<?xml version="1.0" encoding="ISO-8859-1" ?>
- <metadata>
- <idinfo>
- <citation>
- <citeinfo>
  <origin>Corps of Engineers, St. Louis District</origin>
  <pubdate>20120731</pubdate>
  <title>NE_1170_0460_b</title>
  <geoform>remote-sensing image</geoform>
- <pubinfo>
  <pubplace>US Army Corps of Engineers St. Louis District</pubplace>
  <publish>US Army Corps of Engineers St. Louis District</publish>
  </pubinfo>
  </citeinfo>
  </citation>
- <descript>
  <abstract>Fugro Horizons Inc acquired LiDAR with Leica sensor ALS60 MPiA for the North Platte River. This portion of the North Platte River covers areas in Nebraska totaling 1447 square miles. Acquisition occured fall 2011. The ALS60 sensor settings included acquisition at 7,000' AMT, 150 knots, 15% sidelap, pulse rate 109,600Hz, scan rate 31.5Hz, 34 degree field of view, 4,2ft swath width, maximum along track spacing (occurs at FOV edge) of 2.3m in overlap areas, maximum cross track spacing (occurs at Nadir) 1.1 meter, 3sigma post spacing of 1.34m. The sensor was equipped with IPAS inertial measuring unit (IMU) and a dual frequency airborne GPS receiver. These settings were used to meet or exceed 15cm vertical RMSE in flat areas with minimial vegitation. Final deliverables for the LiDAR are in Nebraska State Plane coordinate system NAD86(2007) NAVD88 Geod09 meters tiled 5,000ft x 5,000ft with an XY naming convention. DELIVERABLES Classified LAS files Model key Point LAS files ESRI 1m DEM 2 foot contours in ESRI Geodatabase and Microstation formats Hydro Enforced Breaklines Hillshade Images ACQUISITION DATES November 10 2011 November 11 2011 November 12 2011</abstract>
  <purpose>To provide data for others to visually denote and quantify inundation damage areas from no damage areas and quantify damage as heavy, moderate, or light</purpose>
  </descript>
- <timeperd>
- <timeinfo>
- <rngdates>
  <begdate>20111110</begdate>
  <enddate>20120731</enddate>
  </rngdates>
  </timeinfo>
  <current>Publication Date</current>
  </timeperd>
- <status>
  <progress>Complete</progress>
  <update>Unknown</update>
  </status>
- <spdom>
- <bounding>
  <westbc>-101.689572</westbc>
  <eastbc>-101.671075</eastbc>
  <northbc>41.11141</northbc>
  <southbc>41.097419</southbc>
  </bounding>
  </spdom>
- <keywords>
- <theme>
  <themekt>None</themekt>
  <themekey>LiDAR Acquisition</themekey>
  <themekey>LiDAR</themekey>
  <themekey>LiDAR 1.4m</themekey>
  <themekey>USACE St Louis District</themekey>
  <themekey>North Platte River</themekey>
  </theme>
- <place>
  <placekt>Geographic Names Information System</placekt>
  <placekey>NE</placekey>
  <placekey>Nebraska</placekey>
  <placekey>North Platte River</placekey>
  </place>
  </keywords>
  <accconst>There are no limitations for access.</accconst>
  <useconst>None</useconst>
- <ptcontac>
- <cntinfo>
- <cntorgp>
  <cntorg>USACE ST Louis District</cntorg>
  </cntorgp>
- <cntaddr>
  <addrtype>mailing and physical address</addrtype>
  <address>US Army Corps of Engineers St. Louis District 1222 Spruce Street</address>
  <city>St. Louis</city>
  <state>MO</state>
  <postal>63103-2833</postal>
  <country>USA</country>
  </cntaddr>
  <cntvoice>(314) 331-8389</cntvoice>
  <hours>8am to 5pm Central Time</hours>
  <cntinst>http://www.mvs.usace.army.mil/</cntinst>
  </cntinfo>
  </ptcontac>
- <browse>
  <browsen>None</browsen>
  <browsed>None</browsed>
  <browset>None</browset>
  </browse>
  </idinfo>
- <dataqual>
- <attracc>
  <attraccr>GPS phase data was post processed with continuous kinematic survey techniques using "On the Fly" (OTF) integer ambiguity resolution. The GPS data was processed with forward and reverse processing algorithms. The results from each process, using the data collected at the airport and in project area, were combined to yield a single fixed integer phase differential solution of the aircraft trajectory. The differences between the forward to reverse solution within the project area were within project specifications, indicating a valid and accurate solution. An IMU was used to record precise changes in position and orientation of the LIDAR scanner at a rate of 200 Hz. All IMU data was processed post flight with a filter to integrate inertial measurements and precise phase differential GPS positions. The resulting solution contains geodetic position, omega, phi, kappa, and time for subsequent merging with the laser ranging information.</attraccr>
  </attracc>
  <logic>Tiling is based on the State Plane coordinates.</logic>
  <complete>Complete</complete>
- <posacc>
- <horizpa>
  <horizpar>Meets or exceeds horizontal accuracy of 0.6m RMSE 1.04 m at the 95% confidence level.</horizpar>
  </horizpa>
- <vertacc>
  <vertaccr>Vertical elevations will meet or exceed 15.0 cm RMSE 0.30m at the 95% confidence level for bare earth products.</vertaccr>
  </vertacc>
  </posacc>
- <lineage>
- <srcinfo>
- <srccite>
- <citeinfo>
  <origin>USACE ST Louis District</origin>
  <pubdate>20120731</pubdate>
  <pubtime>Unknown</pubtime>
  <title>North Platte River LiDAR mapping</title>
  </citeinfo>
  </srccite>
  <typesrc>Digital copy</typesrc>
- <srctime>
- <timeinfo>
- <rngdates>
  <begdate>20111110</begdate>
  <enddate>20120731</enddate>
  </rngdates>
  </timeinfo>
  <srccurr>Publication Date</srccurr>
  </srctime>
  <srccitea>Georectifed LiDAR data sets</srccitea>
  <srccontr>Digital Georectifed LiDAR.</srccontr>
  </srcinfo>
- <procstep>
  <procdesc>AeroScan LiDAR timed reflection data and the IMU SOL flies were processed together using LiDAR processing software. The data set for each flight line was checked for project area coverage, data gaps between overlapping flight lines, and tension/compression areas (areas where data points are more or less dense than the average project specified post spacing). Using an iterative process that involves analyzing raster difference calculations the omega, phi, kappa angle corrections for the LiDAR instrument were determined. Corrections were applied to the LiDAR data set. Extensive comparisons were made of vertical and horizontal positional differences between points common to two or more LiDAR flight lines. An intensity raster for each flight line was generated and verified that intensity was recorded for each LiDAR point. LiDAR ground points were compared to independently surveyed and positioned ground control points at both the airport bore-sight area and the project area. Based on the results of these comparisons, the LiDAR data was vertically biased to the ground. (1) PRE-PROCESSING STAGE LiDAR, GPS and IMU data are processed together using LiDAR processing software. The LiDAR data set for each flight line is checked for project area coverage and LiDAR post spacing is checked to ensure it meets project specifications. The LiDAR collected at the calibration area is used to correct the rotational, atmospheric, and vertical elevation differences that are inherent to LiDAR data. Intensity raster is generated to verify that intensity was recorded for each LiDAR point. LiDAR data is transformed to the specified project coordinate system. By utilizing the ground survey data collected at the calibration site and project area, the LiDAR data is vertically biased to the ground. Comparisons between the biased LiDAR data and ground survey data within the project area are evaluated and a final RMSE value is generated to ensure the data meets project specifications. LiDAR data in overlap areas of project flight lines is removed and data from all swaths is merged into a single data set. The data set is trimmed to the digital project boundary including an additional buffer zone, which is typically about 50 meters (buffer zone assures adequate contour generation from the DEM). The resulting data set is referred to as the raw LiDAR data. (2) SURFACING STAGE The raw LIDAR data is processed through a minimum block mean algorithm and points are classified as either bare earth or non-bare earth. User developed "macros" that factor mean terrain angle and height from the ground are used to determine bare earth point classification. The next phase of the surfacing process is a 2D edit procedure that ensures the accuracy of the automated feature classification. Editors use a combination of imagery, intensity of the LiDAR reflection and tin-editing software to assess points. If required, the LiDAR data is filtered as necessary, using a quadric error metric to remove redundant points to generate a keypoint class. This method leaves points where there is a change in the slope of surfaces (road ditches) and eliminates points from evenly sloped terrain (flat field) where the points do not affect the surface. When other classifications and derived products are required, various applications and proprietary algorithms are used to meet each customer's unique requirements.</procdesc>
  <procdate>20120731</procdate>
  </procstep>
  </lineage>
  </dataqual>
- <spref>
- <horizsys>
- <planar>
- <gridsys>
  <gridsysn>State Plane Coordinate System 1983</gridsysn>
- <spcs>
  <spcszone>Nebraska</spcszone>
- <lambertc>
  <stdparll>40.0</stdparll>
  <stdparll>43.0</stdparll>
  <longcm>-100.000000</longcm>
  <latprjo>+39.833333</latprjo>
  <feast>1640416.666667</feast>
  <fnorth>0.0</fnorth>
  </lambertc>
  </spcs>
  </gridsys>
- <planci>
  <plance>row and column</plance>
- <coordrep>
  <absres>.001</absres>
  <ordres>.001</ordres>
  </coordrep>
  <plandu>Survey Feet</plandu>
  </planci>
  </planar>
- <geodetic>
  <horizdn>North American Datum NAD83 (NSRS2007)</horizdn>
  <ellips>Geodetic Reference System 80 (GRS 80)</ellips>
  <semiaxis>6378137</semiaxis>
  <denflat>298.257222101</denflat>
  </geodetic>
  </horizsys>
- <vertdef>
- <altsys>
  <altdatum>North American Vertical datum of 1988 Geoid09</altdatum>
  <altres>.001</altres>
  <altunits>Survey Feet</altunits>
  <altenc>Implicit coordinate</altenc>
  </altsys>
  </vertdef>
  </spref>
- <eainfo>
- <overview>
  <eaover>1.4m LiDAR Acquisition and Processing.</eaover>
  <eadetcit>None</eadetcit>
  </overview>
  </eainfo>
- <distinfo>
- <distrib>
- <cntinfo>
- <cntorgp>
  <cntorg>USACE ST Louis District</cntorg>
  </cntorgp>
- <cntaddr>
  <addrtype>mailing and physical address</addrtype>
  <address>US Army Corps of Engineers St. Louis District 1222 Spruce Street</address>
  <city>St. Louis</city>
  <state>MO</state>
  <postal>63103-2833</postal>
  <country>USA</country>
  </cntaddr>
  <cntvoice>(314) 331-8389</cntvoice>
  <hours>8am to 5pm Central Time</hours>
  <cntinst>http://www.mvs.usace.army.mil/</cntinst>
  </cntinfo>
  </distrib>
  <distliab>In no event shall the creators, custodians, or distributors of this information be liable for any damages arising out of its use (or the inability to use it).</distliab>
  </distinfo>
- <metainfo>
  <metd>20120731</metd>
- <metc>
- <cntinfo>
- <cntorgp>
  <cntorg>USACE ST Louis District</cntorg>
  </cntorgp>
- <cntaddr>
  <addrtype>mailing and physical address</addrtype>
  <address>US Army Corps of Engineers St. Louis District 1222 Spruce Street</address>
  <city>St. Louis</city>
  <state>MO</state>
  <postal>63103-2833</postal>
  <country>USA</country>
  </cntaddr>
  <cntvoice>(314) 331-8389</cntvoice>
  <hours>8am to 5pm Central Time</hours>
  <cntinst>http://www.mvs.usace.army.mil/</cntinst>
  </cntinfo>
  </metc>
  <metstdn>FGDC Content Standards for Digital Geospatial Metadata</metstdn>
  <metstdv>FGDC-STD-001-1998</metstdv>
  </metainfo>
  </metadata>