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Search Publications by

Yusi Cao (Fed)

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Displaying 1 - 2 of 2

First measurements of the flux integral with the new NIST-4 watt balance

March 31, 2015
Darine El Haddad, Frank Seifert, Leon Chao, Yusi A. Cao, Georgio A. Sineriz, Jon R. Pratt, David B. Newell, Stephan Schlamminger
In early 2014, construction of a new watt balance, named NIST-4, has started at the National Institute of Standards and Technology (NIST). In a watt balance, similar to a mass comparator, the gravitational force of an unknown mass is compensated by an

Construction, Measurement, Shimming, and Performance of the NIST-4 Magnet System

June 6, 2014
Frank Seifert, Alireza Panna, Leon Chao, Bing Han, Shisong Li, Yusi A. Cao, Darine El Haddad, Stephan Schlamminger, Heeju Choi, Lori Haley
The magnet system is one of the key elements of a watt balance. For the new watt balance currently under construction at the National Institute of Standards and Technology a permanent magnet system was chosen. We describe the detailed construction of the