this study aimed to modify the current purchase formula of sugar beet into a formula with different coefficients with respect to sugar percentage of autumn sugar beet. ahvaz sugar factory was selected as an autumn sowing factory in iran and 163 samples were randomly taken at different delivery times in 2007 (28th april to 27th june).  from each truck, one sample was taken and sugar content, wat...

introduction: land use in the overall concept is said to be the type of using land in the current situation which contains all users in different sectors of agriculture, natural resources and the industry. protecting land use is as follows: “prevent the change of application of certain lands by their owners, if their change has negative natural, economic, political, cultural, or scientific effe...

Care must be taken when interpreting the coefficients of dummy variables in semi-logarithmic regression models. Existing results in the literature provide the best unbiased estimator of the percentage change in the dependent variable, implied by the coefficient of a dummy variable, and of the variance of this estimator. We extend these results by establishing the exact sampling distribution of ...

in this paper, we apply the differential transform (dt) method for finding approximate solution of the system of linear and nonlinear volterra integro-differential equations with variable coefficients, especially of higher order. we also obtain an error bound for the approximate solution. since, in this method the coefficients of taylor series expansion of solution is obtained by a recurrence r...