Abstract: The data transmission device (2) of the present invention comprises a data dividing section (212) for dividing data to be transmitted into a plurality of divided data pieces; an identification information assignment section (213) for associating identification information for identifying the plurality of divided data pieces with each of the plurality of divided data pieces; and a data processing section (214) for assigning a group of data processing for the plurality of divided data to any of a plurality of threads (211) capable of parallel processing to be executed, wherein the group of data processing includes: a transmission data preparation process of compressing specified divided data pieces among the plurality of divided data pieces and preparing a plurality of transmission data pieces associated with the identification information.

Abstract: A magnetic screw device comprising an internal (male) magnetic screw having the even number of magnetized bands spirally magnetized on an outer surface with contiguous magnetized bands having opposite polarities and an external (female) magnetic screw having the even number of magnetized bands spirally magnetized on the same outer surface with contiguous magnetized bands having opposite polarities. The internal and external magnetic screws are composed of a plurality of spiral cylindrical magnets disposed in its axis direction, the spiral cylindrical magnet being formed of short cylindrical permanent magnet materials on each outer or inner surface which is spirally magnetized. The internal magnetic screw includes a rod member to support the inner spiral cylindrical magnets.