The problem of neutrino mass hierarchy may be solved using such future underice and underwater megaton-scale detectors as PINGU and ORCA. In my lectures I plan to present the basic ideas concerning neutrino properties and their manifestations in these experiments and to discuss the role of an accurate account for the neutrino-nucleon cross-sections at energies from 5 GeV to 100 GeV. The basic ideas and uncertainties in calculations both at low and at extremely high energies will be discussed.
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Askhat Gazizov
Institute of Physics of the NASB, Minsk, Belarus

in collaboration with M. Kowalski (DESY-Zeuthen), K. S. Kuzmin (JINR),
V. Naumov (JINR) and Ch. Spiering (DESY-Zeuthen)