A mathematical model is proposed for describing the temperature dependence of the photoluminescence spectrum of self-ordered arrays of quantum dots with due regard for the electron-phonon interaction and different transfer processes in the "quantum dot-wetting layer-barrier" system. This model, as applied to analysis of the experimental spectra of InAs quantum dots grown on GaAs vicinal substrates, makes it possible to separate the manifestations of different mechanisms of excitation transfer in the photoluminescence spectra and to relate the observed temperature dependences of the spectra to the structural features of the quantum-dot array.