A rotary power device of the swinging piston type has a cylindrical rotor mounted between internal and external portions of a stator. Information is recorded in the first group unit. The retaining piece comprises a cupular guide piece and a sleeve piece, which may be inserted in and rotated in the cupular guide piece against the force of a spring. The precipitate is separated from said water and the water is desalinated using reverse osmosis, flash evaporation, or another method. Using forecasting techniques enables business managers to predict the likelihood of achieving a particular goal without relying on manual analysis by a skilled analyst. A memory device according to one embodiment includes a plurality of memory blocks having finite endurance andor retention, at least one of the blocks having monitor data written therein; and circuitry for addressing the blocks.