新的纳米级技术的出现对辐射环境中的可靠电子系统造成了重大挑战。少数种类的辐射等全电离剂量（TID）效应通常导致在这种纳米级电子设备上的永久性损坏，以及当前最先进的技术，以使用昂贵的辐射硬化装置。本文重点介绍了一种新颖且不同的方法：在消费者电子级现场可编程门阵列（FPGA）上使用机器学习算法来解决TID效果并在停止工作之前监控它们替换。这种情况有一个研究挑战，以期待电路板因TID效应而导致总失效。我们观察到γ辐射下FPGA板的内部测量，并使用了三种不同的异常检测机学习（ML）算法来检测伽马辐射环境中的传感器测量中的异常。统计结果表明伽马辐射曝光水平与板测量之间的高度显着关系。此外，我们的异常检测结果表明，具有径向基函数内核的单级支持向量机的平均召回得分为0.95。此外，在电路板停止工作之前，可以检测到所有异常。

The Internet of Things (IoT) is a system that connects physical computing devices, sensors, software, and other technologies. Data can be collected, transferred, and exchanged with other devices over the network without requiring human interactions. One challenge the development of IoT faces is the existence of anomaly data in the network. Therefore, research on anomaly detection in the IoT environment has become popular and necessary in recent years. This survey provides an overview to understand the current progress of the different anomaly detection algorithms and how they can be applied in the context of the Internet of Things. In this survey, we categorize the widely used anomaly detection machine learning and deep learning techniques in IoT into three types: clustering-based, classification-based, and deep learning based. For each category, we introduce some state-of-the-art anomaly detection methods and evaluate the advantages and limitations of each technique.

装有传感器，执行器和电子控制单元（ECU）的现代车辆可以分为几个称为功能工作组（FWGS）的操作子系统。这些FWG的示例包括发动机系统，变速箱，燃油系统，制动器等。每个FWG都有相关的传感器通道，可以衡量车辆操作条件。这种丰富的数据环境有利于预测维护（PDM）技术的开发。削弱各种PDM技术的是需要强大的异常检测模型，该模型可以识别出明显偏离大多数数据的事件或观察结果，并且不符合正常车辆操作行为的明确定义的概念。在本文中，我们介绍了车辆性能，可靠性和操作（VEPRO）数据集，并使用它来创建一种基于多阶段的异常检测方法。利用时间卷积网络（TCN），我们的异常检测系统可以达到96％的检测准确性，并准确预测91％的真实异常。当利用来自多个FWG的传感器通道时，我们的异常检测系统的性能会改善。

A Digital Twin (DT) is a simulation of a physical system that provides information to make decisions that add economic, social or commercial value. The behaviour of a physical system changes over time, a DT must therefore be continually updated with data from the physical systems to reflect its changing behaviour. For resource-constrained systems, updating a DT is non-trivial because of challenges such as on-board learning and the off-board data transfer. This paper presents a framework for updating data-driven DTs of resource-constrained systems geared towards system health monitoring. The proposed solution consists of: (1) an on-board system running a light-weight DT allowing the prioritisation and parsimonious transfer of data generated by the physical system; and (2) off-board robust updating of the DT and detection of anomalous behaviours. Two case studies are considered using a production gas turbine engine system to demonstrate the digital representation accuracy for real-world, time-varying physical systems.

Time series anomaly detection has applications in a wide range of research fields and applications, including manufacturing and healthcare. The presence of anomalies can indicate novel or unexpected events, such as production faults, system defects, or heart fluttering, and is therefore of particular interest. The large size and complex patterns of time series have led researchers to develop specialised deep learning models for detecting anomalous patterns. This survey focuses on providing structured and comprehensive state-of-the-art time series anomaly detection models through the use of deep learning. It providing a taxonomy based on the factors that divide anomaly detection models into different categories. Aside from describing the basic anomaly detection technique for each category, the advantages and limitations are also discussed. Furthermore, this study includes examples of deep anomaly detection in time series across various application domains in recent years. It finally summarises open issues in research and challenges faced while adopting deep anomaly detection models.

分层时间记忆（HTM）是一种无监督的学习算法，其灵感来自Neocortex的功能，可用于连续处理流数据并检测异常，而无需大量数据进行培训，也不需要标记数据。 HTM还能够从样本中不断学习，提供一个始终是关于观察的模型。这些特性使HTM特别适用于支持云系统中的在线故障预测，这是具有动态变化行为的系统必须监视以预测问题。本文介绍了在故障预测的背景下评估HTM的第一个系统研究。考虑到72个HTM配置所获得的HTM配置到Clearwater云系统中引入的12种不同类型的故障表明，HTM可以帮助预测具有足够有效性（F-Measure = 0.76）的失败，代表有趣的实际替代方案（半 - ）监督算法。

及时，准确地检测功率电子中的异常，对于维持复杂的生产系统而变得越来越重要。强大而可解释的策略有助于减少系统的停机时间，并抢占或减轻基础设施网络攻击。这项工作从解释当前数据集和机器学习算法输出中存在的不确定性类型开始。然后引入和分析三种打击这些不确定性的技术。我们进一步介绍了两种异常检测和分类方法，即矩阵曲线算法和异常变压器，它们是在电源电子转换器数据集的背景下应用的。具体而言，矩阵配置文件算法被证明非常适合作为检测流时间序列数据中实时异常的概括方法。迭代矩阵配置文件的结构python库实现用于创建检测器。创建了一系列自定义过滤器并将其添加到检测器中，以调整其灵敏度，回忆和检测精度。我们的数值结果表明，通过简单的参数调整，检测器在各种故障场景中提供了高精度和性能。

现代高性能计算（HPC）系统的复杂性日益增加，需要引入自动化和数据驱动的方法，以支持系统管理员为增加系统可用性的努力。异常检测是改善可用性不可或缺的一部分，因为它减轻了系统管理员的负担，并减少了异常和解决方案之间的时间。但是，对当前的最新检测方法进行了监督和半监督，因此它们需要具有异常的人体标签数据集 - 在生产HPC系统中收集通常是不切实际的。基于聚类的无监督异常检测方法，旨在减轻准确的异常数据的需求，到目前为止的性能差。在这项工作中，我们通过提出RUAD来克服这些局限性，RUAD是一种新型的无监督异常检测模型。 Ruad比当前的半监督和无监督的SOA方法取得了更好的结果。这是通过考虑数据中的时间依赖性以及在模型体系结构中包括长短期限内存单元的实现。提出的方法是根据tier-0系统（带有980个节点的Cineca的Marconi100的完整历史）评估的。 RUAD在半监督训练中达到曲线（AUC）下的区域（AUC）为0.763，在无监督的训练中达到了0.767的AUC，这改进了SOA方法，在半监督训练中达到0.747的AUC，无需训练的AUC和0.734的AUC在无处不在的AUC中提高了AUC。训练。它还大大优于基于聚类的当前SOA无监督的异常检测方法，其AUC为0.548。

电力系统状态估计面临着不同类型的异常。这些可能包括由总测量错误或通信系统故障引起的不良数据。根据实施的状态估计方法，负载或发电的突然变化可以视为异常。此外，将电网视为网络物理系统，状态估计变得容易受到虚假数据注射攻击的影响。现有的异常分类方法无法准确对上述三种异常进行分类（区分），尤其是在歧视突然的负载变化和虚假数据注入攻击时。本文提出了一种用于检测异常存在，对异常类型进行分类并识别异常起源的新算法更改或通过错误数据注入攻击针对的状态变量。该算法结合了分析和机器学习（ML）方法。第一阶段通过组合$ \ chi^2 $检测指数来利用一种分析方法来检测异常存在。第二阶段利用ML进行异常类型的分类和其来源的识别，特别是指突然负载变化和错误数据注射攻击的歧视。提出的基于ML的方法经过训练，可以独立于网络配置，该网络配置消除了网络拓扑变化后算法的重新训练。通过在IEEE 14总线测试系统上实施拟议的算法获得的结果证明了拟议算法的准确性和有效性。

日志是确保许多软件系统的可靠性和连续性，尤其是大规模分布式系统的命令。他们忠实地录制运行时信息，以便于系统故障排除和行为理解。由于现代软件系统的大规模和复杂性，日志量已达到前所未有的水平。因此，对于基于逻究的异常检测，常规的手动检查方法甚至传统的基于机器学习的方法变得不切实际，这是一种不切实际的是，作为基于深度学习的解决方案的快速发展的催化剂。然而，目前在诉诸神经网络的代表性日志的异常探测器之间缺乏严格的比较。此外，重新实现过程需要不琐碎的努力，并且可以轻易引入偏差。为了更好地了解不同异常探测器的特性，在本文中，我们提供了六种最先进的方法使用的五种流行神经网络的全面审查和评估。特别是，4种所选方法是无监督的，并且剩下的两个是监督的。这些方法是用两个公开的日志数据集进行评估，其中包含近1600万日志消息和总共有04万个异常实例。我们相信我们的工作可以作为这一领域的基础，为未来的学术研究和工业应用做出贡献。

Semiconductor lasers have been rapidly evolving to meet the demands of next-generation optical networks. This imposes much more stringent requirements on the laser reliability, which are dominated by degradation mechanisms (e.g., sudden degradation) limiting the semiconductor laser lifetime. Physics-based approaches are often used to characterize the degradation behavior analytically, yet explicit domain knowledge and accurate mathematical models are required. Building such models can be very challenging due to a lack of a full understanding of the complex physical processes inducing the degradation under various operating conditions. To overcome the aforementioned limitations, we propose a new data-driven approach, extracting useful insights from the operational monitored data to predict the degradation trend without requiring any specific knowledge or using any physical model. The proposed approach is based on an unsupervised technique, a conditional variational autoencoder, and validated using vertical-cavity surface-emitting laser (VCSEL) and tunable edge emitting laser reliability data. The experimental results confirm that our model (i) achieves a good degradation prediction and generalization performance by yielding an F1 score of 95.3%, (ii) outperforms several baseline ML based anomaly detection techniques, and (iii) helps to shorten the aging tests by early predicting the failed devices before the end of the test and thereby saving costs

成像，散射和光谱是理解和发现新功能材料的基础。自动化和实验技术的当代创新导致这些测量更快，分辨率更高，从而产生了大量的分析数据。这些创新在用户设施和同步射击光源时特别明显。机器学习（ML）方法经常开发用于实时地处理和解释大型数据集。然而，仍然存在概念障碍，进入设施一般用户社区，通常缺乏ML的专业知识，以及部署ML模型的技术障碍。在此，我们展示了各种原型ML模型，用于在国家同步光源II（NSLS-II）的多个波束线上在飞行分析。我们谨慎地描述这些示例，专注于将模型集成到现有的实验工作流程中，使得读者可以容易地将它们自己的ML技术与具有普通基础设施的NSLS-II或设施的实验中的实验。此处介绍的框架展示了几乎没有努力，多样化的ML型号通过集成到实验编程和数据管理的现有Blueske套件中与反馈回路一起运行。

智能制造系统以越来越多的速度部署，因为它们能够解释各种各样的感知信息并根据系统观察收集的知识采取行动。在许多情况下，智能制造系统的主要目标是快速检测（或预期）失败以降低运营成本并消除停机时间。这通常归结为检测从系统中获取的传感器日期内的异常。智能制造应用域构成了某些显着的技术挑战。特别是，通常有多种具有不同功能和成本的传感器。传感器数据特性随环境或机器的操作点而变化，例如电动机的RPM。因此，必须在工作点附近校准异常检测过程。在本文中，我们分析了从制造测试台部署的传感器中的四个数据集。我们评估了几种基于传统和ML的预测模型的性能，以预测传感器数据的时间序列。然后，考虑到一种传感器的稀疏数据，我们从高数据速率传感器中执行传输学习来执行缺陷类型分类。综上所述，我们表明可以实现预测性故障分类，从而为预测维护铺平了道路。

Concept drift primarily refers to an online supervised learning scenario when the relation between the input data and the target variable changes over time. Assuming a general knowledge of supervised learning in this paper we characterize adaptive learning process, categorize existing strategies for handling concept drift, overview the most representative, distinct and popular techniques and algorithms, discuss evaluation methodology of adaptive algorithms, and present a set of illustrative applications. The survey covers the different facets of concept drift in an integrated way to reflect on the existing scattered state-of-the-art. Thus, it aims at providing a comprehensive introduction to the concept drift adaptation for researchers, industry analysts and practitioners.

现代云计算系统包含数百到数千个计算和存储服务器。这种规模与不断增长的系统复杂性相结合，对可靠云计算的失败和资源管理导致关键挑战。自主失败检测是了解系统级可靠性保证的紧急，云现象和自我管理云资源的重要技术。要检测到失败，我们需要监控云执行并收集运行时性能数据。这些数据通常是未标记的，因此在生产云中并不总是可用的现有故障历史。在本文中，我们提出了一种\ emph {自我不断发展的异常检测}（SEAD）框架，用于云可靠性保证。我们的框架通过递归探索新验证的异常记录并在线持续更新异常探测器。作为我们框架的鲜明优势，云系统管理员只需要检查少量检测到的异常，并且它们的决定可以利用以更新探测器。因此，探测器在升级系统硬件，软件堆栈的更新和用户工作负载的更改之后演变。此外，我们设计了两种类型的探测器，一个用于一般异常检测，另一类用于特异性异常检测。在自我不断发展的技术的帮助下，我们的探测器可以平均达到88.94 \％的灵敏度和94.60 \％，这使得它们适合现实世界部署。

使用最后一英里无线连接的终端设备的数量随着智能基础设施的上升而大大增加，并且需要可靠的功能来支持平滑和高效的业务流程。为了有效地管理此类大规模无线网络，需要更先进和准确的网络监控和故障检测解决方案。在本文中，我们使用复制图和克朗尼亚角场进行无线异常检测的基于图像的表示技术的第一次分析，并提出了一种启用精确异常检测的新的深度学习架构。我们详细阐述了开发资源意识架构的设计考虑因素，并使用时间序列提出新模型以使用复制图来实现图像转换。我们表明，所提出的模型a）以最多14个百分点的基于语法角字段优异的型号，b）使用动态时间翘曲高达24个百分点，c）优于24个百分点的典型ML模型，C）优于或与主流架构相表现出如AlexNet和VGG11的同时具有<10倍的权重和高达$ \其计算复杂度的8倍，而d）优于各个应用面积的最新状态高达55个百分点。最后，我们还在随机选择的示例上解释了分类器如何决定。

Anomaly detection is an active research topic in many different fields such as intrusion detection, network monitoring, system health monitoring, IoT healthcare, etc. However, many existing anomaly detection approaches require either human intervention or domain knowledge, and may suffer from high computation complexity, consequently hindering their applicability in real-world scenarios. Therefore, a lightweight and ready-to-go approach that is able to detect anomalies in real-time is highly sought-after. Such an approach could be easily and immediately applied to perform time series anomaly detection on any commodity machine. The approach could provide timely anomaly alerts and by that enable appropriate countermeasures to be undertaken as early as possible. With these goals in mind, this paper introduces ReRe, which is a Real-time Ready-to-go proactive Anomaly Detection algorithm for streaming time series. ReRe employs two lightweight Long Short-Term Memory (LSTM) models to predict and jointly determine whether or not an upcoming data point is anomalous based on short-term historical data points and two long-term self-adaptive thresholds. Experiments based on real-world time-series datasets demonstrate the good performance of ReRe in real-time anomaly detection without requiring human intervention or domain knowledge.

Unsupervised anomaly detection in time-series has been extensively investigated in the literature. Notwithstanding the relevance of this topic in numerous application fields, a complete and extensive evaluation of recent state-of-the-art techniques is still missing. Few efforts have been made to compare existing unsupervised time-series anomaly detection methods rigorously. However, only standard performance metrics, namely precision, recall, and F1-score are usually considered. Essential aspects for assessing their practical relevance are therefore neglected. This paper proposes an original and in-depth evaluation study of recent unsupervised anomaly detection techniques in time-series. Instead of relying solely on standard performance metrics, additional yet informative metrics and protocols are taken into account. In particular, (1) more elaborate performance metrics specifically tailored for time-series are used; (2) the model size and the model stability are studied; (3) an analysis of the tested approaches with respect to the anomaly type is provided; and (4) a clear and unique protocol is followed for all experiments. Overall, this extensive analysis aims to assess the maturity of state-of-the-art time-series anomaly detection, give insights regarding their applicability under real-world setups and provide to the community a more complete evaluation protocol.

The detection of anomalies in time series data is crucial in a wide range of applications, such as system monitoring, health care or cyber security. While the vast number of available methods makes selecting the right method for a certain application hard enough, different methods have different strengths, e.g. regarding the type of anomalies they are able to find. In this work, we compare six unsupervised anomaly detection methods with different complexities to answer the questions: Are the more complex methods usually performing better? And are there specific anomaly types that those method are tailored to? The comparison is done on the UCR anomaly archive, a recent benchmark dataset for anomaly detection. We compare the six methods by analyzing the experimental results on a dataset- and anomaly type level after tuning the necessary hyperparameter for each method. Additionally we examine the ability of individual methods to incorporate prior knowledge about the anomalies and analyse the differences of point-wise and sequence wise features. We show with broad experiments, that the classical machine learning methods show a superior performance compared to the deep learning methods across a wide range of anomaly types.

燃气轮机发动机是复杂的机器，通常产生大量数据，并且需要仔细监控，以允许具有成本效益的预防性维护。在航空航天应用中，将所有测量数据返回到地面是昂贵的，通常会导致有用，高值，要丢弃的数据。因此，在实时检测，优先级和返回有用数据的能力是至关重要的。本文提出了由卷积神经网络常态模型描述的系统输出测量，实时优先考虑预防性维护决策者。由于燃气轮机发动机时变行为的复杂性，导出精确的物理模型难以困难，并且通常导致预测精度低的模型和与实时执行不相容。数据驱动的建模是一种理想的替代方案，生产高精度，资产特定模型，而无需从第一原理推导。我们提出了一种用于在线检测和异常数据的优先级的数据驱动系统。通过集成到深神经预测模型中的不确定管理，避免了偏离新的操作条件的数据评估。测试是对实际和合成数据进行的，显示对真实和合成故障的敏感性。该系统能够在低功耗嵌入式硬件上实时运行，目前正在部署Rolls-Royce Pearl 15发动机飞行试验。