{'fraction_non_alphanumeric': 0.03572984749455338, 'fraction_numerical': 0.036601307189542485, 'mean_word_length': 5.222222222222222, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
COMPARISON OF SPACEBORNE AND AIRBORNE HYPERSPECTRAL IMAGING SYSTEMS FOR ENVIRONMENTAL MAPPING

The main purpose of this study was to compare hyperspectral remotely sensed data collected by the Hyperion satellite, and the airborne Real-time Data Acquisition Camera System (RDACS-3) and the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) for environmental mapping and vegetation species identification. Hyperion was NASA's first hyperspectral imager aboard NASA's Earth Observing-1 (EO-1) spacecraft. The EO-1 mission had three advanced land imaging instruments; Advanced Land Imager, Hyperion, and Atmospheric Corrector. AVIRIS collects 224 contiguous spectral bands with wavelengths from 0.4 to 2.5 μm, whereas RDACS-3 has many spectral modes (64, 128, 256, etc.). The study area, Land-Between-the-Lakes (LBL), is located in western Kentucky, USA. Most of LBL consists of forested areas, which are predominantly oak and hickory, and open land areas. Twenty-five percent (17200 hectares) of LBL falls within the Biosphere Reserve. AVIRIS was flown on the Twin Otter turboprop at approximately 4000m above the ground with 4m spatial resolution on November 11, 1999 and September 10, 2001. The Hyperion provided 242 spectral bands (from 0.4 to 2.5 μm) with a 30 meter spatial resolution and covered 7.5km by 200km area on April 29, 2001. An RDACS-3 imagery with 120 spectral bands and 2x4m spatial resolution was collected at 2350m above the ground by the ITD Spectral Visions on September 7, 1999. During the overflights, ground spectra using an ASD FieldSpec-FR spectroradiometer (0.35-2.5 μm) were collected for data calibration, spectral library construction, atmospheric correction and species identification. Moreover, multispectral satellite and aerial imagery at 1m resolution was collected for some of the test sites in the area. Several hyperspectral and multispectral processing tools were utilized for atmospheric corrections, enhancements, and classifications. Best results were obtained using the AVIRIS and RDACS-3 data. The Hyperion data also provided very good results for the mapping; however, its spatial resolution was one of the limitations of the Hyperion sensor. The statistical difference among the classifications using the sensors proved to be mostly significant.