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Fast-moving target tracking based on mean shift and frame-difference methods

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Journal of Systems Engineering and Electronics 2011年第4期22卷 587-592页

作者： Hongpeng Yin Yi Chai Simon x. yang xiaoyan yang College of Automation Chongqing University Chongqing 400044 E R. China State Key Laboratory of Power Transmission Equipment & System Security and New Technology College of Automation Chongqing University Chongqing 400044 P. R. China School of Engineering University of Guelph Guelph N1G 2W1 Canada

The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrating the mean shift algorithm and frame-difference methods. The rough position of the moving tar- get is first located by the direct frame-difference algorithm and three-frame-difference algorithm for the immobile camera scenes and mobile camera scenes, respectively. Then, the mean shift algorithm is used to achieve precise tracking of the target. Several tracking experiments show that the proposed method can effectively track first moving targets and overcome the tracking error accumulation problem.

关键词： mean shift frame-difference method target tracking,computer vision.

Approximate Augmented Lagrangian Functions and Nonlinear Semidefinite Programs

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1283-1296页

作者： x.x.HUANG K.L.TEO x.Q.yang School of Management Fudan University Shanghai 200433 P. R. China and Department of Mathematics and Computer Science Chongqing Normal UniversityChongqing 400047 P. R. China Department of Mathematics and Statistics Curtin University of Technology Perth Australia Department of Applied Mathematics The Hong Kong Polytechnic UniversityKowloon Hong Kong P. R. China

In this paper, an approximate augmented Lagrangian function for nonlinear semidefinite programs is introduced. Some basic properties of the approximate augmented Lagrange function such as monotonicity and convexity are discussed. Necessary and sufficient conditions for approximate strong duality results are derived. Conditions for an approximate exact penalty representation in the framework of augmented Lagrangian are given. Under certain conditions, it is shown that any limit point of a sequence of stationary points of approximate augmented Lagrangian problems is a KKT point of the original semidefinite program and that a sequence of optimal solutions to augmented Lagrangian problems converges to a solution of the original semidefinite program.

关键词： semidefinite programming augmented Lagrangian duality exact penalty convergence,stationary point

Designation of a binocular structure for complex sources of x-rays and neutron source

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Radiation Detection Technology and Methods 2020年第2期4卷 190-195页

作者： x.B.yang x.B.Qin P.H.Liu T.Li K.Zhuang Beijing Engineering Research Center of Radiographic Techniques and Equipment Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China x-Lab The Second Academy of China Aerospace Science and Industry Corporation LimitedBeijingChina

Purpose A structure,used as a complex source of x-rays and neutron source,is designed with the assistance of CST module *** Particles of H-and electron,attracted from a plasma source,are designed to be separated by an energy *** after the separation,the trajectory and beam quality of H-are controlled by a special designation of potential barrier and potential *** both particles are then accelerated by three pairs of pierce similar pole to an energy of 150 keV to produce x-rays/*** With proper optimization of structure and potential combination,a binocular structure with beam center distance of 15 mm,beam diameter smaller than 3.5 mm has been devised,which gives a feasible suggestion to produce two rays with one structure in the same time.

关键词： Complex source Orthogonal field Potential barrier Pierce pole Plasma

Eutectic-reaction brazing of Al_(0.3)CoCrFeNi high-entropy alloys using Ni/Nb/Ni interlayers

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Journal of Materials Science & Technology 2022年第26期121卷 245-255页

作者： Y.Lei J.Sun x.G.Song M.x.yang T.L.yang J.Yin State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Beijing Power Machinery Institute Beijing 100074China Sichuan Aerospace Changzheng Equipment Manufacturing Co. Ltd.Chengdu 610100China

In this study,a novel eutectic-reaction brazing of Al_(0.3)CoCrFeNi high-entropy alloys(HEAs)^(1)was investigated with a design of laminated Ni/Nb/Ni *** typical Al_(0.3)CoCrFeNi brazing seam consisted of proeutecticγ,the lamellar eutectic structure composed of face-centered cubic(FCC)phase(eutecticγ)and C14 Laves,as well as a few amounts of Nb based solid solution.A high density of nanoscale ordered L1_(2)(γ)phase was precipitated withinγphase *** the brazing temperature raised from 1200 to 1320℃,the dissolution volume of Al_(0.3)CoCrFeNi alloy into Ni-Nb liquid was *** microstructure of the brazing seam changed from hypereutectic(blocky Laves+γphase)to eutectic(Laves+eutecticγ)to hypoeutectic structures(proeutecticγ+Laves/γeutectic structure).The shear strength of joints was increased gradually due to the formation of eutectic lamellae and the cellular growth of proeutecticγ*** maximum shear strength of the joint brazed at 1320℃for 10 min was up to 592 MPa,reaching 95%of the base *** joint mainly ruptured in the soft proeutecticγphase in a ductile fracture mode.

关键词： High-entropy alloys Brazing Eutectic structure Shear strength

Curvature-induced noncommutativity of two different components of momentum for a particle on a hypersurface

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Communications in Theoretical Physics 2021年第2期73卷 73-77页

作者： Z Li x yang Q H Liu School for Theoretical Physics School of Physics and ElectronicsHunan UniversiyChangsha 410082China School of Materials Science and Engineering Guilin University of Electronic TechnologyGuilin541004China Synergetice Innovation Center for Quantum Efects and Applications(SICQEA) Hunan Normal UniversityChangsha 410081China

As a nonrelativistic particle constrained to remain on an(N−1)-dimensional((N≥2))hypersurface embedded in an N-dimensional Euclidean space,two different components pi and pj(i,j=1,2,3,...N)of the Cartesian momentum of the particle are not mutually commutative,and explicitly commutation relations[p^(^)_(i),p^(^)_(j)](≠0) depend on products of positions and momenta in uncontrollable *** generalized Dupin indicatrix of the hypersurface,a local analysis technique,is utilized to explore the dependence of the noncommutativity on the curvatures around a local point of the *** first finding is that the noncommutativity can be grouped into two categories;one is the product of a sectional curvature and the angular momentum,and another is the product of a principal curvature and the *** second finding is that,for a small circle lying a tangential plane covering the local point,the noncommutativity leads to a rotation operator and the amount of the rotation is an angle anholonomy;and along each of the normal sectional curves centering the given point the noncommutativity leads to a translation plus an additional rotation and the amount of the rotation is one half of the tangential angle change of the arc.

关键词： constrained motion quantization hypersurface Dirac brackets geometric momentum

Multi-AUV SOM task allocation algorithm considering initial orientation and ocean current environment

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Frontiers of Information Technology & Electronic Engineering 2019年第3期20卷 330-341页

作者： Da-qi ZHU Yun QU Simon x.yang Laboratory of Underwater Vehicles and Intelligent Systems Shanghai Maritime University Advanced Robotics and Intelligent Systems Laboratory University of Guelph

There is an ocean current in the actual underwater working environment. An improved self-organizing neural network task allocation model of multiple autonomous underwater vehicles(AUVs) is proposed for a three-dimensional underwater workspace in the ocean current. Each AUV in the model will be competed, and the shortest path under an ocean current and different azimuths will be selected for task assignment and path planning while guaranteeing the least total consumption. First, the initial position and orientation of each AUV are determined. The velocity and azimuths of the constant ocean current are determined. Then the AUV task assignment problem in the constant ocean current environment is considered. The AUV that has the shortest path is selected for task assignment and path planning. Finally, to prove the effectiveness of the proposed method, simulation results are given.

关键词： Autonomous underwater vehicles Self-organizing neural networks Azimuths Ocean current

Development and Electrochemical Studies of Ruthenium Based Mixed Oxide Catalyst Electrodes for Chlorine Evolution

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Chemical Research in Chinese Universities 2002年第2期18卷 133-138页

作者： L.x.yang J.P.G.Farr Department of Chemical and Processing Engineering University of Newcastle Merz CourtNewcastle upon Tyne NE17RU School of Metallurgy and Materials The University of Birmingham EdgbastonBirmingham B152TTUK

Experimental results are presented which allow comparison of the electrochemical performance of RuO 2/Ti, Ru 0 3 Sn 0 7 O 2/Ti and Ru 0 3 V 0 7 O 2/Ti catalysts prepared on a titanium substrate by thermal decomposition from respective precursors. The highest activity for chlorine evolution is observed on the Ru 0 3 V 0 7 O 2/Ti electrode, lower on Ru 0 3 Sn 0 7 O 2/Ti and least on RuO 2/Ti. Voltammograms obtained in the polarisable region are used to characterize the different electrodes. Further more an analysis of the catalytic activity and reaction kinetics of the developed electrodes in NaCl are presented.

关键词： Catalyst Cl_(2) evolution Ruthenium oxide

PREDICTION OF THERMODYNAMIC PROPERTIES OFTHE FeO-CaO-SiO_2 MELTS FROM WILSON EQUATION

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 39-44页

作者： D.P.Tao x.W.yang Kunming Univ of Science and Technology Kunming China

An attempt was made to use the Wilson equation to predict the thermodynamic properties of the FeO-CaO-SiO2 melts at 1673 and 1873K. The activities of component FeO in the ternary melts at a given temperature were found to be conveniently calculated from the equation only with related binary parameters at different *** predicted values are in agreement with the ternary experimental data.

关键词： thermodynamic property FeO-CaO-SiO_2 melt Wilson equation

Leaching of rare Earth elements from an Illinois basin coal source

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Journal of Rare Earths 2019年第3期37卷 312-321页

作者： x.yang J.Werner R.Q.Honaker Department of Mining Engineering University of Kentucky

The existence of rare earth elements(REEs) in coal sources at elevated concentrations has been the focus of several studies over the past decade. However, limited research has been conducted on methods to recover and refine the REEs. This paper reports the results of a detailed study into the potential of selectively recovering REEs in an Illinois basin coal source by leaching. Leaching characteristics are obtained for several segments obtained from a core sample as well as three different reject materials collected at a coal processing plant. Using a 1.2 mol/L sulfuric acid solution at 75 ℃,over 60% REE recovery is achieved from the direct floor and an inner parting material as well as the coal-rich core segments that are pretreated by low-temperature plasma oxidation to obtain access to the microdispersed mineral matter. In the leachable parting material, fluorapatite is detected by xRD analysis,which is one of the more soluble phosphate minerals with a documented association with REEs. For the three plant reject samples, the leaching recovery values obtained for the heavy REEs are higher than those obtained for the light REEs under the standard leaching conditions and when 0.1 mol/L(NH_4)_2SO_4 was used to extract REEs by an ion exchange mechanism. Thermal activation by roasting or chemical activation by pretreatment using 8 mol/L NaOH solution increases the total REE recovery with significantly higher gains obtained for the light REEs. Leaching kinetics are relatively fast within the first 2 h and then slow to provide relatively low overall recovery values under the standard test conditions for the coarse and fine reject samples. However, significantly higher recovery values are realized when treating mixed-phase(middling) particles existing within the coarse reject material.

关键词： Leaching Coal Thermal activation Chemical activation Rare earth elements