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Record W2066106458 · doi:10.1029/2009jf001365

Step‐pool stability: Testing the jammed state hypothesis

2010· article· en· W2066106458 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenueJournal of Geophysical Research Atmospheres · 2010
Typearticle
Languageen
FieldEnvironmental Science
TopicHydrology and Sediment Transport Processes
Canadian institutionsUniversity of British ColumbiaBC Hydro (Canada)
Fundersnot available
KeywordsFlumeStability (learning theory)GeologyMechanicsChannel (broadcasting)Geotechnical engineeringEntrainment (biomusicology)Grain sizePhysicsComputer scienceFlow (mathematics)Geomorphology

Abstract

fetched live from OpenAlex

We investigate the stability of step‐pool channels by examining how the traditional approach to bed stability based on the critical Shields number is modified by particles jamming across the width of the channel. Experiments were conducted in a flume with slopes ranging between 3% and 18% and either smooth or rough walls. By varying the size of sediment and width of the flume we observed that the stability of the bed increases as the jamming ratio (channel width/ D 84step is the diameter at which 84% of the step stones are smaller) decreases for jamming ratios less than six. At low jamming ratios both grain‐on‐grain structuring and sediment entrainment phenomena affect the stability of the bed. Actual bed failure, however, depends upon the history of bed development and the chance arrangement of the stone structures in the bed. Thus, the experiments also demonstrate that the inherently stochastic nature of sediment transport affects not only the movement of individual grains but also the stability of the channel as a whole. Since stochastic processes affect the stability of the entire channel, there is no clearly defined separation between stable and unstable beds, rather, an overlapping field where both stable and unstable bed states can exist. This field was modeled using logistic regression to derive a probability of bed failure. A comparison of data from experiments with rough banks and smooth banks showed that rough banks significantly increase the stability of the bed.

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.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.003
metaresearch head score (Gemma)0.002
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.608
Threshold uncertainty score0.997

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0030.002
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.001
Scholarly communication0.0000.000
Open science0.0010.000
Research integrity0.0000.002
Insufficient payload (model declined to judge)0.0040.000

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.

Opus teacher head0.051
GPT teacher head0.294
Teacher spread0.244 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it