神经辐射场(NERF)是一种普遍的视图综合技术,其表示作为连续体积函数的场景,由多层的感知来参数化,其提供每个位置处的体积密度和视图相关的发射辐射。虽然基于NERF的技术在代表精细的几何结构时,具有平稳变化的视图依赖性外观,但它们通常无法精确地捕获和再现光泽表面的外观。我们通过引入Ref-nerf来解决这些限制,该ref-nerf替换了nerf的视图依赖性输出辐射的参数化,使用反射辐射的表示和使用空间不同场景属性的集合来构造该函数的表示。我们展示了与正常载体上的规范器一起,我们的模型显着提高了镜面反射的现实主义和准确性。此外,我们表明我们的模型的外向光线的内部表示是可解释的,可用于场景编辑。
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We present a learned, spatially-varying steganography system that allows detecting when and how images have been altered by cropping, splicing or inpainting after publication. The system comprises a learned encoder that imperceptibly hides distinct positional signatures in every local image region before publication, and an accompanying learned decoder that extracts the steganographic signatures to determine, for each local image region, its 2D positional coordinates within the originally-published image. Crop and replacement edits become detectable by the inconsistencies they cause in the hidden positional signatures. Using a prototype system for small $(400 \times 400)$ images, we show experimentally that simple CNN encoder and decoder architectures can be trained jointly to achieve detection that is reliable and robust, without introducing perceptible distortion. This approach could help individuals and image-sharing platforms certify that an image was published by a trusted source, and also know which parts of such an image, if any, have been substantially altered since publication.
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我们介绍了一个自下而上的模型,用于同时在图像中找到许多边界元素,包括轮廓,角落和结。该模型在每个小贴片中使用包括M角度和自由移动顶点的“广义M-结”解释了每个小贴片中的边界形状。使用非凸优化进行分析图像,以在每个位置协同地发现M + 2个结值,其新颖的常规器强制强制执行,这些规则器在保持曲率的同时保持曲率和结。由此产生的“结区”同时是轮廓检测器,角/结检测器,以及区域外观的边界意识平滑。值得注意的是,其统一分析轮廓,角落,连接和均匀区域允许它在高噪声水平上成功,其中用于分割和边界检测的其他方法失败。
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我们提出了一种充分的条件,可以从平坦纹理过程的未知正交投影中恢复独特的纹理和观点。我们表明四个观察一般都足够了,我们表征了模糊的案件。结果适用于纹理和基于纹理的结构的形状。
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Migraine is a high-prevalence and disabling neurological disorder. However, information migraine management in real-world settings could be limited to traditional health information sources. In this paper, we (i) verify that there is substantial migraine-related chatter available on social media (Twitter and Reddit), self-reported by migraine sufferers; (ii) develop a platform-independent text classification system for automatically detecting self-reported migraine-related posts, and (iii) conduct analyses of the self-reported posts to assess the utility of social media for studying this problem. We manually annotated 5750 Twitter posts and 302 Reddit posts. Our system achieved an F1 score of 0.90 on Twitter and 0.93 on Reddit. Analysis of information posted by our 'migraine cohort' revealed the presence of a plethora of relevant information about migraine therapies and patient sentiments associated with them. Our study forms the foundation for conducting an in-depth analysis of migraine-related information using social media data.
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We present a method for controlling a swarm using its spectral decomposition -- that is, by describing the set of trajectories of a swarm in terms of a spatial distribution throughout the operational domain -- guaranteeing scale invariance with respect to the number of agents both for computation and for the operator tasked with controlling the swarm. We use ergodic control, decentralized across the network, for implementation. In the DARPA OFFSET program field setting, we test this interface design for the operator using the STOMP interface -- the same interface used by Raytheon BBN throughout the duration of the OFFSET program. In these tests, we demonstrate that our approach is scale-invariant -- the user specification does not depend on the number of agents; it is persistent -- the specification remains active until the user specifies a new command; and it is real-time -- the user can interact with and interrupt the swarm at any time. Moreover, we show that the spectral/ergodic specification of swarm behavior degrades gracefully as the number of agents goes down, enabling the operator to maintain the same approach as agents become disabled or are added to the network. We demonstrate the scale-invariance and dynamic response of our system in a field relevant simulator on a variety of tactical scenarios with up to 50 agents. We also demonstrate the dynamic response of our system in the field with a smaller team of agents. Lastly, we make the code for our system available.
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We develop a Bayesian semi-parametric model for the estimating the impact of dynamic treatment rules on survival among patients diagnosed with pediatric acute myeloid leukemia (AML). The data consist of a subset of patients enrolled in the phase III AAML1031 clinical trial in which patients move through a sequence of four treatment courses. At each course, they undergo treatment that may or may not include anthracyclines (ACT). While ACT is known to be effective at treating AML, it is also cardiotoxic and can lead to early death for some patients. Our task is to estimate the potential survival probability under hypothetical dynamic ACT treatment strategies, but there are several impediments. First, since ACT was not randomized in the trial, its effect on survival is confounded over time. Second, subjects initiate the next course depending on when they recover from the previous course, making timing potentially informative of subsequent treatment and survival. Third, patients may die or drop out before ever completing the full treatment sequence. We develop a generative Bayesian semi-parametric model based on Gamma Process priors to address these complexities. At each treatment course, the model captures subjects' transition to subsequent treatment or death in continuous time under a given rule. A g-computation procedure is used to compute a posterior over potential survival probability that is adjusted for time-varying confounding. Using this approach, we conduct posterior inference for the efficacy of hypothetical treatment rules that dynamically modify ACT based on evolving cardiac function.
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In computer-aided drug discovery (CADD), virtual screening (VS) is used for identifying the drug candidates that are most likely to bind to a molecular target in a large library of compounds. Most VS methods to date have focused on using canonical compound representations (e.g., SMILES strings, Morgan fingerprints) or generating alternative fingerprints of the compounds by training progressively more complex variational autoencoders (VAEs) and graph neural networks (GNNs). Although VAEs and GNNs led to significant improvements in VS performance, these methods suffer from reduced performance when scaling to large virtual compound datasets. The performance of these methods has shown only incremental improvements in the past few years. To address this problem, we developed a novel method using multiparameter persistence (MP) homology that produces topological fingerprints of the compounds as multidimensional vectors. Our primary contribution is framing the VS process as a new topology-based graph ranking problem by partitioning a compound into chemical substructures informed by the periodic properties of its atoms and extracting their persistent homology features at multiple resolution levels. We show that the margin loss fine-tuning of pretrained Triplet networks attains highly competitive results in differentiating between compounds in the embedding space and ranking their likelihood of becoming effective drug candidates. We further establish theoretical guarantees for the stability properties of our proposed MP signatures, and demonstrate that our models, enhanced by the MP signatures, outperform state-of-the-art methods on benchmark datasets by a wide and highly statistically significant margin (e.g., 93% gain for Cleves-Jain and 54% gain for DUD-E Diverse dataset).
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功能配准算法表示点云为函数(例如,空间占用场),避免了常规最小二乘Quares注册算法中不可靠的对应估计。但是,现有的功能注册算法在计算上很昂贵。此外,在基于CAD模型的对象本地化等任务中,必须使用未知量表的注册能力,但是功能注册中没有这种支持。在这项工作中,我们提出了一种比例不变的线性时间复杂性功能配准算法。我们通过使用正顺序基函数在功能之间的L2距离之间有效地近似实现线性时间复杂性。正统基函数的使用导致与最小二乘配准兼容的公式。受益于最小二乘的公式,我们使用翻译反转不变测量的理论来解除尺度估计,从而实现规模不变的注册。我们在标准的3D注册基准上评估了所提出的算法,称为FLS(功能最小二乘),显示FLS的数量级比最先进的功能配准算法快,而无需损害准确性和鲁棒性。 FLS还胜过基于最小二乘的最小二乘注册算法,其精度和鲁棒性具有已知和未知量表。最后,我们证明将FLS应用于具有不同密度和部分重叠的寄存点云,同一类别中不同对象的点云以及带有嘈杂RGB-D测量值的真实世界对象的点云。
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现在,基于视觉的本地化方法为来自机器人技术到辅助技术的无数用例提供了新出现的导航管道。与基于传感器的解决方案相比,基于视觉的定位不需要预安装的传感器基础架构,这是昂贵,耗时和/或通常不可行的。本文中,我们为特定用例提出了一个基于视觉的本地化管道:针对失明和低视力的最终用户的导航支持。给定最终用户在移动应用程序上拍摄的查询图像,该管道利用视觉位置识别(VPR)算法在目标空间的参考图像数据库中找到相似的图像。这些相似图像的地理位置用于采用加权平均方法来估计最终用户的位置和透视N点(PNP)算法的下游任务中,以估计最终用户的方向。此外,该系统实现了Dijkstra的算法,以根据包括Trip Origin和目的地的可通航地图计算最短路径。用于本地化和导航的层压映射是使用定制的图形用户界面构建的,该图形用户界面投影了3D重建的稀疏映射,从一系列图像构建到相应的先验2D楼平面图。用于地图构造的顺序图像可以在预映射步骤中收集,也可以通过公共数据库/公民科学清除。端到端系统可以使用带有自定义移动应用程序的相机安装在任何可互联网的设备上。出于评估目的,在复杂的医院环境中测试了映射和定位。评估结果表明,我们的系统可以以少于1米的平均误差来实现本地化,而无需了解摄像机的固有参数,例如焦距。
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