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A fully integrated model of coupling between the electromagnetic field and multiconductor cabling is developed using the transmission-line matrix (TLM) method. In this model, the multiconductor cables are represented by multiconductor transmission lines which connect to the general TLM mesh. A basic TLM model of straight multiconductor lines is developed first, followed by the derivation of a general multiconductor junction model suitable for describing more complex configurations. Sample numerical results are presented to confirm validity and efficiency of the model. Index Terms - Multiconductor transmission lines, time-domain analysis, transmission-line matrix methods.

Full-wave modeling of the coupling structure between a double-ridge waveguide and dielectric-loaded resonator in a rectangular cavity through an iris is presented. Eigen modes of the double-ridge waveguide, and the discontinuities of the structures are obtained by rigorous mode-matching method. By applying the cascading procedure, the reflection coefficients of the coupling structure can be obtained. From the phase variation of the reflection coefficient and circuit theory, resonant frequency and input/output coupling of the structure are accurately determined. An equivalent circuit model of the resonant structure is established. The computed results are compared with those obtained by other methods and shown to be in good agreement, which verify the theory. Index Terms - Couplings, dielectric resonators, filters, ridge waveguides.

The torque of magnetic coupling with different magnetic poles has been investigated by theoretical computations with both FEA and torque formula techniques. The torque of magnetic coupling is sensitive to the number of magnetic poles, and it decreases with increasing the distance between the magnetic rings. From our theoretical computations, we find that we can increase the torque by increasing the number of poles for magnetic coupling between magnetic rings with short distance; however, this is not true for magnetic rings with large separation. We also demonstrate that the theoretical computations of both MagNet software and torque formula established by Furlani are quite consistent and useful for computing the torque of various magnetic couplings. Finally, the theoretical calculation has been successfully tested by using an experimental data taken from a NdFeB magnetic coupling.

A finite element model of hot rolling is described. It is based upon the flow formulation, with a Norton-Hoff purely vispoplastic behavior. We use a steady state approach with free surface updating by minimizing the material flux through the surface. To compute stresses, smoothed derivatives of the velocity are obtained and the strain rate tensor and stress deviator computed from them. Then the pressure field is calculated by a least squares method on the residual of equilibrium equations. A simplified thermal transfer equation is obtained by neglecting internal conduction. Boundary conditions include a contact temperature accounting for a thermal contact resistance and heat generated by friction. Thermomechanical coupling is performed. It is applied to simulation of a multipass blooming sequence in order to evaluate metallurgical evolution of the product. The interest of stresses computation is demonstrated for predicting surface crack opening and closing in shape rolling, with comparison to experimental trends.

Large structures in nuclear power plants are often separated by very thin fluid-filled cavities. For example, core support structures, thermal shields, and reactor vessels are usually large concentric cylindrical shells with annuli between them as small as 2 percent of the shell diameter. Such thin cavities cause the structures to be very strongly coupled, and such coupling must be accurately modeled to predict the dynamic responses of new designs to turbulence, pump acoustic loading, loss-of-coolant accidents, and seismic events. This paper summarizes a very versatile and efficient method of solving these problems with small personal computers. Among other things, this method uses component modal synthesis with the hybrid approach, and the solution of the resulting unsymmetric eigenvalue problem for the coupled vibration modes. System responses are then found in terms of 'right' and 'left' eigenvectors. Comparisons with test results are also presented.