Towards Automated Visual Inspection and Classification of Micro-Parts
The mechanical manufacturing of micro-parts is a challenging field of research. Because of high quality requirements and small tolerances, manufacturing processes have to be very stable and precise. In order to achieve high precision a suitable quality assurance concept is required. Only measured features can be used for statistical process control (SPC). Therefore, this paper presents a concept of an automated visual inspection and classification methods for micro-parts. Using confocal laser scanning microscopy, high-resolution 3D-height maps with depth selectivity are obtained. The identification of surface imperfections is done with a set of conventional image processing techniques. Afterwards, these kinds of surface defects are classified by the use of classification methods like decision trees.
Classification of size effects and similarity evaluating method in micro forming
Micro size effects are the particular phenomena in metal micro forming. Therefore, it is the point of the further research on micro-forming processing and theories. The experiential formulas and deformation theories of the conventional forming can be adopted to the micro-forming processing, on condition that the micro size effects are classified as micro size effects on material constitution and micro size effects on processing condition. On the basis of theory of similarity, a new concept, similarity precision is defined as similarity mete-wand of micro size effects. The similarity precision of two kinds of micro size effects above is demonstrated by adopting data of references, and application from conventional forming to micro forming is illustrated in terms of these methods of classifying and evaluating micro size effects.
Testing the Core Empirical Implications of Gottfredson and Hirschi's General Theory of Crime
In A General Theory of Crime, Gottfredson and Hirschi propose that low self-control, in interaction with criminal opportunity, is the major cause of crime. The research reported in this article attempts to test this argument while closely following the nominal definitions presented by Gottfredson and Hirschi. A factor analysis of items designed to measure low self-control is consistent with their contention that the trait is unidimensional. Further, the proposed interaction effect is found for self-reported acts of both fraud and force (their definition of crime). Inconsistent with the theory are (a) the finding that criminal opportunity has a significant main effect, beyond its interaction with low self-control, on self-reported crime and (b) the substantial proportion of variance in crime left unexplained by the theoretical variables. Suggestions are offered for modifying and expanding the theory.