Search results for "FOS"
showing 10 items of 15075 documents
Applications and non-idealities of submicron Al–AlOx–Nb tunnel junctions
2016
We have developed a technique to fabricate sub-micron, 0.6µm×0.6µm Al-AlOx-Nb tunnel junctions using a standard e-beam resist, angle evaporation and double oxidation of the tunneling barrier, resulting in high quality niobium, as determined by the the high measured values of the critical temperature TC ∼ 7.5 K and the gap ∆ ∼ 1.3 meV. The devices show great promise for local nanoscale thermometry in the temperature range 1 - 7.5 K. Electrical characterization of the junctions was performed at sub-Kelvin temperatures both with and without an external magnetic field, which was used to suppress superconductivity in Al and thus bring the junction into a normal-metal-insulator-superconductor (NI…
QCD NLO with Powheg matching and top threshold matching in WHIZARD
2016
We present the status of the automation of NLO processes within the event generator WHIZARD. The program provides an automated FKS subtraction and phase space integration over the FKS regions, while the (QCD) NLO matrix element is accessed via the Binoth Les Houches Interface from an externally linked one-loop program. Massless and massive test cases and validation are shown for several e+e- processes. Furthermore, we discuss work in progress and future plans. The second part covers the matching of the NRQCD prediction with NLL threshold resummation to the NLO continuum top pair production at lepton colliders. Both the S-wave and P-wave production of the top pair are taken into account in t…
Hölder regularity for stochastic processes with bounded and measurable increments
2022
We obtain an asymptotic Hölder estimate for expectations of a quite general class of discrete stochastic processes. Such expectations can also be described as solutions to a dynamic programming principle or as solutions to discretized PDEs. The result, which is also generalized to functions satisfying Pucci-type inequalities for discrete extremal operators, is a counterpart to the Krylov-Safonov regularity result in PDEs. However, the discrete step size $\varepsilon$ has some crucial effects compared to the PDE setting. The proof combines analytic and probabilistic arguments.
Measurement of the top quark charge in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
2013
A measurement of the top quark electric charge is carried out in the ATLAS experiment at the Large Hadron Collider using 2.05 fb[superscript −1] of data at a centre-of-mass energy of 7 TeV. In units of the elementary electric charge, the top quark charge is determined to be 0.64 ± 0.02 (stat.) ± 0.08 (syst.) from the charges of the top quark decay products in single lepton t[¯ over t] candidate events. This excludes models that propose a heavy quark of electric charge −4/3, instead of the Standard Model top quark, with a significance of more than 8σ.
Kolmivaiheisen pyrolyysiprosessin mallintaminen
2015
Työssä rakennetun mallin avulla määritettiin kolmivaiheisen hitaan pyrolyysiprosessin massa- ja energiavirrat. Mallissa reaktoriin syötettiin 2 kg tuoretta mäntyä, josta kuivausvaiheen jälkeen saatiin tuotteena 1 kg kuivaa puuta. Lämpötilassa 260 °C suoritetun torrefioinnin kiintosaanto oli 0,84 kg torrefiointiöljyn 0,13 kg ja kaasujen 0,04 kg. Hapan torrefiointiöljy sekä torrefiointikaasut johdettiin ulos prosessista ja torrefioitu puu pyrolysoitiin 450 °C:ssa, jolloin muodostui biohiiltä 0,28 kg, pyrolyysiöljyä 0,35 kg ja pyrolyysikaasuja 0,37 kg kiloa torrefioitua puuta kohti. Kuivausvaihe kulutti energiaa 3260 kJ/kg-tuore puu ja torrefiointi 619 kJ/kg-kuiva puu. Pyrolyysivaihe sen sijaa…
A survey on algebraic dilatations
2023
In this text, we wish to provide the reader with a short guide to recent works on the theory of dilatations in Commutative Algebra and Algebraic Geometry. These works fall naturally into two categories: one emphasises foundational and theoretical aspects and the other applications to existing theories.
Orbitotomía supero medial: nuevos límites en el abordaje endonasal expandido transetmoidal
2015
Introducción: Los límites de los abordajes endonasales endoscópicos expandidos (AEEE) no están delimitados y continúan en constante evolución. El límite de la extensión lateral en el plano coronal del AEEE transetmoidal descrito hasta el momento viene determinado por la unión del techo de las fóveas etmoidales con la lámina papirácea. Objetivos: Este trabajo se basa en la hipótesis fundamental de que la resección de lesiones situadas en la base craneal anterior, concretamente en la porción formada por el hueso frontal y asentadas más allá de las láminas papiráceas, pueden ser abordadas de forma completamente endonasal endoscópica. La hipótesis operativa considera que es posible mediante la …
Three-dimensional core-collapse supernovae with complex magnetic structures: I. Explosion dynamics
2021
Magnetic fields can play a major role in the dynamics of outstanding explosions associated to violent events such as GRBs and hypernovae, since they provide a natural mechanism to harness the rotational energy of the central proto-neutron star and power relativistic jets through the stellar progenitor. As the structure of such fields is quite uncertain, most numerical models of MHD-driven core-collapse supernovae consider an aligned dipole as initial magnetic field, while the field's morphology can actually be much more complex. We present three-dimensional simulations of core-collapse supernovae with more realistic magnetic structures, such as quadrupolar fields and, for the first time, an…
The impact of non-dipolar magnetic fields in core-collapse supernovae
2019
The magnetic field is believed to play an important role in at least some core-collapse supernovae if its magnitude reaches $10^{15}\,\rm{G}$, which is a typical value for a magnetar. In the presence of fast rotation, such a strong magnetic field can drive powerful jet-like explosions if it has the large-scale coherence of a dipole. The topology of the magnetic field is, however, probably much more complex with strong multipolar and small-scale components and the consequences for the explosion are so far unclear. We investigate the effects of the magnetic field topology on the dynamics of core-collapse supernovae and the properties of forming proto-neutron star (PNS) by comparing pre-collap…
AI Ethics in Industry: A Research Framework
2019
Artificial Intelligence (AI) systems exert a growing influence on our society. As they become more ubiquitous, their potential negative impacts also become evident through various real-world incidents. Following such early incidents, academic and public discussion on AI ethics has highlighted the need for implementing ethics in AI system development. However, little currently exists in the way of frameworks for understanding the practical implementation of AI ethics. In this paper, we discuss a research framework for implementing AI ethics in industrial settings. The framework presents a starting point for empirical studies into AI ethics but is still being developed further based on its pr…