The rear unit comprises first and second doors for a motor vehicle. The pallet has a rectangular base and support members fixed to opposite edges of the base. Conversely, the piezo-sensing element may operate as a piezo-resistive tangential element when a constant current is conducted through the element in the tangential direction to the edge of the diaphragm. The keyword searcher is configured to receive the list of keywords and a textual string corresponding to the target document file, and search the textual string for instances of the keywords so as to generate a sequence of keyword instances.