The present invention relates to a method for graphically displaying a sectional image of an object under examination having objects situated therein, in particular for the display of a sectional image of a building wall. A drying channel is defined between the two chambers and material to be dried passes along the channel. This movement may be, in turn, transferred to a motor through, for example, a rack and pinion gear, to convert the mechanical movement to electrical energy. A return result from the service node is provided, based on the decision of what action is to be taken with respect to the service request, to the first entity which then determines how the action is to be effectuated.