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Parameter identification theory of a complex model based on global optimization method

Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3 1 college of Automotive engineering, South china univer.ity of technology, Guangzhou 510640, china 2 Beijing Research Institute of Mechanical and electrical technology, Beijing 100083, china 3 Department of engineering Mechanics, Tsinghua univer.ity, Beijing 100084, china 1. college of Automotive engineering South China University of Technology Guangzhou 510640 China 2. Beijing Research Institute of Mechanical and electrical technology Beijing 100083 China 3. Department of engineering Mechanics Tsinghua University Beijing 100084 China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

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A Fast PID Type Parameter Optimal Iterative Learning Control Algorithm for Non-Positive Plants

A Fast PID Type Parameter Optimal Iterative Learning Control...

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第二十九届中国控制会议

作者： LI Hengjie,HAO Xiaohong School of electrical and information engineering,lanzhou univer.ity of technology,lanzhou,Gansu 730050,P.R.china

In order to obtain faster and more accuracy transient tracking performances for non-positive plants,a fast proportional integral difference（PID）type parameter optimal iterative learning control algorithm is *** the algorithm,the PID type operators are introduced to enhance convergence speed and a suitable set of basis functions is added to avoid the algorithm plunge into local optimal when the plant is not *** proof shows that the algorithm monotone convergence to zero no matter the system plant is positive or ***,simulations show that the algorithm also has a faster convergence speed compare with other similar algorithms.

关键词： iterative learning control Proportional integral difference Optimal

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Relations between thickness of UHMWPE’s wear debris and positive pressure of tribological system

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Chinese Science Bulletin 2008年第9期53卷 1435-1443页

作者： LIU HongTao1,2,3 & GE ShiRong1,3 1 Institute of Tribology and Reliability engineering, china univer.ity of Mining & technology, Xuzhou 221116, china 2 college of Mechanical and electrical engineering, china univer.ity of Mining & technology, Xuzhou 221116, china 3 Biotribology Center, State Key Laboratory of Tribology, Xuzhou 221116, china Institute of Tribology and Reliability engineering China University of Mining & Technology Xuzhou 221116 China college of Mechanical and electrical engineering China University of Mining & Technology Xuzhou 221116 China Biotribology Center State Key Laboratory of Tribology Xuzhou 221116 China

MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler is introduced to research the relations be- tween thickness of UHMWPE’s wear debris and positive pressure of tribological system. Research re- sults show that thickness of wear debris owns evident classification, and the first grade thickness math model and the second grade thickness math model are built. By the second grade thickness math model, the true force condition in the tribological system can be gotten, and the model can be used as a tool to modify simulating parameters of the tribological system, and it is an important inspecting method to the airtight system which cannot be examined in real time. The first grade thickness math model can describe the true working load and surface condition of work piece in the tribological sys- tem, and is an effective description method for the running condition of frictional pairs. The research results at different lubricating conditions testify the relations between thicknesses of wear debris and positive pressure of the tribological system. The fractal relation between maximal thickness of wear debris and positive pressure is discussed. The conceptions of the immutability principle and charac- teristic granularity of wear debris thickness are brought forward and discussed. In conclusion, as a stable tribological parameter owning mechanical theory basis, wear debris thickness will play an im- portant part in fault diagnosis, especially for the airtight system such as artificial joint.

关键词：摩擦学磨损面厚度分形数学模型

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基于星型配置策略的协同定位算法

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系统仿真学报 2010年第3期22卷 691-694页

作者：徐维涛郝晓弘张萍兰州理工大学电气工程与信息工程学院兰州730050

为了改善无线传感器网络整体连通性,避免监控区域出现"黑洞"现象,提出了无线传感器网络节点的星型配置策略。通过RSSI和AOA相结合的协同定位算法实现了节点定位,算法中采用影射机制建立了传感器节点的平面坐标计算新方法。计算机仿真结... 详细信息

为了改善无线传感器网络整体连通性,避免监控区域出现"黑洞"现象,提出了无线传感器网络节点的星型配置策略。通过RSSI和AOA相结合的协同定位算法实现了节点定位,算法中采用影射机制建立了传感器节点的平面坐标计算新方法。计算机仿真结果表明该算法能够明显提高节点的定位精度,定位精度小于1米。

关键词：无线传感器网络配置策略模型信道损失协同定位

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MOTION ANALYSIS AND DESIGN OF ACCUMULATOR FOR HYDRAULIC ROCK DRILL

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中国有色金属学会会刊：英文版 1996年第2期6卷 148-151页

作者： Liu Shixun(college of Mechanical and electrical engineering, Central South univer.ity of technology, Changsha 410083) CENT S UNIV TECHNOL COLL MECH & ELECT ENGNCHANGSHA 410083PEOPLES R CHINA

ＭＯＴＩＯＮＡＮＡＬＹＳＩＳＡＮＤＤＥＳＩＧＮＯＦＡＣＣＵＭＵＬＡＴＯＲＦＯＲＨＹＤＲＡＵＬＩＣＲＯＣＫＤＲＩＬＬＬｉｕＳｈｉｘｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉ... 详细信息

ＭＯＴＩＯＮＡＮＡＬＹＳＩＳＡＮＤＤＥＳＩＧＮＯＦＡＣＣＵＭＵＬＡＴＯＲＦＯＲＨＹＤＲＡＵＬＩＣＲＯＣＫＤＲＩＬＬＬｉｕＳｈｉｘｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎ...

关键词： hydraulic accumulator diaphragm service life stretching ratio parameter design,motion analvsis

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Robust Stabilization Control for a Class of Nonlinear Measure Differential Systems with Delay

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Systems Science and Systems engineering 1998年第1期8卷 18-28页

作者： YUE Dong\ XU Shifan college of information and electrical engineering china univer.ity of Mining and technology Xuzhou, Jiangsu,221008,china)

This paper considers the robust stabilization problem of a class of nonlinear measure differential systems with *** eliminate the effect of nonlinear uncertainties on the stability of a closed loop system, a nonlinear controller is *** addition, to get the stability result of closed loop dynamics, two novel lemmas are *** our approach, we do not require the assumption that the time varying delay variable γ(t) be restricted by (t)<1 , which is often required in many previous papers (e.g,see).

关键词： measure differential systems delay robust control stable

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Research and Design of IP Phone Based on VoIP technology

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微计算机信息 2003年第9期 88-89+16页

作者： Yuan,Zhanting Zhang,Qiuyu Sun,Wei(college of electrical and information engineering,Gansu Univ.of Tech.,lanzhou730050,china)

To present a VoIP-based solution to LAN/Intranet-oriented IP *** core is low power dissipation DSP chip in charge of voice codec and8/16bit single-chip in charge of communications protocol processing and control *** IP Phone can be used either as a desktop PC peripheral or as an Internet network terminal by RJ45or other *** pa-per introduces VoIP technology and H.323protocol stack,and some details of hardware design architecture are discussed yet.

关键词： IP Phone VoIP H.323protocol DSP

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Improving anti-sulfur performance of methane sensors by new vectors and active components

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Mining Science and technology 2010年第6期20卷 913-916页

作者： WANG Ying, TONG Minming, ZHANG Tao School of information and electrical engineering, china univer.ity of Mining & technology, Xuzhou 221008, china [a] School of information electrical engineering China University of Mining & Technology Xuzhou 221008 China

Conventional Pd/γ-A12O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing γ-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi- ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.

关键词： Cerium anti-sulfur stability sensitivity

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Research progress on electrical signals in higher plants

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Progress in Natural Science:Materials International 2009年第5期19卷 531-541页

作者： Xiaofei Yana, Zhongyi Wang a, Lan Huang a, Cheng Wang b, Ruifeng Hou b, Zhilong Xu b, Xiaojun Qiao b a college of information and electrical engineering, china Agricultural univer.ity, Beijing 100083, china b National engineering Research Center for information technology in Agriculture, Beijing 100097, china [a]college of information and electrical engineering China Agricultural University Beijing 100083 China [b]National Engineering Research Center for Information Technology in Agriculture Beijing 100097 China

This review introduces the characteristics of electrical signals in higher plants and their corresponding physiological significance, and describes in detail the impact of environmental factors (e.g. light and temperature) on the electrical potential of the plants. Also, we evaluate the measurement techniques used for electrical signals in plants, including intracellular measurement, extracellular measurement, measurement of the ion channel based on the patch-clamp technique and on the non-invasive microelectrode vibrating probe technique. We also give a brief review of the applications of these methods for investigating electrical signals in plants. The ionic mechanism of electrical activity in plants is then discussed in terms of environmental response in higher plants, and this is used to provide a theoretical basis for quantitative description of the electrical signals in plants. A model for interpretation of the electrical signal mechanisms in higher plants is discussed, but further experiments are required for the verification of this model.

关键词： Ion channel Temperature-induced Light-induced Ion mechanism Measurement technology

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Remote condition fault diagnosis system of Wind Turbines based on Data Mining technology

Remote condition fault diagnosis system of Wind Turbines bas...

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第三届国际自动化测试与仪器仪表学术会议

作者： Wang Huizhong Liu Guang Wang Xiaopeng (college of electrical and information engineering lanzhou Univ.of Tech 730050 china)

＜正＞A remote condition monitoring and fault diagnosis system based on data-Mining technology has been researched to ensure the large-scale Wind Turbine Generator System （WTGS） of security,stability,economy,and optimizing *** paper introduces the system’s hardware structure,software structure,and network communication. Finally,a concrete application of the system has been proved the system practicable and valid.

关键词： Wind turbine remote monitoring Fault diagnosis Data- mining

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