A mathematical determination model is used to select odorants for products to be perfumed and for the preparation. Specifically, at least one stromal volume having a substantially conical shaped surface is photodisrupted. The core is preferably encapsulated with the material of the edge lining by injection molding in order to achieve an improved joining and the provision of a small gap between the core and the edge lining. On the occasion of input of a checkup instruction of the fuel cells, the drive controller causes the fuel cells to be driven in the flooding elimination mode, independently of the ambient temperature.