1,433 research outputs found

    Detection of Major River Bed Changes in the River Ebro (north-eastern Spain)

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    Detection of major river bed changes in River Ebro (northeastern Spain

    An Overview of Organizational Research in Regional Development: Five Parallel Case Studies

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    In this paper we present proposals for a program of research into problems of complex organizations. The area of interest is organization for integrated regional development and our research will be based on five regional development cases undertaken in different circumstances in various parts of the world. Organization theory is not a unified field of research but includes many complementary approaches. The authors of this paper reflect this diversity. However, in designing these research proposals we find important points of commonality. The overall research conception based on a multiorganization approach is one such point. This is supported by a common definition of integrated regional development, which we pose for the purpose of organization study, and a common specification for the case descriptions, which form the first output stages of our program. However, in the analytic stages, which follow these descriptions, we see value in following somewhat different approaches. This diversity should strengthen the value of the final output. In this paper we cover generally the scope and purposes of the overall program. The scope of case descriptions is presented together with an outline of the questions which are addressed in the post-description analytic stages

    Factores de riesgo y consecuencias de las caídas en los residentes de un Centro Geriátrico Asistido.

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    Estudio Realizado sobre el fenómeno de las caídas con una muestro de 79 ancianos de un Centro Geriátrico Asistido para valorar la incidencia de determinados factores de riesgo intrínsecos y extrínsecos, así como sus consecuencias físicas y psíquicas (síndrome post-caída), evolución y tratamiento. El 80% de los ancianos sufrieron alguna caída. Las pruebas estadísticas realizadas mostraron que los ancianos que consumen benzodiacepinas e hipnóticos presentan mayor número de caídas que los que no consumen dichos fármacos, y lo mismo ocurre con el hecho de padecer demencia. La ocurrencia de las caídas también se estudió, mostrando los resultados una incidencia significativa del consumo de benzodiacepinas e hipnóticos (U=1119, p<0.001) y de neurolépticos (U=870, p<0.001). También inciden la demencia (U=937, p<0.0031 y Ios accidentes cerebro vasculares (U=347, p<0.007). El 15% de las caídas se debieron a enfermedades interrecurrentes o agudas, y un 5.1% terminaron en fractura. El 18.99% de los ancianos que sufrieron caídas mostraron el síndrome post-caída de modo objetivable

    Beryllium isotope variations recorded in the Ad´elie Basin, East Antarctica reflect Holocene changes in ice dynamics, productivity, and scavenging efficiency

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    The Ad´elie Basin is a relatively small (~1600 km2), semi-enclosed continental shelf bathymetric depression located adjacent to the Wilkes Subglacial Basin, a basin underlying a sector of the East Antarctic Ice Sheet that contains ~3–4 m sea level equivalent of ice. Located within the Ad´elie Basin is a ~184 m thick laminated sediment deposit, the Ad´elie Drift, ideal for examining regional changes in ice sheet and ocean dynamics. Here, we examine the ratio of reactive beryllium-10 to reactive beryllium-9 ((10Be/9Be)reac) in a marine sediment core obtained from the Ad´elie Drift to assess these changes during the Holocene epoch (11.7 ka BP to present). The (10Be/9Be)reac record provides insight into changes in freshwater input, primary productivity, and scavenging efficiency, while removing the influence of particle size on 10Be concentration. During the early Holocene, (10Be/9Be)reac ratios indicate increased meltwater discharge from ca. 11.7 to 10 ka BP, as grounded ice retreated from the Ad´elie Basin and adjacent bathymetric highs. After ~10 ka BP, beryllium isotopes are influenced by scavenging efficiency and dilution controlled by ocean currents and accumulation rate, operating alongside meltwater input, suggesting there are additional factors to consider when using (10Be/9Be)reac as a proxy for ice shelf cover and glacial dynamics.Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) Japan Society for the Promotion of ScienceGrants-in-Aid for Scientific Research (KAKENHI) 20H00193Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) Japan Society for the Promotion of Science 20J21145 PE17712 P18791New Zealand Ministry of Business, Innovation and Employment (MBIE) ANTA1801Ministry of Science and Innovation, Spain (MICINN)Spanish Government CTM2017-89711-C2-1-PEuropean Union through FEDER fund

    Groundwater Responses to Earth Tides: Evaluation of Analytical Solutions Using Numerical Simulation

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    Harmonic Earth tide components in well water levels have been used to estimate hydraulic and geomechanical subsurface properties. However, the robustness of various methods based on analytical solutions has not been established. First, we review the theory and examine the latest analytical solution used to relate well water levels to Earth tides. Second, we develop and verify a novel numerical model coupling hydraulics and geomechanics to Earth tide strains. Third, we assess subsurface conditions over depth for a range of realistic properties. Fourth, we simulate the well water level response to Earth tide strains within a 2D poroelastic layered aquifer system confined by a 100 m thick aquitard. We find that the non-linear inversion of analytical solutions to match two observations (amplitudes and phases) to multiple unknown parameters is sensible to the initial guess. We reveal that undrained, confined conditions are necessary for the analytical solution to be valid. This occurs for the dominant M2_2 frequency at depths >50 m and requires specific storage at constant strain of Sϵ ≥ 106^{−6} m1^{−1}, hydraulic conductivity of the aquitard of kl_l ≤ 5 ⋅ 105^{−5} ms1^{−1} and aquifer of ka_a ≥ 104^{−4} ms1^{−1}. We further illustrate that the analytical solution is valid in unconsolidated systems, whereas consolidated systems require additional consideration of the Biot modulus. Overall, a priori knowledge of the subsurface system supports interpretation of the groundwater response. Our results improve understanding of the effect of Earth tides on groundwater systems and its interpretation for subsurface properties

    RHEA v1.0: Enabling fully coupled simulations with hydro-geomechanical heterogeneity

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    Realistic modelling of tightly coupled hydro-geomechanical processes is relevant for the assessment of many hydrological and geotechnical applications. Such processes occur in geologic formations and are influenced by natural heterogeneity. Current numerical libraries offer capabilities and physics couplings that have proven to be valuable in many geotechnical fields like gas storage, rock fracturing and Earth resources extraction. However, implementation and verification of the full heterogeneity of subsurface properties using high-resolution field data in coupled simulations has not been done before. We develop, verify and document RHEA (Real HEterogeneity App), an open-source, fully coupled, finite-element application capable of including element-resolution hydro-geomechanical properties in coupled simulations. To extend current modelling capabilities of the Multiphysics Object-Oriented Simulation Environment (MOOSE), we added new code that handles spatially distributed data of all hydro-geomechanical properties. We further propose a simple yet powerful workflow to facilitate the incorporation of such data to MOOSE. We then verify RHEA with analytical solutions in one and two dimensions and propose a benchmark semi-analytical problem to verify heterogeneous systems with sharp gradients. Finally, we demonstrate RHEA\u27s capabilities with a comprehensive example including realistic properties. With this we demonstrate that RHEA is a verified open-source application able to include complex geology to perform scalable, fully coupled, hydro-geomechanical simulations. Our work is a valuable tool to assess challenging real-world hydro-geomechanical systems that may include different levels of complexity like heterogeneous geology and sharp gradients produced by contrasting subsurface properties

    Tipologías de consumidores de alcohol dentro de la práctica del botellón en tres ciudades españolas.

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    En este trabajo se entrevistó a 6.009 jóvenes que practican botellón (14-25 años) en tres ciudades de la Comunidad Valenciana, realizando un muestreo estratifi cado de centros de Secundaria, Bachiller,CF y Universidad. Se efectuó un análisis de conglomerados en dos fases con cada muestra con dos objetivos: identifi car tipologías de consumidores de alcohol en el botellón y realizar una validación cruzada de la solución obtenida. Las variables consideradas en los análisis fueron: sexo, grupo de edad (universitarios: U; estudiantes Secundaria: ES), realización o no de episodios intensivos de consumo, años practicando botellón y gramos de alcohol ingeridos. Los resultados muestran evidencia de validez de la estructura obtenida para los jóvenes que realizan episodios intensivos de consumo de alcohol, ya que aparece una estructura de cuatro grupos en las tres muestras (varones U, varones ES, mujeres U,mujeres ES), siendo siempre los varones quienes más consumen. Además, los ES consumen iguales cantidades de hol que los U, aunque llevan menos años consumiendo. Por su parte, entre los jóvenes que no realizan episodios intensivos de consumo de alcohol se observa cierta variabilidad en la estructura, siendo manifi esta la tendencia de las mujeres a igualar su consumo con el de los varones. Different typologies of alcohol consumers in the practice of «botellon» in three Spanish cities. In this work, 6,009 youngsters (14-25 years old) who practice the «botellon» were interviewed in three cities of the Valencian Community. After a stratifi ed sampling among college and noncollege students, a two-step cluster analysis was carried out for each sample with two aims: to identify different types of alcohol consumers in the practice of the «botellon» and to carry out a crossed validation of the results obtained. The variables included in the analysis were the following: gender, age group (university students: U; adolescent students: ES), performance of intensive episodes of consumption (yes/no), number of years practicing the «botellon» and grams of alcohol ingested. The results show the validity of the structure obtained for youngsters, revealing intensive episodes of alcohol consumption, as a fourgroup structure appeared in all three samples (male U, male ES, female U, female ES), in which men were always at the top of alcohol ingestion. Furthermore, ES consumed the same amount of alcohol as U, even though they had been consuming for less time. However, the youngsters who did not report intensive episodes of alcohol consumption showed some structure variability, with a tendency among women to match men"s levels of alcohol consumptio

    Representative elementary area for multifractal analysis of soil porosity using entropy dimension

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    International audienceThe notion of representative elementary area (REA) developed to address heterogeneity and scale problems in quantitative soil pedology comes from the notion of representative elementary volume of fluid dynamics in porous media. The REA allows the identification of the minimum area of a soil block section that is required to represent the pedofeature of interest based on its distribution in soil space. In this paper eight samples were imaged with two different techniques: the confocal microscope and the conventional film camera. These techniques provided information about pore sizes between 3.62 ?m and 161.98 ?m, and between 39.72 ?m and 1776.34 ?m, respectively. Sixteen of the resulting digital images were then analyzed to investigate the representative elementary area of the multifractal patterns of the spatial distribution of voids related to the micro and macroporosity by means of the entropy dimension. Our results permit the location of the REA region over the domain of the microstructures rendered by the analysis of the microscope images. They also suggest that this region seemingly spans scales of the macrostructures as revealed by the analysis of the camera pictures

    Estadística Descriptiva y Probabilidad: (Teoría y problemas)

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    XXXIV, 261 p. ; 24 cm.Libro ElectrónicoÍndice Bibliografía: p. [256]-258 Manual para alumnos de titulaciones experimentales que proporciona una visión práctica e intuitiva de la estadística descriptiva y el cálculo de probabilidades, campos básicos y fundamentales de la ciencia estadísticaLibro : Español (spa) : 3a. edIndice general Prólogo XIII 1. Introducción XIII 2. History (Histórico) XV 3. Licencia de Documentación Libre de GNU XVI 4. GNU Free Documentation License XXVI A Estadística Descriptiva 1 1 Síntesis de la información 7 1. Rese˜na histórica 7 2. La organización de la información 9 3. Representaciones grá?cas 15 4. Medidas centrales 17 5. Medidas de posición 26 6. Medidas de dispersión 27 7. Desigualdad de Tchebychev 31 8. Momentos de la distribución 31 9. Medidas de forma 33 10. Transformaciones 36 11. Análisis exploratorio de datos 37 12. Ejercicios 40 2 Análisis conjunto de variables. 53 1. Distribución conjunta de dos caracteres 53 2. Distribuciones marginales 55 3. Distribuciones condicionadas 55 4. Independencia 60 5. Medidas de dependencia. Coeficientes de relación 61 6. Ejercicios 78 3 Ajuste y regresión bidimensional 89 1. Introducción 89 2. Ajuste. Criterio de los mínimos cuadrados 91 3. Análisis de la bondad del ajuste 97 4. Regresión. Método de regresión a la media 100 5. Análisis de la bondad de la regresión 102 6. Notas y conclusiones 104 7. Ejercicios 105 B Probabilidad 113 4 Teoría de la probabilidad 117 1. Evolución histórica 117 2. Conjuntos. Operaciones 120 3. Algebra de sucesos 122 4. Distintas de?niciones del concepto de probabilidad 126 5. Propiedades de la función de probabilidad 129 6. Probabilidad condicionada. Independencia 131 7. Dependencia e independencia 132 8. Teorema de la probabilidad total. Teorema de Bayes 133 9. Ejercicios 136 5 Variable aleatoria 145 1. Concepto 145 2. Variables discretas y continuas 146 3. Variables unidimensionales 147 4. Variables multidimensionales 161 5. Ejercicios 173 6 Algunos modelos probabilísticos 185 1. Distribución uniforme discreta 185 2. Experimento de Bernouilli 186 3. Distribución hipergeométrica 191 4. Proceso de Poisson 192 5. Distribución uniforme continua 195 6. Distribución normal 197 7. Relación entre binomial, Poisson y normal 200 8. Teorema central del límite 201 9. Distribución gamma 202 10. Distribución beta 203 11. Distribución de Cauchy 204 12. Distribuciones derivadas de la normal 206 13. Distribución de Laplace 210 14. Distribución logística 211 15. Distribución de Pareto 211 16. Algunos modelos multidimensionales 212 17. Ejercicios 215 A Combinatoria 225 1. Introducción 225 2. Variaciones con repetición 225 3. Variaciones 226 4. Permutaciones 226 5. Permutaciones con repetición 226 6. Combinaciones sin repetición 227 7. Combinaciones con repetición 228 8. Ejercicios 228 B Tablas Estadísticas 233 C Bibliografía 25

    Filterbank Learning for Small-Footprint Keyword Spotting Robust to Noise

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    In the context of keyword spotting (KWS), the replacement of handcrafted speech features by learnable features has not yielded superior KWS performance. In this study, we demonstrate that filterbank learning outperforms handcrafted speech features for KWS whenever the number of filterbank channels is severely decreased. Reducing the number of channels might yield certain KWS performance drop, but also a substantial energy consumption reduction, which is key when deploying common always-on KWS on low-resource devices. Experimental results on a noisy version of the Google Speech Commands Dataset show that filterbank learning adapts to noise characteristics to provide a higher degree of robustness to noise, especially when dropout is integrated. Thus, switching from typically used 40-channel log-Mel features to 8-channel learned features leads to a relative KWS accuracy loss of only 3.5% while simultaneously achieving a 6.3x energy consumption reduction
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