目前,Covid-19的发展使研究人员可以收集2年内积累的数据集并将其用于预测分析。反过来,这可以评估更复杂的预测模型的效率潜力,包括具有不同预测范围的神经网络。在本文中,我们介绍了基于两个国家的区域数据:美国和俄罗斯的区域数据,对不同类型的方法进行了一致的比较研究结果。我们使用了众所周知的统计方法(例如,指数平滑),一种“明天”方法,以及一套经过来自各个地区数据的经典机器学习模型。与他们一起,考虑了基于长期记忆(LSTM)层的神经网络模型,这些培训样本的培训样本汇总了来自两个国家 /地区的所有地区:美国和俄罗斯。根据MAPE度量,使用交叉验证进行效率评估。结果表明,对于以确认的每日案例数量大幅增加的复杂时期,最佳结果是由在两国所有地区训练的LSTM模型显示的,显示平均平均绝对百分比误差(MAPE)为18%在俄罗斯为30%,37%,31%,41%,50%的预测范围为14、28和42天。
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我们根据CC的4.0许可证lib -sibgmu(大学图书馆流通数据集)为广泛的研究社区开放,并在此数据集中为推荐系统提供基准的主要算法。对于由矢量化器组成的推荐体系结构,将借入的书籍的历史转变为矢量,而基于邻里的推荐人则分别培训,我们表明,将FastText模型用作矢量器将提供竞争成果。
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近年来,生成设计技术已在许多应用领域,尤其是在工程领域中牢固地建立。这些方法证明了由于前景有希望的增长。但是,现有方法受到考虑的问题的特异性受到限制。此外,它们不提供所需的灵活性。在本文中,我们为任意生成设计问题制定了一般方法,并提出了名为Gefest(编码结构的生成进化)的新颖框架。开发的方法基于三个一般原则:采样,估计和优化。这样可以确保方法调整特定生成设计问题的方法的自由度,因此可以构建最合适的方法。进行了一系列实验研究,以确认Gefest框架的有效性。它涉及合成和现实情况(沿海工程,微流体,热力学和油田计划)。 Gefest的柔性结构使得获得超过基线溶液的结果。
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主动同时定位和映射(SLAM)是规划和控制机器人运动以构建周围环境中最准确,最完整的模型的问题。自从三十多年前出现了积极感知的第一项基础工作以来,该领域在不同科学社区中受到了越来越多的关注。这带来了许多不同的方法和表述,并回顾了当前趋势,对于新的和经验丰富的研究人员来说都是非常有价值的。在这项工作中,我们在主动大满贯中调查了最先进的工作,并深入研究了仍然需要注意的公开挑战以满足现代应用程序的需求。为了实现现实世界的部署。在提供了历史观点之后,我们提出了一个统一的问题制定并审查经典解决方案方案,该方案将问题分解为三个阶段,以识别,选择和执行潜在的导航措施。然后,我们分析替代方法,包括基于深入强化学习的信念空间规划和现代技术,以及审查有关多机器人协调的相关工作。该手稿以讨论新的研究方向的讨论,解决可再现的研究,主动的空间感知和实际应用,以及其他主题。
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将3D坐标映射到签名距离函数(SDF)或占用值的神经网络具有启用对象形状的高保真隐式表示。本文开发了一种新的形状模型,允许通过优化连续符号定向距离功能(SDDF)来合成新颖距离视图。与Deep SDF模型类似,我们的SDDF配方可以代表整个类别的形状并从部分输入数据中跨越形状填写或插入。与SDF不同,该SDF在任何方向上测量到最近表面的距离,SDDF测量给定方向的距离。这允许训练没有3D形状监控的SDDF模型,仅使用距离测量,从深度相机或激光雷达传感器易获得。我们的模型还通过直接在任意位置和观察方向上直接预测距离,去除像表面提取或渲染的后处理步骤。与深色视角综合技术不同,例如培训高容量黑盒型号的神经辐射字段,我们的模型通过构造SDDF值沿着观察方向线性降低的性质。这种结构约束不仅导致维度降低,而且还提供了关于SDDF预测的准确性的分析信心,无论到物体表面的距离如何。
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Variational inference uses optimization, rather than integration, to approximate the marginal likelihood, and thereby the posterior, in a Bayesian model. Thanks to advances in computational scalability made in the last decade, variational inference is now the preferred choice for many high-dimensional models and large datasets. This tutorial introduces variational inference from the parametric perspective that dominates these recent developments, in contrast to the mean-field perspective commonly found in other introductory texts.
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Knowledge graphs (KG) have served as the key component of various natural language processing applications. Commonsense knowledge graphs (CKG) are a special type of KG, where entities and relations are composed of free-form text. However, previous works in KG completion and CKG completion suffer from long-tail relations and newly-added relations which do not have many know triples for training. In light of this, few-shot KG completion (FKGC), which requires the strengths of graph representation learning and few-shot learning, has been proposed to challenge the problem of limited annotated data. In this paper, we comprehensively survey previous attempts on such tasks in the form of a series of methods and applications. Specifically, we first introduce FKGC challenges, commonly used KGs, and CKGs. Then we systematically categorize and summarize existing works in terms of the type of KGs and the methods. Finally, we present applications of FKGC models on prediction tasks in different areas and share our thoughts on future research directions of FKGC.
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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.
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Unsupervised domain adaptation (UDA) for semantic segmentation is a promising task freeing people from heavy annotation work. However, domain discrepancies in low-level image statistics and high-level contexts compromise the segmentation performance over the target domain. A key idea to tackle this problem is to perform both image-level and feature-level adaptation jointly. Unfortunately, there is a lack of such unified approaches for UDA tasks in the existing literature. This paper proposes a novel UDA pipeline for semantic segmentation that unifies image-level and feature-level adaptation. Concretely, for image-level domain shifts, we propose a global photometric alignment module and a global texture alignment module that align images in the source and target domains in terms of image-level properties. For feature-level domain shifts, we perform global manifold alignment by projecting pixel features from both domains onto the feature manifold of the source domain; and we further regularize category centers in the source domain through a category-oriented triplet loss and perform target domain consistency regularization over augmented target domain images. Experimental results demonstrate that our pipeline significantly outperforms previous methods. In the commonly tested GTA5$\rightarrow$Cityscapes task, our proposed method using Deeplab V3+ as the backbone surpasses previous SOTA by 8%, achieving 58.2% in mIoU.
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The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.
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