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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			<text transform="matrix(1,0,0,-1,-71.95,59.63)">
				<tspan style="font-size: 17.93px; " x="0" y="0">ℋ</tspan>
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				<tspan style="font-size: 12.55px; " x="0" y="0">∞</tspan>
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</svg> Optimization

<table>FFT analysis result of <svg height="8.4250002" id="M94" style="vertical-align:-0.273pt" version="1.1" viewbox="0 0 8.5874996 8.4250002" width="8.5874996" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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Advances in Acoustics and Vibration

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Figure 9

Figure 9: 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">
	<g transform="matrix(1.25,0,0,-1.25,0,21.125)">
		<g transform="translate(72,-55.1)">
			<text transform="matrix(1,0,0,-1,-71.95,59.63)">
				<tspan style="font-size: 17.93px; " x="0" y="0">ℋ</tspan>
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</svg> Optimization 

Figure 9 | 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 9

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