A novel approach to investigate surface roughness evolution in asymmetric rolling based on three dimensional real surface

Surface roughness affects the friction behaviour, stress distribution and surface quality; moreover this influence is more significant when scaling down the strip size. A novel approach has been proposed to investigate the surface roughness in asymmetric rolling based on Finite Element Analysis (FEA). Evolution of asperity flattening, contact area ratio and surface roughness is investigated under various simulation rolling conditions. The model reviewed numerical solutions for real surfaces with asperities of arbitrary shape and varying size and height distributions. The rolling characterization has also been identified for asymmetric rolling. The difference of change in surface roughness for upper and lower strip surface is large during rolling. The effect of the speed asymmetry factor on strip bending has been established. An increase of the speed asymmetry factor causes an increase in the strip curvature, while the force parameters decrease with increasing asymmetry factor. The speed asymmetric factor influences the strip bending significantly. It is the first attempt to carry out this kind of research in surface roughness based on real surface during asymmetric rolling of thin strip. 2013 Elsevier B.V

Foil Rolling: A New Interpretation of Experimental Results

This paper explores a new interpretation of experiments on foil rolling. The assumption that the roll remains convex is relaxed so that the strip profile may become concave, or thicken in the roll gap. However, we conjecture that the concave profile is associated with phenomena which occur after the rolls have stopped. We argue that the yield criterion must be satisfied in a nonconventional manner if such a phenomenon is caused plastically. Finite element analysis on an extrusion problem appears to confirm this conjecture

Job stress reduction therapies

Job stress among healthcare workers has received more attention in recent years, perhaps because these professionals are prime candidates for high stress levels. The immediate effects of brief massage therapy, music relaxation with visual imagery, muscle relaxation, and social support group sessions were assessed in 100 hospital employees at a major public hospital. The effects of the therapies were assessed using a within-subjects pre-post test design and by comparisons across groups. Groups reported decreases in anxiety, depression, fatigue, and confusion, as well as increased vigor following the sessions. That the groups did not differ on these variables suggests that these particular therapies, when applied for short periods of time, are equally effective for reducing stress among hospital employees