7,666 research outputs found
The Continuing Need to Distinguish Between Myth and Reality: Remarks of Edward B. Miller before the Commission on the Future of Worker-Management Relations
Testimony_Miller_090894.pdf: 117 downloads, before Oct. 1, 2020
Overview of Ka-band communications technology requirements for the space exploration initiative
In the Space Exploration Initiative, Ka-band frequencies are likely to carry the bulk of the communications traffic both in the vicinity of and on the return links from the moon and Mars. The four exploration architectures identified by the Synthesis Group are examined and Ka-band technology requirements to meet the data traffic needs and schedule are identified. Specific Ka-band technology requirements identified are: transmitters - 0.5 to 200 W with high efficiency; antennas - 5m and 9m diameter, with multiple beams and/or scanning beams; and spacecraft receivers - noise figure of 2 dB. For each component, the current state of technology is assessed and needed technology development programs are identified. It is concluded that to meet the schedules of lunar and Mars precursor missions beginning in approximately the year 2000, aggressive technology development and advanced development programs are required immediately for Ka-band communications systems components. Additionally, the greater data transmission rates for the cargo and piloted phases of the exploration program require further Ka-band communications technology developments targeted for operations beginning in about 2010
Witt differentials in the h-topology
Recent important and powerful frameworks for the study of differential forms
by Huber-Joerder and Huber-Kebekus-Kelly based on Voevodsky's h-topology have
greatly simplified and unified many approaches. This article builds towards the
goal of putting Illusie's de Rham-Witt complex in the same framework by
exploring the h-sheafification of the rational de Rham-Witt differentials.
Assuming resolution of singularities in positive characteristic one recovers a
complete cohomological h-descent for all terms of the complex. We also provide
unconditional h-descent for the global sections and draw the expected
conclusions. The approach is to realize that a certain right Kan extension
introduced by Huber-Kebekus-Kelly takes the sheaf of rational de Rham-Witt
forms to a qfh-sheaf. As such, we state and prove many results about
qfh-sheaves which are of independent interest
On Lower Bounds for -multiplicities
A recent continuous family of multiplicity functions on local rings was
introduced by Taylor interpolating between Hilbert-Samuel and Hilbert-Kunz
multiplicities. The obvious goal is to use this as a tool for deforming results
from one to the other. The values in this family which do not match these
classic variants however are not known yet to be well-behaved. This article
explores lower bounds for these intermediate multiplicities as well as gives
evidence for analogies of the Watanabe-Yoshida minimality conjectures for
unmixed singular rings.Comment: 10 page
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