168 research outputs found
Petri nets based components within globally asynchronous locally synchronous systems
Dissertação apresentada na Faculdade de Ciências e Tecnologias da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Electrotécnica e ComputadoresThe main goal is to develop a solution for the interconnection of components constituent of a GALS - Globally Asynchronous, Locally Synchronous – system. The components are implemented in parallel obtained as a result of the partition of a model expressed a Petri net (PN), performed using the PNs editor SNOOPY-IOPT in conjunction with the Split tool and the tools to automatically generate the VHDL code from the representations of the PNML models resulting from the partition (these tools were developed under the project FORDESIGN and are available at http://www.uninova.pt/FORDESIGN). Typical solutions will be analyzed to ensure proper communication between components of the GALS system, as well as characterized and developed an appropriate solution for the interconnection of the components associated with the PN sub-models. The final goal (not attained with this thesis) would be to acquire a tool that allows generation of code for the interconnection solution from the associated components, considering a specific application. The solution proposed for componentes interconnection was coded in VHDL and the implementation platforms used for testing include the Xilinx FPGA Spartan-3 and Virtex-II
Context aware advisor for public transportation
This paper presents an Android-based mobile app designed to provide real time context aware public transportation information and advice to its users through the combination of the user's preferences and geographic context with data retrieved from a public transportation information system called XTraN Passenger. Thus, this mobile app contributes to fulfill the necessities of the passengers, and also provides an incentive for people to use the public transportation infrastructure more frequently. The proposed mobile app allows the users to benefit from the access to real time public transportation data in a simple and intuitive way. The validation of the features and operation of the developed app was assessed with results from use cases and real-world experimental tests using public transportation data from a Brazilian bus fleet operator.This work is supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 –Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941
Batteries charging systems for electric and plug-in hybrid electric vehicles
Many countries have a large dependence on imported fossil fuels whose prices increase almost every day. Knowing that much of this consumption is for transportation systems, it becomes essential to seek for alternatives. The natural bet is the electric mobility, namely through Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs). However, the wide spread utilization of these vehicles has consequences on the electrical power grid, mainly in terms of load management and electric power quality, which are associated to the batteries charging systems. In this scenario, this chapter assesses the electric mobility integration in Smart Grid context, focusing different approaches to the operation of EVs and PHEVs charging processes and the specifications of the chargers, as well as different topologies of charging systems and their features, modes of operation, typical waveforms, and impact in the electrical power grid in terms of power quality. It is also presented a laboratory prototype of a bidirectional EV charger and shown some experimental results. This prototype was developed to charge the batteries aiming to preserve their lifespan, and to contribute to mitigate the degradation of the power quality. The experimental results show the operation of this prototype during the batteries charging process (G2V – Grid-to-Vehicle operation), and during the delivering of stored energy back to the electrical power grid (V2G – Vehicle-to-Grid operation).FEDER Funds - Operational Program for
Competitiveness Factors – COMPETEFundação para a Ciência e a Tecnologia (FCT) - FCOMP-01-0124-FEDER-022674, MITPT/
EDAM-SMS/0030/200
Bidirectional multilevel converter for electric vehicles
In this paper is presented an H-Bridge Multilevel Converter topology for Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs). The topology of the presented
multilevel converter allows the interface between the batteries, the electric motor of the vehicle, and the electrical power grid.
Thereby, taking into account that the proposed multilevel converter requires the use of isolated voltage sources, the
interface between the batteries and the multilevel converter is
evaluated regarding the converter operation as a Battery
Management System (BMS), controlling the charging and discharging processes. The interface between the multilevel converter and the electrical power grid is described considering a bidirectional operation. These modes of operation occur during
the batteries charging process, denominated as Grid-to-Vehicle
(G2V), and during the operation as Vehicle-to-Grid (V2G), that consists in delivering back to the electrical power grid a small amount of the energy stored in the batteries, in accordance with
the electrical grid requirements and with the vehicle driver accordance. In both modes of operation, the waveform of the AC current of the electrical power grid is kept sinusoidal with unitary power factor, contributing to maintain a good level of power quality.FEDER Funds - Operational Programme for Competitiveness Factors (COMPETE)Fundação para a Ciência e a Tecnologia (FCT) - PTDC/EEA-EEL/104569/2008, MITPT/
EDAM-SMS/0030/200
Assessment of a battery charger for electric vehicles with reactive power control
Batteries of Electric Vehicles (EVs) and Plug-in
Hybrid Electric Vehicles (PHEVs) have a large potential not
only to provide energy for the locomotion of these vehicles, but
also to interact, in dynamic way, with the power grid. Thereby,
through the energy stored in the batteries, these vehicles can be
used to regulate the active and the reactive power, as local
Energy Storage Systems. This way, EVs can contribute to help
the power grid to regulate the active and reactive power flow in
order to stabilize the production and consumption of energy.
For this propose should be defined usage profiles, controlled by
a collaborative broker, taking into account the requirements of
the power grid and the conveniences of the vehicle user. Besides,
the interface between the power grid and the EVs, instead of
using typical power converters that only work on unidirectional
mode, need to use bidirectional power converters to charge the
batteries (G2V - Grid-to-Vehicle mode) and to deliver part of
the stored energy in the batteries back to the power grid (V2G -
Vehicle-to-Grid mode). With the bidirectional power converter
topology presented in this paper, the consumed current is
sinusoidal and it is possible to regulate the power factor to
control the reactive power, aiming to contribute to mitigate
power quality problems in the power grid. To assess the
behavior of the presented bidirectional power converter under
different scenarios, are presented some computer simulations
and experimental results obtained with a prototype that was
developed to be integrated in an Electric Vehicle.Fundação para a Ciência e a Tecnologia (FCT) - FCOMP-01-0124-FEDER-022674, PTDC/EEAEEL/
104569/2008, MIT-PT/EDAM-SMS/0030/2008.FEDER Funds, through the
Operational Programme for Competitiveness Factors (COMPETE
ÉTICA NA ADMINISTRAÇÃO PÚBLICA E AS LÓGICAS DE MORALIDADES NA RELAÇÃO PÚBLICO-PRIVADO NO ESTADO-CIDADÃO
Este estudo pretende desenvolver a relevância da ética na administração pública brasileira como resposta aos desmandos com a coisa pública. Utilizar-se-á de pesquisa bibliográfica na compreensão dos principais conceitos e princípios ligados ao desenvolvimento da ética, bem como analisadas as interfaces das lógicas da moralidade existentes na relação público-privado. E como a corrupção endêmica no país interfere na qualidade de vida para as gerações do presente e do futuro, especialmente pela falta de oportunidade que permita a existência compatível com a dignidade humana. Conclui-se que o fortalecimento da ética que embasa o processo decisório por parte dos agentes da administração pública não pode se restringir às medidas coercitivas da Lei Penal e nem aos manuais de ética, mas precisa se pautar na transparência com o uso do dinheiro público, na excelência do serviço prestado pelo Estado-Cidadão
Prevalência de polimorfismos nos genes ANKK1, DRD2, DRD3 e síndrome metabólica na esquizofrenia refratária
Objetivo: estimar a prevalência dos polimorfismos TaqIA, -141C e rs6280 dos genes ANKK1, DRD2 e DRD3 e avaliar sua associação com a ocorrência de síndrome metabólica em pacientes com esquizofrenia refratária. Método: estudo de delineamento transversal, realizado na Região Ampliada Oeste de Minas Gerais, que incluiu pacientes com esquizofrenia refratária em uso do antipsicótico clozapina. Foram coletados dados sociodemográficos, clínicos, antropométricos, bioquímicos e genéticos. Realizou-se análise univariada dos dados. Resultados: participaram 72 pacientes e observou-se a ocorrência de Síndrome Metabólica em 47,2%, não sendo encontrada associação da Síndrome Metabólica com os polimorfismos estudados. Houve diferença estatisticamente significante com o parâmetro do baixo HDL com genótipo homozigoto para alelo C do polimorfismo -141C do gene DRD2. Conclusão: evidenciou-se prevalência de SM elevada. O polimorfismo -141C associou-se ao baixo HDL. A análise genética e a identificação de alterações metabólicas, neste grupo de pacientes, podem nortear o tratamento medicamentoso e propiciar melhor qualidade de vida.Objective: to estimate the prevalence of TaqIA, -141C and rs6280 polymorphisms of the ANKK1, DRD2 and DRD3 genes and evaluate their association with the occurrence of metabolic syndrome in patients with refractory schizophrenia. Method: cross-sectional study conducted in the Extended Western Region of Minas Gerais, with refractory schizophrenic patients using the antipsychotic clozapine. Sociodemographic, clinical, anthropometric, biochemical and genetic data were collected. Univariate analysis of the data was performed. Results: seventy-two patients participated in the study and the occurrence of Metabolic Syndrome was observed in 47.2% of them. There was no association between Metabolic Syndrome and the studied polymorphisms. There was a statistically significant difference in the low HDL parameter with homozygous genotype for the C allele of the -141C polymorphism of the DRD2 gene. Conclusion: a high prevalence of MS was evidenced. The -141C polymorphism was associated with low HDL. Genetic analysis and identification of metabolic alterations in this group of patients can guide drug treatment and provide a better quality of life.Objetivo: estimar la prevalencia de los polimorfismos TaqIA, -141C y rs6280 de los genes ANKK1, DRD2 y DRD3 y evaluar su asociación con el síndrome metabólico en pacientes con esquizofrenia refractária. Método: estudio de delineamiento transversal, realizado en la Región Ampliada Oeste de Minas Gerais, que incluye pacientes con esquizofrenia refractária usando el antipsicótico clozapina. Fueron recogidos datos sociodemográficos, clínicos, antropométricos, bioquímicos y genéticos. Se realizó um análisis univariada de los datos. Resultados: participaron 72 pacientes y se observó el Síndrome Metabólico en 47,2%, no siendo encontrada una asociación del Síndrome Metabólico con los polimorfismos estudiados. Hubo diferencia estadísticamente significante con el parámetro del bajo HDL con genotipo homozigoto para alelo C del polimorfismo -141C del gen DRD2. Conclusión: se vio una prevalencia de SM elevada. El polimorfismo -141C se asoció al bajo HDL. El análisis genético y la identificación de alteraciones metabólicas, en este grupo de pacientes, pueden guiar al tratamiento medicamentoso y propiciar mejor calidad de vida
Mitigating the susceptibility to intergranular corrosion of alloy 625 by friction‑stir welding
In this work, friction-stir welding (FSW) was employed to alloy 625 grade I (soft annealed) sheets. Therefore, solid-state based welding was undertaken with a tool rotational speed of 200 rpm and a welding speed of 1 mm/s. Microstructural features were analyzed by light optical and scanning electron microscopy (LOM and SEM). Moreover, microhardness measurements were performed. The susceptibility to intergranular corrosion was verifed by the double-loop electrochemical potentiokinetic reactivation (DL-EPR) test. Complementary, intergranular corrosion was also evaluated by the ASTM G28 Method A. FSW promoted grain refnement, increased microhardness, and reduction in the degree of sensitization. Finally, the mean corrosion rate observed in the ASTM G28 Method A test was 0.4406 mm/year, which suggests a good weld quality
- …