El Sol Esta En Tus Ojos Ieee

10 000 megawatts

Shortfall in the Japanese electricity grid three days after the 11 march earthquake. Officials said power plants in western Japan could do little to help the stricken east.The Sun’s in Your Eyes

A solar-powered sensor could monitor the eyeball’s pressure

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n the future, that twinkle in your loved one’s eye might be an implanted solar-powered pressure monitor. Atthe 2011 IEEE International Solid-State Circuits Conference in February, engineers from the University of Michigan, in Ann Arbor, described their work on a cubic-millimetersize sensor meant tomonitor pressure inside the eye. The researchers have yet to test the device in human eyes or animal ones, but they hope their system will one day thwart optic nerve damage brought on by glaucoma. Todetermine a glaucoma patient’s treatment, doctors must monitor pressure inside the eye, says Gregory Chen, a graduate student of electrical engineering at Michigan. Today’s methods gauge that pressure bypushing on the cornea, the eye’s clear outer coating. The results may be inaccurate: “If you just happen to have a really thick cornea, your eye is going to be harder, no matter what the pressureis,” Chen says. The engineers’ prototype device would allow a microelectromechanical systems (MEMS) capacitive sensor to record pressure from inside the eye about every 15 minutes and store it tostatic RAM. Once a day, the system would wirelessly transmit the day’s data, via
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two on-chip inductors, to a wand. The inductors would send the data at both 400and 900-megahertz carrierfrequencies, as a means of mitigating the signal’s noise and increasing its range. Powering this daily transmission was one of the team’s biggest challenges, says Mohammad Hassan Ghaed, the Michigan gradstudent who designed the radio system. “The common way of transmitting data is to use an external antenna,” he says, “but in this millimeter-cubed space, we don’t have that luxury.” The team designed the...