Verification of RNN-based neural agent-environment systems

We introduce agent-environment systems where the agent is stateful and executing a ReLU recurrent neural network. We define and study their verification problem by providing equivalences of recurrent and feed-forward neural networks on bounded execution traces. We give a sound and complete procedure for their verification against properties specified in a simplified version of LTL on bounded executions. We present an implementation and discuss the experimental results obtained

The strange-quark mass from QCD sum rules in the pseudoscalar channel

QCD Laplace transform sum rules, involving the axial-vector current divergences, are used in order to determine the strange quark mass. The two-point function is known in QCD up to four loops in perturbation theory, and up to dimension-six in the non-perturbative sector. The hadronic spectral function is reconstructed using threshold normalization from chiral symmetry, together with experimental data for the two radial excitations of the kaon. The result for the running strange quark mass, in the $\bar{MS}$ scheme at a scale of 1 ${GeV}^{2}$ is: ${\bar m}_{s}(1 GeV^{2}) = 155 \pm 25 {MeV}$.Comment: 10 pages. Latex file. 2 Figures obtained from author CAD upon reques

The data privacy issue. Provision 20/2015 of the Ministry of Justice and Human Rights on Personal Data Protection

The robotic technology has generated a revolution in the activity of aviation. One of the most important advances of the XXI century has been given from the massive incursion on the private market of the Remotely Piloted Aircraft Systems (RAPS or drones). These vehicles evolve day to day and at present they are capable of accessing to the most remote places being able of capturing information in such a way that they may go unnoticed during their task. The legislation noting the possibility that the privacy of the people is seriously affected by the activity of the RAPS´s, is forced to regulate their operations. In this chapter we will analyze the regulations that the Argentine Republic has designed in order to protect the personal data of the Human Persons that may be affected by the action of a RAPS that carries a device so as to capture data. We will depart from the law 25.326 as general legislation of personal data protection and we will review the European provisions on the subject that have helped as background for the national regulation.La tecnología robótica ha generado una revolución en la actividad de la aviación. Uno de los avances más importantes de este siglo XXI se ha dado a partir de la incursión masiva en el comercio privado de los Vehículos Aéreos No Tripulados (VANT o drones). Estos vehículos evolucionan día a día y en la actualidad son capaces de acceder a los sitios más recónditos pudiendo capturar información de forma tal que pueden pasar desapercibidos durante su tarea. La legislación advirtiendo la posibilidad de que la privacidad de las personas se vea seriamente afectada por la actividad de los VANT´s, se encuentra forzada a regular su operatoria. En este capítulo analizaremos la normativa que la República Argentina ha diseñado para proteger los datos personales de las Personas Humanas que pueden verse afectadas por la acción de un VANT que transporte un dispositivo para capturar datos. Partiremos de la ley 25.326 como legislación general de protección de datos personales y repasaremos las disposiciones europeas sobre la materia que han servido de antecedentes para la regulación nacional

Probabilistic data association: the orbit set

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Metastable precursors during the oxidation of the Ru(0001) surface

Using density-functional theory, we predict that the oxidation of the Ru(0001) surface proceeds via the accumulation of sub-surface oxygen in two-dimensional islands between the first and second substrate layer. This leads locally to a decoupling of an O-Ru-O trilayer from the underlying metal. Continued oxidation results in the formation and stacking of more of these trilayers, which unfold into the RuO_2(110) rutile structure once a critical film thickness is exceeded. Along this oxidation pathway, we identify various metastable configurations. These are found to be rather close in energy, indicating a likely lively dynamics between them at elevated temperatures, which will affect the surface chemical and mechanical properties of the material.Comment: 11 pages including 9 figures. Submitted to Phys. Rev. B. Related publications can be found at http://www.fhi-berlin.mpg.de/th/paper.htm

Stability of sub-surface oxygen at Rh(111)

Using density-functional theory (DFT) we investigate the incorporation of oxygen directly below the Rh(111) surface. We show that oxygen incorporation will only commence after nearly completion of a dense O adlayer (\theta_tot = 1.0 monolayer) with O in the fcc on-surface sites. The experimentally suggested octahedral sub-surface site occupancy, inducing a site-switch of the on-surface species from fcc to hcp sites, is indeed found to be a rather low energy structure. Our results indicate that at even higher coverages oxygen incorporation is followed by oxygen agglomeration in two-dimensional sub-surface islands directly below the first metal layer. Inside these islands, the metastable hcp/octahedral (on-surface/sub-surface) site combination will undergo a barrierless displacement, introducing a stacking fault of the first metal layer with respect to the underlying substrate and leading to a stable fcc/tetrahedral site occupation. We suggest that these elementary steps, namely, oxygen incorporation, aggregation into sub-surface islands and destabilization of the metal surface may be more general and precede the formation of a surface oxide at close-packed late transition metal surfaces.Comment: 9 pages including 9 figure files. Submitted to Phys. Rev. B. Related publications can be found at http://www.fhi-berlin.mpg.de/th/paper.htm

The structure of epitaxial V2O3 films and their surfaces : a medium energy ion scattering study

Medium energy ion scattering, using 100 keV H+ incident ions, has been used to investigate the growth of epitaxial films, up to thicknesses of ~200 Å, of V2O3 on both Pd(111) and Au(111). Scattered-ion energy spectra provide a measure of the average film thickness and the variations in this thickness, and show that, with suitable annealing, the crystalline quality is good. Plots of the scattering yield as a function of scattering angle, so-called blocking curves, have been measured for two different incidence directions and have been used to determine the surface structure. Specifically, scattering simulations for a range of different model structures show poor agreement with experiment for half-metal (….V’O3V) and vanadyl (….V’O3V=O) terminations, with and without surface interlayer relaxations. However, good agreement with experiment is found for the modified oxygen-termination structure, first proposed by Kresse et al., in which a subsurface V half-metal layer is moved up into the outermost V buckled metal layer to produce a VO2 overlayer on the underlying V2O3, with an associated layer structure of ….O3VV’’V’O3