Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Bryan C. Waltrip


Eddy Current Rail Inspection Using AC Bridge Techniques

Andrew D. Koffman, Bryan C. Waltrip, Yicheng Wang
AC bridge techniques commonly used for precision impedance measurements have been adopted to develop an eddy current sensor for rail defect detection. By using

AC Power Standard Using a Programmable Josephson Voltage Standard

Bryan C. Waltrip, Bo Gong, Thomas L. Nelson, Yicheng Wang, Charles J. Burroughs, Alain Rufenacht, Samuel P. Benz, Paul D. Dresselhaus
This paper describes the implementation of a new quantum-based system for the generation of 120 V rms, 5 A rms, sinusoidal, active and reactive power over the
Created October 9, 2019