I worked during this summer on the modelling and simulation of Hybrid Systems
with Prof. Hans Vangheluwe
in the Modelling, Simulation and Design Lab
(MSDL) of McGill University.
Hybrid Systems (HS) are physical systems which are modelled with continuous
components (Differential Equations) as well as discrete components.
The general goal of this summer (apart the one of giving me experience
in multidisciplinary research) was to investigate which could be the
best formalism to model HS (need expressiveness), and which could
be the best formalism to simulate them (need efficiency). We have chosen
the practical approach of first experimenting with a real Simulator for
Hybrid Systems.
A summary
I had written about my summer researches for an application
to a NSERC postgraduate scholarship
The summer report
for my researches of this summer
(contains links to the new source files for the 522 Simulator)
During the summer 2001, I have worked as a NSERC-funded summer student
with Prof. Prakash Panangaden
on the stability and existence properties of Delay Differential Equations
(DDEs), as well as their numerical solution with
Prof. Hans Vangheluwe .
DDEs are differential equations in which you can relate the derivative
of a function using the value of the function at previous times. For
example, dy/dt(t) = y(t-1) is a DDE with a constant delay of 1. I put here
links to reports I had written at that time. Note that I can't guarantee
the exactness of what is claimed in those reports! They haven't been
peer reviewed; and I have written some hand-written corrections to them
which I have never (not yet?) put on paper. I just put them here
as 'food for thoughts'...