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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao yuan* school of Remote Sensing and Information Engineering, wuhan university, wuhan 430079, China school of Remote Sensing and Information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in China and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in China and tested at a scale of 1:32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

Fractal Analysis of Gas Diffusion Layer in PEM Fuel Cells

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Journal of wuhan university of technology(Materials Science) 2006年第1期21卷 22-25页

作者：石英肖金生 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070ChinaSchool of Automation Wuhan University of Technology Wuhan 430070 China State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070ChinaSchool of Automotive EngineeringWuhan University of Technology Wuhan 430070China

The aim of this study is to show how fractal analysis can be effectively used to characterize the texture of porous solids. The materials under study were carbon papers, the backing material of the gas diffusion layer （GDL） in Proton Exchange Membrane Fuel Cell （PEMFC）. The fractal dimensions were calculated by analyzing data from mercury porosimetry. The polytotrafluoroethylene （PTFE） treated carbon paper shows a significantly high fractal dimension value than pare sample, and the high fractal dimension signifies that the physical complexity of the pore surface is enhanced. The fractal dimension can be used as a valid parameter to monitor the textural evolution of the samples as the treatment progresses, as this behaves in a similar way to other textural parameters. The use of fractal analysis in conjunction with the results of classical characterization methods leads to a better understanding of textural modificatious in the processing of materials.

关键词： PEMFC gas diffusion layer fractal dimension mewury porosimetry

Design of Digital Control System for Cement Raw Material Preparation

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武汉理工大学学报 2006年第S3期28卷 1157-1160页

作者： ZHOU Ying LI Hongsheng school of automation,wuhan university of technology,wuhan 430070,China school of automation Wuhan University of TechnologyWuhan 430070China

This paper describes the design of cement raw material prepared digital control system by *** uses the digital technology to implement the digital control system for raw material prepared of the cement *** system improves the communication between the industrial system and locale instrument *** applies digital communication to replace ttle 4-20 mA or 24VDC signal between locale lever device and controller.

关键词： digital CIMS PROFIBUS

THEORETICAL DESIGN AND MOTION PLANNING OF NONHOLONOMIC MANIPULATOR

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 222-225页

作者： Tan Yuegang Deng Yuhui WU Zhengping school of Mechanical and Electronic Engineering,wuhan university of technology,wuhan 430070, China Department of Science and technology Studies University College London WC1E 6BT UK school of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China

A new nonholonomic transmission mechanism is proposed based on thenonholonomic theory and nonlinear control principle, and combined with conditions of thenonholonomic motion planning and control, that is researched to compose method of the motiontransfer chain from this transmission mechanism, on which a new nonholonomic manipulator isdesigned. This nonholonomic manipulator is a controllable multi-joint manipulator that actuated onlyby two-servo electromotor. Its motion expresses the characteristic of nonholonomy constraint andnonlinear, and that also satisfies the chained form convertibility. And then, using the nonlinearcontrol principle of chained system, motion characteristic of the nonholonomic manipulator isapplied. From simulation verification and analysis, the usefulness of the theoretical design andcontrol strategies is shown, and that is important in design and research of handiness robot andmulti-finger robot hand.

关键词： Nonholonomic system Nonholonomic motion planning Nonlinear controlMulti-joint Manipulator

Tele-Network Design Based on Queue Competition Algorithm

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wuhan university Journal of Natural Sciences 2003年第S1期8卷 327-330页

作者： Huang Zhang-can, Wan Li-jun, Tang Tao, Chen Zheng-xuState Key Laboratory of Software Engineering, wuhan university, wuhan 430072, Hubei, Chinaschool of Material Science and Engineering, wuhan university of technology , wuhan 430070, Hubei, Chinaschool of automation, wuhan university of technology, wuhan 430070, Hubei, Chinaschool of Science, wuhan university of technology, wuhan 430070, Hubei, China wuhan university State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university of technology School of Material Science and Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university of technology School of Automation Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university of technology School of Science Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***)

In this paper, we report research on how to design the tele-network. First of all, we defined the reliability of tele-network. According to the definition, we divide the whole reliability into two parts:the reliability of the mini-way and that of the whole system. Then we do algebra unintersection of the mini-way, deriving a function of reliability of tele-network. Also, we got a function of the cost of tele-network after analyzing the cost of arcs and points. Finally, we give a mathematical model to design a tele-network. For the algorithm, we define the distance of a network and adjacent area within certain boundaries . We present a new algorithm--Queue Competition Algorithm (QCA) based on the adjacent area . The QCA correlates sequence of fitnesses in their father-generations with hunting zone of mutation and the number of individuals generated by mutation, making the stronger fitness in a small zone converge at a local extreme value, but the weaker one takes the advantage of lots of individuals and a big zone to hunt a new local extreme value. In this way, we get the overall extreme value. Numerical simulation shows that we can get the efficient hunting and exact solution by using QCA. The QCA efficient hunting and exact solution.

关键词： reliability Queue Competition algorithm the distance of a network adjacent area

Intelligent Forecasting of Sintered Ore’s Chemical Components Based on SVM

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Journal of wuhan university of technology(Materials Science) 2011年第3期26卷 583-587页

作者：钟珞王清波 school of Computer Science and technology Wuhan University of Technology

Using object mathematical model of traditional control theory can not solve the forecasting problem of the chemical components of sintered *** order to control complicated chemical components in the manufacturing process of sintered ore,some key techniques for intelligent forecasting of the chemical components of sintered ore are studied in this paper.A new intelligent forecasting system based on SVM is proposed and *** results show that the accuracy of predictive value of every component is more than 90%.The application of our system in related companies is for more than one year and has shown satisfactory results.

关键词： sintered ore support vector machine intelligent forecasting nonlinear regression optimized control

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2, YE Sheng-ping2, YIN Wei-xin3, XUE Qiong4 (1. school of Mechanical Engineering and automation, wuhan Textile university, wuhan 430073, Hubei, China 2. State Key Laboratory of Material Processing and Die and Mould technology, Huazhong university of Science and technology, wuhan 430074, Hubei, China 3. wuhan Zhike Abrasive-Resistant Material Science and technology Development Co Ltd, wuhan 430073, Hubei, China 4. College of Science, wuhan university of technology, wuhan 430079, Hubei, China) [a] school of Mechanical Engineering and automation Wuhan Textile University Wuhan 430073 Hubei China [b] State Key Laboratory of Material Processing and Die and Mould technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] wuhan Zhike Abrasive-Resistant Material Science and technology Development Co Ltd Wuhan 430073 Hubei China [d] College of Science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2 and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

LATTICE BGK MODEL FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATION

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Journal of Hydrodynamics 2003年第3期15卷 96-102页

作者： Zhang Xiao-jun, Liu Zu-yuan school of Transportation, wuhan university of technology, wuhan 430063, China, school of Transportation Wuhan University of Technology Wuhan 430063 China

In this paper a Lattice Bhatager-Gross-Krook (LBGK) model to simulateincompressible flow is developed. The basic idea is to explicitly eliminate the compressible effect,due to the density fluctuation in the existing LBGK models. In the proposed incompressible LBGKmodel, the pressure p instead of the constant mass density ρ_0 is the independent dynamic *** incompressible Navier-Stokes equations are exactly derived from this incompressible LBGK *** order to test the LBGK model, the plane Poiseuille flow driven either by pressure gradient or afixed velocity profile at entrance as well as the 2-D Womersley flow are simulated. The numericalresults are found to be in excellent agreement with theory and the results of previous studies.

关键词： lattice BGK method incompressible navier-stokes equation poiseuilleflow wornersley flow

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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Science China(Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2 & yuan XianBao1,3 1 College of Science, China Three Gorges university, Yichang 443002, China 2 school of Physics and technology, wuhan university, wuhan 430072, China 3 Institute of Particle Physics, Central China Normal university, wuhan 430070, China 1. College of Science China Three Gorges University Yichang 443002 China 2. school of Physics and technology Wuhan University Wuhan 430072 China 3. Institute of Particle Physics Central China Normal University Wuhan 430070 China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power