Minimal set of generators of controllability space for singular linear dynamical systems

Due to the significant role played by singular systems in the form E ¿ x ( t ) = Ax ( t ) , on mathematical modeling of science and engineering problems; in the last years recent years its interest in the descriptive analysis of its structural and dynamic properties. However, much less effort has been devoted to studying the exact con- trollability by measuring the minimum set of controls needed to direct the entire system E ¿ x ( t ) = Ax ( t ) to any desired state. In this work, we focus the study on obtaining the set of all matrices B with a minimal number of columns, by making the singular system E ¿ x ( t ) = Ax ( t ) + Bu ( t ) controllable.Postprint (author's final draft

The prosody of central Mexican Spanish in the framework of the Project AMPER

La caracterización de los patrones prosódicos de las distintas variedades de una lengua es fundamental en el desarrollo de herramientas para el procesamiento de lenguaje natural, para el diagnóstico de alteraciones de la expresión, para la clasificación dialectológica y para el aprendizaje de L2, entre otras aplicaciones. Este estudio analiza los parámetros prosódicos (entonación, duración e intensidad) de la variedad del español hablada en el centro de México a partir de grabaciones de 756 oraciones enunciativas neutras e interrogativas absolutas pronunciadas por dos informantes locales. Se utilizaron las pautas metodológicas del proyecto AMPER para analizar los datos y la notación Sp-ToBI, en el marco del Modelo Métrico-Autosegmental, para describir las curvas halladas. Los resultados se contrastaron con los patrones de otras variedades del español habladas en España y en otras partes de Hispanoamérica mediante herramientas dialectométricas que permitieron cuantificar matemática y estadísticamente las distancias lingüísticas entre ellas.The characterization of the prosodic patterns of the different varieties of a language is fundamental in the development of natural language processing tools, the diagnosis of abnormal speech, dialectological classification, and second language learning, among other applications. This study analyzes the prosodic parameters (intonation, length, and loudness) of the variety of Spanish spoken in central Mexico through recordings of 756 broad-focus statements and information-seeking yes/no questions pronounced by two local informants. The data was analyzed following the methodological guidelines of the project AMPER and the Sp-ToBI notation system, within the Autosegmental-Metric Model framework, to describe the patterns. The results were contrasted with the patterns of other varieties of Spanish spoken in Spain and Latin America through dialectometric tools that allowed the mathematical and statistical quantification of the linguistic distances between them

Políticas de interrelación de la facultad de Bellas Artes de Barcelona y la empresa privada. Difusión de evidencias y competencias profesionales para nuestros estudiantes en una sociedad contemporánea

Políticas de interrelación de la facultad de Bellas Artes de Barcelona y la empresa privada. Difusión de evidencias y competencias profesionales para nuestros estudiantes en una sociedad contemporánea Resulta de extrema importancia el componente crítico y autocrítico en el discurso que desde las artes se pueda ir generando respecto a la sociedad que nos toca vivir. Es evidente que en la construcción de toda sociedad avanzada, el pensamiento y por tanto las artes, deben aportar un elemento de difusión de ideas que puedan aportar un valor añadido a la configuración de nuestras ciudades como aglutinantes de nuestra sociedad. Los medios de comunicación son herramientas clave para ese propósito. Es por tanto necesario conectar el arte con los medios y por ende al estudiante de arte con esos mecanismos de difusión, mediante publicaciones y exposiciones de esas ideas artísticas que recogen el verdadero pulso creativo de una sociedad emergente, representada por su juventud dentro de las universidades. En la búsqueda de nuevos mecanismos que dotasen a nuestra docencia de un componente de experiencia basada en la propia praxis de aquello concerniente a la puesta en escena de los resultados creativos, fruto de la producción artística de nuestros alumnos, nos movilizamos en el Departamento de Escultura de nuestra Facultad y particularmente desde la Comisión de Publicaciones y Exposiciones, para buscar empresas, revistas, editoriales, fundaciones, etc. al margen de los congresos relacionados con el tema, que nos permitieran poner en común dichos resultados, además de poder publicar artículos de los docentes que explicasen esas experiencias

Synthèse des impacts écologiques des feux et des coupes forestières sur les lacs de l'écozone boréale au Québec

Cet article présente une première synthèse comparative des impacts des feux et des coupes forestières sur la qualité des eaux et les communautés aquatiques des lacs de l'écozone boréale de l'est du Canada. La recherche a été réalisée de 1996 à 1998 dans le cadre d'un projet du Réseau de centre d'excellence sur la gestion durable des forêts (RCE-GDF) et porte sur 38 lacs du Bouclier Canadien du Québec. Les changements dans la qualité de l'eau ainsi que dans la diversité, la biomasse et la structure des communautés de plancton et de poissons ont été suivis pendant trois ans dans 20 lacs dont les bassins versants étaient non perturbés, dans 9 lacs qui avaient subit des coupes forestières et dans 9 lacs qui avaient subit des feux de forêt.Notre étude montre que les feux et les coupes ont des impacts significatifs qui diffèrent selon le type de perturbation. En général, les lacs affectés par les coupes et les feux ont des concentrations de phosphore 2 à 3 fois plus élevées que les lacs de référence. Toutefois, les lacs affectés par les feux montrent des concentrations en nitrates beaucoup plus élevées tandis que les lacs affectés par les coupes sont moins transparents et ont des eaux plus colorées, très riches en carbone organique dissous. Les feux et les coupes affectent aussi de façon différente la minéralisation des eaux et les concentrations des ions majeurs. Les feux et les coupes n'ont pas d'effet sur la biodiversité des communautés planctoniques, sauf dans les lacs ayant un grand bassin versant et plus de 40 % de perturbation. Aucune différence n'a été observée entre les lacs de référence et les lacs perturbés au niveau de l'occurrence, l'abondance et la croissance des espèces de poissons. En revanche, les feux et les coupes affectent la production et la structure des communautés aquatiques. Dans les lacs affectés par les feux, l'enrichissement en azote et phosphore provoque une hausse de la concentration en chlorophylle a, et de la biomasse du phytoplancton et du limnoplancton (seston > 53 µm), en particulier des diatomées, des rotifères et des gros crustacés, pendant deux à trois années après les feux. En revanche, dans les lacs affectés par les coupes, l'enrichissement en phosphore n'entraîne qu'une augmentation très faible et limitée à un an de la biomasse des algues et pas de changement dans les biomasses du limnoplancton, en raison de la forte couleur et de la transparence réduite des eaux, qui limite la production biologique. Les coupes ont un impact négatif sur les copépodes calanoïdes, un groupe de zooplancton caractéristique des lacs oligotrophes et transparents. Une diminution significative de la proportion des individus de petite taille a été observée chez les populations de perchaude et de meunier noir des lacs perturbés (lacs de coupe et de feux formant un seul groupe). Les impacts observés dans la qualité des eaux et la production du plancton augmentent avec l'importance relative des perturbations au niveau du bassin versant. Cependant, la variabilité dans les caractéristiques des bassins versants et des lacs, en particulier le rapport de drainage et le temps de résidence des eaux, a des effets confondants sur les réponses des écosystèmes lacustres aux perturbations par les feux et les coupes.This paper presents a comparative review on ecological impacts of wildfires and harvesting on water quality and aquatic community attributes of boreal lakes in eastern Canada. This project was carried out from 1996 to 1998, as part of the research program of the Sustainable Forest Management Network Centre of Excellence (NCE-SFM), on 38 lakes of the Boreal Canadian Shield (Québec, Canada). Changes in water quality, and in diversity, biomass and community structure of pelagic plankton and fish populations were monitored for 3 years in 20 reference lakes, 9 cut lakes and 9 burnt lakes.Our study shows that wildfires and logging have significant impacts on water quality as well as primary and secondary producers in boreal lakes. However, fire and logging does not have similar impacts. In general, cut and burnt lakes showed higher concentrations of total phosphorus (TP: 2-3 folds) than reference lakes. However nitrates concentrations (NO3-) were higher in burnt lakes than in reference and cut lakes, whereas dissolved organic carbon (DOC), light extinction coefficient (e PAR) and water colour were higher in cut lakes than in reference lakes, burnt lakes showing intermediate values. Wildfire and logging also affect ionic composition of lake water. Both burnt and cut lakes had higher concentrations of potassium (K+), chloride (Cl-) and calcium (Ca2+) than reference lakes, while sulphates (SO42-) and magnesium (Mg2+) increased only in burnt lakes. The observed increases in organic and mineral elements reflect their export from the watershed and were related to the drainage ratio. As mobile ions are rapidly flushed from the perturbed watersheds, ionic water composition returned to normal levels within three years after the perturbation. In contrast, some changes in water quality (P and N enrichment in perturbed lakes; DOC increase in cut lakes) seems to be on longer term and might have a more important effect on limnological features of lakes such as thermal stratification, mixed and euphotic depth, plankton biomass and bioaccumulation of mercury in zooplankton and fish.Wildfires and logging do not have significant impacts on species richness of planktonic communities, except for lakes with large drainage basins and those where the perturbation was higher than 40% of the watershed area. However, wildfires and logging affect biomass of plankton communities. In burnt lakes, the nutrient enrichment induced important increases in Chl. a concentration and phytoplankton biomass, and a small increase in limnoplankton biomass (seston > 53 µm). Diatoms, rotifers and large crustaceans showed significant increases. In burnt lakes, increases in phytoplankton were observed during the three years of the survey and were highest in the first 2 years after fires. Limnoplankton increases lasted only 2 years and were highest the second year after fires. In cut lakes, nutrient enrichment was not reflected in a proportional increase in plankton production due to increase in DOC concentrations and lake water colour that reduced water transparency. Phytoplankton slightly increased only the first year after logging and no increase was observed for limnoplankton and zooplankton. Logging negatively affect calanoids, a zooplankton group characteristic of clear and oligotrophic lakes. No significant differences were observed in the occurrence, abundance and growth of fish populations among reference and perturbed lakes. However, the proportion of small yellow perch and white sucker were significantly lower in populations of impacted lakes (burned and logged lakes pooled). In most cases, impacts on water quality and plankton communities were related to the intensity of fire or logging, when expressed as the percent area of watershed harvested or burnt divided by the lake surface or volume. Simple models may then be developed and help to predict the effect of harvesting practices on lake ecosystems. However, environmental variation in watershed and lakes characteristics, especially drainage ratio and lake water residence time, are important confounding factors in the responses of lakes to watershed perturbations by fire or logging. Lakes with drainage ratio > 4 and with more of 30% of their watershed perturbed are the most sensitive to fire and logging. These factors should be considered when developing lake management models in the boreal forest impacted by fire and logging

Beta-blockers to prevent gastroesophageal varices in patients with cirrhosis.

BACKGROUND: Nonselective beta-adrenergic blockers decrease portal pressure and prevent variceal hemorrhage. Their effectiveness in preventing varices is unknown. METHODS: We randomly assigned 213 patients with cirrhosis and portal hypertension (minimal hepatic venous pressure gradient [HVPG] of 6 mm Hg) to receive timolol, a nonselective beta-blocker (108 patients), or placebo (105 patients). The primary end point was the development of gastroesophageal varices or variceal hemorrhage. Endoscopy and HVPG measurements were repeated yearly. RESULTS: During a median follow-up of 54.9 months, the rate of the primary end point did not differ significantly between the timolol group and the placebo group (39 percent and 40 percent, respectively; P=0.89), nor were there significant differences in the rates of ascites, encephalopathy, liver transplantation, or death. Serious adverse events were more common among patients in the timolol group than among those in the placebo group (18 percent vs. 6 percent, P=0.006). Varices developed less frequently among patients with a baseline HVPG of less than 10 mm Hg and among those in whom the HVPG decreased by more than 10 percent at one year and more frequently among those in whom the HVPG increased by more than 10 percent at one year. CONCLUSIONS: Nonselective beta-blockers are ineffective in preventing varices in unselected patients with cirrhosis and portal hypertension and are associated with an increased number of adverse events. (ClinicalTrials.gov number, NCT00006398.

A process centred virtual approach to support cost estimating along product life cycle

The application of engineering practices and scientific principles to the creation of cost estimates along a product life cycle is one of the basic aspects of Cost Engineering. Cost estimates are used as fundamental criteria to make design decisions in the development stage and also to make business decisions in collaboration between OEMs and their supply chain. The achievement of an estimate requires experience and knowledge of different techniques and methodologies. Key aspects on its creation are the adoption of a cost estimating process, the availability of the needed data and the proper management of the information used during the process. The collaboration between the OEM and its supplier can be facilitated by having a better common understanding of how the cost estimates have been created. The cost estimating process used is then a fundamental piece of trust. In this context, the main purpose of this paper is to present the research conducted in the definition of cost estimating processes and the virtual framework selected. They are the key elements in the development of a prototype set of virtual tools to support the creation of cost estimates, the improvement of competences of the Cost Engineering Community, and the common understanding on cost between OEMs and their supply chain

Multidisciplinary consensus on the approach to hospital malnutrition in Spain

Rationale: Disease-related malnutrition constitutes a highly prevalent healthcare problem with high costs associated. In Spain, the prevalence of malnutrition in hospitalized patients has been reported from 30% to 50%. Objectives: Main purposes of this consensus document were to establish recommendations that facilitate decision- making and action to prevent and early-diagnose disease-related hospital malnutrition, on the management of nutritional support methods and actions to evaluate nutritional treatment compliance and efficacy. Methods: A systematic bibliographical search of authors was performed, complemented by updated bibliography by author references up to 2010. From this review, some recommendations were defined, modified and critically evaluated by the representatives of scientific societies in a consensus conference (Dec 2010) following a structured brainstorming technique: the Metaplan® technique. A double validation process was undertaken until final recommendations were obtained. Results: 30 consensus recommendations for the prevention and management of hospital malnutrition are presented in this document. Recommendations cover all clinical care settings as well as prevention, screening, diagnosis, treatment and follow-up of disease-related malnutrition. Conclusions: Nutritional screening is strongly recommended at all clinical settings when nutritional risk factors are identified or there is clinical suspicion of malnutrition. Nutritional assessment should be designed and performed according to centers’ resources, but clearly identified protocols should be available.La desnutrición relacionada con la enfermedad constituye un problema sanitario de elevada prevalencia y altos costes. En España, la prevalencia de desnutrición de los pacientes hospitalizados se ha estimado entre el 30% y el 50%. Objetivos: El objetivo principal de este consenso fue establecer recomendaciones para facilitar la toma de decisiones para la prevención y el diagnostico precoz de la desnutrición hospitalaria, el manejo del soporte nutricional, y las acciones para evaluar el cumplimiento de la intervención nutricional y su eficacia. Métodos: Se realizó una búsqueda sistemática de autor complementada por bibliografía actualizada por referencias de autor hasta el año 2010. A partir de esta revisión, se definieron algunas recomendaciones que fueron criticadas y modificadas por los representantes de las Sociedades Científicas participantes en una conferencia de consenso (Diciembre 2010) siguiendo una técnica de brainstorming estructurado: la técnica Metaplan®. Se realizaron dos vueltas de validación de las recomendaciones hasta obtener las recomendaciones finales. Resultados: Este documento presenta 30 recomendaciones para la prevención y el manejo de la desnutrición hospitalaria. Las mismas cubren todas las áreas de actuación clínica así como la prevención, cribado, diagnóstico, tratamiento y seguimiento de la desnutrición hospitalaria relacionada con la enfermedad. Conclusiones: Se recomienda enérgicamente el cribado nutricional en todas las áreas de actuación clínica cuando se identifiquen factores de riesgo nutricional o sospecha clínica de desnutrición. La valoración del estado nutricional debe diseñarse y realizarse de acuerdo a los recursos disponibles en cada centro, disponiendo de claros protocolos de actuación

GEOMETRICAL CHARACTERIZATION OF LIQUID CORE FIBERS BY MEASUREMENT OF THERMALLY INDUCED MODE CUTOFFS AND INTERFERENCE

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