The present invention discloses an image splicing method and apparatus, and relates to the field of image processing technologies. The reduced iron discharger involves minimal structural waste, and gives a satisfactory yield. Mechanical means is also disclosed whereby the elevator car doors may only be forced opened a limited amount if the car is stalled between landing sites. An entry is added to a linked list that is used to track valid data stored at the persistence storage device and then the data is transferred from the persistence storage device to the storage device of the storage system. The path can be determined by mathematical integration of the tangential vector or by double mathematical integration of the tangential acceleration which can be determined for example by the scalar product of a tangential unitary vector obtained by normalization of the tangential vector and of data representative of the acceleration supplied by the accelerometer.