|
The Interface (return to top) When you first access UASL you will be provided with a list of ALL the data layers present in the entire database - some of them are statewide in extent while others are much more limited in area. Clicking on any theme allows you to view the metadata in "short" or "full" views in the right window using the “short form” and “long form” buttons in the upper right. The Preferences obtion under the Edit menu allows you to set (1) your desired output formats and projections/datum for raster and vector data, (2) change your password and other user information and (3) save the current metadata and geographic search and selection criteria as a “Stored Filter.” You can later apply a stored filter using the “Apply Saved Filter” button on the upper toolbar. You can also create and remove both geographic and metadata filters using the icons that appear on the upper toolbar. The “Print List” button prints a list of all the selected feature classes and the “Print Metadata” prints out full FGDC compliant metadata for any single, selected feature class.”
GeoSurf Layer view Identifying data by theme, source, keyword or date (return to top) If you are interested in determining if there is data available · from a specific organization or source, (e.g. Arkansas Highway and Transportation Department, Environmental Protection Agency, etc.) · a particular thematic class (e.g. hydrology, infrastructure, etc.) · a particular date or range of dates or a · freeform keyword. You should click on the Metadata Filter button on the lower left of the layer view.
Metdata Filter window Categories are organized in major and (for some) minor categories. In some instances the same minor category can be found in different major categories. The major and minor categories are: GeopoliticalAdministrative areas Buildings HydrologyHydrostructure Water Waterways ImageryDOQ DRG Landsat InfrastructureAirports Bridges Buildings Hydrostructures Railroads Roads Utilities Waterways Natural ResourcesAnimals Climate Plants Subsurface Physical GeographyElevation Geology Landforms Land use/land cover Soils ReferenceSocioeconomicAgriculture Business Culture Education Elections Health Law enforcement Population
The sources and categories are selected from drop down lists. Freeform keyword searches can be conducted on the data base's metadata records. All layers in which the keyword occurs in the metadata are then displayed in the GeoSurf layer window. Click "Apply" to apply the selected metadata filter to the database. While the metadata filter is applied its contents will be displayed in the lower left part of the layer window. To remove the current metadata filter's restrictions click "Clear Metadata Filter" To return to the layer view without adding or changing the metadata filter click "Cancel." IMPORTANT NOTE If you have metadata restrictions that may be applicable in your search apply the metadata filter FIRST before doing a geographic search. Metadata filters are MUCH faster than geographic filters and by applying the metadata filter first you will reduce the number of layers to which a geographic filter is to be applied. Downloading statewide data (return to top) If you wish to obtain an entire statewide coverage, immediately after starting UASL, or after applying only a metadata filter, you can simply click on the desired feature class and then on the "Download" button on the lower right. If you have not applied any geographic filter, that is you DO want all the state, you will receive the following information message
No Geographic Filter dialogue If your intent is to acquire all the state just click “No” and proceed. Normally you will want to apply a geographic filter. So click “yes” and go back to create the geographic filter. Maximum output file size is 1 gigabyte (return to top) The maximum output file size permitted in UASL is 1 GB. If the file is larger than 1 GB you will be informed with the following message. You will need to reduce the size of your area of interest. The estimated output size is provided so you can determine how much you will have to reduce the area.
Output file too large error dialogue Determining if data is present in an area and/or extracting an area’s data (return to top) If you are interested in finding out if there is data in a selected area (smaller than the entire state) you will need to click the "Geographic Filter" button on the lower middle part of the "Layer Selection" dialogue. .
Geographic Filter dialogue Small area searches and data extractions When you perform a spatial filter in UASL the Oracle software uses what is called a fast, general "primary" filter. Any layers with data in the primary filter are returned. If you move to extract data, however, a second, more precise, extraction filter is used. In some cases, frequently in small areas, NO DATA may be found in the extraction. A small, special file will be prepared and delivered to the desktop informing the user of this situation. Using the geographic filter You can use the geographic filter to search for (and extract) data for areas defined by: A point location based on text or map entry of latitude/longitude street address UTM A box based on text or map entry An existing polygon Selection of area using a point The geographic point criteria can be entered in text dialogues and/or in a map viewer. In addition to the point an area extending out from that point is also defined using the slider bar at the bottom of the dialogue. The distance defines a square with the sides of the square at the defined distance from the point. The default is 200 miles. Clicking the desired radio button to the left will bring up different point dialogues
Dialogue to select a point by an address When you enter an address the address is geocoded using the MapInfo MapMarker geocoding engine. If there are ambiguous results a dialogue will pop-up listing the alternatives and asking you to select the proper one.
Multiple address location dialogue If you are satisfied with the criteria you can click "Apply" and UASL will search for all data that is present in the defined area. Prior to clicking "Apply," if you wish to view the location on an interactive map, you can click on "Show Map" and you can view and/or change the point location. The map viewer operation will be discussed later. Important note on address: The geocoding utilizes available address information. For may areas in the state this is quite good but for others there is little address information, particularly in rural areas. An address such as “Rural Route 1” will not return an accurate address. In other areas there are addresses but they are not well mapped. In these cases the geocoding will frequently return the center of the address’s zip code boundary. Defining a box for a search (return to top) Clicking on the "Bounding Box" tab on the "Geographic Filter" dialogue will bring up the "Bounding box" dialogue.
Bounding box dialogue You can type in four latitude/longitude values - using decimal degrees. The values should be NAD83 based. Clicking on the "Show Map" dialogue when the bounding box tab is selected will allow you to interactively draw the box on a map. This operation is discussed later. Searching (and extracting) data using a predefined polygon (return to top) You can search (and extract) data from UASL using a number of predefined polygons. The classes of polygons are:
Defined polygon dialogue for hydrologic unit
Existing polygon dialogue for Township/Range and Sections The various data sets that were originally based on preexisting boundaries, such as the DLG data from USGS based on 7.5 minute quadrangle maps, have been merged into statewide, seamless data sets in UASL. However - if you already have data organized by these areas you can use (for example) the predefined USGS quad polygons to obtain data that will be compatible with your existing data. The data is being interactively clipped from the seamless coverage. IMPORTANT NOTES: Searching using a predefined polygon MUST be performed if you wish to extract data in that polygon. Predefined polygon based searching is slower than box or point searcher. Be sure to apply any applicable metadata filters FIRST to speed up the response.
Predefined quadrangle dialogue Viewing the geocoded street address, points, or box (or interactively drawing them – if desired) (return to top) Clicking on the "show map" button with either the "Point Location" tab or Bounding box tab selected will bring up the interactive map option. You will be able to view the point or box you defined and/or you can interactively define a point or box.
The interactive map window There are two sets of "controls" in the interactive map viewer. The "Map Control" and "Filter." "Map Control" buttons allow you to zoom in and out, pan etc. but they do NOT change the location of the selected point or box. The filter buttons are the only tools that allow you to change the location of a point or the extent of a box.
IMPORTANT NOTE: Any actions in either the text boxes or on the map are not in effect until you click on the Apply button to the lower left of the window. As you zoom in and out various reference map layers are displayed. Note that the map window layers are ONLY for geographic location reference - the data layers are NOT displayed in the map window.
Map detail at an intermediate level of zoom
Map detail at a high level of zoom Reviewing data layers (return to top) Once the required metadata and/or geographic filters are applied the Layer Selection window will display all data layers that meet the filtering criteria.
Layer window with data layers meeting filter criteria There are two forms of the metadata report (short and long). The short version is shown above and a portion of the long version is shown in the following figure.
Metadata long version Printing out data list and metadata (return to top) It is possible to print a list of the data sets that are present in the search area or to print out the detailed metatdata about any selected feature class. Click the “Print List” button on the Layer Selection dialogue to print a complete list of the data that is currently within the search filter’s parameters. You will then see the Print dialogue
Print dialogue You can send the data directly to any accessible printer or you can send it to a file. Note: you MUST first click on the “To File” radio button before you can use the file browser (indicated by the three dots to the right of the file name field). You can set the character width character spacing for tabs and whether there is a DOS style line break or a Unix style line break. Selecting the Print Metadata option brings up the same Print dialogue. You MUST FIRST SELECT a feature class using the mouse before the Print Metadata option will work. Downloading data (return to top) If the desired data is present you can move to download the data by clicking on the "Download" button. If the data type selected is Vector a Vector Parameter dialogue will appear. If it is Raster data a Raster Parameter will appear. Vector download parameters (return to top) The Vector Parameter dialogue is shown below. Download Vector Parameters dialogue The entry for “Coordinate System” and “ Format” will either be the default ones or the ones you have set as your “ User Preference” (go to “Setting User Preferences” for instructions). If these are OK just click “Submit.” You can select different Formats and Coordinate Systems by simply using the drop down list and clicking on the desired format. Doing this does NOT change your saved “User Preferences.” Formats for vector data (return to top) The "Select format for vector layers:" drop down is used to indicate the desired data/vendor format. The UASL 3.0 options are:
Vector selection via either a touch or a boundary selection (return to top) A final factor is whether the vector data is to be clipped to the boundary of the area or if touching is used. In a boundary clip any line or polygon that has all or part within the search area is clipped at the edge of the bounding box or polygon. Using touch all the line or polygon of any element (feature/object) that is wholly or partly within the search area are delivered even if only a part of the line or polygon touches the search area. Raster download parameters (return to top) The Raster Parameter dialogue is shown below.
Raster Parameter Dialogue Use the dropdown lists to set the coordinate system and the file format that will automatically be applied to the raster data. Formats for raster data (return to top) Raster data is delivered in a range of possible formats. They are: · GeoTIFF · ArcInfo Band Interleaved · ArcInfo ASCII GRID · ENVI Raster · ERDAS IMG · ERDAS Lan · PCI Raster (PIX) 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. Projections/datum (return to top) The desired projection/datum for the data is selected using the "Select coordinate system:" dialogue. The UASL 3.0 options are:
Data delivery (return to top) Once you submit your request UASL begins processing your data. Generally vector data is processed very quickly while raster may be quite time consuming. As soon as the data processing is completed on the UASL server your e-mail is automatically mailed a message. The body of the message contains a URL. If you click on that URL in most mail systems the download of the data will begin. For older, text-based mail systems the user will need to note the URL and enter it later in a browser. Each job is provided with a unique job –id. If you have problems or questions please note the ID number. In the below message it’s 50964. Data will remain on the server for 72 hours after completion and then it will be automatically removed. The data will remain after a download so you may return and download again – if the 72 hours have not expired. Data delivery message Setting user password and user information. (return to top) The User Information Tab in the Preferences dialogue allows you to change your password and to update/add other user information. The dialogue is shown below.
User Information Dialogue Contents of the zip files (return to top) Each of the zip files will have an FGDC compliant metadata file for the selected data in a html format. It will also contain a number of other files and the contents of the zip files will vary depending on the vendor format selected. For ESRI shape files, for example, the zip file will contain four files that have the extensions .shp, .shx, .dbf and .prj. You will need to use one of the various unzipping software packages that are available and place the extracted files in the proper place on your local machine. Saving and using search and selection criteria (return to top) You may wish to return to a same location in a future UASL access and to extract data from the same area or (if you have more than five (5) simultaneous jobs in the queue) you will be REQUIRED to either wait or return. You do not need to laboriously recreate a search criteria but can save them for future use as a stored filter. To save search and selection criteria – both the metadata AND the geographic component - you can use the “Stored Filter” tab in the Preferences tab.
Stored filter dialogue To use the stored filter option you MUST first create a filter using the standard UASL metadata and geographic tools. Once you have the search and selection criteria set you need only click on the Preference tab in the “Data Selection Dialogue” and then on “Stored Filter” tab. Clicking on the “Save Current Filter” tab will make the current filter the stored one. You can now exit UASL and, when you return, you can quickly apply the same criteria. The “Clear Saved Filter” clears the search and selection filter. When returning to UASL, if you want to use the stored filter you MUST click on the “Apply Saved Filter” button in the upper left of the Layer Selection dialogue.
Apply Saved Filter button Comments and suggestions (return to top) We warmly invite your comments and suggestions for this help document. Please e-mail and comments or suggestions to UASL@cast.uark.edu. |
These buttons are used to zoom in (plus)
and out (minus). Remember that zooming the map does NOT change the point
or box coordinates. The measurement shown in the map width box at the
lower left of the map is NOT the search/extract bounding box value.
It is simply the extent of the current map window view. You can only
change the search/extract extent with the slider bar on the text side of
the window.
This button pans the map. Again - remember
that panning does NOT alter the point or box values. It is also possible
to pan (or zoom) and NOT have either the point or box within the current
window!
Clicking this button returns the map to
the complete state.
Clicking this button moves the selection
to "point" mode - the "Point Location" tab will automatically move to the
front of the text area when you select this button. A new point will be
located on the map where ever you click the mouse. Note that the area to
be searched (and/or extracted) around the point is set using the slider
bar on the "Point Location" tab. 
Clicking this button will shift the area
selection to bounding box selection/extraction mode and the "Bounding Box"
dialogue will shift to the top of the text area automatically. As you draw
various boxes on the screen note that the coordinates in the bounding box
dialogue are automatically updated. 
