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This paper analyzes the results through MEF simulation of the radiation pattern of a HyperLOG antenna and the incidence generated by being placed in a carbon fiber UAV. the simulation tool MEF (finite element method) used was ANSYS HFSS and selected a frequency of 491MHz according to the standard DVB-T2 (Digital Video Broadcasting Terrestrial, second edition), being able to observe changes in the radiation patterns simulated in 2D and 3D in horizontal and vertical plane obtaining a characterization of the antenna by means of figures of gain normalized in dB. these results allow us to confirm the affectation of the radiation pattern of the HyperLOG antenna in the presence of the structure of the UAV as a measurement device to take coverage test of the DVB-T2 singals .

In this paper, Computational Fluid Dynamics (CFD) is used to perform a transient analysis of physical variables associated with aerodynamic behavior in unmanned aerial vehicle (UAV). The simulation is used to observe vortex, pressure and turbulence kinetic energy (TKE) with post-processing. These variables facilitate the aerodynamic evaluation in aerial devices. CFD studies are currently being conducted to improve efficiency in a large number of devices such as wind turbines, aircraft and, as in our case, unmanned aerial vehicles. It was observed how the aerodynamic behavior in the Hexacopter varies in time and that there is an impact when using four and two blades in its rotors. In this simulation show the turbulence and variation in the pressure on the structure of the arms, achieving a study to propose future applications that seek the reduction of the overpressure and use of the generated turbulence.

El documento presenta un análisis de las características de transmisión multimedial sobre Internet y las características de las transmisiones de tipo multicast sobre un ambiente de comunicaciones cliente-servidor. Como conclusión de la investigación, se incluye un análisis de los resultados obtenidos a partir de la implementación de varios protocolos de enrutamiento con características de transmisión a nivel multicast para el transporte de audio como modelo propuesto para ser implementado en la red académica Rumbo. Los resultados son parte del proyecto adelantado en la línea de redes y convergencias NGN en el Grupo de Investigación e Interoperabilidad de Redes Académicas (Giira), de la Universidad Distrital.

In this paper we present a mathematical model of the kindling phenomenon, and of the electronic system that permits the installation in the animal of an epileptic model developed by Goddard et al. [1967]. This model consists in obtaining by means of electrical stimulation in the amygdala of the cat, a paroxistic progressive activation that produces the apparition of postdischarge, which follows amplitude patterns of duration and frequency representing epileptic status. We also present an electronic system designed and built for the purpose of using it in electrical stimulation with special characteristics for the pulse width, train duration, frequency and amplitude, which will produce paroxismic discharges when stimulating a certain zone of the central nervous system (specially the amygdala).

Presents a two dimensional 16 electrodes electrical impedance tomography (EIT) system, that the authors are developing by using an electronic circuit for adaptive voltage measurement, in order to apply it to epilepsy research. Simulations of epileptic status and other brain pathologies are simulated by using the RC circuit phantom (see J. Rosell et al., Proc. 11th Int. Ann. Conf. IEEE Eng. in Med. and Biol. Soc., Seattle, vol. 11 p. 459-60, 1989).

Este articulo presenta una metodología que busca estimar el comportamiento de la demanda delos usuarios residenciales y de las pérdidas en la redfrente a los cambios de tensión del Nivel I'.Partiendo de la caracterización del consumo de aparatos electrodomésticos, como una funciónde la tensión de servicio, se aplica un método general quepermite obtener una mejor aproximaciónal comportamiento de la carga, en comparación con los modelos actualmente utilizados.

Reading should be the cornerstone of a school’s curriculum in order to build up the other skills. Despite the fact that reading tends to be an obligation and a hard task, it should be seen as a fun activity which will extend the student’s knowledge of the world. Reading efficiently in volves not only understanding, speed and fluency, but also the application of the student’s knowledge, thus promoting critical thinking. That is to say, the “ability to reach sound conclusions based on observation and information”. Due to the importance of acquiring reading skills in a foreign language, we see the necessity to stimulate students toward becoming efficient readers. That means avoiding word by word reading (Williams: 1984), and developing students’ abilities to understand and comprehend a text and to read fluently

La necesidad de conocer el comportamiento del tráfico es indispensable para predecir el comportamiento de la red, modificando parámetros que permitan optimizar el uso de los recursos. La evaluación de la asignación de recursos permite conocer el comportamiento del tráfico en cada enlace determinando el rendimiento y calidad del servicio de la red. El presente trabajo busca encontrar las ventajas y desventajas del protocolo RSVP-TE cuando trabaja en una red MPLS con aplicaciones de tipo Multicast. The need to know the behavior of the traffic is essential to predict the behavior of the network, modifying parameters that allow optimizing the use of resources. The evaluation of the allocation of resources allows knowing the behavior of the traffic in each link determining the performance and quality of the network service. The present work seeks to find the advantages and disadvantages of the RSVP-TE protocol when working in an MPLS network with Multicast applications.