1,636 research outputs found
A new precision measurement of the {\alpha}-decay half-life of 190Pt
A laboratory measurement of the -decay half-life of Pt has
been performed using a low background Frisch grid ionisation chamber. A total
amount of 216.60(17) mg of natural platinum has been measured for 75.9 days.
The resulting half-life is years, with a total
uncertainty of 3.2%. This number is in good agreement with the half-life
obtained using the geological comparison method
Controlled low-temperature molecular manipulation of sexiphenyl molecules on Ag(111) using scanning tunneling microscopy
A novel scanning tunneling microscope manipulation scheme for a controlled
molecular transport of weakly adsorbed molecules is demonstrated. Single
sexiphenyl molecules adsorbed on a Ag(111) surface at 6 K are shot towards
single silver-atoms by excitation with the tip. To achieve atomically straight
shooting paths, an electron resonator consisting of linear standing wave fronts
is constructed. The sexiphenyl manipulation signals reveal a pi-ring flipping
as the molecule moves from hcp to fcc site. Abinitio calculations show an
incorporation of the Ag atom below the center of a pi-ring.Comment: 4 pages, 4 figures, accepted for publication in Phys. Rev. Let
Evaluation von Simulationsmodellen zur Prognose des Energiebedarfs von Regalbediengeräten mit empirisch erhobenen Messdaten
Der Einsatz energieeffizienter Systeme hat bei der Entwicklung, Planung und Realisierung von Projekten einen immer steigenden Einfluss. Zur Prognose des Energiebedarfs automatisierter, intralogistischer Systeme stehen derzeit verschiedene Ansätze zur Verfügung. In diesem Artikel wird deshalb die Evaluation von Berechnungsmethoden mit empirischen Messdaten am Beispiel des Regalbediengeräts beschrieben und analysiert. Abschließend werden anhand der Analyseergebnisse des Evaluationsprozesses verschiedene Thesen aufgestellt und untersucht
Linking the Quark Meson Model with QCD at High Temperature
We model the transition of a system of quarks and gluons at high energies to
a system of quarks and mesons at low energies in a consistent renormalization
group approach. Flow equations interpolate between the physics of the
high-temperature degrees of freedom and the low-temperature dynamics at a scale
of 1 GeV. We also discuss the dependence of the equation of state on baryon
density and compare our results with recent lattice gauge simulations.Comment: 11 pages, 4 figures additional discussion of the second order phase
transitio
Proving sequential consistency by model checking
Sequential consistency is a multiprocessor memory model of both practical and theoretical importance. Unfortunately, the general problem of verifying that a finitestate protocol implements sequential consistency is undecidable, and in practice, validating that a real-world, finitestate protocol implements sequential consistency is very time-consuming and costly. In this work, we show that for memory protocols that occur in practice, a small amount of manual effort can reduce the problem of verifying sequential consistency into a verification task that can be discharged automatically via model checking. Furthermore, we present experimental results on a substantial, directorybased cache coherence protocol, which demonstrate the practicality of our approach.
Enhanced Symmetries of Orbifolds from Moduli Stabilization
We study a supersymmetric field theory in six dimensions compactified on the
orbifold T^2/Z_2 with two Wilson lines. After supersymmetry breaking, the
Casimir energy fixes the shape moduli at fixed points in field space where the
symmetry of the torus lattice is enhanced. Localized Fayet-Iliopoulos terms
stabilize the volume modulus at a size much smaller than the inverse
supersymmetry breaking scale. All moduli masses are smaller than the gravitino
mass.Comment: 24 pages, 10 figures, Appendix added, matches published versio
Verbesserung der Lebensdauer von medizinischen Modellen durch niederschwellig produzierte Instruktionsvideos
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