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Study on the Corrosion Resistance of Multiphase TRIP Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 883-887页

作者： WANG Ji-jie 1,WU Di 2.LI Zhuang 1,GUO Xiang-min 1,HE Chun-lin 3,CAI Qing-kui 3 (1.school of Materials Science and Engineering,Shenyang University of Aeronautics and Astronautics,Shenyang 110136,Liaoning,china 2.State Key Laboratory of Rolling and {2.,Northeastern University,Shenyang 110004,china 3.Liaoning Province Key Laboratory for Advanced Materials,Shenyang University,Shenyang 110044,Liaoning,china) Shenyang Univ Aeronaut & Astronaut Sch Mat Sci & Engn Shenyang 110136 Liaoning Peoples R China Northeastern Univ State Key Lab Rolling & Automat Shenyang 110004 Peoples R China Shenyang Univ Liaoning Prov Key Lab Adv Mat Shenyang 110044 Liaoning Peoples R China

Multiphase TRIP (Transformation Induced Plasticity) steels are known to combine higher strength with higher *** this paper,the corrosion resistance of this steel has been has been investigated by accelerated corrosion tests,such as wet/dry cyclic corrosion and the weight loss in *** morphologies of their rust layers were observed by using scanning electron microscopy,and the corrosion performance of these steels was discussed by analyzing the protective *** results show that the corrosion rate of steel A is significantly greater than that of steels B and C in wet/dry cyclic corrosion and weight loss *** corrosion performance of conventional C-Mn-Si TRIP steel is deteriorated in both NaHSO 3 and 3.5 wt.% NaCl aqueous *** superior corrosion performance is exhibited for TRIP steel with low alloying contents due to its high thermodynamic *** enhancement of corrosion performance of TRIP steel is attributed to the additions of alloying elements,such as Al,Cu,Cr,Mo,Ni,*** alloying elements increase the compactness of rust layers,so electrochemical characteristic of TRIP steel is improved.

关键词： TRIP steel alloying element rust layer corrosion performance

L_2.DISTURBANCE ATTENUATION FOR A CLASS OF TIME-DELAY HAMILTONIAN SYSTEMS

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Journal of Systems Science & Complexity 2011年第4期24卷 672-682页

作者： Weiwei SUN Yuzhen WANG Renming YANG Institute of automation Qufu Normal University Qufu 273165 China. school of Control Science and Engineering Shandong University Jinan 250061 China.

This paper considers the problem of L2.disturbance attenuation for a class of time-delay port-controlled Hamiltonian systems. A v-dissipative inequality is established by using a proper control law and a storage function. Then based on the Razumikhin stability theorem, a sufficient condition is proposed for the asymptotically stability of the closed-loop system. Finally, the authors investigate the case that there are time-invariant uncertainties belonging to some convex bounded polytypic domain and an L2.disturbance attenuation control law is proposed. Study of illustrative example with simulation shows that the presented method in this paper works very well in the disturbance attenuation of time-delay Hamiltonian systems.

关键词： Hamiltonian systems L2.disturbance attenuation stability time-delay.

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轮式移动机器人沙地行驶控制建模与仿真研究

系统仿真学报 2008年第18期20卷 5035-5039页

作者：谷侃锋赵明扬中国科学院沈阳自动化研究所沈阳现代装备研究设计中心

结合车轮沙土相互作用的力学分析,研究解决轮式移动机器人沙地行驶车轮过度滑转下陷问题。考虑纵列式重复通过车轮沙土力学参数的修正,建立六轮式沙地移动机器人的动力学模型,以车轮滑转率为状态变量,设计了移动机器人沙地行驶的滑模驱... 详细信息

结合车轮沙土相互作用的力学分析,研究解决轮式移动机器人沙地行驶车轮过度滑转下陷问题。考虑纵列式重复通过车轮沙土力学参数的修正,建立六轮式沙地移动机器人的动力学模型,以车轮滑转率为状态变量,设计了移动机器人沙地行驶的滑模驱动控制器跟踪车轮期望滑转率。MATLAB/Simulink仿真结果表明,采用该控制器可以较快地跟踪期望滑转率,有效地限制机器人车轮的滑转,避免车轮的过度下陷。

关键词：移动机器人车轮下陷滑转率沙地滑模控制 Simulink仿真

Receding horizon control for multi-UAVs close formation control based on differential evolution

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Science china(Information Sciences) 2010年第2期53卷 223-235页

作者： ZHANG XiangYin, DUAN HaiBin & YU YaXiang National Key Laboratory of Science and Technology on Holistic Control, school of automation Science and Electrical Engineering, Beihang University, Beijing 100191, {2. 1. National Key Laboratory of Science and Technology on Holistic Control School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China

Close formation flight is one of the most complicated problems on multi-uninhabited aerial vehicles (UAVs) coordinated control. Based on the nonlinear model of multi-UAVs close formation, a novel type of control strategy of using hybrid receding horizon control (RHC) and differential evolution algorithm is proposed. The issue of multi-UAVs close formation is transformed into several on-line optimization problems at a series of receding horizons, while the differential evolution algorithm is adopted to optimize control sequences at each receding horizon. Then, based on the Markov chain model, the convergence of differential evolution is proved. The working process of RHC controller is presented in detail, and the stability of close formation controller is also analyzed. Finally, three simulation experiments are performed, and the simulation results show the feasibility and validity of our proposed control algorithm.

关键词： uninhabited aerial vehicle (UAV) close formation receding horizon control (RHC) differential evolution (DE) Markov chain

Elevator Group-Control Policy Based on Neural Network Optimized by Genetic Algorithm

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Transactions of Tianjin University 2009年第4期15卷 245-248页

作者：沈虹万健如张志超刘英培李光叶 school of Electrical Engineering and automation Tianjin University Baoding Power Supply Company

Aiming at the diversity and nonlinearity of the elevator system control target, an effective group method based on a hybrid algorithm of genetic algorithm and neural network is presented in this paper. The genetic algorithm is used to search the weight of the neural network. At the same time, the multi-objective-based evaluation function is adopted, in which there are three main indicators including the passenger waiting time, car passengers number and the number of stops. Different weights are given to meet the actual needs. The optimal values of the evaluation function are obtained, and the optimal dispatch control of the elevator group control system based on neural network is realized. By analyzing the running of the elevator group control system, all the processes and steps are presented. The validity of the hybrid algorithm is verified by the dynamic imitation performance.

关键词： elevator group control genetic algorithm neural network hybrid algorithm

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对一类带聚类特征TSP问题的蚁群算法求解

系统仿真学报 2004年第12期16卷 2683-2686页

作者：胡小兵黄席樾重庆大学数理学院重庆400044 重庆大学自动化学院重庆400044

蚁群算法是近几年提出的一种新型的模拟进化算法,初步的研究表明该算法具有极强的鲁棒性和发现较好解的能力,但同时也存在收敛速度慢的缺点。针对带聚类特征的TSP问题,提出了一种新型的蚁群算法。该算法利用TSP问题本身所具有的聚类特征... 详细信息

蚁群算法是近几年提出的一种新型的模拟进化算法,初步的研究表明该算法具有极强的鲁棒性和发现较好解的能力,但同时也存在收敛速度慢的缺点。针对带聚类特征的TSP问题,提出了一种新型的蚁群算法。该算法利用TSP问题本身所具有的聚类特征,从数据域上将其分解成多个子问题,对每个子问题分别采用蚁群算法并行求解,最后将所有子问题的解按一定规则合并成问题的解。对带聚类特征TSP问题的仿真实验表明该算法的收敛速度得到了极大的提高。

关键词：蚁群算法聚类旅行商问题组合优化问题局部搜索

Research on Three Dimensional Computer Assistance Assembly Process Design System

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武汉理工大学学报 2006年第S3期28卷 1088-1092页

作者： HOU Wenjun YAN Yaoqi DUAN Wenjia SUN Hanxu automation school,Beijing University of Posts & Telecommunications,Beijing 100876,{2., automation school Beijing University of Posts & TelecommunicationsBeijing 100876China

The computer aided process planning will certainly play a significant role in the success of enterprise information- ization.3-dimensional design will promote Tri-dimensional process *** article analysis nowadays situation and prob- lems of assembly process planning,gives a 3-dimensional computer aided process planning system(3D-VAPP),and researches on the product information extraction,assembly sequence and path planning in visual interactive assembly process design,dynamic emulation of assembly and process verification,assembly animation outputs and automatic exploding view generation,interactive craft filling and craft knowledge management,*** also gives a multi-layer collision detect and multi-perspective automatic camera switching *** were done to ualidate the feasibility of such technology and algorithm,which established the foundation of tri-dimensional computer aided process planning.

关键词： assembly craft information extraction collision detect craft plan components position and posture

Recent progress in fingerprint recognition

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Progress in Natural Science:Materials International 2006年第3期16卷 231-240页

作者： TIAN Jie, CHEN Xinjian, ZHANG Yangyang, YANG Xin, HE Yuliang, LI Liang, XIE Weihua and ZHENG Zhipeng (Center for Biometrics and Security Research, Key Laboratory of Complex Systems and Intelligence Science, Institute of automation, Chinese Academy of Sciences, Beijing 100080, china Graduate {2. of the Chinese Academy of Sciences, Beijing 100080, china) [a]Center for Biometrics and Security Research Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Beijing China [b]Graduate school of the Chinese Academy of Sciences Beijing China

Fingerprint recognition has been increasingly used to realize personal identification in civilian' s daily life, such as ID card, fingerprints hard disk and so on. Great improvement has been achieved in the on-line fingerprint sensing technology and automatic fingerprint recognition algorithms. Various fingerprint recognition techniques, including fingerprint acquisition, classification, enhancement and matching, are highly improved. This paper overviews recent advances in fingerprint recognition and summarizes the algorithm proposed for every step with special focuses on the enhancement of low-quality fingerprints and the matching of the distorted fingerprint images. Both issues are believed to be significant and challenging tasks. In addition, we also discuss the common evaluation for the fingerprint recognition algorithm of the Fingerprint Verification Competition 2.04 (FVC2.04) and the Fingerprint Vendor Technology Evaluation 2.03 (FpVTE2.03), based on which we could measure the performance of the recognition algorithm objectively and uniformly.

关键词： biometrics fingerprint enhancement matching minutia image registration similarity measures.

Least trace extended set-membership filter

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Science china(Information Sciences) 2010年第2期53卷 258-270页

作者： HUANG Yi , CHEN ZongJi & WEI Chen National Key Laboratory of Science and Technology on Integrated Control Technology, school of automation Science and Electric Engineering, Beihang University, Beijing 100083, {2. 1. National Key Laboratory of Science and Technology on Integrated Control Technology School of Automation Science and Electric Engineering Beihang University Beijing 100083 China

To improve the consistency of estimation result, a least-trace extended set-membership filter (LTESMF) is presented for a class of nonlinear stochastic systems, which has linear output and unknown- but-bounded noise. Feedback technique is used instead of the intersection of ellipsoid-sets in the measurement update. The feedback parameter is optimized in order to minimize the trace of error bounded ellipsoid’s envelop matrix. A new stability analysis method was developed to prove the stochastic system’s stability by using the convergence of some measurement of the error bounded ellipsoid. Analysis result shows that the estimation error of LTESMF will converge to a bounded area. A simulation of SINS/GPS integrated alignment with large misalignment angles is conducted. The results demonstrate that the convergence speed and the consistency of LTESMF are much better than those of extended Kalman filter (EKF), in addition the steady estimation precision and computational complexity are close to that of EKF.

关键词： set-membership estimation nonlinear system convergence upper bound least trace stability analysis