초록 ▼

A method is provided for making localized decisions and taking localized actions to achieve a global solution. In an embodiment of the present invention, acoustic impedances for impedance-tunable acoustic segments are adjusted. A first acoustic segment through an N-th acoustic segment are defined. T

A method is provided for making localized decisions and taking localized actions to achieve a global solution. In an embodiment of the present invention, acoustic impedances for impedance-tunable acoustic segments are adjusted. A first acoustic segment through an N-th acoustic segment are defined. To start the process, the first acoustic segment is designated as a leader and a noise-reducing impedance is determined therefor. This is accomplished using (i) one or more metrics associated with the acoustic wave at the leader, and (ii) the metric(s) associated with the acoustic wave at the N-th acoustic segment. The leader, the N-th acoustic segment, and each of the acoustic segments exclusive of the leader and the N-th acoustic segment, are tuned to the noise-reducing impedance. The current leader is then excluded from subsequent processing steps. The designation of leader is then given one of the remaining acoustic segments, and the process is repeated for each of the acoustic segments through an (N−1)-th one of the acoustic segments.

대표청구항 ▼

1. A method of adjusting acoustic impedances for impedance-tunable acoustic segments, comprising the steps of: providing a plurality of impedance-tunable acoustic segments for exposure to an acoustic wave wherein a first acoustic segment through an N-th acoustic segment are defined;designating said

1. A method of adjusting acoustic impedances for impedance-tunable acoustic segments, comprising the steps of: providing a plurality of impedance-tunable acoustic segments for exposure to an acoustic wave wherein a first acoustic segment through an N-th acoustic segment are defined;designating said first acoustic segment as a leader;determining a noise-reducing impedance for said acoustic segment so-designated as said leader using (i) at least one metric associated with said acoustic wave at said leader, and (ii) said at least one metric associated with said acoustic wave at said N-th acoustic segment;tuning said leader, said N-th acoustic segment, and remaining ones of said acoustic segments exclusive of said leader and said N-th acoustic segment, to said noise-reducing impedance so-determined;excluding said leader so-tuned from subsequent steps in said method;re-designating one of said remaining ones of said acoustic segments to be said leader; andrepeating said steps of determining, tuning, excluding, and re-designating, for each of said acoustic segments through an (N−1)-th one of said acoustic segments. 2. A method according to claim 1, wherein said step of determining is accomplished using a wireless sensor and actuator node at each of said leader and said N-th acoustic segment. 3. A method according to claim 1, wherein each of said acoustic segments includes adaptive resonators, and wherein said step of tuning comprises the step of changing at least one of resistance and reactance of said adaptive resonators. 4. A method according to claim 1, wherein said acoustic segments are arranged inside a duct. 5. A method according to claim 3, wherein said acoustic segments are arranged inside a duct. 6. A method according to claim 1, wherein said acoustic segments are arranged inside an engine nacelle. 7. A method according to claim 3, wherein said acoustic segments are arranged inside an engine nacelle. 8. A method according to claim 1, further comprising the step of continuously monitoring change in said acoustic wave at said first acoustic segment wherein, when said change exceeds a threshold, said method repeats said steps of designating, determining, tuning, excluding, re-designating, and repeating. 9. A method according to claim 1, wherein said step of determining is carried out at said leader. 10. A method according to claim 1, wherein said step of determining includes the step of wirelessly transmitting said at least one metric associated with said acoustic wave at said N-th acoustic segment to said leader. 11. A method according to claim 1, wherein said step of tuning includes the step of wirelessly transmitting said noise-reducing impedance so-determined from said leader to said N-th acoustic segment and each of said remaining ones of said acoustic segments. 12. A method of adjusting acoustic impedances for impedance-tunable acoustic segments, comprising the steps of: providing a plurality of impedance-tunable acoustic segments arrayed serially in a direction of an acoustic wave that propagates therealong wherein a first acoustic segment through an N-th acoustic segment are defined relative to said direction;designating said first acoustic segment as a leader;determining a noise-reducing impedance for said acoustic segment so-designated as said leader using (i) at least one metric associated with said acoustic wave at said leader, and (ii) said at least one metric associated with said acoustic wave at said N-th acoustic segment;tuning said leader, said N-th acoustic segment, and each of said acoustic segments between said leader and said N-th acoustic segment, to said noise-reducing impedance so-determined;re-designating said leader to be a next successive one of said acoustic segments relative to said direction; andrepeating said steps of determining, tuning, and re-designating, for each of said acoustic segments through an (N−1)-th one of said acoustic se rents. 13. A method according to claim 12, wherein said step of determining is accomplished using a wireless sensor and actuator node at each of said leader and said N-th acoustic segment. 14. A method according to claim 12, wherein each of said acoustic segments includes adaptive resonators, and wherein said step of tuning comprises the step of changing at least one of resistance and reactance of said adaptive resonators. 15. A method according to claim 12, wherein said acoustic segments are arrayed along the inside of a duct. 16. A method according to claim 14, wherein said acoustic segments are arrayed along the inside of a duct. 17. A method according to claim 12, wherein said acoustic segments are arrayed along the inside of an engine nacelle. 18. A method according to claim 14, wherein said acoustic segments are arrayed along the inside of an engine nacelle. 19. A method according to claim 12, further comprising the step of continuously monitoring change in said acoustic wave at said first acoustic segment wherein, when said change exceeds a threshold, said method repeats said steps of designating, determining, tuning, re-designating, and repeating. 20. A method according to claim 12, wherein said step of determining is carried out at said leader. 21. A method according to claim 12, wherein said step of determining includes the step of wirelessly transmitting said at least one metric associated with said acoustic wave at said N-th acoustic segment to said leader. 22. A method according to claim 12, wherein said step of tuning includes the step of wirelessly transmitting said noise-reducing impedance so-determined from said leader to said N-th acoustic segment and each of said acoustic segments between said leader and said N-th acoustic segment. 23. A method of adjusting acoustic impedances for impedance-tunable acoustic segments, comprising the steps of: providing a plurality of impedance-tunable acoustic segments arrayed serially in a direction of an acoustic wave that propagates therealong wherein a first acoustic segment through an N-th acoustic segment are defined relative to said direction;designating said first acoustic segment as a leader;determining, at said leader, a noise-reducing impedance for said acoustic segment so-designated as said leader using (i) at least one metric associated with said acoustic wave at said leader, and (ii) said at least one metric associated with said acoustic wave at said N-th acoustic segment;wirelessly transmitting said noise-reducing impedance so-determined from said leader to said N-th acoustic segment and each of said acoustic segments between said leader and said N-th acoustic segment;tuning said leader, said N-th acoustic segment, and each of said acoustic segments between said leader and said N-th acoustic segment, to said noise-reducing impedance so-determined;re-designating said leader to be a next successive one of said acoustic segments relative to said direction; andrepeating said steps of determining, wirelessly transmitting, tuning, and re-designating, for each of said acoustic segments through an (N−1)-th one of said acoustic segments. 24. A method according to claim 23, wherein said step of determining is accomplished using a wireless sensor and actuator node at each of said leader and said N-th acoustic segment. 25. A method according to claim 23, wherein each of said acoustic segments includes adaptive resonators, and wherein said step of tuning comprises the step of changing at least one of resistance and reactance of said adaptive resonators. 26. A method according to claim 23, wherein said acoustic segments are arrayed along the inside of a duct. 27. A method according to claim 25, wherein said acoustic segments are arrayed along the inside of a duct. 28. A method according to claim 23, wherein said acoustic segments are arrayed along the inside of an engine nacelle. 29. A method according to claim 25, wherein said acoustic segments are arrayed along the inside of an engine nacelle. 30. A method according to claim 23, further comprising the step of continuously monitoring change in said acoustic wave at said first acoustic segment wherein, when said change exceeds a threshold, said method repeats said steps of designating, determining, wirelessly transmitting, tuning, re-designating, and repeating. 31. A method according to claim 23, wherein said step of determining includes the step of wirelessly transmitting said at least one metric associated with said acoustic wave at said N-th acoustic segment to said leader.