Sampling Theorem and Discrete Fourier Transform on the Hyperboloid

Using Coherent-State (CS) techniques, we prove a sampling theorem for holomorphic functions on the hyperboloid (or its stereographic projection onto the open unit disk $\mathbb D_1$), seen as a homogeneous space of the pseudo-unitary group SU(1,1). We provide a reconstruction formula for bandlimited functions, through a sinc-type kernel, and a discrete Fourier transform from $N$ samples properly chosen. We also study the case of undersampling of band-unlimited functions and the conditions under which a partial reconstruction from $N$ samples is still possible and the accuracy of the approximation, which tends to be exact in the limit $N\to\infty$.Comment: 22 pages, 2 figures. Final version published in J. Fourier Anal. App

Equivalent Circuit Modelling of Non-Symmetric Reciprocal Lossy Electromagnetic Structures

Lattice-network-based equivalent circuits of lossy symmetric reciprocal electromagnetic structures have shown superior performance when compared to other topologies like the T- or PI- networks. This is due to the realizability of their elements and the orthogonal-mode decomposition, which, in most cases, provides a deep physical insight into the behaviour of the modelled structure. The aim of this contribution is to provide a short description of these equivalent circuits and to compare their performances by modelling a misaligned complementary strip-slot element.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Marie Sklodowska-Curie grant agreement No 706334. Spanish Ministerio de Economía y Competitividad and the European Regional Development Funds under Grants TEC2016-76070-CR3-2-R and TEC2016-76070-CR3-3-R (ADDMATE)

On the Phase Response and Radiation Efficiency of the Complementary Strip-Slot as an Array Element

The complementary strip-slot element is a broadlymatched microstrip radiator that has been used to design innovative series-fed arrays. It consists of a microstrip series-fed slot that have its complementary stub on the layer of the microstrip and aligned to the slot. In this contribution, the influence of the strip and slot geometry on its performance is studied through the analysis of four different designs. The obtained results highlight the possibility of controlling the radiation efficiency or the phase response, without compromising the broad matching. Therefore, potential series-fed arrays built with this element can exploit this feature to set the magnitude and phase of the excitations with certain flexibility.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work was supported by the Spanish Ministerio de Ciencia e Innovaci ´on (Programa Consolider-Ingenio 2010) under Grant CSD2008-00066, EME

Entornos Virtuales, potencialidades y limitaciones para la Extensión Universitaria

The purpose of this research work is to analyze the potentialities and limitations offered by Virtual Environments such as science and technology products for University Extension in the University of Guantánamo. To carry out this investigation were applied methods from the theoretical and empirical level that allowed corroborating the problem under study. It also offers a definition of Virtual Environments according to the new context where they apply.El presente trabajo investigativo tiene como objetivo analizar las potencialidades y limitaciones que ofrecen los Entornos Virtuales como productos de la ciencia y la tecnología para la Extensión Universitaria en la Universidad de Guantánamo. Para llevar a cabo esta investigación se emplearon métodos del nivel teórico y empírico que permitieron corroborar la problemática objeto de estudio. Se ofrece además una definición de Entornos Virtuales acorde al nuevo contexto donde estos se aplican

A New Multi-Rate Clock and Data Recovery Circuit

A new bit rate adaptive clock and data recovery circuit able to operate in a range from 3.125 Mb/s to 2.5 Gb/s is presented in this work. It is designed in a standard CMOS technology, fed with a single supply voltage of 1.8 V and has a maximum power consumption of 140 mW

“COMPORTAMIENTO DEL TRASTORNO POR DÉFICIT DE ATENCIÓN E HIPERACTIVIDAD Y DE LA DISCAPACIDAD MOTORA EN PACIENTES DEL CENTRO DE REHABILITACIÓN INFANTIL DE LA SECRETARIA DE LA DEFENSA NACIONAL DURANTE EL PERIODO 2009-2012”

El trastorno por déficit de atención e hiperactividad (TDAH), es un trastorno neuropsiquiátrico que viene definido por tres síntomas principales: Inatención, impulsividad e hiperactividad, ésta no siempre presente. Como resultado, se producen conductas inadecuadas para la edad de desarrollo del individuo y problemas de aprendizaje

Almost Complete Coherent State Subsystems and Partial Reconstruction of Wave Functions in the Fock-Bargmann Phase-Number Representation

We provide (partial) reconstruction formulas and discrete Fourier transforms for wave functions in standard Fock-Bargmann (holomorphic) phase-number representation from a finite number $N$ of phase samples $\{\theta_k=2\pi k/N\}_{k=0}^{N-1}$ for a given mean number $p$ of particles. The resulting Coherent State (CS) subsystem ${\cal S}=\{|z_k=p^{1/2}e^{i\theta_k}>\}$ is complete (a frame) for truncated Hilbert spaces (finite number of particles) and reconstruction formulas are exact. For an unbounded number of particles, ${\cal S}$ is "almost complete" (a \textit{pseudo-frame}) and partial reconstruction formulas are provided along with an study of the accuracy of the approximation, which tends to be exact when $p<N$ and/or $N\to\infty$.Comment: 20 pages, 3 figures. Typos correcte

A reconfigurable radio-frequency converter IC in 0.18 µm CMOS

This work presents a reconfigurable RF converter for DVB-T television applications using triple-play over GPON. The system takes the DVB-T input, a wavelength division multiplexing (WDM) signal with spectral inversion in the range from 47 MHz to 1000 MHz, up-converts its frequency to the band-pass of a highly selective surface-acoustic wave (SAW) filter centered at 1.3 GHz, and then down-converts it so that it is compatible with the antenna input of conventional television sets. The designed RF converter incorporates two pairs of frequency synthesizer and mixer, based, respectively, on an integer-N phase-locked loop (PLL) with two LC-tank VCOs with 128 coarse tuning bands in the range from 1.35 GHz to 2.7 GHz, and a double-balanced Gilbert cell, modified for better impedance matching and improved linearity. It is fed with regulated supplies compensated in temperature and programmed by an I2 C interface operating on five 16-bit registers. This work presents the experimental characterization of the whole system plus selected cells for stand-alone testing, which have been fabricated in a 0.18 µm CMOS process

High accuracy 235 U(n,f) data in the resonance energy region

The 235U neutron-induced cross section is widely used as reference cross section for measuring other fission cross sections, but in the resonance region it is not considered as an IAEA standard because of the scarce experimental data covering the full region. In this work, we deal with a new analysis of the experimental data obtained with a detection setup based on parallel plate ionization chambers (PPACs) at the CERN n_TOF facility in the range from 1 eV to 10 keV. The relative cross section has been normalised to the IAEA value in the region between 7.8 and 11 eV, which is claimed as well-known. Comparison with the ENDF/B-VII evaluation and the IAEA reference file from 100 eV to 10 keV are provide

β-decay half-lives and β-delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N = 126

Background: There have been measurements on roughly 230 nuclei that are β-delayed neutron emitters. They range from 8 He up to 150La. Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has been measured beyond A = 150. Therefore, new data are needed, particularly in the region of heavy nuclei around N = 126, in order to guide theoretical models and help understand the formation of the third r-process peak at A ∼ 195. Purpose: To measure both β-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb, and Bi isotopes beyond N = 126. Method: Ions of interest were produced by fragmentation of a 238U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) was used to measure ion implants and β decays. An array of 30 3 He tubes embedded in a polyethylene matrix (BELEN) was used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time correlations. The latter were analyzed with an analytical model and results for the half-lives and neutron-branching ratios were derived by using the binned maximum-likelihood method. Results: Twenty new β-decay half-lives are reported for 204−206Au, 208–211Hg, 211–216Tl, 215–218Pb, and 218–220Bi, nine of them for the first time. Neutron emission probabilities are reported for 210,211Hg and 211–216Tl. Conclusions: The new β-decay half-lives are in good agreement with previous measurements on nuclei in this region. The measured neutron emission probabilities are comparable to or smaller than values predicted by global models such as relativistic Hartree Bogoliubov plus the relativistic quasi-particle random phase approximation (RHB + RQRPA).Spanish Ministerio de Economía y Competitividad-FPA2011- 28770-C03-03, FPA2008-04972-C03-3, AIC-D2011-0705, FPA2011-24553, FPA2008-6419, FPA2010-17142, FPA2014-52823-C2-1-P, FPA2014- 52823-C2-2-P, and CPAN CSD-2007-00042 (Ingenio2010)Program Severo Ochoa-SEV-2014-0398German Helmholtz Association (Young Investigators)-VH-NG 627 (LISA-Lifetime Spectroscopy for Astrophysics)Nuclear Astrophysics Virtual Institute-VH-VI-417German Bundesministerium für Bildung und Forschung-06MT7178 / 05P12WOFNFSpanish Nuclear Security Council (CSN)-Catedra ArgosUK Science & Technology Facilities Council (STFC)-ST/F012012/