C. Bailey-Kellogg and F. Zhao, "Reasoning about and optimizing distributed parameter physical systems using influence graphs", Proc. QR, 1998. [preprint]

We develop the influence graph mechanism for reasoning about and optimizing decentralized controls for distributed parameter physical systems. Distributed parameter systems, such as air flow around an airplane wing, temperature over a semiconductor wafer, and noise from a photocopy machine, are common physical phenomena. The influence graph mechanism encodes the structural dependency information in a distributed parameter system and exploits the information to (1) alleviate redundant computation and (2) reduce communication and support cooperation among local control processes. Using the mechanism, we obtained a dramatic computational speed-up in optimizing control design for a distributed temperature field.