与现有的DFKD方法相比,甚至在某些情况下达到了最新的方法。
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对基于深度学习的模型的对抗性攻击对当前的AI基础架构构成了重大威胁。其中,特洛伊木马袭击是最难防御的。在本文中,我们首先引入了Badnet类型的攻击变体,该攻击将特洛伊木马后门引入多个目标类,并允许将触发器放置在图像中的任何位置。前者使其更有效,后者使在物理空间中进行攻击变得非常容易。这种威胁模型的最先进的特洛伊木马检测方法失败了。为了防止这种攻击,我们首先引入了一种触发反向工程机制,该机制使用多个图像来恢复各种潜在的触发器。然后,我们通过测量此类恢复触发器的可传递性提出了检测机制。特洛伊木马触发器的可传递性将非常高,即它们使其他图像也进入同一类。我们研究攻击方法的许多实际优势,然后使用各种图像数据集证明检测性能。实验结果表明,我们方法的卓越检测性能超过了最新的。
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特洛伊木马对深度神经网络的攻击既危险又秘密。在过去的几年中,特洛伊木马的攻击从仅使用单个输入 - 不知不线的触发器和仅针对一个类别使用多个输入特异性触发器和定位多个类的类别。但是,特洛伊木马的防御尚未赶上这一发展。大多数防御方法仍然使对特洛伊木马触发器和目标类别的假设不足,因此,现代特洛伊木马的攻击很容易被规避。为了解决这个问题,我们提出了两种新颖的“过滤”防御措施,称为变分输入过滤(VIF)和对抗输入过滤(AIF),它们分别利用有损数据压缩和对抗性学习,以有效地纯化潜在的Trojan触发器,而无需在运行时间内触发潜在的Trojan触发器。对触发器/目标类的数量或触发器的输入依赖性属性做出假设。此外,我们还引入了一种称为“过滤 - 对抗性”(FTC)的新防御机制,该机制有助于避免通过“过滤”引起的清洁数据的分类准确性下降,并将其与VIF/AIF结合起来,从种类。广泛的实验结果和消融研究表明,我们提议的防御能力在减轻五次高级特洛伊木马攻击方面显着优于众所周知的基线防御能力,包括最近的两次最新一次,同时对少量训练数据和大型触发器非常强大。
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Q学习目标的乐观性质导致高度估计偏差,这是与标准$ Q-$学习相关的固有问题。这种偏差未能考虑低返回的可能性,特别是在风险方案中。然而,偏差的存在,无论是高估还是低估,不一定都不需要不可取。在本文中,我们分析了偏见学习的效用,并表明具体类型的偏差可能是优选的,这取决于场景。基于这一发现,我们设计了一种新颖的加强学习算法,平衡Q学习,其中将目标被修改为悲观和乐观术语的凸起组合,其相关权重分析地确定在线确定。我们在表格设置中证明了该算法的收敛,并经验证明了其在各种环境中的优越学习性能。
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We present 3D Highlighter, a technique for localizing semantic regions on a mesh using text as input. A key feature of our system is the ability to interpret "out-of-domain" localizations. Our system demonstrates the ability to reason about where to place non-obviously related concepts on an input 3D shape, such as adding clothing to a bare 3D animal model. Our method contextualizes the text description using a neural field and colors the corresponding region of the shape using a probability-weighted blend. Our neural optimization is guided by a pre-trained CLIP encoder, which bypasses the need for any 3D datasets or 3D annotations. Thus, 3D Highlighter is highly flexible, general, and capable of producing localizations on a myriad of input shapes. Our code is publicly available at https://github.com/threedle/3DHighlighter.
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We present a neural technique for learning to select a local sub-region around a point which can be used for mesh parameterization. The motivation for our framework is driven by interactive workflows used for decaling, texturing, or painting on surfaces. Our key idea is to incorporate segmentation probabilities as weights of a classical parameterization method, implemented as a novel differentiable parameterization layer within a neural network framework. We train a segmentation network to select 3D regions that are parameterized into 2D and penalized by the resulting distortion, giving rise to segmentations which are distortion-aware. Following training, a user can use our system to interactively select a point on the mesh and obtain a large, meaningful region around the selection which induces a low-distortion parameterization. Our code and project page are currently available.
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There is no settled universal 3D representation for geometry with many alternatives such as point clouds, meshes, implicit functions, and voxels to name a few. In this work, we present a new, compelling alternative for representing shapes using a sequence of cross-sectional closed loops. The loops across all planes form an organizational hierarchy which we leverage for autoregressive shape synthesis and editing. Loops are a non-local description of the underlying shape, as simple loop manipulations (such as shifts) result in significant structural changes to the geometry. This is in contrast to manipulating local primitives such as points in a point cloud or a triangle in a triangle mesh. We further demonstrate that loops are intuitive and natural primitive for analyzing and editing shapes, both computationally and for users.
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We propose RANA, a relightable and articulated neural avatar for the photorealistic synthesis of humans under arbitrary viewpoints, body poses, and lighting. We only require a short video clip of the person to create the avatar and assume no knowledge about the lighting environment. We present a novel framework to model humans while disentangling their geometry, texture, and also lighting environment from monocular RGB videos. To simplify this otherwise ill-posed task we first estimate the coarse geometry and texture of the person via SMPL+D model fitting and then learn an articulated neural representation for photorealistic image generation. RANA first generates the normal and albedo maps of the person in any given target body pose and then uses spherical harmonics lighting to generate the shaded image in the target lighting environment. We also propose to pretrain RANA using synthetic images and demonstrate that it leads to better disentanglement between geometry and texture while also improving robustness to novel body poses. Finally, we also present a new photorealistic synthetic dataset, Relighting Humans, to quantitatively evaluate the performance of the proposed approach.
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We propose a novel deep neural network architecture to learn interpretable representation for medical image analysis. Our architecture generates a global attention for region of interest, and then learns bag of words style deep feature embeddings with local attention. The global, and local feature maps are combined using a contemporary transformer architecture for highly accurate Gallbladder Cancer (GBC) detection from Ultrasound (USG) images. Our experiments indicate that the detection accuracy of our model beats even human radiologists, and advocates its use as the second reader for GBC diagnosis. Bag of words embeddings allow our model to be probed for generating interpretable explanations for GBC detection consistent with the ones reported in medical literature. We show that the proposed model not only helps understand decisions of neural network models but also aids in discovery of new visual features relevant to the diagnosis of GBC. Source-code and model will be available at https://github.com/sbasu276/RadFormer
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Machine learning is the study of computer algorithms that can automatically improve based on data and experience. Machine learning algorithms build a model from sample data, called training data, to make predictions or judgments without being explicitly programmed to do so. A variety of wellknown machine learning algorithms have been developed for use in the field of computer science to analyze data. This paper introduced a new machine learning algorithm called impact learning. Impact learning is a supervised learning algorithm that can be consolidated in both classification and regression problems. It can furthermore manifest its superiority in analyzing competitive data. This algorithm is remarkable for learning from the competitive situation and the competition comes from the effects of autonomous features. It is prepared by the impacts of the highlights from the intrinsic rate of natural increase (RNI). We, moreover, manifest the prevalence of the impact learning over the conventional machine learning algorithm.
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