29 research outputs found
Model-based guidance and control for atmospheric guided entry
This paper presents a solution of the translational control for a biconic atmospheric entry
capsule using the bank angle as a command. The control algorithm is separated into path
planning and reference-path tracking. The path-planning algorithm computes the entry
trajectory from the navigated state at the Entry Interface Point until the desired Parachute
Deployment Point. The algorithm aims to recover the landing site uncertainty caused by
Entry Interface Point dispersions. Atmospheric and aerodynamic dispersions are
compensated in real-time following the Embedded Model Control methodology in which
parametric uncertainty is estimated and rejected as an external disturbance. A hierarchical
control structure is designed for facilitating non-linear dynamic inversion of the
altitude/density relation and tuning of noise estimators and control laws. Both path planning
and reference-path tracking exploit longitudinal and lateral decomposition of the
translational dynamics, as well as state equation linearization around a reference trajectory.
The main concepts and solutions of the algorithms are presented without formal proofs of
convergence, performance and stability. The results of a Monte Carlo simulation campaign
conducted on a high fidelity simulator are provided and discussed
Implementación de servicios de infraestructura TI corporativa con Zentyal Server 5.
Se presenta la implementación de servicios esenciales de infraestructura TI para redes, instalando y configurando la distribución GNU/Linux Zentyal Server. Dentro de los servicios configurados que ofrece se encuentran: El protocolo de configuración dinámica (DHCP) y el servicio de nombres de dominio (DNS) para proveer la conectividad y administración básica a los dispositivos de la red; el servicio de controlador de dominio, el proxy para acceso a la web, el cortafuegos (Firewall) y la red privada virtual (VPN) para obtener varios niveles de seguridad y acceso controlado a los servicios y recursos de la red e internet; y, finalmente, los servidores de archivos y de impresión, con el fin de incrementar la productividad aprovechando la red para compartir los recursos corporativos. Zentyal Server provee una solución integral y robusta a las necesidades tecnológicas en red de pequeñas y medianas empresas reduciendo la dificultad natural de los sistemas GNU/Linux.Using the GNU/Linux Zentyal Server distribution, this work shows the implementation of essential IT infrastructure services for corporative networks, such as the dynamic hosts configuration protocol (DHCP) and the domain name service (DNS) to provide connectivity and basic administration to network devices; the domain controller service, the proxy for accessing the web, the firewall and the virtual private network (VPN) to add a higher level of security and controlled access to the services and resources inside the internal the network and internet; and, finally, the file and print servers, in order to increase productivity by leveraging the network to share corporate resources. Zentyal Server provides a comprehensive and robust solution to the technological needs for small and medium-sized businesses by reducing the natural difficulty found on GNU/Linux systems
EXTRACCIÓN DE PIGMENTOS APARTIR DE CULTIVO IN VITRO DE MICROALGAS: ALTERNATIVA A LA SÍNTESIS QUÍMICA DE COLORANTES
La síntesis química de colorantes del sector textil genera residuos tóxicos que afectan al entorno que rodea a estas industrias, causando contaminación hídrica, del suelo y atmosférica, con múltiples afectaciones en la salud humana y de los ecosistemas, siendo la alternativa a este problema: los pigmentos obtenidos a partir de microalgas. El objetivo de esta investigación es extraer pigmentos partiendo del cultivo in vitro de las microalgas Chlorella spp y Scenedesmus spp con medio F/2. La extracción de los pigmentos es asistida por ultrasonido y un peso seco
EXTRACCIÓN DE PIGMENTOS APARTIR DE CULTIVO IN VITRO DE MICROALGAS: ALTERNATIVA A LA SÍNTESIS QUÍMICA DE COLORANTES
La síntesis química de colorantes del sector textil genera residuos tóxicos que afectan al entorno que rodea a estas industrias, causando contaminación hídrica, del suelo y atmosférica, con múltiples afectaciones en la salud humana y de los ecosistemas, siendo la alternativa a este problema: los pigmentos obtenidos a partir de microalgas. El objetivo de esta investigación es extraer pigmentos partiendo del cultivo in vitro de las microalgas Chlorella spp y Scenedesmus spp con medio F/2. La extracción de los pigmentos es asistida por ultrasonido y un peso seco
Risk factors for developing ventilator-associated lower respiratory tract infection in patients with severe COVID-19:a multinational, multicentre study, prospective, observational study
Around one-third of patients diagnosed with COVID-19 develop a severe illness that requires admission to the Intensive Care Unit (ICU). In clinical practice, clinicians have learned that patients admitted to the ICU due to severe COVID-19 frequently develop ventilator-associated lower respiratory tract infections (VA-LRTI). This study aims to describe the clinical characteristics, the factors associated with VA-LRTI, and its impact on clinical outcomes in patients with severe COVID-19. This was a multicentre, observational cohort study conducted in ten countries in Latin America and Europe. We included patients with confirmed rtPCR for SARS-CoV-2 requiring ICU admission and endotracheal intubation. Only patients with a microbiological and clinical diagnosis of VA-LRTI were included. Multivariate Logistic regression analyses and Random Forest were conducted to determine the risk factors for VA-LRTI and its clinical impact in patients with severe COVID-19. In our study cohort of 3287 patients, VA-LRTI was diagnosed in 28.8% [948/3287]. The cumulative incidence of ventilator-associated pneumonia (VAP) was 18.6% [610/3287], followed by ventilator-associated tracheobronchitis (VAT) 10.3% [338/3287]. A total of 1252 bacteria species were isolated. The most frequently isolated pathogens were Pseudomonas aeruginosa (21.2% [266/1252]), followed by Klebsiella pneumoniae (19.1% [239/1252]) and Staphylococcus aureus (15.5% [194/1,252]). The factors independently associated with the development of VA-LRTI were prolonged stay under invasive mechanical ventilation, AKI during ICU stay, and the number of comorbidities. Regarding the clinical impact of VA-LRTI, patients with VAP had an increased risk of hospital mortality (OR [95% CI] of 1.81 [1.40-2.34]), while VAT was not associated with increased hospital mortality (OR [95% CI] of 1.34 [0.98-1.83]). VA-LRTI, often with difficult-to-treat bacteria, is frequent in patients admitted to the ICU due to severe COVID-19 and is associated with worse clinical outcomes, including higher mortality. Identifying risk factors for VA-LRTI might allow the early patient diagnosis to improve clinical outcomes. Trial registration: This is a prospective observational study; therefore, no health care interventions were applied to participants, and trial registration is not applicable
Annual Conference on Formative Research on EFL. Practices thar inspire change.
The conference papers of the Annual Conference on Formative
Research on EFL. Practices thar inspire change collect pedagogical
experiences, research reports, and reflections about social issues,
language teaching, teaching training, interculturality under the
panorama of the Covid-19 pandemic. Each paper invites the reader
to implement changes in their teaching practice through
disruptive pedagogies, reflect on the social and emotional
consequences of the lockdown, new paths for teacher training and
different approaches for teaching interculturality. We expect to
inspire new ways to train pre-service teachers and teach
languages in this changing times