摘要 |
A system for controlling an apparatus operating on a moving web, in accordance with a periodic characteristic of the web. Indicia of successive periods of the characteristics are generated and compared to generate control signals to the apparatus. Specifically, a cutoff control system for a web-fed printing press is disclosed wherein the effective position of the cutting apparatus along the web path is varied in accordance with variation in the position of a maximum density change in an individual repetitive image from that of a reference image, or in accordance with a cross-correlation between the individual image and a reference image.
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