โ Scribed by D.A. Ratkowsky
No coin nor oath required. For personal study only.
Five equations, viz. the Bacon, Bragg, Ergun, Lorentz and Ruland equations, for describing the preferred orientation of graphite-like materials were studied in combination with eleven sets of data using modem techniques for examining the behaviour of nonlinear regression models. The Bragg equation, which is based upon the normal (Gaussian) probability distribution, had the best statistical properties, in that the estimators of the parameters of the equation were close to being unbiased, normally dist~buted, minimum variance estimators. The other four equations were generally more erratic in their statistical behaviour, their estimators being highly biased and skewed in their distribution for at least one data set. The Bragg equation was generally the best fitting model, with the Lorentz and Ruland equations being generally the worst fitting models. The Bragg equation can therefore be recommended for general use to describe the preferred orientation of graphitic materials.
๐ SIMILAR VOLUMES