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In this paper, a numerical model of elastohydrodynamic lubrication (EHL) in the line contact which happens on the surface of particle-reinforced composites is given. The influence of the particle size and burial depth on the EHL is studied. According to the influence of the structural parameters on the friction coefficient of the EHL contact, the structural parameters of the particles in the composites are optimized and the proper region of the parameters is obtained. The displacement and stress in elastic field caused by the uniform eigenstrains in the particles are described in terms of Galerkin vectors with the interactions between the particles are ignored. A coupling method of particle reinforced composites problem and EHL problem is presented, a new film thickness function is given considered the uneven elastic deformation caused by the presence of the particles. Finally, the presentation of film thickness and fluid pressure of the EHL explains that appropriate particle size, particle burial depth and particle distance can effectively reduce the friction coefficient. The lubrication behavior between the contacted surfaces can be improved under the heavy load.

The traditional calibration paradigms fail to give reliable and accurate results in case of low-quality 2D planar calibration plates. In this paper, an active method is proposed by employing an LCD panel for camera calibration. This method automatically generates a sequence of virtual patterns in different views by pre-defined transforms without manually manipulation or other equipment’s help to move the patterns. Then, the projections of virtual patterns are captured by a camera. The homography between projective patterns in virtual world coordinate and their images is calculated directly to obtain the camera parameters. Experimental results show that the calibration error is 0.018 pixel in terms of mean re-projection error by using 18 virtual patterns, which is significantly less than the state-of-the-art methods. The proposed scheme makes camera calibration flexible and easy to use.

The plastic zones of crack tips play a significant role in the fracture behavior of material. This paper proposes a semi-analytic solution for the plastic zones and stress distribution of an infinite space with multiple cracks and inhomogeneous inclusions under remote stress. In this solution, cracks can be treated as a distribution of edge dislocations with unknown densities according to the distributed dislocation technique, while inhomogeneous inclusions can be modeled as homogeneous inclusions with initial eigenstrain plus the unknown equivalent eigenstrain by using the equivalent inclusion method. These unknowns can be obtained by using the conjugate gradient method. The plastic zones ahead of crack tips are one-dimensional slender strips, and their sizes can be determined by canceling the stress intensity factor (SIF) due to the closure stress and that due to the applied load based on the Dugdale model of small-scale yielding. It is found that the plastic zones of crack tips are significantly affected by Young’s modulus and the positions of inhomogeneous inclusions.