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Networked Kalman filtering with combined constraints of bandwidth and random delay

Science china(Information Sciences) 2012年第10期55卷 2343-2357页

作者： ge quanbo 1,2,wen chenglin 1 & xu tingliang 1 1 school of automation,hangzhou dianzi university,hangzhou 310018,china 2 State Key Laboratory of Industrial Control Technology,Zhejiang university,hangzhou 310027,china school of automation Hangzhou Dianzi University Hangzhou China State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou China

Kalman filter is a powerful tool in target tracking and self-localization across wireless sensor networks with many *** paper considers the filters design for networked systems with combined constraints of bandwidth and random delay,and proposes a kind of universal networked Kalman estimator for given linear time invariant(LTI) or determinate parameters(DP) systems,which are also called linear and determinate parameters(LDP) systems ***,two modeling ways to treat bit quantization error vector are given and the corresponding LDP systems taken after bit quantization are ***,we introduce an equivalent weighted summation form of the conventional linear Kalman filter,which fully uses two essential characteristics,namely offline computation property from the LDP systems and linear weighted summation property from the linear minimum mean square error ***,by adopting the replacement and innovation compensation operations,a kind of integrated networked estimator,involving two estimation algorithms with different modeling ways to bit quantization error actually,is presented based on the weighted summation filter for random delay *** proposed universal networked estimation algorithms have some outstanding advantages such as extensive application,concise algorithm structure,high estimate accuracy,and good running *** examples are demonstrated to validate the proposed networked estimation algorithms.

关键词： Kalman filter LDP systems LMMSE limited bandwidth random delay

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A new DSmT combination rule in open frame of discernment and its application

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Science china(Information Sciences) 2012年第3期55卷 551-557页

作者： wen chenglin1, xu XiaoBin1,2 , JIANG HaiNa1 & ZHOU Zhe1 1school of automation, hangzhou dianzi university, hangzhou 310018, china 2Department of automation and Tsinghua National Laboratory for Information Science and Technology, Tsinghua university, Beijing 100049, china school of automation Hangzhou DianZi University Hangzhou China Department of automation and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing China

A new combination rule based on Dezert-Smarandache theory (DSmT) is proposed to deal with the conflict evidence resulting from the non-exhaustivity of the discernment frame. A two-dimensional measure factor in Dempster-Shafer theory (DST) is extended to DSmT to judge the conflict degree between evidence. The original DSmT combination rule or new DSmT combination rule can be selected for fusion according to this degree. Finally, some examples in simultaneous fault diagnosis of motor rotor are given to illustrate the effectiveness of the proposed combination rule.

关键词： DSmT rule of combination open frame of discernment evidence conflict simultaneous faults diagnosis generalized basic probability assignment

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Some geometric properties of successive difference substitutions

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Science china(Information Sciences) 2011年第4期54卷 778-786页

作者： HOU XiaoRong 1,xu Song 1,2 & SHAO JunWei 1 1 school of automation Engineering,university of Electronic Science and Technology of china,Chengdu 611731,china 2 Faculty of Science,Ningbo university,Ningbo 315211,china school of automation Engineering University of Electronic Science and Technology of China Chengdu China Faculty of Science Ningbo University Ningbo China

This paper provides a new,geometric perspective to study successive difference substitutions,and proves that the sequence of the successive difference substitution sets is not *** interesting result that a given k-dimensional rational hyperplane can be transformed to a k-dimensional coordinate hyperplane of new variables by finite steps of successive difference substitutions is ***,a sufficient condition for the sequence of the successive difference substitution sets of a form being not terminating is *** is,a class of polynomials which cannot be proved to be positive semi-definite by the successive difference substitution method are obtained.

关键词： successive difference substitutions nonnegativity decision of forms Barycentric subdivision

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Random Delayed Kalman Fusion Based on Equivalent Conversion for the Multisensor System

Random Delayed Kalman Fusion Based on Equivalent Conversion ...

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2011 Chinese Control and Decision Conference（CCDC）

作者： Chenlin wen is with College of automation,hangzhou dianzi university,hangzhou 310018,china tingliang xu is with College of automation,hangzhou dianzi university,hangzhou 310018,china quanbo ge is with College of automation,hangzhou dianzi university,hangzhou 310018,china

Aiming at the linear time invariant or the parameters preliminary given for the multisensor target tracking system,this paper develops a random delayed Kalman filter fusion estimator based on equivalent conversion for multisensor *** algorithm effectively uses the characteristics of Kalman filter statistical parameters which can be calculated out of line,and the calculated form of measurements weighted summation under Linear Minimum Mean Square Error （LMMSE） ***,it transformed the multisensor system into the single sensor order form based on the idea of ***,it utilizes the method of one step prediction estimate and measurements prediction residual compensation to get the optimal weighting coefficient though calculating out of line and adjusting ***,it can realize the optimal update of the random delay *** last,Algorithm analysis and computer simulation indicates that this algorithm is validity and advantage.

关键词： multisensor system measurements summation random delay prediction and compensation Kalman filter.

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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

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Research on Pulsed Electron Beam Welding Gridbias Power Supply

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稀有金属材料与工程 2011年第S4期40卷 306-308页

作者： xu Guoning1,Qi Bojin1,xu Xianglong2,Dai Hailin11school of Mechanical Engineering and automation,Beihang university,Beijing 100191,china2school of Mechanical and Transportation Engineer,china university of Petroleum,Beijing 102249,china Beihang Univ Sch Mech Engn & Automat Beijing 100191 Peoples R China china Univ Petr Sch Mech & Transportat Engn Beijing 102249 Peoples R China

The pulsed electron beam welding has bigger penetration,larger depth-width ratio and better weld seams performance compared with the traditional continuous electron beam *** key technology of the pulsed electron beam welding is that how to produce pulsed beam current by the gridbias power supply,thus,a discussion and comparison on gridbias power supply that can produce pulsed beam current were made and some experiments comparison between pulsed electron beam welding and con-tinuous electron beam welding were made.

关键词： pulsed electron beam welding pulsed beam current gridbias high voltage

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Decentralized H-infinity state feedback control for discrete-time singular large-scale systems

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控制理论与应用（英文版） 2010年第2期8卷 200-204页

作者： Songlin WO 1 , Yun ZOU 2 , Shengyuan xu 2 (1.school of Electrical and Information Engineering, Jiangsu Teachers university of Technology, Changzhou Jiangsu 213001, china 2.school of automation, Nanjing university of Science and Technology, Nanjing Jiangsu 210094, china) school of Electrical and Information Engineering Jiangsu Teachers University of Technology Changzhou Jiangsu China school of automation Nanjing University of Science and Technology Nanjing Jiangsu China

The decentralized H-infinity control problem for discrete-time singular large-scale systems is considered. Based on the bounded real lemma of discrete-time singular systems, a sufficient condition for the existence of decentralized H-infinity controller for discrete-time singular large-scale systems is presented in terms of the solvability to a certain system of linear matrix inequalities by linear matrix inequality (LMI) approach, and the feasible solutions to the system of LMIs provide a parameterized representation of a set of decentralized H-infinity controller. The given example shows the application of the method.

关键词： Discrete-time singular large-scale system Linear matrix inequality (LMI) Decentralized H-infinity control

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Study on Ceramic Cutting by Plasma Arc

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厦门大学学报（自然科学版） 2002年第S1期41卷 55-56页

作者： xu wen-ji 1, FANG Jian-cheng 2, LU Yi-shen 1 (1. school of Mechanical Engineering, Dalian university of Technology, Dalian 116023, china 2. College of Mechanical Engineering and automation, Huaqiao university, Quanzhou 362011, china)

Engineering ceramics are typical difficult-to-machine materials because of high hardness and brittleness. PAC (Plasma Arc Cutting) is a very important thermal cutting process and has been successfully used in cutting stainless steel and other difficult-to-machine alloys. PAC’s application in cutting ceramics, however, is still limited because the most ceramics are not good electronic conducts, and transferred plasma arc cannot be produced between cathode and work-piece. So we presented a method of plasma arc cutting engineering ceramics with additional anode. To reduce the kerf width and to improve the kerf quality, the hydro-magnetically confined plasma arc is used to cut engineering ceramic plates. By experiments and analyses the mechanism and characteristics of hydro-magnetic confined plasma are discussed and the effects of secondary confinement on cutting quality, arc properties, and optimal process parameters are presented. When the nozzle diameter is 3 mm, the kerf width of the Al 2O 3 ceramic plate with 6 mm thickness is less than 4.6 mm, and the cutting speed reaches to 0.9～1.2 m/min. Both theoretical analysis and experimental results have proved the feasibility and validity of the newly advanced hydro-magnetic plasma arc cutting, and the following conclusion can be drawn: (1)Synthesizing the advantages of both the water-constriction and magnetic constriction, the hydro-magnetic constriction of plasma arc forms a three-dimensional constriction with improved shape and uniformity of arc column, narrower kerfs, minimal beveling of cuts and higher dross-free cutting speeds than those under either water-constriction or magnetic constriction alone.(2)Hydro-magnetic constriction is capable of improving arc stability, which is reflected in the higher arc voltage at which arc-extinction occurs, than that under any single constriction. (3)For a given diameter of nozzle, quality cut can be produced by using a lower arc current than usually required in conventional plas

关键词： plasma cutting engineering ceramic plasma confinement

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Plasma Spray Forming

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厦门大学学报（自然科学版） 2002年第S1期41卷 33-34页

作者： FANG Jian-cheng 1, xu wen-ji 2, SHI Yu-ying 1 (1.College of Mechanical Engineering and automation, HQU, Quanzhou 362011, china 2.school of Mechanical Engineering, DUT, Dalian 116023, china)

In the course of plasma spray, the plasma jet is comprehensively functioned by such effects as thermal pinch, magnetic pinch and mechanical compression and the flow is jetting at a high speed, the energy is concentrated and its center temperature is so high as to reach upwards of 15 000 ℃ which is capable of melting various kinds of materials inclusive of ceramic, it has a broad applied prospects in the fields of automobile, electronics, telecommunications, medical treatment, air navigation & space navigation and light industries etc because of being able to rapid fabricate thin-walled metals, ceramics and alloy parts thereof, metal moulds, functionally gradient material moulds and so on, and it has become a research spotlight for the scholars. The technology of plasma spray forming (PSF) is introduced, and the two different kinds of technique presented in this paper are studied. Some typical links in the course of technical process is also analyzed, including original prototype fabrication and surface treatment, post-treatment of formed workpiece and demoulding methods. When spraying, it should select the appropriate making methods of prototype according to the dimensions, shapes and forming accuracy as required by the formed parts. At the same time, it should be paid to the characteristic of the material for the prototype. The main purpose of surface treatment of the prototype is to raise the quality of formed parts and ensure the integrity demoulding of the coating. The method of the prototype’s surface treatment is closely related to the demoulding method, which is mainly comprised of destructive demoulding, non-destructive demoulding and composite demoulding, and is key technology in PSF. In order to eliminate these intrinsic defects and improve its performance, the fabricated parts can be given the necessary post-treatment so as to further raise the mechanical strength and surface quality. There are many methods for the post-treatment such as chemical reinforc

关键词： plasma spray forming forming technique

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Ultrasonic Frequency Fast-Convert Pulse Plasma Spraying Power Supply Topology

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稀有金属材料与工程 2011年第S4期40卷 297-301页

作者： Zhang Wei1,Qi Bojin1,xu Haiying21school of Mechanical Engineering and automation,BeiHang university,Beijing 100191,china2Beijing Aeronautical Manufacturing Technology Research Institute,Beijing 100024,china BeiHang Univ Sch Mech Engn & Automat Beijing 1000191 Peoples R China Beijing Aeronaut Mfg Technol Res Inst Beijing 100024 Peoples R China

Considering the high DC current and high pulse frequency characteristic of ultrasonic frequency fast-convert pulse plasma spraying process,a special power supply topology was proposed,which was composed of the mutual independent base current circuit and peak current *** current circuit was consisted of four parallel direct current power supplies,which was not only to meet the requirements of high power output,but also improved the reliability of power *** on the Boost circuit topology,a peak current circuit was designed,which could reduce effectively the output inductance influence and output ultrasonic frequency pulse high current with fast-convert rising and falling *** on the above techniques,the Ultrasonic frequency fast-convert pulse plasma spraying power supply was *** can output 5-1000A base current,0-250A peak current,and the pulse current frequency band is 20-100kHz,10%～80% duty ratio and pulse current change rate over 50A/μs.

关键词： Ultrasonic frequency pulse Fast-convert Plasma spraying

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