Aperture reflection coefficient of a parallel- plate waveguide by wedge diffraction analysis

Aperture reflection coefficient of parallel plate waveguide by wedge diffraction analysi

The Te-d1 mode reflection coefficient of a ground-plane mounted parallel-plate waveguide illuminating a reflecting sheet

Symmetric parallel plate waveguide reflection coefficient analyze

The influence of conducting flaps on the reflection coefficient of a parallel-plate waveguide illuminating a conducting sheet

Conducting flap effects on reflection coefficient of parallel-plate waveguide illuminating conducting shee

Radiation pattern of a ground-plane mounted parallel-plate waveguide analyzed by a surface integration technique

Surface integration analysis of radiation pattern of parallel plate waveguid

A new approach for shaping of dual-reflector antennas

The shaping of 2-D dual-reflector antenna systems to generate a prescribed distribution with uniform phase at the aperture of the second reflector is examined. This method is based on the geometrical nature of Cassegrain and Gregorian dual-reflector antennas. The method of syntheses satisfies the principles of geometrical optics which are the foundations of dual-reflector designs. Instead of setting up differential equations or heuristically designing the subreflector, a set of algebraic equations is formulated and solved numerically to obtain the desired surfaces. The caustics of the reflected rays from the subreflector can be obtained and examined. Several examples of 2-D dual-reflector shaping are shown to validate the study. Geometrical optics and physical optics are used to calculate the scattered fields from the reflectors

Children's rights in student voice projects:where does the power lie?

This paper aims to develop understandings around the factors which facilitate and those which constrain implementation of Article 12 of the United Nations Convention on the Rights of the Child (1989; UN General Assembly Resolution 44/25) in student voice projects. Article 12 is concerned with children being given the right to express their views freely, and for their views to be given due weight in matters affecting them. The paper considers empirical evidence from student voice projects in two schools in the south of England. Through examining the complex, micro-processes of school practices which came into play during the projects, it is argued that the power imbalance in student–teacher relationships plays a significant role in terms of inhibiting and enabling the implementation of Article 12. The paper draws on the work of Freire, Giroux and Foucault to help develop an understanding of the power differentials within student–teacher relationships

Application of wedge diffraction to antenna theory

Geometrical optics techniques for diffraction available for antenna analysi

'We don't learn democracy, we live it!' : consulting the pupil voice in Scottish schools

As the education for citizenship agenda continues to impact on schools, there is a need to begin the discussion around examining the kind of initiatives that can push it forward. In Scotland the proposals should, it is argued, permeate the curriculum throughout the school. Yet there is the fear that the responsibility of all can become the responsibility of none. This paper examines, through case study research carried out by the authors, initiatives in schools designed to take forward the citizenship agenda in the light of children's rights. The first two relate to firstly the impact of pupil councils in primary schools and secondly the impact of discussing controversial issues in the primary classroom. The third outlines the impact on values and dispositions of developing more participatory, democratic practice in the classroom. The paper concludes by calling for both more initiatives of this type and more evaluation of their worth

Slope diffraction analysis of TEM parallel- plate guide patterns

Slope diffraction analysis of TEM parallel plate guide pattern

Prediction of the pattern performance for the Aeroassist Flight Experiment (AFE) spacecraft

In order to provide a set of benchmark flight data for a reusable Aeroassisted Orbit Transfer Vehicle (AOTV) application, NASA undertook the development of an Aeroassisted Flight Experiment (AFE) which will be launched from the Space Shuttle. A representative aeroassist trajectory will be flown and sensor measurements of aerodynamic performance, thermal protection response, and plasma ionization reentry effects will be obtained. Discussed here is the spacecraft antenna. Estimates of signal transmissions from the AFE to the Tracking and Data Relay Satellites (TDRS) during the reentry period are given. The computer modeling of the antennas is presented with and without the reentry plasma