Assessment of the functional behaviour of precision engineering workers using ultradian rhythms of HRV indicators in the prevention of man-made disastersAnastasia Bashkireva, Tatiana Bashkireva, Alexander Severin, Evgeniya Severina and Gazi HalabE3S Web Conf., 474 (2024) 01033DOI: https://doi.org/10.1051/e3sconf/202447401033