A look at reverberation received on a vertical array during the TREX13 experiment
Bibliographic record
Abstract
The TREX13 Target and Reverberation Experiment was conducted in shallow water off Panama City, Florida. Previously published work focused on reverberation from a fixed horizontal array, which resolves scattering in the azimuthal direction, but has very limited information about the vertical dependence of the scattering. Here, we look at the TREX13 datai—LFM pulses of various bandwidths in the 1.8–3.6 kHz frequency range—received on the vertical line arrays (VLAs) to see what information can be gleaned. The depth and time dependence of the reverberation and echo from a target are investigated. Beams are formed at various vertical angles, which should provide information about the grazing angle dependence of the scattering. A complication arises in determining the scattering strength in non-uniform environments, since the reverberation comes from all azimuths, and since the source and vertical array receivers were not co-located. In such bistatic geometry, the energy arriving at any instant comes from different ranges, azimuths, and vertical angles. However, if the source and receiver are close together, at longer times the geometry approximates the simpler monostatic situation. To help interpretation, results are compared with predictions from a range-dependent bistatic reverberation model. [Work supported by ONR, Ocean Acoustics.]
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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 | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
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".