Audio and Acoustic Signal Processing, especially Spatial active noise control, Audio solution for Human-Unmanned Aerial Vehicle (UAV) interactions, Sound field Reproduction, Room Acoustics, Spatial Audio Solution for Virtual and Augmented Reality, and Microphone Arrays.
Digital Design and Embedded systems, especially Embedded Automatic Test and Control Systems and Embedded Audio Systems.
As Director of the Rolls-Royce UTC in Propulsion Systems Noise Alec develops, leads and participates in a range of European and UK collaborative research programmes in the field of aeroplane noise, with particular emphasis on aeroengine noise sources and sound propagation.
While at Rolls-Royce Alec played a pioneering role in the application of aerodynamic CFD codes to predict turbomachinery tone noise generated by real engineering geometries, and Alec’s own research at the University of Southampton still centres on the development and application of analytic and numerical modelling techniques to real-world engineering issues and opportunities.
An example of Alec’s current research is the development of a new prediction method based on eigen analysis. Eigen analysis has been used for many years to provide a fast, computationally efficient method for predicting noise propagation in ducts, but the methods used have been limited to simplified geometries and mean flow which has limited their usefulness in practice. The new method being developed retains the computational efficiency of previous methods, but can be applied to any smoothly varying mean flow and duct geometry. The initial target of the research is to provide a method to predict acoustic propagation through a three-dimensional aeroengine intake at a computational cost that permits multiple calculations during the design optimisation process.
Much of cochlear physiology and pathophysiology remains poorly understood. For example, how do the 3000 rows of active outer hair cells interact with each other and with other cochlear structures to amplify the waves in the cochlea that allow us to hear? How are the motions of these cochlear structures related to the otoacoustic emissions that we can measure in the ear canal? What role do the efferent nerves play? What are the changes brought about by pathology? The long term research goal is to understand human cochlear physiology in both normal and pathological conditions with a view to aiding the development of improved clinical diagnostic techniques and treatments. One approach to improving our understanding of the electro-mechanical aspect of physiology is to develop realistic models of the cochlea. These should capture the essential hydrodynamics, structural dynamics, and electrical processes involved in cochlear physiology. The non-linear mechano-electrical and electro-mechanical transduction processes are key aspects of the physiology where our understanding remains at a basic level. The ways in which these models may be useful clinically are: to aid the development of treatments, or prostheses for hearing impairment, to improve our ability to interpret clinical results (such as measurements of otoacoustic emissions or electrophysiology), to aid the development of new clinical tests of cochlear function.
His research interests are in biomedical signal processing with applications in neurophysiology and cardio-vascular and cerebro-vascular control. Specific topics are:
Blood flow control in the brain (how does the brain regulate is own blood supply and how to detect impairment of this function).
Auditory evoked potentials (methods to detect the small electrical responses of the brain to auditory stimulation for the assessment of various hearing disorders).
