Engineering

Shape-memory alloys might help airplanes land without a peep

Having a home near a busy airport certainly has its perks. It is close to many establishments and alleviates the problem of wading through endless traffic to catch flights. But it does come at a cost—tolerating the jarring ...

Electronics & Semiconductors

Cutting through noise for better solar cells

As society moves towards a renewable energy future, it's crucial that solar panels convert light into electricity as efficiently as possible. Some state-of-the-art solar cells are close to the theoretical maximum of efficiency—and ...

Robotics

Teaching drones to hear screams from catastrophe victims

In a disaster, time is of the essence when searching for potential victims who may be difficult to find. Unmanned aerial vehicles make the perfect platform for state-of-the-art technology allowing emergency crews to find ...

Computer Sciences

Researchers use deep learning to 'denoise' nanopore data

Scientists from the Institute of Scientific and Industrial Research at Osaka University have used machine-learning methods to enhance the signal-to-noise ratio in data collected when tiny spheres are passed through microscopic ...

Consumer & Gadgets

Facebook customizes augmented reality to the flick of a wrist

Fresh off its recent augmented reality (AR) kick, Facebook Labs has revealed plans to curate this AI software for wearable devices. Projected as a shorter-term goal than the previously announced AR glasses, this wrist-based ...

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Noise

In common use, the word noise means any unwanted sound. In both analog and digital electronics, noise is random unwanted perturbation to a wanted signal; it is called noise as a generalisation of the acoustic noise ("static") heard when listening to a weak radio transmission with significant electrical noise. Signal noise is heard as acoustic noise if the signal is converted into sound (e.g., played through a loudspeaker); it manifests as "snow" on a television or video image. High noise levels can block, distort, change or interfere with the meaning of a message in human, animal and electronic communication.

In signal processing or computing it can be considered random unwanted data without meaning; that is, data that is not being used to transmit a signal, but is simply produced as an unwanted by-product of other activities. "Signal-to-noise ratio" is sometimes used to refer to the ratio of useful to irrelevant information in an exchange.

In biology, noise can describe the variability of a measurement around the mean, for example transcriptional noise describes the variability in gene activity between cells in a population.

In many cases, the special case of thermal noise arises, which sets a fundamental lower limit to what can be measured or signaled and is related to basic physical processes described by thermodynamics, some of which are expressible by simple formulae.

In some fields, noise means unwanted information or data that is not relevant to the hypothesis or theory being investigated or tested.

This text uses material from Wikipedia, licensed under CC BY-SA