Thomas Witelski

Thomas Witelski is a Professor in the Department of Mathematics at Duke University. After undergraduate training in engineering at the Cooper Union School of Engineering, he received his PhD in Applied Mathematics from Caltech for work on problems in nonlinear diffusion.

His research uses perturbation methods, asymptotics and numerical approaches to study applied questions in fluid dynamics, nonlinear partial differential equations and dynamical systems.

He is the co-Editor-in-Chief of the Journal of Engineering Mathematics and also serves on the editorial boards for the European Journal of Applied Mathematics and Discrete and Continuous Dynamical Series B. He has been an active participant in the Mathematical Problems in Industry (MPI) study group series in the US.

Modeling of magnetic recording devices

The design and dynamics of magnetic recording devices is an area of fundamental importance in computer technology and has led to a long-running series of mathematical modeling problems in industrial study groups.

While some aspects of tape storage, computer hard disk drives and more broadly other micro-electro-mechanical systems (MEMS) can involve complicated electronic control systems, the design and operation of the key components in these devices rests on simple (but sometimes novel) balances of physical effects, making them very amenable to modeling.

Lubrication theory for Low Reynolds number flow can be applied to the study the motion of read/write heads in computer hard disk drives.

The fluid dynamics model describes the interaction of compressible gas flow between the surfaces of the moving disk and the read/write head as they pass very close to each other. Using perturbation methods, this model can be reduced to a nonlinear functional integro-differential equation.

Linear stability analysis and perturbation methods show that the equilibrium solutions include an infinite sequence of Hopf bifurcations yielding co-existing “dangerous” large amplitude periodic orbits. Other recent studies have made use of homogenization theory to describe the influence of patterned hard disk surfaces on the motion of the write head.

Professor Peter Coaldrake

Professor Peter Coaldrake is Vice-Chancellor and CEO of Queensland University of Technology (QUT), a position he took up in April 2003.  Prior, he served for four years as Chair (CEO) of Queensland’s Public Sector Management Commission, the body established by the Goss government to overhaul Queensland’s public sector.

Peter Coaldrake is a dual Fulbright Scholar, as a Postdoctoral Fellow in the field of politics/public policy (1980 – 1981), and as a Senior Scholar in the field of higher education policy and management (2001 – 2002).  Peter Coaldrake became Chair of the Australian Technology Network of Universities (ATN) in February 2013. In May 2011, he completed a two-year term as Chair of the Board of Universities Australia, the peak body of Australia’s universities. He returned as a member of the Board of Universities Australia in May 2014.

In January 2011, he became Chair of the Board of the Organisation for Economic Development – Institutional Management in Higher Education (OECD-IMHE) and was appointed as Chair of the Queensland Heritage Council.  He is also a trustee of the Queensland Museum Foundation. He was appointed by the Premier of Queensland as a Smart State Ambassador in 2006, and was Chair of Queensland’s sesquicentenary celebrations in 2009. Read more about Professor Peter Coaldrake AO