Three-dimensional integrable models based on modified tetrahedron equations and quantum dilogarithm

Simple solutions of modified tetrahedron equation are given. These solutions are related to the known solutions of the tetrahedron equation. Each R-matrix contains one (or two) “spectral” parameter(s). Using these simple solutions one gets two (resp. four) parameters commuting sets of two-layer transfer matrices, the whole number of parameters in each two-layer transfer matrix being five (resp. ten).