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Particle Image Velocimetry Results

Metadata Updated: July 6, 2024

This child item contains the Mathworks Matlab mat-file outputs from the scripts described in the Ancillary Scripts child item. Each file contains the results for a particular field site. See the FGDC metadata Process Steps section for more information about opening these files. The mat-files included here have a standard set of output variables and include a variable named "zzVariableDescriptions" in each mat-file which describes the contents of the file. The following variables and descriptions are included in each mat-file (extracted from the "zzVariableDescriptions" variable): <br> <ul> <li><strong>calibration_distance:</strong> The distance between calibration points in meters.</li> <li><strong>calibration_points:</strong> Pixel coordinates of the calibration points. Format (array): [X1,Y1; X2; Y2]</li> <li><strong>calibration_time:</strong> Time increment between image frames in milliseconds.</li> <li><strong>caluv:</strong> Correction factor used to convert pixel/second into meters/second.</li> <li><strong>calxy:</strong> Pixel ground resolution in meters/pixel.</li> <li><strong>directory:</strong> Path to folder containing images used in PIV analysis.</li> <li><strong>filenames:</strong> Cell array of strings containing image frame filenames. Format (cellarray): 1m (m: number of frames)</li> <li><strong>imagesLocation:</strong> Path to folder containing images used in PIV analysis.</li> <li><strong>i:</strong> Dimensions of PIV results. Format: inumber of rows along y-axis</li> <li><strong>j:</strong> Dimensions of PIV results. Format: jnumber of columns along x-axis</li> <li><strong>k:</strong> Dimensions of PIV results. Format: knumber ofimages or frames in time (numbmer of images processed)</li> <li><strong>p:</strong> PIVLab image pre-processing settings. See PIVLab documentation for information.</li> <li><strong>pixel_resolution:</strong> Pixel ground resolution in meters. Assumes square pixels.</li> <li><strong>r:</strong> PIVLab post-processing settings. See PIVLab documentation for information.</li> <li><strong>resultsFileFullPath:</strong> Path to folder containing PIV results in mat-file format.</li> <li><strong>s:</strong> PIVLab standard processing settings. See PIVLab documentation for information.</li> <li><strong>typevector:</strong> Array (mnp) containing raw vector result type of frame (mn) for each frame (p). Format: type 1-valid PIV vector; type 0-masked vector; type 2-invalid PIV vector</li> <li><strong>typevector_filt:</strong> Array (mnp) containing filtered vector result type of frame (mn) for each frame (p). Format: type 1-valid PIV vector; type 0-masked vector; type 2-invalid PIV vector</li> <li><strong>u_mean:</strong> Array (mn) containing the temporal average u component of velocity in meters/second. Values are averaged for every vector for each frame (along p dimension).</li> <li><strong>u_stack:</strong> Array (mnp) containing filtered u component velocities for each vector (mn) for each frame (p).</li> <li><strong>v_mean:</strong> Array (mn) containing the temporal average v component of velocity in meters/second. Values are averaged for every vector for each frame (along p dimension).</li> <li><strong>v_stack:</strong> Array (mnp) containing filtered v component velocities for each vector (mn) for each frame (p).</li> <li><strong>x_ground:</strong> Array (mn) containing the x (horizontal) ground coordinate in meters for each PIV result vector. Origin of coordinates is the lower left corner.</li> <li><strong>x_pixel:</strong> Array (mn) containing the x (horizontal) pixel coordinate for each PIV result vector.</li> <li><strong>y_ground:</strong> Array (mn) containing the y (horizontal) ground coordinate in meters for each PIV result vector. Origin of coordinates is the lower left corner.</li> <li><strong>y_pixel:</strong> Array (mn) containing the y (horizontal) pixel coordinate for each PIV result vector.</li> <li><strong>zzVariableDescriptions:</strong> A structured array containing elements named after each variable in this dataset.</li> </ul> <br> Each Field Site is abbreviated in various files in this data release. File and folder names are used to quickly identify which site a particular file or dataset represents. The following abbreviations are used: <ul> <li>ACR: Androscoggin River, Auburn, Maine, USA</li> <li>AFR: Agua Fria River, near Rock Springs, Arizona, USA</li> <li>CCC: Coachella Canal above All-American Canal Diversion, California, USA</li> <li>CMC: Cochiti East Side Main Channel, near Cochiti, New Mexico, USA</li> <li>GLR: Gila River near Dome, Arizona, USA</li> <li>RMC: Reservation Main Canal near Yuma, Arizona, USA</li> <li>SMC: Sile Main Canal (at head) at Cochiti, New Mexico, USA</li> <li>WMD: Wellton-Mohawk Main Outlet Drain near Yuma, Arizona, USA</li> </ul>

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Created Date June 1, 2023
Metadata Updated Date July 6, 2024

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date July 6, 2024
Publisher U.S. Geological Survey
Maintainer
@Id http://datainventory.doi.gov/id/dataset/19f69f340aef2118cfd83aa1756d4f29
Identifier USGS:61eb31cfd34e8b818ada914b
Data Last Modified 20220214
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://datainventory.doi.gov/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 0674a97d-aa36-4c06-a40e-583f359890fa
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -114.94343,32.71551,-70.2241,44.0947
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash e8ce01221091753c0d79625e1775eaf87d99bb0d4419a7382a42c405737f96c6
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -114.94343, 32.71551, -114.94343, 44.0947, -70.2241, 44.0947, -70.2241, 32.71551, -114.94343, 32.71551}

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