Alfvén Waves in the Lower Solar Atmosphere

The flow of energy through the solar atmosphere and the heating of the Sun's outer regions are still not understood. Here, we report the detection of oscillatory phenomena associated with a large bright-point group that is 430,000 square kilometers in area and located near the solar disk center. Wavelet analysis reveals full-width half-maximum oscillations with periodicities ranging from 126 to 700 seconds originating above the bright point and significance levels exceeding 99%. These oscillations, 2.6 kilometers per second in amplitude, are coupled with chromospheric line-of-sight Doppler velocities with an average blue shift of 23 kilometers per second. A lack of cospatial intensity oscillations and transversal displacements rules out the presence of magneto-acoustic wave modes. The oscillations are a signature of Alfvén waves produced by a torsional twist of ±22 degrees. A phase shift of 180 degrees across the diameter of the bright point suggests that these torsional Alfvén oscillations are induced globally throughout the entire brightening. The energy flux associated with this wave mode is sufficient to heat the solar corona.

Equalisation of time variant multipath channels using amplitude banded LMS algorithms

For the purpose of equalisation of rapidly time variant multipath channels, we derive a novel adaptive algorithm, the amplitude banded LMS (ABLMS); which implements a nonlinear adaptation based on a coefficient matrix. Then we develop the: ABLMS algorithm as the adaptation procedure for a linear transversal equaliser (LTE) and a decision feedback equaliser (DFE) where a parallel adaptation scheme is deployed. Computer simulations demonstrate that with a small increase of computational complexity, the ABLMS based parallel equalisers provide a significant improvement related to the conventional LMS DFE and the LMS LTE in the case of a second order Markov communication channel model.

Gender and Cosmopolitanism in Europe: A Feminist Perspective

Gender and Cosmopolitanism in Europe combines a feminist critique of contemporary and prominent approaches to cosmopolitanism with an in-depth analysis of historical cosmopolitanism and the manner in which gendered symbolic boundaries of national political communities in two European countries are drawn. Exploring the work of prominent scholars of new cosmopolitanism in Britain and Germany, including Held, Habermas, Beck and Bhabha, it delivers a timely intervention into current debates on globalisation, Europeanisation and social processes of transformation in and beyond specific national societies.

A rigorous examination of the emancipatory potential of current debates surrounding cosmopolitanism in Europe, this book will be of interest to sociologist and political scientists working on questions of identity, inclusion, citizenship, globalisation, cosmopolitanism and gender.
Contents: Introduction: gendered cosmopolitanism: the scope of this book; Who belongs? Who is the Other?; Recognition, social equality and the current EU anti-discrimination policy; Kulturnation and the homogenised notion of community belonging: Jürgen Habermas's and Ulrich Beck's approaches to 'European' cosmopolitanism; Global trade, the city and commercial cosmopolitanism: David Held's and Homi K. Bhabha's approaches to new cosmopolitanism; About dead-ends, one-way streets and critical crossroads; Transversal conversations on the scope of new cosmopolitanism beyond the Eurocentric framework; Bibliography; Index.