Bed form initiation from a flat sand bed
Bibliographic record
Abstract
Bed form initiation in unidirectional flow is examined on a flat bed composed of a homogeneous 0.5 mm sand. Velocity profiles taken prior to bed form development indicate that the examined flows are typical of fully turbulent, uniform, open channel flows. Under these conditions, two separate modes of bed form initiation are observed: defect and instantaneous initiation. Defect initiation occurs at lower flow stages, where sediment transport is sporadic and patchy, and is characterized by defect propagation associated with flow separation. Instantaneous initiation occurs at larger flow strengths, where sediment transport is general and widespread. This form of bed form initiation begins with the imprinting of a cross‐hatch pattern on the flat sediment bed, which leads to chevron‐shaped forms that migrate independently of the initial pattern. The chevrons eventually align to form incipient crest lines. This mode of bed form initiation does not appear to be linked to turbulent structures, but integral scales derived from velocity measurements prior to bed form development are similar to the initial bed form length scales.
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 | 0.000 | 0.000 |
| 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 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 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".