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Abstract: The traditional approach to construct CNC machine tools has been to use rotary drive motors and ballscrews to achieve table motion. Linear motors offer several advantages over this approach, including low inertia, better performance, increased accuracy and reduced complexity. This article describes how a low cost, high-speed cutting machine was built using linear motors in order to conduct machining tests on a composite material. The machine configuration was a gantry type X/Y motion system on which a high-speed electrospindle was mounted. Both were interfaced with a standalone CNC controller for which a Microsoft Windows based interface was written in C++. The machine has the usual functionality of a CNC router and is capable of table speeds of over 40m/min and a spindle speed of 30,000rev/min. The machine is used to carry out tests on tool wear monitoring as part of an ongoing research project in the university. [Copyright &y& Elsevier]

There has been a growing interest in the influences on undergraduate performance in recent years as a result of the increasing diversity of students entering third-level education and an ever increasing emphasis on the development of a robust knowledge economy. This paper investigates the influence of students’ dominant interest types and prior academic achievement on undergraduate performance in an Irish university. Holland's Self-Directed Search (SDS) interest inventory was completed by 308 students drawn from three, second year undergraduate programmes in engineering, nursing and teaching. The impact of dominant interest types and prior academic achievement on the performance of these students in their second year was then investigated using correlation and linear regression analyses. When combined, student interests and prior academic achievements were found to account for between 38% and 50% of the variance in undergraduate performance for students in these three undergraduate programmes. [ABSTRACT FROM PUBLISHER]