Open Access. Powered by Scholars. Published by Universities.®
Social and Behavioral Sciences Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Publication
Articles 1 - 7 of 7
Full-Text Articles in Social and Behavioral Sciences
Accuracy Of Unmanned Aerial System (Drone) Height Measurements, Daniel Unger, I-Kuai Hung, David Kulhavy, Yanli Zhang, Kai Busch-Peterson
Accuracy Of Unmanned Aerial System (Drone) Height Measurements, Daniel Unger, I-Kuai Hung, David Kulhavy, Yanli Zhang, Kai Busch-Peterson
Faculty Publications
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, …
Evidence For Deviations From Uniform Changes In A Portuguese Watershed Illustrated By Corine Maps: An Intensity Analysis Approach, Zara Teixeira, João C. Marques, Robert Gilmore Pontius
Evidence For Deviations From Uniform Changes In A Portuguese Watershed Illustrated By Corine Maps: An Intensity Analysis Approach, Zara Teixeira, João C. Marques, Robert Gilmore Pontius
Geography
We apply a method to evaluate the strength of the evidence for deviations from uniform land change in a coastal area, in the context of Intensity Analysis. The errors in the CORINE maps at 1990 and 2006 can influence the apparent change, but the errors are unknown because error assessment of the 1990 map has never been released, while the error of the 2006 map has been checked for only some countries. The 1990 and the 2006 maps of a coastal watershed in Portugal served as the data to compute the intensities of changes among eight categories. We evaluate the …
Comparing Remotely Sensed Pictometry® Web Based Slope Distance Estimates With In Situ Total Station And Tape Slope Distance Estimates, David Kulhavy, Daniel 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 Kulhavy, Daniel Unger, Yanli Zhang, Phillip Bedford, I-Kuai Hung
Faculty Publications
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, …
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
Faculty Publications
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 …
A Suite Of Tools For Roc Analysis Of Spatial Models, Jean François Mas, Britaldo Soares Filho, Robert Gilmore Pontius, Michelle Farfán Gutiérrez, Hermann Rodrigues
A Suite Of Tools For Roc Analysis Of Spatial Models, Jean François Mas, Britaldo Soares Filho, Robert Gilmore Pontius, Michelle Farfán Gutiérrez, Hermann Rodrigues
Geography
The Receiver Operating Characteristic (ROC) is widely used for assessing the performance of classification algorithms. In GIScience, ROC has been applied to assess models aimed at predicting events, such as land use/cover change (LUCC), species distribution and disease risk. However, GIS software packages offer few statistical tests and guidance tools for ROC analysis and interpretation. This paper presents a suite of GIS tools designed to facilitate ROC curve analysis for GIS users by applying proper statistical tests and analysis procedures. The tools are freely available as models and submodels of Dinamica EGO freeware. The tools give the ROC curve, the …
Components Of Information For Multiple Resolution Comparison Between Maps That Share A Real Variable, Robert Gilmore Pontius, Olufunmilayo Thontteh, Hao Chen
Components Of Information For Multiple Resolution Comparison Between Maps That Share A Real Variable, Robert Gilmore Pontius, Olufunmilayo Thontteh, Hao Chen
Geography
This paper presents quantitative methods that allow scientists to compare the patterns in two maps that show a shared real variable. Specifically, this paper shows how to budget various components of agreement and disagreement between maps. The components are based on the separation of a map's information of quantity from its information of location. The technique also examines how variation in resolution influences the measurement of the components of information. The manner in which the measurements change as a function of spatial resolution can be more important and interesting than the results at any single particular resolution, because the results …
Expanding The Conceptual, Mathematical And Practical Methods For Map Comparison, Gilmore Robert Pontius, John Connors
Expanding The Conceptual, Mathematical And Practical Methods For Map Comparison, Gilmore Robert Pontius, John Connors
Geography
Conventional methods of map comparison frequently produce unhelpful results for a variety of reasons. In particular, conventional methods usually analyze pixels at a single default scale and frequently insist that each pixel belongs to exactly one category. The purpose of this paper is to offer improved methods so that scientists can obtain more helpful results by performing multiple resolution analysis on pixels that belong simultaneously to several categories. This paper examines the fundamentals of map comparison beginning from the elementary comparison between two pixels that have partial membership to multiple categories. We examine the conceptual foundation of three methods to …