4 research outputs found
Reconstruction of sub-threshold events of cosmic-ray radio detectors using an autoencoder
Radio detection of air showers produced by ultra-high energy cosmic rays is a cost-effective technique for the next generation of sparse arrays. The performance of this technique strongly depends on the environmental background, which has different constituents, namely anthropogenic radio frequency interferences, synchrotron galactic radiation and others. These components have recognizable features, which can help for background suppression. A powerful method for handling this is the application of convolution neural networks with a specific architecture called autoencoder. By suppressing unwanted signatures, the autoencoder keeps the signal-like ones. We have successfully developed and trained an autoencoder, which is now applied to the data from Tunka-Rex. We show the procedures of the training and optimization of the network including benchmarks of different architectures. Using the autoencoder, we improved the standard analysis of Tunka-Rex in order to lower the threshold of the detection. This enables the reconstructing of sub-threshold events with energies lower than 0.1 EeV with satisfactory angular and energy resolutions
Pulmonary embolism in multifield hospital: results of autopsy study
OBJECTIVE. Modern data analysis of the rate of pulmonary embolism (PE) development was made. A comparative analysis of epidemiology dynamics of diseases was carried out and included of the past 40 years. MATERIAL AND METHODS. The retrospective analysis of 2042 autopsies was conducted in autopsy department of Municipal clinical hospital â„–1 named after N. I. Pirogov at the period from 2011 to 2013. According to results of necropsies, 440 samples of pulmonary embolism of different localization and their terms were found. RESULTS. Conducted study demonstrated a relative growth of the development rate of pulmonary embolism and fatal pulmonary embolism. Pulmonary embolism had been revealed by autopsy in 4,4 % patients in 1964-1973, but the rate of PE increased to 21,5 % in 2011-2013. The fatal PE was noted in 9,3 % of autopsies in 2011-2013, though it counted 2,5 % in 1964- 1973. CONCLUSIONS. The rate of pulmonary embolism development increased in 5 times. The growth of the PE rate was revealed in postoperative period and significant part of complications (18,5 %) were associated with fatal PE