834 research outputs found
Quality assurance procedures for V378A matrix resin
A characterization methodology has been developed on which to base quality assurance procedures for U.S. Polymeric V378A bismaleimide matrix resin. Chemical composition is established by partition reverse phase and size exclusion liquid chromatography. Cure rheology behavior is quantitatively characterized by dynamic viscoelastic analysis using the parallel plate technique. The overall cure process is characterized by differential scanning calorimetry. The sensitivity of the procedures is evaluated by studying the effects of ambient out time on the chemical end behaviorial properties of the resin
Reply to "Comment on `Resilience of gated avalanche photodiodes against bright illumination attacks in quantum cryptography'"
This is a Reply to the Comment by Lydersen et al. [arXiv: 1106.3756v1]
Development and demonstration of manufacturing processes for fabricating graphite/LARC 160 polyimide structural elements
The development and demonstration of manufacturing technologies for the structural application of Celion graphite/LARC-160 polyimide composite material is discussed. Process development and fabrication of demonstration components are discussed. Process development included establishing quality assurance of the basic composite material and processing, nondestructive inspection of fabricated components, developing processes for specific structural forms, and qualification of processes through mechanical testing. Demonstration components were fabricated. The demonstration components consisted of flat laminates, skin/stringer panels, honeycomb panels, chopped fiber compression moldings, and a technology demonstrator segment (TDS) representative of the space shuttle aft body flap
The emergence of 4-cycles in polynomial maps over the extended integers
Let ; for each integer it is interesting to
consider the number of iterates , if possible, needed to satisfy
. The sets generated by the iterates of are
called cycles. For it is known that cycles of length 1 and 2
occur, and no others. While much is known for extensions to number fields, we
concentrate on extending by adjoining reciprocals of primes. Let
denote extended by adding in
the reciprocals of the primes and all their products and
powers with each other and the elements of .
Interestingly, cycles of length 4, called 4-cycles, emerge for polynomials in
under the appropriate
conditions. The problem of finding criteria under which 4-cycles emerge is
equivalent to determining how often a sum of four terms is zero, where the
terms are times a product of elements from the list of primes. We
investigate conditions on sets of primes under which 4-cycles emerge. We
characterize when 4-cycles emerge if the set has one or two primes, and
(assuming a generalization of the ABC conjecture) find conditions on sets of
primes guaranteed not to cause 4-cycles to emerge.Comment: 14 pages, 1 figur
Practical security bounds against the Trojan-horse attack in quantum key distribution
In the quantum version of a Trojan-horse attack, photons are injected into
the optical modules of a quantum key distribution system in an attempt to read
information direct from the encoding devices. To stop the Trojan photons, the
use of passive optical components has been suggested. However, to date, there
is no quantitative bound that specifies such components in relation to the
security of the system. Here, we turn the Trojan-horse attack into an
information leakage problem. This allows us quantify the system security and
relate it to the specification of the optical elements. The analysis is
supported by the experimental characterization, within the operation regime, of
reflectivity and transmission of the optical components most relevant to
security.Comment: 18 pages, 11 figures. Some typos correcte
- …