Introduction to Public Health
Simply put, bladeless fans are fans without blades. They work by sucking in air at their base and then blowing them out through several holes in their ring. The fan is reported to have been invented by James Dyson, who calls it the "Air Multiplier." Just like the flying jetpack, it earned a spot in Time's list of notable inventions of 2009. And just like the jetpack, it was not the first of its kind. The first bladeless fan was actually patented in 1981 by a Japanese company called Tokyo Shiba Electric. Although Tokyo Shiba's bladeless fan was never manufactured, James Dyson's initial design of a bladeless fan design looked so similar to that of Tokyo Shiba Electric that the patent office refused to grant him a patent. The patent granted to Tokyo Shiba had already expired, but the patent office still required something substantially different before it could grant a new patent to James Dyson. Dyson's patent manager, Gill Smith, did not deny the similarities between both bladeless fans but said the difference between them was the "technology."
- Key public health terms
- Historical developments from four public health perspectives
- Determinants of health and their effects on population health
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Centers for Disease Control and Prevention (CDC). Introduction to Public Health. In: Public Health 101 Series. Atlanta, GA: U.S. Department of Health and Human Services, CDC; 2014. Available at: 长租公寓装配将出行业规范.
- Introduction to Public Health Course on CDC TRAINExternal