The Application of Microcomputers in Automated Arc Welding Systems
An overview is presented of the functions, capabilities, and operation of the microcomputer as it relates to automated arc welding. This is followed by examples of the use of the microcomputer ranging from automatic joint tracking to complete weld system programming and data logging. A discussion of future applications of the microcomputer in the role of full, adaptive weld automation is given.
Industrial Computer Vision in Japan
Japanese research in pattern analysis and machine intelligence has focused on industrial applications. A number of successful computer vision systems are now employed in Japanese manufacturing.
Numerical analysis of surface crack propagation in flexible pavements using XFEM and cohesive zone model
Surface initiated (top-down) cracking in the longitudinal direction of pavements has become a predominant mode of failure in thick asphalt pavements. Most previous researchers studied crack propagation using the traditional Linear Elastic Fracture Mechanics (LEFM) method by calculating the stress intensity factor around the crack tip. In this paper, Extended Finite Element Method (XFEM) was used to study the key factors causing surface initiated crack propagation under surface tension and/or shear. A two-dimensional (2-D) finite element (FE) model for a two-lane flexible pavement was built to predict pavement responses and crack propagation potential under various scenarios. It was found that surface tension is the major driving force for crack propagation when the crack is at some distance away from tire loading. The results show that the distance from the location of crack to tire loading, the depth and direction of the crack, and the modulus ratio between the hot-mix asphalt (HMA) layer and the base layer have significant influences on crack propagation under surface tension. On the other hand, this study shows that shear stress can induce surface initiated crack propagation near the loading area as the shear resistance of material becomes low at the high temperature.