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Real-time monitoring of carbon fibre composites during Automated Fibre Placement (AFP) manufacturing remains a challenge for non-destructive evaluation (NDE) techniques. An directional eddy-current (EC) probe with asymmetric transmit and differential receive (Tx-dRx) coils is designed, constructed and characterized to evaluate the detectability of out-of-plane wrinkles. Initial studies were conducted to determine suitable excitation frequencies and to analyse the impact of relative orientations of driver and pickup coils on wrinkle detectability. The probe configurations are evaluated experimentally and employ a new finite element modelling approach to better understand the relationship between eddy-current density and defect detection. The findings indicate that a probe configuration with an asymmetric driver coil normal to the material surface and aligned with the fibre directions, and with differential pickup coils 90 degrees to the scanning direction, shows the best capability for out-of-plane wrinkle detection, with SNR >20 for wrinkles over 1.3 mm in amplitude.

The goal of this study was to determine the effectiveness of the Piedmont Virginia Community College (PVCC) electronics program between 1995-1999 by answering the following questions: (1) did the students find employment in an electronics-related career upon graduation? (2) did they feel that the program provided them with an adequate level of workplace preparation? and (3) what aspects of the program could be changed to better prepare future students for the workplace? Thirty-four of 57 graduates responded to the survey. According to the survey results, approximately 8 of 10 graduates (79.4%) are currently employed in an electronics related career. The mean response of the overall satisfaction of the respondents with the level of workforce preparation was 4.53, which resides between "moderately satisfied" and "very satisfied." The mean satisfaction values in the skills areas of AC and DC circuits, electronic devices, digital electronics and computers indicated that the graduates were "very satisfied," whereas the mean values for electrical machines and electrical control systems/PLCs were significantly lower. Based on the results of the study, several recommendations are made including evaluation of the textbooks, laboratory assignments, laboratory equipment, instruction, and curricular content of the electrical machines and electrical control systems/PLCs courses to improve their transferability to the workplace environment and greater collaboration with the electronics industry. (JA)