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Faculty of Engineering and Information Sciences - Papers: Part A

2006

Theory

Articles 1 - 2 of 2

Full-Text Articles in Social and Behavioral Sciences

A Dual Graph Construction For Higher-Rank Graphs, And K-Theory For Finite 2-Graphs, Stephen Allen, David Pask, Aidan Sims Jan 2006

A Dual Graph Construction For Higher-Rank Graphs, And K-Theory For Finite 2-Graphs, Stephen Allen, David Pask, Aidan Sims

Faculty of Engineering and Information Sciences - Papers: Part A

Given a k-graph Λ and an element p of Nk, we define the dual k-graph, pΛ. We show that when Λ is row-finite and has no sources, the C*-algebras C*(Λ) and C*(pΛ) coincide. We use this isomorphism to apply Robertson and Steger's results to calculate the K-theory of C*(Λ) when Λ is finite and strongly connected and satisfies the aperiodicity condition.


Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi Jan 2006

Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi

Faculty of Engineering and Information Sciences - Papers: Part A

With the entry of Tasmania into the national electricity market, equipment upgrades are required in many parts of the existing power system. This presents an opportunity to embrace new technology, in order to enhance the current efficiency and productivity of the system. One area is that of hydro-turbine speed governors, an integral part of maintaining the frequency of the output. This paper analyses the current standard control algorithm for turbine governors, the PID controller. It illustrates the processes involved, tuning and their limitations. Finally, alternative control systems are discussed.