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Full-Text Articles in Earth Sciences
Accuracy Of Unmanned Aerial System (Drone) Height Measurements, Daniel R. Unger, I-Kuai Hung, David L. Kulhavy, Yanli Zhang, Kai Busch-Petersen
Accuracy Of Unmanned Aerial System (Drone) Height Measurements, Daniel R. Unger, I-Kuai Hung, David L. Kulhavy, Yanli Zhang, Kai Busch-Petersen
International Journal of Geospatial and Environmental Research
Vertical height estimates of earth surface features using an Unmanned Aerial System (UAS) are important in natural resource management quantitative assessments. An important research question concerns both the accuracy and precision of vertical height estimates acquired with a UAS and to determine if it is necessary to land a UAS between individual height measurements or if GPS derived height versus barometric pressure derived height while using a DJI Phantom 3 would affect height accuracy and precision. To examine this question, height along a telescopic height pole on the campus of Stephen F. Austin State University (SFASU) were estimated at 2, …
Accuracy Assessment Of Pictometry® Height Measurements Stratified By Cardinal Direction And Image Magnification Factor, Daniel Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang
Accuracy Assessment Of Pictometry® Height Measurements Stratified By Cardinal Direction And Image Magnification Factor, Daniel Unger, David Kulhavy, I-Kuai Hung, Yanli Zhang
International Journal of Geospatial and Environmental Research
The aim of this project was to ascertain if Pictometry® estimated height could be used in lieu of field-based height estimation. Height of a light pole measured with a telescopic height pole was compared to Pictometry® hyperspatial 4-inch (10.2 centimeters) multispectral imagery estimated light pole height on the campus of Stephen F. Austin State University, Nacogdoches, Texas. Average percent agreement between light pole height and Pictometry® estimated light pole height summarized by Pictometry® image magnification factors at 100%, 125%, 150%, 200%, and 300% magnification were within 98% of light pole height with percent disagreement ranging from …
Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David L. Kulhavy, Daniel R. Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung
Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David L. Kulhavy, Daniel R. Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung
International Journal of Geospatial and Environmental Research
Slope distance was measured between the top of 30 light poles and their respective ground level coordinate identified within a central parking lot on the campus of Stephen F. Austin State University, Nacogdoches, Texas. Slope distance measured using Pictometry® hyperspatial 4-inch (10.2 centimeters) multispectral imagery within a web based interface was compared to in situ total station and tape measured slope distance. The range for mean slope distance for Pictometry®, total station, and tape measured slope distance was 0.05 meters. Mean slope distance was 15.36 meters, 15.37 meters, and 15.41 meters for Pictometry®, total station, …