Posts Tagged ‘dynamics’
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Studies suggest that questions about recent activities are easy for legitimate users to answer but harder for potential intruders to find or guess, computer scientists Danfeng Yao explains. “We want the question to be dynamic. The questions you get today will be different from the ones you would get tomorrow.”
RUTGERS (US)—The trouble with most online security questions is that they’re not very secure, according to Danfeng Yao. Continue…
Monday, November 16, 2009 18:20 - 2 Comments
Science & Technology - Aug 21, 2009 11:19 - 0 Comments
‘Supercool’ atoms try to act like electrons
These three false-color images, from left, depict the density of cesium atoms in a superfluid (conducting) state, in a transition state and finally in an insulating state. The original sample consisted of a single-layer of cesium atoms that formed a sheet measuring 80 microns in diameter, barely visible to the naked eye. Green indicates the lowest density of atoms. Red indicates a high, constant density. Physicists call this a plateau, which a team of scientists have observed for the first time. (Courtesy: Nathan Gemelke and Cheng Chin/University of Chicago)
