3,318 research outputs found
Repository Replication Using NNTP and SMTP
We present the results of a feasibility study using shared, existing,
network-accessible infrastructure for repository replication. We investigate
how dissemination of repository contents can be ``piggybacked'' on top of
existing email and Usenet traffic. Long-term persistence of the replicated
repository may be achieved thanks to current policies and procedures which
ensure that mail messages and news posts are retrievable for evidentiary and
other legal purposes for many years after the creation date. While the
preservation issues of migration and emulation are not addressed with this
approach, it does provide a simple method of refreshing content with unknown
partners.Comment: This revised version has 24 figures and a more detailed discussion of
the experiments conducted by u
A new Façade Concept for an Existing Office Building
In this paper a case study is presented relating to the redesign of an office buildingdating from the 1960s. Especially the detailing and the structural complexity ofdesigning the new double skin façade are described. The building consists of a twostoreypodium topped by a nine-storey tower, the overall height is 40m aboveground level. In order to optimise the building's energy efficiency and present thepublic a modern appearance the whole building is completely renovated. Theexisting building envelope which mainly consisted of prefabricated concreteelements was dismantled and is now replaced by a transparent floor to floor doubleskin façade. Within the renovation two new storeys (12th and 13th floor) are added
Minimizing Higgs Potentials via Numerical Polynomial Homotopy Continuation
The study of models with extended Higgs sectors requires to minimize the
corresponding Higgs potentials, which is in general very difficult. Here, we
apply a recently developed method, called numerical polynomial homotopy
continuation (NPHC), which guarantees to find all the stationary points of the
Higgs potentials with polynomial-like nonlinearity. The detection of all
stationary points reveals the structure of the potential with maxima,
metastable minima, saddle points besides the global minimum. We apply the NPHC
method to the most general Higgs potential having two complex Higgs-boson
doublets and up to five real Higgs-boson singlets. Moreover the method is
applicable to even more involved potentials. Hence the NPHC method allows to go
far beyond the limits of the Gr\"obner basis approach.Comment: 9 pages, 4 figure
Abelian symmetries in multi-Higgs-doublet models
N-Higgs doublet models (NHDM) are a popular framework to construct
electroweak symmetry breaking mechanisms beyond the Standard model. Usually,
one builds an NHDM scalar sector which is invariant under a certain symmetry
group. Although several such groups have been used, no general analysis of
symmetries possible in the NHDM scalar sector exists. Here, we make the first
step towards this goal by classifying the elementary building blocks, namely
the abelian symmetry groups, with a special emphasis on finite groups. We
describe a strategy that identifies all abelian groups which are realizable as
symmetry groups of the NHDM Higgs potential. We consider both the groups of
Higgs-family transformations only and the groups which also contain generalized
CP transformations. We illustrate this strategy with the examples of 3HDM and
4HDM and prove several statements for arbitrary N.Comment: 33 pages, 2 figures; v2: conjecture 3 is proved and becomes theorem
3, more explanations of the main strategy are added, matches the published
versio
Prochlo: Strong Privacy for Analytics in the Crowd
The large-scale monitoring of computer users' software activities has become
commonplace, e.g., for application telemetry, error reporting, or demographic
profiling. This paper describes a principled systems architecture---Encode,
Shuffle, Analyze (ESA)---for performing such monitoring with high utility while
also protecting user privacy. The ESA design, and its Prochlo implementation,
are informed by our practical experiences with an existing, large deployment of
privacy-preserving software monitoring.
(cont.; see the paper
Interstitial cortisol levels obtained by adipose tissue microdialysis in mechanically ventilated septic patients: correlations with total and free serum cortisol
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