905 resultados para Circuitos
Resumo:
The real-time embedded systems design requires precise control of the passage of time in the computation performed by the modules and communication between them. Generally, these systems consist of several modules, each designed for a specific task and restricted communication with other modules in order to obtain the required timing. This strategy, called federated architecture, is already becoming unviable in front of the current demands of cost, required performance and quality of embedded system. To address this problem, it has been proposed the use of integrated architectures that consist of one or few circuits performing multiple tasks in parallel in a more efficient manner and with reduced costs. However, one has to ensure that the integrated architecture has temporal composability, ie the ability to design each task temporally isolated from the others in order to maintain the individual characteristics of each task. The Precision Timed Machines are an integrated architecture approach that makes use of multithreaded processors to ensure temporal composability. Thus, this work presents the implementation of a Precision Machine Timed named Hivek-RT. This processor which is a VLIW supporting Simultaneous Multithreading is capable of efficiently execute real-time tasks when compared to a traditional processor. In addition to the efficient implementation, the proposed architecture facilitates the implementation real-time tasks from a programming point of view.
Resumo:
The Artificial Neural Networks (ANN), which is one of the branches of Artificial Intelligence (AI), are being employed as a solution to many complex problems existing in several areas. To solve these problems, it is essential that its implementation is done in hardware. Among the strategies to be adopted and met during the design phase and implementation of RNAs in hardware, connections between neurons are the ones that need more attention. Recently, are RNAs implemented both in application specific integrated circuits's (Application Specific Integrated Circuits - ASIC) and in integrated circuits configured by the user, like the Field Programmable Gate Array (FPGA), which have the ability to be partially rewritten, at runtime, forming thus a system Partially Reconfigurable (SPR), the use of which provides several advantages, such as flexibility in implementation and cost reduction. It has been noted a considerable increase in the use of FPGAs for implementing ANNs. Given the above, it is proposed to implement an array of reconfigurable neurons for topologies Description of artificial neural network multilayer perceptrons (MLPs) in FPGA, in order to encourage feedback and reuse of neural processors (perceptrons) used in the same area of the circuit. It is further proposed, a communication network capable of performing the reuse of artificial neurons. The architecture of the proposed system will configure various topologies MLPs networks through partial reconfiguration of the FPGA. To allow this flexibility RNAs settings, a set of digital components (datapath), and a controller were developed to execute instructions that define each topology for MLP neural network.
Resumo:
The Artificial Neural Networks (ANN), which is one of the branches of Artificial Intelligence (AI), are being employed as a solution to many complex problems existing in several areas. To solve these problems, it is essential that its implementation is done in hardware. Among the strategies to be adopted and met during the design phase and implementation of RNAs in hardware, connections between neurons are the ones that need more attention. Recently, are RNAs implemented both in application specific integrated circuits's (Application Specific Integrated Circuits - ASIC) and in integrated circuits configured by the user, like the Field Programmable Gate Array (FPGA), which have the ability to be partially rewritten, at runtime, forming thus a system Partially Reconfigurable (SPR), the use of which provides several advantages, such as flexibility in implementation and cost reduction. It has been noted a considerable increase in the use of FPGAs for implementing ANNs. Given the above, it is proposed to implement an array of reconfigurable neurons for topologies Description of artificial neural network multilayer perceptrons (MLPs) in FPGA, in order to encourage feedback and reuse of neural processors (perceptrons) used in the same area of the circuit. It is further proposed, a communication network capable of performing the reuse of artificial neurons. The architecture of the proposed system will configure various topologies MLPs networks through partial reconfiguration of the FPGA. To allow this flexibility RNAs settings, a set of digital components (datapath), and a controller were developed to execute instructions that define each topology for MLP neural network.
Resumo:
This thesis presents a hybrid technique of frequency selective surfaces project (FSS) on a isotropic dielectric layer, considering various geometries for the elements of the unit cell. Specifically, the hybrid technique uses the equivalent circuit method in conjunction with genetic algorithm, aiming at the synthesis of structures with response single-band and dual-band. The equivalent circuit method allows you to model the structure by using an equivalent circuit and also obtaining circuits for different geometries. From the obtaining of the parameters of these circuits, you can get the transmission and reflection characteristics of patterned structures. For the optimization of patterned structures, according to the desired frequency response, Matlab™ optimization tool named optimtool proved to be easy to use, allowing you to explore important results on the optimization analysis. In this thesis, numeric and experimental results are presented for the different characteristics of the analyzed geometries. For this, it was determined a technique to obtain the parameter N, which is based on genetic algorithms and differential geometry, to obtain the algebraic rational models that determine values of N more accurate, facilitating new projects of FSS with these geometries. The optimal results of N are grouped according to the occupancy factor of the cell and the thickness of the dielectric, for modeling of the structures by means of rational algebraic equations. Furthermore, for the proposed hybrid model was developed a fitness function for the purpose of calculating the error occurred in the definitions of FSS bandwidths with transmission features single band and dual band. This thesis deals with the construction of prototypes of FSS with frequency settings and band widths obtained with the use of this function. The FSS were initially reviewed through simulations performed with the commercial software Ansoft Designer ™, followed by simulation with the equivalent circuit method for obtaining a value of N in order to converge the resonance frequency and the bandwidth of the FSS analyzed, then the results obtained were compared. The methodology applied is validated with the construction and measurement of prototypes with different geometries of the cells of the arrays of FSS.
Resumo:
This thesis presents a hybrid technique of frequency selective surfaces project (FSS) on a isotropic dielectric layer, considering various geometries for the elements of the unit cell. Specifically, the hybrid technique uses the equivalent circuit method in conjunction with genetic algorithm, aiming at the synthesis of structures with response single-band and dual-band. The equivalent circuit method allows you to model the structure by using an equivalent circuit and also obtaining circuits for different geometries. From the obtaining of the parameters of these circuits, you can get the transmission and reflection characteristics of patterned structures. For the optimization of patterned structures, according to the desired frequency response, Matlab™ optimization tool named optimtool proved to be easy to use, allowing you to explore important results on the optimization analysis. In this thesis, numeric and experimental results are presented for the different characteristics of the analyzed geometries. For this, it was determined a technique to obtain the parameter N, which is based on genetic algorithms and differential geometry, to obtain the algebraic rational models that determine values of N more accurate, facilitating new projects of FSS with these geometries. The optimal results of N are grouped according to the occupancy factor of the cell and the thickness of the dielectric, for modeling of the structures by means of rational algebraic equations. Furthermore, for the proposed hybrid model was developed a fitness function for the purpose of calculating the error occurred in the definitions of FSS bandwidths with transmission features single band and dual band. This thesis deals with the construction of prototypes of FSS with frequency settings and band widths obtained with the use of this function. The FSS were initially reviewed through simulations performed with the commercial software Ansoft Designer ™, followed by simulation with the equivalent circuit method for obtaining a value of N in order to converge the resonance frequency and the bandwidth of the FSS analyzed, then the results obtained were compared. The methodology applied is validated with the construction and measurement of prototypes with different geometries of the cells of the arrays of FSS.
Resumo:
The search for mitigation solutions, with respect to the effects of overvoltages linked to the energization and reclosing maneuvers of transmission lines include a challenging subject with strong impact on the insulation coordination of electrical systems. Although the recognition of classical and commercial proposals to mitigate these phenomena, other possibilities are certainly still worthwhile highlighting and investigations. In this context, the present work is grounded in the exposure of the physical and mathematical foundations of a strategy based on controlled switchings, whose moments to the line reclosing are pre-programmed. The computational evaluation of the effectiveness of the methodology is made using the ATP simulator, which are studies in a typical electrical system subjected to the action of short-circuits fallowed by shutdowns and subsequent reclosing, under the action of technology here focused and lack thereof.
Resumo:
En el mundo de la simulación existen varios tipos de sistemas reales, entre los que se encuentran los sistemas de eventos discretos. Para poder simular estos sistemas se pueden utilizar, entre otras, herramientas basadas en el formalismo DEVS (Discrete EVents system Specification), como la utilizada en este proyecto: xDEVS. La simulación posee una importancia muy elevada en campos como la educación y la ciencia, y en ocasiones es necesario incluir datos del medio físico o sacar información al exterior del simulador. Por ello es necesario contar con herramientas que puedan realizar simulaciones utilizando sensores, actuadores, circuitos externos, etc., o lo que es lo mismo, que puedan realizar co-simulaciones entre software y hardware. De esta forma se puede facilitar el desarrollo de sistemas por medio de modelado y simulación, pudiendo extraer el hardware gradualmente y analizar los resultados en cada etapa. Este proyecto es de carácter incremental, y trata de extender la funcionalidad de la plataforma xDEVS para poder realizar co-simulaciones entre hardware y software sobre una Raspberry Pi. Para ello se van a utilizar circuitos lógicos como hardware externo y se enlazarán al simulador a través de ficheros de dispositivo, gestionados por módulos del kernel de Linux. Como caso de estudio se desarrolla la co-simulación entre hardware y software completa de un ascensor de siete plantas para mostrar el uso y funcionamiento en xDEVS, extrayendo los circuitos integrados de uno en uno.
Resumo:
Faced with an agribusiness expansion scenario and the increase in fertilizer consumption due to the exponential growth of the population, it is necessary to make better use of existing reserves, by obtaining products of better quality and in adequate quantities to meet demand national. In Tapira Mining Complex, Vale Fertilizantes, the phosphate concentrate is produced with content of 35.0% P2O5 from ore with content of about 8.0% P2O5, which are intended to supply Complex Industrial Uberaba and Araxá Minero Chemical Complex for the production of fertilizers. The industrial flotation step responsible for the recovery of P2O5 and hence the viability of the business is divided into the crumbly, grainy and ultrathin circuits, and, friable and granular concentrate comprise the conventional concentrated. Today only 14.7% of the mass which feeds the mill product becomes, the remainder being considered losses in the process, and the larger mass losses are located in the waste of flotation, representing 42.3%. From 2012 to 2014, the daily global mass recovery processing plants varied from 12.4 to 15.9% while the daily metallurgical recovery of P2O5 from 48.7 to 82.4%. By the degree of variability, it appears that the plant operated under different conditions. Seen this, this study aimed to analyze the influence of operational and process variables in P2O5 mass and metallurgical recoveries of industrial flotation circuits of grainy, crumbly and ultrathin. And besides was made an analysis of the effect of ore variables, as degrees, hardnesse and the ore front 02 percentage, in global recoveries of processing plant and the effect of dosages of reagents in the recoveries obtained from the bench flotation using the experimental design methodology. All work was performed using the historical database of Vale Fertilizantes of Tapira-MG, where all independent variables were dimensionless as the experimental range used. To make the statistical analysis it used the response surface technique and the values of the independent variables that maximize recoveries were found by canonical analysis. In the study of industrial flotation circuit crispy were obtained from 41.3% mass recovery and 91.3% metallurgical recovery P2O5, good values for the circuit, and the highest recoveries occur for solids concentration of the new flotation power between 45 and 50%, which values are assigned to the residence time of the pulp in cells and industrial flotation columns. The greater the number of ore heaps resumed on the higher the mass recovery, but in this scenario flotation becomes unstable because there is enormous weight variation in the feed. Higher recoveries are obtained for mass depressant dosage exceeding 120 g / t for synthetic collector dosage of 11.6%. In the study of industrial flotation circuit of the granulate were obtained 28.3% to 79.4% mass recovery and metallurgical recovery of P2O5 being considered good values for the circuit. Higher recoveries are obtained when the front ore 02 percentage is above 90%, because the ore of this front have more clear apatite. Likewise recoveries increase when the level of pulp rougher step is highest due to the high mass of circulating step receives loads. In the analysis of industrial flotation circuit of the ultrafine were obtained 23.95% of mass recovery, and the same is maximized to depressant dosage and the top collector 420 and 300 g / t, respectively. The analysis of the influence of variables ore, it was observed that higher recoveries are obtained for ores with P2O5 content above 8.0%, Fe2O3 content in the order of 28% forward and 02 of ore percentage of 83%. Hard ore percentage has strong influence on recoveries due to mass division in the circuit that is linked to this variable. However, the hard ore percentage that maximizes recoveries was very close to the design capacity of the processing plant, which is 20%. Finally, the study of the bench flotation, has noted that in friable and granular circuits the highest recoveries are achieved for a collector dosage exceeding 250 g / t and the simultaneous increase of collector dosage and synthetic collector percentage contributes to the increase recovery in the flotation, but this scenario is suitable to produce a concentrate poorer in terms of P2O5 content, showing that higher recovery is not always the ideal scenario. Thus, the results show the values of variables that provide higher recoveries in the flotation and hence lower losses in the waste.
Resumo:
La ponencia presenta los resultados de la tesis de maestría denominada "Las elecciones de los docentes de Educación Física de escuela secundaria frente a la oferta de capacitación, en La Plata (2007 - 2009)", cuyo objetivo fue analizar la elección de la capacitación desde la perspectiva de los actores, considerando la incidencia de sus contextos y la interacción con las culturas escolares en la que conviven. El enfoque conceptual- metodológico se enmarcó en la perspectiva del saber docente y su desarrollo profesional, en interacción con las características de las políticas de formación docente continua. En función de ello, se realizaron entrevistas a docentes de Educación Física, a responsables de la gestión de acciones de capacitación en el distrito de La Plata, y se analizaron los documentos que regulan la capacitación en la provincia de Buenos Aires. La ponencia explica las estrategias de elección de la capacitación de los docentes de Educación Física, a través de las siguientes dimensiones de análisis: I) qué demuestran las políticas de capacitación en clave histórica; II) la valorización del saber docente en las políticas de capacitación; III) el triunfo de la lógica del puntaje sobre la lógica de la acreditación; IV) la capacitación y las particularidades del saber en Educación Física, V) los formatos, los circuitos y los destinatarios de la capacitación
Resumo:
El propósito de este trabajo de investigación es relevar la experiencia de una escuela pública del distrito de La Matanza, en el conurbano bonaerense. Esta institución enclavada en una zona popular, Villa Scasso, fue creada hace trece años y atiende a una población infantil y juvenil de educación especial. El motivo de la investigación no se centra en la especificidad de este campo educativo sino en el proceso de construcción de una propuesta pedagógica que tensiona las formas escolares, amplía las fronteras educativas y transforma el tiempo y el espacio escolar. La atención de la presente indagación está puesta en problematizar la relación de la educación con la desigualdad y la igualdad, con el objetivo de abrir nuevos interrogantes sobre el carácter de determinación que se le otorga a la pobreza, la marginalidad y la exclusión en el terreno educativo, en particular en su relación con las escuelas de sectores populares. Las infancias populares acceden a circuitos de escolarización diferenciados, pero su carácter reproductor y/o emancipador configura un discurso que no se clausura a priori. Esta tesis doctoral abre interrogantes sobre esta problemática y documenta una experiencia educativa que "hace escuela" de manera "especial"
Resumo:
La cuestión de la "dependencia intelectual" es una de las preocupaciones más antiguas y sistemáticas del pensamiento latinoamericano. En este trabajo observamos cuáles han sido los cambios recientes en las formas de producción intelectual y su circulación que atraviesan los espacios nacionales, segmentando los procesos de consagración. Argumentamos que la colonialidad intelectual no describe la actual situación de nuestros campos académicos, más bien caracterizados por la convivencia conflictiva de la autonomía y la heteronomía. La dependencia académica, sin embargo, existe, pero es necesario observarla y analizarla como "situación concreta" llevando a fondo el enfoque relacional de la tradición histórico-estructural latinoamericana. En esta línea, primero analizamos el itinerario latinoamericano del debate sobre la dependencia intelectual, para luego proponer una definición operativa de dependencia académica. Finalmente, desarrollamos nuestra propuesta analítica para observar la producción de conocimientos en la periferia a partir de la articulación del concepto de "campo" y de "circuito".
Resumo:
El propósito de este trabajo de investigación es relevar la experiencia de una escuela pública del distrito de La Matanza, en el conurbano bonaerense. Esta institución enclavada en una zona popular, Villa Scasso, fue creada hace trece años y atiende a una población infantil y juvenil de educación especial. El motivo de la investigación no se centra en la especificidad de este campo educativo sino en el proceso de construcción de una propuesta pedagógica que tensiona las formas escolares, amplía las fronteras educativas y transforma el tiempo y el espacio escolar. La atención de la presente indagación está puesta en problematizar la relación de la educación con la desigualdad y la igualdad, con el objetivo de abrir nuevos interrogantes sobre el carácter de determinación que se le otorga a la pobreza, la marginalidad y la exclusión en el terreno educativo, en particular en su relación con las escuelas de sectores populares. Las infancias populares acceden a circuitos de escolarización diferenciados, pero su carácter reproductor y/o emancipador configura un discurso que no se clausura a priori. Esta tesis doctoral abre interrogantes sobre esta problemática y documenta una experiencia educativa que "hace escuela" de manera "especial"
Resumo:
La ponencia presenta los resultados de la tesis de maestría denominada "Las elecciones de los docentes de Educación Física de escuela secundaria frente a la oferta de capacitación, en La Plata (2007 - 2009)", cuyo objetivo fue analizar la elección de la capacitación desde la perspectiva de los actores, considerando la incidencia de sus contextos y la interacción con las culturas escolares en la que conviven. El enfoque conceptual- metodológico se enmarcó en la perspectiva del saber docente y su desarrollo profesional, en interacción con las características de las políticas de formación docente continua. En función de ello, se realizaron entrevistas a docentes de Educación Física, a responsables de la gestión de acciones de capacitación en el distrito de La Plata, y se analizaron los documentos que regulan la capacitación en la provincia de Buenos Aires. La ponencia explica las estrategias de elección de la capacitación de los docentes de Educación Física, a través de las siguientes dimensiones de análisis: I) qué demuestran las políticas de capacitación en clave histórica; II) la valorización del saber docente en las políticas de capacitación; III) el triunfo de la lógica del puntaje sobre la lógica de la acreditación; IV) la capacitación y las particularidades del saber en Educación Física, V) los formatos, los circuitos y los destinatarios de la capacitación
Resumo:
La ponencia presenta los resultados de la tesis de maestría denominada "Las elecciones de los docentes de Educación Física de escuela secundaria frente a la oferta de capacitación, en La Plata (2007 - 2009)", cuyo objetivo fue analizar la elección de la capacitación desde la perspectiva de los actores, considerando la incidencia de sus contextos y la interacción con las culturas escolares en la que conviven. El enfoque conceptual- metodológico se enmarcó en la perspectiva del saber docente y su desarrollo profesional, en interacción con las características de las políticas de formación docente continua. En función de ello, se realizaron entrevistas a docentes de Educación Física, a responsables de la gestión de acciones de capacitación en el distrito de La Plata, y se analizaron los documentos que regulan la capacitación en la provincia de Buenos Aires. La ponencia explica las estrategias de elección de la capacitación de los docentes de Educación Física, a través de las siguientes dimensiones de análisis: I) qué demuestran las políticas de capacitación en clave histórica; II) la valorización del saber docente en las políticas de capacitación; III) el triunfo de la lógica del puntaje sobre la lógica de la acreditación; IV) la capacitación y las particularidades del saber en Educación Física, V) los formatos, los circuitos y los destinatarios de la capacitación
Resumo:
El propósito de este trabajo de investigación es relevar la experiencia de una escuela pública del distrito de La Matanza, en el conurbano bonaerense. Esta institución enclavada en una zona popular, Villa Scasso, fue creada hace trece años y atiende a una población infantil y juvenil de educación especial. El motivo de la investigación no se centra en la especificidad de este campo educativo sino en el proceso de construcción de una propuesta pedagógica que tensiona las formas escolares, amplía las fronteras educativas y transforma el tiempo y el espacio escolar. La atención de la presente indagación está puesta en problematizar la relación de la educación con la desigualdad y la igualdad, con el objetivo de abrir nuevos interrogantes sobre el carácter de determinación que se le otorga a la pobreza, la marginalidad y la exclusión en el terreno educativo, en particular en su relación con las escuelas de sectores populares. Las infancias populares acceden a circuitos de escolarización diferenciados, pero su carácter reproductor y/o emancipador configura un discurso que no se clausura a priori. Esta tesis doctoral abre interrogantes sobre esta problemática y documenta una experiencia educativa que "hace escuela" de manera "especial"