Echo sounding with the shock wave generated by the implosion of an instrument pressure housing
Bibliographic record
Abstract
In December 2014, what was intended to be a passive-acoustic experiment at the Challenger Deep, suddenly became an active-acoustic experiment. Two free-falling, passive-acoustic instrument platforms, each with a suite of hydrophones, a CTD, a sound speed sensor and a glass-sphere pressure housing containing the electronics, were deployed from the R/V Falkor. One of the platforms imploded at a nominal depth of 9000 m. The highly energetic, broadband shock wave created by the implosion was recorded by the surviving platform. The shock wave reflected multiple times from the seafloor and the surface and the arrival times of the multiple reflections were used to obtain a highly constrained estimate of the Challenger Deep: 10 983 ± 6 m. We will discuss the signal processing methods used and propagated uncertainty in this highly constrained estimate. We will also discuss how this estimate of the depth of the deepest part of the ocean compares with other estimates of the depth of the Challenger Deep, including an update on estimates obtained following the publication of this study.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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".