Assessment and Design Optimization of Retrofitting Dropshaft with Air Circulation Pipes for Downstream Depressurization
Bibliographic record
Abstract
Plunging flow dropshafts in urban drainage systems have been reported to cause downstream air pressurization and subsequent sewer odor issues. Retrofitting dropshafts with air circulation pipes has been attempted to reduce sewer odour complaints in Edmonton, Alberta, Canada. In the current work, laboratory model study, field monitoring, and model prediction were conducted to assess the effectiveness of this retrofit and explore its design optimization. This retrofitting was found to be effective in reducing air entrainment of the dropshaft and depressurizing the downstream sewers. However, the study showed that horizontal air circulation pipes at various elevations contributed differently in reducing the air entrainment. Based on the air flow model, increasing the size of the horizontal pipes had a more significant effect on reducing the downstream air pressure compared to increasing the number of the pipes. It was found that the retrofitting can be optimized by removing the bottom horizontal air circulation pipes while increasing the pipe size.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot 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.
Codex and Gemma teacher scores by category
| 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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".