Moheimani, S. O. RezaPota, Hemanshu R.Petersen, Ian R.2026-07-022026-07-02078034530497807803453000743-1619ORCID:/0000-0003-4856-9450/work/219057250https://hdl.handle.net/1885/733812267This paper presents a new formulation of the acoustic noise and vibration control problem for flexible structures. The problem is formulated as a spatial control problem; e.g., acoustic noise in an entire duct, i.e., distributed over the entire physical space of the duct, should be reduced. In the paper it is shown that for certain configurations it is possible to solve this spatial control problem by reducing it to the standard LQG or the H∞ problem.5en199810.1109/ACC.1998.7031060342637454