(now at 2pm) Applied Maths Seminar: Dressler -- New perspectives on signomial programming with a view toward nonlinear dynamics

Marieke Dressler (The University of New South Wales) will be giving an applied maths
seminar on Wednesday 16th April at **2pm** in **Carslaw 273** (note unusual, changed
time and location to avoid clash with school meeting).  Afterwards, we will go for tea
and Italian biscuits in the tea room.  Students are invited and encouraged to attend to
both.  

Title: New perspectives on signomial programming with a view toward nonlinear dynamics
Abstract: Signomials generalize polynomials by allowing arbitrary real exponents, at the
expense of restricting the resulting function to the positive orthant.  In this talk, I
present a novel convex relaxation hierarchy of lower bounds for signomial optimization
and discuss how it can be used to study nonlinear dynamics.  The hierarchy is derived
through the newly-defined concept of signomial rings and a signomial Positivstellensatz
based on conditional "sums of arithmetic-geometric exponentials" (SAGE).  Numerical
examples are provided to illustrate the performance of the hierarchy on problems in
chemical engineering and optimal control.