Burr size models

Analysis of variance (ANOVA) for burr size models... 

In order to validate the developed burr size models, five sets of random experiments were performed within the ranges of the process parameters selected and the burr height and burr thickness values were measured. The experimental values were then compared with the predicted values of RSM-based models and it was found that these values were close to each other, as illustrated in Table 7.5. The maximum prediction... 

The multiple regression analysis was performed for constructing the RSM-based burr size mathematical models. In the present investigation, the second order burr height and burr thickness mathematical models have been developed in terms of four process parameters, namely, cutting speed (v) feed rate (/), drill diameter (d) and point angle (. The nonlinear second order response surface equation is given by ... 

The goodness of fit of the burr size mathematical models was also tested through the coefficient of determination (R ) and adjusted coefficient of determination (R adj) (Montgomery, 2003). The is the proportion of variation in the response explained by the regression model. In contrast, R dj is the coefficient of determination adjusted for the number of variables in the regression model. Unlike R, the R adj decrease if the variables are entered in the model that does not add drastically to the model fit. The coefficient of determination is given by (Montgomery, 2003) ... 

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