ABSTRACT
An investigation into the inspection capabilities of in-field advanced ultrasound detection for use on ultra-thick (20 to 100 mm) glass fibre-reinforced polyester composites is presented. Plates were manufactured using custom moulding techniques, such that delamination flaws were created at calibrated depths. The full matrix capture technique with an on-board total focussing method was used to detect flaws scanned by a 0.5 MHz linear array probe. Flaw through-thickness dimensions were altered to assess the threshold for crack face separation at which delaminations could be identified. Furthermore, part thickness and in-plane flaw dimensions were varied to identify the inspection capability limitations of advanced ultrasonics for thick composites. The results presented in this study demonstrate an inverse relationship between the ability to find delaminations and plate thicknesses, with inspections successful at depths up to 74 mm. When the delamination thickness exhibited surface-to-surface contact, the inspection capability was reduced to 35 mm. There was an exponential decay relationship between the accuracy of the flaw depth measurement and plate thickness, likely due to the necessity of low probe frequencies. The effective inspection depth was determined to be in the range of 1 to 20 times the wavelength. It is speculated that the accuracy of measurements could be improved using probes with novel coupling solutions, and detectors with optimised signal processing/filtration algorithms.
ABSTRACT
In this study, two types of single polymer films have been inserted in a composite laminate to examine their toughening effects on mechanical properties. The first is a thermoplastic polyurethane (PU) film, and the second is an adhesive epoxy film featuring a polyester net. The laminates were manufactured either using a co-curing (CC) process or a secondary bonding (SB) process used for the epoxy film. Mode I and mode II interlaminar fracture toughness were measured for laminates manufactured by both processes and compared with the corresponding reference laminate toughness. A significant increase in both mode I and mode II toughness resulted when introducing a single PU film, approximately 290% and 50%, respectively. Similarly, the epoxy film improved the interlaminar fracture properties; the CC process produced an increase of 175% for mode II toughness, while the SB adhesive film showed an increase of 75% for mode II toughness.
ABSTRACT
OBJECTIVES: Previous studies have established that essential information is inconsistently provided during the transfer of extended care facility (ECF) patients to the emergency department (ED). The authors tested the hypothesis that a one-page, standard ECF-to-ED transfer form would change the rate of successful documentation of ECF patient information. METHODS: The design was a pre- and postintervention investigation. The setting was the Methodist Hospital ED, an urban teaching facility in Indianapolis, Indiana. The population included consecutive patients transferred from ECFs to the ED. The intervention consisted of the introduction of a one-page, standard ECF-to-ED transfer form that listed 11 data elements that are critical for patient care. The completed form was to be sent with patients transferred to the ED. Successful documentation was defined as the recording of at least nine of 11 data elements. RESULTS: In the preintervention period, the ED received 130 transfers from 41 ECFs. Sixty-five of 130 transfers were from ten ECFs, which were the targets of the intervention. In the postintervention period, 72 consecutive transfers from ten ECFs were studied. Postintervention, the proportion of transfers with successful documentation was 77.8% (56 of 72), an increase of 19.3% (95% CI = 4.0% to 34.7%) over the preintervention period. In 31.9% (23 of 72) of postintervention ED transfers, the transfer form was transported with the patient. Successful documentation was achieved in 22 (95.6%) of these 23 transfers. CONCLUSIONS: Use of a one-page, standard ECF-to-ED transfer form increased the amount of essential data provided to the ED.
