9,753 research outputs found
Beyond Intent: Technology Adoption and Appropriation by University Staff
In this paper, we propose a model for understanding adoption and
appropriation of technology. We describe a university-wide
system that is designed for faculty and students, but which has
been adopted by staff, followed by a survey study and some
preliminary results
Holographic studies of Einsteinian cubic gravity
Einsteinian cubic gravity provides a holographic toy model of a
nonsupersymmetric CFT in three dimensions, analogous to the one defined by
Quasi-topological gravity in four. The theory admits explicit non-hairy AdS
black holes and allows for numerous exact calculations, fully nonperturbative
in the new coupling. We identify several entries of the AdS/CFT dictionary for
this theory, and study its thermodynamic phase space, finding interesting new
phenomena. We also analyze the dependence of R\'enyi entropies for disk regions
on universal quantities characterizing the CFT. In addition, we show that
is given by a non-analytic function of the ECG coupling, and that the
existence of positive-energy black holes strictly forbids violations of the KSS
bound. Along the way, we introduce a new method for evaluating Euclidean
on-shell actions for general higher-order gravities possessing second-order
linearized equations on AdS. Our generalized action involves the very
same Gibbons-Hawking boundary term and counterterms valid for Einstein gravity,
which now appear weighted by the universal charge controlling the
entanglement entropy across a spherical region in the CFT dual to the
corresponding higher-order theory.Comment: 59 pages, 7 figures, 1 table; v4: typos fixe
Primordial dark energy from a condensate of spinors in a 5D vacuum
We explore the possibility that the expansion of the universe can be driven
by a condensate of spinors which are free of interactions on a 5D relativistic
vacuum defined on an extended de Sitter spacetime which is Riemann-flat. The
extra coordinate is considered as noncompact. After making a static foliation
on the extra coordinate, we obtain an effective 4D (inflationary) de Sitter
expansion which describes an inflationary universe. We found that the
condensate of spinors here studied could be an interesting candidate to explain
the presence of dark energy in the early universe. The dark energy density
which we are talking about is poured into smaller sub-horizon scales with the
evolution of the inflationary expansion.Comment: Accepted in Advances in High Energy Physic
Near-threshold properties of the electronic density of layered quantum-dots
We present a way to manipulate an electron trapped in a layered quantum dot
based on near-threshold properties of one-body potentials. We show that
potentials with a simple global parameter allows the manipulation of the wave
function changing its spatial extent. This phenomenon seems to be fairly
general and could be implemented using current quantum-dot quantum wells
technologies and materials if a proper layered quantum dot is designed. The
layered quantum dot under consideration is similar to a quantum-dot quantum
well device, i.e. consists of a spherical core surrounded by successive layers
of different materials. The number of layers and the constituent material are
chosen to highlight the near-threshold properties.
In particular we show that the near-threshold phenomena can be observed using
an effective mass approximation model that describes the layered quantum dot
which is consistent with actual experimental parameters.Comment: 15 pages, 6 figures, regular articl
A viral system to optimise the daily drayage problem
The intermodal transport chain can become more efficient by means of a good organisation of the drayage movements. Drayage in intermodal container terminals involves the pick up or delivery of containers at customer locations, and the main objective is normally the assignment of transportation tasks to the different vehicles, often with the presence of time windows. This paper focuses on a new approach to tackle the daily drayage problem by the use of viral system (VS). VS is a novel bio-inspired approach that makes use of a virus-infection biological analogy that is producing very satisfactory results when dealing with complex problems with huge feasibility region.Unión Europea TEC2013-47286-C3-3-
Quantum control of a model qubit based on a multi-layered quantum dot
In this work we present a model qubit whose basis states are eigenstates of a
multi-layered quantum dot. We show that the proper design of the quantum dot
results in qubit states that have excellent dynamical properties when a
time-dependent driving is applied to it. In particular, it is shown that a
simple sinusoidal driving is sufficient to obtain good quality Rabi
oscillations between the qubit states. Moreover, the switching between states
can be performed with very low leakage, even under off-resonance conditions. In
this sense, the quantum control of the qubit is robust under some perturbations
and achieved with simple means.Comment: 19 pages, 8 figure
The Vectorial -Calculus
We describe a type system for the linear-algebraic -calculus. The
type system accounts for the linear-algebraic aspects of this extension of
-calculus: it is able to statically describe the linear combinations
of terms that will be obtained when reducing the programs. This gives rise to
an original type theory where types, in the same way as terms, can be
superposed into linear combinations. We prove that the resulting typed
-calculus is strongly normalising and features weak subject reduction.
Finally, we show how to naturally encode matrices and vectors in this typed
calculus.Comment: Long and corrected version of arXiv:1012.4032 (EPTCS 88:1-15), to
appear in Information and Computatio
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