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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 507-511页

作者： xinxin fu Yu Kang Pengfei Li Department of Automation University of Science and Technology of China State Key Laboratory of Fire Science Department of AutomationInstitute of Advanced TechnologyUniversity of Science and Technology of China Key Laboratory of Technology in GeoSpatial Information Processing and Application System Chinese Academy of Sciences IEEE

In this paper,we studied the approximate sampleddata observer design for a class of stochastic nonlinear ***-Maruyama approximation was investigated in this paper because it is the basis of other higher precision numerical methods,and it preserves important structures of the nonlinear ***,the form of Euler-Maruyama model is simple and easy to be *** results provide a reference for sampled-data observer design method for such stochastic nonlinear systems,and may be useful to many practical control applications,such as tracking control in mechanical *** the effectiveness of the approach is demonstrated by a simulation example.

关键词： Approximation model exponentially bounded sampled-data observer stochastic nonlinear

Control for a Class of Stochastic Mechanical Systems Based on the Discrete-Time Approximate Observer

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Journal of Systems Science & Complexity 2019年第2期32卷 526-541页

作者： fu xinxin KANG Yu LI Pengfei YU Peilong Department of Automation University of Science and Technology of China

This paper investigates the observer-based control problem of a class of stochastic mechanical systems. The system is modelled as a continuous-time It o stochastic differential equation with a discrete-time output. Euler-Maruyama approximation is used to design the discrete-time approximate observer, and an observer-based feedback controller is derived such that the closed-loop nonlinear system is exponentially stable in the mean-square sense. Also, the authors analyze the convergence of observer error when the discrete-time approximate observer servers as a state observer for the exact system. Finally, a simulation example is used to demonstrate the effectiveness of the proposed method.

关键词： Approximate model discrete-time observer exponential stability stochastic nonlinear system

Rolling Element Bearing Fault Diagnosis Using Recursive Wavelet and SOM Neural Network

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Rolling Element Bearing Fault Diagnosis Using Recursive Wave...

Research on the Evaluation System of Epoxy Asphalt Steel Deck Pavement Distress Condition

第25届中国控制与决策会议

作者： Liying Jiang xinxin fu Jianguo Cui Zhonghai Li School of Automation Shenyang Aerospace University

ISBN: (纸本)9781467355339

This paper is focused on fault diagnosis of rolling element bearing due to localized defects i.e. rolling element and outer raceway on the bearing component, which is essential to the design of high performance rotor bearing system. A new fault diagnosis method based on recursive wavelet （RW） and SOM neural network, RW-SOM neural network is proposed. First, wavelet threshold de-noising is utilized to preprocess the raw vibration signal obtained by QPZZ-Ⅱ system, which can reduce the influence from the noise and to benefit to extract the characteristic signal. Then, a new method of feature extract based on recursive wavelet is proposed in order to solve the problems of bad real-time and the long window, which are born in traditional wavelet decomposition. Finally, bearing faults are classified using SOM neural network. The simulation results show that recursive wavelet combined with SOM neural network for fault diagnosis is effective and is superior to traditional wavelet decomposition.

关键词： Recursive Wavelet SOM Neural Network Feature Extract Fault Diagnosis

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Journal of Harbin Institute of Technology(New Series) 2019年第5期26卷 41-50页

作者： Hui Zhang Yingtao Li xinxin fu Youqiang Pan College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Ncmjing 210016 China Jiangsu SinoRoad Engineering Research Institute Co. Ltd. Ncmjing 211800 China Jiangsu Highway Engineering Maintenance Co. Ltd Ncinjing210049 China

Epoxy asphalt concrete has been one of the mainstream technology of steel deck pavement in China. But little specification about evaluation system for its distress condition has been researched and maintenance was still unsystematic. The section weight coefficient of different distress is proposed by analyzing the applicability of the “Highway Performance Assessment Standards”. Indexes mainly including SDPCI PDR and PCR are presented to evaluate its distress condition. The evaluation system and maintenance plan decision tree were recommended which can assist scientific maintenance of epoxy asphalt steel deck pavement.

关键词： steel deck pavement epoxy asphalt concrete distress condition evaluation system maintenance plan

Chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27) heterojunction with fast hole extraction dynamics for continuous CO_(2) photoreduction

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Advanced Powder Materials

Advanced Powder Materials 2024年第1期3卷 13-21页

作者： Baojing Huang xinxin fu Kai Wang Liang Wang Hualei Zhang Zhongyi Liu Bin Liu Jun Li Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435000China Institute of Nanochemistry and Nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637459Singapore

Surface charge localization and inferior charge transfer efficiency seriously restrict the supply of reactive hydrogen and the reaction dynamics of CO_(2) photoreduction performance of ***,chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27)(BVO/BCS)S-scheme heterojunction with a strong internal electric field is *** and density function theory calculation results confirm that the elaborated heterojunction accelerates the vectorial migration of photogenerated charges from BiVO_(4) to Bi_(19)Cl_(3)S_(27) via the interfacial chemical bonding interactions(i.e.,Bi-O and Bi-S bonds)between Bi atoms of BVO and S atoms of BCS or Bi atoms of BCS and O atoms of BVO under light irradiation,breaking the interfacial barrier and surface charge localization of Bi_(19)Cl_(3)S_(27),and further decreasing the energy of reactive hydrogen generation,CO_(2) absorption and *** separation efficiency of photogenerated carriers is much more efficient than that counterpart individual in BVO/BCS S-scheme heterojunction *** a result,BVO/BCS heterojunction exhibits a significantly improved continuous photocatalytic performance for CO_(2) reduction and the 24 h CO yield reaches 678.27μmol⋅g^(-1).This work provides an atomic-level insight into charge transfer kinetics and CO_(2) reduction mechanism in S-scheme heterojunction.

关键词： Extraction dynamics Activated hydrogen Interfacial chemical bonds S-scheme CO_(2)photoreduction

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功率控制棒棒位标定试验堆芯过热分析

强激光与粒子束 2017年第3期29卷 56-59页

作者：王欣欣付学峰张明中广核研究院有限公司广东深圳518026

核电机组在并网前的启动物理试验,需要完成一次功率控制棒负荷曲线标定试验(RGL04试验)。试验的内容是通过快速降负荷来校核事先输入的功率棒棒位与汽轮机负荷的对应关系曲线(G9曲线)。宁德、阳江等CPR1000机组在该试验中先后出现堆芯... 详细信息

核电机组在并网前的启动物理试验,需要完成一次功率控制棒负荷曲线标定试验(RGL04试验)。试验的内容是通过快速降负荷来校核事先输入的功率棒棒位与汽轮机负荷的对应关系曲线(G9曲线)。宁德、阳江等CPR1000机组在该试验中先后出现堆芯过热较大现象,对可能导致试验过程中堆芯过热的各种因素进行了分析与评估,通过计算等温温度系数理论值来预测堆芯的过热度,并给出了过插控制棒的建议措施来降低试验中堆芯的过热度。

关键词：功率控制棒 RGL04试验 G9曲线过热

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盘扣元素在现代女装设计中的创新应用研究

丝绸 2015年第3期52卷 45-50页

作者：付馨馨陈淑聪嘉兴学院南湖学院浙江嘉兴314000

随着中国国际地位的提升,中国传统元素逐渐受到世界各国服装设计大师们的瞩目,被越来越多地运用到产品设计中去。通过研究盘扣的起源与发展、盘扣在现代女装设计中的运用现状及其传承创新,系统而深入地对盘扣制作工艺技法的创新、材质... 详细信息

随着中国国际地位的提升,中国传统元素逐渐受到世界各国服装设计大师们的瞩目,被越来越多地运用到产品设计中去。通过研究盘扣的起源与发展、盘扣在现代女装设计中的运用现状及其传承创新,系统而深入地对盘扣制作工艺技法的创新、材质的创新、外部廓形的创新、形式感的创新和整体创新上结合案例展开剖析和探讨,为中国传统元素盘扣在服装品牌中的创新应用开拓了一个新的发展方向,使得服装这一随处可见的必需品成为中国传统文化传播的载体,可以为现代女装设计提供创新方法和借鉴,从而提升本土服装品牌产品附加价值和品牌生命力。

关键词：盘扣传统元素女装中国元素工艺技法

Fault Detection of Rolling Element Bearing Based on Principal Component Analysis

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Fault Detection of Rolling Element Bearing Based on Principa...

第24届中国控制与决策会议

作者： Liying Jiang, xinxin fu, Jianguo Cui, Zhonghai Li School of Automation, Shenyang Aerospace University, Shenyang 110136, China

The Principal Component Analysis （PCA） has been widely used to detect and diagnose the faults of industry processes. However, this technique is rarely applied to the fault detection and diagnosis of rolling element bearing. The main reason is that PCA is a kind of multivariate statistical technology, but bearing vibration signal is one dimensional time series. A new method of fault detection based on PCA for rolling element bearing is proposed in this paper. Firstly, the vibration signal is mapped into a high dimensional space. Then, PCA is applied in this space. The proposed method is tested with experimental data collected from drive end ball bearing of a 2 hp Reliance Electric motor driven mechanical system. The simulation results show the PCA-based method of bearing fault detection is effective and is superior to the traditional PCA-based approach.

关键词： Vibration Signals PCA Rolling Bearing Fault Detection

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无约束全局优化问题的两种新的辅助函数法

重庆师范大学学报（自然科学版） 2014年第5期31卷 1-7页

作者：吴至友傅欣欣重庆师范大学数学学院重庆401331

填充函数法、打洞函数法和平稳点函数法是目前比较常用的求解全局优化问题的辅助函数法。本文提出两种新的辅助函数法,用于求解一般非线性规划问题的全局最优解,它不仅结合了填充函数法和打洞函数法及其平稳点函数法的特点,同时又避免... 详细信息

填充函数法、打洞函数法和平稳点函数法是目前比较常用的求解全局优化问题的辅助函数法。本文提出两种新的辅助函数法,用于求解一般非线性规划问题的全局最优解,它不仅结合了填充函数法和打洞函数法及其平稳点函数法的特点,同时又避免了它们的一些缺点(每次求解填充函数、打洞函数和平稳点函数的局部极小点以后,还需要重新求解原问题的局部极小点),而新的辅助函数的局部极小点就是原问题的局部极小点,不需要再求原问题的局部极小点。

关键词：全局优化问题局部极小点全局极小点辅助函数

基于高能粒子溅射的表面深度剖析方法现状及应用

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高电压技术 2018年第6期44卷 1946-1953页

作者：万真真付新新王永清施宁河北大学电子信息工程学院保定071002 瑞士柯帕斯服务有限公司北京代表处北京100027

近年来国内外对于材料表面问题的研究非常活跃。材料表面深度剖面分析方法不仅能像均质材料的分析方法那样获得表面元素含量的信息,而且能够用来表征从表面到基体各元素成份的纵深分布情况。为了解当前材料表面深度剖面分析技术及发展状... 详细信息

近年来国内外对于材料表面问题的研究非常活跃。材料表面深度剖面分析方法不仅能像均质材料的分析方法那样获得表面元素含量的信息,而且能够用来表征从表面到基体各元素成份的纵深分布情况。为了解当前材料表面深度剖面分析技术及发展状况,文章从各类高能粒子入射样品表面的分析机理入手,介绍了二次离子质谱法、俄歇电子能谱法、X射线光电子能谱法、辉光放电光谱法、激光诱导击穿光谱法这5种可用于深度剖析的分析方法,它们通常使用高能入射粒子轰击样品表面,将待测样品逐层原子化或离子化后,再通过光谱、质谱或电子检测装置测得元素含量的纵深分布信息。在详细阐明了这5种深度剖析方法的分析原理、分析特点、溅射坑型及其在材料表面分析中的典型应用后,分析和探讨了这几类深度剖析方法在入射粒子、适合样品、可测试元素、是否可定量分析、应用领域等方面的对比情况,明确了它们在深度剖面分析领域的各自优势和不足,指出了对几种分析技术的综合运用,有时可改进单一方法的适用性和准确度。

关键词：高能粒子深度剖面分析二次离子质谱俄歇电子能谱 X射线光电子能谱辉光放电光谱激光诱导击穿光谱等离子体