Researchers at the Georgia Institute of Technology have developed a system that encodes information onto chaos, transmits it, and then decodes the information away from the chaos. Rajarshi Roy, one of the researchers and chair of Georgia Tech's School of Physics, explains how it works. "In an ordinary digital signal, the message can immediately be seen," Roy reports. "But in our system, digital information is encoded in the chaos, so the message would not be obvious to a person who may intercept it." In the experimental system, a stable semiconductor diode laser produces a square wave "message" signal. That signal, amplified by an erbium-doped fiber amplifier (EDFA), is introduced into a chaotic signal produced by an erbium-doped fiber ring laser like that used in today's communications industry. The resulting combined signal, containing a mix of the message and chaotic carrier, moves through an optical fiber to a second EDFA nearly identical to the first. Upon encountering the combined signal, the receiving EDFA begins generating chaotic fluctuations synchronized with those produced by the transmitting laser. The chaotic portion of the signal, measured by a digital oscilloscope, is subtracted from the combined signal and low-pass filter to recover the original "coded" message. E-mail firstname.lastname@example.org.
Samsung's Galaxy line of smartphones used to fare quite well in the repairability department, but last year's flagship S5 model took a tumble, scoring a meh-inducing 5/10. Will the newly redesigned S6 lead us back into star-studded territory, or will we sink further into the depths of a repairability black hole?
In 2003, the world contained just over 500 million Internet-connected devices. By 2010, this figure had risen to 12.5 billion connected objects, almost six devices per individual with access to the Internet. Now, as we move into 2015, the number of connected 'things' is expected to reach 25 billion, ultimately edging toward 50 billion by the end of the decade.
NASA engineer Brian Trease studied abroad in Japan as a high school student and used to fold fast-food wrappers into cranes using origami techniques he learned in library books. Inspired by this, he began to imagine that origami could be applied to building spacecraft components, particularly solar panels that could one day send solar power from space to be used on earth.
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