Keyword: Noise

Briefs: Aerospace
Acoustic optimization for anti-phase asymmetric rotor.
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Briefs: Aerospace
The low-density, graphene-based aerogel could make aircraft as quiet as a hairdryer.
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Articles: Aerospace
Metamaterial printing, high-efficiency solar cells, and a noise-reduction material.
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Briefs: Transportation
Vibration-absorbing resonators could better soundproof walls and make vehicles more streamlined.
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NASA Spinoff: RF & Microwave Electronics
A NASA microphone that detects unseen air turbulence is lofted to high heights aboard a stratospheric glider.
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Articles: Test & Measurement
An R&D project indirectly leads to potentially greater power density, EV range, and battery life.
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Briefs: Wearables
The app detects fluid behind the eardrum using a piece of paper and a smartphone’s microphone and speaker.
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Briefs: Sensors/Data Acquisition
Applications include monitoring of earthquakes and tsunamis as well as manmade infrasonic sources such as boats.
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Briefs: Manufacturing & Prototyping
A chip-based technology generates sound profiles with high resolution and intensity to make ultrasound therapy more effective and easier.
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Briefs: Aerospace
High-Fidelity Sonic Boom Propagation Tool
The sBOOMTraj software tool predicts and mitigates ground noise generated during supersonic flight.
5 Ws: Sensors/Data Acquisition
The smartwatch app identifies sounds that a user is interested in and sends a friendly buzz and information about the sound.
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Briefs: Motion Control
NASA's phase-locked rotors reduce noise.
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Briefs: Mechanical & Fluid Systems
This trailing edge flap device reduces noise without compromising cruise efficiency or landing lift and stall characteristics.
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Briefs: Aerospace
This technique lowers airstream noise generated at the side edges of deployed flaps, elevons, or slats.
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Articles: Wearables
Heartbeat-based biometrics, sonic-boom displays, and an artificial leaf.
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Briefs: Data Acquisition

Current laser interferometry pressure pulse detection techniques use the shock-induced change in index of refraction to track detonation and/or shock fronts in a single fiber optic by reflecting laser...

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Briefs: Mechanical & Fluid Systems
This technology has applications in sonar, range measuring, directional-force sensors, flow meters, and vibration/noise sensing and control.
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Briefs: Materials

In the wake of recent developments that have reduced fan and jet noise contributions to overall jet-engine noise, aircraft designers are turning their attention toward reducing engine core...

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Briefs: Aerospace

NASA’s Langley Research Center has developed a new aircraft design with the engine nacelle over the wing, improving engine ground clearance and freeing landing gear design. While...

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Facility Focus: Medical

In October 1962, the U.S. Army Aeromedical Research Unit was established with a goal of providing specialized medical and physiological support to help close the gap between Army...

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Briefs: Aerospace

NASA Langley Research Center has developed a new approach for designing aircraft liner cores for noise reduction. The cores are comprised of multiple honeycomb-shaped chambers,...

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Briefs: Data Acquisition
Device for Providing Real-Time Rotorcraft Noise Abatement Information

Rotorcraft typically operate near the ground throughout the duration of the operation. For this reason, military rotorcraft are vulnerable to acoustic detection, and public acceptance of civil rotorcraft is limited by annoyance caused by rotor noise radiation. The purpose of...

Briefs: Electronics & Computers

Many applications require detection of both very small and very large signals. High-gain detector amplifiers provide low noise, but are easily swamped by large signals. Logarithmic amplifiers provide a...

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Briefs: Sensors/Data Acquisition
A Robust Waveguide Millimeter-Wave Noise Source

A noise source is an enabling technology for passive millimeter-wave remote sensing applications such as atmospheric sounding, and precipitation and ice cloud measurements. NASA Goddard Space Flight Center has developed a packaged noise source that will allow calibration of the front end at the...

Briefs: Materials

Researchers at NASA’s Glenn and Langley Research Centers have developed a groundbreaking bio-mimicking acoustic liner for quieting noisy environments. Conventional approaches have not been able to absorb...

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Briefs: Communications

Microphones, from those in smartphones to hearing aids, are built specifically to hear the human voice — humans can’t hear at levels higher than 20 kHz, and microphones max out at...

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Briefs: Aerospace

NASA’s Langley Research Center has developed a landing gear cavity modification that reduces noise produced during aircraft approach and landing. The modification is an innovative stretchable...

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Briefs: Test & Measurement

Time of flight is an approach that gauges distance by measuring the time it takes light projected into a scene to bounce back to a sensor. In time-of-flight imaging, a short burst of light is fired...

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Briefs: Electronics & Computers

A new approach was developed that overcomes the limitation of conventional chip-testing methods on 3D chips, which include many thin horizontal “floors” connected to one another by vertical...

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