901 resultados para Many-core systems
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The Portuguese educational system has counted, for many years, with the co-existence of both public and private schools. In fact, the country’s growth and development led, in the past, to an increasing demand for free of charge public education that could only be matched through the creation of “publicly-subsidized and privately owned and managed schools”. Still, the demographic evolution of Portugal recently generated a decrease on the demand for public educational services. This situation has raised doubts about the true contribution of this type of school for the public education system. This paper aims at answering this question by isolating the impact of different property and management schemes on the performance of students, resorting to cross-section data on 9th grade students from 2010. The results corroborate the well known result on the relevance of the family socio-economic background for students’ performance, but do also sustain the existence of a significant positive impact of private ownership and management schemes on the overall performance of students. These results suggest that there might be gains associated with the expansion of such schemes within the public education system.
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Nowadays, many of the manufactory and industrial system has a diagnosis system on top of it, responsible for ensuring the lifetime of the system itself. It achieves this by performing both diagnosis and error recovery procedures in real production time, on each of the individual parts of the system. There are many paradigms currently being used for diagnosis. However, they still fail to answer all the requirements imposed by the enterprises making it necessary for a different approach to take place. This happens mostly on the error recovery paradigms since the great diversity that is nowadays present in the industrial environment makes it highly unlikely for every single error to be fixed under a real time, no production stop, perspective. This work proposes a still relatively unknown paradigm to manufactory. The Artificial Immune Systems (AIS), which relies on bio-inspired algorithms, comes as a valid alternative to the ones currently being used. The proposed work is a multi-agent architecture that establishes the Artificial Immune Systems, based on bio-inspired algorithms. The main goal of this architecture is to solve for a resolution to the error currently detected by the system. The proposed architecture was tested using two different simulation environment, each meant to prove different points of views, using different tests. These tests will determine if, as the research suggests, this paradigm is a promising alternative for the industrial environment. It will also define what should be done to improve the current architecture and if it should be applied in a decentralised system.
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Hand gestures are a powerful way for human communication, with lots of potential applications in the area of human computer interaction. Vision-based hand gesture recognition techniques have many proven advantages compared with traditional devices, giving users a simpler and more natural way to communicate with electronic devices. This work proposes a generic system architecture based in computer vision and machine learning, able to be used with any interface for human-computer interaction. The proposed solution is mainly composed of three modules: a pre-processing and hand segmentation module, a static gesture interface module and a dynamic gesture interface module. The experiments showed that the core of visionbased interaction systems could be the same for all applications and thus facilitate the implementation. For hand posture recognition, a SVM (Support Vector Machine) model was trained and used, able to achieve a final accuracy of 99.4%. For dynamic gestures, an HMM (Hidden Markov Model) model was trained for each gesture that the system could recognize with a final average accuracy of 93.7%. The proposed solution as the advantage of being generic enough with the trained models able to work in real-time, allowing its application in a wide range of human-machine applications. To validate the proposed framework two applications were implemented. The first one is a real-time system able to interpret the Portuguese Sign Language. The second one is an online system able to help a robotic soccer game referee judge a game in real time.
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Hand gestures are a powerful way for human communication, with lots of potential applications in the area of human computer interaction. Vision-based hand gesture recognition techniques have many proven advantages compared with traditional devices, giving users a simpler and more natural way to communicate with electronic devices. This work proposes a generic system architecture based in computer vision and machine learning, able to be used with any interface for humancomputer interaction. The proposed solution is mainly composed of three modules: a pre-processing and hand segmentation module, a static gesture interface module and a dynamic gesture interface module. The experiments showed that the core of vision-based interaction systems can be the same for all applications and thus facilitate the implementation. In order to test the proposed solutions, three prototypes were implemented. For hand posture recognition, a SVM model was trained and used, able to achieve a final accuracy of 99.4%. For dynamic gestures, an HMM model was trained for each gesture that the system could recognize with a final average accuracy of 93.7%. The proposed solution as the advantage of being generic enough with the trained models able to work in real-time, allowing its application in a wide range of human-machine applications.
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The MAP-i doctoral program of the Universities of Minho, Aveiro and Porto
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During the last few years many research efforts have been done to improve the design of ETL (Extract-Transform-Load) systems. ETL systems are considered very time-consuming, error-prone and complex involving several participants from different knowledge domains. ETL processes are one of the most important components of a data warehousing system that are strongly influenced by the complexity of business requirements, their changing and evolution. These aspects influence not only the structure of a data warehouse but also the structures of the data sources involved with. To minimize the negative impact of such variables, we propose the use of ETL patterns to build specific ETL packages. In this paper, we formalize this approach using BPMN (Business Process Modelling Language) for modelling more conceptual ETL workflows, mapping them to real execution primitives through the use of a domain-specific language that allows for the generation of specific instances that can be executed in an ETL commercial tool.
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Increasing the maturity in Project Management (PM) has become a goal for many organizations, leading them to adopt maturity models to assess the current state of its PM practices and compare them with the best practices in the industry where the organization is inserted. One of the main PM maturity models is the Organizational Project Management Maturity Model (OPM3®), developed by the Project Management Institute. This paper presents the Information Systems and Technologies organizations outcome analysis, of the assesses made by the OPM3® Portugal Project, identifying the PM processes that are “best” implemented in this particular industry and those in which it is urgent to improve. Additionally, a comparison between the different organizations’ size analyzed is presented.
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Tese de Doutoramento em Engenharia de Eletrónica e de Computadores
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Programa Doutoral em Engenharia Biomédica
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IDENTIFICACIÓN DEL PROBLEMA DE ESTUDIO. Las sustancias orgánicas solubles en agua no biodegradables tales como ciertos herbicidas, colorantes industriales y metabolitos de fármacos de uso masivo son una de las principales fuentes de contaminación en aguas subterráneas de zonas agrícolas y en efluentes industriales y domésticos. Las reacciones fotocatalizadas por irradiación UV-visible y sensitizadores orgánicos e inorgánicos son uno de los métodos más económicos y convenientes para la descomposición de contaminantes en subproductos inocuos y/o biodegradables. En muchas aplicaciones es deseable un alto grado de especificidad, efectividad y velocidad de degradación de un dado agente contaminante que se encuentra presente en una mezcla compleja de sustancias orgánicas en solución. En particular son altamente deseables sistemas nano/micro -particulados que formen suspensiones acuosas estables debido a que estas permiten una fácil aplicación y una eficaz acción descontaminante en grandes volúmenes de fluidos. HIPÓTESIS Y PLANTEO DE LOS OBJETIVOS. El objetivo general de este proyecto es desarrollar sistemas nano/micro particulados formados por polímeros de impresión molecular (PIMs) y foto-sensibilizadores (FS). Un PIMs es un polímero especialmente sintetizado para que sea capaz de reconocer específicamente un analito (molécula plantilla) determinado. La actividad de unión específica de los PIMs en conjunto con la capacidad fotocatalizadora de los sensibilizadores pueden ser usadas para lograr la fotodescomposición específica de moléculas “plantilla” (en este caso un dado contaminante) en soluciones conteniendo mezclas complejas de sustancias orgánicas. MATERIALES Y MÉTODOS A UTILIZAR. Se utilizaran técnicas de polimerización en mini-emulsión para sintetizar los sistemas nano/micro PIM-FS para buscar la degradación de ciertos compuestos de interés. Para caracterizar eficiencias, mecanismos y especificidad de foto-degradación en dichos sistemas se utilizan diversas técnicas espectroscópicas (estacionarias y resueltas en el tiempo) y de cromatografía (HPLC y GC). Así mismo, para medir directamente distribuciones de afinidades de unión y eficiencia de foto-degradación se utilizaran técnicas de fluorescencia de molécula/partícula individual. Estas determinaciones permitirán obtener resultados importantes al momento de analizar los factores que afectan la eficiencia de foto-degradación (nano/micro escala), tales como cantidad y ubicación de foto- sensibilizadores en las matrices poliméricas y eficiencia de unión de la plantilla y los productos de degradación al PIM. RESULTADOS ESPERADOS. Los estudios propuestos apuntan a un mejor entendimiento de procesos foto-iniciados en entornos nano/micro-particulados para aplicar dichos conocimientos al diseño de sistemas optimizados para la foto-destrucción selectiva de contaminantes acuosos de relevancia social; tales como herbicidas, residuos industriales, metabolitos de fármacos de uso masivo, etc. IMPORTANCIA DEL PROYECTO. Los sistemas nano/micro-particulados PIM-FS que se propone desarrollar en este proyecto se presentan como candidatos ideales para tratamientos específicos de efluentes industriales y domésticos en los cuales se desea lograr la degradación selectiva de compuestos orgánicos. Los conocimientos adquiridos serán indispensables para construir una plataforma versátil de sistemas foto-catalíticos específicos para la degradación de diversos contaminantes orgánicos de interés social. En lo referente a la formación de recursos humanos, el proyecto propuesto contribuirá en forma directa a la formación de 3 estudiantes de postgrado y 2 estudiantes de grado. En las capacidades institucionales se contribuirá al acondicionamiento del Laboratorio para Microscopía Óptica Avanzada (LMOA) en el Dpto. de Química de la UNRC y al montaje de un sistema de microscopio de fluorescencia que permitirá la aplicación de técnicas avanzadas de espectroscopia de fluorescencia de molecula individual. Water-soluble organic molecules such as certain non-biodegradable herbicides, industrial dyes and metabolites of widespread use drugs are a major source of pollution in groundwater from agricultural areas and in industrial and domestic effluents. Photo-catalytic reactions by UV-visible irradiation and organic sensitizers are one of the most economical and convenient methods for the decomposition of pollutants into harmless byproducts. In many applications it is highly desirable a high degree of specificity, effectiveness and speed of degradation of specific pollutants present in a complex mixture. In particular nano/micro-particles systems that form stable aqueous suspensions are highly desirable because they allow for easy application and effective decontamination of large volumes of fluids. Herein we propose the development of nano/micro particles composed by molecularly imprinted polymers (MIP) and photo-sensitizers (PS). The specific binding of MIP and the photo-catalytic ability of the sensitizers are used to achieve the photo-decomposition of specific "template" molecules in complex mixtures. Mini-emulsion polymerization techniques will be used to synthesize nano/micro MIP-FS systems. Spectroscopy (steady-state and time resolved) and chromatography (GC and HPLC) will be used to characterize efficiency, mechanisms and specificity of photo-degradation in these systems. In addition single molecule/particle fluorescence spectroscopy techniques will be used to directly measure distributions of binding affinities and photo-degradation efficiency in individual particles. The proposed studies point to a more detailed understanding of the factors affecting the photo-degradation efficiency in nano/micro-particles and to apply that knowledge in the design of optimized systems for photo-selective destruction of socially relevant aqueous pollutants.
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Recent studies have shown that septic tank systems are a major source of groundwater pollution. Many public health workers feel that the most cri^cal aspect of the use of septic tanks as a means of sewage disposal is the contamination of private water wells with attendant human health hazards. In this study the movement and attenuation of septic tank effluents in a range of soil/overburden types and hydrogeological situations was investigated. The suitability of a number of chemical and biological tracer materials to monitor the movement of septic tank effluent constituents to groundwater sources was also examined. The investigation was divided into three separate but inteiTelated sections. In the first section of the study the movement of septic tank effluent from two soil treatment systems was investigated by direct measurements of soil nutrient concentrations and enteric bacterial numbers in the soil beneath and downgradient of the test systems. Two sites with different soil types and hydrogeological characteristics were used. The results indicated that the attenuation of the effluent in both of the treatment systems was incomplete. Migration of nitrate, ammonium, phosphate and fecal bacteria to a depth of 50 cm beneath the inverts of the distribution tiles was demonstrated on all sampling occasions. The lateral migration of the pollutants was less pronounced, although on occasions high nutrients levels and fecal bacterial numbers were detected at a lateral distance of 4.0 m downgradient of the test systems. There was evidence that the degree and extent of effluent migration was increased after periods of heavy or prolonged rainfall when the attenuating properties of the treatment systems were reduced as a result of saturation of the soil. The second part of the study examined the contamination of groundwaters downgradient of septic tank soil treatment systems. Three test sites were used in the investigation. The sites were chosen because of differences in the thicknesses and nature of the unsaturated zone available for effluent attenuation at each of the locations. A series of groundwater monitoring boreholes were installed downgradient of the test systems at each of the sites and these were sampled regularly to assess the efficiency of the overburden material in reducing the polluting potential of the wastewater. Effluent attenuation in the septic tank treatment systems was shown to be incomplete, resulting in chemical and microbiological contamination of the groundwaters downgradient of the systems. The nature and severity of groundwater contamination was dependent on the composition and thickness of the unsaturated zone and the extent of weathering in the underlying saturated bedrock. The movement of septic tank effluent through soil/overburdens to groundwater sources was investigated by adding a range of chemical and biological tracer materials to the three septic tank systems used in section two of the study. The results demonstrated that a single tracer type cannot be used to accurately monitor the movement of all effluent constituents through soils to groundwater. The combined use of lithium bromide and endospores of Bacillus globigii was found to give an accurate indication of the movement of both the chemical and biological effluent constituents.
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This is a study of a state of the art implementation of a new computer integrated testing (CIT) facility within a company that designs and manufactures transport refrigeration systems. The aim was to use state of the art hardware, software and planning procedures in the design and implementation of three CIT systems. Typical CIT system components include data acquisition (DAQ) equipment, application and analysis software, communication devices, computer-based instrumentation and computer technology. It is shown that the introduction of computer technology into the area of testing can have a major effect on such issues as efficiency, flexibility, data accuracy, test quality, data integrity and much more. Findings reaffirm how the overall area of computer integration continues to benefit any organisation, but with more recent advances in computer technology, communication methods and software capabilities, less expensive more sophisticated test solutions are now possible. This allows more organisations to benefit from the many advantages associated with CIT. Examples of computer integration test set-ups and the benefits associated with computer integration have been discussed.
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Multi-core processors is a design philosophy that has become mainstream in scientific and engineering applications. Increasing performance and gate capacity of recent FPGA devices has permitted complex logic systems to be implemented on a single programmable device. By using VHDL here we present an implementation of one multi-core processor by using the PLASMA IP core based on the (most) MIPS I ISA and give an overview of the processor architecture and share theexecution results.
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Thermal systems interchanging heat and mass by conduction, convection, radiation (solar and thermal ) occur in many engineering applications like energy storage by solar collectors, window glazing in buildings, refrigeration of plastic moulds, air handling units etc. Often these thermal systems are composed of various elements for example a building with wall, windows, rooms, etc. It would be of particular interest to have a modular thermal system which is formed by connecting different modules for the elements, flexibility to use and change models for individual elements, add or remove elements without changing the entire code. A numerical approach to handle the heat transfer and fluid flow in such systems helps in saving the full scale experiment time, cost and also aids optimisation of parameters of the system. In subsequent sections are presented a short summary of the work done until now on the orientation of the thesis in the field of numerical methods for heat transfer and fluid flow applications, the work in process and the future work.
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Due to the eye's specific anatomical and physiological conformation, the treatment of eye diseases is a real challenge for pharmaceutical therapy. The presence of efficient protective barriers (i.e., the conjunctival and corneal membranes) and protective mechanisms (i.e., blinking and nasolachrymal drainage) makes this organ particularly impervious to local drug therapy. To overcome these issues, numerous strategies have been envisioned using pharmaceutical technology. Many formulations currently on the market or still under development are emulsions or colloidal systems intended to enhance precorneal residence time and corneal penetration, causing a consequent increase in drug bioavailability after instillation. After a review of some recent developments in the field of cyclosporin A formulations for the eye, a novel micellar formulation of cyclosporine A based on a diblock methoxy-poly(ethylene glycol)-hexysubstituted poly(lactides) (MPEG-hexPLA) is described.