Volker Braun

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Societal development will lead to changes in the way mobile and wireless communication systems are used. Essential services such as e-banking, elearning, and e-health will continue to proliferate and become more mobile. On-demand information and entertainment (e.g., in the form of augmented reality) will progressively be delivered over mobile and wireless(More)
We investigate orientifolds of type II string theory on K3 and Calabi-Yau 3-folds with intersecting D-branes wrapping special Lagrangian cycles. We determine quite generically the chiral massless spectrum in terms of topological invariants and discuss both orbifold examples and algebraic realizations in detail. Intriguingly, the developed techniques provide(More)
Developmental processes are thought to be highly complex, but there have been few attempts to measure and compare such complexity across different groups of organisms. Here we introduce a measure of biological complexity based on the similarity between developmental and computer programs. We define the algorithmic complexity of a cell lineage as the length(More)
We systematically analyse globally consistent SU(5) GUT models on intersecting D7-branes in genuine Calabi-Yau orientifolds with O3and O7-planes. Beyond the well-known tadpole and K-theory cancellation conditions there exist a number of additional subtle but quite restrictive constraints. For the realisation of SU(5) GUTs with gauge symmetry breaking via(More)
OBJECTIVE Animal studies have demonstrated that reperfusion disorders occurring after cardiac arrest affect outcome. Reperfusion injury can be caused by activation of complement, polymorphonuclear leukocytes (PMN), and PMN-endothelial interaction. We studied different specific markers of these processes during and after cardiopulmonary resuscitation in(More)
In 2020, mobile and wireless traffic volume is expected to increase thousand-fold over 2010 figures. Moreover, an increase in the number of wirelessly-connected devices to counts in the tens of billions will have a profound impact on society. Massive machine communication, forming the basis for the Internet of Things, will make our everyday life more(More)
The Electronic Tool Integration platform (ETI) associated with STTT is designed for the interactive experimentation with and coordination of heterogeneous tools. ETI users are supported by an advanced, personalized Online Service guiding experimentation, coordination, and simple browsing of the available tool repository according to their degree of(More)