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Co-evolutionary design of discrete structures based on the ant colony optimization

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Progress in Natural science:Materials International 2007年第9期17卷 1082-1094页

作者： Tao Zhenwu and Xiao Renbin(CAD Center,huazhong university of {2. and technology,wuhan 430074,china) CAD Center Huazhong University of Science and Technology Wuhan 430074 China

In order to optimize the sizing and topology of discrete structures together and resist the combinatorial explosion of the solution space,a co-evolutionary design(CED)method based on ant colony optimization(ACO)for discrete structures is *** tailored ant colony optimization for the sizing of structures(TACO-SS)and the tailored ant colony optimization for the topology of structures(TACO-TS)are implemented *** analysis shows that the computation complexity of each sub-process in CED based on ACO above is polynomial and it guarantees the efficiency of this *** the parameter settings in TACO-SS and TACO-TS are discussed,the convergence history of a sub-process is studied through an instance in ***,according to the design examples of the 10-bar and 15-bar trusses under different cases,the effectiveness of the CED based on ACO is validated and the effects of the loads and the deflection constraints on the co-evolutionary design are discussed.

关键词： evolutionary design ant colony optimization sizing optimization topology optimization

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. institute of laser Physics and Chemistry, Sichuan {2., Chengdu 610064, china 2. Department of Physics, Luoyang Normal College, Luoyang 47102., china 3. State Key Laboratory of laser technology, huazhong university of science and technology, wuhan 430074, china Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 1. institute of laser Physics and Chemistry Sichuan University 610064 Chengdu China 2. State Key Laboratory of laser technology Huazhong University of Science and Technology 430074 Wuhan China 3. Department of Physics Luoyang Normal College 471022 Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

AN IMPLICIT SCHEME FOR INCOMPRESSIBLE LBGK MODEL

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Journal of Hydrodynamics 2005年第3期17卷 330-337页

作者： DURui SHIBao-chang WANGGuang-chao LIUHong-juan DepartmentofMathematics HuazhongUniversityofScienceandTechnologyWuhan430074China DepartmentofMathematics HuazhongUniversityofScienceandStateKeyLaboratoryofCoalCombustionHuazhongUniversity430074China／／TechnologyWuhan430074ChinaofScienceandTechnologyWuhan

In this paper, an implicit scheme (also called the θ method) was proposed for the Lattice Bhatager-Gross-Krook (LBGK) model simulating incompressible flows. The new parameter θ made the model more flexible. Through the Chapman-Enskog procedure the impressible Navie-Stokes equations could be recovered with the coupled kinetic viscosity. Boundary conditions were treated briefly and it kept the numerical accuracy of the Lattice Boltzmann Method (LBM). The two-dimensional Poiseuille flow was simulated with different values of the parameters. It is found that the numerical accuracy and stability of the implicit scheme can be improved if some adaptable parameters are chosen.

关键词： Lattice Boltzmann Method (LBM) implicit scheme θ-Lattice Bhatager-Gross-Krook (LBGK) model Poiseuille flow

A low frequency piezoelectric power harvester using a spiral-shaped bimorph

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 649-659页

作者： HU Yuantai1,2.HU Hongping2.& YANG Jiashi3 1. institute of Mechanics and Sensing technology,Central South {2.,Changsha 410083,china 2. Department of Mechanics,huazhong {2. of science and technology,wuhan 430074,china 3. Department of Engineering Mechanics,{2. of Nebraska,Lincoln,NE 68588-052.,USA 1. institute of Mechanics and Sensing technology Central South University Changsha 410083 China 2. Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China 3. Department of Engineering Mechanics University of Nebraska Lincoln NE 68588-0526 USA

We propose a spiral-shaped piezoelectric bimorph power harvester operating with coupled flexural and extensional vibration modes for applications to low frequency energy sources. A theoretical analysis is performed and the computational results show that the spiral structure has relatively low operating frequency compared to beam power harvesters of the same size. It is found that to optimize the performance of a piezoelectric spiral-shaped harvester careful design is needed.

关键词： spiral-shaped bimorph,piezoelectric harvester,power density.

LAMINATED PIEZOELECTRIC PLATE FOR ACTIVE UNDERWATER ACOUSTIC CONTROL

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Acta Mechanica Solida Sinica 2001年第4期14卷 306-311页

作者： Zhao Hanzhong (Department of Mechanics,huazhong university of {2. and technology,wuhan 430074,china) Department of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

The pressure reflected from a bi-laminated piezoelectric plate hasbeen determined using the Thomson-Haskell matrix method. The plate iscomposed of a piezoelectric layer with grounded vacuum and An elasticlayer in contact with the fluid. An incident plane wave in the fluidmedium strikes the plate at dif- Ferent angles. The required electricpotential across the piezoelectric layer to cancel the reflectionfrom the Fluid/elastic boundary has been determined for thepiezoelectric material PZT-5 at various thickness parame- Ters andincident frequencies.

关键词： underwater acoustic control laminated piezoelectric plate acousticscattering acoustic radiation

ACOUSTIC REFLECTION FROM A BAFFLED ELASTIC/PIEZOELECTRIC PLATE

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Acta Mechanica Solida Sinica 2002年第2期15卷 156-162页

作者： Zhao Hanzhong (Department of Mechanics,huazhong university of {2. and technology,wuhan 430074,china) Department of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

A finite difference/boundary integral procedure to determine theacoustic reflected pressure from a fluid-loaded bi-laminated plate isdescribed. The bi-laminate is composed of a piezoelectric layer andan elastic layer in contact with the fluid, and is held by anacoustically hard baffle. In the numerical model, the fluid pressureat fluid/solid interface is replaced by a continuum of point sourcesweighted by the normal acceleration of the elastic plate, and thegoverning equation system is solved in the solid domain.

关键词： acoustic reflection baffled palte finite difference boundary integral

DEFICIENT INFORMATION MODELING OF MECHANICAL PRODUCTS FOR CONCEPTUAL SHAPE DESIGN

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 1-5,26页

作者： Liu Jihong Shu Huilin CAD Center，huazhong university of {2. and technology，wuhan 430074，china CAD Center Huazhong University of Science and Technology Wuhan 430074

In allusion to the deficient feature of product information in conceptualdesign, a framework of deficient information modeling for conceptual shape design is put forward,which includes qualitative shape modeling (a qualitative solid model), uncertain shape modeling (anuncertain relation model) and imprecise shape modeling (an imprecise region model). In theframework, the qualitative solid model is the core, which represents qualitatively (using symbols)the conceptual shapes of mechanical products. The uncertain relation model regarding domainrelations as objects and the imprecise region model regarding domains as objects are used to dealwith the uncertain and imprecise issues respectively, which arise from qualitative shape modeling orexist in product information itself.

关键词： Conceptual shape design Qualitative solid model Spatial cognition

A New Multisoliton Solution to (2.1)-Dimensional KdV Equation

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Communications in Theoretical Physics 2004年第5期41卷 669-670页

作者： PENG Yan-Ze~(1,2. 1 Department of Mathematics,huazhong university of {2. and technology,wuhan 430074,china2.Department of Mathematics and Physics,Henan university of {2. and technology,Luoyang 471003,china Department of Mathematics and Physics Henan University of Science and Technology Luoyang 471003 China

A new multisoliton solution to the(2.1)-dimensional KdV equation is obtained by means of the truncatedPainleve expansion method and a direct ansatz *** new exact solution is periodic in the propagating directionx and exponentially decaying in y and thus it is called periodic solitons.A typical spatial structure of it is illustrated bythe figures.

关键词： (2.1)-dimensional KdV equation periodic solitons truncated Painleve expansion method

LAMINATED VISCOELASTIC PLATE WITH INCLUSIONS FOR PASSIVE UNDER-WATER ACOUSTIC CONTROL

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Acta Mechanica Solida Sinica 2002年第1期15卷 23-29页

作者： Zhao Hanzhong (Department of Mechanics,huazhong university of {2. and technology,wuhan 430074,china) Department of Mechanics Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

The effectiveness of a fluid-loaded sandwiched viscoelastic layerin suppressing acoustic scat- tering and radiation has been estimatedusing the Thomson-Haskell matrix method. The GU (Gaunaurd andUberall) resonance theory has been adopted to handle three types ofviscoelastic substrates with air -filled in- Clusions. The effects ofthe varying thickness of the substrates, the volume fractions of theinclusions and fre- Quencies of incident waves have been studied todetermine the optimal strategies of signal reduction. In theInvestigation, the monopole resonance phenomena of the inclusionshave been taken into account.

关键词： underwater acoustic control laminated viscoelastic plate air-filledinclusion