| Autor: |
K. R. Cook, G. J. Hanson, W. Hahn |
| Rok vydání: |
2002 |
| Předmět: |
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| Zdroj: |
Applied Engineering in Agriculture. 18 |
| ISSN: |
1943-7838 |
| DOI: |
10.13031/2013.11312 |
| Popis: |
Two– and three – dimensional analysis using close–range digital photographs can be very useful in measuring changes in erosion on the landscape. Computer software exists for conducting photographic analysis but it is often either cost prohibitive or very labor intensive to use. This article describes a simple 2–D image–based technique used to conduct simple measurements photographically using software that would typically already be in use in an engineering office (i.e. CAD, image editing, and spreadsheet programs). The technique is very repeatable and results in reliable measurements when compared to actual physical measurements. The accuracy of using these measurements was evaluated by comparing physically measured distances and photographically measured distances between parallel ropes on the landscape. The standard error was 17 mm with a coefficient of determination of 1.0 for the linear regression. The overall mean absolute deviation of residuals was 18 mm and the maximum absolute residual was 52 mm. The application selected for this article is the documentation of the extent and width of erosion during an embankment–overtopping test. This technique was demonstrated to be an effective method for measuring distances and locations on the landscape. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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