2,405 research outputs found

    MIMO PID Controller Tuning Method for Quadrotor Based on LQR/LQG Theory

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    In this work, a new pre-tuning multivariable PID (Proportional Integral Derivative) controllers method for quadrotors is put forward. A procedure based on LQR/LQG (Linear Quadratic Regulator/Gaussian) theory is proposed for attitude and altitude control, which suposes a considerable simplification of the design problem due to only one pretuning parameter being used. With the aim to analyze the performance and robustness of the proposed method, a non-linear mathematical model of the DJI-F450 quadrotor is employed, where rotors dynamics, together with sensors drift/bias properties and noise characteristics of low-cost commercial sensors typically used in this type of applications are considered. In order to estimate the state vector and compensate bias/drift effects in the measures, a combination of filtering and data fusion algorithms (Kalman filter and Madgwick algorithm for attitude estimation) are proposed and implemented. Performance and robustness analysis of the control system is carried out by employing numerical simulations, which take into account the presence of uncertainty in the plant model and external disturbances. The obtained results show the proposed controller design method for multivariable PID controller is robust with respect to: (a) parametric uncertainty in the plant model, (b) disturbances acting at the plant input, (c) sensors measurement and estimation errors

    ACUTA eNews June 2014 Vol. 43, No. 6

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    In this Issue... The Association for College and University Technology Advancement What\u27s on Your Desk? Register for Fall Seminar in Boston ACUTA\u27s Summer Webinars The Telephony IP Transition: Circumventing FCC Oversight Stream Annual Conference 2014 Annual Dues Invoices Mailed Info Links The Real Impact of Leadership Check lt Ou

    INFLUENCIA DE SACCHAROMYCES CEREVISIAE EN LA EFICIENCIA AMBIENTAL DE LA PRODUCCIÓN DE METANO EN GANADO LECHERO Y GANADO DE ENGORDA”: META-ANÁLISIS

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    The use of feed additives (e.g. yeasts products) for reduction of ruminants’ methane (CH4) production has drawn the attention of cattle nutritionists and environmentalists. Although there are many relevant studies on this topic, but the obtained results for dairy and beef cattle are contradictory. Therefore, the objective of the present study is to examine the effect of yeast (Saccharomyces cerevisiae) on reduction of CH4 production in dairy and beef cattle using meta-analytic methods. After compilation of relevant articles published between 1990 and 2016 and applying exclusion and inclusion criteria, meta-analyses of data from dairy and beef cattle were applied for the pooled dataset or for each animal category (dairy or beef). The effect size of yeast on CH4 production (g/day) and CH4 production per dry matter intake (CH4/DMI (g/kg)) was estimated as standardized mean difference at 95% confidence interval. In addition, heterogeneity across studies was tested by using Q test and I2 index. Study bias was verified through Funnel plot and trim-and-fill method. The results of meta-analysis of all 3 groups of animals (all cattle, dairy cattle, and beef cattle) suggested that effect size of yeast on CH4 production (g/day) and CH4/DMI (g/kg) was not significant. In other words, the use of yeast for dairy and beef cattle did not reduce CH4 production and CH4/DMI (g/kg) significantly. The results of Q test and I2 index suggest that there is no heterogeneity between different studies on CH4 production and CH4/DMI (g/kg) so that value of I2 index of CH4/DMI (g/kg) in dairy and beef cattle was about 14% while for dairy cattle, the index is about 40%. There was no study bias of CH4 production as well as CH4/DMI (g/kg). As shown in funnel plot, the studies are more concentrated in the lowest part of the plot. The results of meta-analysis suggest that use of yeast (Saccharomyces cerevisiae) as feed additive does not offer significant results in terms of reduction of CH4 production in dairy and beef cattle. It is recommended to conduct further studies on effect of different doses of yeast, use of yeast products, different strains and experimental designs

    In vivo strategies for the study of ubiquitination and ubiquitin-related diseases: application to Angelman syndrome

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    287 p.Ubikuitilazioa neuronen garapenerako eta funtzionamendurako ezinbesteko da. Neuronetan ubikuitina itsatsita daukaten proteinen identifikazioak asko lagunduko luke prozesu honek garunean dituen zereginak hobeto ulertzeko. Baina ubikuitinatuak dauden proteinak kopuru oso txikian aurkitu ohi direnez, haien identifikazioa lan zaila da.Ugo Mayor Doktorearen laborategiak ubikuitinak kontrolatzen dituen proteinak ikertzeko estrategia eraginkor bat garatu du. Hain zuzen ere, estrategia ubikuitina biotinarekin in vivo markatzean datza. Tesi honetan zehar, estrategia hori Drosophilaren foto-errezeptoreetara hedatu dugu, ubikuitinazio bidezidorrak neurona heldu baten markoan ikertzeko in vivo eredu bat hedatuz. Bestalde, metodologia horren bidez Drosophila Ube3aren lehendabiziko in vivo substratua aurkitu dugu. E3 ligasa hori gizakietan Angelman sindromearen arduraduna da. Gainera, GFP-erauzketa metodo bat garatu dugu proteina bakarra isolatu eta bere ubikuitinatutako frakzioaren ikerkuntza errazten duena. Protokolo horretaz baliatuz, Ube3aren beste lau substratu biokimikoki balioztatu ditugu neurona-antzeko zelula sistema batean. Tesi honetan garatutako bi metodologiak ubikuitinazioa ikertzeko dauden beste estrategiak osatzeko abantaila apartak eskaintzen dituzte. Protokolo bi hauek ubikuitinazioan arazoak dituzten gaixotasunak hobeto ulertzen lagunduko dute etorkizunean

    Role of shared information systems in distribution channels

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    Some manufacturers are reluctant to rationally share their Information Systems (ISs) with their dealers. Through a detailed case study analysis, we explore what could impel a manufacturer to overcome its reluctance by analysing its control problems (lack of direction; motivational; and personal limitations). We show that sharing ISs provides benefits derived from the collection of information in both quantity and quality that is in turn utilized by the manufacturer. It ensures that the manufacturer controls operations with proper information, seeing the market through dealers. Therefore, manufacturers could share ISs in order to proactively manage their distribution channels in a non-coercive way.Algunos productores son reacios a compartir de forma racional sus sistemas informáticos (ISs en inglés) con sus comerciantes. Mediante un análisis detallado de un caso práctico, hemos explorado qué podría impulsar a un productor a superar su reticencia, al analizar su problemas de control (falta de dirección; limitaciones motivacionales; y personales). Se muestra que compartir los ISs aporta beneficios que derivan de la colección de información, tanto en cantidad como en calidad, lo que se utiliza en cambio por el productor. Esto asegura que el productor controla las operaciones con información apropiada, viendo de esa manera el mercado a través de los comerciantes. Por ello, los productores podrían compartir los ISs para dirigir proactivamente sus canales de distribución en una manera no coercitiva

    Producción e impacto de las instituciones españolas de investigación en Arts and Humanities Citation Index (2003-2012)

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    This essay reviews both the scholarly output and impact factor of Spanish research institutions in the Arts & Humanities Citation Index (A&HCI) database, managed by the Thomson-Reuters Web of Science. Based on a bibliometric analysis of a range of variables it has been possible to identify those institutions with the best performance indicators, the journals publishing the most articles, the most productive areas of research, and other relevant data on publishing patterns in the Humanities. The study reveals that the most productive Spanish institutions in the Humanities are the same as those that lead the performance figures in other areas; it also highlights the outstanding production of the Spanish National Research Council (CSIC)

    Asymmetric Pattern of Correlations of Leucine Aminopeptidase Activity between Left or Right Frontal Cortex versus Diverse Left or Right Regions of Rat Brains

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    Previous studies demonstrated an asymmetry of left predominance for mean values of soluble leucine aminopeptidase (LeuAP) activity in the frontal cortex (FC) and hypothalamus of adult male rats, fluorimetrically analyzed by the hydrolysis of Leu- -naphthylamide as a substrate. No asymmetries were observed in nine other left (L) and right (R) regions obtained from rostrocaudally sectioned coronal slices. Neither had inter-hemispheric differences observed for lactate dehydrogenase (LDH), analyzed simultaneously in the same brain regions (L and R) of the same animals. However, the level of intra-hemispheric or inter-hemispheric correlation of LeuAP or LDH between such brain regions has not been analyzed. In order to obtain additional suggestions on the functional heterogeneity between regions of LeuAP and LDH, in the present investigation, the level of intra-hemispheric and inter-hemispheric correlations of the frontal cortex with the rest of the regions studied is described: (A) between the left frontal cortex (LFC) and the rest of the left regions; (B) between the right frontal cortex (RFC) and the rest of the right regions; (C) between the left frontal cortex and all of the right regions; and (D) between the right frontal cortex and all of the left regions. All of the correlations obtained were positive. The intra-hemispheric analysis showed a greater heterogeneity of values in the correlations observed between RFC and the rest of the right regions than between LFC and the rest of the left regions. Greater heterogeneity is observed when comparing RFC correlations with left regions than when comparing LFC correlations with right regions. In conclusion, the greatest heterogeneity (suggesting a greater functional variability) was observed in the right intra-hemispheric analysis and in the inter-hemispheric analysis between the RFC and the left hemisphere. The results for LDH showed a great homogeneity between regions both in the intra- and inter-hemispheric studies.University of Jaén “Neuroendocrinology and Nutrition” BIO-22

    Brain Asymmetry: Towards an Asymmetrical Neurovisceral Integration

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    This review was supported by the group of the University of Jaen "Neuroendocrinology and Nutrition" BIO-221.Despite the ancestral evidence of an asymmetry in motor predominance, going through the inspiring discoveries of Broca and Wernicke on the localization of language processing, continuing with the subsequent noise coinciding with the study of brain function in commissurotomized patients—and the subsequent avalanche of data on the asymmetric distribution of multiple types of neurotransmitters in physiological and pathological conditions—even today, the functional significance of brain asymmetry is still unknown. Currently, multiple evidence suggests that functional asymmetries must have a neurochemical substrate and that brain asymmetry is not a static concept but rather a dynamic one, with intra- and inter-hemispheric interactions between its various processes, and that it is modifiable depending on changing endogenous and environmental conditions. Furthermore, based on the concept of neurovisceral integration in the overall functioning of an organism, some evidence has emerged suggesting that this integration could be organized asymmetrically, using the autonomic nervous system as a bidirectional communication pathway, whose performance would also be asymmetric. However, the functional significance of this distribution, as well as the evolutionary advantage of an asymmetric nervous organization, is still unknown.University of Jaen "Neuroendocrinology and Nutrition" BIO-22

    Paisajes epigráficos en la "provincia Hispania citerior" en época de Augusto

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    Se estudia la diversidad de contextos de exhibición de las inscripciones romanas en la provincia Hispania citerior en época augustea, atendiendo a la importancia que adquirieron las ciudades en el proceso de romanización del territorio, así como a la configuración de nuevos espacios de exposición de las inscripciones, en algunos casos dentro de las estrategias de promoción y autorrepresentación de las elites locales

    La cooperativa: un modelo alternativo en la producción de vivienda social

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    Esta investigación aborda el problema del déficit de vivienda en México y las maneras cómo el Estado, la iniciativa privada y la sociedad civil han encarado esta situación. Hace énfasis en el análisis de las cooperativas de vivienda como una alternativa real fundamentada en bases jurídicas y experiencias concretas que le permiten ser una opción a esta necesidad social. Plantea formas de clasificación de las cooperativas de vivienda y describe y analiza los procesos de vivienda cooperativa más significativos desde 1970 hasta principios de la década del 2000 tanto en el país como en el estado de Jalisco. Hace una comparación en las experiencias existentes en esta entidad federativa entre la cooperativa de vivienda, las asociaciones civiles, los asentamientos irregulares y los programas institucionales de vivienda. Analiza el desempeño, los retos, los logros y el papel de esta figura asociativa dedicada al impulso de la construcción de vivienda desde la sociedad civil jalisciense.ITESO, A.C
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