相机陷阱是监视收集大量图片的野生动植物的策略。从每个物种收集的图像数量通常遵循长尾分布,即,一些类有大量实例,而许多物种只有很小的比例。尽管在大多数情况下,这些稀有物种是生态学家感兴趣的类别,但在使用深度学习模型时,它们通常被忽略,因为这些模型需要大量的培训图像。在这项工作中,我们系统地评估了最近提出的技术 - 即平方根重新采样,平衡的焦点损失和平衡的组软效果 - 以解决相机陷阱图像中动物物种的长尾视觉识别。为了得出更一般的结论,我们评估了四个计算机视觉模型家族(Resnet,Mobilenetv3,EdgitionNetV2和Swin Transformer)和具有不同特征不同的相机陷阱数据集的四个家族。最初,我们用最新的培训技巧准备了一个健壮的基线,然后应用了改善长尾识别的方法。我们的实验表明,Swin Transformer可以在不应用任何其他方法处理不平衡的方法的情况下达到稀有类别的高性能,WCS数据集的总体准确性为88.76%,Snapshot Serengeti的总体准确性为94.97%,考虑到基于位置的火车/测试拆分。通常,平方根采样是一种方法,它最大程度地提高了少数族裔阶级的表现约为10%,但以降低多数类准确性至少4%的代价。这些结果促使我们使用合并平方根采样和基线的合奏提出了一种简单有效的方法。拟议的方法实现了尾巴级的性能与头等阶级准确性的成本之间的最佳权衡。
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太阳能动力学天文台(SDO)是NASA多光谱十年的长达任务,每天都在日常产生来自Sun的观测数据的trabytes,以证明机器学习方法的潜力并铺路未来深空任务计划的方式。特别是,在最近的几项研究中提出了使用图像到图像翻译实际上产生极端超紫罗兰通道的想法,这是一种增强任务较少通道的提高任务的方法,并且由于低下链接而减轻了挑战。深空的速率。本文通过关注四个通道和基于编码器的建筑的排列来研究这种深度学习方法的潜力和局限性,并特别注意太阳表面的形态特征和亮度如何影响神经网络预测。在这项工作中,我们想回答以下问题:可以将通过图像到图像翻译产生的太阳电晕的合成图像用于太阳的科学研究吗?分析强调,神经网络在计数率(像素强度)上产生高质量的图像,通常可以在1%误差范围内跨通道跨通道重现协方差。但是,模型性能在极高的能量事件(如耀斑)的对应关系中大大减少,我们认为原因与此类事件的稀有性有关,这对模型训练构成了挑战。
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由能够连接和交换消息的越来越多的移动设备而激励,我们提出了一种旨在模拟和分析网络中节点移动性的方法。我们注意到文献中的许多现有解决方案依赖于直接在节点联系人图表上计算的拓扑测量,旨在捕获节点在有利于原型设计,设计和部署移动网络的连接和移动模式方面的重要性。但是,每个措施都具有其特异性,并且无法概括最终随时间变化的节点重要性概念。与以前的方法不同,我们的方法基于节点嵌入方法,该方法模型和推出在保留其空间和时间特征的同时在移动性和连接模式中对节点的重要性。我们专注于基于一丝小组会议的案例研究。结果表明,我们的方法提供了提取不同移动性和连接模式的丰富表示,这可能有助于移动网络中的各种应用和服务。
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Traditionally, data analysis and theory have been viewed as separate disciplines, each feeding into fundamentally different types of models. Modern deep learning technology is beginning to unify these two disciplines and will produce a new class of predictively powerful space weather models that combine the physical insights gained by data and theory. We call on NASA to invest in the research and infrastructure necessary for the heliophysics' community to take advantage of these advances.
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Machine Learning algorithms have been extensively researched throughout the last decade, leading to unprecedented advances in a broad range of applications, such as image classification and reconstruction, object recognition, and text categorization. Nonetheless, most Machine Learning algorithms are trained via derivative-based optimizers, such as the Stochastic Gradient Descent, leading to possible local optimum entrapments and inhibiting them from achieving proper performances. A bio-inspired alternative to traditional optimization techniques, denoted as meta-heuristic, has received significant attention due to its simplicity and ability to avoid local optimums imprisonment. In this work, we propose to use meta-heuristic techniques to fine-tune pre-trained weights, exploring additional regions of the search space, and improving their effectiveness. The experimental evaluation comprises two classification tasks (image and text) and is assessed under four literature datasets. Experimental results show nature-inspired algorithms' capacity in exploring the neighborhood of pre-trained weights, achieving superior results than their counterpart pre-trained architectures. Additionally, a thorough analysis of distinct architectures, such as Multi-Layer Perceptron and Recurrent Neural Networks, attempts to visualize and provide more precise insights into the most critical weights to be fine-tuned in the learning process.
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Early recognition of clinical deterioration (CD) has vital importance in patients' survival from exacerbation or death. Electronic health records (EHRs) data have been widely employed in Early Warning Scores (EWS) to measure CD risk in hospitalized patients. Recently, EHRs data have been utilized in Machine Learning (ML) models to predict mortality and CD. The ML models have shown superior performance in CD prediction compared to EWS. Since EHRs data are structured and tabular, conventional ML models are generally applied to them, and less effort is put into evaluating the artificial neural network's performance on EHRs data. Thus, in this article, an extremely boosted neural network (XBNet) is used to predict CD, and its performance is compared to eXtreme Gradient Boosting (XGBoost) and random forest (RF) models. For this purpose, 103,105 samples from thirteen Brazilian hospitals are used to generate the models. Moreover, the principal component analysis (PCA) is employed to verify whether it can improve the adopted models' performance. The performance of ML models and Modified Early Warning Score (MEWS), an EWS candidate, are evaluated in CD prediction regarding the accuracy, precision, recall, F1-score, and geometric mean (G-mean) metrics in a 10-fold cross-validation approach. According to the experiments, the XGBoost model obtained the best results in predicting CD among Brazilian hospitals' data.
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Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License.
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传播模型已被证明对各种应用程序有效,例如图像,音频和图形生成。其他重要的应用是图像超分辨率和逆问题的解决方案。最近,一些作品使用了随机微分方程(SDE)将扩散模型推广到连续时间。在这项工作中,我们介绍SDE来生成超分辨率的面部图像。据我们所知,这是SDE首次用于此类应用程序。所提出的方法比基于扩散模型的现有超级分辨率方法提供了改进的峰值信噪比(PSNR),结构相似性指数(SSIM)和一致性。特别是,我们还评估了该方法在面部识别任务中的潜在应用。通用面部特征提取器用于比较超分辨率图像与地面真相,并获得了与其他方法相比,获得了卓越的结果。我们的代码可在https://github.com/marcelowds/sr-sde上公开获取
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当歌曲创作或演奏时,歌手/词曲作者通常会出现通过它表达感受或情感的意图。对于人类而言,将音乐作品或表演中的情感与观众的主观感知相匹配可能会非常具有挑战性。幸运的是,此问题的机器学习方法更简单。通常,它需要一个数据集,从该数据集中提取音频功能以将此信息呈现给数据驱动的模型,从而又将训练以预测给定歌曲与目标情绪匹配的概率是什么。在本文中,我们研究了最近出版物中最常见的功能和模型来解决此问题,揭示了哪些最适合在无伴奏歌曲中识别情感。
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我们研究了图结构识别的问题,即在时间序列之间恢复依赖图的图。我们将这些时间序列数据建模为线性随机网络动力学系统状态的组成部分。我们假设部分可观察性,其中仅观察到一个包含网络的节点子集的状态演变。我们设计了一个从观察到的时间序列计算的新功能向量,并证明这些特征是线性可分离的,即存在一个超平面,该超平面将与连接的节点成对相关的特征群体与与断开对相关的节点相关联。这使得可以训练各种分类器进行因果推理的功能。特别是,我们使用这些功能来训练卷积神经网络(CNN)。由此产生的因果推理机制优于最先进的W.R.T.样品复杂性。受过训练的CNN概括了结构上不同的网络(密集或稀疏)和噪声级别的轮廓。值得注意的是,他们在通过合成网络(随机图的实现)训练时也很好地概括了现实世界网络。最后,提出的方法始终以成对的方式重建图,也就是说,通过确定每对相应的时间序列中的每对节点中是否存在边缘或箭头或不存在箭头。这符合大规模系统的框架,在该系统中,网络中所有节点的观察或处理都令人难以置信。
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