Luminance distribution of Intermediate Sky

A new advanced system of daylight prediction has been developed and presented by the authors for the highest utilization of natural daylight and appropriate saving of the electrical power consumed by the artificial lighting in daytime. Though the research works for this system and for the Mean Sky upon which it is based have already been published4)∼11), one of the most essential parts of the research work, that is, the framing of the Intermediate Sky and its detailed contents have been only presented in a brief paper in Japanese.8) The Intermediate Sky was framed mainly from the current materials which had already been gathered by the authors before starting of the research work, as the measurement to be required for the establishment of the Intermediate Sky should be carried out for a very long time. The procedure of framing the Intermediate Sky and its results are stated in this paper.