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The Analysis of the Dynamic Equilibrium State in Linear Control System

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武汉理工大学学报 2006年第S3期28卷 1059-1063页

作者： WANG Li Dept.of electrical and automation,Yangzhou University,Yangzhou 225009,china, Dept.of electrical and automation Yangzhou UniversityYangzhou 225009China

This paper discusses not a point of equilibrium to free system,but a certain family of equilibrium state of dynami- cal system with *** equilibrium state depends on the input,so it is called the dynamic equilibrium *** expression of the dynamic equilibrium state can be given under some certain *** deductions and proofs in linear control system,es- tablish the expression of the dynamic equilibrium state in two cases,where the linear systems are nonsingular or *** pre- sent the concept and the condition of the controllability of the dynamic equilibrium *** controllability of the dynamic equilib- rium state is different from the controllability of the state to system,but these two are closely related.

关键词： linear system input dynamic equilibrium state controllability

Data fusion based on fuzzy measures

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Progress in Natural Science:Materials International 2007年第8期17卷 962-970页

作者： Yue Shihong~(**) Li Yi Liu Zhengguang Wang Ping Liu Piaoyu (school of Electronic Engineering and automation,Tianjin University,Tianjin 300072,china) school of Electronic Engineering and automation Tianjin University Tianjin 300072 China

Choquet integral based on fuzzy measure is a very popular data fusion approach.A major problem in applying the Cho- quet integral is how to determine a large number of fuzzy measures as the number of attributes ***λ-fuzzy measure proposed by Sngeno is a powerful method to resolve this ***,the modeling ability of theλ-fuzzy measure is too limited to satisfy actual *** this paper,an extendedλ-fuzzy measure is proposed using Shapley value index,and the limitation of theλ-fuzzy measure is significantly overcome under little additional computational *** extended fuzzy measure has stronger modeling power than theλ- fuzzy measure,straightforwardly representing interaction among *** apply the extended fuzzy measure to an artificial data set and a real dataset in an iron-steel *** results verify the usefulness of the extended fuzzy measure compared with other main existing methods.

关键词： data fusion Cboquet integral Shapley value index fuzzy measure

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3 and Meng Dazhi2(1. National Laboratory of Pattern Recognition,Institute of automation, Chinese Academy of Sciences, Beijing 100080, china 2. College of Applied Sciences, Beijing University of Technology, Beijing 100022, china 3. school of Science, Beijing Institute of Technology, Beijing 100081, china) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China school of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Design and Develop Online Monitoring and Early-warning System of Crane Structural Stress

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武汉理工大学学报 2006年第S2期28卷 724-727页

作者： XU Huping~1 LIN Weiguo~2 XU Changsheng~2 1.school of automation,Wuhan University of Technology,Wuhan 430070,china 2.school of Material Engineering,Wuhan University of Tedmology,Wuhan 430070 ,china school of automation Wuhan University of TechnologyWuhan 430070China school of Material Engineering Wuhan University of TechnologyWuhan 430070China

This paper proposed an online monitoring and early-warning system of dynamic stress of crane metal structure, and designed this system’s hardware,including sensor unit,data gathering unit,and controlling & processing unit of this sys- tem,and discussed the waterproof protection for resistance strain wafer and scheme of data gathering and transmission of dynamic strain gauge,moreover developed system software of real-time and online monitoring dynamic stress,including data gathering by DLL and data display & processing based on Visual C++.The system applies the dynamic strain gauge to gather the data of the stress,and communicates between PLC control system of crane and upper industrial computer,so that realize the real-time online monitoring and early-warning for crane’s metal structure *** test results show this system carry on real time and online monitoring to dynamic stress of loud-bearing metal structure longly and stability,and can give an alarm and overload protection on *** the system has good practice value.

关键词： crane metal structure stress detect online monitor

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 University of Mining & Technology, Xuzhou 221008, china school of Information and electrical Engineering China University of Mining & Technology Xuzhou 221008 China

Conventional Pd/?-Al2O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent de-crease 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 ?-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：载体催化元件抗硫性能有源元件甲烷传感器纳米催化剂纳米氧化铝稳定性能工作寿命

Pattern Analysis on DC Breakdown Phenomenon of Polyethylene Films

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Transactions of Tianjin University 2006年第5期12卷 325-329页

作者：杜伯学刘勇刘弘景 school of electrical Engineering and automation Tianjin University

Pattern analysis method was used to study DC breakdown characteristics of low-density polyethylene (LDPE) film and high-density polyethylene (HDPE) film, with particular attention paid to the breakdown phenomenon identification. The breakdown pattern (BP) was recorded by a monocular-video-zoom microscope. The records showed that the effective area of BP was almost identical to the types of electrodes. The effective area was calculated by a mathematical integral method. The diameter was obtained by a mathematical statistic method. The study revealed that the DC breakdown voltage of LDPE was lower than that of HDPE. The diameter and effective area of LDPE were smaller than those of HDPE, but it is opposite for the condition of the needle-plane electrode with plane electrode grounded. As for the needle-plane electrode, the diameter and effective area with the films near the needle electrode were smaller than those near the plane electrode, and those in the middle of air gap were between them. As for the sphere-plane electrode, the diameter and effective area with the films near the plane electrode were smaller than those near the sphere electrode, and those in the middle of air gap were between them.

关键词：聚乙烯薄膜绝缘击穿图样分析 LDPE

Output feedback control of hypersonic vehicles based on neural network and high gain observer

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Science china(Information Sciences) 2011年第3期54卷 429-447页

作者： LI XinDong,XIAN Bin,DIAO Chen,YU YanPing,YANG KaiYan & ZHANG Yao The Tianjin Key Laboratory of Process Measurement and Control,school of electrical Engineering and automation,Tianjin University,Tianjin 300072,china The Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin China

In this paper,the output feedback control problem for a genetic hypersonic vehicle is considered under the restriction that only the vehicle’s velocity and altitude are measurable. High gain observers (HGO) are utilized to provide estimation signals for unmeasurable derivatives of the vehicle’s velocity and altitude. Neural network based feedforward function is designed to compensate for model uncertainties. The proposed control design require less knowledge of the hypersonic vehicle’s dynamic model. A comprehensive stability analysis of the closed loop system under the output feedback control is carried to prove that the proposed control law yields semiglobal uniformly ultimately bounded tracking while keeping all the closed loop signals bounded. Numerical simulation results are presented to validate the proposed control design.

关键词： hypersonic vehicle nonlinear output feedback control neural network high gain observer

Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science china(Technological Sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2, WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of automation, Chinese Academy of Sciences, Shenyang 110016, china 2. Graduate school, Chinese Academy of Sciences, Beijing 100039, china Correspondence should be addressed to Jing Xingjian Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China Graduate school Chinese Academy of Sciences Beijing China

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robots dynamic constraints. The direction of the coordinating force can be determined on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

STEP-NC Based High-level Machining Simulations Integrated with CAD/CAPP/CAM

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International Journal of automation and computing 2012年第5期9卷 506-517页

作者： Yu Zhang 1 Xiao-Lan Bai 1 Xun Xu 2 Yong-Xian Liu 1 1 school of Mechanical Engineering & automation,Northeastern University,Shenyang 110004,china 2 school of Engineering,University of Auckland,Auckland 1010,New Zealand school of Mechanical Engineering & automation Northeastern University Shenyang China school of Engineering University of Auckland Auckland New Zealand

With the development of manufacturing,numerical control(NC) machining simulation has become a modern tool to obtain safe and reliable machining *** some research and commercial software about NC machining simulations is available,most of them is oriented for G&M *** is a low-level data model for computer numerical control(CNC),which has inherent drawbacks such as incomplete data and lack of *** limitations hinder the development of a real simulation ***,standard for the exchange of product data-compliant numerical control(STEP-NC) is a new and high-level data model for *** provides rich information for CNC machine tools,which creates the condition for an informative and real ***,this paper proposes STEP-NC based high-level NC machining simulations solution integrated with computer-aided design/computeraided process planning/computer-aided manufacturing(CAD/CAPP/CAM).It turned out that the research provides a better informed simulation environment and promotes the development of modern manufacturing.

关键词： Standard for the exchange of product data-compliant numerical control(STEP-NC) numerical control(NC) machining machining simulation IDEF0 method ISO 6983