7,169 research outputs found
Discussion on complexity and TCAS indicators for coherent safety net transitions
Transition between Separation Management in ATM
and Collision Avoidance constitutes a source of potential risks due
to non-coherent detection and resolution clearances between them.
To explore an operational integration between these two safety
nets, a complexity metric tailored for both Separation
Management and Collision Avoidance, based on the intrinsic
complexity, is proposed.
To establish the framework to compare the complexity metric with
current Collision Avoidance detection metrics, a basic pair-wise
encounter model has been considered. Then, main indicators for
horizontal detection of TCAS, i.e. tau and taumod, have been
contrasted with the complexity metric.
A simple method for determining the range locus for specific
TCAS tau values, depending on relative speeds and encounter
angles, was defined. In addition, range values when detection
thresholds were infringed have been found to be similar, as well as
its sensitivity to relative angles.
Further work should be conducted for establishing a framework
for the evaluation and validation of this complexity metric. This
paper defines basic principles for an extended evaluation,
including multi-encounter scenarios and longer look ahead times
Some results on rational surfaces and Fano varieties
The goal of this article is to study the equations and syzygies of embeddings
of rational surfaces and certain Fano varieties. Given a rational surface X and
an ample and base-point-free line bundle L on X, we give an optimal numerical
criterion for L to satisfy property Np. This criterion turns out to be a
characterization of property Np if X is anticanonical. We also prove syzygy
results for adjunction bundles and a Reider type theorem for higher syzygies.
For certain Fano varieties we also prove results on very ampleness and higher
syzygies.Comment: 26 pages, AMSTe
- …