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.
From home enthusiasts to workers on the manufacturing floor, everyone's imagination is captured by the potential of 3D printing. Prototyping, spare parts creation, art delivery, human organ creation, and even mass product production are all being targeted as current and potential uses for the technology.
Solar and wind energy are becoming more viable as a source of energy on the electric grid. For decades, the major drawback to solar and wind was that they’re temperamental. A cloudy day kills solar and a still day renders the wind turbines useless. Automation tools, however, are providing a path to help these renewables become practical.
In honor of Earth Day, the National Security Agency has launched the STEM Recycling Challenge in Maryland schools to encourage kids to think about where the garbage they throw out every day actually goes. The agency has also introduced “Dunk,” a muscular blue cartoon recycling bin wearing shorts and sneakers.
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?
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.