A Recurrent Neural Network for Detecting Objects in Sequences of Sector-Scan Sonar Images
Bibliographic record
Abstract
This work presents a system for detecting small man-made objects in sequences of sector-scan images formed using a medium-range sector-scan sonar. The detection of such objects is considered out to ranges of 200 m from the vessel and while the vessel is in motion. This paper extends previous work by making use of temporal information present in the data to improve performance. The system begins by cleaning the imagery, which is done by tracking objects on the sea bed in the imagery and using this information to obtain an improved estimate of the motion of the vessel. Once the vessel's motion is accurately known, the imagery is cleaned by temporally averaging the images after motion compensation. The detector consists of two stages. After the first detection stage has identified possible objects of interest, a bank of Kalman filters is used to track objects in the imagery and to supply sequences of feature vectors to the final detection stage. A recurrent neural network is used for the final detection stage. The feedback loops within the recurrent network allow the incorporation of temporal information into the detection process. The performance of the proposed system is shown to exceed the performances of other models for the final detection stage, including nonrecurrent networks that make use of temporal information supplied in the form of temporal feature vectors. The proposed detection system attains a probability of detection of 77.0% at a mean false-alarm rate of 0.4 per image.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.002 |
| 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 | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".