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Impulse feature extraction method for machinery fault detection using fusion sparse coding and online dictionary learning

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Chinese Journal of Aeronautics 2015年第2期28卷 488-498页

作者： Deng Sen Jing Bo Sheng Sheng Huang Yifeng zhou hongliang Aeronautics and Astronautics Engineering College Air Force Engineering University Unit 94371 of People's Liberation Army

Impulse components in vibration signals are important fault features of complex machines. Sparse coding （SC） algorithm has been introduced as an impulse feature extraction method, but it could not guarantee a satisfactory performance in processing vibration signals with heavy background noises. In this paper, a method based on fusion sparse coding （FSC） and online dictionary learning is proposed to extract impulses efficiently. Firstly, fusion scheme of different sparse coding algorithms is presented to ensure higher reconstruction accuracy. Then, an improved online dictionary learning method using FSC scheme is established to obtain redundant dictionary and it can capture specific features of training samples and reconstruct the sparse approximation of vibration signals. Simulation shows that this method has a good performance in solving sparse coefficients and training redundant dictionary compared with other methods. Lastly, the proposed method is further applied to processing aircraft engine rotor vibration signals. Compared with other feature extraction approaches, our method can extract impulse features accurately and efficiently from heavy noisy vibration signal, which has significant supports for machinery fault detection and diagnosis.

关键词： Dictionary learning Fault detection Impulse feature extraction Information fusion Sparse coding

Feasibility study of miniature near-infrared spectrometer for the measurement of solar irradiance within Arctic snow-cover sea ice

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Acta Oceanologica Sinica 2020年第9期39卷 115-124页

作者： Liwen Nan Xiaoping Wang Hangzhou Wang hongliang zhou Ying Chen Ocean College Zhejiang UniversityZhoushan 316021China Zhejiang Heli Electrical Engineering Co. Ltd.Taizhou 317000China

The extremely low temperature,high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea *** feasibility of using a miniature low-power near-infrared spectrometer module to measure solar radiation in Arctic sea ice environments was investigated in this *** and integration time dependences of the spectrometer module were examined over the entire target operating range of–50°C to 30°C,well below the specified operating range of this *** these observations,a dark output prediction model was developed to represent dark output as a function of temperature and integration ***-induced biases in the saturation output and linear operating range of the spectrometer were also *** and integration time dependences of the signal output were *** signal output correction models were developed and compared,to convert the signal output at any temperature within the operating temperature range and integration time to that measured at the reference temperature and integration *** overall performance of the spectrometer was evaluated by integrating it into a refined fiber optic spectrometry system and measuring solar irradiance distribution in the ice cover with thickness of 1.85 m in the Arctic during the 9th Chinese National Arctic Research *** general shape of the measured solar irradiance above the snow surface agreed well with that measured by other commercial oceanographic *** measured optical properties of the sea ice were generally comparable to those of similar ice measured using other *** approach provides a general framework for assessing the feasibility of using spectrometers for applications in cold environments.

关键词： near-infrared spectrometer low-temperature Arctic sea ice

Effect of Stress and Galvanic Factors on the Corrosion Behave of Aluminum Alloy

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Journal of Wuhan University of Technology(Materials Science) 2018年第3期33卷 688-696页

作者：崔腾飞刘道新 SHI Ping'an LIU Jianjun YI Yihui zhou hongliang Institute of Corrosion and Protection Northwestern Polytechnical University Xi'an 710072 China China Academy of Engineering Physics Mianyang 621900 China

The interaction between stress and galvanic during the corrosion process of 5050 aluminum alloys was studied and the evolution of mechanics properties was indicated. Electrochemical impedance technique and scanning electron microscopy were used to analyze the surface electrochemical states and the corrosion morphology. At the same time, corrosion kinetics and thermodynamic theory were used to analyze the influencing mechanism of the stress factor and the galvanic factor. The results show that both of galvanic factor and tensile stress factor can increase the corrosion potential of aluminum alloys and result in the corrosion resistance decrease. With decreasing corrosion resistance, the mechanical properties of aluminum alloys decrease. These phenomena are attributed to two reasons： One is that aluminum alloys may under the condition of anodic polarization after coupled with 40 Cr Ni Mo A steel, so the corrosion can be promoted; The other is that with increasing stress, the electrochemical potential of 5050 aluminum alloys decreases and the potential difference between two materials increases, so the corrosion becomes serious. Compared to the stress factor, the galvanic factor is significant.

关键词： aluminum alloy stress galvanic mechanical-electrochemistry electrochemical impedances spectroscopy

Road Friction Coefficient Estimation Based on BP Neural Network 36

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Road Friction Coefficient Estimation Based on BP Neural Netw...

Development and application of the new BPM system data processing program at Hefei light source

第36届中国控制会议

作者： Tao Song hongliang zhou Haifeng Liu Automotive Electronics Engineering Center Harbin Institute of Technology Foundation and Interdisciplinary Science Research Institute Harbin Institute of Technology

ISBN: (纸本)9781538629185

In the development process of automotive chassis control system,it is difficult to estimate road parameters *** on vehicle force analysis and Dugoff tire model,the method of road friction coefficient estimation using BP neural network is proposed based on the motion states in the vehicle running ***,the simulation of road friction coefficient estimation method is carried out a high precision vehicle dynamics simulation software *** results show that the algorithm can estimate road friction coefficient well.

关键词： Road friction coefficient neural network vehicle dynamic simulation

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Nuclear Science and Techniques 2012年第5期23卷 261-266页

作者： MA Tianji YANG Yongliang SUN Baogen ZOU Junying LU Ping zhou Zeran XU hongliang NSRL School of Nuclear Science and Technology University of Science and Technology of China Hefei 230029 China

A data processing program has been applied for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system in the upgrade project will be equipped with Libera Brilliance BPM processors to replace the old Bergoz MX-BPM processors. The embedded Linux system on Libera has completed some important work, including instrument status check,data acquisition, position calculation, EPICS IOC data release,and so on. A new EPICS record type has been developed to recalculate the beam position with log-ratio method. The property of the new position data was analyzed in the time and frequency domain. The results show that the rms value of beam position measurement resolution can be up to submicron. Preliminary studies have been carried out on the measurement of the tune and the beam lifetime with this new BPM system.

关键词：数据处理程序 PM系统合肥光源嵌入式Linux系统 EPICS 应用开发位置数据

Flow behavior of UCM viscoelastic fluid in sudden contraction channel

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Natural Science 2010年第7期2卷 780-785页

作者： Chunquan Fu hongliang zhou Hongjun Yin Huiying Zhong Haimei Jiang 不详

A finite volume method for the numerical solution of viscoelastic flows is given. The flow of a differential upper-convected Maxwell (UCM) fluid through a contraction channel has been chosen as a prototype example. The conservation and constitutive equations are solved using the finite volume method (FVM) in a staggered grid with an upwind scheme for the viscoelastic stresses and a hybrid scheme for the velocities. An enhanced-in-speed pressure-correction algorithm is used and a method for handling the source term in the momentum equations is employed. Improved accuracy is achieved by a special discretization of the boundary conditions. Stable solutions are obtained for higher Weissenberg number (We), further extending the range of simulations with the FVM. Numerical results show the viscoelasticity of polymer solutions is the main factor influencing the sweep efficiency.

关键词： Upper-Convected Maxwell (UCM) Model Finite Volume Method Viscoelasticity Sweep Efficiency

Design and evaluation of path following controller based on MPC for autonomous vehicle

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Design and evaluation of path following controller based on ...

太阳的后裔:论西班牙戏剧《哥伦布发现新世界》的印第安人及其婚庆仪式

第36届中国控制会议

作者： hongliang zhou Levent Güven? Zhiyuan Liu Automotive Electronic Engineering Center Harbin Institute of Technology Center of Automotive Research(CAR) Ohio State University

This paper proposes a model predictive control（MPC） for autonomous vehicle path following *** solve the control problem,a nonlinear path following model is used,which includes 2 degree-of-freedom single track vehicle dynamics model and path following error *** control problem is to control vehicle to run on the reference path with the heading angle along the road orientation ***,a controller based on MPC method is designed,and a C-based algorithm is implemented to solve the nonlinear optimization problem in *** proposed control system is tested in a hardware-in-theloop simulation platform and the robustness is tested by adding noise to lateral vehicle speed and modifying model *** is testified that the control performance is satisfied in different situations.

关键词： Autonomous vehicle path following model predictive control hardware-in-the-loop simulation

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戏剧（中央戏剧学院学报） 2022年第3期203卷 126-136页

作者：周宏亮浙江大学传媒与国际文化学院

本文以西班牙黄金世纪戏剧家洛佩·德·维加的代表作、“美洲三部曲”的第一部《哥伦布发现新世界》为研究对象,分析大航海时代的西班牙对于美洲的侵略与殖民,探讨美洲原住民对于以哥伦布为代表的西班牙“探索者”们的献媚与投诚。此外... 详细信息

本文以西班牙黄金世纪戏剧家洛佩·德·维加的代表作、“美洲三部曲”的第一部《哥伦布发现新世界》为研究对象,分析大航海时代的西班牙对于美洲的侵略与殖民,探讨美洲原住民对于以哥伦布为代表的西班牙“探索者”们的献媚与投诚。此外,本文还归纳了本剧中重点展示的巴哈马群岛印第安人的婚庆仪式,总结出其所具有的三大特点,即暴力抢婚、太阳颂歌和神前婚誓。

关键词：西班牙古典戏剧洛佩·德·维加印第安人戏剧与仪式

A Novel Two-Section Co-Cavity Wavelength Tunable Sem iconductor Laser

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Journal of Semiconductors 1999年第9期 816-822页

作者： Zhao Yanrui, Wang Wei, Wang Xiaojie, Zhu hongliang, zhou Fan, Ma Chaohua(National Research Center for Optoelectronic Technology,Institute of Semiconductors, The Chinese Academy of Sciences, Beijing\ 100083)

A novel wavelength tunable semiconductor laser based on DFB (Distributed Feedback) structure with two non\|uniform sections and co\|cavity is reported in this *** laser structure was grown by three\|step MOCVD and subsequently processed into the PBH\|LD (Planar Buried Heterostructure\|Laser Diode) *** device was tuned in two ways.A discontinuous wavelength tuning range of 11 1nm and a continuous wavelength tuning range of 2 6nm was achieved in different tuning *** one control current was used to have the wavelength tuned in both ways.

关键词： Wang Co A Novel Two-Section Co-Cavity Wavelength Tunable Sem iconductor Laser