Bibliographic record
Abstract
Abstract Exergy analysis is used to evaluate the efficiency of a turbojet engine over an entire flight (including climb, cruise and descent), and to assess the sensitivity of these results to the selection of the reference environment. This study is an extension of previous work where the accuracy of an exergy analysis of a turbojet engine is evaluated for different reference environments on an instantaneous basis. The present work evaluates cumulative engine efficiencies. The results show that the use of a constant reference environment set at cruise altitude conditions yields cumulative exergy efficiencies that are within 0.01% of those found using a variable reference environment (equal to the operating environment conditions at all times) over a 3,500 km flight. This result is in contrast to the use of a constant sea-level reference environment where such are 3.7%. This significant cumulative efficiency difference with the choice of reference environment is not observed when using an instantaneous exergy analysis. Care must be exercised when using a constant reference environment, as for both constant sea-level and cruise-altitude reference environments cumulative rational efficiencies increase over the majority of the flight, whereas for a continuously varying reference environment these efficiencies decrease.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| 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".