A mathematical description is given of heat- and moisture-transfer processes in a pig house, for 880
weaned piglets, equipped with natural ventilation, AYoor heating and local air cooling by means of additional humidiAzcation. Dynamic discrete auto-regressive moving average (ARMA) models, describing the air temperature and humidity inside the building and continuous models as transfer functions are derived. Experiments were performed to identify the structure and coefficients of the discrete ARMA models, using recursive prediction error (maximum-likelihood and least-squares) methods. The input and output data for the identiAzcation experiments were collected from experiments carried out over
three seasons, viz., winter, spring and summer. The structure of the discrete models was established and it was found that the dynamic properties of the heat- and moisture- transfer processes could be described using Azrstorder dynamic models. The model orders were determined by AkaikeA