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Record W2484427460 · doi:10.11575/prism/3063

New strategies for combining gnss and photogrammetric data

2009· dissertation· en· W2484427460 on OpenAlex
Cameron Ellum

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenuePRISM (University of Calgary) · 2009
Typedissertation
Languageen
FieldEngineering
TopicSatellite Image Processing and Photogrammetry
Canadian institutionsUniversity of Calgary
Fundersnot available
KeywordsGNSS applicationsPhotogrammetryComputer scienceKalman filterBundle adjustmentKinematicsData processingReal-time computingGeographySystems engineeringComputer visionArtificial intelligenceEngineeringGlobal Positioning SystemTelecommunicationsDatabase

Abstract

fetched live from OpenAlex

The basic concept of integrating GNSS and photogrammetry dates back more than 30 years and for at least the past decade it has been ubiquitous in both aerial and terrestrial mapping. Throughout all its history the basic technique for integrating the two technologies has been the same: GNSS data is post-processed using a Kalman filter yielding positions and these positions are then used as constraining information in a photogrammetric least-squares bundle adjustment. As evidenced by its long and essentially unaltered use the existing strategy works well, nevertheless it has some drawbacks. From a theoretical perspective, the integration is sub-optimal while the information flow is only in the one direction. From an operational perspective, the current approach is unwieldy: (at least) two processing packages are required. The objective of the research contained within this work is to examine new strategies for integrating GNSS and photogrammetric data that alleviate the aforementioned limitations of the current integration strategy. Specifically, two new integration strategies are introduced, implemented, and tested: (1) Inter-processor communication between a kinematic GNSS Kalman filter and a photogrammetric bundle adjustment. (2) A combined least-squares adjustment of both GNSS and photogrammetric observations. The first strategy introduces two-way communication between the GNSS and photogrammetric processors, while the second strategy introduces measurement-level integration within a single processor. The combined adjustment also allows some more flexible GNSS processing options; for instance, a non-fixed base station or the use of observations when there are less than the 4 normally required. Testing of the inter-processor communication strategy showed that it could help GNSS positioning following signal outages, yet this improvement does not necessarily translate into improved photogrammetric mapping accuracy. Testing of the combined adjustment demonstrated how photogrammetric control could replace a fixed GNSS base station, and how use of use of GNSS observations during partial signal blockages (when they would otherwise be discarded) could help bound the mapping and exposure position error growth. The combined adjustment testing also showed that the exposure positions derived from a typical aerial block of imagery have too much noise to substantially improve the GNSS positioning; consequently, mapping accuracy also does not improve.

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.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesMeta-epidemiology (narrow)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Other design · Consensus signal: none
GenreCandidate signal: Methods · Consensus signal: Methods
Teacher disagreement score0.991
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

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

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 head0.019
GPT teacher head0.234
Teacher spread0.215 · 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