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Weak characteristic information extraction from early fault of wind turbine generator gearboxKeywords wind turbine generator gearbox, B-singular value decomposition, local mean decomposition, weak characteristic information extraction, early fault warning

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Frontiers of Mechanical Engineering 2017年第3期12卷 357-366页

作者： xiaoli xu Xiuli LIU Key Laboratory of Modem Measurement & Control Technology(Ministry of Education) Beijing Information Science and Technology University Beijing 100192 China

Given the weak early degradation characteristic information during early fault evolution in gearbox of wind turbine generator, traditional singular value decomposition （SVD）-based denoising may result in loss of useful information. A weak characteristic information extraction based on μ-SVD and local mean decomposition （LMD） is developed to address this problem. The basic principle of the method is as follows： Determine the denoising order based on cumulative contribution rate, perform signal reconstruction, extract and subject the noisy part of signal to LMD and μ-SVD denoising, and obtain denoised signal through superposition. Experimental results show that this method can significantly weaken signal noise, effectively extract the weak characteristic information of early fault, and facilitate the early fault warning and dynamic predictive maintenance.

关键词： wind turbine generator gearbox μ-singular value decomposition local mean decomposition weak characteristic information extraction early fault warning

Unified Variable Selection for Varying Coefficient Models with Longitudinal Data

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Journal of Systems Science & Complexity 2023年第2期36卷 822-842页

作者： xu xiaoli ZHOU Yan ZHANG Kongsheng ZHAO Mingtao School of Management Science and Engineering Anhui University of Finance and Economics College of Mathematics and Statistics Institute of Statistical SciencesShenzhen Key Laboratory of Advanced Machine Learning and ApplicationsShenzhen University Institute of Statistics and Applied Mathematics Anhui University of Finance and Economics

Variable selection for varying coefficient models includes the separation of varying and constant effects,and the selection of variables with nonzero varying effects and those with nonzero constant *** paper proposes a unified variable selection approach called the double-penalized quadratic inference functions method for varying coefficient models of longitudinal *** proposed method can not only separate varying coefficients and constant coefficients,but also estimate and select the nonzero varying coefficients and nonzero constant *** is suitable for variable selection of linear models,varying coefficient models,and partial linear varying coefficient *** regularity conditions,the proposed method is consistent in both separation and selection of varying coefficients and constant *** obtained estimators of varying coefficients possess the optimal convergence rate of non-parametric function estimation,and the estimators of nonzero constant coefficients are consistent and asymptotically ***,the authors investigate the finite sample performance of the proposed method through simulation studies and a real data *** results show that the proposed method performs better than the existing competitor.

关键词： Double-penalized quadratic inference functions longitudinal data variable selection varying coefficient models

Fault diagnosis model based on multi-manifold learning and PSO-SVM for machinery

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仪器仪表学报 2014年第S2期35卷 210-214页

作者： Wang Hongjun xu xiaoli Rosen B G Key Laboratory of Modern Measurement & Control Technology Beijing Information Science & Technology University School of Mechanic and Electric Engineering Beijing Information Science&Technology University Halmstad University

Fault diagnosis technology plays an important role in the industries due to the emergency fault of a machine could bring the heavy lost for the people and the company. A fault diagnosis model based on multi-manifold learning and particle swarm optimization support vector machine(PSO-SVM) is studied. This fault diagnosis model is used for a rolling bearing experimental of three kinds faults. The results are verified that this model based on multi-manifold learning and PSO-SVM is good at the fault sensitive features acquisition with effective accuracy.

关键词： fault diagnosis multi-manifold learning particle swarm optimization support vector machine

Subacute toxicity of exogenous manganese on rat hippocampal neurons Examination by MRI and optical microscopy

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Neural Regeneration Research 2008年第5期3卷 550-553页

作者： xiaoli xu Yun Xiang Min Yang School of Medicine ＆ Life Science Jianghan University Wuhan 430056 Hubei Province China

BACKGROUND： Manganism may cause learning and memory impairment by influencing the normal function of the hippocampus, however, this effect requires further examination. OBJECTIVE： To investigate the effects of manganism on the rat hippocampus using immunohistochemistry and MRI examination. DESIGN, TIME AND SETTING： A randomized controlled study, performed in the School of Medicine and Life Science, Jianghan University and the State Key Laboratory of Atomic ＆ Molecular Physics and Spectroscopy, Chinese Academy of Science, from July to September 2005. MATERIALS： Fourteen healthy SD rats aged two months were selected for this study. MnCl2 4H2O （BHD, UK）（batch number： 9791325）; glial fibrillary acidic protein （GFAP） staining kit （Beijing Zhongshan Biotechnology）; Biospec 4.7T/30 animal MRI formatter （Bruker, Germany）. METHODS： Fourteen rats were randomly divided into a control group （n =7） and a manganism group （n = 7）. Rats in the manganism group received intraperitoneal injection of MnCl2 · 4H2O （50 mg/kg）, once a day, for four successive days. Rats in the control group were injected according to the manganism regimen, but using saline instead of manganese solution. MAIN OUTCOME MEASURES： Twenty-four hours after the last injection, rats were examined using MRI. Immunohistochemically stained GFAP and hematoxylin-eosin stained hippocampal sections were observed under optical microscopy. RESULTS： Fourteen rats were included in the final analysis. After manganese treatment, T1 weighted image and inversion recovery MR1 demonstrated that the signal intensity was significantly enhanced in hippocampus, compared to controls. Neuronal necrosis was not observed in the hippocampus after HE staining. As compared to the control group, GFAP expression was markedly enhanced in the hippocampus of the manganism group. CONCLUSION： Within the rat brain, manganese preferentially localizes to the hippocampus and can induce astroctye activation.

关键词： manganism hippocampus rats MRI glial fibrillary acidic protein

Modulation of protein fate decision by small molecules:targeting molecular chaperone machinery

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Acta Pharmaceutica Sinica B 2020年第10期10卷 1904-1925页

作者： Lei Wang xiaoli xu Zhengyu Jiang Qidong You State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization China Pharmaceutical UniversityNanjing 210009China Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjing 210009China

Modulation of protein fate decision and protein homeostasis plays a significant role in altering the protein level,which acts as an orientation to develop drugs with new *** molecular chaperones exert significant biological functions on modulation of protein fate decision and protein homeostasis under constantly changing environmental conditions through extensive protein-protein interactions(PPIs)with their client *** the help of molecular chaperone machinery the processes of protein folding,trafficking,quality control and degradation of client proteins could be arranged *** core members of molecular chaperones,including heat shock proteins(HSPs)family and their co-chaperones,are emerging as potential drug targets since they are involved in numerous disease *** of small molecule modulators targeting not only chaperones themselves but also the PPIs among chaperones,co-chaperones and clients is attracting more and more *** modulators are widely used as chemical tools to study chaperone networks as well as potential drug candidates for a broader set of ***,we reviewed the key checkpoints of molecular chaperone machinery HSPs as well as their co-chaperones to discuss the small molecules targeting on them for modulation of protein fate decision.

关键词： Molecular chaperone Heat shock protein family Small molecule inhibitors Protein fate Protein-protein interaction

Neurochemical mechanism of the gastrointestinal interdigestive migrating motor complex in rats with acute inflammatory stomach ache

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Neural Regeneration Research 2012年第27期7卷 2136-2143页

作者： xiaoli xu Qin Li Lv Zhou Liqiang Ru Department of Anatomy School of Medicine Jianghan University Wuhan 430056 Hubei Province China Department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei ProvinceChina Department of Physiology Institute of Basic Medical Science Chinese Academy of Medical Science Beijing 100005 China

The normal gastrointestinal interdigestive migrating motor complex cycle was interrupted, and paroxysmal contraction appeared after formaldehyde-induced stomach ache. Activities of nitric oxide synthase, acetylcholinesterase and vasoactive intestinal peptide neurons were significantly reduced, whereas activities of calcitonin gene-related peptide neurons were significantly increased in the pyloric sphincter muscular layer, myenteric nerve plexus and submucous nerve plexus. Electroacupuncture at Zusanfi （ST36） suppressed paroxysmal contraction in rats with formaldehyde-induced stomach ache, and neurons in the enteric nervous system were normal. These results indicated that nitrergic neurons, cholinergic neurons, vasoactive intestinal peptide neurons and calcitonin gene-related peptide neurons in the enteric nervous system may be involved in changes to the gastrointestinal interdigestive migrating motor complex following stomach ache, and that electroacupuncture can regulate this process.

关键词： pyloric sphincter inflammatory pain interdigestive migrating motor complex enteric nervoussystem electroacupuncture neural regeneration

Research on information technology of state monitoring and fault prediction for mechatronics system

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仪器仪表学报 2016年第S1期37卷 139-145页

作者： xu xiaoli Zuo Yunbo Meng Lingxia Zhao Xiwei Liu Xiuli Beijing Information Science & Technology University Beijing Institute of Technology

The safety and reliability of mechatronics systems,particularly the high-end,large and key mechatronics equipment in service,can strongly influence on production efficiency,personnel safety,resources and *** on the demands of development of modern industries and technologies such as international industry 4.0,Made-in-China 2025 and Internet + and so on,this paper started from revealing the regularity of evolution of running state of equipment and the methods of signal processing of low signal noise ratio,proposed the key information technology of state monitoring and earlyfault-warning for equipment,put forward the typical technical line and major technical content,introduced the application of the technology to realize modern predictive maintenance of equipment and introduced the development of relevant safety monitoring *** technology will play an important role in ensuring the safety of equipment in service,preventing accidents and realizing scientific maintenance.

关键词： mechatronics system information technology state monitoring fault prediction

Early faults prediction of running state of electromechanical systems and reconfigurable integration of series safety monitoring systems

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仪器仪表学报 2014年第S2期35卷 224-232页

作者： xu xiaoli Zuo Yunbo Chen Tao Liu Xiuli Chen Shanpeng Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science and Technology University School of Mechanical and Vehicle Engineering Beijing Institute of Technology Department of Environmental Science and Engineering Faculty of Bioresources Mie University

Fault prediction technology of running state of electromechanical systems is one of the key technologies that ensure safe and reliable operation of electromechanical equipment in health state. For multiple types of modern, high-end and key electromechanical equipment, this paper will describe the early faults prediction method for multi-type electromechanical systems, which is favorable for predicting early faults of complex electromechanical systems in non-stationary, nonlinear, variable working conditions and long-time running state; the paper shall introduce the reconfigurable integration technology of series safety monitoring systems based on which the integrated development platform of series safety monitoring systems is built. This platform can adapt to integrated R&D of series safety monitoring systems characterized by high technology, multiple species and low volume. With the help of this platform, series safety monitoring systems were developed, and the Remote Network Security Monitoring Center for Facility Groups was built. Experimental research and engineering applications show that: this new fault prediction method has realized the development trend features extraction of typical electromechanical systems, multi-information fusion, intelligent information decision-making and so on, improving the processing accuracy, relevance and applicability of information; new reconfigurable integration technologies have improved the integration level and R&D efficiency of series safety monitoring systems as well as expanded the scope of application; the series safety monitoring systems developed based on reconfigurable integration platform has already played an important role in many aspects including ensuring safety operation of equipment, stabilizing product quality, optimizing running state, saving energy consumption, reducing environmental pollution, improving working conditions, carrying out scientific maintenance, advancing equipment utilization, saving mainten

关键词： electromechanical systems early faults safety control monitoring systems reconfigurable integration

Simulation study on dynamics of cylindrical gear meshing with the evolution meshing stiffness

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仪器仪表学报 2016年第S1期37卷 146-151页

作者： Ma Chao Liu Lingtao Wang Shaohong xu xiaoli Peng Yumin Beijing Information Science and Technology University

Simulation study on the cylindrical gear meshing with the evolution gear meshing stiffness is being done for better understanding the dynamic characteristics of the *** consideration of damping,bearing clearance and gear backlash nonlinearity,the dynamic model is set up and computed in *** analysis about the relationship between the kinematic responses and the meshing stiffness are carried *** the results showed that as the gear mesh stiffness is changed from small to large,the performance of the system is changed from the harmonic stable periodic motion to with one times,two times,four times,ending chaos of the stability of the *** research results would have theoretical guidance value for the fault diagnosis in engineering.

关键词： cylindrical gear meshing stiffness bifurcation