Retraction: Design of ultra low noise amplifier for noise measurement in inverter fault diagnosis

The IEICE Electronics Express Editorial Committee has concluded that the technical content, a large part of sentences, English expressions, and figures in this letter [1] are almost or completely identical as those in the previously published papers [2, 3]. We seriously consider this piracy-friendly problem. According to the ethic code of IEICE, we decided that it is appropriate to delete the paper [1] from IEICE Electronics Express. The ethic code of IEICE clearly states that the members of IEICE should avoid any suspicious behaviors violating copyrights. Design of ultra low noise amplifier for noise measurement in inverter fault diagnosis, " Ultra low-noise preamplifier for low-frequency noise measurements in electron devices, " IEEE Trans. Instrum.