力学进展

SOME PROBLEMS IN COMPUTATIONAL INTELLIGENCE AND INVERSE PROBLEMS IN MECHANICS

2000, 30(3): 321-331. doi: 10.6052/1000-0992-2000-3-J1998-024

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Computational intelligence is the computational simulation of the bio-intelligence, which includes artificial neural networks, fuzzy systems, and evolutionary computations. In this paper, some advances in the computational intelligence and inverse problems in mechanics are briefly discussed and reviewed, based partly on author's research work.

THE STRUCTURE DYNAMIC ANALYSIS BY ADAPTIVE FINITE ELEMENT METHOD

2000, 30(3): 332-342. doi: 10.6052/1000-0992-2000-3-J1998-025

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The adaptive finite element method in structure dynamic analysis is mainly used to study the error estimation in finite element dynamic analysis and establish adaptive finite element mesh generation procedure for dynamic analysis of complex structure. In this paper, the authors first review the important development in dynamic problem of structure by adaptive finite element method, including error estimation and adaptive strategy for the analysis of the free vibration and dynamic response to the external lo...

STOCHASTIC FINITE ELEMENT METHOD AND STRUCTURAL RELIABILITY

2000, 30(3): 343-350. doi: 10.6052/1000-0992-2000-3-J1998-026

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The paper presents a brief introduction and review for the finite element analysis and reliability analysis of stochastic structures, which includes the discretization of stochastic structures, the solution of stochastic finite element control equations, stochastic finite element reliability methods and the other methods of reliability analysis of stochastic structures. Some unsolved problems are discussed.

STABILITY, BIFURCATIONS AND CHAOS IN SPACECRAFT ATTITUDE DYNAMICS

2000, 30(3): 351-357. doi: 10.6052/1000-0992-2000-3-J1998-027

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This paper reviews some nonlinear problems in spacecraft attitude dynamics, which include attitude stability of multibody spacecraft, spacecraft with flexible bodies, and spacecraft containing liquid. The progresses in studying bifurcations and chaos of spacecraft attitude motions are surveyed. Some promising directions for further studies are proposed.

THE VAKONOMIC MODEL AND CHETAEV'S MODEL IN ANALYTICAL DYNAMICS OF NONHOLONOMIC SYSTEMS

2000, 30(3): 358-369. doi: 10.6052/1000-0992-2000-3-J1998-028

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The Chetaev's model and Vakonomic model are described in this paper. It is proved that the model of Hertz, Capon and Lindelof are identical to Vakonomic model while the model of Holder, Pars and Chaplygin are identical to Chetaev's model. The fact that Vakonomic model and Chetaev's model exist simultanously can be traced back to the early days of non-holonomic mechanics. These two models cause two problems: the d-δ and ∫-δ permutable problems. A review of the contribution of scholars in China to unify these...

METHODS OF TIME-VARYING STRUCTURAL PARAMETER IDENTIFICATION

2000, 30(3): 370-377. doi: 10.6052/1000-0992-2000-3-J1998-029

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The methods of time-varying parameter identifications and some typical applications including autocontrol theory field are reviewed. The theoretical and practical aspects are discussed, specially the on-line identification technique and the neural net technique. The wavelet transform for time-varying modal parameter identification is also presented. Finally, some further research trends are pointed out.

REVIEW ON ELASTIC WAVE PROPAGATION UNDER COMPLEX INTERFACE (INTERFACE LAYER) CONDITIONS4

2000, 30(3): 378-390. doi: 10.6052/1000-0992-2000-3-J1998-030

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Interfaces (or interface layers), which exist widely in various materials and structures, have different forms. The wave propagation under various interface conditions is of both theoretical and practical importance. This paper reviews the current development of the investigations on the wave propagation with complex interface models such as the perfectly bonded interfaces, weakly bonded interfaces (or interface layers) and contacting interfaces, etc. The discussion is focused on the establishment of the in...

MEASUREMENTS ON MECHANICAL PROPERTIES OF MATERIALS WITH MICRO/NANO-METER SCALE

2000, 30(3): 391-399. doi: 10.6052/1000-0992-2000-3-J1998-031

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With respect to evaluating the mechanical properties of nano, micro-, low-dimentional materials, this paper introduced several methods for measuring mechanical properties, such as hardness, elastic modulus, yield stress, creep, fatigue parameters, with newly advanced appratus(AFM/ Nano-Indenter/STM) and mechanical analyses.

CYCLIC STRESS-STRAIN RESPONSE OF COPPER BICRYSTALS

2000, 30(3): 400-414. doi: 10.6052/1000-0992-2000-3-J1998-032

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TO investigate the difference in fatigue behavior between single- and poly-crystals, it is necessary to reveal the fatigue damage mechanism of bi-crystals. Recent research progress in fatigue behavior of copper bi-crystals with different component crystals and grain boundaries was summarized. A model of grain boundary strengthening in copper bicrystals with parallel grain boundaries induced by the cyclic deformation was proposed by using the concept of Schmid factor and the grain boundary affected zone. By ...

CURRENT STATUS OF STUDIES ON DAMAGED METALLIC STRUCTURES BONDED WITH COMPOSITE PATCHES

2000, 30(3): 415-424. doi: 10.6052/1000-0992-2000-3-J1998-033

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Bonded composite repair has been recognized as an efficient and economical method to extend the service life of damaged aircraft metallic structures. The advantages and disadvantages, as well as its technical essentials are discussed in detail. They include the selection of adhesive, design of patch material and parameters, surface treatment, nondestructive inspection and experimental verification. The current status of this advanced technique and its applications in the aircraft structures are also discus...

EXPERIMENTAL AND THEORETICAL STUDIES ON THE COUNTER GRADIENT TRANSPORT PHENOMENA IN TURBULENT FLOWS

2000, 30(3): 425-432. doi: 10.6052/1000-0992-2000-3-J1998-034

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Counter gradient transport phenomena for momentum and passive scalar in turbulent flows are an important subject in the research of turbulence. It is of great theoretical significance and serves as a practical background. This article summarizes the experimental and theoretical results on counter gradient transport phenomena. Finally some subjects for further studies are suggested.

THE MECHANOCYTOBIOLOGICAL MECHANISMS OF LOADING-INDUCED BONE FORMATION

2000, 30(3): 433-445. doi: 10.6052/1000-0992-2000-3-J1998-035

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The structure and the function of bones are dependent to a large extent on its mechanical environment, and this point of view has been widely accepted. Since Wolff presented his famous Law of Bone Transformation, the relationship between the bone formation and the mechanical loading has become an important question of biomechanics. Numerous animal experiments demonstrated a clear linkage between them. However, the mechanocytobiological mechanisms were poorly understood. The loading studies on in vitro cul...

ADVANCES IN THE STUDY OF NON-FOURIER HEAT CONDUCTION

2000, 30(3): 446-456. doi: 10.6052/1000-0992-2000-3-J1998-036

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Rapid transient heat conduction is an emerging area in modern high and new technologies such as ultrashort pulse laser heating, rapid solidification of metals. Under such a condition when the time scale of the heating process is extremely small, the non-Fourier effects in the heat conduction become significant. The advances in the study of mechanisms, modeling, applications and experiments in non-Fourier heat conduction are reviewed in this paper. The topics for further investigations are suggested.

DEVELOPMENT OF GEOPHYSICAL FLUID DYNAMICS: THE INFLUENCE OF LABORATORY EXPERIMENTS

2000, 30(3): 457-470. doi: 10.6052/1000-0992-2000-3-J1998-037

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Advances in geophysical mechanics, especially through laboratory experiments are systematically introduced for atmosphere, ocean and newly emerging geology systems in the present article. A wide range of interesting phenomena such as plume, turbulent entrainment, density flows, oceanic circulation, mixing layer, double diffusion, salt fingering, magma chamber, mantle convection, hot spots are addressed in detail. Not only they are of significance for understanding the mechanism of buoyancy-driven convection...

2000, 30(3): 471-471. doi: 10.6052/1000-0992-2000-3-J1998-258

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2000, 30(3): 472-475. doi: 10.6052/1000-0992-2000-3-J1998-259

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2000, 30(3): 476-477. doi: 10.6052/1000-0992-2000-3-J1998-260

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2000, 30(3): 476-477. doi: 10.6052/1000-0992-2000-3-J2000-055

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2000, 30(3): 478-478. doi: 10.6052/1000-0992-2000-3-J1998-261

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2000 Vol. 30, No. 3

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