This paper presents a new design of dual band RFID reader antenna for ISM-band industrial science and medical applications at 2.4 GHz 5.8 GHz. Theantenna is designed physically built using FR4 substrate taking 1.5 thickness, 4.3 relative permittivity 0.025 loss tangents. Different slots havebeen introduced to reduce the dimensions achieve bandfor microwave ISM application. The dimension propose...

abstract variation of climatic elements could be estimated by standard deviation, coefficients of variation and so on. in iranian climatological literature, variations of climatic elements have main attention during last decades. meanwhile worldwide climatologist desired to study the characteristics of variations as well as the distribution of frequency average of these elements. in this paper,...

Transformation optics offers an unconventional strategy to the design of metamaterial devices. In this letter, we propose a class of optical transformation media, illusion media, which can render the enclosed object invisible and generate one or more virtual objects as desired. An arbitrary object enclosed by such an illusion medium layer appears to be one or more other objects. We apply the pr...

We consider the scattering of time harmonic electromagnetic plane waves by a bounded, inhomogeneous dielectric medium that is partially coated by a thin metallic layer in R. We use far field pattern of the scattered waves at a fixed frequency as data to determine the support D of the inhomogeneous obstacle, the surface conductivity that characterizes the coating and the relative permittivity. N...

We theoretically studied how to directly engineer the constitutive parameters of metamaterials for perfect absorbers of electromagnetic waves. As an example, we numerically investigated the necessary refractive index n and extinction coefficient k and the relative permittivity ε and permeability μ of a metamaterial anti-reflection layer, which could cancel the reflection from a hydrogenated amo...

in this paper, a new propagation model based on utd for multiple diffraction paths in cellular mobile radio communications in urban environments is proposed. moreover, the most rigorous novel utd-based expressions for multiple diffractions by buildings and excess path losses are d - rived and analyzed. for this purpose, building rows are supposed to have rectangular cross-sections with the same...

responses of twenty chickpea genotypes to drought stress were evaluated in the farm of college of agricultutre, razi university, kermanshah, iran in 2006-2007. the experiment was carried out in randomized complete block design with three replications under two water stress and non-stress conditions. the results showed significant differences among the genotypes for most of the traits. maximum y...