in this research work, the parameters affecting the settling velocity within the thickeners were studied by introducing an equivalent shape factor. several thickener feed samples of different densities including copper, lead and zinc, and coal were prepared. the settling tests were performed on the samples, and the corresponding settling curves were plotted. using the linear regression analysis...

carbon sequestration into plants biomass, especially in fast growing trees is an easier and economically way for dropping off co2 from atmosphere. this study was carried out in order to investigate above-ground biomass of white poplar (populous alba, l.) plantations that was planted in fourdifferent plant spacing (0.5 × 0.5, 1×1, 2×2 and 4×4 m.) in chaharmahal and bakhtiari province in west of ...

This paper presents an empirical investigation of the critical determinants for the adoption of e-market in Australian small-and-medium sized enterprises (SMEs) within the technology-organization-environment (TOE) framework. A conceptual model is proposed for better understanding the adoption of e-market in Australian SMEs. Structural equation modelling is used for testing and validating the co...

In a hierarchical or fixed-order regression analysis, the independent variables are entered into the regression equation in a prespecified order. Such an analysis is often performed when the extra amount of variance accounted for in a dependent variable by a specific independent variable is the main focus of interest (e.g., Cohen & Cohen, 1983). For example, in the area of reading achievement, ...

Multilevel modeling in general concerns models for relationships between variables defined at different levels of a hierarchical data set, which is often viewed as a multistage sample from a hierarchically structured population. Common applications are individuals within groups, repeated measures within individuals, longitudinal modeling, and cluster randomized trials. This chapter treats the m...