Transitory echoes and critical frequencies - their role in decoding the ionosphere over London
Bibliographic record
Abstract
In 1901, that Marconi was able to claim he had successfully transmitted a radio signal from Cornwall to Newfoundland, a distance of around 3500 km. The successful reception of Morse code signals from the transmitter at Poldhu in Cornwall raised two puzzling anomalies. Firstly, the path followed by the radio waves appeared to contradict the notion that such waves should only travel in straight lines, and secondly that there appeared to be a considerable discrepancy between the transmission distances that could be achieved as darkness fell-typically 1120 km by day and up to 2500 km at night These two pivotal factors were the precursors which led to the discovery of a plasma surrounding the Earth, much of the early research in the subject being carried out using the region of the ionic reflecting layer over north-west London. This paper discusses the work by Edward Appleton on investigation of a reflecting layer in the upper atmosphere. Working from his laboratory in the Strand, Appleton and his team systematically investigated the reflecting properties of the ionosphere using pulses of varying frequency. During the winter months of 1926-27 he conducted soundings of the ionosphere which produced somewhat puzzling transient multiple echoes, and his subsequent discovery of critical frequencies allowed him to show that the ionosphere was a series of separate reflecting regions, with varying electron densities which were affected by the intensity of incident ultra violet radiation. (6 pages)
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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 | 0.002 |
| 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 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.000 | 0.001 |
| 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".