4,447 research outputs found

    Automatic construction of rules fuzzy for modelling and prediction of the central nervous system

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    The main goal of this work is to study the performance of CARFIR (Automatic Construction of Rules in Fuzzy Inductive Reasoning) methodology for the modelling and prediction of the human central nervous system (CNS). The CNS controls the hemodynamical system by generating the regulating signals for the blood vessels and the heart. The main idea behind CARFIR is to expand the capacity of the FIR methodology allowing it to work with classical fuzzy rules. CARFIR is able to automatically construct fuzzy rules starting from a set of pattern rules obtained by FIR. The new methodology preserves as much as possible the knowledge of the pattern rules in a compact fuzzy rule base. The prediction results obtained by the fuzzy prediction process of CARFIR methodology are compared with those of other inductive methodologies, i.e. FIR, NARMAX and neural networksPostprint (published version

    Annotation scheme for citation classification in scientific literature

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    El análisis de citas bibliográficas que usa variaciones de métodos de conteo provoca deformaciones en la evaluación del impacto. Para enriquecer el cálculo de los factores de impacto se necesita entender el tipo de influencia de los aportes de un investigador sobre el autor que los menciona. Para ello, se requiere realizar análisis de contenido del contexto de las citas que permita obtener su función, polaridad e influencia. El presente artículo trata sobre la definición de un esquema de anotación tendiente a la creación de un corpus de acceso público que sea la base de trabajo colaborativo en este campo, con miras al desarrollo de sistemas que permitan llevar adelante tareas de análisis de contenido con el objetivo planteado.Citation analysis that uses counting methods causes deformations in impact factor assessment. To enrich impact factor calculation is necessary to understand the kind of influence that the contributions of an author have over another´s work. For this purpose, it is required to perform citation content analysis to obtain its function, polarity and influence in a context within an article that mentioned it. In this paper, we focus in the definition of an annotation scheme aimed at creating a public access corpus that be the basis of collaborative work in this field, in order to develop citation content analysis to obtain criteria for impact evaluation

    Amplificación sísmica: Una aproximación por Elementos Finitos

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    En las páginas que siguen se presenta el estudio de uno de los más típicos problemas de dinámica estructural, cual es la obtención de la respuesta de una estructura excitada por un movimiento de la base. Este es un caso muy frecuente en ingeniería sísmica, donde el objeto del estudio puede ser el edificio (sometido a un movimiento en la cimentación) o un estrato de terreno sobre fondo rígido. Al objeto de facilitar un soporte intuitivo a la exposicióri, ésta se organiza en base al segundo de los casos citados (estrate en base rígida). La aproximación escogida, elementos finitos, pone de relieve una vez más la potencia y generalidad del método en lo que respecta a la formulación del sistema de equilibrio. La discusión se centra en un aspecto concreto del método: la elección de funciones de forma.The goal of this paper is to present the analysis of one of the most typical problems in dynamics: the response of a structure excited by a rigid-base motion. This is an usual case in seismic engineering, where the structure can be a building or a soil stratum lying on a rigid bed. In both cases the model will be the same but, in order to give a physical support to exposure, the later will be treated. The choosed approach, by finite elements, points up the power and the generality of that method with respect to equilibrium formulation. Emphasis is done over the choosing of shape functions.Peer Reviewe

    FPGA Implementation of an Adaptive Noise Canceller for Robust Speech Enhancement Interfaces

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    This paper describes the design and implementation results of an adaptive Noise Canceller useful for the construction of Robust Speech Enhancement Interfaces. The algorithm being used has very good performance for real time applications. Its main disadvantage is the requirement of calculating several operations of division, having a high computational cost. Besides that, the accuracy of the algorithm is critical in fixed-point representation due to the wide range of the upper and lower bounds of the variables implied in the algorithm. To solve this problem, the accuracy is studied and according to the results obtained a specific word-length has been adopted for each variable. The algorithm has been implemented for Altera and Xilinx FPGAs using high level synthesis tools. The results for a fixed format of 40 bits for all the variables and for a specific word-length for each variable are analyzed and discussed

    The relevance of grated inlets within surface drainage systems in the field of urban flood resilience. A review of several experimental and numerical simulation approaches

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    Urban drainage networks should be designed and operated preferably under open channel flow conditions without flux return, backwater, or overflows. In the case of extreme storm events, urban pluvial flooding is generated by the excess of surface runoff that could not be conveyed by pressurized sewer pipes, due to its limited capacity or, many times, due to the poor efficiency of surface drainage systems to collect uncontrolled overland flow. Generally, the hydraulic design of sewer systems is addressed more for underground networks, neglecting the surface drainage system, although inadequate inlet spacings and locations can cause dangerous flooding with rele-vant socio-economic impacts and the interruption of critical services and urban activities. Several experimental and numerical studies carried out at the Technical University of Catalonia (UPC) and other research institutions demonstrated that the hydraulic efficiency of inlets can be very low under critical conditions (e.g., high circulating overland flow on steep areas). In these cases, the hydraulic efficiency of conventional grated inlets and continuous transverse elements can be around 10–20%. Their hydraulic capacity, expressed in terms of discharge coefficients, shows the same criticism with values quite far from those that are usually used in several project practice phases. The grate clogging phenomenon and more intense storm events produced by climate change could further reduce the inlets’ performance. In this context, in order to improve the flood urban resilience of our cities, the relevance of the hydraulic behavior of surface drainage systems is clear

    Implementation of an autonomy support program during Physical Education lessons

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    El objetivo de este estudio es conocer los efectos de un programa basado en el soporte de autonomía a través de las clases de Educación Física sobre las necesidades psicológicas básicas, la regulación conductual y la percepción del estilo interpersonal del docente. Los participantes del estudio fueron 61 alumnos (25 chicos y 36 chicas) con edades comprendidas entre los 14 y los 17 años de edad (M = 14.97; DT = .85), pertenecientes a dos Centros Educativos españoles. Los estudiantes fueron divididos aleatoriamente en dos grupos (control y experimental). Los instrumentos utilizados fueron la Escala de Satisfacción de Necesidades Psicológicas Básicas, el Cuestionario de la Regulación Conductual en el Deporte y el Cuestionario de Estilo interpersonal del docente. Los profesores aplicaron en el grupo experimental el programa basado en el soporte de autonomía durante las clases de Educación Física en un total de ocho semanas. Los resultados indicaron diferencias estadísticamente significativas respecto a la relación con los demás (p<.01) y a la percepción del estilo autónomo del docente (p<.05), no encontrándose diferencias significativas respecto al resto de variables. Como conclusión principal indicar que un programa basado en el fomento de la autonomía, puede ser óptimo para el incremento de las relaciones entre los alumnos

    Toxicity of ZnO nanoparticles, ZnO bulk and ZnCl2 on earthworms in a spiked natural soil and toxicological effects of leachates on aquatic organisms

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    The present study assessed the uptake and toxicity of ZnO nanoparticles (NPs), ZnO bulk, and ZnCl2 salt in earthworms in spiked agricultural soils. In addition, the toxicity of aqueous extracts to Daphnia magna and Chlorella vulgaris was analyzed to determine the risk of these soils to the aquatic compartment. We then investigated the distribution of Zn in soil fractions to interpret the nature of toxicity. Neither mortality nor differences in earthworm body weight were observed compared with the control. The most sensitive end point was reproduction. ZnCl2 was notably toxic in eliminating the production of cocoons. The effects induced by ZnO-NPs and bulk ZnO on fecundity were similar and lower than those of the salt. In contrast to ZnO bulk, ZnO-NPs adversely affected fertility. The internal concentrations of Zn in earthworms in the NP group were greater than those in the salt and bulk groups, although bioconcentration factors were consistently <1. No relationship was found between toxicity and internal Zn amounts in earthworms. The results from the sequential extraction of soil showed that ZnCl2 displayed the highest availability compared with both ZnO. Zn distribution was consistent with the greatest toxicity showed by the salt but not with Zn body concentrations. The soil extracts from both ZnO-NPs and bulk ZnO did not show effects on aquatic organisms (Daphnia and algae) after short-term exposure. However, ZnCl2 extracts (total and 0.45-μm filtered) were toxic to Daphnia
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