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| Author | Morocho-Cayamcela, M.E. & W. Lim | ||||
| Title | Lateral confinement of high-impedance surface-waves through reinforcement learning | Type | Journal Article | ||
| Year | 2020 | Publication | Electronics Letters | Abbreviated Journal | |
| Volume | Vol. 56 | Issue | 23, 12 November 2020 | Pages | pp. 1262-1264 |
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| Abstract | The authors present a model-free policy-based reinforcement learning model that introduces perturbations on the pattern of a metasurface. The objective is to learn a policy that changes the size of the patches, and therefore the impedance in the sides of an artificially structured material. The proposed iterative model assigns the highest reward when the patch sizes allow the transmission along a constrained path and penalties when the patch sizes make the surface wave radiate to the sides of the metamaterial. After convergence, the proposed model learns an optimal patch pattern that achieves lateral confinement along the metasurface. Simulation results show that the proposed learned-pattern can effectively guide the electromagnetic wave through a metasurface, maintaining its instantaneous eigenstate when the homogeneity is perturbed. Moreover, the pattern learned to prevent reflections by changing the patch sizes adiabatically. The reflection coefficient S1, 2 shows that most of the power gets transferred from the source to the destination with the proposed design. |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 139 | ||
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| Author | Miguel A. Murillo, Julio E. Alvia, & Miguel Realpe | ||||
| Title | Beyond visual and radio line of sight UAVs monitoring system through open software in a simulated environment. | Type | Conference Article | ||
| Year | 2021 | Publication | The 2nd International Conference on Applied Technologies (ICAT 2020), diciembre 2-4. Communications in Computer and Information Science | Abbreviated Journal | |
| Volume | 1388 | Issue | Pages | 629-642 | |
| Keywords | Drone, Open Source, Internet, Web Application, Web Server, SITL, Line of sight, UAV. | ||||
| Abstract | The problem of loss of line of sight when operating drones has be-come a reality with adverse effects for professional and amateur drone opera-tors, since it brings technical problems such as loss of data collected by the de-vice in one or more instants of time during the flight and even misunderstand-ings of legal nature when the drone flies over prohibited or private places. This paper describes the implementation of a drone monitoring system using the In-ternet as a long-range communication network in order to avoid the problem of loss of communication between the ground station and the device. For this, a simulated environment is used through an appropriate open software tool. The operation of the system is based on a client that makes requests to a server, the latter in turn communicates with several servers, each of which has a drone connected to it. In the proposed system when a drone is ready to start a flight, its server informs the main server of the system, which in turn gives feedback to the client informing it that the device is ready to carry out the flight; this way customers can send a mission to the device and keep track of its progress in real time on the screen of their web application. | ||||
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 186 | ||
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| Author | Charco, J.L., Sappa, A.D., Vintimilla, B.X., Velesaca, H.O. | ||||
| Title | Camera pose estimation in multi-view environments:from virtual scenarios to the real world | Type | Journal Article | ||
| Year | 2021 | Publication | In Image and Vision Computing Journal. (Article number 104182) | Abbreviated Journal | |
| Volume | Vol. 110 | Issue | Pages | ||
| Keywords | Relative camera pose estimation, Domain adaptation, Siamese architecture, Synthetic data, Multi-view environments | ||||
| Abstract | This paper presents a domain adaptation strategy to efficiently train network architectures for estimating the relative camera pose in multi-view scenarios. The network architectures are fed by a pair of simultaneously acquired images, hence in order to improve the accuracy of the solutions, and due to the lack of large datasets with pairs of overlapped images, a domain adaptation strategy is proposed. The domain adaptation strategy consists on transferring the knowledge learned from synthetic images to real-world scenarios. For this, the networks are firstly trained using pairs of synthetic images, which are captured at the same time by a pair of cameras in a virtual environment; and then, the learned weights of the networks are transferred to the real-world case, where the networks are retrained with a few real images. Different virtual 3D scenarios are generated to evaluate the relationship between the accuracy on the result and the similarity between virtual and real scenarios—similarity on both geometry of the objects contained in the scene as well as relative pose between camera and objects in the scene. Experimental results and comparisons are provided showing that the accuracy of all the evaluated networks for estimating the camera pose improves when the proposed domain adaptation strategy is used, highlighting the importance on the similarity between virtual-real scenarios. |
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English | Summary Language | English | Original Title | |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 147 | ||
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| Author | Rubio, G.A., Agila, W.E | ||||
| Title | A fuzzy model to manage water in polymer electrolyte membrane fuel cells | Type | Journal Article | ||
| Year | 2021 | Publication | In Processes Journal. (Article number 904) | Abbreviated Journal | |
| Volume | Vol. 9 | Issue | Issue 6 | Pages | |
| Keywords | PEM fuel cell, fuzzy, neural network, electrical response, flooding, drying. | ||||
| Abstract | In this paper, a fuzzy model is presented to determine in real-time the degree of dehydration or flooding of a proton exchange membrane of a fuel cell, to optimize its electrical response and consequently, its autonomous operation. By applying load, current and flux variations in the dry, normal, and flooded states of the membrane, it was determined that the temporal evolution of the fuel cell voltage is characterized by changes in slope and by its voltage oscillations. The results were validated using electrochemical impedance spectroscopy and show slope changes from 0.435 to 0.52 and oscillations from 3.6 mV to 5.2 mV in the dry state, and slope changes from 0.2 to 0.3 and oscillations from 1 mV to 2 mV in the flooded state. The use of fuzzy logic is a novelty and constitutes a step towards the progressive automation of the supervision, perception, and intelligent control of fuel cells, allowing them to reduce their risks and increase their economic benefits. | ||||
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 153 | ||
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| Author | Luis Jacome-Galarza, Monica Villavicencio-Cabezas, Miguel Realpe-Robalino, Jose Benavides-Maldonado | ||||
| Title | Software Engineering and Distributed Computing in image processing intelligent systems: a systematic literature review. | Type | Conference Article | ||
| Year | 2021 | Publication | 19th LACCEI International Multi-Conference for Engineering, Education, and Technology | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | processing, software engineering, deep learning, intelligent vision systems, cloud computing. | ||||
| Abstract | Deep learning is experiencing an upward technology trend that is revolutionizing intelligent systems in several domains, such as image and speech recognition, machine translation, social network filtering, and the like. By reviewing a total of 80 studies reported from 2016 to 2020, the present article evaluates the application of software engineering to the field of intelligent image processing systems, it also offers insights about aspects related to distributed computing for this type of systems. Results indicate that several topics of software engineering are mostly applied when academics are involved in developing projects associated to this kind of intelligent systems. The findings provide evidences that Apache Spark is the most utilized distributed computing framework for image processing. In addition, Tensorflow is a popular framework used to build convolutional neural networks, which are the prevailing deep learning algorithms used in intelligent image processing systems. Also, among big cloud providers, Amazon Web Services is the preferred computing platform across the industry sectors, followed by Google cloud. |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 154 | ||
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| Author | Angel D. Sappa; Cristhian A. Aguilera; Juan A. Carvajal Ayala; Miguel Oliveira; Dennis Romero; Boris X. Vintimilla; Ricardo Toledo | ||||
| Title | Monocular visual odometry: a cross-spectral image fusion based approach | Type | Journal Article | ||
| Year | 2016 | Publication | Robotics and Autonomous Systems Journal | Abbreviated Journal | |
| Volume | Vol. 86 | Issue | Pages | pp. 26-36 | |
| Keywords | Monocular visual odometry LWIR-RGB cross-spectral imaging Image fusion | ||||
| Abstract | This manuscript evaluates the usage of fused cross-spectral images in a monocular visual odometry approach. Fused images are obtained through a Discrete Wavelet Transform (DWT) scheme, where the best setup is em- pirically obtained by means of a mutual information based evaluation met- ric. The objective is to have a exible scheme where fusion parameters are adapted according to the characteristics of the given images. Visual odom- etry is computed from the fused monocular images using an off the shelf approach. Experimental results using data sets obtained with two different platforms are presented. Additionally, comparison with a previous approach as well as with monocular-visible/infrared spectra are also provided showing the advantages of the proposed scheme. | ||||
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Enlgish | Summary Language | English | Original Title | |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 54 | ||
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| Author | Del Pino, J.; Salazar, G.; Cedeño, V. Msc. | ||||
| Title | Adaptación de un Recomendador de Filtro Colaborativo Basado en el Usuario para la Creación de un Recomendador de Materias de Pregrado Basado en el Historial Académico de los Estudiantes | Type | Journal Article | ||
| Year | 2011 | Publication | Revista Tecnológica ESPOL | Abbreviated Journal | |
| Volume | Vol. 24 | Issue | Pages | pp. 29 - 34 | |
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| Abstract | Los sistemas de recomendación son ampliamente utilizados hoy en día gracias a su capacidad de analizar las preferencias de usuarios y sugerir ítems. No obstante, el uso de los recomendadores está limitado a un modelo basado en el usuario y no en su historial de preferencias, discriminando así el campo de aplicación, por ejemplo, a sistemas académicos donde sea primordial el estudio de las decisiones del estudiante a lo largo de su carrera. El presente trabajo presenta un esfuerzo por adaptar filtros colaborativos basados en el usuario a filtros colaborativos basados en el historial del usuario. Con un conjunto de pruebas mediremos su efectividad utilizando dos algoritmos distintos de similaridad para recomendar materias a un estudiante en el sexto semestre de la carrera de Ingeniería en Electrónica y Telecomunicaciones ofertada por la FIEC – ESPOL. Los resultados muestran que es factible adaptar un recomendador a un modelo basado en el historial del usuario |
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| Address | Campus “Gustavo Galindo Velasco” La prosperina Km 30,5 vía perimetral, Guayaquil, Ecuador | ||||
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Español | Summary Language | Español | Original Title | |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 13 | ||
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| Author | Arias Alexandra. Ing.; Peña Roxanna. Ing.; Chávez Patricia. MSEE.; Basurto Juan. Ing | ||||
| Title | Análisis Comparativo de la Implementación de una PBX de Código Abierto instalada en un Servidor Tradicional y en un Enrutador Inalámbrico en términos de Calidad de Servicio en Redes Inalámbricas Amalladas | Type | Journal Article | ||
| Year | 2011 | Publication | Revista Tecnologica ESPOL RTE | Abbreviated Journal | |
| Volume | Vol. 24 | Issue | Pages | pp. 1-6 | |
| Keywords | Redes Inalámbricas Mesh, VoIP, Asterisk | ||||
| Abstract | El presente trabajo compara dos Implementaciones de Centrales Telefónicas VoIP de Código Abierto implementados sobre una Red Inalámbrica Amallada. El primero comprende la instalación de la PBX en un servidor tradicional y el segundo la instalación de una PBX en un enrutador inalámbrico. Nuestro objetivo es determinar cuál de estos dos sistemas es superior en cuanto a calidad de servicio se refiere. Para determinar la mejor solución, realizamos un estudio técnico de los paquetes capturados durante diferentes pruebas, considerando parámetros como el ancho de banda, retardo y jitter. Nuestros métodos de análisis pueden ser utilizados para futuros trabajos con una mayor complejidad y número de enrutadores inalámbrico, así como establecer el grado de afectación y el comportamiento de las dos PBX cuando haya congestión en la red. |
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| Address | Escuela Superior Politécnica del Litoral Km 30.5 vía Perimetral | ||||
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| Publisher | Place of Publication | Guayaquil, Guayas Ecuador | Editor | ||
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Español | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 14 | ||
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| Author | Wilton Agila; Victor M. Huilcapi | ||||
| Title | Lógica borrosa para la estimación de estados críticos de una pila de combustible PEM | Type | Conference Article | ||
| Year | 2014 | Publication | Reconocimientos de Patrones, Control Inteligente y Comunicaciones (MACH 2014) | Abbreviated Journal | |
| Volume | 5 | Issue | Pages | ||
| Keywords | Caracterización de pilas de combustible PEM, estado de inundación y deshidratación de la membrana polimérica, árbol de decisión borroso, control, lógica difusa | ||||
| Abstract | La determinación en tiempo real de los estados críticos de operación de la pila de combustible de membrana intercambio protónico (siglas en ingles, PEM) es uno de los principales retos para los sistemas de control de pilas de combustible PEM. En este trabajo, se presenta el desarrollo e implementación de un método no invasivo de bajo coste basado en técnicas de decisión borrosa que permite estimar los estados críticos de operación de la pila de combustible PEM. La estimación se realiza mediante perturbaciones al estado de operación de la pila y el análisis posterior de la evolución temporal del voltaje generado por la pila. La implementación de esta técnica de estimulación-percepción de estado de la pila de combustible para la detección de estados críticos constituye una novedad y un paso hacia el control autónomo en óptimas condiciones de la operación de las pilas de combustible PEM. | ||||
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| Publisher | Universidad de Cuenca | Place of Publication | Editor | ||
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Español | Summary Language | Español | Original Title | |
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| Call Number | cidis @ cidis @ | Serial | 31 | ||
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| Author | Ortiz J.; Londono J.; Novillo F.; Ampuno A.; Chávez M. | ||||
| Title | Determinación de Invariantes en Grandes Centros de Datos basados en Topología Fat-Tree | Type | Journal Article | ||
| Year | 2015 | Publication | Revista Politécnica | Abbreviated Journal | |
| Volume | Vol. 35 | Issue | Pages | pp. 91-96 | |
| Keywords | Invariantes de red, topologías, Fat-tree, simulación, emulación | ||||
| Abstract | Durante los últimos años ha existido un fuerte incremento en el acceso a internet, causando que los centros de datos ( DC) deban adaptar dinámicamente su infraestructura de red de cara a enfrentar posibles problemas de congestión, la cual no siempre se da de forma oportuna. Ante esto, nuevas topologías de red se han propuesto en los últimos años, como una forma de brindar mejores condiciones para el manejo de tráfico interno, sin embargo es común que para el estudio de estas mejoras, se necesite recrear el comportamiento de un verdadero DC en modelos de simulación/emulación. Por lo tanto se vuelve esencial validar dichos modelos, de cara a obtener resultados coherentes con la realidad. Esta validación es posible por medio de la identificación de ciertas propiedades que se deducen a partir de las variables y los parámetros que describen la red, y que se mantienen en las topologías de los DC para diversos escenarios y/o configuraciones. Estas propiedades, conocidas como invariantes, son una expresión del funcionamiento de la red en ambientes reales, como por ejemplo la ruta más larga entre dos nodos o el número de enlaces mínimo que deben fallar antes de una pérdida de conectividad en alguno de los nodos de la red. En el presente trabajo se realiza la identificación, formulación y comprobación de dos invariantes para la topología Fat-Tree, utilizando como software emulador a mininet. Las conclusiones muestran resultados concordantes entre lo analítico y lo práctico. | ||||
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| Publisher | Escuela Politécnica Nacional | Place of Publication | Editor | ||
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Español | Summary Language | Español | Original Title | |
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| Notes | Approved | no | |||
| Call Number | cidis @ cidis @ | Serial | 32 | ||
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