Closed-loop stabilization of a class of Lur'e system: application to chaos control

"In this paper the problem of closed-loop stabilization of a class of Lur'e system is addressed. Under certain conditions of the static non-linearity, the control problem is proved that can be converted to a simultaneous stabilization condition for a linear controller. The design strategy is considered for chaos control of a type of C3—equivalents chaotic systems. Experimental results corroborate the analysis presented.

The antecedents of export performance of Brazilian small and medium-sized enterprises (SMEs): The non-linear effects of customer orientation

This article examines the determinants of customer orientation and the quadratic effects of customer orientation on export performance. The relationship between customer orientation and export performance has been assumed to have a linear relationship, neglecting the possibility of non-linear relationships. While most studies have been conducted in developed countries, we test our model in Brazil, an emerging market economy. The findings suggest that technology intensity and competitive intensity are key determinants in explaining success in an export market. Our findings also indicate that the relationship between customer orientation and export performance is quadratic (U-shaped) rather than linear. The implications of these findings are discussed

Assessment of compressibility effects on internal nozzle flow in diesel injectors at very high injection pressures

[EN] Diesel fuel injection systems are being used at higher injection pressure conditions over time because of more stringent emissions requirements. Thus, the importance to properly take into account the fluid compressibility on injection CFD simulations is also increasing. In this paper, an investigation of the compressibility effects in nozzle flow simulations has been carried out for injection pressures up to 250 MPa. To do so, the fluid properties (including density, viscosity and speed of sound) have been measured in a wide range of boundary conditions. These measurements have allowed to obtain correlations for the fluid properties as a function of pressure and temperature. Then, these equations have been incorporated to a CFD solver to take into account the variation of the fluid properties with the pressure changes along the computational domain. The results from these simulations have been compared to experimental mass flow rate and momentum flux results, showing a significant increase in accuracy with respect to an incompressible flow solution.This work was partly sponsored by "Ministerio de Economia y Competitividad", of the Spanish Government, in the frame of the Project "Estudio de la interaccion chorro-pared en condiciones realistas de motor", Reference TRA2015-67679-c2-1-R. The authors would like also to thank the computer resources, technical expertise and assistance provided by Universidad de Valencia in the use of the supercomputer "Tirant". Mr. Jaramillo's Thesis is funded by "Conselleria d'Educacio, Cultura i Esports" of Generalitat Valenciana in the frame of the program "Programa VALI+D para investigadores en formacion, Reference ACIF/2015/040.Salvador, F.; De La Morena, J.; Martínez López, J.; Jaramillo-Císcar, D. (2017). Assessment of compressibility effects on internal nozzle flow in diesel injectors at very high injection pressures. Energy Conversion and Management. 132:221-230. https://doi.org/10.1016/j.enconman.2016.11.03222123013

Análisis de los factores formadores y distribución de los suelos en la Sierra del Rayo (Granada)

Se realiza un análisis del medio físico: Relieve, Material original y Clima de los suelos que existen en la Sierra del Rayo, así como una cartografía detallada de los mismos, expresando las unidades de suelo que se contemplan en la zona.It has been made an analysis of the Physical medium (relief, parent material and climate) on the soils of Sierra del Rayo (Granada), which its detailed cartography, expressing also the soil units which appear in the zone

Effect of Greenhouse Film Cover on the Development of Fungal Diseases on Tomato (Solanum lycopersicum L.) and Pepper (Capsicum annuum L.) in a Mediterranean Protected Crop

Greenhouses on the Mediterranean coast mainly use plastic materials as their cover. The influence of light exerted by these materials directly affects the crops by modifying the environment in which they develop. The aim of this study was to analyze the effect of the use of two plastic films in an experimental greenhouse on the development of fungal diseases in two spring–summer crop cycles: tomato (Solanum lycopersicum L.) from february to July 2021 and pepper (Capsicum annuum L.) from February to July 2022. The study was carried out in Almeria (Spain) in a multispan greenhouse divided transversely into two sectors by a polyethylene sheet. A commercial film was installed in the east sector (90% of transmissivity and 55% diffusivity) and an experimental film was installed in the west sector (85% of transmissivity and 60% diffusivity). In addition, the effect of the yield and quality of the harvested fruit was determined. In this study, two diseases were established naturally on the crop: (i) powdery mildew (Leveillula taurica) in both the tomato and the pepper crop cycles and (ii) early blight (Alternaria solani) in the tomato. The analyses of both diseases showed that the areas of the greenhouse that used the plastic cover, which presented a lower sunlight transmissivity, showed higher levels of disease than the areas that used the plastic cover that allowed greater transmissivity of light within the greenhouse, differing statistically in some phases of the crop. The marketable yield was 4.2% (for tomato) and 3.1% (for pepper) higher in the sector with the experimental film with high transmissivity. For both crops, the quality of the fruits did not show statistically significant difference

Why fly blind? Event-based visual guidance for ornithopter robot flight

Under licence Creative Commons - Green Open Access (IEEE).The development of perception and control methods that allow bird-scale flapping-wing robots (a.k.a. ornithopters) to perform autonomously is an under-researched area. This paper presents a fully onboard event-based method for ornithopter robot visual guidance. The method uses event cameras to exploit their fast response and robustness against motion blur in order to feed the ornithopter control loop at high rates (100 Hz). The proposed scheme visually guides the robot using line features extracted in the event image plane and controls the flight by actuating over the horizontal and vertical tail deflections. It has been validated on board a real ornithopter robot with real-time computation in low-cost hardware. The experimental evaluation includes sets of experiments with different maneuvers indoors and outdoors.Consejo Europeo de Investigación (ERC) 78824

The Education of the System of Documentation for the student of the Pregrate of Q.F.B in the Fes Zaragoza Unam

Introducción. La carrera Química Farmacéutico Biológica (QFB), cuenta con una Planta Piloto Farmacéutica (PPF) como un recurso del proceso enseñanza-aprendizaje, para el fortalecimiento del conocimiento donde uno de sus puntos esenciales es la documentación. El Sistema de Documentación está destinado a que el estudiante desarrolle actividades experimentales y deje evidencia documentada como lo estipula la reglamentación sanitaria vigente. Objetivo. Presentar la metodología que apoya el proceso de enseñanza aprendizaje del Sistema de Documentación a los alumnos del área Farmacéutica. Metodología. Inducción al tema de documentación mediante exposición oral, dando a conocer los diferentes documentos como son: Manual de laboratorio, Procedimientos Normalizados de Operación, entre otros. Cada profesor revisa los documentos generados durante el semestre, y sugiere mejoras en el caso requerido. Resultados. Con base a una evaluación interna, se observa un avance en el conocimiento y aplicación del Sistema Documental, entre los alumnos de sexto a noveno semestre. Conclusión. Al poner en práctica lo establecido en los documentos, se contribuye a la disciplina de la elaboración, difusión y aplicación del Sistema de Documentación, al establecer procesos y flujos que la conforman.Introduction. The race of Pharmaceutical Biological Chemistry (QFB), has a Pharmaceutical Pilot Plant (PPF) as a resource in the teaching-learning process for the strengthening of knowledge where one of his key points is the documentation. The documentation system is designed to enable the student to develop pilot activities and allow documentary evidence as required by health regulations in force. Objective. Present the methodology that supports the teaching-learning process Documentation System for Pharmaceutical area students. Methodology. Induction to the issue of documentation through oral exposure, revealing the various documents such as: laboratory manual, standard operating procedures, among others. Each teacher reviews the documents generated during the semester, and suggest improvements if required. Results. Based on an internal evaluation, there is an advance in knowledge and implementation of the Documentation System, among students in sixth through ninth semester. Conclusion. In implementing the provisions of the documents, it contributes to the discipline of the preparation, dissemination and implementation of documentation systems, to establish processes and flows that make it up

Educación y cooperación para el desarrollo mediante estándares universales de accesibilidad

II FORO «IBEROAMÉRICA EN LA ESCENA ECONÓMICA INTERNACIONAL: INVERSIONES Y EDUCACIÓN PARA EL DESARROLLO». UNIVERSIDAD REY JUAN CARLOS, MADRID (ESPAÑA), 14 DE DICIEMBRE DE 200

Accesibilidad a Internet: requisitos para la calidad en la docencia e investigación

A good Internet platform for teaching and research must be accessible, independently of the computer platform used, language and other peculiarities (personal or external). This work analyzes the current limitations of Internet access, as well as the potentialities that would represent an access being truly independent of the computer platform, discapacities, availability and speed of access, language and legislation. Thus, the benefits for a more accesible network for lecturing and investigation, overcoming the geographic location or possible discapacity, would be immediate and would have a broad impact spectrum. A more accesible Internet would enhace not only the dissemination of the information, approaching us to the 'global village', but also others aspects like university principles and values that sould be considered: an improvement of the equality of opportunities and the access to the culture and the education, that are the basis of the progress and the individual and collective liberties.Una buena plataforma de docencia e investigación en la red debe ser accesible, independientemente del entorno informático, idioma y condicionantes( personales o externos). Es este trabajo se analizan, por una parte, las limitaciones actuales que se presentan en el acceso a Internet, y por otra las potencialidades que tendría un acceso un acceso independiente de las plataforma informáticas, discapacidades, disponibilidad y velocidad de acceso, idioma y legislación. Así, los beneficios para la docencia y la investigación de una red más accesible, por encima de la localización geográfica o posible discapacidad, serán inmediatos y redundaría en otros campos. Una Internet más accesible abriría una nueva vía no sólo para la difusión de la información, acercándonos a la 'aldea global', sino también para otros aspectos de lo que entenderemos como principios y valores universitarios y que deben ser considerados: una mejora en la igualdad de oportunidades y en el acceso a la cultura y la formación, que son las bases del progreso y de las libertades tanto individuales como colectivas