Source
The NED dataset is a compilation of data from a variety of existing high-precision datasets such as LiDAR data (see also National LIDAR Dataset - USA), contour maps, USGS DEM collection, SRTM and other sources which were reorganized and combined into a seamless dataset, designed to cover all the United States territory in its continuity.
Read more about this topic: National Elevation Dataset
Famous quotes containing the word source:
“As a means of contrast with the sublime, the grotesque is, in our view, the richest source that nature can offer.”
—Victor Hugo (1802–1885)
“The child knows only that he engages in play because it is enjoyable. He isn’t aware of his need to play—a need which has its source in the pressure of unsolved problems. Nor does he know that his pleasure in playing comes from a deep sense of well-being that is the direct result of feeling in control of things, in contrast to the rest of his life, which is managed by his parents or other adults.”
—Bruno Bettelheim (20th century)
“If all else perished, and he remained, I should still continue to be; and if all else remained, and he were annihilated, the universe would turn to a mighty stranger. I should not seem a part of it.... My love for Heathcliff resembles the eternal rocks beneath—a source of little visible delight, but necessary. Nelly, I am Heathcliff—he’s always, always in my mind—not as a pleasure, any more than I am always a pleasure to myself—but as my own being.”
—Emily Brontë (1818–1848)