2 resultados para Sportsturf and greens

em University of Queensland eSpace - Australia


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This paper discusses the German Greens' recent policy on Israel and Palestine, from the beginning of the first red-green federal government to the present. It looks at Green Foreign Minister Joschka Fischer's diplomatic role in the Middle East, and the Greens' current very mild policy with regards to Israel, especially when compared to earlier Green attitudes to the region. This is explained with reference to both the continuing relevance of German history to German foreign policy, and the constraints that participation in the federal coalition - and supplying Germany's Foreign Minister - place on the Greens. The influence of history and power on the German Greens is further illustrated by a comparison of German Green attitudes to Israel with the US Greens' much more critical position.

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The precise evaluation of electromagnetic field (EMF) distributions inside biological samples is becoming an increasingly important design requirement for high field MRI systems. In evaluating the induced fields caused by magnetic field gradients and RF transmitter coils, a multilayered dielectric spherical head model is proposed to provide a better understanding of electromagnetic interactions when compared to a traditional homogeneous head phantom. This paper presents Debye potential (DP) and Dyadic Green's function (DGF)-based solutions of the EMFs inside a head-sized, stratified sphere with similar radial conductivity and permittivity profiles as a human head. The DP approach is formulated for the symmetric case in which the source is a circular loop carrying a harmonic-formed current over a wide frequency range. The DGF method is developed for generic cases in which the source may be any kind of RF coil whose current distribution can be evaluated using the method of moments. The calculated EMFs can then be used to deduce MRI imaging parameters. The proposed methods, while not representing the full complexity of a head model, offer advantages in rapid prototyping as the computation times are much lower than a full finite difference time domain calculation using a complex head model. Test examples demonstrate the capability of the proposed models/methods. It is anticipated that this model will be of particular value for high field MRI applications, especially the rapid evaluation of RF resonator (surface and volume coils) and high performance gradient set designs.