In a welding apparatus for the longitudinal seam welding of can bodies by way of electrode rollers, three drive stages, by means of which the wire electrode is driven in addition to the drive by the electrode rollers, are provided in the wire course. The present invention further provides polynucleotide and polypeptide sequence information stored on computer readable media, and computer-based systems and methods which facilitate its use. The detecting can further include transforming a heterogeneous software application into a homogeneous application. If so, a map of the severity of the natural event can be obtained from the sensor system database and compared to a database of infrastructure items.