Canadian Acoustics I Acoustique Canadienne 18(2)25-31 (1990) THREE DIMENSIONAL ACTIVE NOISE CANCELLATION USING SPHERICAL ARRAYS OF CARDIOID SOURCES
Bibliographic record
Abstract
Computer modelling is used to design a two element loudspeaker sys tem ('tripole') capable of generating an accurate cardioid radiation pattern for frequencies below 500 Hz. The model is used to assess the effectiveness of various spherical arrays of such tripoles at cancelling a spherical sound field. One cancelling tripole array is built and found to behave in accordance with the model predictions. SOMMAIRE La modélisation par ordinateur est employe dans le concept d 'un systeme (tripoles) a deux elements capabale de generer un profil car-dioide precis de radiation pour des frequences inférieures a 500 Hz. Le modele est employe pour evaluer l'efficacite des étalagés spheriques de telles tripoles afin de reduire le champs spheriques de sonorité. Un étalagé tripoles d'annulation est construit et il est trouve que son comportement suit le modele de prediction.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.063 | 0.015 |
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 source (direct Gemma or distilled Codex), 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".