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
Woman in Blue Reading a Letter the quotidian, private moment becomes revealing of the human condition. The painting is unique among Vermeer's interiors in that no fragment of corner, wall or ceiling can be seen. Woman in Blue Reading a Letter Woman Reading a Letter () is a painting by the Dutch painter Johannes Vermeer. Part of the collection of the City of Amsterdam as part of the Van der Hoop bequest, it has been in the Rijksmuseum since its inception, and was thus the first Vermeer they acquired. The central element of the painting is a woman in blue standing in front of a window