27 resultados para Fluxo crítico

em Universidade Federal do Rio Grande do Norte(UFRN)


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ENDERS, Bertha Cruz ; BRITO RS ; MONTEIRO, Akemi Ywata. Analise conceitual e pensamento critico: uma relacao complementar na enfermagem. Rev Gaucha Enferm, Porto Alegre (RS) 2004 dez;25(3):295-305.

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O propósito deste trabalho é mostrar a relação entre o processo de análise conceitual e as habilidades de pensamento crítico na enfermagem. Utilizando uma abordagem de ensaio discursivo, argumenta-se que a técnica de análise conceitual promove a criticidade em alunos de enfermagem. Os passos da atividade de análise são examinados quanto às operações cognitivas neles inseridas e que representam habilidades de raciocínio crítico. Reflete-se sobre a análise conceitual como atividade didática na promoção do pensamento crítico em uma experiência com alunos de graduação. Conclui-se que os dois processos se complementam no repensar e no enfrentamento de desafios na enfermagem

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Until the early 90s, the simulation of fluid flow in oil reservoir basically used the numerical technique of finite differences. Since then, there was a big development in simulation technology based on streamlines, so that nowadays it is being used in several cases and it can represent the physical mechanisms that influence the fluid flow, such as compressibility, capillarity and gravitational segregation. Streamline-based flow simulation is a tool that can help enough in waterflood project management, because it provides important information not available through traditional simulation of finite differences and shows, in a direct way, the influence between injector well and producer well. This work presents the application of a methodology published in literature for optimizing water injection projects in modeling of a Brazilian Potiguar Basin reservoir that has a large number of wells. This methodology considers changes of injection well rates over time, based on information available through streamline simulation. This methodology reduces injection rates in wells of lower efficiency and increases injection rates in more efficient wells. In the proposed model, the methodology was effective. The optimized alternatives presented higher oil recovery associated with a lower water injection volume. This shows better efficiency and, consequently, reduction in costs. Considering the wide use of the water injection in oil fields, the positive outcome of the modeling is important, because it shows a case study of increasing of oil recovery achieved simply through better distribution of water injection rates

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In the present study we elaborated algorithms by using concepts from percolation theory which analyze the connectivity conditions in geological models of petroleum reservoirs. From the petrophysical parameters such as permeability, porosity, transmittivity and others, which may be generated by any statistical process, it is possible to determine the portion of the model with more connected cells, what the interconnected wells are, and the critical path between injector and source wells. This allows to classify the reservoir according to the modeled petrophysical parameters. This also make it possible to determine the percentage of the reservoir to which each well is connected. Generally, the connected regions and the respective minima and/or maxima in the occurrence of the petrophysical parameters studied constitute a good manner to characterize a reservoir volumetrically. Therefore, the algorithms allow to optimize the positioning of wells, offering a preview of the general conditions of the given model s connectivity. The intent is not to evaluate geological models, but to show how to interpret the deposits, how their petrophysical characteristics are spatially distributed, and how the connections between the several parts of the system are resolved, showing their critical paths and backbones. The execution of these algorithms allows us to know the properties of the model s connectivity before the work on reservoir flux simulation is started

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Water injection is the most widely used method for supplementary recovery in many oil fields due to various reasons, like the fact that water is an effective displacing agent of low viscosity oils, the water injection projects are relatively simple to establish and the water availability at a relatively low cost. For design of water injection projects is necessary to do reservoir studies in order to define the various parameters needed to increase the effectiveness of the method. For this kind of study can be used several mathematical models classified into two general categories: analytical or numerical. The present work aims to do a comparative analysis between the results presented by flow lines simulator and conventional finite differences simulator; both types of simulators are based on numerical methods designed to model light oil reservoirs subjected to water injection. Therefore, it was defined two reservoir models: the first one was a heterogeneous model whose petrophysical properties vary along the reservoir and the other one was created using average petrophysical properties obtained from the first model. Comparisons were done considering that the results of these two models were always in the same operational conditions. Then some rock and fluid parameters have been changed in both models and again the results were compared. From the factorial design, that was done to study the sensitivity analysis of reservoir parameters, a few cases were chosen to study the role of water injection rate and the vertical position of wells perforations in production forecast. It was observed that the results from the two simulators are quite similar in most of the cases; differences were found only in those cases where there was an increase in gas solubility ratio of the model. Thus, it was concluded that in flow simulation of reservoirs analogous of those now studied, mainly when the gas solubility ratio is low, the conventional finite differences simulator may be replaced by flow lines simulator the production forecast is compatible but the computational processing time is lower.

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The present study provides a methodology that gives a predictive character the computer simulations based on detailed models of the geometry of a porous medium. We using the software FLUENT to investigate the flow of a viscous Newtonian fluid through a random fractal medium which simplifies a two-dimensional disordered porous medium representing a petroleum reservoir. This fractal model is formed by obstacles of various sizes, whose size distribution function follows a power law where exponent is defined as the fractal dimension of fractionation Dff of the model characterizing the process of fragmentation these obstacles. They are randomly disposed in a rectangular channel. The modeling process incorporates modern concepts, scaling laws, to analyze the influence of heterogeneity found in the fields of the porosity and of the permeability in such a way as to characterize the medium in terms of their fractal properties. This procedure allows numerically analyze the measurements of permeability k and the drag coefficient Cd proposed relationships, like power law, for these properties on various modeling schemes. The purpose of this research is to study the variability provided by these heterogeneities where the velocity field and other details of viscous fluid dynamics are obtained by solving numerically the continuity and Navier-Stokes equations at pore level and observe how the fractal dimension of fractionation of the model can affect their hydrodynamic properties. This study were considered two classes of models, models with constant porosity, MPC, and models with varying porosity, MPV. The results have allowed us to find numerical relationship between the permeability, drag coefficient and the fractal dimension of fractionation of the medium. Based on these numerical results we have proposed scaling relations and algebraic expressions involving the relevant parameters of the phenomenon. In this study analytical equations were determined for Dff depending on the geometrical parameters of the models. We also found a relation between the permeability and the drag coefficient which is inversely proportional to one another. As for the difference in behavior it is most striking in the classes of models MPV. That is, the fact that the porosity vary in these models is an additional factor that plays a significant role in flow analysis. Finally, the results proved satisfactory and consistent, which demonstrates the effectiveness of the referred methodology for all applications analyzed in this study.

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Durante as últimas décadas, as indústrias farmacêuticas têm despertado grande interesse em óleos vegetais e vários extratos de planta por causa da sua baixa toxicidade e alta biodegrabilidade. O óleo de copaíba (Cop) é usado in natura na medicina popular como anti-inflamatório e antimicrobiano para tratar várias doenças, tais como inflamação da garganta, úlceras e infecções urinárias e pulmonares. Emulsões são sistemas dispersos termodinamicamente instáveis que consistem em dispersões de gotículas microscópicas em outro líquido imiscível. O objetivo deste trabalho foi preparar diferentes emulsões de Cop, determinar o EHL crítico deste óleo e avaliar a sua estabilidade, além de realizar estudos comparativos entre diferentes métodos de construção de diagramas de fases. As emulsões foram preparadas pelo método de inversão de fases variando as proporções de EHL de 4,7 a 16,7. A estabilidade foi determinada por vários métodos e os diagramas de fases foram produzidos pelo método de titulação usando diferentes procedimentos de agitação. As emulsões a base de Cop com EHL entre 12,7 e 15,7 foram as mais estáveis. As emulsões apresentaram boa estabilidade em curto e longo prazo, aspecto leitoso e baixos valores de índice de cremagem. Diferentes sistemas coloidais foram produzidos a partir dos diagramas de fases dependendo do processo de agitação. Baseado nesses métodos, o valor determinado de EHL do Cop foi 14,8, as emulsões permaneceram estáveis por mais de um ano e estes resultados indicam que o estudo das emulsões de Cop pode ser um promissor veículo de liberação tópica de fármacos e ativos cosméticos

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Chronic lymphocytic leukemia (B-CLL) is a clonal proliferation of mature B lymphocytes characterized by indolent clinical course. Biologically this clonallity is characterized by low expression of surface immunoglobulin (sIg) with restriction to a single immunoglobulin light chain associated with high expression of CD5 antigen and positivity to B cell antigens lymphocytes such as CD19, CD20 and CD23 and negativity to FMC7. The immunological profile and morphological analysis of lymphoid cells are the main means for the differential diagnosis of B-CLL from other chronic lymphoproliferative diseases. The aim of this study was to evaluate the expression pattern of a variety of membrane antigens in leukemic cells originating from patients with B-CLL. In this study, peripheral blood samples from 80 patients with B-CLL were analyzed by multiparametric flow cytometry in addition to routine hematologic exams, using a panel of monoclonal antibodies (MoAb): CD45/CD14, CD3/CD19/CD45, CD4/CD8 / CD3, CD20/CD5/CD3, CD3/CD16-56/CD45, CD2/CD7, FMC7/CD23, CD103/CD22/CD20, HLADR/CD38, CD10/CD19, CD1a, CD11b and also IgM/gD, kappa and lambda immunoglobulin light chains for the detection of surface immunoglobulin and clonal restriction for immunoglobulin light chain. The Hematological data were obtained from the hematological analyzer and cytomorphological analysis in blood film stained by Leishmann. The study samples consisted of 45 men and 35 women, ages ranging from 55 to 84 years (mean 65 years). Complete white blood count showed count ranging from 10.0 to 42.0 x 109/l. (mean 50.0 x 109/l) and lymphocytes count greater than 5.0 x 109/l in all cases. The neoplastic cells displayed B-CLL phenotype (CD5+/CD19+/CD20+/HLADR+/CD23+) in the vast majority of the cases, associated to failed to stain for T cell markers (CD1a, CD2, CD4, CD3, CD7, CD8), CD103, CD14 and FMC7. Leukemic cells of most patients also expressed low intensity of IgM and IgD with restricted kappa light chain, in most cases (59,7%). This observation highlights the importance of immunophenotyping for correct diagnosis of chronic lymphoproliferative syndromes and the panel of MoAb used was sufficient for diagnostic confirmation of B-CLL

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The acute myeloid leukemia (AML) is a disease in which malignant myeloblasts expand, build up and suppress normal hematopoietic activity would represent a major diagnostic challenge. With the advent of immunophenotyping by flow cytometry, the diagnosis of these tumors have become more faithful, facilitating the treatment and monitoring of patients. The objectives of this study: diagnosis and classification of AML based on immunophenotyping by flow cytometry with a panel of AcMo specific for acute leukemias, set the frequency of AML in samples from patients with acute leukemias sent to the Department of Hematology Blood Center of Rio Grande do Norte - HEMONORTE, establish standards of antigen expression for different subtypes of acute leukemia and its correlation with the newly diagnosed cases refractory to treatment and recurrence of the disease, standardization of methods for detection and labeling of surface antigens by flow cytometry and intracytoplasmic flow, and observe the frequency of acute leukemia with aberrant phenotypes rare. During the study, 351 were diagnosed acute leukemia, and 179 (51%) classified as AML and 172 (49%) and ALL, which were excluded from the present work. Of the 179 AML, 92 (51.4%) were female and 87 (48.6%) were male, with ages ranging from 3 to 95 years of ag, with higher incidence in individuals in the age group of 41 to 65. Splenomegaly was the clinical finding more present, a total of 147 cases (82.1%), followed by hepatomegaly present in 132 cases (73.7%). The hemorrhagic events were observed in 55 cases (30.7%). Lymphadenopathy in turn was detected in 20 of 179 cases (11.2%). In order to classify subtypes of AML, we used a large panel of monoclonal antibodies, obtaining the following results: AML M0, 02 (1.1%) AML M1, 40 (22.3) AML M2, 60 (33.5) AML M3, 22 (12.3%) AML M4, 10 (5.6) AML M5, 13 (7.3%) AML M6 06 (3.4%) and AML M7 01 (0.6%). We observed some cases with aberrant expression of some antigens such as CD7, CD4, CD19, CD3, CD5 and TdT, CD 7 was present in 30 (16.8%), CD4 in 5 (2.8%), the CD 3 in 5 (2.8%), the CD19 in 3 (1.7%), the CD5 in 3 (1.7%) and TDT was in 7 (3.9%) cases of AML .the CD8 and CD79a was present in only a 1 case.

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It is an ethnographic work that has an objective of verifying devices throngh the residents of a low income suburban area, and the way they deal with their social relations through sonsumerism (and the aspiration connected to it), the symbolic character acquired through consumer goods, understood as one of the fundamental components for the comprehension of the web as relations that established, Though consumerism, individuais will reveal ways of communication, of the status, of creating new forms of action and identification. Using the principal that believes in a web of symbolic significance where own individuais develop their impressions, as a resource to look at their own bodies, a social order (yet unstable), and the process of inclusion in a broader society. In conclusion, the act of consuming is more than a perspective that establishes statistics on consumer goods, with their ways of production, circulation and economic functioning: it is also a way of perceiving a collection mapped by consumers individually and socially, and by those means organizing, classifying and identifyring the social world

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This work seeks to examine the historical relationships established between liberalism and democracy, questioning the apparent inseparability between the two ideologies. Methodologically construct a hypothetical dialogue with the Italian thinker Norberto Bobbio, one of the most important systematizers of liberal democracy, defending a theoretical and conceptual complementarity between the two ideologies. Following the Bobbio theoretical propose, it presents the political contributions of classical liberalism that the Italian thinker identify as logical and axiological antecedent of the modern democracy, naturalizing and universalizing the principles and ideals of classical liberalism. Going counter, it problematizes the political contributions of classical liberalism, emphasizing the tension between liberal theory and its practice, between the declared political principles and their translation into concrete historical reality, reserving rights and freedoms to property minority and severe restrictions to the majority. The critical analysis of classical liberalism allows questioning the privilege position that Bobbio reserves to the liberalism in the democracy history, to restore the important contribution of illiberal politics currents in the civil, political and social rights history, advocating the democracy with its social character, inclusive and participatory

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This collaborative research is a qualitative approach, from historical and cultural perspective, made about a teacher of third grade of basic education in the area of history, in the municipality of Caicó / RN. It has as objective to investigate, in a collaborative action, if the design process of teaching and learning the discipline of history based on the relationship before / after allows the development of critical reflective thinking of the teacher in school practices. The theoretical and methodological approaches are supported in the postulates of Vygotsky (1998), Rubinstein (1973) and Linblinskaia (1979), among others, whose understanding has led us to reflect if the teacher develops the reflective critical-thinking in history discipline classes. The complexity of the study led us to an analysis exercise, using different methodological procedures, such as: bibliographic review of the literature, considering also the literature of the history area, interviews, observation in the classroom, video recordings and reflective sessions, enabling clarify the construction and reconstruction of thought that the teacher had been developing during the process of teaching and learning. The test results point to a dichotomy between theory and practice, and also to a certain fragility in the position of professor in teaching and learning the discipline of history, at the third grade of basic education. The teacher recognizes that she requires a theoretical deepening with more intensity, as a process of continuous training to improve the practice of teaching in history school, though, stating in her speech that her teaching practice is based on critical reflection. However, she presents serious limitations in classroom practices. We conclude that, although she has shown willing to work on a critical perspective of reality, showed also poor change at school practices, starting to reflect about her own actions, pointing her limits and the changes needed that didn t become reality yet. It s necessary a formative process for her. The study therefore showed that even with the sessions and reflective of deepening theoretical studies, the teacher does not change its profile, while maintaining its traditional vision in any pedagogical action. This research recommends the formation of school groups for further studies and discussion on the practices of education in history area from a reflective-critical thought perspective as a mean of personal and professional development

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In the passage of life, the labyrinth of songs and corners are propitious ways for a better comprehension, perception and incorporation of learnings that emerge from our subjectiveness in a magic caught by senses. Eyesight, taste, hearing, touch and smell in communication with the world, put us in front of cultural diversities. The ludicity accumulated by experiences promote the flow of hilarious and concrete discoveries that express themselves in work and leisure demonstrations. Such reflections emerge indicators to the problematic construction centralized in the incorporation of cultural experience knowledge to the formation process and professional interventions in this rule and area. From this significant problematic, aiming to deepen studies, we favored leisure as field of investigative production in full expansion. This, for sure, was an exercise of qualification that guided us through meander of education and made us dip into studies about the corporeity. A research in which the scenery was painted and constructed with the complicity of the culture lived with shine, colors, rhythm and drummings of one of the most present cultural cycles: carnival. Recognized as a stimulant for beauty, participation, socialization, and helped us to enter in the essence of gestures and expressions of corporeity, to think, elaborate and socialize a critic-scientific knowledge which, appropriating from the rhythm of colors, of sounds, of tonalities, of senses and of meanings impregnated in the web of life. All these things seduced the researcher, making imagination flow amid ludic-creative dialogues with the imaginary of researchers creation and production in the rule and area of leisure, education and corporeity. Option that made us outline as objective to investigate and interpret how leisure teachers-researchers, from their studies, researches and interventions, locate and incorporate the knowledge from cultural experience to the formation process and intervention of professionals in this rule and in this area, emphasizing the contributions from this knowledge to fence and qualify this praxis. So, as living each cultural scenery, each epistemological contribution was feeding the production with images of the different versions of the Brazilian breedings, creating and raising expectations and new discoveries and newcomers. With the seriousness of a scientific study, we lived an xxiii academic experience with complex intensity, rigor and coherence, eliminating, step by step, the risks and limitations always present in a work of this magnitude. However, we weren t, even for one moment, alone. Our epistemic regard always maintained mediated by the principles of a methodological approach - the Etnomethodology, that while central guide provided us clues to unveil the lived world by our people-playful , in a universe of 15 members, that allowed themselves to comprehend, comment, analyze. This way, grasping the object in interactions arised and provoked by narrative interview, it was systematically dialected by (re) interpretation of images and formulations of people-playful, enriched by their beliefs, myths, conceptions and rituals inherent to knowledge from cultural experience, which each one attuned with Brazilian and international history, in a mixture of senses echoed from songs and tales. Inspired in drummings and percussions, clothing and choreographies of gestures and expressions, in mixtures produced in unit interactions in the multiplicity shown as necessary requests to the totality of life, with ludicity the rescue of the past, the conquest of present and the construction of future was the axle guide. This rich process of scientific creation made us realize that is possible qualify and empower the praxis in the rule and area of leisure incorporating the knowledge from cultural experience. What also becomes possible is the recuperation of objective revolutionaries and changing conditions of praxis itself with the view of strengthening and triggerment of vital elements in the rule and area of leisure. We also reaffirm that from this praxis emerge elements necessary to human formation in plenitude, by the appropriation of knowledge that guide the facing of challenges of a complex and plural world that valorize education, corporeity and leisure

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This work describes the study and the implementation of the vector speed control for a three-phase Bearingless induction machine with divided winding of 4 poles and 1,1 kW using the neural rotor flux estimation. The vector speed control operates together with the radial positioning controllers and with the winding currents controllers of the stator phases. For the radial positioning, the forces controlled by the internal machine magnetic fields are used. For the radial forces optimization , a special rotor winding with independent circuits which allows a low rotational torque influence was used. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed and radial positioning controllers to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The DSP resources used by the system are: the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system

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This work describes the study and the implementation of the speed control for a three-phase induction motor of 1,1 kW and 4 poles using the neural rotor flux estimation. The vector speed control operates together with the winding currents controller of the stator phasis. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed controls to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The main DSP recources used by the system are, respectively, the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system