Methods and devices are provided for delivery an orthopedic, e. More particularly, networks and systems are provided for gathering remotely sensed profiles of the meteorological conditions and for building the meteorological model. Two housing halves are connected to the base by one or more hinges. The first limb, the second limb and the third limb include a volume for the respiratory gas and which volume includes both an active volume with the gas exchanging between the inspiratory phase and the expiratory phase and a dead volume for the respiratory gas with insufficient gas exchange from the inspiratory phase to the expiratory phase and the dead volume being less than 1 ml. The two-beam interference signals may be created by reflecting light off the two surfaces of the optical structure.