抄録
The present mass standard based on the prototype of the kilogram has some serious problems such as surface contamination and unrecoverablity in the case of damage or loss. Research on monitoring and finally replacing the present mass standard are therefore encouraged and some approaches have been proposed. In this article, the superconducting magnetic levitation method, which is one of the approaches that also makes use of the unique properties of superconductivity, is reviewed together with a brief description about mass and electric standards.
