{'fraction_non_alphanumeric': 0.022082018927444796, 'fraction_numerical': 0.004206098843322818, 'mean_word_length': 5.6573426573426575, '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}}
Analysis of high-frequency thermal phenomena with a commercial imaging radiometer

We have developed a system which allows repetitive thermal events at frequencies as high as 2 kHz to be imaged without aliasing. A prototype unit, consisting of an unmodified scanning imaging radiometer (Inframetrics IR-600) , a PC-AT compatible microcomputer, and specially developed interface hardware and software, has been built and tested. The system functions as a video lock-in amplifier in that temperature components of the scene which vary at a preselected frequency are amplified, while other frequency components of the target temperature average out over time. Several applications of the system are discussed, including applications to engine research, nondestructive evaluation of materials, and feature extraction in high clutter environments. The tradeoffs between temporal resolution, spatial resolution, and image acquisition time are also examined.