New students!

This is a shameless plug for UCAS admissions the Engineering Mathematics Department at Bristol — I am the new admissions tutor after all…

If you are interested in studying mathematics and want to learn how it can be used for real-world problem solving then you should check out the Engineering Mathematics integrated Masters (MEng) and Bachelors (BEng) programmes. We’re quite unlike traditional mathematics courses in that we don’t teach mathematics for the sake of it but we focus on the skills you need to work in high tech industries such as Engineering and the Bio-sciences. That said, we don’t short change you on the mathematics — if you are going to be a problem solver you are going to need abilities that come from studying high calibre mathematics to get the job done!

Oh, and if you are looking for postgraduate studies (that is, a PhD) rather than undergraduate, please see my page for prospective students.

PS: Bristol is a great city to be in!

Systematic experimental exploration of bifurcations with noninvasive control

One of the things I’ll be doing on this new website is highlighting some of my papers, past and present. This paper is one I’m particularly pleased with as it showcases what you can do when you link numerical methods (computer algorithms) with a physical experiment in real-time.

Normally to investigate the behaviour of a system or structure (e.g., an aerofoil) you would build a mathematical model of the system, then validate it (hopefully! lots of people skip this step) and then investigate it using some of the sophisticated mathematical tools we have for analysis. This paper looks at how we can throw out the model building step and use those same sophisticated mathematical tools directly on the original physical experiment. OK, there are a few constraints (we must have quite a bit of control over the experiment) but it does mean that we can be sure that the behaviour we see is real and not just because the model is wrong.

This paper looks at a very simple physical example, namely an energy harvester but it demonstrates the principle nicely.

Reference: Systematic experimental exploration of bifurcations with noninvasive control, David A.W. Barton and Jan Sieber, Physical Review E 87 2013, 052916. DOI: 10.1103/PhysRevE.87.052916. Preprint (open access): arXiv 1209.3713.

New website!

At long last I’ve got around to updating this website! Over the next few weeks and months I hope to fully refresh the content in here to fully reflect some of the things I’m doing at the moment.

Some of the things that have been keeping me particularly busy are my new role as admissions officer for all undergraduate admissions to the Department of Engineering Mathematics and also all the things I’m responsible for at Emmanuel Bishopston (part of the Emmanuel Bristol family of churches).

You’ll notice a lot more images on this website now; a lot of them are from morgueFile — a great resource if you ever need free (that is, public domain, free to reuse however you want) images.

Installing QNX on Fedora

It turns out that installing QNX on Fedora isn’t that easy unless you know how… Firstly, QNX is a 32bit program and requires the following packages to be installed on Fedora if you don’t already have them (e.g., you are running a 64 bit system).

For the installer

  • glibc.i686
  • libXp.i686
  • gtk2.i686

For qde

  • libXmu.i686
  • libXtst.i686

Then you have to work out why the QNX installer says that “A suitable JVM could not be found.”

It turns out that the QNX installer is searching for a specific version of the Java JRE (which for QNX  6.5.0 is Sun Java v1.5, though it doesn’t seem to care which update version).

The only way to find this out is to make use of the log function of the installer. Running the installer with “-is:log log.txt” will create a log file called log.txt and in there you’ll find a line which tells you the version that QNX is looking for; for me it was “Sun Microsystems Java Runtime Environment (JRE) 1.5 for Linux”. You then need to download the appropriate Java package from Oracle (the current owners of Java) or elsewhere.

Edit: it turns out that under Linux, installing service pack 1 deletes some necessary files. To fix this you must specify “-console” on the installation command line like below. (This forces QNX to use the command line based installer which works correctly unlike the graphical one…)

Once downloaded and unpacked, simply set the QNX_JAVAHOME environment variable to the correct path and run the installer. (You don’t need to permanently install the JRE since QNX installs it’s own version; it’s only needed for the installer.) The command line for me was “sudo -E QNX_JAVAHOME=/tmp/jre1.5.0_22/ ./qnxsdp-6.5.0SP1-201206271006-linux.bin – console”.

Once the base QNX package is installed, you can install service pack 1 on top. This time QNX needs to use the Java installation that it just installed alongside itself. For me this meant that I didn’t need to specify the Java path for the service pack. Again, the command line for me was “sudo -E ./qnxsdp-6.5.0SP1-201206271006-linux.bin -console”.

Once all that is done (and you’ve activated the software), it should all work!