Multitemporal Site URL List 1|]# image products with accurate spatial co-registration will facilitate manual or semi-automated detection of changes. LFDC systems may be preferable to large format film cameras for imaging large extents of the border because no film purchase, processing, or scanning is required in the creation of the digital images. In addition, a completely digital workflow may result in faster and more efficient product generation.Researchers at the Department of Geography at San Diego State University (SDSU) are working with personnel from the San Diego Sector of the USBP to assess the utility of commercially available imagery from LFDC systems for border monitoring and change detection.
As part of this assessment, SDSU researchers surveyed companies operating ADS40, DMC, and UltraCam LFDC systems within the United States and asked these companies if Inhibitors,Modulators,Libraries they would Inhibitors,Modulators,Libraries be willing to collect and provide demonstration data sets for the evaluation. Six companies responded to the survey, and four of these companies provided custom imagery or data processing services.2.3. Large Format Digital Camera SystemsThe ADS40 system is a line array system that employs the three-line scanning technique, in which multiple linear charge coupled device (CCD) arrays are situated on the focal plane within a single sensor head and view in the forward, nadir, and backward direction. The ADS40 uses large (12,000 pixel) linear CCD arrays which yield wide cross-track image coverage per flight line [10].
Each line of imagery is acquired over a unique time period and is associated with a unique aircraft position and orientation.
Therefore, Inhibitors,Modulators,Libraries the ADS40 requires integrated global positioning system (GPS) and inertial measurement unit (IMU) data for direct orientation support [11].The DMC and UltraCam systems utilize frame (area) CCD arrays, Inhibitors,Modulators,Libraries and collect imagery in a manner similar to film-based cameras with unique camera stations per frame. These digital cameras use multiple CCD arrays to create Inhibitors,Modulators,Libraries individual Inhibitors,Modulators,Libraries large format image frames [11-13]. Multispectral data are acquired at a coarser spatial resolution than the panchromatic, and pan-sharpening is employed to create the Inhibitors,Modulators,Libraries final high resolution multispectral images [11,14].2.?Study AreasCustom demonstration data sets were acquired at two locations.
A study area near Tecate, Inhibitors,Modulators,Libraries CA was selected as the primary area for the evaluation.
Tecate is a small town along the U.S./Mexico border that is located 40 km east of the Pacific Ocean. Brefeldin_A DMC and UltraCam-D AV-951 imagery was compound libraries acquired for this location. The 6.1 km by 1.9 km Tecate study area is characterized by terrain varying from gentle to extreme, with Mediterranean-type vegetation including natural moreover grass, coastal sage scrub, and chaparral.ADS40 imagery was not collected at the Tecate, CA area due to logistical constraints.