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Data-driven Subspace Identification and Predictive control for a NIAT Process Platform

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Data-driven Subspace Identification and Predictive Control f...

第24届中国控制与决策会议

作者： Lu Wang, Ning Li, Shaoyuan Li department of Automation, Shanghai Jiao Tong university, key laboratory of System control and Information processing, ministry of education of china, Shanghai 200240

In this paper, a data-driven subspace identification method and a model predictive controller are presented for a NIAT platform. First, a data-driven subspace identification method for the process modeling is used. Based on the model, we design a predictive controller. Then considering SISO/ TITO cases of the platform respectively. Both the modeling and control effectiveness of the proposed methods are validated by the experiments’ results.

关键词： Data-driven subspace identification model predictive control NIAT platform

Connected Flocking of Multi-Agent System Based on Distributed Eigenvalue Estimation

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Connected Flocking of Multi-Agent System Based on Distribute...

第三十届中国控制会议

作者： LI Xiaoli~1,ZHANG Shanwei~2,XI Yugeng~2 1.School of Information science and technology,Donghua university,Shanghai 201620,P.R.china 2.department of Automation,Shanghai Jiao Tong university, and key laboratory of System control and Information processing,ministry of education of china,Shanghai 200240,P.R.china

＜正＞As a global property,connectivity of group plays a critical role in cooperative flocking and its stability foundation of multi-agent *** this paper,the algebraic value of group connectivity,*** second smallest eigenvalue of group Laplacian,as well as the corresponding eigenvector is estimated in a completely distributed style. Based on the estimated parameters,a distributed cooperative algorithm is developed both to steer the agents to the desired flocking motion and to induce the second smallest eigenvalue of Laplacian to be positive,which implies the connectivity of controlled groupⅠs preserved during *** from the common potential/tension function method which keeps some certain edges all the time,the algorithm proposed in this paper guarantees the connectivity while permitting any existing edge to be broken,which thus forces more relaxed constraints to the motions of agents for the connectivity preservation compared with the former.

关键词： Connectivity Flocking Distributed Eigenvalue Estimation Multi-agent System

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熔融共混法制备EBA／LDH纳米复合材料

武汉理工大学学报 2009年第8期31卷 25-28页

作者：黄年华李治华刘肖王维王建祺新型纺织材料绿色加工及其功能化教育部重点实验室武汉科技学院武汉430073 武汉科技学院高分子科学与工程系武汉430073 北京理工大学阻燃材料国家专业实验室北京100081

通过熔融共混法制备出剥离型乙烯-丙烯酸丁酯共聚物(EBA)/MgAl层状双氢氧化物(LDH)纳米复合材料。采用XRD、透射电镜(TEM)和热重分析(TGA)等技术对纳米复合材料的结构、形貌、热性能及力学性能进行了研究。XRD、FTIR和TEM结果表明,十二... 详细信息

通过熔融共混法制备出剥离型乙烯-丙烯酸丁酯共聚物(EBA)/MgAl层状双氢氧化物(LDH)纳米复合材料。采用XRD、透射电镜(TEM)和热重分析(TGA)等技术对纳米复合材料的结构、形貌、热性能及力学性能进行了研究。XRD、FTIR和TEM结果表明,十二烷基单磷酸根离子(PK)嵌入了LDH层间,使LDH的层间距显著增大;在强剪切力作用下,有机化的LDH可在熔融的EBA基体中剥离成纳米片层,均匀地分散在EBA的基体中。随着LDH含量的增加,纳米复合材料的拉伸强度和断裂伸长率先增后降,在LDH的含量为3%和2%时分别达到最大值。当LDH的质量百分含量为2%时,纳米复合材料的热起始分解温度(T10%)相比于纯EBA提高29℃,LDH能够促进EBA成炭。

关键词：乙烯-丙烯酸丁酯共聚物层状双氢氧化物纳米复合材料熔融共混

Robust cooperative spectrum sensing schemes for fading channels in cognitive radio networks

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science china(Information sciences) 2011年第2期54卷 348-359页

作者： YUE WenJing1,2, ZHENG BaoYu1,2, MENG QingMin1, CUI JingWu1 & XIE PeiZhong1 1Institute of Signal processing and Transmission, Nanjing university of Posts and Telecommunications, Nanjing 210003, china 2department of Electronic engineering, Shanghai Jiaotong university, Shanghai 200240, china 1. Institute of Signal processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China2. Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

In cognitive radio systems, cooperative spectrum sensing can detect the presence of the primary user accurately. In practice, however, since the sensing observations are forwarded to a data collector through fading channels, the sensing performance is severely degraded. To deal with this problem, in this paper, we first propose a secondary user selection based cooperative spectrum sensing method to improve sensing performance by decreasing the reporting errors introduced by the fading channels. More specifically, only the secondary users with better signal-to-noise ratio (SNR) for reporting channels are allowed to send their local binary decisions (0 or 1) to the data collector while the others will send nothing. Additionally, we further propose a diversity based cooperative spectrum sensing method which applies existing space-time coding. By exploiting space diversity in CR network, the reporting errors introduced by the fading channel can be decreased and then the sensing performance is improved significantly. For either proposed cooperative spectrum sensing method, the sensing performance is derived and the analytical performance results are given. Our analysis and numerical results verify that proposed methods outperform the conventional cooperative spectrum sensing with OR-rule by taking into account the error effect on the reporting channels.

关键词： cognitive radio (CR) spectrum sensing energy detection diversity technique space-time coding

Effect of Transference Velocity on Structure of Porous Metals Fabricated by Continuous Casting Gasar Process

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Effect of Transference Velocity on Structure of Porous Metal...

第69届世界铸造会议暨2010中国铸造活动周

作者： ~* Liu Yuan Zhang Xingming Li Yanxiang key laboratory for Advanced Materials processing technology(ministry of education), department of Mechanical engineering,Tsinghua university,Beijing 100084,china

Transference velocity is an important processing parameter to influence the final lotus-type porous structure fabricated by continuous casting Gasar *** solving the solute diffusion equation,a theoretical model was developed to predict the effect of the transference velocity on the porosity,the pore diameter and the inter-pore *** predicted values at different transference velocities have a good agreement with the corresponding experimental results obtained by Japanese *** average pore diameter and the inter-pore spacing L both have a prominent decrease with the increase of transference velocity v,but the porosity only has a slight *** theoretical relationships between the pore radius r,the inter-pore spacing and the transference velocity can be described by the two simple equations as r ·v = A and L·v= B,whereA and B are all constants depending on the used gas pressures and the melt temperature.

关键词： porous metal metal-gas eutectic continuous casting transference velocity

Study of Synthesis Identification in Cutting Process with Fuzzy Neural Network

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厦门大学学报（自然科学版） 2002年第S1期41卷 40-41页

作者： LIN Bin, YU Si-yuan, ZHU Hong-tao, ZHU Meng-zhou, LIN Meng-xia (The State education ministry key laboratory of High Temperature Structure Ceramics and Machining technology of engineering Ceramics, Tianjin university, Tianjin 300072, china)

With the development of industrial production modernization, FMS and CIMS will become more and more popularized. For its control system is increasingly modeled, intellectualized and automatized, in order to raise the reliability and stability in the manufacturing process, the comprehensive monitoring and diagnosis aimed at cutting tool wear and chatter become more and more important and get rapid development. The paper tried to discuss of the intellectual status identification method based on acoustics-vibra characteristics of machining process, and propose that the working conditions may be taken as a core, complex fuzzy inference neural network model based on artificial neural network theory, and by using various kinds of modernized signal processing method to abstract enough characteristics parameters which will reflect overall processing status from machining acoustics-vibra signal as information source, to identify different working condition, and provide guarantee for automation and intelligence in machining process. The complex network is composed of NNw and NNs, Each of them is composed of BP model network, NNw is weight network at rule condition, NNs is decision-making network of each status. Y out is final inference result which is to take subordinate degree as weight from NNw, to weight reflecting result from NNs and obtain status inference of monitoring system. In the process of machining, the acoustics-vibor signal were gotten by the acoustimeter and the acceleration piezoelectricity detector, the date is analysed by the signal processing software in time and frequency domain, then form multi feature parameter vector of criterion pattern samples for the different stage of cutting chatter and acoustics-vibra multi feature parameter vector. The vector can give a accurate and comprehensive description for the cutting process, and have the characteristic which are speediness of time domain and veracity of frequency domain. The research works have been pract

关键词： artificial neural network, synthesis identification, fuzzy inference on-line monitoring, acoustics-vibra signal

一个基于对象的图像检索系统:Basestar

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计算机工程与应用 2003年第23期39卷 45-48,101页

作者：王昱丁明跃周成平龙欣胡莹图像处理与智能控制国家教育部重点实验室华中科技大学图像识别与人工智能研究所武汉430074

图像检索是近年为适应国际互连网以及图像数据库高速发展而出现的一门新技术。该文建立了一个基于对象的图像检索系统-Basestar。该系统针对传统图像检索方法偏重图像整体特征,忽略用户对图像感知等缺点,采用用户参与方式,自动准确分割... 详细信息

图像检索是近年为适应国际互连网以及图像数据库高速发展而出现的一门新技术。该文建立了一个基于对象的图像检索系统-Basestar。该系统针对传统图像检索方法偏重图像整体特征,忽略用户对图像感知等缺点,采用用户参与方式,自动准确分割对象,并在此基础上利用对象颜色和形状特征对图像实现检索。实验结果表明该系统取得了良好的检索效果。

关键词：图像检索图像分割不变性感知系统

Low Cycle Fatigue Life prediction of a 300MW Steam Turbine Rotor using a New nonlinear Accumulation Approach

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Low Cycle Fatigue Life prediction of a 300MW Steam Turbine R...

第24届中国控制与决策会议

作者： Yong-jian Sun Li-sheng Hu * department of Automation, Shanghai Jiao Tong university, and key laboratory of System control And Information processing, ministry of education of china, Shanghai 200240, PR china

A new nonlinear model is proposed to assess the low cycle fatigue life of a steam turbine rotor . Temperature field and stress field of a 300MW steam turbine under normal sliding parameters stop is computed using Finite element analysis. For the reason considering the cyclic stress-strain relation , the new model shows a conservative character . The result is compared with that from the linear accumulation theory . The comparison shows that this new nonlinear model describes the damage accumulation more precisely and reasonably in engineering .

关键词： low cycle fatigue continuum damage mechanics steam turbine rotor finite element analysis

Crystallization behavior of Ni_(54)Mn_(25.1)Ga_(20.9) ferromagnetic shape memory thin film

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Rare Metals 2007年第S1期26卷 139-142页

作者： MARTIN Saunders Centre for Microscopy and Microanalysis University of Western AustraliaNedlandsW.A.6009Australia

NiMnGaferromagnetic shape memory thin film was deposited onto Al foil using *** sputtering *** crystallization behavior of the film was investigated by XRD and *** activation energy of crystallization of the film was calculated by Kissinger’s *** results show that the crystallization temperature of NiMnGafree-standing thin film in martensite state is 372 ℃,and the activation energy of crystallization is about 191.9 kJ·mol-1.

关键词： Ni-Mn-Ga ferromagnetic shape memory alloys thin films crystallization