ArticleSensors (Basel, Switzerland)2021
Information Extraction and Population Estimates of Settlements from Historic Corona Satellite Imagery in the 1960s.
Article in Sensors (Basel, Switzerland), 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
2 citing papers in PubMed, 10 citations in OpenAlex.
- The Applicability of a Complete Archive of Keyhole Imagery for Land-Use Change Detection in China (1960-1984).Sensors (Basel, Switzerland) · 2025Article
- Impacts of road development in sub-Saharan Africa: A call for holistic perspectives in research and policy.iScience · 2025Review
Corrections and comments
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Authors and funding
2 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The Corona satellite program was a historic reconnaissance mission which provided high spatial resolution panchromatic images during the Cold War era. Nevertheless, and despite the historic uniqueness and importance of the dataset, efforts to extract tangible information from this dataset have primarily focused on visual interpretation. More sophisticated approaches have been either hampered or unrealized, often justified by the primitive quality of this early satellite product. In the current study we attempt to showcase the usability of Corona imagery outside the context of visual interpretation. Using a 1968 Corona image acquired over the city municipality of Plovdiv, Bulgaria, we reconstruct a panchromatic 1.8 m spatial resolution georegistered image with a relative displacement Root Mean Square Error (RMSE) of 6.616 (for x dimension) and 1.886 (for y dimension) and employ segmentation and texture analysis to discern agricultural parcels and settlements' footprints. Population statistics of this past era are retrieved from national census and related to settlements' footprints. An exponential relationship between the two variables was identified by applying a semi-log regression. The high adjusted R
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Registered trials
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