With the implementation of smart grids, time of use and real-time pricing is on the horizon of future electricity consumption for commercial and residential uses. This presents a challenge and opportunity for consumers to minimize electricity cost and optimize the demand response profile to take advantage of the timevarying pricing. This talk gives an update on our recent work in using building thermal storage to reduce peak demand energy use while satisfying the user's comfort level. To deal with uncertainties in weather, load factors, and time varying pricing, we employ real time feedback and model predictive control strategy to reduce the peak demand. Control-relevant modeling strategies from real time experimental data will be discussed.
The potency of feedback control is enhanced by using algorithms that combine classical dynamic elements with logic states that facilitate decision-making capabilities. The resulting closed-loop system is a hybrid dynamical system, one in which the overall state changes continuously in some regions of the state space and changes instantaneously at other points. Additional examples of hybrid systems include mechanical systems with impacts and electrical circuits with impulsive behavior. Hybrid dynamical systems have been studied extensively for over twenty years, although until recently little attention has been given to issues related to robustness, a crucial property for engineered hybrid control systems where robustness to modeling errors and measurement noise is paramount. Over the last five years, significant progress has been made for hybrid systems on stability analysis tools and robustness results that parallel what is available for differential and difference equations. In this lecture, some of these tools and results will be described and their impact on control design will be illustrated.
In this colloquium talk, Professor Alexander Balandin overviews some of graphene's properties, and discuss possible applications, focusing on the work conducted at UC-Riverside. Specifically, Balandin talks about the use of Raman spectroscopy as nanometrology tool for graphene; measurements of the lattice (phonon) thermal conductivity of "free" graphene; unique features of the acoustic phonon transport in 2D crystals such as graphene; electron-beam irradiation effects on graphene; design and fabrication of graphene field-effect transistors; and measurements of the electronic 1/f noise in graphene devices. Balandin concludes with my prediction of possible graphene's practical applications.