Past Industrial and Interdisciplinary Workshops

14 May 2010
11:45
to
13:00
Andrew Stewart and Trevor Wood
Abstract
Andrew Stewart - The role of the complete Coriolis force in ocean currents that cross the equator Large scale motions in the atmosphere and ocean are dominated by the Coriolis force due to the Earth's rotation. This tends to prevent fluid crossing the equator from one hemisphere to the other. We investigate the flow of a deep ocean current, the Antarctic Bottom Water, across the equator using a shallow water model that includes the Earth's complete Coriolis force. By contrast, most theoretical models of the atmosphere and ocean use the so-called traditional approximation that neglects the component of the Coriolis force associated with the locally horizontal component of the Earth's rotation vector. Using a combination of analytical and numerical techniques, we show that the cross-equatorial transport of the Antarctic Bottom Water may be substantially influenced by the interaction of the complete Coriolis force with bottom topography.
  • Industrial and Interdisciplinary Workshops
12 March 2010
11:30
to
13:00
Various
Abstract
• Amy Smith presents: “Multiscale modelling of coronary blood flow derived from the microstructure” • Laura Gallimore presents: “Modelling Cell Motility” • Jean-Charles Seguis presents: “Coupling the membrane with the cytosol: a first encounter”
  • Industrial and Interdisciplinary Workshops
12 March 2010
10:00
to
11:15
Lenny Smith, Dan Rowlands, Tim Palmer, Chris Farmer et al.
Abstract
This will not be a normal workshop with a single scientist presenting an unsolved problem where mathematics may help. Instead it is more of a discussion meeting with a few speakers all interested in a single theme. So far we have: Lenny Smith (LSE) on Using Empirically Inadequate Models to inform Your Subjective Probabilities: How might Solvency II inform climate change decisions? Dan Rowlands (AOPP, Oxford) on "objective" climate forecasting; Tim Palmer (ECMWF and AOPP, Oxford) on Constraining predictions of climate change using methods of data assimilation; Chris Farmer (Oxford) about the problem of how to ascertain the error in the equations of a model when in the midst of probabilistic forecasting and prediction.
  • Industrial and Interdisciplinary Workshops
5 March 2010
10:00
to
13:00
Ralph Brownie and Andy Stove
Abstract
Synthetic Aperture Radars (SARs) produce high resolution images over large areas at high data rates. An aircraft flying at 100m/s can easily image an area at a rate of 1square kilometre per second at a resolution of 0.3x0.3m, i.e. 10Mpixels/sec with a dynamic range of 60-80dB (10-13bits). Unlike optical images, the SAR image is also coherent and this coherence can be used to detect changes in the terrain from one image to another, for example to detect the distortions in the ground surface which precede volcanic eruptions. It is clearly very desirable to be able to compress these images before they are relayed from one place to another, most particularly down to the ground from the aircraft in which they are gathered. Conventional image compression techniques superficially work well with SAR images, for example JPEG 2000 was created for the compression of traditional photographic images and optimised on that basis. However there is conventional wisdom that SAR data is generally much less correlated in nature and therefore unlikely to achieve the same compression ratios using the same coding schemes unless significant information is lost. Features which typically need to be preserved in SAR images are: o texture to identify different types of terrain o boundaries between different types of terrain o anomalies, such as military vehicles in the middle of a field, which may be of tactical importance and o the fine details of the pixels on a military target so that it might be recognised. The talk will describe how Synthetic Aperture Radar images are formed and the features of them which make the requirements for compression algorithms different from electro-optical images and the properties of wavelets which may make them appropriate for addressing this problem. It will also discuss what is currently known about the compression of radar images in general.
  • Industrial and Interdisciplinary Workshops
26 February 2010
10:00
to
11:15
Jorn Dunkel
Abstract
Micron-sized bacteria or algae operate at very small Reynolds numbers. In this regime, inertial effects are negligible and, hence, efficient swimming strategies have to be different from those employed by fish or bigger animals. Mathematically, this means that, in order to achieve locomotion, the swimming stroke of a microorganism must break the time-reversal symmetry of the Stokes equations. Large ensembles of bacteria or algae can exhibit rich collective dynamics (e.g., complex turbulent patterns, such as vortices or spirals), resulting from a combination of physical and chemical interactions. The spatial extent of these structures typically exceeds the size of a single organism by several orders of magnitude. One of our current projects in the Soft and Biological Matter Group aims at understanding how the collective macroscopic behavior of swimming microorganisms is related to their microscopic properties. I am going to outline theoretical and computational approaches, and would like to discuss technical challenges that arise when one tries to derive continuum equations for these systems from microscopic or mesoscopic models.
  • Industrial and Interdisciplinary Workshops

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