A modified air pycnometer for compost air volume and density determination
Bibliographic record
Abstract
Agnew, J.M., Leonard, J.J., Feddes, J. and Feng, Y. 2003. A modified air pycnometer for compost air volume and density determination. Canadian Biosystems Engineering/Le genie des biosystemes au Canada 45: 6.27-6.35. A method of measuring the bulk density and free air space (FAS) of compost that is quick and accurate, and simulates in situ conditions was required for more efficient management of the composting process. An air pycnometer is a device which uses ideal gas principles to determine the amount of air space within a given material. The modified air pycnometer designed and built to meet the objectives of this work included two 30-L PVC vessels for pressure difference determination and an air cylinder activated piston to simulate the stress conditions found at all pile depths. The FAS and bulk density of manure compost, municipal solid waste compost, and mixtures of biosolids and amendment material (leaves, straw, and woodchips) were measured at various moisture contents and compressive loads. The particle densities of the compost materials were roughly similar (1500-1800 kg/m), and negatively sloped linear bulk density and FAS profiles (variation with depth) were observed for all materials. The linear relationship between bulk density and FAS had an R value of 0.97.
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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 | 0.003 | 0.007 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.006 | 0.004 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.003 | 0.002 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.019 | 0.005 |
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".