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How Loud Are Your Mac's Fans?

When they get hot, Macs turn on various internal fans to keep components cool. The noise can be annoying, but just how loud is it? If you have an iOS device with a built-in microphone, you can download one of many free sound meter apps (search on decibel in the App Store) and see if you're subjecting your ears to a truly unreasonable noise level.

 

 

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Researcher Finds Some Copiers Can Alter Scanned Numbers

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According to a report from German computer scientist D. Kriesel, some Xerox WorkCentre copiers and scanners may alter numbers that appear in scanned documents. Having analyzed the output of two such devices, the Xerox WorkCentre 7535 and 7556, Kriesel found that “patches of the pixel data are randomly replaced in a very subtle and dangerous way”: in particular, some numbers appearing in a document may be replaced by other numbers when it is scanned. These substitutions can be particularly troublesome for documents such as invoices, construction plans, and medical information. Kriesel suspects that the problem may be related to the JBIG2 compression algorithm employed during scanning, which can substitute one scanned region for other scanned regions that are visually similar. So far, no fix has been reported.favicon follow link