Dipole radiation in uniaxial bianisotropic medium

Radiation from an electric dipole oriented parallel to the distinguished axis of a uniaxial bianisotropic medium is considered. The electromagnetic fields are represented in full generality in terms of two scalar Hertz potentials. An analytic solution for these scalar potentials is obtained.<>     

New expressions for depolarization dyadics in uniaxial dielectric-magnetic media

We present some novel expressions for the depolarization dyadics in uniaxial dielectric-magnetic media. These expressions were obtained by generalizing the Fikioris approach for extracting the singular behaviour of integrals involving the dyadic Green functions and the source current density distributions. Cubical, cylindrical and spherical geometries serve as examples for a discussion of the depolarization dyadics' dependence on geometry and anisotropy.     

Brief Overview of Recent Developments on Negative Phase–Velocity Mediums (alias Left–Handed Materials)

This brief overview covers a rapidly occurring development in the area of microwave composite materials: isotropic dielectric–magnetic mediums wherein the phase velocity vector and the time–averaged Poynting vector are oppositely directed. Such materials have also been inappropriately designated as left–handed materials. Ramifications for aberration–free lenses, homogenization approaches, and complex mediums are also presented.     

Using coverage to automate and improve test purpose based testing

Test purposes have been presented as a solution to avoid the state space explosion when selecting test cases from formal models. Although such techniques work very well with regard to the speed of the test derivation, they leave the tester with one important task that influences the quality of the overall testing process: test purposes have to be formulated manually. In this paper, we present an approach that assists a test engineer with test purpose design in two ways: it allows automatic generation of coverage based test suites and can be used to automatically exercise those aspects of the system that are missed by hand-crafted test purposes. We consider coverage of Lotos specifications, and show how labeled transition systems derived from such specifications have to be extended in order to allow the application of logical coverage criteria to Lotos specifications. We then show how existing tools can be used to efficiently derive test cases and suggest how to use the coverage information to minimize test suites while generating them.     

Needles and pillboxes in anisotropic mediums

We establish a connection between the singularities of dyadic Green functions in biaxial-dielectric media arising from eigenfunction expansions in cylindrical coordinates and general expressions of depolarization dyadics. The results are then extended to general anisotropic-dielectric media     

Comment on "Scattering by a bi-isotropic body" [and reply]

The author comments on a paper by Monzon (IEEE Trans. Antennas Propagat., vol.43, p.1288-96, Nov. 1995). The author comments that Monzon gave no indication as to whether the nonreciprocal variety of bi-anisotropic media can or do exist. The present comment notes that there is no reason to suggest that these can or do exist. A reply is presented by Monzon where he feels that the situation regarding these materials is not yet settled.     

Special Issue of Bianisotropics 2000: Guest Editorial

An introduction to this special issue devoted to Bianisotropics 2000 – 8th International Conference on Electromagnetics of Complex Media, is provided.     

Constraint on linear,spatiotemporally nonlocal,spatiotemporally nonhomogeneous constitutive relations

The structure of modern electromagnetic theory imposes a fundamental constraint on the constitutive relations which describe linear material media. Here, in extension to previous work, we provide a proof of this algebraic constraint for the most general type of linear medium: one that is bianisotropic and spatiotemporally nonhomogeneous as well as spatiotemporally nonlocal.     

New Expressions for Depolarization Dyadics in an Axially Uniaxial Bianisotropic Medium

Novel expressions for the depolarization dyadics in an axially uniaxial bianisotropic medium (AUBM) are presented. Explicit formulae for the depolarization dyadics are derived for cubical, cylindrical and spherical geometries and their dependence on the magnetoelectric coupling parameter is studied graphically.     

Fault-Based Conformance Testing in Practice

Conforming to protocol speci.cations is a critical issue in modern distributed software systems. Nowadays, complex service infrastructures, such as Voice-over-IP systems, are usually built by combining components of di.erent vendors. If the components do not correctly implement the various protocol speci.cations, failures will certainly occur. In the case of emergency calls this may be even life-threatening. Functional black-box conformance testing, where one checks the conformance of the implemented protocol to a speci.cation becomes therefore a major issue. In this work, we report on our experiences and .ndings when applying fault-based conformance testing to an industrial application. Besides a discussion on modeling and simpli.cations we present a technique that prevents an application from implementing particular faults. Faults are modeled at the level of the speci.cation. We show how such a technique can be adapted to speci.cations with large state spaces and present results obtained when applying our technique to the Session Initiation Protocol and to the Conference Protocol. Finally, we compare our results to random and scenario based testing.