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The purpose of this paper is to study the contact-impact between ellipse and ground. The contact-impact position is non-fixed when the ellipse is rotated. Ellipse equations are built by generalized coordinates. The contact point is estimated by the elliptical geometric characteristics and equations. Do dynamics analysis by the method of continuous processing which uses spring damper mode in this point. This spring damper mode is based on the nonlinear spring damper model of Hunt-Crossley. Friction is ignored in this paper. Finally the numerical solution is given by Matlab.

The oblique impact between cylinder and ground with friction is studied. The applicability and limitation of the classical impact theory of rigid body are verified by building oblique impact between cylinder and ground of flexible model and rigid model respectively. The finite element method is used to build the flexible model of oblique impact between cylinder and ground. It is analyzed that the sliding mode of the contact point, the direction of the friction force and Newton coefficient of restitution during collision varying with different tangential velocity. Comparing the result with the classical impact rigid model, it is proved that numerous sliding modes are existent during collision. Additionally, the applicability of the rigid model is proved in unidirectional sliding mode.

The platelike Co3O4/carbon nanofiber (CNF) composite materials were synthesized by the calcination of β-Co(OH)2/CNF precursor prepared by a surfactant-free hydrothermal method. As negative electrode materials for lithium-ion batteries, the platelike Co3O4/CNF composites can deliver a high reversible capacity of 900 mAh g-1 for a life extending over hundreds of cycles at a current density of 100 mA g-1. The high Li-storage capacity and excellent cycling performance for Co3O4/CNF composite materials may mainly attribute to the beneficial effect of the CNFs addition on enhancing structural stability and electrical conductivity of Co3O4 platelets.

The purpose is to study the variational method for impact problem of a non-ideal constraint system. Compared to an ideal constraint system, a non-ideal constraint system has more practical engineering background, but it contains unknown non-ideal constraint forces, which usually can be written as the function of ideal constrained forces. The existing analytical method on ideal constraint systems does not contain constraint forces. The non-ideal constraint forces are considered for impact problems in the variational principle, and then by method of Lagrange multipliers, equations for impact motion of a holonomic system and an expression of the kinetic energy variation during the impact motion are obtained.

The relationship between the morphology and protective action of hot-dip aluminizing coatings on Q235 steel have been investigated by SEM, EDS and EIS in 3.5 wt% NaCl aqueous solution. The results indicated that the anti-corrosion performance of the hot-dip aluminizing coatings using steel substrate rinsed by the distilled water at 25 oC was higher than that at 80 oC. The evolution of localized corrosion from pitting to exfoliation corrosion has been found on the aluminum coating surface during immersion, and corresponding equivalent circuit models were proposed to fit the EIS data in the initiation and propagation stages of corrosion process.

Electrolytic fixation of CO2 was investigated by electrocarboxylation of organic halides (a), and four esters (I, II, III, IV) were obtained in moderate yields. Electrochemical reduction esterifications of RX in the presence of CO2 were carried out on nanocrystalline TiO2-Pt electrode. The electrochemical behavior of RX in the presence of CO2 was investigated by the technique of cyclic voltammetry, and the probable reaction mechanism was proposed.

The free vibration model of a rotating composite thin-walled closed-section beams is presented in this paper. The two-dimensional cross-sectional analysis based on the variational-asymptotical method(VAM) is combined with the Hamilton’s principle to derive the equations of motion and associated boundary conditions of the beams. The Galerkin method is employed in order to solve the coupled differential equations. The natural frequency results obtained for the present model are compared with those of the existing models. Numerical results are obtained for the laminated composite cantilevered box beam with Circumferentially Uniform Stiffness(CUS) configuration, the effects of the fiber orientation, pitch and precone on the natural frequencies associated with coupled vibration modes are investigated.

For two-body collisions, it has been recognized that the coefficient of restitution is not a material property but is affected by initial relative velocity at the contact point as well as orientation of the colliding bodies. This paper obtains expressions for the energetic coefficient of restitution in terms of initial conditions based on the methods of analytical mechanics for impacts of multi-rigid-body systems. We provide two examples. The first example is for two-body collision with friction to validate the rationality of the expressions given by this paper. The example used by Stronge (Mech. Struct. Mach. 29(2) (2001) 239) is served as the second example for comparison with Stronge (2001).

This paper proposes an efficient method, the hybrid localization scheme, to solve the problem of Macau license plate localization. The approach is based on the edge analysis and statistics. Considering the characteristics of Macau license plates, proper edge analysis thresholds are acquired by statistics. The characteristics of black background and various rang of the ratio are added to the hierarchical scheme to determine the final location area. The experiment shows that the accuracy is improved a lot comparing to the previous methods.

This paper proposes a novel and effective invariant shape representation by Radon and stationary wavelet transforms for images with complex inner shapes. The proposed method is invariant to general geometrical transformations. Instead of analyzing shapes directly in the spatial domain, the proposed method retrieves features in radon transform domain by statistical and spectral analysis to make shapes translation and size invariant. The stationary wavelet transform is used to make shapes rotation invariant. Experiment results show that the proposed shape representation is invariant to rotation, translation, and/or scaling changes for images with complex inner shapes, and outperforms the other existing methods with higher recognition rates.