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We study how effective material parameters can be defined for Maxwell's equations when taking dispersion into account. The reasoning is based on the concept of dispersion relations, and is consequently primarily concerned with lossless media. We essentially require that the effective material parameters should produce the same dispersion relations as the heterogeneous problem, which implies

We propose a new method for the simulation of microcellular propagation channels, which includes both deterministic and stochastic aspects. First, the geometrical layouts of "typical" deployment areas, called "Virtual Cell Deployment Areas" (VCDA), as well as routes of the mobile station (MS) through the VCDA, are defined. Then, the delays and directions-of-arrival of multipath clusters can be tra

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This study explored (a) parents' process of changes and challenges in their patterns of daily activities after the onset of diabetes in their children; and (b) how personal gender relations can restrain or create functional strategies for managing the changes and challenges of illness. Interviews were conducted with 21 mothers and 15 fathers of 23 children with type 1 diabetes 8 to 10 months after

Biomass or bioenergy is attracting growing attention as a sustainable and renewable energy source, which is abundant and available around the world. There are many studies on bioenergy potentials with estimates ranging from less than 100 EJ/yr to more than 500 EJ/yr in 2050. Some studies indicate that by 2100 more than 1000 EJ/yr is conceivable. To comprehend the magnitude of the estimates, the wo

A directly cooled winding in an electrical machine is an appealing solution for a traction application when the electrical machine is operating near peak power for extended periods of time. This directly cooled winding is based on a laminated structure where the power losses in the conducting strips are instantly dissipated by an air-flow between the strips. As an outcome, the hottest component of

The direct and inverse scattering problems for a plane-stratified viscoelastic medium excited by a transient plane wave of SH or P-SV type are treated. The viscoelastic medium is characterized by two time and space dependent memory functions and a spatially dependent density. The direct and inverse problems are solved by a time-domain wave propagator method that is related to the Green functions t

F1 and F2 frequencies of the vowels /i/, /a/ and /u/ were measured in speech directed to an infant and to adults. The vowels were taken from content words as well as function words. The results showed that the vowel triangles in speech to the infant were expanded compared to those in speech to adults, but only in the content words. For function words, the opposite pattern was found: adults produce