14 research outputs found

    Modeling, Simulation and Implementation of Chaotic Oscillator Switched by Parts

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    En el presente artículo se presenta el análisis, modelamiento, simulación e implementación de un circuito que describe un oscilador caótico en un sistema conmutado continuo por tramos (OCCCT); se obtiene el sistema de ecuaciones diferenciales que lo modelan, y se implementa la aproximación de la solución por el método de descomposición de Adomian (ADM). En consecuencia, se obtiene el correspondiente desarrollo matemático del sistema que modela el fenómeno. Para observar la presencia de caos, se obtienen los exponentes de Lyapunov y se analizan tanto las variables de salida como el diagrama de fase que estas generan. Con la solución teórica -analítica y aproximada- del sistema, se realiza una comparación con los datos obtenidos en la simulación y la arrojada por la implementación del circuito.This article presents the analysis, modeling, simulation, and implementation of a circuit that describes a chaotic oscillator in a switched continuous system by sections (OCCCT); Gets the system of differential equations that model it, and the approximation of the solution is implemented by the method of decomposition of Adomian (ADM). As a result, gets the corresponding mathematical development of the system that models the phenomenon. To observe the presence of chaos, the Lyapunov exponents are obtained and analyzed both output variables and the phase diagram that they generate. With the theoretical - analytical and approximate - system solution, is a comparison with data obtained from the simulation and the thrown by the implementation of the circuit

    Sintetización del oscilador caótico conmutado por tramos: comparación de las soluciones

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    In the present article there are described the results of the investigation that led to the analysis, modeling, simulation and implementation of a chaotic oscillator in a continuous commutated system by sections (OCCCT). Gets the system of differential equations that model it, and implements an approximation of such a solution by the method of decomposition of Adomian (ADM). Alternatively linked to the theoretical synthesis, is used as a novelty an equivalent circuit which is extracted a solution of experimental type of OCCCT. To observe the presence of chaos applies the criterion of the eigenvalues complex of space of states. With the solutions - theoretical: analytical and approximate, and experimental basis - the system a comparison is made in a particular domain that results in a correspondence admissible between themEn el presente artículo se describen los resultados de la investigación que condujo al análisis, modelamiento, simulación e implementación de un oscilador caótico en un sistema conmutado continuo por tramos (OCCCT). Se obtiene el sistema de ecuaciones diferenciales que lo modelan, y se implementa una aproximación de tal solución por el método de descomposición de Adomian (ADM). Como alternativa ligada a la síntesis teórica, se emplea como novedad un circuito equivalente del cual se extrae una solución de tipo experimental del OCCCT. Para observar la presencia de caos se aplica el criterio de los valores propios complejos del espacio de estados. Con las soluciones –teórica: analítica y aproximada, y la experimental- del sistema se realiza una comparación en un dominio concreto que arroja como resultado una correspondencia admisible entre ella

    Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

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    Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis

    The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

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    Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

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    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

    Sintetización del oscilador caótico conmutado por tramos: comparación de las soluciones

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    In the present article there are described the results of the investigation that led to the analysis, modeling, simulation and implementation of a chaotic oscillator in a continuous commutated system by sections (OCCCT). Gets the system of differential equations that model it, and implements an approximation of such a solution by the method of decomposition of Adomian (ADM). Alternatively linked to the theoretical synthesis, is used as a novelty an equivalent circuit which is extracted a solution of experimental type of OCCCT. To observe the presence of chaos applies the criterion of the eigenvalues complex of space of states. With the solutions - theoretical: analytical and approximate, and experimental basis - the system a comparison is made in a particular domain that results in a correspondence admissible between themEn el presente artículo se describen los resultados de la investigación que condujo al análisis, modelamiento, simulación e implementación de un oscilador caótico en un sistema conmutado continuo por tramos (OCCCT). Se obtiene el sistema de ecuaciones diferenciales que lo modelan, y se implementa una aproximación de tal solución por el método de descomposición de Adomian (ADM). Como alternativa ligada a la síntesis teórica, se emplea como novedad un circuito equivalente del cual se extrae una solución de tipo experimental del OCCCT. Para observar la presencia de caos se aplica el criterio de los valores propios complejos del espacio de estados. Con las soluciones –teórica: analítica y aproximada, y la experimental- del sistema se realiza una comparación en un dominio concreto que arroja como resultado una correspondencia admisible entre ella

    XVII International Congress of Control Electronics and Telecommunications: "Advanced Science, Technology and Innovation to move towards a new socio-technical system: Sustainable Social Transformation"

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    Contenido: Approach to the diagnostic of cesarean birth using bio-inspired models. ; Design of a tool in a virtual reality environment to manipulate anatomical models. ; The effect of COVID-19 restrictions on the electricity price forecasting models. ; Depression prevention through artificial intelligence. ; State of the art in Prototypes as complements to the learning of the Colombian Sign Language (LSC). ; A computational proposal for gene expression deterministic analysis in associated disorders to depression and anxiety. ; Evaluation of postural stability from the predictability of the measurement of the center of pressure. ; Psychophysiological Analysis of Sound Stimuli.; Delphi method for the identification of relevant variables in the development of low-power photovoltaic solar projects. ; Socioeconomic impact of a refrigerator powered by a photovoltaic system in La Guajira. ; Energy Efficiency: characteristics that allow the reduction of greenhouse gases in. ; Possibilities for the implementation of a bioreactor from organic waste. ; Energy Potential with Small Hydroelectric Power Plants in Non- interconnected Zones of Colombia. ; Energy Potential in Photovoltaic Solar Solutions in Non-Interconnected Areas of Colombia. ; Photovoltaic system, towards the energy transition from home. ; Blockchain model to increase the transparency of public sector processes. ; Intelligent agricultural irrigation prescription system based on sensor networks and crop modeling. ; Design and implementation of a digital modulation classification system using intelligent algorithms. ; A mobile application proposal to minimize intermediation during agricultural process distribution of products in supply chain. ; Accompanying strategy for the social appropriation of new technologies in vulnerable agricultural communities: case in communities producing Gulupas fruits (Passiflora edulis Sims). ; Predictive model of transparency as an indicator of Public Policies. ; Smart system for recognition of ripening level in blackberry fruits. ; Project-based learning as an alternative methodology for technological education in electronics. ; Design and construction of an automated system for N. ; Four bar mechanisms (FBM) and their Software-Based applications: a reviewFT aquaponic culture of Red Carp and Crespa Lettuce. ; Intelligent search implementation for the construction of states of the art: a python application. ; Indoor and Outdoor propagation models on 5G environments: state of the art. ;The electronic detection of offenders (DOO) in the District Secretary of mobility of Bogotá: a step forward in the configuration of the concept of digital citizenship in Colombia. ; Monitoring through ICT of Mobility: technological collaborative feature to incorporate IoT in a Smart City. ; Characterization model of asphalt mixtures using digital image processing. ; Review: identification of diseases and/or pests in fruit trees through image processing techniques and artificial intelligence. ; VRS applicated to Nasa Yuwe language. ; Application of Pix2Pix for edge reconstruction in images. ; Brushless DC Motor Control System for Active Myoelectric Prosthesis. ; Implementation of a Water Conductivity Measuring System. ; 2 DOF robot programmed with MatLab® (guide and Peter Corke) and Arduino uno for writing alphabetical characters. ; Simulator of the behavior of the center of mass in a quadruped robot. ; Biomimetic prototype for flapping movement of batsContent: Contenido: Approach to the diagnostic of cesarean birth using bio-inspired models. ; Design of a tool in a virtual reality environment to manipulate anatomical models. ; The effect of COVID-19 restrictions on the electricity price forecasting models. ; Depression prevention through artificial intelligence. ; State of the art in Prototypes as complements to the learning of the Colombian Sign Language (LSC). ; A computational proposal for gene expression deterministic analysis in associated disorders to depression and anxiety. ; Evaluation of postural stability from the predictability of the measurement of the center of pressure. ; Psychophysiological Analysis of Sound Stimuli.; Delphi method for the identification of relevant variables in the development of low-power photovoltaic solar projects. ; Socioeconomic impact of a refrigerator powered by a photovoltaic system in La Guajira. ; Energy Efficiency: characteristics that allow the reduction of greenhouse gases in. ; Possibilities for the implementation of a bioreactor from organic waste. ; Energy Potential with Small Hydroelectric Power Plants in Non- interconnected Zones of Colombia. ; Energy Potential in Photovoltaic Solar Solutions in Non-Interconnected Areas of Colombia. ; Photovoltaic system, towards the energy transition from home. ; Blockchain model to increase the transparency of public sector processes. ; Intelligent agricultural irrigation prescription system based on sensor networks and crop modeling. ; Design and implementation of a digital modulation classification system using intelligent algorithms. ; A mobile application proposal to minimize intermediation during agricultural process distribution of products in supply chain. ; Accompanying strategy for the social appropriation of new technologies in vulnerable agricultural communities: case in communities producing Gulupas fruits (Passiflora edulis Sims). ; Predictive model of transparency as an indicator of Public Policies. ; Smart system for recognition of ripening level in blackberry fruits. ; Project-based learning as an alternative methodology for technological education in electronics. ; Design and construction of an automated system for N. ; Four bar mechanisms (FBM) and their Software-Based applications: a reviewFT aquaponic culture of Red Carp and Crespa Lettuce. ; Intelligent search implementation for the construction of states of the art: a python application. ; Indoor and Outdoor propagation models on 5G environments: state of the art. ;The electronic detection of offenders (DOO) in the District Secretary of mobility of Bogotá: a step forward in the configuration of the concept of digital citizenship in Colombia. ; Monitoring through ICT of Mobility: technological collaborative feature to incorporate IoT in a Smart City. ; Characterization model of asphalt mixtures using digital image processing. ; Review: identification of diseases and/or pests in fruit trees through image processing techniques and artificial intelligence. ; VRS applicated to Nasa Yuwe language. ; Application of Pix2Pix for edge reconstruction in images. ; Brushless DC Motor Control System for Active Myoelectric Prosthesis. ; Implementation of a Water Conductivity Measuring System. ; 2 DOF robot programmed with MatLab® (guide and Peter Corke) and Arduino uno for writing alphabetical characters. ; Simulator of the behavior of the center of mass in a quadruped robot. ; Biomimetic prototype for flapping movement of bat

    XV International Congress of Control Electronics and Telecommunications: "The role of technology in times of pandemic and post-pandemic: innovation and development for strategic social and productive sectors"

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    La anterior selección, motivados por la aseveración de Manuel Castells -hace casi 20 años ya- que la innovación y la difusión de la tecnología parecía ser la herramienta apropiada para el desarrollo en la era de la información. Este 2020, sin embargo, ante la situación disruptiva que aquejó y aqueja a la sociedad red como una estructura social emergente de la Era de la Información basada en redes de producción, energizadas por el poder y la experiencia; falló y debe reencontrar su rumbo. Es así que los problemas acuciantes, ahora, fueron: la atención sanitaria y la superación de la epidemia de Sars Cov 2; tomó forma la, hasta entonces, visión irrealista de Castells que … no podemos avanzar con nuestros modelos de desarrollo actual, destruyendo nuestro entorno y excluyendo a la mayor parte de la humanidad de los beneficios de la revolución tecnológica más extraordinaria de la historia, sin sufrir una devastadora reacción por parte de la sociedad y la naturaleza. Fue así que el Cuarto Mundo, específicamente, donde la suficiencia de recurso humano, de capital, trabajo, información y mercado -vinculados todos a través de la tecnología- supuso que atendería eficazmente a través de la población que podía por su capacidad hacer uso racional y profesional del conocimiento, las necesidades de la mayoritaria población vulnerable y vulnerada. Por lo anterior, poner en el centro a las personas, en entornos de tarea y trabajo globales hiperconectados combinando espacios físicos, corrientes de información con canales de conexión expeditos, y formando profesionales del conocimiento que asuman y afronten los retos derivados de la transformación digital de empresas, universidades, y organizaciones, pero en condiciones de equidad y sujetos de prosperidad, será el desafío en los escenarios presentes y futuros inmediatos.The previous selection, motivated by the assertion of Manuel Castells -almost 20 years ago- that innovation and diffusion of technology seemed to be the appropriate tool for development in the information age. This 2020, however, in the face of the disruptive situation that afflicted and continues to afflict the network society as an emerging social structure of the Information Age based on production networks, energized by power and experience; He failed and must find his way again. Thus, the pressing problems now were: health care and overcoming the Sars Cov 2 epidemic; Castells' until then unrealistic vision took shape that... we cannot advance with our current development models, destroying our environment and excluding the majority of humanity from the benefits of the most extraordinary technological revolution in history, without suffering a devastating reaction from society and nature. It was thus that the Fourth World, specifically, where the sufficiency of human resources, capital, work, information and market - all linked through technology - meant that it would serve effectively through the population that could, due to its capacity, make rational use. and knowledge professional, the needs of the majority vulnerable and vulnerable population. Therefore, putting people at the center, in hyperconnected global task and work environments, combining physical spaces, information flows with expedited connection channels, and training knowledge professionals who assume and face the challenges derived from the digital transformation of companies, universities, and organizations, but in conditions of equality and subject to prosperity, will be the challenge in the present and immediate future scenarios.Bogot

    70º Aniversario de la declaración universal de derechos humanos. La protección internacional de los Derechos Humanos en cuestión

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    Segundo volúmen de la Colección Perspectivas Iberoamericanas sobre la justicia. La Declaración Universal de los Derechos Humanos de las Naciones Unidas cumple, el 10 de diciembre de 2018, setenta años. La simbólica fecha obliga a los investigadores en derechos humanos a reflexionar críticamente sobre los avances y límites de un complejo sistema de normas y, sobre todo, de valores culturales sustentados en la matriz liberal occidental. Desde entonces, ha habido indiscutibles avances institucionales y normativos, como la creación del Consejo de Derechos Humanos, varios pactos y declaraciones complementarias, órganos específicos, tribunales internacionales, jurisprudencia, constituciones estatales, una infinidad de instituciones basadas en esta “ética mínima universal” que, contradictoriamente, no logró evitar un conjunto de catástrofes humanitarias y de vulneración de derechos. La primera década del siglo XX trae un reflejo limitante al consenso de la posguerra, pues la agresividad de los Estados hegemónicos, en alianza con intereses privados transnacionales, pone en jaque la capacidad del sistema protector frente a guerras humanitarias e internacionales. tratados económicos de nueva generación aquellos que excluyen por completo a la democracia del proceso de negociación.A Declaração Universal dos Direitos Humanos das Nações Unidas completa, em 10 de diciembre de 2018, setenta años. A data simbólica exige dos pesquisadores em direitos humanos uma reflexão crítica a respeito dos avanços y dos limites de um sistema complexo de normas e, principalmente, de valores culturales apoiados na matriz liberal ocidental. De lá para cá, houve indiscutível avanço institucional e normativo, do qual é exemplo a criação do Conselho de Direitos Humanos, diversos pactos e declarações complementarios, órgão específicos, tribunais internacionais, jurisprudência, constituições dos States, uma infinidade de instituições pautadas nesse “mínimo ético universal” que, contraditoriamente, não conseguiu evitar um conjunto de catástrofes humanitárias e de violação de direitos. A primeira década do século XX traz uma reflexão limite para o consenso do pós-guerra, pois a agressividade dos States hegemônicos, em aliança com interesses private transnacionais, põe em check a capacidade do sistema protectivo diante das guerras humanitárias e dos tratados internacionais econômicos de nueva generación aqueles que excluem completamente a democracia do processo negociador
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