5,298 research outputs found
Using FPGA for visuo-motor control with a silicon retina and a humanoid robot
The address-event representation (AER) is a
neuromorphic communication protocol for transferring
asynchronous events between VLSI chips. The event
information is transferred using a high speed digital parallel
bus. This paper present an experiment based on AER for
visual sensing, processing and finally actuating a robot. The
AER output of a silicon retina is processed by an AER filter
implemented into a FPGA to produce a mimicking behaviour
in a humanoid robot (The RoboSapiens V2). We have
implemented the visual filter into the Spartan II FPGA of the
USB-AER platform and the Central Pattern Generator (CPG)
into the Spartan 3 FPGA of the AER-Robot platform, both
developed by authors.Unión Europea IST-2001-34124 (CAVIAR)Ministerio de Ciencia y Tecnología TIC-2003-08164-C03-0
Roper Excitation in Alpha-Proton Scattering
We study the Roper excitation in the reaction. We consider
all processes which may be relevant in the Roper excitation region, namely,
Roper excitation in the target, Roper excitation in the projectile, and double
excitation processes. The theoretical investigation shows that the
Roper excitation in the proton target mediated by an isoscalar exchange is the
dominant mechanism in the process. We determine an effective isoscalar
interaction by means of which the experimental cross section is well
reproduced. This should be useful to make predictions in related reactions and
is a first step to construct eventually a microscopic
transition potential, for which the present reaction does not offer enough
information.Comment: Latex 17 pages; figures available by request; Phys. Rev. C in prin
Risk profile indicators and Spanish banks’ probability of default from a regulatory approach
This paper analyses the relationships between the traditional bank risk profile indicators
and a new measure of banks’ probability of default that considers the Basel regulatory framework.
First, based on the SYstemic Model of Bank Originated Losses (SYMBOL), we calculated the individual
probabilities of default (PD) of a representative sample of Spanish credit institutions during the
period of 2008–2016. Then, panel data regressions were estimated to explore the influence of the risk
indicators on the PD. Our findings on the Spanish banking system could be important to regulatory
and supervisory authorities. First, the PD based on the SYMBOL model could be used to analyse bank
risk from a regulatory approach. Second, the results might be useful for designing new regulations
focused on the key factors that affect the banks’ probability of default. Third, our findings reveal that
the emphasis on regulation and supervision should differ by type of entity
Factors Influencing the European Bank’s Probability of Default: An Application of SYMBOL Methodology
This paper analyses European banks’ probability of default (PD) by estimating a new measure that is based on the SYstemic Model of Bank Originated Losses (SYMBOL). First, we calculate the individual PD of a sample of European credit institutions during the period of 2011–2016. Then, dynamic panel data models are estimated to analyse the influence of several bank-specific and macroeconomic variables on the PD. We conclude that capital adequacy, liquidity, asset quality and profitability indicators influence the European banks’ PD. The macroeconomic scenario, the industry concentration and the size of banks also appear to have an impact on their risk.Fundación de la Universidad de Cantabria para el Estudio y la Investigación del sector Financiero (UCEIF) y el Banco Santander
Microstructure and precipitation behavior of advanced RAFM steels for high-temperature applications on fusion reactors
The composition of new eigth 9% Cr reduced activation ferritic/martensitioc steels (RAFMs) has been finely tuned in order to increase the amount of fine MX precipitates and reduce coarse MC carbides through the application of thermomechanical treatments. The microstructural investigations by TEM/STEM and EELS have shown MC, MX (CrN), and MX (Ta, V, and Ti-rich) precipitates after tempering at 750 °C/2 h. Higher N contens (0.04–0.03 wt%) seems to favored MX precipitation over MX with V contents round 0.2 wt%. MX-Ti rich presents sizes larger than MX (Ta or V rich). EELS anlysis have shown that the MX (Ta, V and Ti rich) precipitated after tempering at 750 °C/2 h are mainly carbo-nitrides. Composition, size, number density and carbon and nitrogen content on MX and MX is discussed in terms of the composition of each Alloy
Transient Propagation and Scattering of Quasi-Rayleigh Waves in Plates: Quantitative comparison between Pulsed TV-Holography Measurements and FC(Gram) elastodynamic simulations
We study the scattering of transient, high-frequency, narrow-band
quasi-Rayleigh elastic waves by through-thickness holes in aluminum plates, in
the framework of ultrasonic nondestructive testing (NDT) based on full-field
optical detection. Sequences of the instantaneous two-dimensional (2-D)
out-of-plane displacement scattering maps are measured with a self-developed
PTVH system. The corresponding simulated sequences are obtained by means of an
FC(Gram) elastodynamic solver introduced recently, which implements a full
three-dimensional (3D) vector formulation of the direct linear-elasticity
scattering problem. A detailed quantitative comparison between these
experimental and numerical sequences, which is presented here for the first
time, shows very good agreement both in the amplitude and the phase of the
acoustic field in the forward, lateral and backscattering areas. It is thus
suggested that the combination of the PTVH system and the FC(Gram)
elastodynamic solver provides an effective ultrasonic inspection tool for
plate-like structures, with a significant potential for ultrasonic NDT
applications.Comment: 46 pages, 16 figures, corresponding author Jos\'e Carlos
L\'opez-V\'azquez, [email protected]. Changes: 1st, 4th, 5th paragraphs
(intro), 3rd, 4th paragraphs (sec. 4); [59-60] cited only in appendixes; old
ref. [52] removed; misprints corrected in the uncertainty of c_L (subsec.
3.1), citation to fig. 10 (sec. 4), size of images (caption fig.15);
reference to Lam\'e constants removed in subsec. 3.
Point defects on graphene on metals
Understanding the coupling of graphene with its local environment is critical
to be able to integrate it in tomorrow's electronic devices. Here we show how
the presence of a metallic substrate affects the properties of an atomically
tailored graphene layer. We have deliberately introduced single carbon
vacancies on a graphene monolayer grown on a Pt(111) surface and investigated
its impact in the electronic, structural and magnetic properties of the
graphene layer. Our low temperature scanning tunneling microscopy studies,
complemented by density functional theory, show the existence of a broad
electronic resonance above the Fermi energy associated with the vacancies.
Vacancy sites become reactive leading to an increase of the coupling between
the graphene layer and the metal substrate at these points; this gives rise to
a rapid decay of the localized state and the quenching of the magnetic moment
associated with carbon vacancies in free-standing graphene layers
Regulatory estimates for defaulted exposures: A case study of Spanish mortgages
The capital requirements derived from the Basel Accord were issued with the purpose of
deploying a transnational regulatory framework. Further regulatory developments on risk measurement
is included across several documents published both by the European Banking Authority and
the European Central Bank. Among others, the referred additional documentation focused on the
models’ estimation and calibration for credit risk measurement purposes, especially the Advanced
Internal-Ratings Based models, which may be estimated both for non-defaulted and defaulted assets.
A concrete proposal of the referred defaulted exposures models, namely the Expected Loss Best Estimate
(ELBE) and the Loss Given Default (LGD) in-default, is presented. The proposed methodology
is eventually calibrated on the basis of data from the mortgage’s portfolios of the six largest financial
institutions in Spain. The outcome allows for a comparison of the risk profile particularities attached
to each of the referred portfolios. Eventually, the economic sense of the results is analyzed.Regional Government of Andalusia, Spain (Research Group SEJ-555)
Forecasting for regulatory credit loss derived from the COVID-19 pandemic: A machine learning approach
The economic onslaught of the COVID-19 pandemic has compromised the risk management of financial institutions. The consequences related to such an unprecedented situation are difficult to foresee with certainty using traditional methods. The regulatory credit loss attached to defaulted mortgages, so-called expected loss best estimate (ELBE), is forecasted using a machine learning technique. The projection of two ELBEs for 2022 and their comparison are presented. One accounts for the outbreak’s impact, and the other presumes the nonexistence of the pandemic. Then, it is concluded that the referred crisis surely adversely affects said high-risk portfolios. The proposed method has excellent performance and may serve to estimate future expected and unexpected losses amidst any event of extraordinary magnitud
- …