1000 resultados para Modelo de control


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A Center for Weather Forecast and Climatic Studies of National Institute for Space Research (CPTEC/INPE) has provided to the Brazilian Geodetic community, since 2004, an alternative to correct the GNSS observables from the tropospheric refraction. Numerical Weather Prediction (NWP) Model is used to generate Zenital Tropospheric Delay (ZTD). For the version 1, it was developed a model with horizontal resolution of 100 km, which was updated with Eta model, with resolution of 20 km. This paper provides the most significative details of the current version, as well an evaluation of its quality, using for such ZTD estimates from GPS data collect at RBMC. Comparing to the old version, considerable improvement could be observed from the new model, mainly in Brasilia and Curitiba, reaching up to 55% improvement. When all stations were used in the quality control, almost null bias and RMS of about 4 to 5 cm could be observed.

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The nature of this thesis is interventionist and aims to create an alternative on how to control and evaluate the public policies implementation developed at the Institute for Technical Assistance and Rural Extension of Rio Grande do Norte State. The cenarium takes place in a public institution , classified as a municipality that belongs to the Rio Grande do Norte government and adopts the design science research methodology , where it generates a set of artifacts that guide the development of a computerized information system . To ensure the decisions, the literature was reviewed aiming to bring and highlight concepts that will be used as base to build the intervention. The use of an effective methodology called Iconix systems analysis , provides a software development process in a short time . As a result of many artifacts created by the methodology there is a software computer able of running on the Internet environment with G2C behavior, it is suggested as a management tool for monitoring artifacts generated by the various methods. Moreover, it reveals barriers faced in the public companies environment such as lack of infrastructure , the strength of the workforce and the executives behavior

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Autism comprises a heterogeneous group of neurodevelopmental disorders that affects the brain maturation and produces sensorial, motor, language and social interaction deficits in early childhood. Several studies have shown a major involvement of genetic factors leading to a predisposition to autism, which are possibly affected by environmental modulators during embryonic and post-natal life. Recent studies in animal models indicate that alterations in epigenetic control during development can generate neuronal maturation disturbances and produce a hyper-excitable circuit, resulting in typical symptoms of autism. In the animal model of autism induced by valproic acid (VPA) during rat pregnancy, behavioral, electrophysiological and cellular alterations have been reported which can also be observed in patients with autism. However, only a few studies have correlated behavioral alterations with the supposed neuronal hyper-excitability in this model. The aim of this project was to generate an animal model of autism by pre-natal exposure to VPA and evaluate the early post-natal development and pre-puberal (PND30) behavior in the offspring. Furthermore, we quantified the parvalbumin-positive neuronal distribution in the medial prefrontal cortex and Purkinje cells in the cerebellum of VPA animals. Our results show that VPA treatment induced developmental alterations, which were observed in behavioral changes as compared to vehicle-treated controls. VPA animals showed clear behavioral abnormalities such as hyperlocomotion, prolonged stereotipies and reduced social interaction with an unfamiliar mate. Cellular quantification revealed a decrease in the number of parvalbumin-positive interneurons in the anterior cingulate cortex and in the prelimbic cortex of the mPFC, suggesting an excitatory/inhibitory unbalance in this animal model of autism. Moreover, we also observed that the neuronal reduction occurred mainly in the cortical layers II/III and V/VI. We did not detect any change in the density of Purkinje neurons in the Crus I region of the cerebellar cortex. Together, our results strengthens the face validity of the VPA model in rats and shed light on specific changes in the inhibitory circuitry of the prefrontal cortex in this autism model. Further studies should address the challenges to clarify particular electrophysiological correlates of the cellular alterations in order to better understand the behavioral dysfunctions

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Bipolar disorder has been growing in several countries. It is a disease with high mortality and has been responsible by the social isolation of the patients. Bipolar patients have alterations in circadian timing system, showing a phase shift in various physiological variables. There are several arguments demonstrating alterations in circadian rhythms may be part of the bipolar disorder pathophysiology. Given the necessity for further elucidation, the goal of this study was to validate the forced desynchronization protocol as an animal model for bipolar disorder. To do this, Wistar rats were submitted to a forced desynchronization protocol which consists in a symmetrical light dark cycle with 22h. Under this protocol, rats dissociate the locomotor activity rhythm into two components: one synchronized to the light / dark cycle with 22h, and another component with period longer than 24 hours following the animal endogenous period. These rhythms with different periods sometimes there is coincidence, which we named CAP (Coincidence Active Phase) and the opposite phase, non-coincidence, called NCAP (Non-Concidence Active Phase). The hypothesis is that in CAP animals present a mania-like behavior and animals in NCAP depressive-like behavior. We found some evidence described in detail throughout this thesis. In sum, the animals under forced desynchronization protocol were more stressed, showed an increase in stereotypic behaviors such as grooming and reduction in other behaviors such as risk assessment and vertical exploration when compared to the control group. The CAP animals showed increased locomotor activity, especially during the dark phase when compared to controls (rats under T24) and less depressive behavior in the forced swim test. The animals in NCAP showed a higher anxiety in elevated plus maze, but they don t have ahnedonia. The animals under dissociation have more labeled 5HT1A cells at the amygdala area, which appoint that they have more amygdala inhibition. Taking these data together, we could partially validated the forced desynchronization protocol as an animal model for mood oscillations

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This discourse analyzes the technical assistance concerning the rural settlement, which is seen as a demand of the social movement that claims for agrarian reformation, and is a goal of II PNRA, launched in may 2004, as a essential national public politics on process of building and consolidation of settlement and familiar agriculture, proposing the return of technical assistance service and rural extension in Brazil, which were started in the and of 1940 s. We analyze, in particular, the technical assistance program, social and environmental agrarian reformation, on model settlement, a program created, especially, to the rural settlements, coordinated by INCRA. Based on the documental analyze and local study, it is noticed that the experience of technical assistance implemented on model settlement shows the non continuation and fragility on technical assistance actions to rural workers. This context goes against the lately technical assistance governmental apparatus, which ensures to make settlements stronger, to support and to get important the familiar agriculture system. This way, technical assistance execution, trough the tertiary service, follows the neoliberal strategy and, the State, besides decreases the estimate to public politics, takes its actions control from the State to the shared control through partnership and transferring of responsibility, expressing its historic lack of attention to the worker class demands. In spite of workers resistance, expectative and hope, the lack of these services, as well as the other politics deficiencies, which are necessary to the settlements, are endangering its activities and threatening its survival in the settlement

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A Internet atual vem sofrendo vários problemas em termos de escalabilidade, desempenho, mobilidade, etc., devido ao vertiginoso incremento no número de usuários e o surgimento de novos serviços com novas demandas, propiciando assim o nascimento da Internet do Futuro. Novas propostas sobre redes orientadas a conteúdo, como a arquitetura Entidade Titulo (ETArch), proveem novos serviços para este tipo de cenários, implementados sobre o paradigma de redes definidas por software. Contudo, o modelo de transporte do ETArch é equivalente ao modelo best-effort da Internet atual, e vem limitando a confiabilidade das suas comunicações. Neste trabalho, ETArch é redesenhado seguindo o paradigma do sobreaprovisionamento de recursos para conseguir uma alocação de recursos avançada integrada com OpenFlow. Como resultado, o framework SMART (Suporte de Sessões Móveis com Alta Demanda de Recursos de Transporte), permite que a rede defina semanticamente os requisitos qualitativos das sessões para assim gerenciar o controle de Qualidade de Serviço visando manter a melhor Qualidade de Experiência possível. A avaliação do planos de dados e de controle teve lugar na plataforma de testes na ilha do projeto OFELIA, mostrando o suporte de aplicações móveis multimídia com alta demanda de recursos de transporte com QoS e QoE garantidos através de um esquema de sinalização restrito em comparação com o ETArch legado

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OBJETIVO: Verificar a aterogenicidade do modelo de hipercolesterolemia por suplementação alimentar com gema de ovo em coelhos e seu uso como modelo de aterosclerose experimental de baixo custo. MATERIAL E MÉTODO: Foram utilizados 14 coelhos divididos em dois grupos de sete animais: grupo controle (G1), que recebeu ração comercial ad libitum, e grupo tratado (G2), que foi alimentado com dieta suplementada com gema de ovo. Ambos os grupos foram alimentados por 90 dias. Foram realizadas dosagens do perfil lipídico dos animais nos momentos 0, 30, 60 e 90 dias. Ao término do período experimental, os animais foram submetidos a eutanásia e retirada da aorta e de seus ramos diretos para realização de estudo anatomopatológico. RESULTADOS Apenas no grupo G2 houve aumento significativo nos níveis de colesterol total e frações. Ao exame macroscópico, foram observadas estrias gordurosas no arco aórtico e aorta abdominal e, à microscopia, acúmulos lipídicos discretos na íntima da aorta abdominal, renal, carótida, transição toracoabdominal e femoral. Portanto, a dieta com gema de ovo provocou aterosclerose leve no animal de experimentação e alterações equivalentes àquelas provocadas pelo colesterol purificado comercial quando fornecido em baixa dosagem. Assim sendo, a gema de ovo pode ser utilizada como fonte de colesterol alimentar de baixo custo em modelos de aterosclerose experimental.

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OBJETIVO: O presente estudo teve por objetivo caracterizar as alterações clínicas e laboratoriais do rato portador de Diabetes Mellitus induzido pela administração endovenosa de aloxana. MÉTODOS: Os animais foram distribuídos, por sorteio, em dois grupos experimentais: Grupo Controle Normal (G1), constituído de 25 animais sadios, e Grupo Diabético (G2), formado por 25 animais diabéticos graves, que foram avaliados em cinco momentos (1, 3, 6, 9 e 12 meses) de seguimento, tendo sido estudados os seguintes parâmetros: evolução clínica (peso, ingestão hídrica, ingestão alimentar e diurese) e exames bioquímicos (glicemia de jejum, glicose urinária, glicosúria, cetonúria, colesterol total, colesterol HDL, triglicérides e lipídios). RESULTADOS: A injeção de aloxana 2% na via endovenosa do rato acompanhou-se de um índice de mortalidade de 39%, tendo produzido diabetes grave também em 39% dos animais. O diabetes foi caracterizado por queda progressiva do peso corporal, elevação substancial da ingestão hídrica, ingestão alimentar e da diurese, com valores glicêmicos acima de 300 mg/dl, glicosúria 3+ e, eventualmente, cetonúria. O diabetes não altera o perfil de colesterol e lípides de ratos a longo prazo. CONCLUSÃO: Nossos estudos revelam que a aloxana produz, no rato, alterações clínicas e laboratoriais características de diabetes grave, as quais possibilitam estudos a longo prazo do diabetes.

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This study analysed the creation of businesses by entrepreneur women in the Currais Novos city, looking for verifying if they used making decision processes aligned to the Effectuation logic throughout the creation of their companies. To this, was accomplished a multiple cases and exploratory study, whit a qualitative approach of analyse, using the thematic life history technique that match accounts and semi-structured interview route, being accomplished like a long interview, where the researcher interact with the informer continuously. The semi-structured interview route was created by the adaptation of the interview route used by Tasic (2007). The present study appealed to a intentional selection of individuals in function of their importance in relation to the boarded theme. This means that the individuals were chosen in function of their social and theoretical representatively inside the considered situation. The participant individuals of this research were five entrepreneur women that act in the Currais Novos city, owners of five different companies. To the data treatment and analyse, was chosen the content analyse technique. This study worked with a priori theoretical categories. The categories of analyse in this study was obtained with base in the Effectuation approach (SARASVATHY, 2001a, 2001b, 2008), that is an alternative model of making decision to the classic model based in the causality principle. These categories are Clarity of Initial Aims , Tolerance to the Lost and Initials Investments , Control of Resources ( who I am , what I know and who I know ) and Promoting Over Contingencies . As result, the entrepreneur women researched, in a general way, hadn t clear initial aims at the companies creation moment, hadn t aversion to the risk to lose the time and the money that they were investing in the company in formation, they highlighted the products and services identity that offered with a strong link with Seridó region, they had experience in the field of activity in which they decided to open their companies, had the commitment of partners in the beginning of the business and they knew to transform the initial difficulties in opportunities. By the end, this study conclude that the entrepreneur women studied used, in a big part, making decision processes aligned to the Effectuation logic throughout the creation of their companies

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Fucans seaweed Lobophora variegata estructures are known for their chemical and biological properties. In this study, we analyzed, the action of fucans L. variegata and the fractions purified with acetone in Zymosan-induced arthritis. After differential fractionation with acetone, six fractions were obtained and named F0.3, F0.5, F0.8, F1, F1.5 and F2. The results showed that the fraction F1 showed high yield (51.9%) and was chosen for studies of antioxidant activity and induced arthritis. Nuclear magnetic resonance (NMR) of 13C showed signals at 103.3 and 15.78 ppm that are assigned to links β13 galactose and of the C6 methyl fucose, respectively. The infrared (IR) showed absorbance at 1238 and 850 cm-1 which are attributed to sulfate. The fraction F1 showed antioxidant activities in vitro. For analysis of inflammatory parameters chosen the polysaccharide was administered in different doses (25, 50 and 75 mg / kg ip, per body weight) and diclofenac sodium (5 mg / kg ip) and L-NAME (25 mg / kg ip) in groups of animals (n = 6). After 6 h, were analyzed for cellular influx and levels of nitrite. In experiment five days, were made analysis of swelling and serum TNF-α. Histopathological analysis were performed for confirmation of results. The fraction F1 (25, 50 and 75 mg / kg ip) reduced the cellular influx (52.1 to 96.7%) and nitric oxide levels (27.2 - 39%) compared to control group. The reduction of edema (63.4 - 100%) and serum TNF-α (p <0.001) were observed when the polysaccharide F1 administered at a dose (50 mg / kg) These results suggest that these heterofucanas of Lobophora variegata have besides the activity antioxidant and potential anti-inflammatory activity in arthritis induced by zymosan

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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The separation methods are reduced applications as a result of the operational costs, the low output and the long time to separate the uids. But, these treatment methods are important because of the need for extraction of unwanted contaminants in the oil production. The water and the concentration of oil in water should be minimal (around 40 to 20 ppm) in order to take it to the sea. Because of the need of primary treatment, the objective of this project is to study and implement algorithms for identification of polynomial NARX (Nonlinear Auto-Regressive with Exogenous Input) models in closed loop, implement a structural identification, and compare strategies using PI control and updated on-line NARX predictive models on a combination of three-phase separator in series with three hydro cyclones batteries. The main goal of this project is to: obtain an optimized process of phase separation that will regulate the system, even in the presence of oil gushes; Show that it is possible to get optimized tunings for controllers analyzing the mesh as a whole, and evaluate and compare the strategies of PI and predictive control applied to the process. To accomplish these goals a simulator was used to represent the three phase separator and hydro cyclones. Algorithms were developed for system identification (NARX) using RLS(Recursive Least Square), along with methods for structure models detection. Predictive Control Algorithms were also implemented with NARX model updated on-line, and optimization algorithms using PSO (Particle Swarm Optimization). This project ends with a comparison of results obtained from the use of PI and predictive controllers (both with optimal state through the algorithm of cloud particles) in the simulated system. Thus, concluding that the performed optimizations make the system less sensitive to external perturbations and when optimized, the two controllers show similar results with the assessment of predictive control somewhat less sensitive to disturbances

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With the technology progess, embedded systems using adaptive techniques are being used frequently. One of these techniques is the Variable Structure Model- Reference Adaptive Control (VS-MRAC). The implementation of this technique in embedded systems, requires consideration of a sampling period which if not taken into consideration, can adversely affect system performance and even takes the system to instability. This work proposes a stability analysis of a discrete-time VS-MRAC accomplished for SISO linear time-invariant plants with relative degree one. The aim is to analyse the in uence of the sampling period in the system performance and the relation of this period with the chattering and system instability

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The current work was developed on the dune systems of the Parque das Dunas and Barreira do Inferno. These places are located in the cities of Natal and Parnamirim (RN, Brazil), respectively. This project has the purpose of developing the deterministic model on a specific blowout at Parque das Dunas, based in the geophysical interpretations of the lines gotten with the Ground Penetration Radar and the planialtimetric acquisitions of the topographical surface of the land. Also analyses of the vulnerability/susceptibility of these dune systems had been done in relation to the human pressures. To develop its deterministic model, it is necessary to acquire inner and outer geometries of the cited blowout. In order to depict inner geometries underneath the surface are used the GPR observing the altimetric control for topographical correction of the GPR lines. As for the outer geometries, the geodesic GPS gives us the planialtimetric points (x, y and z points) with milimetric precision, resulting in high-resolution surfaces. Using interpolation methods of the planialtimetric points was possible create Digital Elevations Models (DEM´s) of these surfaces. As a result, 1,161.4 meters of GPR lines were acquired on the blowout at the Parque das Dunas and 3,735.27 meters on the blowout at the Barreira do Inferno. These lines had been acquired with a 200 MHz antenna, except the 7 and 8 lines, for which we had been used a 100 MHz antenna. The gotten data had been processed and interpreted, being possible to identify boundary surfaces of first, second and third order. The first order boundary surface is related with the contact of the rocks of the Barreiras Group with the aeolian deposits. These deposits had been divided in two groups (Group 1 and Group 2) which are related with the geometry of stratum and the dip of its stratifications. Group 1 presented stratum of sigmoidal and irregular geometries and involved bodies where the reflectors had presented dips that had varied of 20 to the 28 degrees for the Parque das Dunas blowout and of 22 to the 29 degrees for the Barreira do Inferno blowout. Usually, it was limited in the base for the first order surface and in the top for the second order surface. Group 2 presented stratum of trough, wedge or lens geometries, limited in the base for the second order vi surface, where the corresponding deposits had more shown smoothed reflectors or with dips of low angle. The Deterministic and Digital Elevation Models had been developed from the integration and interpretation of the 2D data with the GOCAD® program. In Digital Elevations Models it was possible to see, for the localities, corridor or trough-shaped blowouts. In Deterministic Model it was possible to see first and second order boundary surfaces. For the vulnerability/susceptibility of the dune systems it was applied the methodology proposal by Boderè al (1991); however the same one did not show adequate because it evaluates actual coastal dunes. Actual coastal dunes are dunes that are presented in balance with the current environmental conditions. Therefore, a new methodology was proposal which characterizes the supplying and activity sedimentary, as well as the human pressures. For the methodology developed in this work, both the localities had presented a good management. The Parque das Dunas was characterized as a relic dune system and the Barreira do Inferno was characterized as a palimpsestic dune system. Also two Thematic Maps had been elaborated for the environmental characterization of the studied dune systems, with software ArcGis 8.3, and its respective data bases