organised by Sira Institute Ltd. as one of its OPTECH '78 events. organised by Sira Institute ; editor, W. D. Lawson. organized by Sira Institute ; editor, T. L. Williams. organised by Sira Institute Limited ; L.R. Baker, K.J. Rosenbruch, editors. organised by Sira Institute Limited. organised by The Institution of Engineers. organised by the Institution of Chemical Engineers. organised by the Institution of Electrical Engineers. organized by The Institute of Civil Engineers.