A cable tension device includes a fixing seat, a rotation shaft, a ratchet unit, a movable seat, a safety locking plate, a control member, an engaging board, a push board, a compression spring, and a tension adjustment knob. The second plate can slide with respect to the first plate and preferably slides along the surface of the main unit to cause the first and second key sections of the main unit to be covered and exposed by the display unit. The meta-data is analyzed, using a processor of the computing device, to determine a context in which the visualization of the data will be used. The solvent used to dissolve the Group VI elements comprises octadecene. The protection lid couples to the second end portion of the fixing shaft to prevent lubricants for lubricating the bearing from splashing. The power transmission unit includes: a ground-side coil ; and a housing set on a ground and configured to house the ground-side coil.