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Digital twin-assisted gearbox dynamic model updating toward fault diagnosis

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机械工程前沿:英文版 2023年第2期18卷 283-296页

作者： jingyan xia Ruyi HUANG Yixiao LIAO Jipu LI Zhuyun CHEN Weihua LI School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou 511442China Guangdong Artificial Intelligence and Digital Economy Laboratory(Guangzhou) Guangzhou 510335China

One of the core challenges of intelligent fault diagnosis is that the diagnosis model requires numerous labeled training datasets to achieve satisfactory *** training data using a virtual model is a potential solution for addressing such a problem,and the construction of a high-fidelity virtual model is fundamental and critical for data *** this study,a digital twin-assisted dynamic model updating method for fault diagnosis is thus proposed to improve the fidelity and reliability of a virtual model,which can enhance the generated data ***,a virtual model is established to mirror the vibration response of a physical entity using a dynamic modeling ***,the modeling method is validated through a frequency analysis of the generated ***,based on the signal similarity indicator,a physical–virtual signal interaction method is proposed to dynamically update the virtual model in which parameter sensitivity analysis,surrogate technique,and optimization algorithm are applied to increase the efficiency during the model ***,the proposed method is successfully applied to the dynamic model updating of a single-stage helical gearbox;the virtual data generated by this model can be used for gear fault diagnosis.

关键词： digital twin gearbox model construction model updating physical-virtual interaction

The determination of sedimentary environment and associated energy in deep-buried marine carbonates:insights from natural gamma ray spectrometry log

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Frontiers of Earth Science 2024年第1期18卷 204-218页

作者： jingyan LIU Qian CHANG Junlong ZHANG Hui CHAI Feng HE Yizan YANG Shiqiang xia School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Exploration and Development Research Institute Daqing Oilfield CompanyPetroChinaDaqing 163712China China National Oil and Gas Exploration and Development Co. Ltd(CNODC)Beijing 100032China Beijing Research Institute of Uranium Geology Beijing 100029China College of Mining Engineering North China University of Science and TechnologyTangshan 063210China

It has always been challenging to determine the ancient sedimentary environment and associated energy in deep-buried marine *** energy represents the hydrodynamic conditions that existed when the carbonates were *** energy includes light and chemical energies in compounds and kinetic energy in currents and mass ***-buried marine carbonates deposited during the Ordovician depositional period in the eastern Tarim Basin result from a complex interplay of tectonics,sedimentation,and *** a result,determining the ancient sedimentary environment and associated energy is *** natural gamma-ray spectrometry(GRS)log(from 12 wells)is used in this paper to conduct studies on the sedimentary environment and associated energy in deep-buried marine *** findings show that the values of thorium(Th),uranium(U),potassium(K),and gamma-ray without uranium(KTh)in a natural GRS log can reveal lithological associations,mineral composition,diagenetic environment,stratigraphic water activity,and ancient climatic *** the Ordovician,quantitative analysis and determination of sedimentary environment energy are carried out using a comprehensive calculation of natural GRS log parameters in typical wells(penetrating through the Ordovician with cores and thin sections)of well GC4,well GC6,well GC7,and well *** results show that GRS log can determine different lithology associations in typical wells than a sieve residue ***,cores and thin sections can be used to validate the determination of lithology *** on the determination of lithology associations,the lithology associations that reflect the sedimentary environment and associated energy can be analyzed in a new ***,the sedimentary environment energy curve derived from a natural GRS log can reveal hydrodynamic fluctuations during depositional periods,which will aid in the discovery of carbonate reservoirs,establishing sequence stratigra

关键词： ancient sedimentary environment energy of sedimentary environment marine deep-buried carbonates natural GRS the Ordovician eastern Tarim Basin

Impact of vitamin D supplementation on the outcome of tuberculosis treatment： a systematic review and meta-analysis of randomized controlled trials

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Chinese Medical Journal 2014年第17期127卷 3127-3134页

作者： xia jingyan Shi Liyun Zhao Lifang Xu Feng Department of Radiation Oncology Second Affiliated HospitalZhejiang University School of Medicine Hangzhou Zhejiang310009 China Division of Immunology Hangzhou Normal University Hangzhou Zhejiang 310036 China Department ofInfectious Diseases Second Affiliated HospitalZhejiang University School of Medicine Hangzhou Zhejiang310009 China

Background Vitamin D supplementation is believed to be beneficial in the treatment of patients with tuberculosis （TB）,however,results from clinical trials have been *** We performed a systematic literature search across MEDLINE,EMBASE,the Cochrane Central Register of Controlled Trials,Springer,EBSCO,ProQuest,HighWire Press,and Web of Science,published as of December *** individually inspected citations and extracted data *** estimated pooled risk ratios （RR） and 95％ confidence intervals （CI） using random-effect *** also assessed risk of bias using the Jadad scale and the quality of the evidence using *** included all randomized controlled trials comparing vitamin D with or without standard TB therapy or *** A total of five studies were analyzed in our meta analysis covering 841 newly-diagnosed TB *** receiving vitamin D supplementation had a 39％ reduced risk of sputum smear or culture positive after six weeks of antiTB treatment than those in the control group,although this is not statistically significant （pooled RR 0.61,95％ CI 0.24 to 1.56,P=0.30）.Apart from an increased serum vitamin D level in the supplement group after eight weeks of treatment there was no evidence of any additional adverse effects related to vitamin *** The meta analysis results indicate that vitamin D supplementation does not seem to have any beneficial effect in the treatment of *** rigorous randomized controlled trials are needed to explore whether the supplementation of vitamin D could shorten treatment duration and to confirm whether the polymorphisms of vitamin D receptor have any potentially beneficial effect.

关键词： tuberculosis vitamin D randomized controlled trials systematic review meta-analysis

Compound Fault Diagnosis for Rotating Machinery:State-of-the-Art,Challenges,and Opportunities

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Journal of Dynamics, Monitoring and Diagnostics 2023年第1期2卷 13-29页

作者： Ruyi Huang jingyan xia Bin Zhang Zhuyun Chen Weihua Li Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou 510640China PazhouLab Guangzhou 510335China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China

Compound fault,as a primary failure leading to unexpected downtime of rotating machinery,dramatically increases the difficulty in fault *** deal with the difficulty encountered in implementing compound fault diagnosis(CFD),researchers and engineers from industry and academia have made numerous significant breakthroughs in recent ***,many systematic surveys focused on fault diagnosis have been conducted by reputable ***,previous review articles paid more attention to fault diagnosis with several single or independent faults,resulting in that there is still lacking a comprehensive survey on ***,to fulfill the above requirements,it is necessary to provide an in-depth overview of fault diagnosis methods or algorithms for compound faults of rotating machinery and uncover potential challenges or opportunities that would guide and inspire readers to devote their efforts to promoting fault diagnosis technology more effective and ***,the backgrounds,including the related definitions and a new taxonomy of CFD methods,are detailed according to the way of implementing compound fault ***,the stateof-the-art applications of CFD are overviewed based on relevant publications in the past ***,the challenges and opportunities associated with implementing CFD are concluded and followed by a conclusion for ending this *** believe that this review article can provide a systematic guideline of CFD from different aspects for potential readers and seasoned researchers.

关键词： fault diagnosis compound fault signal processing artificial intelligence rotating machinery

场馆疲劳现象的表现形式、影响因素与缓解策略研究

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科普研究 2023年第1期18卷 51-59,69,107,108页

作者：夏婧妍翟俊卿浙江大学教育学院杭州310058

场馆参观是非正式学习的重要形式,“疲劳的访客”与“访客的疲劳”一直是场馆研究领域的重要议题。场馆疲劳是访客参观过程中的突出现象,自20世纪初就引起学界关注。本文对21世纪以来国外有关场馆疲劳的研究进行回顾,以场馆疲劳的概念... 详细信息

场馆参观是非正式学习的重要形式,“疲劳的访客”与“访客的疲劳”一直是场馆研究领域的重要议题。场馆疲劳是访客参观过程中的突出现象,自20世纪初就引起学界关注。本文对21世纪以来国外有关场馆疲劳的研究进行回顾,以场馆疲劳的概念内涵和产生原因为切入点,揭示导致场馆疲劳的本体因素、感知因素和场域因素,归纳现有研究在测量场馆疲劳方面的方法、局限与改进措施。在此基础上,结合科普场馆本质属性,深入探寻新时代背景下场馆疲劳的缓解路径,具体包括:打造复元结构环境、应用认知建构模式、建立对话反馈机制。研究场馆疲劳对促进科普场馆资源管理和利用具有积极意义。

关键词：场馆疲劳访客研究影响因素测量与评估

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基于选择性加权适配网络的多域新故障识别方法

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仪器仪表学报 2022年第10期43卷 270-279页

作者：陈祝云林慧斌夏景演晋刚李巍华华南理工大学机械与汽车工程学院广州511442 琶洲实验室广州510005 北京信息科技大学重点科研机构北京100192 华南理工大学吴贤铭智能工程学院广州511442

针对深度迁移学习诊断方法要求机械设备训练数据与测试数据具有相同类别空间,同时难以有效识别新故障的问题,提出了一种基于选择性加权适配网络的多域新故障识别方法。所提方法利用一维卷积神经网络提取源域与目标域深度判别特征,并集... 详细信息

针对深度迁移学习诊断方法要求机械设备训练数据与测试数据具有相同类别空间,同时难以有效识别新故障的问题,提出了一种基于选择性加权适配网络的多域新故障识别方法。所提方法利用一维卷积神经网络提取源域与目标域深度判别特征,并集成领域判别器与多分类器结构,构建源域与目标域权重函数,自适应度量源域与目标域类别的相似程度;从而利用对抗学习策略来有效减少源域与目标域共享类数据的分布差异;最后利用高斯分布拟合方法自动判别权重阈值,实现对目标域已知故障和新故障的有效诊断。在齿轮箱变工况迁移诊断任务上对所提方法进行分析与应用验证,并与现有的其它方法进行比较,所提方法在所有任务上的调和平均值(E-score)达到0.8以上,验证了所提方法的有效性与优越性。

关键词：故障诊断对抗学习新故障深度学习迁移学习

孪生数据与特征增强融合驱动的装备小样本诊断方法

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中国科学：技术科学 2023年第7期53卷 1202-1213页

作者：夏景演黄如意陈祝云李霁蒲李巍华华南理工大学机械与汽车工程学院广州510641 人工智能与数字经济广东省实验室(广州) 广州510335 华南理工大学吴贤铭智能工程学院广州511442

近年来,得益于新一代信息技术的快速发展,智能故障诊断技术在航空航天、海洋工程、汽车工业等领域得到了广泛的关注与应用.然而,一方面,智能故障诊断模型在实际应用部署时,面临着故障样本不足的难题,导致所构建的模型诊断可靠性较低;另... 详细信息

近年来,得益于新一代信息技术的快速发展,智能故障诊断技术在航空航天、海洋工程、汽车工业等领域得到了广泛的关注与应用.然而,一方面,智能故障诊断模型在实际应用部署时,面临着故障样本不足的难题,导致所构建的模型诊断可靠性较低;另一方面,现有面向小样本问题的智能诊断方法往往需要相关性较强的实测数据作为支撑,这极大限制了该方法的实用性.基于此,本文提出了一种孪生数据与特征增强融合驱动的机械装备小样本故障诊断方法.首先,构建机械装备的虚拟模型,并结合装备的运行机理知识和健康状态的实测数据对模型进行优化修正,以获取高保真模型,进而基于该模型获取高质量的孪生故障数据;其次,以孪生故障数据为输入,利用生成对抗网络进行装备孪生故障数据的特征增强,并将增强后的数据用于卷积神经网络模型的训练,从而实现装备的智能故障诊断;最后,以某汽车用变速器为研究对象,验证所提方法的可行性.该方法丰富了新一代工业人工智能与大数据分析理论,为现代装备的小样本智能故障诊断提供了一种新的解决思路.

关键词：智能故障诊断数字孪生生成对抗网络小样本机械装备

基于多任务学习的装备智能诊断与寿命预测方法

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中国科学：技术科学 2022年第1期52卷 123-137页

作者：黄如意李霁蒲王震夏景演陈祝云李巍华华南理工大学吴贤铭智能工程学院广州511442 华南理工大学机械与汽车工程学院广州510641 人工智能与数字经济广东省实验室(广州) 广州510335

智能故障诊断与预测性维护技术是推动我国制造业向数字化、网络化、智能化方向发展的关键切入点和实现"弯道超车"的创新动力.得益于人工智能和机器学习技术的快速发展,智能故障诊断与寿命预测方法在航空航天、石油化工、船舶等领域得到... 详细信息

智能故障诊断与预测性维护技术是推动我国制造业向数字化、网络化、智能化方向发展的关键切入点和实现"弯道超车"的创新动力.得益于人工智能和机器学习技术的快速发展,智能故障诊断与寿命预测方法在航空航天、石油化工、船舶等领域得到了广泛的研究与应用.然而,传统智能方法为实现机械装备的初始异常检测、故障诊断与寿命预测等多种任务时,均需逐一地训练检测、诊断与预测多个模型,不仅增加了设备开发、部署与维护的成本,也极大地限制了智能方法的实用性.为解决上述局限性,基于多任务学习,提出一种用于机械装备智能诊断(初始异常检测和故障诊断)与智能寿命预测等多种任务的健康监测方法.首先,利用JS散度(Jensen-Shannon divergence)和相关分析实现设备初始异常检测;其次,结合多任务学习(Multi-task learning)的知识共享机制建立可同时实现故障诊断与寿命预测的智能模型,仅需训练和部署一个模型即可同时获得设备的故障信息与剩余使用寿命信息;最后,利用轴承全寿命加速退化实验数据,通过与领域内先进方法对比,验证了所提方法在初始异常检测、故障诊断与寿命预测等多种任务的有效性和可靠性,为工业设备的智能诊断与预测性维护提供重要的决策依据,具有较强的工程应用价值.

关键词：故障诊断寿命预测初始异常检测多任务学习机械装备

基于天然衍生多糖和蛋白质的促伤口愈合水凝胶

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生物医学转化 2023年第3期4卷 86-96页

作者：胡惠群徐峰夏靖燕浙江大学医学院附属第二医院浙江杭州310009 浙江大学滨江研究院浙江杭州310053

伤口愈合是一种常见的生理过程,在组织病变开始后,一系列分子和细胞事件发生以重建身体和外部环境之间的屏障。水凝胶在伤口治疗中具有显著优势,它们能够对伤口愈合过程进行时空控制,有效促进受损组织在水合环境下愈合。多糖和蛋白质的... 详细信息

伤口愈合是一种常见的生理过程,在组织病变开始后,一系列分子和细胞事件发生以重建身体和外部环境之间的屏障。水凝胶在伤口治疗中具有显著优势,它们能够对伤口愈合过程进行时空控制,有效促进受损组织在水合环境下愈合。多糖和蛋白质的各种突出特征可用做制备仿生多功能水凝胶的有效伤口敷料。结合生物小分子和支持细胞,水凝胶可以进一步发挥更快和更好的愈合功能。本综述主要讨论了天然衍生多糖和蛋白质水凝胶伤口敷料对创面病理生理学的影响,及其理想特性、交联机制和制造技术。

关键词：伤口愈合水凝胶生物小分子多糖蛋白质伤口敷料