An Unpowered Sensor Node for Real-Time Water Quality Assessment (Humic Acid Detection)
Bibliographic record
Abstract
A zero-power microwave sensor is reported for the real-time assessment of water quality. The proposed structure is able to transmit sensed data directly to a base-station without additional data processing at the wireless sensor node (WSN) which results in less power consumption. The base-station propagates a single tone signal at the frequency of f0/2. At the sensing node, an antenna absorbs that signal and a passive frequency doubler makes its frequency twice, i.e., f0, which will be used as the carrier signal. Two pairs of open-ended coaxial probes are used as liquid sensors; one inside a known reference sample and the other one inside the water under test. A combination of both sensors’ data will be sent to the base-station. A special six-port structure is used for modulation of sensed data over the carrier. At the base-station, a receiver will demodulate the received signal for extracting the sensed data. As an example, the system has been evaluated at f0 = 2.45 GHz for the detection of Humic-Acid levels as a common contaminant of river waters.
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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 | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".