{'fraction_non_alphanumeric': 0.017985611510791366, 'fraction_numerical': 0.0, 'mean_word_length': 5.054347826086956, '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}}
Controlling the breakup of spiral waves in an excitable medium by applying time-delay feedback signals

The spiral-wave breakup to turbulence in an excitable medium, starting from the spiral-wave center via Doppler instability, is controlled by modulating a local region around the spiral-wave center. The modulation signal is extracted from the controlled region with a certain time delay. By injecting a feedback signal with very low intensity into a very small space area, we can successfully stabilize the spiral wave and prevent breakup to turbulence.