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Akobuije Chijioke (Fed)

Publications

Progress in the Kibble Dynamic Force Reference

Author(s)
Jared Strait, Akobuije Chijioke
We present progress in the development of a dynamic force reference instrument (KDFR) based on the Kibble principle. We describe the operating principle and

Dynamic Calibration of Instrumented Charpy Strikers

Author(s)
Akobuije Chijioke, Nicholas Vlajic, Enrico Lucon
Charpy V-notch testing of metallic materials involves application of kilonewton-range force pulses on millisecond time scales, generated by impacting the

Primary Sound Standard Based On Dynamic Fabry Perot Interferometry

Author(s)
Akobuije Chijioke, Richard A. Allen, Steven E. Fick, Benjamin Reschovsky, Jared Strait, Randall P. Wagner
We describe an optical sound standard in which the sound pressure is measured by using a high-finesse optical cavity to observe the induced change in the
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Patents (2018-Present)

Calibration Apparatus And Calibrating A Laser Doppler Vibrometer Thumbnail

Calibration Apparatus And Calibrating A Laser Doppler Vibrometer

NIST Inventors
Michael Gaitan , Benjamin Reschovsky and Akobuije Chijioke
A new approach to characterize the performance of a laser Doppler vibrometer (LDV). The method uses two acousto-optic modulators to frequency shift the light from an LDV by a known quantity to create a synthetic velocity shift that is traceable to a frequency reference. Results are presented for

Sound Pressure Metrology Instrument And Determining Sound Pressure From Index Of Refraction

NIST Inventors
Richard A. Allen , Randall P Wagner , Benjamin Reschovsky and Akobuije Chijioke
A sound pressure metrology instrument determines sound pressure from index of refraction and includes: a light source that produces source light; the optical cavity that: receives an acoustic field from the sound source; receives the source light from the light source; produces acoustic-modified
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Created May 31, 2018, Updated December 8, 2022
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