Active Noise Cancellation for Ventilation Ducts Using a Pair of Loudspeakers by Sampled-Data <svg style="vertical-align:-4.50008pt;width:37.625px;" id="M1" height="21.125" version="1.1" viewBox="0 0 37.625 21.125" width="37.625"  xmlns="http://www.w3.org/2000/svg">
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</svg> Optimization

<table class="table-group" width="800px"><tr class="fig-image" id="a"><td><img alt="253948.fig.006a" src="https://static.hindawi.com/articles/aav/volume-2008/253948/figures/253948.fig.006a.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(a) </b>Adaptive control</td></tr></table></td></tr><tr class="fig-image" id="b"><td><img alt="253948.fig.006b" src="https://static.hindawi.com/articles/aav/volume-2008/253948/figures/253948.fig.006b.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(b) </b>Robust control</td></tr></table></td></tr></table>

<table>Effect of Swinbanks' source.</table>

Advances in Acoustics and Vibration

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Figure 6

Figure 6: Active Noise Cancellation for Ventilation Ducts Using a Pair of Loudspeakers by Sampled-Data <svg style="vertical-align:-4.50008pt;width:37.625px;" id="M1" height="21.125" version="1.1" viewBox="0 0 37.625 21.125" width="37.625"  xmlns="http://www.w3.org/2000/svg">
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Figure 6 | Active Noise Cancellation for Ventilation Ducts Using a Pair of Loudspeakers by Sampled-Data 
	
		
			
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Advances in Acoustics and Vibration

Active Noise Cancellation for Ventilation Ducts Using a Pair of Loudspeakers by Sampled-Data ℋ ∞ Optimization

Figure 6

Active Noise Cancellation for Ventilation Ducts Using a Pair of Loudspeakers by Sampled-Data Optimization