THE EXPERIENCE OF FLOW IN COMPUTER-MEDIATED AND IN FACE-TO-FACE GROUPS

This paper proposes that optimal flow, based on a cognitive theory of human motivation provides a useful measure of individuals\u27 experiences as they participate in group work. Individuals\u27 experiences of flow, a state of being characterized by involvement in and enjoyment of a task, were determined to be significantly greater in computer-mediated groups than in face-to-face groups. Variables associated with flow included perceived control, task challenge, and required skill during a problem-solving activity performed by fifty-nine undergraduate business students in both settings. The level of skill was found to be positively linked with perceived control in both face-to-face and computer-mediated groups. Perceived control in turn, was positively linked with the flow experience in both groups. Results indicate that while skill is important in explaining flow in the face-to-face task, the perceived challenge is important in explaining flow in the computer-mediated task. Suggestions are offered for future research on flow and computer-supported collaborative work

Comparative study between wear of uncoated and TiAlN-coated carbide tools in milling of Ti6Al4V

As is recognized widely, tool wear is a major problem in the machining of difficult-to-cut titanium alloys. Therefore, it is of significant interest and importance to understand and determine quantitatively and qualitatively tool wear evolution and the underlying wear mechanisms. The main aim of this paper is to investigate and analyse wear, wear mechanisms and surface and chip generation of uncoated and TiAlN-coated carbide tools in a dry milling of Ti6Al4V alloys. The quantitative flank wear and roughness were measured and recorded. Optical and scanning electron microscopy (SEM) observations of the tool cutting edge, machined surface and chips were conducted. The results show that the TiAlN-coated tool exhibits an approximately 44% longer tool life than the uncoated tool at a cutting distance of 16 m. A more regular progressive abrasion between the flank face of the tool and the workpiece is found to be the underlying wear mechanism. The TiAlN-coated tool generates a smooth machined surface with 31% lower roughness than the uncoated tool. As is expected, both tools generate serrated chips. However, the burnt chips with blue color are noticed for the uncoated tool as the cutting continues further. The results are shown to be consistent with observation of other researchers, and further imply that coated tools with appropriate combinations of cutting parameters would be able to increase the tool life in cutting of titanium alloys