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The purpose of this paper is to clarify the status of Maxwell's tensor with respect to the virtual power principle (VPP).

Mathematical analysis is employed.

The VPP, logically stronger, is more fundamental. Maxwell's tensor derives from it, under further restrictive assumptions, and hence, its range of applicability is limited. In particular, it fails to deal with some aspects of magnetostriction.

The paper shows that when magnetic constitutive laws depend, locally, on strain, the body force is not, as a rule, the divergence of the Maxwell tensor. People who intend to compute forces this way should be wary of that.

The greatest mistakes and delusions of human history have come about through logically drawing conclusions from an omissive set of premisses. Cybernetics, being the science of the study and redirection of feedback, is the science of consequences; its essential task is to recognize and deal with all feedback effects, including the consequences of such omissive conceptions – the so‐called blind spot. Gives some examples of the blind spot as it has manifested itself throughout history in the world of science. Concludes that cybernetics can defuse this blind spot which has perennially plagued human development, individually and societally.

The greatest mistakes and delusions of human history have come about through logically drawing conclusion from an omissive set of premises. Cybernetics, being the science of the study and redirection of feedback, is the science of consequences; its essential task is to recognize and deal with all feedback effects, including the consequences of such omissive conceptions – the so‐called blind spot. Gives some examples of the blind spot as it has manifested itself throughout history in the world of science. Concludes that cybernetics can defuse this blind spot which has perennially plagued human development, individually and societally.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The divergence equations in Maxwell’s theory are Gauss law and the statement that magnetic monopoles do not exist; from this point of view these two equations are fundamental. However, from a practical point of view, it is generally believed that Maxwell’s divergence equations are redundant and may be ignored provided that they are satisfied at some time t‐0. It has been proved recently that this idea is not correct for boundary‐initial value problems. To make mathematical arguments more accessible, we analyse here the role of the divergence equations in the framework of 2D‐electromagnetism.

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry that the incomplete determinism in Nature opens to the occurrence of innovation, growth, organization, teleology communication, control, contest and freedom. The new tier to the methodological edifice that cybernetics provides stands on the earlier tiers, which go back to the Ionians (c. 500 BC). However, the new insights reveal flaws in the earlier tiers, and their removal strengthens the entire edifice. The new concepts of teleological activity and contest allow the clear demarcation of the military sciences as those whose subject matter is teleological activity involving contest. The paramount question “what ought to be done”, outside the empirical realm, is embraced by the scientific methodology. It also embraces the cognitive sciences that ask how the human mind is able to discover, and how the sequence of discoveries might converge to a true description of reality.

A new finite volume scheme to solve Maxwell’s equations is presented. The approach is based on a leapfrog time scheme and a centered flux formula. This method is well suited for handling complex geometries, and therefore we can use unstructured grids. It is also able to capture the discontinuities of the electromagnetic fields through different media, without producing spurious oscillations. Owing to these properties, we can treat difficult problems, such a computing a scattered wave across complex objects. An analysis of the scheme is presented and numerical experiments are performed.

The purpose of this paper is to study the transient thermoelastic interactions in a nonlocal rotating magneto-thermoelastic medium with temperature-dependent properties. Three-phase-lag (TPL) model of generalized thermoelasticity is employed to study the problem. An initial magnetic field with constant intensity acts parallel to the bounding plane. Therefore, Maxwell's theory of electrodynamics has been effectively introduced and the expression for Lorentz's force is obtained with the help of modified Ohm's law.

The normal mode technique has been adopted to solve the resulting non-dimensional coupled field equations to obtain the expressions of physical field variables.

For uniformly distributed thermal load, normal displacement, temperature distribution and stress components are calculated numerically with the help of MATLAB software for a copper material and the results are illustrated graphically. Some particular cases of interest are also deduced from the present study.

Influences of nonlocal parameter, rotation, temperature-dependent properties, magnetic field and time are carefully analyzed for mechanically stress free boundary and uniformly distributed thermal load. The present work is useful and valuable for analysis of problem involving thermal shock, nonlocal parameter, temperature-dependent elastic and thermal moduli.

There are two conflicting views about electromagnetic phenomena. The first is based on the action between stationary and moving particles of electric charge and the second on energy distributions in electric and magnetic fields. The difference between these approaches is seen most clearly in the roles assigned to the potentials. According to the particle view the potentials convey the force from one particle to another, whereas in the field approach the potentials are system parameters related to the field energy. The article compares the two views and concludes that the particle view faces impossible difficulties because it ascribes local significance to quantities which are unobservable and conflicts with the quantum‐mechanical understanding of charge as a statistical distribution.

The design of microwave circuits requires detailed knowledge on the electromagnetic properties of the transmission lines used. This can be obtained by applying Maxwell’s equations to a longitudinally homogeneous waveguide structure, which results in an eigenvalue problem for the propagation constant. Special attention is paid to the so‐called perfectly matched layer boundary conditions (PML). Using the finite integration technique we get an algebraic formulation. The finite volume of the PML introduces additional modes that are not an intrinsic property of the waveguide. In the presence of losses or absorbing boundary conditions the matrix of the eigenvalue problem is complex. A method which avoids the computation of all eigenvalues is presented in an effort to find the few propagating modes one is interested in. This method is an extension of a solver presented by the authors in a previous paper which analyses the lossless case. Using mapping relations between the planes of eigenvalues and propagation constants a strip in the complex plane is determined containing the desired propagation constants and some that correspond to the PML modes. In an additional step the PML modes are eliminated.The numerical effort of the presented method is reduced considerably compared to a full calculation of all eigenvalues.