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Record W2024682279 · doi:10.1086/379648

Morphological Analysis of H<scp>i</scp>Features. I. Metric Space Technique

2004· article· en· W2024682279 on OpenAlexaffabout
André Khalil, G. Joncas, Fahima Nekka

Bibliographic record

VenueThe Astrophysical Journal · 2004
Typearticle
Languageen
FieldPhysics and Astronomy
TopicGalaxies: Formation, Evolution, Phenomena
Canadian institutionsUniversité de MontréalUniversité Laval
Fundersnot available
KeywordsPhysicsFractal dimensionGalactic planeFormalism (music)AstrophysicsPixelFractalMetric (unit)GalaxyMathematical analysisMathematicsOptics

Abstract

fetched live from OpenAlex

This is the first of two papers on the morphological analysis of H I features. In this first paper, we use the so-called metric space technique, developed by F. C. Adams and J. Wiseman. The metric space technique is an image analysis, mathematical formalism used to quantitatively compare astrophysical maps according to complexity. Instead of comparing maps on a pixel-by-pixel basis, we compare the maps' one-dimensional "output functions," which characterize specific morphological/physical aspects of the maps. The tool is used to analyze 28 H I features of known origin taken from the Canadian Galactic Plane Survey (CGPS), where the maps are scaled at 18'' per pixel (resolution of 1 cos δ arcmin). Technical and mathematical improvements to the formalism are presented. After classifying the 28 maps according to complexity, we searched for correlations between this complexity ranking and other quantifiable aspects of the H I features such as age, area, H I area, distance, flux from the ionizing star(s), fractal dimension, H I mass, and | z | (the absolute value of the height of the objects, above or below the Galactic plane). The most interesting correlations are (1) the higher the flux of UV photons, the more complex is the photodissociated H I feature, and (2) the older the supernova remnant, the more complex the H I associated with it. There is no correlation between the fractal dimension of the maps and their complexity or their physical characteristics, thus showing that the metric space technique could be used as a solution to the degeneracy of the fractal dimension.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.001
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Simulation or modeling · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.005
Threshold uncertainty score0.011

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.001
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0030.003
Science and technology studies0.0000.001
Scholarly communication0.0010.001
Open science0.0000.001
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0020.000

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.

Opus teacher head0.007
GPT teacher head0.220
Teacher spread0.213 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designSimulation or modeling
Domainnot available
GenreEmpirical

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".

Quick stats

Citations19
Published2004
Admission routes2
Has abstractyes

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