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All available digital map data for the state of
Arkansas will be in GeoStor. This includes roads, streams, aerial
photography, satellite imagery, and elevation data. There are more
than 200 vector feature classes (e.g.. roads, soils) and more than 350
raster ones (including statewide aerial photography, elevation,
satellite imagery etc.). The AHTD is cooperating with the State Land
Information Board to provide the AHTD county map files as
well.
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GeoStor allows you to search for digital
map data in Arkansas and download just what you want. You
can request the data to be prepared in any of a number of vendor
formats and projections/datums. When you submit your request the
system begins processing it and will send you an e-mail with the FTP
link to access the data. Simply click on the link and the data will be
downloaded to your computer.
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You can search by many different easy-to-use
criteria: (a) address, (b) place (e.g. city-limits, county, park
boundaries), (c) point in UTM, lat/lon or SPSC coordinates, (d) box
drawn on screen, (e) Township/Range/Section and/or (f) theme keyword
(e.g. elevation, soils).
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Once you have identified the data you want
GeoStor extracts the area you select, converts it to the software
format and the datum/projection you select and downloads it to your
computer over the internet.
What happens when the data I want is "on"
multiple maps ? Do I have to download all of them ? (return
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Unlike other systems GeoStor’s data is "seamless" –
existing maps have been merged into one single statewide map and you
select ONLY the area you want. It doesn’t matter where it is. You DO
NOT have to know what map applies to your area.
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There are no GIS skills needed to use GeoStor.
However, GeoStor provides digital data and you will need to be able to
use the data. GeoStor is NOT an online mapping
system.
How difficult will this be, since I have
little computer experience? (return
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Anyone who can use the World Wide Web can use GeoStor,
no GIS skills are needed.
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GeoStor delivers data to your desktop computer
in many different formats and you can immediately merge it with your
own data.
Do I get to view the layers or do I just
select them from a list? (return
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After you have defined your criteria (by area or topic)
the ones in the database that meet the criteria are displayed in a
list. You then select the layers you want from that list. GeoStor is
not a map viewer.
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There is no cost to the end-user. The State Land
Information Board is requesting funds to support its continuing
operation.
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Anyone with access to the World Wide Web can
access GeoStor. Depending on the providing agency’s requirements,
there may be certain data classes that are "advertised" in GeoStor but
that cannot be freely downloaded, but the great majority
can.
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Technically GeoStor can provide data in more than
50 different vendor formats. The operational systems will support
all common formats including AutoDesk, ESRI, Intergraph, MapInfo,
and many others. It is also fully compliant with the Open GIS
Consortium’s spatial data specifications.
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Yes. Data can be delivered to you for just the limits
of any "place" in the database including cities, counties, parks,
sections and any named Census place.
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You
will need access to the World Wide Web and a web browser. At this
point GeoStor works best with Microsoft’s Internet Explorer Version
5.x. It should work smoothly with the 6.x release of Netscape when
these are available. GeoStor will work
smoothly with Netscape 4.5 or higher but these versions of Netscape
currently do not properly recognize security certificates. We are
working to determine how this issue can be
addressed.
Can GeoStor data be updated easily ? And
how often will it be updated? (return
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GeoStor is designed using a new
"transactional" geospatial data model – its design allows "immediate"
updates to be posted to individual features. For example, if a road is
moved only that single change needs to be made to the database. How
and when it will be updated, however, is an administrative decision
that will depend on resources and agency
agreements.
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Technically GeoStor can provide data in more than 50
different vendor formats. The operational systems will support all
common formats including AutoDesk, ESRI, Intergraph, MapInfo, and many
others. It will also provide the data in user selected map projections
and datums. It is also fully compliant with the Open GIS Consortium’s
spatial data specifications.
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No one. The project is the first state data system
to take advantage of a wide range of new developments in spatial data
organization and storage. Because of its innovative nature the project
received an Smithsonian-ComputerWorld Innovation Award in
1999.
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You can clip by (1) defined extent (e.g. 10 km)
around a point or address, (2) by a box (either drawn on the map or
with coordinates entered) (3) by any defined polygon including
counties, Census places, parks, etc. Both vectors and rasters can be
clipped.
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If the data are seamless you don’t have to
download multiple maps and connect (mosaic) them together. If you have
a project area that is at the corner of four maps you don’t
have to download four different maps, mosaic them and then cut out the
piece you need. In GeoStor you simply identify the small area you need
- only that part is seamlessly delivered to you
immediately.
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Yes. The AHTD is cooperating with the State Land Information
Board to provide the very useful AHTD county files in GeoStor.
The AHTD CAD files are separated into more than 75 different individual
themes (e.g. corporation limits, chicken houses, dwellings - outside
of corporation limits). Each theme can be individually selected.
The data will then be provided in your own defined GIS/CAD format
and projection/datum.
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GeoStor is designed to allow you to identify and
acquire data, it is not an "on-line mapper". However, the data in
GeoStor serves as the "back end" to different on-line mapping systems.
The Arkansas Economic Development Atlas is one example. You can access
the Atlas at www.cast.uark.edu/cast/econ_dev
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You will need access to the World Wide Web and a
web browser. At this point GeoStor works best with Microsoft’s
Internet Explorer Version 5. It should work smoothly with the 6.x
release of Netscape when these are available. GeoStor will work
smoothly with Netscape 4.5 or higher but these versions of Netscape
currently do not properly recognize security certificates. We are
working to determine how this issue can be
addressed.
How do you plan to address large files and
long download times ? (return
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User can create data file that can be as large
as 1 GB. A file this large would be practically impossible to download
over a slow telephone line. Because the user can select only a
small area of interest, the files sizes are usually MUCH smaller that
in other systems that use standard map files. Subject to
cooperation from the vendors, we plan to add file compression to the
raster file formats. The vector file are usually fairly
small but
the raster files can be very large. It is our hope that we can add
user selectable compression options. In the meantime MrSID compressed
statewide color DOQQs are available for individual download at
http://www.cast.uark.edu/cast/geostor/raw_DOQ/index.html
In our community we use state plane
coordinates and most federal data is in UTM and needs to be converted.
What does GeoStor use? (return
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GeoStor’s internal data format is geographic NAD83.
However, the user can select a wide range of map projections and
datums and the data will be re-projected before it is downloaded to
you. More than 150 projections/datums are technically supported but
only the commonly used ones are available. They include UTM, State
Plane and Lat/Lon NAD27 and NAD83. Others can be added if needed.
How does GeoStor differ from other state’s
on-line systems? (return
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Yes. All data have FGDC compliant metadata and
information on the data sets will be accessible via the FGDC
clearinghouse system.
If you are seamlessly merging multiple
data files, how is metadata organized? (return
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Aggregated metadata has been developed for each
seamless theme (feature classes) that is composed of individuals map
tile data (e.g. metadata entry for "date" will be a range of earliest
and most recent tile dates). In addition, however, a set of metadata
"themes" will also be developed that reflects the original source
metadata. For example, associated with the 1:24K quad boundary map
will be quad map boundary theme and a table that contain the original
metadata for each "theme" in each quad. If desired the user can
recover the original metadata for the original map
tiles.
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As of July 2002, it has more than 2 terabytes of
data.
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The
geographic data in GeoStor are placed in an Oracle Enterprise Spatial
Database with GeoImage extension running on a SunMicrosystems
Enterprise class server. The geographic and attribute components of
each feature (e.g. "Highway 1") are stored as an object in the
database. The data are indexed using a quadtree index that provides
fast access. MapXtreme 3.0 (MapInfo Corporation) has been used to
create the interface. Data is converted and re-projected using the
Feature Manipulation Engine (FME, Safe Software’s) which was also used
to load much of the data. GeoGateway software (PCI GeoMatics) is used
to re-project raster data and is used to load much of the raster data.
ArcSDC and ArcIMS 3.0 (ESRI’s) is used as the
basis for the soils mapping and analysis system. GeoMedia
(Intergraph), ER Mapper (ER-Mapper) and ArcInfo 8 (ESRI) were used to
create seamless data sets and manipulate the data before
loading.
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On the main data lister page click on the
Preferences button. In the Preferences dialogue select the "User
Information" tab. Enter your desired new password in the two
fields.
How do I set my user preferences for raster and vector
formats (return
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On the main data lister page click on the
Preferences button. In the Preferences dialogue select the "Raster" or
"Vector" tab. From the drop down list you can select the
projection/datum and format you want. These formats will automatically
be applied to future downloads. You can change them at any
time.
Why does it sometimes say that my raster format is
unacceptable? (return
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Because of the different properties of various raster data not
all output formats are supported for all data types. The following
output formats are supported for each data type.
1.
One band, eight bit images -
Landsat data bands and B/W DOQQs.
Output formats available: ARC.bil, ARC.grd, ENVI.nvi,
ERDAS.lan, PCI.pix and TIFF.tif.
2. Three band
eight bit images – Landsat color composites, CIR DOQQs.
Output formats available: ARC.bil, ENVI.nvi, ERDAS.lan, PCI.pix
and TIFF.tif.
3.
One band, sixteen bit images – Digital elevation models, grid data
with more than 256 values.
Output formats available: ARC.bil, ARC.grd, ENVI.nvi, ERDAS.lan
and PCI.pix.
4.
One band, eight bit data with a pseudo-color table – LULC and GAP
maps, Digital Raster Graphics, various thematic gridded
data.
Output formats available: PCI.pix and TIFF.tif.
Please be aware that only the appropriate options will be
available in the GeoStor output data format selection drop down. If you have selected a data
set, such as the statewide LULC data, whose native formats is one
band, eight bit then the only output formats possible in the drop down
will be PCI-pix and TIFF.tif.
Alternatively, if you selected a single Landsat band then all
the formats would be
available. |
