我们研究了通过机器学习从欧几里得相关函数重建光谱函数的逆问题。我们提出了一个新型的神经网络SVAE,该网络基于变异自动编码器(VAE),可以自然应用于逆问题。 SVAE的突出特征是,作为损失函数中的先验信息包含了频谱函数的地面真实值的香农 - jaynes熵项,要最小化。我们使用高斯混合模型产生的一般光谱函数训练网络。作为一项测试,我们使用由一个由一个共振峰制成的四种不同类型的物理动机函数产生的相关器,连续项和使用非相关性QCD获得的扰动光谱函数。从模拟数据测试我们发现,在大多数情况下,SVAE与重建光谱函数质量的最大熵方法(MEM)相媲美,甚至在光谱函数具有尖峰的情况下且数据数量不足的情况下,SVAE与MEM的表现相当。相关器中的点。通过在淬火晶格QCD中获得的charmonium的时间相关函数应用于$ 128^3 \ times96 $ lattices和$ 128^3 \ times48 $ lattices,我们找到了$ 128^3 \ times96 $ lattices in 0.75 $ t_c $ on 0.75 $ t_c $ on 0.75 $ t_c $,我们发现,我们找到了,我们找到了,我们找到从SVAE和MEM提取的$ \ eta_c $的共振峰值对晶格模拟中采用的时间方向($ n_ \ tau $)的点数具有很大的依赖为了解决$ \ eta_c $的命运为1.5 $ t_c $。
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Importance: Social determinants of health (SDOH) are known to be associated with increased risk of suicidal behaviors, but few studies utilized SDOH from unstructured electronic health record (EHR) notes. Objective: To investigate associations between suicide and recent SDOH, identified using structured and unstructured data. Design: Nested case-control study. Setting: EHR data from the US Veterans Health Administration (VHA). Participants: 6,122,785 Veterans who received care in the US VHA between October 1, 2010, and September 30, 2015. Exposures: Occurrence of SDOH over a maximum span of two years compared with no occurrence of SDOH. Main Outcomes and Measures: Cases of suicide deaths were matched with 4 controls on birth year, cohort entry date, sex, and duration of follow-up. We developed an NLP system to extract SDOH from unstructured notes. Structured data, NLP on unstructured data, and combining them yielded seven, eight and nine SDOH respectively. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. Results: In our cohort, 8,821 Veterans committed suicide during 23,725,382 person-years of follow-up (incidence rate 37.18 /100,000 person-years). Our cohort was mostly male (92.23%) and white (76.99%). Across the six common SDOH as covariates, NLP-extracted SDOH, on average, covered 84.38% of all SDOH occurrences. All SDOH, measured by structured data and NLP, were significantly associated with increased risk of suicide. The SDOH with the largest effects was legal problems (aOR=2.67, 95% CI=2.46-2.89), followed by violence (aOR=2.26, 95% CI=2.11-2.43). NLP-extracted and structured SDOH were also associated with suicide. Conclusions and Relevance: NLP-extracted SDOH were always significantly associated with increased risk of suicide among Veterans, suggesting the potential of NLP in public health studies.
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A central problem in computational biophysics is protein structure prediction, i.e., finding the optimal folding of a given amino acid sequence. This problem has been studied in a classical abstract model, the HP model, where the protein is modeled as a sequence of H (hydrophobic) and P (polar) amino acids on a lattice. The objective is to find conformations maximizing H-H contacts. It is known that even in this reduced setting, the problem is intractable (NP-hard). In this work, we apply deep reinforcement learning (DRL) to the two-dimensional HP model. We can obtain the conformations of best known energies for benchmark HP sequences with lengths from 20 to 50. Our DRL is based on a deep Q-network (DQN). We find that a DQN based on long short-term memory (LSTM) architecture greatly enhances the RL learning ability and significantly improves the search process. DRL can sample the state space efficiently, without the need of manual heuristics. Experimentally we show that it can find multiple distinct best-known solutions per trial. This study demonstrates the effectiveness of deep reinforcement learning in the HP model for protein folding.
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Automatic keyword extraction (AKE) has gained more importance with the increasing amount of digital textual data that modern computing systems process. It has various applications in information retrieval (IR) and natural language processing (NLP), including text summarisation, topic analysis and document indexing. This paper proposes a simple but effective post-processing-based universal approach to improve the performance of any AKE methods, via an enhanced level of semantic-awareness supported by PoS-tagging. To demonstrate the performance of the proposed approach, we considered word types retrieved from a PoS-tagging step and two representative sources of semantic information -- specialised terms defined in one or more context-dependent thesauri, and named entities in Wikipedia. The above three steps can be simply added to the end of any AKE methods as part of a post-processor, which simply re-evaluate all candidate keywords following some context-specific and semantic-aware criteria. For five state-of-the-art (SOTA) AKE methods, our experimental results with 17 selected datasets showed that the proposed approach improved their performances both consistently (up to 100\% in terms of improved cases) and significantly (between 10.2\% and 53.8\%, with an average of 25.8\%, in terms of F1-score and across all five methods), especially when all the three enhancement steps are used. Our results have profound implications considering the ease to apply our proposed approach to any AKE methods and to further extend it.
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在本研究说明中,我在收购驱动的框架内得出了针对语言的显式动力系统(Niyogi \&Berwick,1997; Niyogi,2006年),假设儿童/学习者遵守公差原则(Yang,2016年),以确定规则是否是规则在语言获取过程中的生产力。我考虑了不同的理论参数,例如人口大小(有限与无限)以及为学习者提供数据的前几代人数。准备此处获得的动力学的多个模拟,并准备了变音语言数据的应用程序,因此未包括在第一个音符中。
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基于决策树(DT)的分类和回归思想,最近提议在总体分类和回归任务中提供更高的性能。以更高的计算复杂性为代价,达到了其性能的改进。在这项工作中,我们研究了两种加速SLM的方法。首先,我们采用粒子群优化(PSO)算法来加快对当前尺寸的线性组合表示的判别尺寸的搜索。线性组合中最佳权重的搜索在计算上很重。它是通过原始SLM中的概率搜索来完成的。 PSO的SLM加速需要减少10-20倍的迭代。其次,我们利用SLM实施中的并行处理。实验结果表明,加速的SLM方法在训练时间中达到577的速度系数,同时保持原始SLM的可比分类/回归性能。
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面对抗泡沫(FAS)和伪造探测在保护面部生物识别系统免受演示攻击(PAS)和恶性数字操作(例如,Deepfakes)中的生物识别系统中起着至关重要的作用。尽管大规模数据和强大的深层模型有希望的表现,但现有方法的概括问题仍然是一个空旷的问题。最近的大多数方法都集中在1)单峰视觉外观或生理学(即远程光摄影学(RPPG))线索;和2)用于FAS或面部伪造检测的分离特征表示。一方面,单峰外观和RPPG功能分别容易受到高保真的面孔3D面膜和视频重播攻击的影响,从而激发了我们设计可靠的多模式融合机制,用于广义面部攻击检​​测。另一方面,FAS和面部伪造探测任务(例如,定期的RPPG节奏和BONAFIDE的香草外观)都有丰富的共同特征,提供了可靠的证据来设计联合FAS和面部伪造探测系统,以多任务学习方式。在本文中,我们使用视觉外观和生理RPPG提示建立了第一个关节面欺骗和伪造的检测基准。为了增强RPPG的周期性歧视,我们使用两种面部时空时代的RPPG信号图及其连续小波转换为输入的两分支生理网络。为了减轻模态偏差并提高融合功效,我们在多模式融合之前对外观和RPPG特征进行了加权批次和层归一化。我们发现,可以通过对这两个任务的联合培训来改善单峰(外观或RPPG)和多模式(外观+RPPG)模型的概括能力。我们希望这种新的基准将促进FAS和DeepFake检测社区的未来研究。
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以人为本的人工智能考虑了人工智能表现的经验。尽管丰富的研究一直在通过全自动或弱监督学习来帮助AI实现超人类的表现,但较少的努力正在尝试AI如何量身定制人类对人类首选技能水平的限制。在这项工作中,我们指导课程加强学习结果朝着首选的绩效水平,通过从人类的决策过程中学习而不是太困难也不容易。为了实现这一目标,我们开发了一个便携式交互式平台,使用户能够通过操纵任务难度,观察性能并提供课程反馈来在线与代理商进行交互。我们的系统高度可行,使人类可以训练大规模的增强学习应用程序,这些学习应用需要数百万没有服务器的样品。结果证明了互动课程对涉及人类在环的增强学习的有效性。它显示强化学习绩效可以成功地与人类所需的难度水平同步调整。我们认为,这项研究将为实现流动和个性化的适应性困难打开新的大门。
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提出了一种统计注意力定位(SAL)方法,以促进本工作中的对象分类任务。 SAL由三个步骤组成:1)通过决策统计数据的初步注意窗口选择,2)注意力图改进和3)矩形注意区域的最终确定。 SAL计算本地平方窗口的软性决定分数,并使用它们来识别步骤1中的明显区域。为了适应各种尺寸和形状的对象,SAL优化了初步结果,并在步骤2中获得了更灵活形状的注意力图。最后, SAL使用步骤3中的精制注意图和边界框正则化产生矩形注意区域。作为应用程序,我们采用E-PixelHop,这是基于连续的子空间学习(SSL)的对象分类解决方案,作为基线。我们应用SAL以获取裁剪和调整大小的注意区域作为替代输入。整个图像的分类结果以及注意区域都被结合起来,以达到最高的分类精度。给出了CIFAR-10数据集上的实验,以证明SAL辅助对象分类方法的优势。
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存储数十万个材料结构及其相应特性的开放材料数据库已成为现代计算材料科学的基石。然而,模拟的原始输出,例如分子动力学模拟的轨迹和密度功能理论计算的电荷密度,通常由于其较大的尺寸而没有共享。在这项工作中,我们描述了一个基于云的平台,以促进原始数据的共享,并在云中启用快速的后处理以提取用户定义的新属性。作为初始演示,我们的数据库目前包括6286个用于无定形聚合物电解质的分子动力学轨迹和5.7吨数据库。我们在https://github.com/tri-amdd/htp_md上创建一个公共分析库,使用专家设计的功能和机器学习模型,从原始数据中提取多个属性。该分析是通过云中的计算自动运行的,然后结果填充可以公开访问的数据库。我们的平台鼓励用户通过公共接口贡献新的轨迹数据和分析功能。新分析的属性将纳入数据库。最后,我们在https://www.htpmd.matr.io上创建了一个前端用户界面,以浏览和可视化数据。我们设想该平台将是一种为计算材料科学界共享原始数据和新见解的新方法。
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