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Transformer Health Monitoring Using Dissolved Gas Analysis 利用溶解气体分析进行变压器健康监测
IF 2.1 Q2 Engineering Pub Date : 2022-07-12 DOI: 10.36001/ijphm.2022.v13i2.3141
C. Walker, Ahmad Y. Al Rashdan, V. Agarwal
As integral components of any power plant, transformers sup-ply the generated electricity to the grid. However, the trans-former’s cellulose-based paper insulation and the mineral oilin which it is immersed break down over time under stan-dard operating conditions—or more rapidly due to potentialfaults within the system. This technical brief exhibits a col-lection of diagnostic and prognostic techniques that utilitiescan adopted in lieu of labor-intense periodic preventive main-tenance routines. Furthermore, prognostic models have beenincorporated using the latest version of the Institute of Elec-trical and Electronics Engineers (IEEE) standard (IEEE StdC57.104TM-2019) for dissolved gas analysis (DGA), thusexpanding it to include estimation of the time to maintenance.Overall, four different methodologies are explained, each ofwhich aid in determining a transformer’s state of health. Thesemethodologies include the Chendong model, the IEEE C57.91-2011 thermal life consumption model, a diagnostic model forDGA, and a prognostic model for DGA that uses an autore-gressive integrated moving average (ARIMA) model. An ad-ditional improvement for estimating missing system parame-ters from monitoring data (i.e., a tool for parameter estimationutilizing Powell’s method) is presented, enabling the IEEEthermal life consumption model to benefit not only the col-laborating power plant, but also the power industry at large.
作为任何发电厂的组成部分,变压器向电网提供发电。然而,在标准操作条件下,变压器的纤维素基绝缘纸和浸入其中的矿物油会随着时间的推移而分解,或者由于系统内的潜在故障而更快地分解。本技术简介展示了诊断和预后技术的集合,公用事业公司可以采用这些技术来代替劳动密集型的定期预防性维护程序。此外,使用最新版本的电气和电子工程师协会(IEEE)标准(IEEE StdC57.104TM-2019)纳入了预测模型,用于溶解气体分析(DGA),从而将其扩展到包括维护时间的估计。总的来说,解释了四种不同的方法,每一种方法都有助于确定变压器的健康状态。这些方法包括陈东模型、IEEE C57.91-2011热寿命消耗模型、诊断模型forDGA和使用自回归综合移动平均(ARIMA)模型的DGA预测模型。提出了从监测数据中估计缺失系统参数的额外改进(即利用Powell方法进行参数估计的工具),使ieee热寿命消耗模型不仅有利于合作电厂,而且有利于整个电力工业。
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引用次数: 0
Model-based Fusion of Surface Electromyography with Kinematic and Kinetic Measurements for Monitoring of Muscle Fatigue 基于模型的表面肌电图与运动学和动力学测量的融合监测肌肉疲劳
IF 2.1 Q2 Engineering Pub Date : 2022-07-07 DOI: 10.36001/ijphm.2022.v13i2.3132
Haihua Ou, D. Gates, S. Johnson, D. Djurdjanović
This study proposes a novel method for monitoring muscle fatigue using muscle-specific dynamic models which relate joint time-frequency signatures extracted from the relevant electromyogram (EMG) signals with the corresponding estimated muscle forces. Muscle forces were estimated using physics-driven musculoskeletal models which incorporate muscle lengths and contraction velocities estimated from the available kinematic and kinetic measurements. For any specific individual, such a muscle-specific dynamic model is trained using EMG and movement data collected in the early stages of an exercise, i.e., during the least-fatigued behavior. As the exercise or physical activity of that individual progresses and fatigue develops, residuals yielded by that model when approximating the newly arrived data shift and change because of the fatigue-induced changes in the underlying dynamics. In this paper, we propose quantitative evaluation of those changes via the concept of a muscle-specific Freshness Index (FI) which at any given time expresses overlaps between the distribution of that muscle’s model residuals observed on the most recently collected data and the distribution of modeling residuals observed during non-fatigued behavior. The newly proposed method was evaluated using data collected during a repetitive sawing motion experiment with 12 healthy participants. The performance of the FI as a fatigue metric was compared with the performance of the instantaneous frequency of the relevant EMG signals, which is a more traditional and widely used metric of muscle fatigue. It was found that the FI reflected the progression of muscle fatigue with desirable properties of stronger monotonic trends and smaller noise levels compared to the traditional, instantaneous frequency-based metrics.
这项研究提出了一种使用特定肌肉动力学模型监测肌肉疲劳的新方法,该模型将从相关肌电图(EMG)信号中提取的关节时频特征与相应的估计肌肉力量相关联。使用物理驱动的肌肉骨骼模型来估计肌肉力量,该模型结合了根据可用的运动学和动力学测量估计的肌肉长度和收缩速度。对于任何特定的个体,使用在锻炼的早期阶段,即在最不疲劳的行为期间收集的EMG和运动数据来训练这种肌肉特定的动态模型。随着该个体的锻炼或身体活动的进展和疲劳的发展,该模型在近似新到达的数据时产生的残差会由于疲劳引起的潜在动力学变化而发生变化。在本文中,我们建议通过肌肉特异性新鲜度指数(FI)的概念对这些变化进行定量评估,该指数在任何给定时间都表示在最近收集的数据上观察到的肌肉模型残差的分布与在非疲劳行为期间观察到的建模残差的分布之间的重叠。使用在12名健康参与者的重复锯切运动实验中收集的数据对新提出的方法进行了评估。将FI作为疲劳指标的性能与相关EMG信号的瞬时频率的性能进行了比较,后者是一种更传统且广泛使用的肌肉疲劳指标。研究发现,与传统的基于瞬时频率的指标相比,FI反映了肌肉疲劳的进展,具有更强的单调趋势和更小的噪声水平的理想特性。
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引用次数: 1
Review for State-of-the-Art Health Monitoring Technologies on Airframe Fuel Pumps 机身燃油泵健康监测技术综述
IF 2.1 Q2 Engineering Pub Date : 2022-06-10 DOI: 10.36001/ijphm.2022.v13i1.3134
Tedja Verhulst, D. Judt, C. Lawson, Yongmann M. Chung, Osama Al-Tayawe, Geoff Ward
Aircraft maintenance is an essential cost borne by the airline. Improving maintenance practices for day-to-day operations can lead to significant financial savings. The benefits of effective maintenance are derived from the avoided costs caused by unexpected breakdowns and from maximising aircraft flight time transporting passengers.  The fuel system is a crucial part of the entire aircraft as it ensures delivery of the fuel to the engine and a key component within this system are the fuel pumps. These airborne fuel pumps are classified between the pumps installed in the airframe fuel system and in the engine fuel system. Past works have investigated the performance characteristics of these pumps during flight, however there are no reviews related to the present Health Monitoring (HM) capabilities under flight conditions. HM refers to the field of diagnosing faults or predicting the remaining useful life (RUL) of the pump and the focus of this review is to highlight the HM technologies suitable for aircraft fuel pumps. This is done by first reviewing the technologies and concepts related to HM of fuel pumps. Second a literature review is carried out on pump and motor faults is carried out, drawing on examples from aerospace and other relevant industries. Section 6: Conclusion, discusses the HM technologies have been applied to aerospace fuel pumps and highlights the gaps in capabilities, based on the findings of the literature review carried out in Section 4: Common Faults and Section 5: HM Sensing Methods to suggest future developments in this field. It was found that there is a large scope for development for the HM airframe fuel pumps, based on reviewing the present state of the art. Furthermore, there are no clear strategies formulated by airframe manufacturers and equipment suppliers to test and implement existing HM solutions to operate under flight conditions. This highlights the need to develop HM in this field and a requirement for further research to allow this technology to be a part of routine aircraft
飞机维修是航空公司承担的基本费用。改善日常运营的维护做法可以节省大量资金。有效维护的好处来自于避免意外故障造成的成本,以及最大限度地延长运送乘客的飞机飞行时间。燃油系统是整个飞机的重要组成部分,因为它确保将燃油输送到发动机,而该系统中的一个关键部件是燃油泵。这些机载燃油泵分为安装在机身燃油系统和发动机燃油系统中的泵。过去的工作已经调查了这些泵在飞行过程中的性能特征,但没有对飞行条件下的当前健康监测(HM)能力进行审查。HM是指诊断故障或预测泵的剩余使用寿命(RUL)的领域,本综述的重点是强调适用于飞机燃油泵的HM技术。这是通过首先回顾与燃油泵HM相关的技术和概念来实现的。其次,借鉴航空航天和其他相关行业的例子,对泵和电机故障进行了文献综述。第6节:结论,根据第4节:常见故障和第5节:HM传感方法中进行的文献综述的结果,讨论了HM技术已应用于航空航天燃料泵,并强调了能力方面的差距,以建议该领域的未来发展。根据对现有技术的回顾,发现HM机身燃油泵有很大的开发空间。此外,机身制造商和设备供应商没有制定明确的战略来测试和实施现有的HM解决方案,以在飞行条件下运行。这突出了在该领域开发HM的必要性,以及进一步研究的要求,以使该技术成为常规飞机的一部分
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引用次数: 5
Development of Short-Term Forecasting Models Using Plant Asset Data and Feature Selection 基于工厂资产数据和特征选择的短期预测模型的建立
IF 2.1 Q2 Engineering Pub Date : 2022-06-08 DOI: 10.36001/ijphm.2022.v13i1.3120
C. Walker, P. Ramuhalli, Vivek Agarwal, N. Lybeck, Mike Taylor
Nuclear power plants collect and store large volumes of heterogeneous data from various components and systems. With recent advances in machine learning (ML) techniques, these data can be leveraged to develop diagnostic and short-term forecasting models to better predict future equipment condition. Maintenance operations can then be planned in advance whenever degraded performance is predicted, thus resulting in fewer unplanned outages and the optimization of maintenance activities. This enables lower maintenance costs and improves the overall economics of nuclear power. This paper focuses on developing a short-term forecasting process that leverages a feature selection process to distill large volumes of heterogeneous data and predict specific equipment parameters. A variety of feature selection methods, including Shapley Additive Explanations (SHAP) and variance inflation factor (VIF), were used to select the optimal features as inputs for three ML methods: long short-term memory (LSTM) networks, support vector regression (SVR), and random forest (RF). Each combination of model and input features was used to predict a pump bearing temperature both 1 and 24 hours in advance, based on actual plant system data. The optimal inputs for the LSTM and SVR were selected using the SHAP values, while the optimal input for the RF consisted solely of the response variable itself. Each model produced similar 1-hour-ahead predictions, with root mean square errors (RMSEs) of roughly 0.006. For the 24-hour-ahead predictions, differences could be seen between LSTM, SVR, and RF, as reflected by model performances of 0.036 +- 0.014, 0.0026 +- 0, and 0.063 +- 0.004 RMSE, respectively. As big data and continuous online monitoring become more widely available, the proposed feature selection process can be used for many applications beyond the prediction of process parameters within nuclear infrastructure.
核电站从各种组件和系统中收集和存储大量异构数据。随着机器学习(ML)技术的最新进展,这些数据可以用来开发诊断和短期预测模型,以更好地预测未来的设备状况。然后,只要预测到性能下降,就可以提前计划维护操作,从而减少计划外停机并优化维护活动。这降低了维护成本,提高了核电的整体经济性。本文的重点是开发一种短期预测过程,该过程利用特征选择过程提取大量异构数据并预测特定的设备参数。采用Shapley加性解释(SHAP)和方差膨胀因子(VIF)等多种特征选择方法,为长短期记忆(LSTM)网络、支持向量回归(SVR)和随机森林(RF)三种机器学习方法选择最优特征作为输入。模型和输入特征的每种组合都用于根据实际工厂系统数据提前1小时和24小时预测泵轴承温度。LSTM和SVR的最佳输入是使用SHAP值选择的,而RF的最佳输入仅由响应变量本身组成。每个模型都产生了类似的1小时前预测,均方根误差(rmse)大约为0.006。对于24小时前的预测,LSTM、SVR和RF之间存在差异,模型性能分别为0.036 +- 0.014、0.0026 +- 0和0.063 +- 0.004 RMSE。随着大数据和连续在线监测变得越来越广泛,所提出的特征选择过程可以用于核基础设施过程参数预测之外的许多应用。
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引用次数: 1
Development of a Model for Predicting Brake Friction Lining Thickness and Brake Temperature 制动摩擦衬垫厚度和制动温度预测模型的建立
IF 2.1 Q2 Engineering Pub Date : 2022-05-31 DOI: 10.36001/ijphm.2022.v13i1.3064
Rushikesh Pawar, R. Patil, Dhananjay Y. Patil, Aditi Rahegaonkar, S. Pardeshi, A. Patange
Road traffic injuries and deaths are a growing public health concern worldwide, majorly in developing countries. Brake failure constitutes to be one of the primary reasons for accidents. The majority of brake failures are caused due to overheating of the brakes, while wear of lining is another big share-holder. Early detection of such causes can prevent these accidents. This study puts forth a model that can be used for onboard monitoring of drum/disc temperature & lining/pad thickness by taking velocity & road inclination in real-time as inputs. Many quantities are interdependent and vary with respect to time/temperature. Therefore, an incremental approach is used. The model is implemented in the Simulink software. Many standard profiles are also fed to compare results for different terrains and driving conditions. The drivers can also be classified based on their driving behavior. The thermal model can give us an early warning about the brake overheating. This model can be used to study the energy distribution while braking. Researchers and designers can also use this model to study & optimize the brake system.
道路交通伤亡是全世界日益关注的公共卫生问题,尤其是在发展中国家。刹车失灵是造成事故的主要原因之一。大多数制动器故障是由制动器过热引起的,而衬片磨损是另一大原因。及早发现这些原因可以防止这些事故的发生。本研究提出了一个模型,该模型可用于以速度和道路倾斜度作为实时输入的滚筒/圆盘温度和内衬/衬垫厚度的车载监测。许多量是相互依存的,并且随时间/温度而变化。因此,采用了增量方法。该模型在Simulink软件中实现。还提供了许多标准剖面,以比较不同地形和驾驶条件下的结果。驾驶员也可以根据他们的驾驶行为进行分类。热模型可以为我们提供有关制动器过热的早期警告。该模型可用于研究制动时的能量分布。研究人员和设计师也可以使用这个模型来研究和优化制动系统。
{"title":"Development of a Model for Predicting Brake Friction Lining Thickness and Brake Temperature","authors":"Rushikesh Pawar, R. Patil, Dhananjay Y. Patil, Aditi Rahegaonkar, S. Pardeshi, A. Patange","doi":"10.36001/ijphm.2022.v13i1.3064","DOIUrl":"https://doi.org/10.36001/ijphm.2022.v13i1.3064","url":null,"abstract":"Road traffic injuries and deaths are a growing public health concern worldwide, majorly in developing countries. Brake failure constitutes to be one of the primary reasons for accidents. The majority of brake failures are caused due to overheating of the brakes, while wear of lining is another big share-holder. Early detection of such causes can prevent these accidents. This study puts forth a model that can be used for onboard monitoring of drum/disc temperature & lining/pad thickness by taking velocity & road inclination in real-time as inputs. Many quantities are interdependent and vary with respect to time/temperature. Therefore, an incremental approach is used. The model is implemented in the Simulink software. Many standard profiles are also fed to compare results for different terrains and driving conditions. The drivers can also be classified based on their driving behavior. The thermal model can give us an early warning about the brake overheating. This model can be used to study the energy distribution while braking. Researchers and designers can also use this model to study & optimize the brake system.","PeriodicalId":42100,"journal":{"name":"International Journal of Prognostics and Health Management","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46626298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Long-term Evaluation of the State-of-Health of Traction Lithium-ion Batteries in Operational Buses 运行客车牵引锂离子电池健康状况的长期评价
IF 2.1 Q2 Engineering Pub Date : 2022-05-30 DOI: 10.36001/ijphm.2022.v13i1.3115
Miguel Simão, Rune Prytz, Sławomir Nowaczyk
In this paper, we present and evaluate a novel methodology to estimate the usable capacity and state-of-health (SOH) of lithium-ion batteries in battery-electric buses (BEV). This methodology is designed to be applicable to any BEV in normal operation, independently of battery chemistry, and without requiring complex electrochemical models or large data sets. We have tested the proposed methodology on two vehicle fleets with a total of 105 vehicles, for which we have been acquiring data for up to three years. Additionally, we have analysed the operation of the fleets in terms of daily distance driven and the charging strategies chosen by the operators.The monitored vehicles are part of fleets currently in normal operation in Europe. The data collection is done with a third-party data logger that is connected to the vehicles’ Communication Area Network (CAN) buses, and no additional changes were made to the vehicle’s hardware or software. The results show that the proposed methodology shows significantly lower variance in SOH estimation than the alternative methodologies. It also shows similar accuracy in the long-term and smaller short-term deviations from the typical capacity fade model.
在本文中,我们提出并评估了一种估算纯电动公交车(BEV)锂离子电池可用容量和健康状态(SOH)的新方法。该方法适用于任何正常运行的纯电动汽车,独立于电池化学性质,不需要复杂的电化学模型或大型数据集。我们已在两个车队(共105辆车)上测试了建议的方法,并收集了长达三年的数据。此外,我们还分析了车队的日常行驶距离和运营商选择的收费策略。受监控的车辆是目前在欧洲正常运行的车队的一部分。数据收集由第三方数据记录仪完成,该记录仪连接到车辆的通信区域网络(CAN)总线,无需对车辆的硬件或软件进行额外更改。结果表明,所提出的方法在SOH估计上的方差显著低于替代方法。与典型的容量衰减模型相比,它在长期和短期偏差上也显示出相似的准确性。
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引用次数: 1
Emergence of Machine Learning Techniques in Ultrasonic Guided Wave-based Structural Health Monitoring 基于超声导波的结构健康监测中机器学习技术的出现
IF 2.1 Q2 Engineering Pub Date : 2022-05-23 DOI: 10.36001/ijphm.2022.v13i1.3107
A. Sattarifar, T. Nestorović
Identification of damage in its early stage can have a great contribution in decreasing the maintenance costs and prolonging the life of valuable structures. Although conventional damage detection techniques have a mature background, their widespread application in industrial practice is still missing. In recent years the application of Machine Learning (ML) algorithms have been more and more exploited in structural health monitoring systems (SHM). Because of the superior capabilities of ML approaches in recognizing and classifying available patterns in a dataset, they have demonstrated a significant improvement in traditional damage identification algorithms. This review study focuses on the use of machine learning (ML) approaches in Ultrasonic Guided Wave (UGW)-based SHM, in which a structure is continually monitored using permanent sensors. Accordingly, multiple steps required for performing damage detection through UGWs are stated. Moreover, it is outlined that the employment of ML techniques for UGW-based damage detection can be subtended into two main phases: (1) extracting features from the data set, and reducing the dimension of the data space, (2) processing the patterns for revealing patterns, and classification of instances. With this regard, the most frequent techniques for the realization of those two phases are elaborated. This study shows the great potential of ML algorithms to assist and enhance UGW-based damage detection algorithms.
早期识别损伤对降低维修成本、延长有价值结构的使用寿命具有重要意义。传统的损伤检测技术虽有成熟的背景,但在工业实践中仍缺乏广泛的应用。近年来,机器学习(ML)算法在结构健康监测系统(SHM)中的应用越来越广泛。由于机器学习方法在识别和分类数据集中可用模式方面的卓越能力,它们已经证明了传统损伤识别算法的显着改进。本综述研究的重点是在基于超声导波(UGW)的SHM中使用机器学习(ML)方法,其中使用永久性传感器连续监测结构。据此,阐述了通过ugw进行损伤检测所需的多个步骤。此外,本文还概述了使用ML技术进行基于ugw的损伤检测可以分为两个主要阶段:(1)从数据集中提取特征,并降低数据空间的维数;(2)处理模式以揭示模式,并对实例进行分类。在这方面,阐述了实现这两个阶段的最常用技术。这项研究显示了机器学习算法在辅助和增强基于ugw的损伤检测算法方面的巨大潜力。
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引用次数: 4
Optimal Maintenance Policy for Corroded Oil and Gas Pipelines using Markov Decision Processes 基于马尔可夫决策过程的腐蚀油气管道最优维护策略研究
IF 2.1 Q2 Engineering Pub Date : 2022-03-13 DOI: 10.36001/ijphm.2022.v13i1.3106
Roohollah Heidarydashtarjandi, Jubilee Prasad-Rao, K. Groth
This paper presents a novel approach to determine optimal maintenance policies for degraded oil and gas pipelines due to internal pitting corrosion. This approach builds a bridge between Markov process-based corrosion rate models and Markov decision processes (MDP). This bridging allows for the consideration of both short-term and long-term costs for optimal pipeline maintenance operations. To implement MDP, probability transition matrices are estimated to move from one degradation state to the next in the pipeline degradation Markov processes. A case study is also implemented with four pipeline failure modes (i.e., safe, small leak, large leak, and rupture). And four maintenance actions (i.e. do nothing, adding corrosion inhibitors, pigging, and replacement) are considered by assuming perfect pipeline inspections. Monte Carlo simulation is performed on 10,000 initial pits using the selected corrosion models and assumed maintenance and failure costs to determine an optimal maintenance policy.
本文提出了一种新的方法来确定因内部点蚀而退化的油气管道的最佳维护策略。该方法在基于马尔可夫过程的腐蚀速率模型和马尔可夫决策过程(MDP)之间架起了一座桥梁。这种桥接可以考虑最佳管道维护操作的短期和长期成本。为了实现MDP,在流水线退化马尔可夫过程中,估计概率转移矩阵从一个退化状态移动到下一个。还对四种管道故障模式(即安全、小泄漏、大泄漏和破裂)进行了案例研究。假设管道检查完美,则应考虑四种维护措施(即不采取任何措施、添加缓蚀剂、清管和更换)。使用选定的腐蚀模型和假设的维护和故障成本,对10000个初始坑进行蒙特卡罗模拟,以确定最佳维护策略。
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引用次数: 3
Long-Term Modeling and Monitoring of Neuromusculoskeletal System Performance Using Tattoo-Like EMG Sensors 使用纹身样肌电传感器的神经肌肉骨骼系统性能的长期建模和监测
IF 2.1 Q2 Engineering Pub Date : 2022-02-20 DOI: 10.36001/ijphm.2019.v10i3.2705
Kai-Wen Yang, L. Nicolini, Irene Kuang, N. Lu, D. Djurdjanović
This paper introduces stretchable, long-term wearable, tattoo-like dry surface electrodes for highly repeatable electromyography (EMG). The tattoo-like sensors are hair thin, skin compliant and can be laminated on human skin just like a temporary transfer tattoo, which enables multi-day noninvasive but intimate contact with the skin even under severe skin deformation. The new electrodes were used to facilitate a system-based approach to tracking of long-term fatiguing and recovery processes in a human neuromusculoskeletal (NMS) system, which was based on establishing an autoregressive moving average model with exogenous inputs (ARMAX model) relating signatures extracted from the surface electromyogram (sEMG) signals collected using the tattoo-like sensors, and the corresponding hand grip force (HGF) serving as the model output. Performance degradation of the relevant NMS system was evaluated by tracking the evolution of the errors of the ARMAX model established using the data corresponding to the rested (fresh) state of any given subject. Results from several exercise sessions clearly showed repeated patterns of fatiguing and resting, with a notable point that these patterns could now be quantified via dynamic models relating the relevant muscle signatures and NMS outputs.
本文介绍了一种可拉伸的、长期可穿戴的、纹身状的干表面电极,用于高度可重复的肌电图(EMG)。这种像纹身一样的传感器只有头发那么细,皮肤很柔韧,可以像临时转移纹身一样叠在人体皮肤上,即使在皮肤严重变形的情况下,也能与皮肤进行多天的无创亲密接触。新电极用于促进基于系统的方法来跟踪人类神经肌肉骨骼(NMS)系统的长期疲劳和恢复过程,该方法基于建立一个带有外源输入的自回归移动平均模型(ARMAX模型),该模型与使用纹身样传感器收集的表面肌电图(sEMG)信号提取的特征相关,并将相应的手握力(HGF)作为模型输出。通过跟踪任意给定受试者的休息(新鲜)状态数据所建立的ARMAX模型的误差演变来评估相关NMS系统的性能退化。几次锻炼的结果清楚地显示了疲劳和休息的重复模式,值得注意的是,这些模式现在可以通过与相关肌肉特征和NMS输出相关的动态模型来量化。
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引用次数: 4
Remaining Useful Life Prognosis of Aircraft Brakes 飞机制动器剩余使用寿命预测
IF 2.1 Q2 Engineering Pub Date : 2022-01-25 DOI: 10.36001/ijphm.2022.v13i1.3072
T. Loutas, Athanasios Oikonomou, N. Eleftheroglou, F. Freeman, D. Zarouchas
We investigate the performance of three different data-driven prognostic methodologies towards the Remaining Useful Life estimation of commercial aircraft brakes being continuously monitored for wear. The first approach utilizes a probabilistic multi-state deterioration mathematical model i.e. a Hidden Semi Markov model whilst the second utilizes a nonlinear regression approach through classical Artificial Neural Networks in a Bootstrap fashion in order to obtain prediction intervals to accompany the mean remaining life estimates. The third approach attempts to leverage the highly linear degradation data over time and uses a simple linear regression in a Bayesian framework. All methodologies, when properly trained with historical degradation data, achieve excellent performance in terms of early and accurate prediction of the remaining useful flights that the monitored set of brakes can safely serve. The paper presents a real-world application where it is demonstrated that even in non-complex linear degradation data the inherent data stochasticity prohibits the use of a simple mathematical approaches and asks for methodologies with uncertainty quantification.
我们研究了三种不同的数据驱动预测方法在持续监测磨损情况的商用飞机制动器剩余使用寿命估计方面的性能。第一种方法利用概率多状态恶化数学模型,即隐半马尔可夫模型,而第二种方法通过Bootstrap方式的经典人工神经网络利用非线性回归方法,以获得伴随平均剩余寿命估计的预测区间。第三种方法试图利用随时间变化的高度线性退化数据,并在贝叶斯框架中使用简单的线性回归。当使用历史退化数据进行适当训练时,所有方法都能在早期准确预测被监测的刹车组可以安全服务的剩余有用飞行方面取得优异的性能。本文介绍了一个真实世界的应用,证明了即使在非复杂的线性退化数据中,固有的数据随机性也禁止使用简单的数学方法,并要求使用具有不确定性量化的方法。
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引用次数: 7
期刊
International Journal of Prognostics and Health Management
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