170 likes | 281 Views
Midterm next Wednesday. Midterm. May start off with multiple choice Bulk will be short answer/short essay Lecture PPTs and your notes , readings in Longley et al., Zeiler Will not include Labs or Arc Marine exercise Journal articles. Major concepts. Representations Object vs Field
E N D
Midterm • May start off with multiple choice • Bulk will be short answer/short essay • Lecture PPTs and your notes, readings in Longley et al., Zeiler • Will not include • Labs or Arc Marine exercise • Journal articles
Major concepts • Representations • Object vs Field • Model, data model, analysis model • Data models • UML terminology, basic procedure from • Reality --> conceptual --> logical --> physical • Customized Arc GIS data models • For enterprise GIS • Analysis Models • Binary, ranking, rating, weighted rating
Major concepts - cont. • Geodatabase • what it is, why it’s important • Topology, Spatial Analysis • what they are, why they are important, how they relate • Object orientation • Identity, inheritance, encapsulation • Data Sharing (barriers) • Desktop to Cloud Discussion
NSDI ---> data.gov • Who needs to share data? • jurisdictions with common borders • jurisdictions in a region • private and public sectors • local, state, and Federal agencies • government and individuals
NSDI ---> data.gov • State, local, private production of geospatial data • loss of Federal monopoly, patchwork • variable accuracy, level of detail • the WWW • everyone can be a producer, publisher, distributor of geospatial data • See GEO 465/565 lecture #6 • dusk.geo.orst.edu/gis/lec06.html#nsdi
Barriers to Data Sharing (1) interoperability • will ArcGIS read Intergraph data? • find a common format that both can read • output into the common format • input the common format • is the common format the same as one of the GIS formats? • if yes, only one conversion is needed • if no, two conversions are needed • issues of format, syntax within ONE GIS
Digital Line Graphs (DLGs) • vector topographic maps • 1:24,000, 1:100,000 ,1:10,000
Govt Agency Data Formats • Digital Raster Graphics (DRGs) • raster topographic maps at 1:24,000 • Digital Elevation Models (DEMs) • raster elevation data • 90m, 30m, 10m • Oregon 10m DEMs from buccaneer.geo.orst.edu/dem
Govt Agency Data Formats • Digital Orthophoto Quads (DOQs or DOQQs) • aerial photographs • camera orientation, terrain info. • raster images at 1m resolution • 6m positional accuracy at scale of 1:12000 • Imagery • satellites • Landsat, SPOT, SPIN, etc.
National Data Sharing (cont.) • new high resolution commercial imagery • 1 m resolution • www.spaceimaging.com
Barriers to Data Sharing (2) how to describe what you need • how to assess whether some data set fits the need?
Describing Data • Metadata • Again, see GEO 465/565 lecture #6 • dusk.geo.orst.edu/gis/lec06.html#nsdi • ArcCatalog • graphic thumbnail • Tables • FGDC format metadata • ESRI format metadata • XML format metadata
Issues with metadata? • potential complexity • can be larger than the data set! • investment to create • can be larger than the data set! • carrots and sticks • FGDC’s "don't duck metadata"
Barriers to Data Sharing (3) retrieval - large spatial data sets (4) national security - e.g., impact of 9/11 (5) search engines • how to know where to look on the WWW? • SAPs know where to look (more on this soon) • National clearinghouse, www.data.gov • Regional and campus clearinghouses • www.geo.oregonstate.edu/ucgis/datasoft.html • Google