Professor Malcolm Hawksford has had a couple of papers published recently.
Objective Grading of Nonlinear Processing in Virtual-Bass Systems" with Nay Oo,
Woon-Seng Gan. Abstract: Nonlinear devices (NLDs) can be used in
bass-enhancement systems to create psychoacoustic-derived virtual-bass extension
by synthesizing harmonics of a missing fundamental. Problematically, such
NLD-related distortions can also form perceptual distortion. Earlier studies
reveal that although objective measurement scores quantify bass enhancement and
harmonic distortion, there is weak correlation with subjective perception. An
in-depth subjective study is presented on NLD-specific distortion linked to
perception and bass-intensity enhancement and then extended to correlate the
Rnonlin distortion model to subjective data. Nonlinear regression computes
Rnonlin-equation coefficients to enable a metric for audibility of NLD-dependent
distortion. Recommendations follow for NLD sets that achieve good bass
performance with low perceived distortion.
Psychoacoustic Correction for Problematic Room-Modes Using Nonlinear Bass
Synthesis" with Adam Hill. Abstract: Small room acoustics are
characterized by a limited number of dominant low-frequency room-modes that
result in wide spatio-pressure variations that traditional room correction
systems may find elusive to correct over a broad listening area. A
psychoacoustic-based methodology is proposed whereby signal components
coincident only with problematic modes are filtered and substituted by virtual
bass components to forge an illusion of the suppressed frequencies. Although
this approach can constitute a standalone correction system, the impetus for
development is for use within well-established correction methodologies. A
scalable and hierarchical approach is studied using subjective evaluation to
confirm uniform wide-area performance. Bass synthesis exploits parallel
nonlinear and phase vocoder generators with outputs blended as a function of
transient and steady-state signal content.
Three Year 1 CSEE students from north Essex have received a prestigious
scholarship to support their studies. They won Eliahou Dangoor
scholarships worth £1,000. The scholarships were established by
philanthropist Dr Naim Dangoor to support the best students across the country
to help them realise their potential, and are only open to students at Russell
Group or 1994 Group universities.
Ben Royall has passed his PhD after his viva in December.
The title of his thesis is GaInNAs / GaAs Multiple Quantum Well and n-i-p-i
Solar Cells. He was supervised by Prof Naci Balkan and his examiners were
Prof Judy Rorison (Bristol) and Dr Nick Zakhleniuk (Essex). Congratulations to
Wilson has passed his PhD with editorial corrections only. He was
supervised by Palani Ramaswamy and his examiners were Francisco Sepulveda
(Essex) and Damien Coyle (Ulster).
John was funded by an EPSRC Studentship and his work was on establishing a
viable brain-computer interface (BCI) paradigm using steady state evoked
potentials. Using phase spectral information, which is usually discarded,
John was able to design an advanced system that mainly alleviated the need for
robust training periods while maintaining comparable performance. His work
(jointly with Plymouth) resulted in a successful trial with a locked-in patient
that enabled music control through the BCI device (this work recently received
wide national and international press coverage).
John was also the recipient of the prestigious IET William James Award for this
year. This competitive award is presented to the student whose PhD
research shows the most potential to contribute towards the development and
improvement of the biomedical engineering field. Many congratulations to
The seminar programme for the Spring term will be available shortly.