Abstract: A roof side bar is configured for prevention of noise for an automobile. The roof side bar includes a cross bar mounting hole to which a cross bar may be mounted, and/or an interior space having a specific volume located behind the cross bar mounting hole, wherein a partitioning wall may be provided to divide the interior space into a plurality of subspaces so as to vary a resonant frequency in the interior space.

Abstract: A roof side bar is configured for prevention of noise for an automobile. The roof side bar includes a cross bar mounting hole to which a cross bar may be mounted, and/or an interior space having a specific volume located behind the cross bar mounting hole, wherein a partitioning wall may be provided to divide the interior space into a plurality of subspaces so as to vary a resonant frequency in the interior space.

Abstract: A watermarking method is provided. The method includes: the steps of creating an entire watermark for an image frame by using a secret key; dividing an image frame of the digital image file into divided frames by at least one row and at least one column; applying a predetermined watermark creating algorithm to pixel data of each divided frame to generate a unit watermark; and applying the unit watermarks with the digital image file. The step of creating the unit watermark uses a public key or applies a keyless algorithm. Another watermarking method includes the steps of dividing the image frame into a plurality of divided frames, each divided frame partially overlapping neighboring divided frames; applying a predetermined watermark creating algorithm to pixel data of each divided frame to generate a unit watermark; and applying the unit watermarks with the digital image file.