Abstract: An apparatus for and a method of measuring permanent-magnet eddy-current loss is provided. A magnetic flux density measured in a Gaussmeter 60 is fed back to a control device 70, and thus operation of a power supply 80 is automatically controlled. Accordingly, an experiment can be efficiently conducted. A non-magnetic and non-conductive measurement jig 30 blocks heat generated in a permanent magnet sample from being dissipated to an iron core 10. Accordingly, eddy-current loss occurring in the permanent magnet sample 40 can be measured more precisely.

Abstract: Disclosed is a segmented magnet which may adjust the application direction of a heavy rare earth element for grain boundary diffusion depending on the magnetization direction of the segmented magnet so as to simplify the manufacturing process of the segmented magnet while reducing eddy current loss, and a method for manufacturing the same. The method includes preparing a plurality of permanent magnet parent bodies having a constant magnetization direction, diffusing a diffusion material into the prepared permanent magnet parent bodies via a pair of planes thereof opposite each other and parallel to the magnetization direction along grain boundaries so as to form a pair of diffusing surfaces, preparing a permanent magnet assembly by stacking the permanent magnet parent bodies in a line such that the diffusing surfaces thereof face each other, and segmenting the permanent magnet assembly into a plurality of pieces along planes perpendicular to the magnetization direction.

Abstract: A constant-current-drive LED module device includes a rectifier configured to receive and rectify an alternating current power source; a unidirectional LED module unit configured to connect to one end of the rectifier; and a constant current unit configured to connect between the unidirectional LED module unit and the other end of the rectifier to control constant current.

Abstract: A constant-current-drive LED module device includes a rectifier configured to receive and rectify an alternating current power source; a unidirectional LED module unit configured to connect to one end of the rectifier; and a constant current unit configured to connect between the unidirectional LED module unit and the other end of the rectifier to control constant current.