Tre' Johnson spent nearly all of his career in Washington, and worked as a teacher in the Washington, D.C. area in retirement ...

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Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Gordon Scott has been an active investor and ...

Abstract: Efficiency maps (EffMs) illustrate the maximum efficiencies of electric machines over a range of torque-speed operating points. This article reviews the available techniques for efficiency ...