510 research outputs found

    High Gain Amplifier with Enhanced Cascoded Compensation

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    A two-stage CMOS operational amplifier with both, gain-boosting and indirect current feedback frequency compensation performed by means of regulated cascode amplifiers, is presented. By using quasi-floating-gate transistors (QFGT) the supply requirements, the number of capacitors and the size of the compensation capacitors respect to other Miller schemes are reduced. A prototype was fabricated using a 0.5 μm technology, resulting, for a load of 45 pF and supply voltage of 1.65 V, in open-loop-gain of 129 dB, 23 MHz of gain-bandwidth product, 60o phase margin, 675 μW power consumption and 1% settling time of 28 ns

    Iuriservice : un FAQ Inteligente para los jueces en su primer destino

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    En esta presentación describimos el uso de ontologías legales como base para la mejora del soporte para jueces. El uso de la tecnología de procesamiento de lenguaje natural permite obtener respuestas a los jóvenes jueces en tiempo real y mejorar así su trabajo día a día.We present an intelligent FAQ system for junior judges that intensively uses the ontology and allows a free text input for querying. We describe the use of legal ontologies as a basis to improve IT support for professional judges. As opposed to most legal ontologies designed so far, which are mostly based on dogmatic and normative knowledge, we emphasize the importance of professional knowledge and experience as an important pillar for constructing the ontolog

    Exploration of the treatment of fish-canning industry effluents by aqueous-phase reforming using Pt/C catalysts

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    In the current work, an exploratory study on the application of catalytic aqueous phase reforming (APR) to the treatment of fish-canning wastewater was performed for the first time. Pt/C (3%, w) catalysts were supported on different commercial carbon supports (two activated carbons and a carbon black) and tested in the APR of tuna-cooking wastewater. The effect of the supports and the reaction systems (batch vs. semi-continuous) on the performance of the catalysts was tested. The stability of the catalysts upon 3 successive reuse cycles was checked. TOC and COD removal ranged within 45-60%, which was ascribed to adsorption on the supports, hydrothermal carbonization and APR. The percentage of valuable gases (H2 and alkanes) reached up to 18% of the gas production showing the potential of APR for the valorization and treatment of wastewater. The production of gases is affected by the high chloride, acetate and phosphate concentrations, which may provoke catalyst deactivation. The use of a catalyst with a basic support significantly increased the production of gases and the H2 percentage in the gas fraction. Gas production was higher in semi-continuous compared to batch operation, maybe because the withdrawn gas displaces the reaction towards the products. The percentage of alkanes in the gas phase decreased upon successive catalyst reuse cycles at the expense of H2, which is probably due to sintering of Pt nanoparticles with the corresponding decrease of the number of low-coordinated Pt sites promoting methanation reactionsThe authors greatly appreciate financial support from Spanish MINECO (CTQ2015-65491-R). A. S. Oliveira thanks the Spanish MINECO for a research grant (BES-2016-077244

    Group Approach to the Quantization of the P\"oschl-Teller dynamics

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    The quantum dynamics of a particle in the Modified P\"oschl-Teller potential is derived from the group SL(2,R)SL(2,R) by applying a Group Approach to Quantization (GAQ). The explicit form of the Hamiltonian as well as the ladder operators is found in the enveloping algebra of this basic symmetry group. The present algorithm provides a physical realization of the non-unitary, finite-dimensional, irreducible representations of the SL(2,R)SL(2,R) group. The non-unitarity manifests itself in that only half of the states are normalizable, in contrast with the representations of SU(2) where all the states are physical.Comment: 17 pages, LaTe

    Corrosion resistance of anodic layers grown on 304L stainless steel at different anodizing times and stirring speeds

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    Different chemical and physical treatments have been used to improve the properties and functionalities of steels. Anodizing is one of the most promising treatments, due to its versatility and easy industrial implementation. It allows the growth of nanoestructured oxide films with interesting properties able to be employed in different industrial sectors. The present work studies the influence of the anodizing time (15, 30, 45 and 60 min), as well as the stirring speed (0, 200, 400, and 600 rpm), on the morphology and the corrosion resistance of the anodic layers grown in 304L stainless steel. The anodic layers were characterized morphologically, compositionally, and electrochemically, in order to determine the influence of the anodization parameters on their corrosion behavior in a 0.6 mol L-1 NaCl solution. The results show that at 45 and 60 min anodizing times, the formation of two microstructures is favored, associated with the collapse of the nanoporous structures at the metal-oxide interphace. However, both the stirring speed and the anodizing time have a negligeable effect on the corrosion behavior of the anodized 304L SS samples, since their electrochemical values are similar to those of the non-anodized ones

    Seasonal temperature trends on the Spanish mainland: A secular study (1916–2015)

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    Trends in seasonal mean values of maximum and minimum temperature are analysed in the Spanish mainland from the new MOTEDAS_century database. This new data set has been developed combining the digitalized archives from the Spanish Meteorological Agency (AEMET) with information retrieved from Annual Books published by the former Meteorological Agency dating back to 1916, and covers the period 1916–2015. In all four seasons, mean seasonal temperature of maximum (Tmax) and minimum (Tmin) increased. The raising occurred in two main pulses separated by a first pause around the middle of the 20th century, but differed among seasons and also between maximum and minimum temperature. Analysis of the percentage of land affected by significant trends in maximum temperature reveals two increasing phases in spring and summer for Tmax, and in spring, summer, and autumn for Tmin. However, winter Tmax only rose during the recent decades, and autumn Tmax in the first decades. Negative significant trends were found in extended areas in spring Tmax, and in spring, autumn, and summer Tmin, confirming the first pause around the 1940's–1960's. Trends of seasonal mean values of Tmax and Tmin are not significant for at least the last 25–35 years of the study period, depending on the season. The areas under significant positive trend are usually more extended for Tmin than Tmax at any season and period. Areas with significant trend expand and contract in time according to two spatial gradients: south-east to north-west (east-west) for Tmax, and west to east for Tmin. We hypothesize a relationship between atmospheric prevalent advection and relief as triggering factors to understand spatial and temporal differences in seasonal temperatures at regional scale during the 20th century in the Iberian Peninsula

    Síndrome de Ogilvie

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    El síndrome de Ogilvie es una pseudo obstrucción funcional aguda del colon, de etiología desconocida, que se presenta por lo general en pacientes de edad avanzada, hospitalizados por enfermedades neurológicas, cardiovasculares, postoperatorios neuroquirúrgico, ginecológico, abdominal u ortopédico, sepsis, quemaduras y traumatismos. Se caracteriza por una dilatación progresiva del colon que puede evolucionar hacia la isquemia, necrosis, perforación y muerte.Facultad de Ciencias Médica

    A CMOS Morlet Wavelet Generator

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    The design and characterization of a CMOS circuit for Morlet wavelet generation is introduced. With the proposed Morlet wavelet circuit, it is possible to reach a~low power consumption, improve standard deviation (σ) control and also have a small form factor. A prototype in a double poly, three metal layers, 0.5 µm CMOS process from MOSIS foundry was carried out in order to verify the functionality of the proposal. However, the design methodology can be extended to different CMOS processes. According to the performance exhibited by the circuit, may be useful in many different signal processing tasks such as nonlinear time-variant systems

    Síndrome de Ogilvie

    Get PDF
    El síndrome de Ogilvie es una pseudo obstrucción funcional aguda del colon, de etiología desconocida, que se presenta por lo general en pacientes de edad avanzada, hospitalizados por enfermedades neurológicas, cardiovasculares, postoperatorios neuroquirúrgico, ginecológico, abdominal u ortopédico, sepsis, quemaduras y traumatismos. Se caracteriza por una dilatación progresiva del colon que puede evolucionar hacia la isquemia, necrosis, perforación y muerte.Facultad de Ciencias Médica
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