9,812 research outputs found
Three dimensional laminar boundary layer with small cross-flow
Important problems involving three-dimensional boundary
layer occur in almost all internal and external aerodynamic
configurations. For many of these, the flow outside the boundary
layer may be resolved into a large principal component and a
small crosswise velocity. In this paper, three-dimensional
laminar boundary-layer flows over flat and curved surfaces are
treated under such a simplification. For flat surfaces, the solutions
demonstrate the effect of the free stream turning on the
velocity profiles in the crosswise and primary flow directions.
When the surface curvature is large and varies so as to resemble a
corner, the computed examples show the manner in which the
asymmetric behavior of the boundary layer results from the
cross-flow. The detailed examples are chosen to illustrate flows occurring on the casing and in the blade fillets of turbomachinery
National strategy for neighbourhood renewal : a framework for consultation
"This report contains FEDA’s response to
National strategy for neighbourhood renewal:
a framework for consultation, the report by
the Social Exclusion Unit. FEDA supports
the vision set out in the paper and would
like to play a significant role in taking the
strategy forward. Detailed responses are
given to the chapters relating to reviving
local economies, reviving communities
and leadership and joint working" -- back cover
Stress testing of real credit portfolios
Stress testing has become a crucial point on the Basel II agenda, mainly as Pillar I estimates do not explicitly take portfolio concentration into account. We start from the credit portfolio of the German pension insurer being a cross-sectional representation of the German economy and subsequently compose three bank portfolios corresponding to a small, medium and large bank. We apply univariate and multivariate stress tests both by using the Internal Rating based (IRB) model and by a model that additionally allows for variation of correlation. In a severe multivariate stress scenario based on historical data for Germany IRB capital requirements increase by more than 80% with little differences between the credit portfolios. If stress testing is additionally applied to correlation, the Value-at-Risk increases by up to 300% and portfolio differences materialize. --Credit Portfolio,Exposure concentration,Stress Testing,Basel II,Economic Capital
Measurement of single event upsets in the ALICE-TPC front-end electronics
The Time Projection Chamber of the ALICE experiment at the CERN Large Hadron
Collider features highly integrated on-detector read-out electronics. It is
following the general trend of high energy physics experiments by placing the
front-end electronics as close to the detector as possible -- only some 10 cm
away from its active volume. Being located close to the beams and the
interaction region, the electronics is subject to a moderate radiation load,
which allowed us to use commercial off-the-shelf components. However, they
needed to be selected and qualified carefully for radiation hardness and means
had to be taken to protect their functionality against soft errors, i.e. single
event upsets.
Here we report on the first measurements of LHC induced radiation effects on
ALICE front-end electronics and on how they attest to expectations
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