This makes Coinbase useless for day traders and bots, which rely on the ability to trade back and forth many times per hour. (bitcoinmagazine.com)
By adjusting elements of the test, such as the air exchange rate, which is the number of times per hour indoor air is replaced by outdoor air, as well as the concentrations of terpene and ozone in the chamber, the group was able to ascertain how those variables each affected the formation of secondary organic aerosols. (sciencedaily.com)
There are a bunch of these; I use underlining a lot, and I write notes several times per hour of reading, and I use user - supplied documents and public domain books a lot on my Kindle. (dealsagar.com)