Circle diagram constant air-gap induction motor images shown here, where, The circle diagram is drawn using the data obtained from no load and either short circuit or, in case of machines, blocked rotor tests by fitting a half-circle in points O and A. Beyond the error inherent in the constant air-gap assumption, the circle diagram introduces errors due to rotor reactance and rotor resistance variations caused by magnetic saturation and rotor frequency over the range from no-load to operating speed. Steinmetz equivalent circuit Circle diagram First conceived by A. Heyland in 1894 and B.A. Behrend in 1895, the circle diagram is the
What Is a Nation? What Is a Nation? "What is a Nation?" ("Qu'est-ce qu'une nation?") is an 1882 lecture by French historian Ernest Renan (1823–1892), known for the statements that a nation is "a daily referendum", and that nations are based as much on what the people jointly forget, as what they remember. It is frequently quoted or anthologized in works of history or political science pertaining to nationalism and national identity. Renan wrote "What is a Nation" in order to symbolize the nationalism which was born in France as a result of the French Revolution of 1789. Renan begins his essay by noting