Circle diagram Circle diagram First conceived by A. Heyland in 1894 and B.A. Behrend in 1895, the circle diagram is the graphical representation of the performance of the electrical machine drawn in terms of the locus of the machine's input voltage and current. The circle diagram can be drawn for alternators, synchronous motors, transformers, induction motors. The Heyland diagram is an approximate representation of circle diagram applied to induction motors, which assumes that stator input voltage, rotor resistance and rotor reactance are constant and stator resistance and core loss are zero. Another common circle diagram form is as described in the two
Ida Reading a Letter Ida Reading a Letter Ida Reading a Letter is an 1899 painting by Vilhelm Hammershøi. It is an example of a work inspired by Dutch Golden Age painting and is currently in a private collection. In 1887 Hammershoi travelled to the Netherlands, where he saw works by Vermeer and his Delft contemporaries first-hand. This painting shows many characteristics of such room interiors, usually featuring a woman at an everyday task. This painting seems to have been directly inspired by a Vermeer he would have seen in Amsterdam, "Woman in Blue Reading a Letter". The use of the hairstyle, pose, table