“…Development of com yield models has been attempted by several researchers (Childs et al, 1977;Corsi and Shaw, 1971;Curry, 1969;Curry and Chen, 1969;Duncan et al, 1967;Newman et al, 1968;Parsons and Holtman, 1976;Stapleton, 1970). The performance of this arrangement has been tested by several researchers (Gustafson et al, 1976;Otten and Brown, 1982;Morey et al, 1976aMorey et al, , 1981.…”