1,344 research outputs found
Towards Governance or the Management of Cultural Landscapes
Many (World Heritage) cultural landscapes are a living environment for thousands of inhabitants, visitors, entrepreneurs, farmers and other land users. In order to manage such landscapes we have to consider the legal framework and the reality of the regional planning culture. The âlandscape of regional playersâ consists of a wide range of stakeholders. How should regions tackle natural and cultural heritage as an integrated part of regional development? The discussion of Austriaâs Hallstatt-Dachstein / Salzkammergut World Heritage region involves vertical and horizontal dimensions of governance, including politics, administration, private businesses and civil society
Renormalization of a Lorentz invariant doubled worldsheet theory
Manifestly T-duality covariant worldsheet string models can be constructed by
doubling the coordinate fields. We describe the underlying gauge symmetry of a
recently proposed Lorentz invariant doubled worldsheet theory that makes half
of the worldsheet degrees of freedom redundant. By shifting the Lagrange
multiplier, that enforces the gauge fixing condition, the worldsheet action can
be cast into various guises. We investigate the renormalization of this theory
using a non-linear background / quantum split by employing a normal coordinate
expansion adapted to the gauge-fixed theory. The propagator of the doubled
coordinates contains a projection operator encoding that half of them do not
propagate. We determine the doubled target space equations of motion by
requiring one-loop Weyl invariance. Some of them are generalizations of the
conventional sigma model beta-functions, while others seem to be novel to the
doubled theory: In particular, a dilaton equation seems related to the strong
constraint of double field theory. However, the other target space field
equations are not identical to those of double field theory.Comment: 32 pages; v2: motivation and discussion expanded, references adde
Higher-order hadronic and heavy-lepton contributions to the anomalous magnetic moment
We report about recent results obtained for the muon anomalous magnetic
moment. Three-loop kernel functions have been computed to obtain the
next-to-next-to-leading-order hadronic vacuum polarization contributions. The
numerical result, , is of
the same order of magnitude as the current uncertainty from the hadronic
contributions. For heavy-lepton corrections, analytical results are obtained at
four-loop order and compared with the known results.Comment: Contribution to the proceedings of Loops and Legs in Quantum Field
Theory, 27 April - 2 May 2014, Weimar, German
Hadronic contribution to the muon anomalous magnetic moment to next-to-next-to-leading order
We compute the next-to-next-to-leading order hadronic contribution to the
muon anomalous magnetic moment originating from the photon vacuum polarization.
The corresponding three-loop kernel functions are calculated using asymptotic
expansion techniques which lead to analytic expressions. Our final result,
, has the same order of
magnitude as the current uncertainty of the leading order hadronic contribution
and should thus be included in future analyses.Comment: 9 pages,v2: note on NLO hadronic light-by-light contribution added,
matches published version, Physics Letters B 734 (2014) 144-14
Transversal loss factor of an rf-focussing iris structure with rectangular holes
By replacing the irises in an electron linac by a slit one gets a structure capable of focussing/defocussing an electron beam (rf-quadrupoles). Therefore one can think of a combination of rf- and conventional magnetic quadrupoles for transversal focussing in linear-colliders. Furthermore they can meet the demands of BNS-damping without initial energy spread. Considering multibunch-operation of a collider, the long-range wake behaviour of this kind of structure has to be investigated. A three-cell structure has been built and investigated for dipole-type transversal long-range wakes. The experimental results are compared to numerical simulations done with MAFIA
Real Time Airborne Monitoring for Disaster and Traffic Applications
Remote sensing applications like disaster or mass event monitoring need the acquired data and extracted information within a very short time span. Airborne sensors can acquire the data quickly and on-board processing combined with data downlink is the fastest possibility to achieve this requirement. For this purpose, a new low-cost airborne frame camera system has been developed at the German Aerospace Center (DLR) named 3K-camera. The pixel size and swath width range between 15 cm to 50 cm and 2.5 km to 8 km respectively. Within two minutes an area of approximately 10 km x 8 km can be monitored. Image data are processed onboard on five computers using data from a real time GPS/IMU system including direct georeferencing. Due to high frequency image acquisition (3 images/second) the monitoring of moving objects like vehicles and people is performed allowing wide area detailed traffic monitoring
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