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Record W2982268990 · doi:10.4095/288043

Light-weight coring in permafrost at GSC - current activities

2011· report· en· W2982268990 on OpenAlexaff
W E Sladen

Bibliographic record

Venuenot available
Typereport
Languageen
FieldEarth and Planetary Sciences
TopicClimate change and permafrost
Canadian institutionsNatural Resources Canada
Fundersnot available
KeywordsCoringPermafrostCurrent (fluid)GeologyPhysical geographyGeographyOceanographyEngineeringDrilling

Abstract

fetched live from OpenAlex

Light-weight coring techniques used by the GSC in recent years include coring with a modified Cold Regions Research and Engineering Laboratory (CRREL) barrel and a diamond impregnated bit barrel. The modified CRREL barrel is a hollow mild steel barrel with welded double helix flight configuration. The removable shoe has replaceable tungsten carbide teeth which do the cutting. Attached to a power head, the CRREL barrel can retrieve a high-quality, continuous core in snow, ice, and fine-grained organic and mineral soils. The disadvantage of the CRREL barrel is that is does not work well in stony ground, unfrozen soils or soils with a significant unfrozen water content. In addition, the drilling process can be slow due to insufficient storage for the cuttings on the outside of the barrel limiting the length of core recoverable in a single run. A second method used by the GSC is diamond drilling, which uses a core barrel with a diamond impregnated carbide bit. Also attached to a power head, this method can cut through fine-grained soil with ice, sand, gravel, and boulders up to 20 cm in diameter. This off the shelf equipment produces a high quality continuous core. The disadvantages are that in pure ice the core tends to break into smaller segments, slowing drilling, and in warmer permafrost conditions (-2 to 0ºC) the core tends to disintegrate due to the uncemented material and frictional heat. Both methods are applicable in a wide range of terrain types, they are light-weight and easily transportable by snow machine, ATV trailer and helicopter.

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 imitation

Not 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.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.001
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.980
Threshold uncertainty score0.041

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.001
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0020.002
Science and technology studies0.0010.000
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0060.002

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 head0.110
GPT teacher head0.287
Teacher spread0.176 · 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

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

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".

Quick stats

Citations0
Published2011
Admission routes1
Has abstractyes

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