Preliminary results of a MIMO Harmonic Controller to perform active sound power attenuation with a RHAPSODI
Bibliographic record
Abstract
A Harmonic Acoustic Pneumatic Source (HAPS) is an acoustic device developed to perform active harmonic sound control in turbofans. In order to develop a demonstrator, a ring of multiple HAPS (RHAPSODI) is assembled around a cylindrical duct and a dedicated MIMO harmonic controller was developed to perform active sound power attenuation. The control objective is to develop a MIMO feedback controller adapted to multiple HAPS and using in-duct microphones close to them. Three points are addressed : the control of HAPS as a mechanical modulator, the in-duct error microphones located in the near field of HAPS, and the tuning of the controller. The presented method is based on a dedicated MIMO feedback controller of complex envelops with compensation of near field. The compensation matrix of the near field is tuned during a learning phase based on the measurement of a set of optimal commands experimentally obtained with a dedicated controller using the out-duct microphones. When the matrix of compensation is estimated, the MIMO controller using induct microphones can be used. Preliminary experimental results show that a RHAPSODI of 5 HAPS can attenuate the first harmonic of a radiated tonal sound power by more than 20dB.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".