Metal crack size recognizing used circular patch antennaHanalde Andre, Teguh Putra Trila Seyepa, Amirul Luthfi, Ridho Aidil Fitrah, Toha Zaky and Rizda Azri RamleeE3S Web Conf., 464 (2023) 01017DOI: https://doi.org/10.1051/e3sconf/202346401017