William Acevedo
United States Geological Survey
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by William Acevedo.
Computers & Geosciences | 1997
William Acevedo; Penny Masuoka
Abstract Time-series animation is a visually intuitive way to display urban growth. Animations of landuse change for the Baltimore-Washington region were generated by showing a series of images one after the other in sequential order. Before creating an animation, various issues which will affect the appearance of the animation should be considered, including the number of original data frames to use, the optimal animation display speed, the number of intermediate frames to create between the known frames, and the output media on which the animations will be displayed. To create new frames between the known years of data, the change in each theme (i.e. urban development, water bodies, transportation routes) must be characterized and an algorithm developed to create the in-between frames. Example time-series animations were created using a temporal GIS database of the Baltimore-Washington area. Creating the animations involved generating raster images of the urban development, water bodies, and principal transportation routes; overlaying the raster images on a background image; and importing the frames to a movie file. Three-dimensional perspective animations were created by draping each image over digital elevation data prior to importing the frames to a movie file.
Environmental Monitoring and Assessment | 2017
Christopher E. Soulard; William Acevedo; Warren B. Cohen; Zhiqiang Yang; Stephen V. Stehman; Janis L. Taylor
Several spatial forest disturbance datasets exist for the conterminous USA. The major problem with forest disturbance mapping is that variability between map products leads to uncertainty regarding the actual rate of disturbance. In this article, harmonized maps were produced from multiple data sources (i.e., Global Forest Change, LANDFIRE Vegetation Disturbance, National Land Cover Database, Vegetation Change Tracker, and Web-Enabled Landsat Data). The harmonization process involved fitting common class ontologies and determining spatial congruency to produce forest disturbance maps for four time intervals (1986–1992, 1992–2001, 2001–2006, and 2006–2011). Pixels mapped as disturbed for two or more datasets were labeled as disturbed in the harmonized maps. The primary advantage gained by harmonization was improvement in commission error rates relative to the individual disturbance products. Disturbance omission errors were high for both harmonized and individual forest disturbance maps due to underlying limitations in mapping subtle disturbances with Landsat classification algorithms. To enhance the value of the harmonized disturbance products, we used fire perimeter maps to add information on the cause of disturbance.
SPIE/IS&T 1992 Symposium on Electronic Imaging: Science and Technology | 1992
Deborah Silver; William Acevedo
Our goal is to visualize the shape and structure in a data set of earthquake hypocenters collected from the island of Hawaii over a twenty-three year period. The earthquakes provide information about the magma system in this region and define a collection of conduits and reservoirs around the active volcanos. Because the data is scattered, traditional visualization methods are difficult to use (without interpolation). In this paper, we present some preliminary efforts to extract and define the structures within the data set.
Global Environmental Change-human and Policy Dimensions | 2012
Benjamin M. Sleeter; Terry L. Sohl; Michelle Bouchard; Ryan R. Reker; Christopher E. Soulard; William Acevedo; Glenn E. Griffith; Rachel R. Sleeter; Roger F. Auch; Kristi L. Sayler; Stephen Prisley; Zhiliang Zhu
Global Environmental Change-human and Policy Dimensions | 2013
Benjamin M. Sleeter; Terry L. Sohl; Thomas R. Loveland; Roger F. Auch; William Acevedo; Mark A. Drummond; Kristi L. Sayler; Stephen V. Stehman
Applied Geography | 2012
Terry L. Sohl; Benjamin M. Sleeter; Zhiliang Zhu; Kristi L. Sayler; Stacie L. Bennett; Michelle A. Bouchard; Ryan R. Reker; Todd J. Hawbaker; Anne Wein; Shuguang Liu; Ronald L. Kanengieter; William Acevedo
Circular | 2004
Roger F. Auch; Janis L. Taylor; William Acevedo
Land Degradation & Development | 2016
Christopher E. Soulard; William Acevedo; Stephen V. Stehman; Owen P. Parker
Archive | 2012
Roger F. Auch; Mark A. Drummond; Kristi L. Sayler; Alisa L. Gallant; William Acevedo
Professional Paper | 2006
William Acevedo; Janis L. Taylor; Dave J. Hester; Carol S. Mladinich; Sonya Glavac