Permittivity Measurements of High Conductivity Specimens using an Open-Ended Coaxial Probe—Measurement Limitations
Bibliographic record
Abstract
Non-destructive electromagnetic wave-based techniques have been used for over a century to gain insight into the behaviour of geomaterials. The technique used in this study is a high frequency (20MHzto1.3GHz) open-ended coaxial probe measurement system. This study highlights the importance of knowing the limitations of the measurement system. The specimens that are tested are aqueous solutions of NaCl, CaCl2, and FeCl3 with conductivities ranging from approximately 10−3to8S∕m. Real permittivity data of the high conductivity specimens show a relaxation phenomena at MHz frequencies where none exists, indicating that electrode polarization is occurring. The frequency at which electrode polarization begins to manifest (e.g., limiting frequency) increases as the specimen conductivity increases. An empirical relationship between the limiting frequency and specimen conductivity is presented and is applied to three kaolinite-NaCl slurries. Additional problems associated with measuring high conductivity specimens using this equipment may arise since the model for the aperture admittance was optimized using low conductivity materials. Previous studies have shown that measurement errors at low frequencies are reduced if the system is calibrated using a material of similar electrical properties to the test specimen.
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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 | 0.003 | 0.013 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.001 | 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".