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In the future, an increasing number of devices will be utilized in concert to support human activities, but little is known about how these interacting multidevice settings should be designed optimally in a human-centered manner. We report on a study in which we took two visions created by the Microsoft Corporation as a starting point. The aim of the paper is to describe a method for user-centered design that extends the ideas of a choreographic approach to interaction design and to demonstrate how micromovement analysis can be conducted in practice. We utilized a structural reorganization of movement continua originally presented in the videos for a first-person enactment of that choreography as a means to understand the kinesthetic quality and the potential of the implied choreographies. The approach underscores the influence of interaction designs on the moving and experiencing body, as well as the potential that the moving and experiencing body has for interaction design.

A discontinuous Galerkin (DG) surface integral equation method is proposed for electromagnetic scattering from targets with the impedance boundary condition (IBC). We present electric field integral equation (EFIE), magnetic field integral equation (MFIE), and self-dual integral equation formulations for the problem and study their numerical performance. On the basis of the results of these experiments, DG is developed for EFIE and MFIE (DG-EFIE and DG-MFIE). The convergence of the iterative solutions and the solution accuracy of DG-EFIE and DG-MFIE are further investigated for a wide range of surface impedances. The numerical performance of these formulations is found to be nearly complementary with respect to the surface impedance. The capability of the proposed DG solution strategy for calculating scattering from large multiscale IBC targets is demonstrated.

A new efficient approach for converting multipole series coefficients to plane wave samples and back is presented in detail. The presented algorithm utilizes the fast Fourier transform in order to speed up the process. It can be used to develop an efficient implementation of a broadband multilevel fast multipole algorithm (MLFMA). The numerical tests demonstrate that the presented process also allows full numerical error control, which is an important factor in a practical implementation.

The surface integral equation (SIE) method, discretized with the method of moments, is a well-established methodology for the scattering analysis of subwavelength plasmonic nanoparticles. SIEs are usually discretized with low-order basis functions that preserve the normal continuity of the surface currents across the edges arising in the meshed boundary, such as Rao-Wilton-Glisson (RWG) functions. However, the plasmonic enhancement modeling on sharp-edged particles is an extremely challenging task, especially due to the singular fields exerted at sharp corners, exposing a slow (or no) convergence in the computation of the scattering and absorption spectra. In this paper, we propose an alternative discretization strategy based on a discontinuous basis function set in conjunction with a volumetric-tetrahedral testing scheme. We demonstrate the potential of the proposed discretization scheme by studying scattering and absorption spectra of three canonical plasmonic polyhedra, i.e., a hexahedral, an octahedral, and a tetrahedral silver inclusion. The results expose an improved accuracy and faster convergence in both far-field and near-field regions when compared to the standard RWG implementation. The proposed discretization scheme can offer faster and more accurate routes towards the exploration and design of the plasmonic resonant spectrum of sharp-edged nanoparticles and nanoantennas.

Numerical solutions of various surface integral equation formulations in modeling resonating (lossless) closed impedance bodies are investigated. It is demonstrated that for certain values of purely imaginary surface impedances very strongly resonating field solutions can appear. Some of the considered formulations that are known to work well outside these resonances, e.g., for lossy surfaces, can lead to very poor accuracy or even diverging solutions at these resonances. Among the considered formulations only the combined source integral equations, discretized with a mixed scheme, both avoid the nonphysical spurious internal resonances and work reasonably well at the physical (impedance) resonances.

A new surface integral equation based formulation for computing characteristic modes of lossless and lossy dielectric and magneto-dielectric bodies is presented. For lossy objects, the imaginary part of an eigenvalue gives the ratio of the dissipated and radiated power, while the real part is connected to the ratio of the reactive and radiated power.

This paper studies constructing advanced effective materials using arrays of circular radially-anisotropic (RA) cylinders. Homogenization of such cylinders is considered in an electrodynamic case based on Mie scattering theory. The homogenization procedure consists of two steps. First, we present an effectively isotropic model for individual cylinders, and second, we discuss the modeling of a lattice of RA cylinders. Radial anisotropy brings us extra parameters, which makes it possible to adjust the desired effective response for a fixed frequency. The analysis still remains simple enough, enabling a derivation of analytical design equations. The considered applications include generating artificial magnetism using all-dielectric cylinders, which is currently a very sought-after phenomenon in optical frequencies. We also study how negative refraction is achieved using magnetodielectric RA cylinders.

In this study Video Card Game, a method originating in user-centred design, is studied as a learning design for teacher education. An experiment with second-year students of educational psychology is analysed on the basis of a trialogic view of collaborative knowledge construction, which integrates the perspectives of individuals, tools, and social situation in the study of learning (Hakkarainen, 2009). The analysis suggests that Video Card Game serves to promote learning, bridging the gap between theory and practice in teacher education.