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Search Results: 1 - 10 of 213376 matches for " Juan David; Aguilar V. "
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Un análisis de la dinámica de largo plazo de la UVR
Velásquez H.,Juan David; Aguilar V.,Soraida;
Revista Ingenierías Universidad de Medellín , 2011,
Abstract: box and jenkins models have been used for modeling and forecasting of many economic and financial variables. in this article, that methodology was used as an alternative to analyze the long- term dynamics of the constant value unit. the final model was accepted after applying several standard tests of diagnostic. the sarima model was accepted after having used an amount of standard diagnostic tests, as result of it, the model fit well to the data, and explorative prediction accuracy is acquired when it represents the cycle patterns and for long term.
Un análisis de la dinámica de largo plazo de la UVR Analysis of the long term dynamics of the constant value unit
Juan David Velásquez H.,Soraida Aguilar V.
Revista Ingenierías Universidad de Medellín , 2011,
Abstract: Los modelos de Box y Jenkins han sido ampliamente usados para la modelación y el pronóstico de muchas variables económicas y financieras. En este artículo se explora la utilización de dicha metodología como una alternativa para el análisis de la dinámica de largo plazo del UVR. El modelo SARIMA resultante fue aceptado después de aplicarle una serie de pruebas estándar de diagnóstico; lo cual dio como resultado que el modelo se ajusta de manera adecuada a los datos, y que la precisión del pronóstico extrapolativo se ajusta estadísticamente bien al representar los patrones ciclos y de largo plazo. Box and Jenkins models have been used for modeling and forecasting of many economic and financial variables. In this article, that methodology was used as an alternative to analyze the long- term dynamics of the constant value unit. The final model was accepted after applying several standard tests of diagnostic. The SARIMA model was accepted after having used an amount of standard diagnostic tests, as result of it, the model fit well to the data, and explorative prediction accuracy is acquired when it represents the cycle patterns and for long term.
An Overview of Kinematic and Calibration Models Using Internal/External Sensors or Constraints to Improve the Behavior of Spatial Parallel Mechanisms
Ana C. Majarena,Jorge Santolaria,David Samper,Juan J. Aguilar
Sensors , 2010, DOI: 10.3390/s101110256
Abstract: This paper presents an overview of the literature on kinematic and calibration models of parallel mechanisms, the influence of sensors in the mechanism accuracy and parallel mechanisms used as sensors. The most relevant classifications to obtain and solve kinematic models and to identify geometric and non-geometric parameters in the calibration of parallel robots are discussed, examining the advantages and disadvantages of each method, presenting new trends and identifying unsolved problems. This overview tries to answer and show the solutions developed by the most up-to-date research to some of the most frequent questions that appear in the modelling of a parallel mechanism, such as how to measure, the number of sensors and necessary configurations, the type and influence of errors or the number of necessary parameters.
Good Living as an Alternative to the Young Entrepreneurship. An Evaluation from Social Relationship and Productions Perspective  [PDF]
Tannia Cristina Poveda Morales, José Fabián Fonseca Vásconez, Reynol Hernández Maden, Juan Bladimir Aguilar Poaquiza
Open Journal of Social Sciences (JSS) , 2016, DOI: 10.4236/jss.2016.49009
Abstract: The need to promote the review, the structure and restructuring of scientific alternatives and economic models for creating companies claiming the preservation of the planet and create better living conditions for humanity can be considered as possible solutions to the overexploitation of the planet and the inequitable distribution of wealth, which has led to economic and social crisis, present in vulnerable populations, youth unemployment and the lack of jobs do not guarantee a lifestyle based on dignity and development. This study focuses on theoretical methods, historicallogical analysis, inductive-deductive analysis, and chart analysis to understand relevant facts and phenomena during the investigation of young entrepreneurs in the case study. The scope of this study lies in identifying the elements involved in the intention to undertake the influential features in this process, which is a contribution to future entrepreneurs.
Modelling and Calibration Technique of Laser Triangulation Sensors for Integration in Robot Arms and Articulated Arm Coordinate Measuring Machines
Jorge Santolaria,David Guillomía,Carlos Cajal,José A. Albajez,Juan J. Aguilar
Sensors , 2009, DOI: 10.3390/s90907374
Abstract: A technique for intrinsic and extrinsic calibration of a laser triangulation sensor (LTS) integrated in an articulated arm coordinate measuring machine (AACMM) is presented in this paper. After applying a novel approach to the AACMM kinematic parameter identification problem, by means of a single calibration gauge object, a one-step calibration method to obtain both intrinsic―laser plane, CCD sensor and camera geometry―and extrinsic parameters related to the AACMM main frame has been developed. This allows the integration of LTS and AACMM mathematical models without the need of additional optimization methods after the prior sensor calibration, usually done in a coordinate measuring machine (CMM) before the assembly of the sensor in the arm. The experimental tests results for accuracy and repeatability show the suitable performance of this technique, resulting in a reliable, quick and friendly calibration method for the AACMM final user. The presented method is also valid for sensor integration in robot arms and CMMs.
3D Geometrical Inspection of Complex Geometry Parts Using a Novel Laser Triangulation Sensor and a Robot
Francisco Javier Brosed,Juan José Aguilar,David Guillomía,Jorge Santolaria
Sensors , 2011, DOI: 10.3390/s110100090
Abstract: This article discusses different non contact 3D measuring strategies and presents a model for measuring complex geometry parts, manipulated through a robot arm, using a novel vision system consisting of a laser triangulation sensor and a motorized linear stage. First, the geometric model incorporating an automatic simple module for long term stability improvement will be outlined in the article. The new method used in the automatic module allows the sensor set up, including the motorized linear stage, for the scanning avoiding external measurement devices. In the measurement model the robot is just a positioning of parts with high repeatability. Its position and orientation data are not used for the measurement and therefore it is not directly “coupled” as an active component in the model. The function of the robot is to present the various surfaces of the workpiece along the measurement range of the vision system, which is responsible for the measurement. Thus, the whole system is not affected by the robot own errors following a trajectory, except those due to the lack of static repeatability. For the indirect link between the vision system and the robot, the original model developed needs only one first piece measuring as a “zero” or master piece, known by its accurate measurement using, for example, a Coordinate Measurement Machine. The strategy proposed presents a different approach to traditional laser triangulation systems on board the robot in order to improve the measurement accuracy, and several important cues for self-recalibration are explored using only a master piece. Experimental results are also presented to demonstrate the technique and the final 3D measurement accuracy.
Efectos del entrenamiento físico en piscina climatizada sobre la capacidad aeróbica de un grupo de ni os asmáticos. (Effects of the physical training in a warm-water pool on the aerobic power of a group of asthmatic children.)
Juan David Fernández Villada,Elkin Eduardo Roldán Aguilar,María Helena Lopera Zapata
RICYDE : Revista Internacional de Ciencias del Deporte , 2009,
Abstract: Resumen Objetivo: Observar cambios en la capacidad aeróbica de un grupo de ni os asmáticos después de un entrenamiento físico en piscina climatizada (EFPC). Método: 22 ni os asmáticos, se dividieron en grupo experimental (GE) y grupo control (GC) de 11 cada uno. El GE se sometió a un EFPC durante 18 semanas de manera controlada, mientras el GC solo hacía sus actividades cotidianas. A ambos grupos se les realizó pruebas de esfuerzo en banda rodante para determinar el máximo consumo de oxígeno en METS y la frecuencia cardiaca máxima (FCM). Se midió en cada sesión de EFPC si los ni os presentaban asma inducida por esfuerzo (AIE). Resultados: Al iniciar el estudio, el promedio de METS y de la FCM fueron similares en ambos grupos (Anova METS p = 0.5568; Anova FCM p = 0.5198; METS: GE 11.61 ± 2.33 DS, GC 11.05 ± 2.08 DS; FCM: GE 165.09 ± 13.85 DS, GC 161.46 ± 12.12 DS). Al finalizar, sólo el GE mejoró en los promedios de los METS de la diferencia pre-post según la prueba de observaciones apareadas (METS GE 6.65 ± 3.46 DS; Anova p = 0.0006). La FCM también aumentó, siendo significativa en el GE (FCM: GE 22.45 ± 19.04 DS; Anova FCM p = 0.0823). Solo el 6,06% de las mediciones presentaron AIE. Conclusión: Se encontró aumento significativo de la capacidad aeróbica en el GE, comparado con el GC. Se sugiere que utilizar piscina climatizada para el entrenamiento físico del asmático puede disminuir el AIE.Abstract Objective: To observe changes in the aerobic power in a group of asthmatic children after of a physical training in warm-water pool (EFPC). Method: 22 asthmatic children, who were divided in to an experimental group (GE) and a control group (GC) of 11 each. The GE was submitted to an EFPC for 18 weeks in a controlled way, while the GC only did their daily activities. Treadmill ergometer testing were conducted to both groups, to determine the maximal oxygen consumption in MET and the maximum heart rate (FCM). Each section of the EFPC was measure to check if Children?children presented exercise-induced asthma (AIE). Results: At the beginning of the study, the average of METs and of the FCM were similar in both groups (Anova METs p = 0.5568; Anova FCM p = 0.5198; METs: GE 11.61 ± 2.33 DS, GC 11.05 ± 2.08 DS; FCM: GE 165.09 ± 13.85 DS, GC 161.46 ± 12.12 DS). At the end, only the GE improved in the averages of the difference between the pre-post test, both in the METs and in the FCM, according to the tests of paired observations (METs GE 6.65 ± 3.46 DS; Anova p = 0.0006). The FCM also increased, but acceptably in the GE (FCM: GE 22.45 ± 19.04 DS; Anova FCM p = 0
Una visión global del e.Learning y su e.Market
Vázquez,Guillermo; Lago,Juan; Riley,David;
Educación Médica , 2006, DOI: 10.4321/S1575-18132006000700012
Abstract: las tecnologías de la información y de la comunicación y su aplicación en la formación y entrenamiento de los profesionales, mediante el elearning, supone una de las grandes revoluciones que caracterizan a la sociedad del conocimiento. sin embargo solo una estrategia global que encare todas sus facetas simultáneamente puede acompasar el desarrollo tecnológico y su implementación efectiva. en este artículo los autores subrayan en primer lugar la importancia del liderazgo en la fase actual de implantación y aceptación del elearning, y los punto claves sobre los que se debe de sustentar. en segundo lugar explican las características de las acciones formativas online, y su engarce en un campus virtual. en tercer lugar se explican las características tecnológicas del elearning. finalmente recalcan la necesidad de un emarket para asegurar que lo altos costes de una nueva metodología, son sostenibles.
Aproximación crítica a los trastornos somatomorfos en ni os Critical Approach to Somatomorphic Disorders in Children
Juan David Ramos Guevara,Rafael Vásquez
Revista Colombiana de Psiquiatría , 2012,
Abstract: Los trastornos somatomorfos tienen en común manifestaciones somáticas que no tienen explicación médica y que pueden producir una alteración de la vida diaria. En ni os, existen dificultades de evaluación por el reporte u observación de síntomas debido a su edad, a la influencia parental y a los factores asociados. El objetivo de este trabajo es reconocer las dificultades diagnósticas y las herramientas clínicas que permitan la aproximación a los trastornos somatomorfos en ni os. Se realizó una búsqueda sistemática de la información publicada en los últimos diez a os sobre el tema. La evolución histórica del concepto de somatización ha generado dificultades en su abordaje. Algunas signos pueden hacer sospechar un trastorno somatomorfo; sin embargo, existen muy pocas herramientas de evaluación en ni os. Actualmente, dichas herramientas se basan solamente en listas de síntomas y no responden por completo a todos los interrogantes. Los trastornos somatomorfos o síntomas somáticos en ni os son un campo con un vacío aún por llenar. Somatomorphic disorders have common somatic manifestations without medical explanation, that can affect daily life. There are evaluation difficulties regarding symptom report or observation in children due to their age, parental influence and associated factors. The aim of this work is to acknowledge diagnosis difficulties and clinic tools to approach somatomorphic disorders in children. A systematic search in the information published for the last ten years was carried out. Historical evolution of the concept of somatization has generated difficulties to approach this issue. Some signs could indicate a somatomorphic disorder; however, there are very little evaluating tools for children. Currently, said tools are only based on lists of symptoms without fully answering to all questions. Somatomorphic disorders or somatic symptoms in children are still a gap to be closed.
Una visión global del e.Learning y su e.Market
Guillermo Vázquez,Juan Lago,David Riley
Educación Médica , 2006,
Abstract: Las Tecnologías de la Información y de la Comunicación y su aplicación en la formación y entrenamiento de los profesionales, mediante el eLearning, supone una de las grandes revoluciones que caracterizan a la Sociedad del Conocimiento. Sin embargo solo una estrategia global que encare todas sus facetas simultáneamente puede acompasar el desarrollo tecnológico y su implementación efectiva. En este artículo los autores subrayan en primer lugar la importancia del liderazgo en la fase actual de implantación y aceptación del eLearning, y los punto claves sobre los que se debe de sustentar. En segundo lugar explican las características de las acciones formativas online, y su engarce en un Campus Virtual. En tercer lugar se explican las características tecnológicas del eLearning. Finalmente recalcan la necesidad de un eMarket para asegurar que lo altos costes de una nueva metodología, son sostenibles.
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