(41b) Graph-Based Abstractions and Tools for the Modeling and Simulation of Cyber-Physical Systems
AIChE Annual Meeting
Sunday, November 10, 2019 - 3:51pm to 4:12pm
This talk presents abstractions to model and simulate the dependencies that arise in cyber-physical systems. We discuss an algebraic graph abstraction that captures physical connectivity in complex optimization models and a computing graph abstraction that captures communication connectivity in computing architectures. We will show how the algebraic graph performs as a general decomposition framework for optimization problems and how it facilitates the implementation and interfacing with distributed algorithms such as ADMM , Nested Benders , Lagrangian Decomposition , and Parallel Interior Point methods . We also show how it enables graph partitioning  and community detection capabilities  which can be used to apply decomposition algorithms to complex physical systems that consider computational load balancing aspects .
Finally, we discuss how the computing graph abstraction facilitates the evaluation of optimization and control algorithms and their simulation in virtual environments that involve distributed,
centralized, and hierarchical computing architectures. We discuss its connections with automata theory and discrete event simulation  and how this permits a state-space representation.
We end with an example of simulating a real-time distributed control architecture subject to delays, latency, and communication and controller failures . The proposed abstractions are implemented in a Julia-based software package that we call Plasmo.jl .
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