background: the heterogeneous composition of the human body presents numerous tissue types and cavities with widely differing radiologic properties. the aim of the present work was to develop a low cost homogeneous and heterogeneous phantom and the absorbed dose were measured by ionization chamber for different radiotherapy treatment techniques and compared with treatment planning system absorb...

In general, growth characterises the process by which a material increases in size by the addition of mass. In dependence on the prevailing boundary conditions growth occurs in different, often complex ways. However, in this paper we aim to develop a model for biological systems growing in an inhomogeneous manner thereby generating residual stresses even when growth rates and material propertie...

Abstract The occurrence of fingered preferential flow depends on both flow and porous media characteristics. The boundary condition of unsaturated infiltration has been investigated to assess whether it produces unstable wetting in homogeneous coarse sands. Laboratory tracer experiments were conducted in two coarse sand materials; for each sand material two initial conditions of air dry and fie...

In this memo, we review the three basic schemes of obtaining low spatial frequency data for millimeter array observations: (1) use of a large single dish, (2) interferometry with a multi-size array, and (3) scanning with a homogeneous array. We describe an application of the homogeneous array concept using the three antenna Hat Creek array. In an appendix, we analyze the eeects of random, uncor...

In this memo, we review the three basic schemes of obtaining low spatial frequency data for millimeter array observations: (1) use of a large single dish, (2) interferometry with a multi-size array, and (3) scanning with a homogeneous array. We describe an application of the homogeneous array concept using the three antenna Hat Creek array. In an appendix, we analyze the eeects of random, uncor...

By virtue of a complete set of two displacement potentials, an analytical derivation of the elastostatic Green’s functions of an exponentially graded transversely isotropic bi-material full-space was presented. Three-dimensional point-load Green’s functions for stresses and displacements were given in line-integral representations. The formulation included a complete set of transformed stress-p...

With their potential for spectacular applications, like superlensing and cloaking, metamaterials are a powerful class of nanostructured materials. All these applications rely on the metamaterials acting as a homogeneous material. We investigate a negative index metamaterial with a phase-sensitive near-field microscope and measure the optical phase as a function of distance. Close to the metamat...