  Considering von Neumann expression for reduced density matrix as
thermodynamic entropy of a system strongly coupled to baths, we use
nonequilibrium Green's function (NEGF) techniques to derive bath and energy
resolved expressions for entropy, entropy production, and information flows.
The consideration is consistent with dynamic (quantum transport) description
and expressions reduce to expected forms in limiting cases of weak coupling or
steady-state. Formulation of the flows in terms of only system degrees freedom
is convenient for simulation of thermodynamic characteristics of open
nonequilibrium quantum systems. We utilize standard NEGF for derivations in
noninteracting systems, Hubbard NEGF is used for interacting systems.
Theoretical derivations are illustrated with numerical simulations within
generic junction models.
