An algorithm to estimate reflection coefficient properties of materials based on code multipath errors is developed and tested in two urban environments. The algorithm extends an existing model that integrates 3D structure models, electromagnetic ray-tracing algorithms, antenna pattern measurements, and receiver tracking loop models to simulate code multipath errors. Instead of using the Fresne...

The problem of water wave scattering by a semi-infin ite floating dock on the free surface of an ocean with variable bottom topography is considered using linear theory. By employing a perturbation analysis and using Green's integral theorem, the analytical expression for the first order reflection coefficient is obtained in terms of a computable integral involving the bottom shape function. Al...

in this paper the reflection coefficient of electromagnetic wave incidence on the walls of the buildings and obstacles that occurs in mobile communication path was modified by solving the riccati nonlinear equations. for this purpose, the building walls are assumed inhomogeneous layers where their permittivity changes as function of the wall thickness. using this reflection coefficient, a new p...

This paper deals with a new formulation for the diffraction of a plane wave by a periodic grating. As a simple example, the diffraction of a transverse magnetic wave by a perfectly conductive periodic array of rectangular grooves is discussed. On the basis of a shadow hypothesis such that no diffraction takes place and only the reflection occurs with the reflection coefficient −1 at a low grazi...

We discuss the effect of a single diagonal defect on both the static and dynamical properties of entanglement in a spin chain. We show that entanglement localizes at the defect and discuss its localization length, arguing that this can be used as a mean to store entanglement. We also show that the impurity site can behave as an entanglement mirror and characterize the bouncing process in terms ...

The purpose of this paper is to provide a comprehensive review of how technology has been used to enhance or replace field experiences in preservice teacher preparation programs, and discuss the benefits and limitations of traditional and technology-enhanced/virtual field experience approaches. In this paper, three types of technology-enhanced field experiences are discussed: Type I concrete, d...

In the later part of the paper we shall assume in addition that p decays exponentially at −∞. The support properties of the potential imply that the right reflection coefficient r(k) admits a meromorphic continuation to the upper half-plane C+ = {k ∈ C, Im k > 0} with at most finitely many poles. The inverse problem under consideration consists of recovery of the potential p from the sequence {...

This study sought to determine if, how, and the extent to which, the implementation of lesson study with preservice teachers facilitates reflection in its participants. The lesson study reports of 20 preservice teachers were analyzed qualitatively along three dimensions to determine what lesson study reports revealed about their reflections. More specifically, the analysis sought to determine w...