منابع مشابه
Squabble continues over cancellation of HIV vaccine facility.
Rarely do governments set aside a huge chunk of money for a scientific project and run a complex, three-year competition to select a winner, only to yank the funds off the table at the last minute, ostensibly on the grounds that there was no need for the initiative in the first place. At the very least, it’s considered bad form to have wasted the research community’s time and effort. Yet, such ...
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A friction-variable touch panel is capable of presenting virtual bumps and holes on its flat surface through the control of the surface frictionwhen a fingertip slides over it. To improve thepresentation, we developed a friction model of a fingertip sliding over a sinusoidal surface with an amplitude of 0.5–2.5mm and a spatial wavelength of 20–50mm. When a metal ball rolls over a wavy surface w...
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ژورنال
عنوان ژورنال: Nature
سال: 1991
ISSN: 0028-0836,1476-4687
DOI: 10.1038/351594b0