癌症是一种复杂的疾病,具有重大的社会和经济影响。高通量分子测定的进步以及进行高质量多摩斯测量的成本降低,通过机器学习促进了见解。先前的研究表明,使用多个OMIC预测生存和分层癌症患者的希望。在本文中,我们开发了一种有监督的自动编码器(SAE)模型,用于基于生存的多摩变集成,该模型在以前的工作中改进,并报告一种具体的监督自动编码器模型(CSAE),该模型(CSAE)也使用功能选择来共同重建输入功能。作为预测生存。我们的实验表明,我们的模型表现优于或与一些最常用的基线相提并论,同时提供更好的生存分离(SAE)或更容易解释(CSAE)。我们还对我们的模型进行了特征选择稳定性分析,并注意到与通常与生存有关的特征存在幂律关系。该项目的代码可在以下网址获得:https://github.com/phcavelar/coxae
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Recently, there has been an interest in improving the resources available in Intrusion Detection System (IDS) techniques. In this sense, several studies related to cybersecurity show that the environment invasions and information kidnapping are increasingly recurrent and complex. The criticality of the business involving operations in an environment using computing resources does not allow the vulnerability of the information. Cybersecurity has taken on a dimension within the universe of indispensable technology in corporations, and the prevention of risks of invasions into the environment is dealt with daily by Security teams. Thus, the main objective of the study was to investigate the Ensemble Learning technique using the Stacking method, supported by the Support Vector Machine (SVM) and k-Nearest Neighbour (kNN) algorithms aiming at an optimization of the results for DDoS attack detection. For this, the Intrusion Detection System concept was used with the application of the Data Mining and Machine Learning Orange tool to obtain better results
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Despite the impact of psychiatric disorders on clinical health, early-stage diagnosis remains a challenge. Machine learning studies have shown that classifiers tend to be overly narrow in the diagnosis prediction task. The overlap between conditions leads to high heterogeneity among participants that is not adequately captured by classification models. To address this issue, normative approaches have surged as an alternative method. By using a generative model to learn the distribution of healthy brain data patterns, we can identify the presence of pathologies as deviations or outliers from the distribution learned by the model. In particular, deep generative models showed great results as normative models to identify neurological lesions in the brain. However, unlike most neurological lesions, psychiatric disorders present subtle changes widespread in several brain regions, making these alterations challenging to identify. In this work, we evaluate the performance of transformer-based normative models to detect subtle brain changes expressed in adolescents and young adults. We trained our model on 3D MRI scans of neurotypical individuals (N=1,765). Then, we obtained the likelihood of neurotypical controls and psychiatric patients with early-stage schizophrenia from an independent dataset (N=93) from the Human Connectome Project. Using the predicted likelihood of the scans as a proxy for a normative score, we obtained an AUROC of 0.82 when assessing the difference between controls and individuals with early-stage schizophrenia. Our approach surpassed recent normative methods based on brain age and Gaussian Process, showing the promising use of deep generative models to help in individualised analyses.
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深度神经网络在医学图像分析中带来了显着突破。但是,由于其渴望数据的性质,医学成像项目中适度的数据集大小可能会阻碍其全部潜力。生成合成数据提供了一种有希望的替代方案,可以补充培训数据集并进行更大范围的医学图像研究。最近,扩散模型通过产生逼真的合成图像引起了计算机视觉社区的注意。在这项研究中,我们使用潜在扩散模型探索从高分辨率3D脑图像中生成合成图像。我们使用来自英国生物银行数据集的T1W MRI图像(n = 31,740)来训练我们的模型,以了解脑图像的概率分布,该脑图像以协变量为基础,例如年龄,性别和大脑结构量。我们发现我们的模型创建了现实的数据,并且可以使用条件变量有效地控制数据生成。除此之外,我们创建了一个带有100,000次脑图像的合成数据集,并使科学界公开使用。
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使用机器学习算法从未标记的文本中提取知识可能很复杂。文档分类和信息检索是两个应用程序,可以从无监督的学习(例如文本聚类和主题建模)中受益,包括探索性数据分析。但是,无监督的学习范式提出了可重复性问题。初始化可能会导致可变性,具体取决于机器学习算法。此外,关于群集几何形状,扭曲可能会产生误导。在原因中,异常值和异常的存在可能是决定因素。尽管初始化和异常问题与文本群集和主题建模相关,但作者并未找到对它们的深入分析。这项调查提供了这些亚地区的系统文献综述(2011-2022),并提出了共同的术语,因为类似的程序具有不同的术语。作者描述了研究机会,趋势和开放问题。附录总结了与审查的作品直接或间接相关的文本矢量化,分解和聚类算法的理论背景。
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强化学习(RL)通过原始像素成像和连续的控制任务在视频游戏中表现出了令人印象深刻的表现。但是,RL的性能较差,例如原始像素图像,例如原始像素图像。人们普遍认为,基于物理状态的RL策略(例如激光传感器测量值)比像素学习相比会产生更有效的样品结果。这项工作提出了一种新方法,该方法从深度地图估算中提取信息,以教授RL代理以执行无人机导航(UAV)的无地图导航。我们提出了深度模仿的对比度无监督的优先表示(DEPTH-CUPRL),该表示具有优先重播记忆的估算图像的深度。我们使用RL和对比度学习的组合,根据图像的RL问题引发。从无人驾驶汽车(UAV)对结果的分析中,可以得出结论,我们的深度cuprl方法在无MAP导航能力中对决策和优于最先进的像素的方法有效。
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深层生成模型已成为检测数据中任意异常的有前途的工具,并分配了手动标记的必要性。最近,自回旋变压器在医学成像中取得了最先进的性能。但是,这些模型仍然具有一些内在的弱点,例如需要将图像建模为1D序列,在采样过程中误差的积累以及与变压器相关的显着推理时间。去核扩散概率模型是一类非自动回旋生成模型,最近显示出可以在计算机视觉中产生出色的样品(超过生成的对抗网络),并实现与变压器具有竞争力同时具有快速推理时间的对数可能性。扩散模型可以应用于自动编码器学到的潜在表示,使其易于扩展,并适用于高维数据(例如医学图像)的出色候选者。在这里,我们提出了一种基于扩散模型的方法,以检测和分段脑成像中的异常。通过在健康数据上训练模型,然后探索其在马尔可夫链上的扩散和反向步骤,我们可以识别潜在空间中的异常区域,因此可以确定像素空间中的异常情况。我们的扩散模型与一系列具有2D CT和MRI数据的实验相比,具有竞争性能,涉及合成和实际病理病变,推理时间大大减少,从而使它们的用法在临床上可行。
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压力溃疡在ICU患者中具有很高的患病率,但如果以初始阶段识别,则可预防。在实践中,布拉登规模用于分类高风险患者。本文通过使用MIMIC-III V1.4中可用的数据调查了在电子健康中使用机器学习记录数据的使用。制定了两个主要贡献:评估考虑在住宿期间所有预测的模型的新方法,以及用于机器学习模型的新培训方法。结果与现有技术相比,表现出卓越的性能;此外,所有型号在精密召回曲线中的每个工作点都超过了Braden刻度。 - - les \〜oes por按\〜ao possuem alta preval \ ^ encia em pacientes de Uti e s \〜ao preven \'iveis ao serem endicidificadas em Est \'agios Iniciais。 na pr \'atica materiza-se a escala de braden para classifica \ c {c} \〜ao de pacientes em risco。 Este Artigo Investiga o Uso de Apenizado de M \'Aquina Em Dados de Registros Eletr \ ^ Onicos Para Este Fim,Parir Da Base dados Mimic-III V1.4。 s \〜ao feitas duas contribui \ c {c} \〜oes principais:uma nova abordagem para a avalia \ c {c} \〜ao dos modelos e da escala da escala de braden levando em conta todas作为predi \ c {c} \ 〜oes feitas ao longo das interna \ c {c} \〜oes,euro novo m \'etodo de treinamento para os modelos de aprendizo de m \'aquina。 os结果os overidos superam o estado da arte everifica-se que os modelos superam意义a escala de braden em todos oS pontos de Opera \ c {c} \〜〜ao da curva de precis \〜ao por sensibilidade。
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In this work, we demonstrate the offline FPGA realization of both recurrent and feedforward neural network (NN)-based equalizers for nonlinearity compensation in coherent optical transmission systems. First, we present a realization pipeline showing the conversion of the models from Python libraries to the FPGA chip synthesis and implementation. Then, we review the main alternatives for the hardware implementation of nonlinear activation functions. The main results are divided into three parts: a performance comparison, an analysis of how activation functions are implemented, and a report on the complexity of the hardware. The performance in Q-factor is presented for the cases of bidirectional long-short-term memory coupled with convolutional NN (biLSTM + CNN) equalizer, CNN equalizer, and standard 1-StpS digital back-propagation (DBP) for the simulation and experiment propagation of a single channel dual-polarization (SC-DP) 16QAM at 34 GBd along 17x70km of LEAF. The biLSTM+CNN equalizer provides a similar result to DBP and a 1.7 dB Q-factor gain compared with the chromatic dispersion compensation baseline in the experimental dataset. After that, we assess the Q-factor and the impact of hardware utilization when approximating the activation functions of NN using Taylor series, piecewise linear, and look-up table (LUT) approximations. We also show how to mitigate the approximation errors with extra training and provide some insights into possible gradient problems in the LUT approximation. Finally, to evaluate the complexity of hardware implementation to achieve 400G throughput, fixed-point NN-based equalizers with approximated activation functions are developed and implemented in an FPGA.
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To circumvent the non-parallelizability of recurrent neural network-based equalizers, we propose knowledge distillation to recast the RNN into a parallelizable feedforward structure. The latter shows 38\% latency decrease, while impacting the Q-factor by only 0.5dB.
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