Colin Kestell

Virtual error sensing for active noise control in a one-dimensional waveguide: Performance prediction versus measurement (L)

Virtual error sensing is a novel active noise control technique, which is designed to produce a zone of attenuation remote from the physical error sensors. In this letter virtual sensing is investigated for tonal noise (both on and off resonance) in a long narrow duct. The performance of the virtual error sensors using real-time control is compared to the performance determined from an analytical model and the performance determined through the postprocessing of experimental data. Two examples of control using postprocessed experimental transfer function data are presented; the first relied on transfer functions measured using broadband noise and the second relied on transfer functions measured at discrete frequencies. The results highlight the significant errors encountered as a result of using broadband transfer functions in lightly damped enclosures.

Encouraging the adoption of education technology for improved student outcomes

Evidence in the literature indicates that the current generation of electronic learning and teaching aids can offer significant pedagogical advantages ranging from revision to improved feedback. As a result, many universities in Australia and worldwide, are investing heavily in modern teaching tools, often equipping lecture theatres with the latest multimedia facilities. However, at the same time, there are growing pressures on academic staff regarding the competing needs for their time spent on research and other commitments. Questions therefore arise as to whether these new education technologies are in fact welcomed and used by some academics, despite the reported advantages to the student learning experience when used effectively. To investigate this, several surveys of engineering staff and students regarding education technology were conducted to establish the perceptions of their impacts on student learning and scope of their use. Based on these results and a review of the literature, recommendations are proposed for effective strategies for academic staff who wish to adopt education technologies. The objective is to decrease the resistance of those academics that may not yet have embraced some of the more modern teaching technologies. This is done by demonstrating that if integrated into existing teaching practices in a systematic manner, any short-term increase in workload can be offset by longer term efficiencies, along with potential improvements to student understanding and satisfaction.

Effects of medical device legislation on innovation within Australian manufacturing companies

Summary Unlike many other industries in Australia, manufacturers of medical devices must meet strict regulatory requirements to be permitted to supply their products on the consumer market. With the introduction of the Therapeutic Goods Act and Medical Device Regulations, Australian manufacturers became legally obligated to follow specific principles of quality systems implementation in design, manufacturing and product delivery processes. A survey was conducted to determine manufacturers’ perceptions of the effects of the regulation on the product development practices within their companies. Results of the survey showed that the majority of respondents are anticipating or have already experienced mostly positive effects of the legislation on quality, reliability and safety of products and legal security of their companies. However, the respondents estimate that the legislation will negatively affect the cost of innovation and delivery time of new products to the market.

Active noise control of a single‐engine light aircraft cabin

Active noise control (ANC) shows success and potential in a growing number of commercial applications, one of which is aircraft cabin noise reduction. With the exception of utilizing ANC headsets, light aircraft, which to date offer a high noise environment, have been somewhat overlooked. The importance of weight minimization also prevents installing copious quantities of dampening and insulation materials as a passive noise control measure. While headsets are a pilot’s necessity and an obvious target for ‘‘localized’’ noise reduction, they are not conducive to either operator or passenger comfort. High noise levels not only render communication difficult but also contribute toward stress and fatigue. A more globalized region of reduced noise will be less restrictive and no doubt provide the occupants with more freedom of movement and overall comfort. Light aircraft operators boasting quieter cabins with a focus on customer comfort will no doubt have a distinct commercial advantage. Using flight trials an...