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3D visualization model and key techniques for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 748-752页

作者： JIN Bao-xuan1,FANG Yuan-min2.SONG Wei-wei2.1. Yunnan Provincial Geomatics Centre, Kunming 650034, china 2. Faculty of Land Resource engineering, Kunming University of {2. and technology, Kunming 650093, china [a] Yunnan Provincial Geomatics Centre Kunming 650034 China [b] Faculty of Land Resource engineering Kunming University of Science and Technology Kunming 650093 China

Digital mine is the inevitable outcome of the information processing, and is also a complicated system engineering. Firstly, for the 3D visualization application of the digital mine, the ground and underground integrative visualization framework model was proposed based on the mine entity database. So, the visualization problem was availably resolved, as well as the professional analytical ability was improved. Secondly, aiming at the irregularities, non-uniformity, dynamics of mine entities, mix modeling method based on the entity character was put forward, in which 3D expression of mine entities was realized. Lastly, the 3D visualization project for a copper mine was experimentally studied. Satisfactory results were acquired, and the rationality of visualization model and feasibility of 3D modeling were validated.

关键词： digital mine three dimension visualization framework model spatial data modeling

A new sequential learning algorithm for RBF neural networks

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science china(Technological sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. Department of Power engineering, Southeast University, Nanjing 2.0096, china 2. Department of Power engineering, Nanjing institute of technology, Nanjing 2.0013, china 1. Department of Power engineering Southeast University 210096 Nanjing China 2. Department of Power engineering Nanjing Institute of Technology 210013 Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

The Design and Properties of G.656 Optical Fiber Waveguide Design

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Journal of wuhan University of technology(Materials {2.) 2007年第1期22卷 70-73页

作者：成煜 Key Laboratory of Silicate Materials science and engineering Wuhan University of Technology Ministry of Education FiberHome Telecommunication Technologies Co. LTD WuHan 430074China

To prepare the G.656 optical fiber for the future＇s network, the methods of material design and waveguide design were applied to predict theoretic properties of the fiber. PCVD process was applied to manufacture the multi-layer GeO2. F co-doped SiO2.materials. The fiber properties were tested for the cut-off wavelength, MFD, dispersion, etc. The tested results agreed with the theoretic prediction.

关键词： G.656 Waveguide dispersion metro

Crystallization and Electrical Properties of (Ba_(0.4)Pb_(0.3))Sr_(0.3)TiO_3 Thin Film by Pulsed laser Deposition

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Journal of wuhan University of technology(Materials {2.) 2007年第4期22卷 634-637页

作者：杨卫明 Department of Electronic science and technology Huazhong University of Science and Technology

（Ba0.4Pb0.3）Sr0.3TiO3 thin films were fabricated via pulsed laser deposition （PLD） technique on Pt/TiO2.SiO2.Si substrate. The crystallization of the films was characterized by XRD and FSEM, and the experimental results suggested deposition parameters, especially the deposition temperature was the key factor in forming the perovskite structure. The dielectric properties of the film deposited with optimized parameters were studied by an Agilent 42.4A impedance analyzer at 1 MHz. The dielectric constant was 772. and the loss tangent was 0.006. In addition, the well-shaped hysteresis loop also showed that the film had a well performance in ferroelectric. The saturated polarization P, remnant polarization Pr and coercive field E were about 4.6 μC/cm2. 2.5 μC/cm2.and 2. kV/cm （the coercive voltage is 0.7 V）, respectively. It is suggested the film should be a promising candidate for microwave applications and nonvolatile ferroelectric random access memories （NvFeRAMs）.

关键词： (Ba0.4Pb0.3)Sr0.3TiO3 thin film PLD dielectric properties ferroelectric properties

The mathematical model of wetting angle of heterogeneous nucleation

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science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3 1. School of Metallurgical and Ecological engineering, University of science and {2. Beijing, Beijing 100083, china 2. School of Material science, University of science and {2. Beijing, Beijing 100083, china 3. Central Iron and Steel Research institute, Beijing 100081, china 1. School of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. School of Material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Superplasticity and Superplastic Bulging Behavior of ZrO_2.Ni Nanocomposite

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Journal of wuhan University of technology(Materials {2.) 2011年第1期26卷 56-60页

作者：丁水 Aerospace Research institute of Materials and Processing technology

ZrO2.Ni nanocomposite was produced by pulse electrodeposition and its superplastic properties were investigated by the tensile and bulging tests. The as-deposited nickel matrix has a narrow grain size distribution with a mean grain size of 45 nm. A maximum elongation of 605% was observed at 72. K and a strain rate of 1.67×10-3s-1 by tensile test. Superplastic bulging tests were subsequently performed using dies with diameters of 1 mm and 5 mm respectively based on the optimal superplastic forming temperature. The effects of forming temperature and gas pressure on bulging process were experimentally investigated. The results indicated that ZrO2.Ni nanocomposite samples can be readily bulged at 72. K with H/d value （defined as dome apex height over the die diameter） larger than 0.5, indicating that the nanocomposite has good bulging ability. SEM and TEM were used to examine the microstructure of the as-deposited and bulged samples. The observations showed that significant grain coarsening occurs during superplastic bulging, and the microstructure is found to depend on the forming temperature.

关键词： superplasticity bulging microstructure ZrO2.Ni nanocomposite

Sufficient and necessary conditions for Lyapunov stability of Lorenz system and their application

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science china(Information sciences) 2010年第8期53卷 1574-1583页

作者： LUO Qi 1 , LIAO XiaoXin 2.& ZENG ZhiGang 2.1 College of Information and Control, Nanjing University of Information science and technology, Nanjing 2.0044,{2. 2.Department of Control science and engineering, huazhong University of science and technology, Image Processing and Intelligent Control Key Laboratory of Education Ministry of{2., wuhan 43.074,{2. 1. College of Information and Control Nanjing University of Information Science and Technology Nanjing 210044 China2. Department of Control Science and Engineering Huazhong University of Science and Technology Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Wuhan 430074 China

The sufficient and necessary conditions for Lyapunov stability of the zero equilibrium point of Lorenz system are discussed, and some brief criteria are presented for globally exponential stability, globally asymptotical stability and instability. Furthermore, the behavior of the non-zero equilibrium point of Lorenz system is also investigated, and several sufficient and necessary conditions are provided for locally exponential stability and instability. The established theorems in this paper develop and extend the existing achievements on Lyapunov stability of Lorenz system. In conclusion, by applying the obtained results, some less conservative feedback-control laws are derived to guarantee the globally exponential stability of the chaos control of Chen system, Lu¨ system, Yang-Chen system and Yu-Xia Li system.

关键词： Lorenz system Lyapunov stability sufficient and necessary condition bifurcation values globally exponential synchronization

Spinning Deformation Criteria of Thin-walled Tubular Part with Longitudinal Inner Ribs

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Journal of wuhan University of technology(Materials {2.) 2006年第4期21卷 169-172页

作者：江树勇 engineering Training Center Harbin Engineering University Harbin 150001China

As a successive and local plastic deformation process, backward ball spinning was applied for the purpose of prodacing thin-walled tubular parts with longitudinal inner ribs. According to the local plastic deformation theoo,, the application of yield criterion to the spinning process and the influence of the radial spinning force component on the formability of inner ribs were analyzed. Based on yield criterion and plastic mechanics, the stable flow rule of metal material and forming criteria of the inner ribs were obtained aad conformed to the experimental results so as to contribute greatly to improving the ball spinning process and optimizing the process variables, such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank, which have a significant influenee on the formability of the inner ribs. The knowledge of the influence of the process variables such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank on the spinning process is essential to preventing the quality defects of the spun parts and obtaining the desired spun parts.

关键词： ball spinning power spinning spinning force criterion

Mechanical Properties of Layered Steel Fiber and Hybrid Fiber Reinforced Concrete

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Journal of wuhan University of technology(Materials {2.) 2008年第5期23卷 733-736页

作者：卢哲安 Hubei Key Laboratory of Roadway Bridge and Structure engineering Wuhan University of Technology

To explore a new structure form of fiber reinforced concrete, namely, the layered steel fiber and layered hybrid fiber reinforced concrete （LSFRC and LHFRC）, the mechanical properties of LSFRC and LHFRC, such as compressive strength, tensile strength, flexural strength, fatigue and durability were focused on. The experimental results show that LSFRC and LHFRC can improve the flexural strength of concrete by 2.%-50%. In the aspect of improving the flexural strength of concrete, adulterant rate has more obvious effect than length/diameter ratio. Double logarithmic fatigue equation considered liveability was founded. The impermeability of LHFRC is superior to LSFRC and plain concrete （C）. However, the porosity of LHFRC is lower than LSFRC and C. The shrinkage of LHFRC at every age is obviously lower than C. The antifreeze durability of LHFRC is also better than C.

关键词： layered steel fiber reinforced concrete mechanical properties layer hybrid fiber reinforced concrete