Abstract: Provided is a method of manufacturing a non-oriented electrical steel sheet, the method including first hot-rolling each of first and second steel materials containing silicon (Si), manganese (Mn), and aluminum (Al), forming a first laminated structure by laminating the first hot-rolled first and second steel materials, forming a second laminated structure by second hot-rolling the first laminated structure, forming a third laminated structure by cold-rolling the second laminated structure, and cold-annealing the third laminated structure.

Abstract: In order to inspect a board, first, a board prior to mounting an element on the board by a mounter is transferred to a work stage. Then, warpage of the board is inspected. Thereafter, in case that the board is judged good as a result of the inspection, the board is transferred to the mounter, and in case that the board is judged no good as the result of the inspection, the board is finally determined no good without transferring the board to the mounter. Thus, unnecessary works and defective products may be prevented beforehand, and productivity and efficiency of inspection may be increased.