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结合CNN和LSTM的滚动轴承剩余使用寿命预测方法

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振动．测试与诊断 2021年第3期41卷 439-446,617页

作者：王玉静李少鹏康守强谢金宝 MiKULOViCH V i 哈尔滨理工大学电气与电子工程学院哈尔滨150080 白俄罗斯国立大学明斯克220030

针对滚动轴承存在性能退化渐变故障和突发故障两种模式下的剩余使用寿命(remaining useful life,简称RUL)预测困难的问题,提出一种结合卷积神经网络(convolution neural networks,简称CNN)和长短时记忆(long short term memory,简称LSTM... 详细信息

针对滚动轴承存在性能退化渐变故障和突发故障两种模式下的剩余使用寿命(remaining useful life,简称RUL)预测困难的问题,提出一种结合卷积神经网络(convolution neural networks,简称CNN)和长短时记忆(long short term memory,简称LSTM)神经网络的滚动轴承RUL预测方法。首先,对滚动轴承原始振动信号作快速傅里叶变换(fast Fourier transform,简称FFT);其次,将预处理所得到的频域幅值信号进行归一化处理后,将其作为CNN的输入,并利用CNN自适应提取局部内在有用信息,学习并挖掘深层特征,避免传统算法需要专家大量经验的弊端;然后,再将深层特征输入到LSTM网络中,构建趋势性量化健康指标,同时确定失效阈值;最后,运用移动平均法进行平滑处理,消除局部振荡,再利用多项式曲线拟合,预测未来失效时刻,实现滚动轴承RUL预测。实验结果表明,所提方法构建的趋势性量化健康指标在两种故障模式下都具有良好的单调趋势性,预测结果能够较好地接近真实寿命值。

关键词：滚动轴承卷积神经网络长短时记忆神经网络趋势性量化健康指标剩余使用寿命预测

Traditional Chinese medicine wrist pulse-taking is associated with pulse waveform analysis and hemodynamics in hypertension

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Journal of integrative Medicine 2016年第2期14卷 100-113页

作者： Nathalia Gomes Ribeiro de Moura ivan Cordovil Arthur de sa Ferreira Postgraduate Program of Rehabilitation Science Augusto Motta University Center21041-010Rio de JaneiroR JBrazil Division of Arterial Hypertension National Institute of Cardiology22240-002Rio de JaneiroR JBrazil Department of Physical Therapy Salgado de Oliveira University24030-060NiteroiR JBrazil

BACKGROUND： Pulse wave analysis（PWA） quantifies the phenomenon of pulse waveform propagation in patients with cardiovascular diseases, whereas pulse image analysis（PiA） is a subjective examination in traditional Chinese medicine. OBJECTiVE： This study evaluated the association of PiA with PWA and hemodynamics in patients with hypertension. DESiGN, SETTiNG, PARTiCiPANTS AND iNTERVENTiONS： This observational, cross-sectional study enrolled 45 patients（26 men,（55.2± 10.3） years, systolic blood pressure（155± 28） mm Hg, diastolic blood pressure（93± 17） mm Hg） for assessment of clinical and laboratorial data. MAiN OUTCOME MEASURES： Primary outcomes comprised： pattern differentiation based on an automated method; PiA at the radial artery using the ‘simultaneous pressing＇ method for identification of factors such as strength（strong/weak）, depth（superficial/deep）, and speed（fast/moderate/slow）; and PWA at the same artery using a noninvasive system. RESULTS： Significant multivariate main effects were observed for depth（l=0.648, F_（5,29）=3.149, P=0.022, h^2 =0.352）, strength（l=0.608, F_（5,29） =3.736, P=0.010, h^2 =0.392）, and speed（l=0.535, F_（5,29） =5.302, P=0.002, h^2 =0.465）. General effects comprised high values of PWA and blood pressure for superficial, strong, and fast pulse images. A strong pulse was found for pulse pressure ≥ 62.5 mm Hg and systolic blood pressure ≥ 149.5 mm Hg, whereas a superficial pulse was found for heart rate ≥ 58.25 beats/min; a fast pulse was found for heart rate ≥ 69.6 beats/min and pulse wave velocity ≥ 9.185 m/s. CONCLUSiON： Associations were explained by La Place＇s law, arterial remodeling in hypertension, alongside the traditional criterion for classifying speed in pulse images. PiA is associated with PWA and hemodynamics in patients with hypertension. Systolic and pulse pressures, heart rate, and pulse wave velocity are quantitative variables that have information to describe the qualitative pulse images such as strength, depth and speed.

关键词： medicine Chinese traditional hypertension syndrome differentiation rehabilitation

Crystallization and Hardness of Melt Spun Fe_(73)Si_(13)B_9Nb_4Cu_1 Alloy

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Journal of Materials Science & Technology 2009年第1期25卷 48-52页

作者： J.i. Akhter M. iqbal M. Siddique M. Ahmad M.A. Haq M.A. Shaikh Z.Q. Hu Physics Division Pakistan Institute of Nuclear Science and Technology P. O. Nilore Islamabad Pakistan Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Chemical and Materials Engineering Pakistan Institute of Engineering and Applied Sciences P.O. Nilore Islamabad Pakistan

An alloy having composition Fe73Si13B9Nb4Cu1 was synthesized by melt spinning to investigate the kinetics of crystallization. Techniques of differential scanning calorimetry （DSC）, X-ray diffraction （XRD） and Mossbauer spectroscopy were employed to characterize the phases produced due to annealing at various temperatures. High temperature DSC revealed two stage crystallization reactions. First stage, crystallization occurs at temperature around 514℃ with the production of α-Fe （bcc） and Fe3Si phases. in the second stage, Fe2B and α-Fe （Si,Nb） phases were produced. Mossbauer results revealed the formation of Fe3Si, Fe13Si3 and Fe7Si1 in the first stage and Fe3Si, Fe13Si3, Fe2B and α-Fe （Si,Nb） phases in the second stage of crystallization. An abrupt change in average internal magnetic field was observed at 500℃. The maximum hardness value was found for the sample heat-treated at 500℃.

关键词： Amorphous alloy Crystallization Mossbauer spectroscopy Hardness

Modelling and reviewing the reliability and multi-objective optimization of wind-turbine system and photovoltaic panel with intelligent algorithms

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Clean Energy 2021年第4期5卷 713-730页

作者： reza Alayi Mehdi Jahangiri John William Grimaldo Guerrero Ravil Akhmadeev Rustem Adamovich Shichiyakh sara Abbasi Zanghaneh Department of Mechanics Germi BranchIslamic Azad UniversityGermiIran Department of Mechanical Engineering Shahrekord BranchIslamic Azad UniversityShahrekordIran Departamento de Energía Universidad de la CostaBarranquillaColombia Plekhanov Russian University of Economics Stremyanny lane36Moscow117997Russian Federation Department of Management Candidate of Economic SciencesKuban State Agrarian University named after I.T.TrubilinKrasnodarRussian Federation Department of Energy Engineering Energy Institute of Higher EducationSavehIran

One of the options for non-dependence on fossil fuels is the use of renewable energy,which has not grown significantly due to the variable nature of this type of *** combined use of wind and solar energy as energy sources can be a good solution to the problem of variable energy ***,the purpose of this research is to model a combination of the wind-turbine system and photovoltaic cell,which is needed to investigate their ability to supply electrical *** determine this important power production,real data of solar-radiation intensity and wind are used and,in modelling photovoltaic cells,the effects of ambient temperature are also *** order to generalize the studied system in all dimensions,different scenarios have been *** to the amount of electrical power generated,during the evaluation of these scenarios,two economic parameters,namely the selected scenario of a wind/solar system with diesel-generator support,was determined.

关键词： reliability wind turbine photovoltaic cell intelligent algorithm economic analysis

Pitting Corrosion Behaviour of Monel-400 Alloy in Chloride Solutions

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Journal of Materials Science & Technology 1999年第3期15卷 208-212页

作者： V.K.Gouda i.Z.Selim A.A.Khedr and A.M.Fathi(Physical Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) Physical Chemistry Dept. National Research Centre Dokki Cairo Egypt

Pitting corrosion behaviour of Monel-400 alloy in 3.5 wt pct NaCl sodium chloride solution has been investigated using the cyclic potentiodynamic anodic polarization technique. The effect of chloride ion concentration, pH values and difFerent temperatures on the pitting parameters were determined. The morphology of the pits produced after anodic polarization treatments was inspected by scanning electron microscope (SEM). The results indicated that, the increase in chloride ion concentration shifts Epit and Eprot of the alloy toward negative values and the pitting potential is much more dependent on pH value in the basic region. The breakdown of passivity with increasing temperature may be due to kinetic changes of passivating films and dissolution rate of the alloy in its passive state

关键词： Figure Pitting Corrosion Behaviour of Monel-400 Alloy in Chloride Solutions

Regenerative Medicine: A Review of Solutions in the Treatment of Skin Defects

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Open Journal of Regenerative Medicine 2023年第2期12卷 97-113页

作者： Melika Heidarzadeh Kaveh same Fatemeh Baghaie Nia Fatemeh Khavari Sina Shahabi Mohammad Hossein Nabian saied reza Mehrpour Mohammadabadi Center for Orthopedic Trans-Disciplinary Applied Research Tehran University of Medical Sciences Tehran Iran

The issue of skin defects is a major concern of almost every trauma surgeon after surgery. Despite numerous conventional methods and introduction of the reconstruction ladder, managing skin defects is still a challenge for the trauma surgeons. in recent years, parallel to the advances in the more conventional methods of skin repair, regenerative medicine has offered new and novel treatments. This article aims to explore these contemporary regenerative solutions as well as to review the conventional methods of treating skin defects.

关键词： Regenerative Medicine Skin Wound Defect

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丝绸之路上的中国瓷器贸易与世界文明再生产

云南师范大学学报（哲学社会科学版） 2016年第4期48卷 61-78页

作者：方李莉中国艺术研究院艺术人类学研究所北京100029

本文选择"丝绸之路"上的中国瓷器贸易作为讨论主题,希望能通过概述在当年海陆丝绸之路两条道上所发生的,有关中国瓷器贸易而带来的世界文明互动的历史,让我们重新确定中国物质文化在世界文明再生产过程中所起的作用,以及所占有的位置和... 详细信息

本文选择"丝绸之路"上的中国瓷器贸易作为讨论主题,希望能通过概述在当年海陆丝绸之路两条道上所发生的,有关中国瓷器贸易而带来的世界文明互动的历史,让我们重新确定中国物质文化在世界文明再生产过程中所起的作用,以及所占有的位置和所处的坐标。古代丝绸之路上的贸易中不仅有茶叶、香料、丝绸,还有陶瓷贸易,但前者走的都是单向旅程,自东而西,最后在终点处被人消费使用而难以留下踪迹。只有瓷器,不仅历时长在,还被永远保存在博物馆和家族的传承中,由此,在文化的相互影响上发挥着长久的核心作用。另外,其所呈现的世界贸易造成了艺术图像和造型的普世性冲击,让我们看到世界不同国家艺术图像的不断相互影响及不断再生产的过程。另外,瓷器还是一种敏感度极高的人与事物之间的测压计,比其他任何商品都要来得敏感。因为它记录了来自种种面向的冲击,包括传统艺术手法、国际贸易、工业发展、政治纷扰、精英阶层思想、仪式礼俗和文化接触等。这样的讨论让我们有机会来回顾:丝绸之路上所形成的历史文化给予我们的种种启示,并能帮助我们进一步看到我们通往未来的路。

关键词：丝绸之路中国瓷器贸易世界文明再生产

2004北京“植物分子生物学与生物信息学国际学术研讨会”论文摘要

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Journal of Genetics and Genomics 2004年第9期31卷 1001-1021页

作者： Julian i.Schroeder

The Landau-level structure of a single polaron in a nanorod under a non-uniform magnetic field

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Communications in Theoretical Physics 2023年第9期75卷 168-172页

作者： Tian-Ji Ou Ran An Wei Zhang Shuang Han Yong Sun Hamid-reza Rastegar-Sedehi Xin-Jun Ma Jing-Lin Xiao institute of Condensed Matter Physics College of Physics and Electronic InformationInner Mongolia Minzu UniversityTongliao 028043China Department of Physics College of SciencesJahrom UniversityJahrom 74137-66171Iran

Nanorod is a unique low-dimensional nanometer structure in which the Landau level arrangement of polaron is essential for understanding its quasiparticle system. However, the stability of the polaron level is susceptible to external factors, such as changing magnetic *** this manuscript, the Pekar variational method is employed to calculate the external magnetic field's effect on the nanorod's polaron Landau level. it was found that different magnetic fields have different effects on the polaron energy levels of the nanorod, which demonstrated that the external environment had critical effects on the polaron energy levels. This study provides a theoretical basis for regulating the interaction between electrons and phonons in low-dimensional nanomaterials.

关键词： single polaron energy-levels non-uniform magnetic field nanorod