Feedforward/Feedback control of HCCI combustion timing
Bibliographic record
Abstract
Homogeneous Charge Compression Ignition (HCCI) engines have the advantage of low Nitrogen Oxides (NO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> ) and soot emissions. In HCCI engines, a lean premixed air-fuel mixture is compressed until the temperature is high enough for combustion to occur. HCCI engines have a limited operating range and are limited by knock at high loads and misfire at low loads. They are without a direct source to initiate ignition so HCCI requires combustion timing control. Some of the factors that affect HCCI combustion timing are mixture composition, pressure and temperature at the time of inlet valve closing. One effective way to control HCCI combustion timing is Variable Valve Timing (VVT). VVT changes the amount of trapped residual gas and the effective compression ratio. These factors have a strong effect on HCCI combustion timing. One main advantage of VVT is that it is fast enough to handle rapid transients. Based on a simplified control oriented model that models the effect of trapped residual gas on combustion timing, a Feedforward/Feedback controller is designed for HCCI combustion timing control. The controller requires feedforward information of the valve timing and feedback information of the combustion timing. This controller tracks the desired combustion timing trajectory both in simulation and experiment by modulating the trapped residual gas using VVT actuation.
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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 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".