An inductively coupled passive tag for remote basic volatile sensing
Bibliographic record
Abstract
We present a passive tag capable of detecting basic volatiles in the surrounding environment. The tag is based on a voltage dependant frequency shift approach using a LC resonator comprised of a spiral inductor in parallel with a varactor. The volatile detector, comprised of a pair of pH-sensitive electrodes coated with a very thin layer of hydrogel, is connected in parallel with the varactor. The hydrogel is utilized as an absorptive medium for the basic volatiles and acts to contain the electrolyte. Due to the absorption of the basic volatile, the hydrogel pH changes which in turn changes the voltage across the pH-sensitive electrode pair shifting the resonant frequency of the tag. An interrogator coil is inductively coupled to the tag inductor to remotely track the resonant frequency of tag at distances ranging from 5 to 11 cm. Tests with ammonia show that the tag has a detection limit of 1.5 ppm. With less than a 20 min response time, the tag has potential for application in food freshness monitoring where detecting basic volatiles is important.
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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) | 0.001 | 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 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".