2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/112590Relation between natural nonequilibrium steady states of Ruelle and MacLennan-Zubarev ensembles is discussed for a system consisting of $M$ infinitely extended systems coupled with a small system. And a characterization of quasistatic processes is investigated for a small system coupled with a single reservoir.Mathematical Physicstext