969 resultados para Entrada e saída
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The present study has proposed a structural model to identify the reasons why individuals become voluntary, keep and exit this type of work. The empirical space was the Pastoral da Criança - social action agency of the National Conference of Bishops of Brazil (CNBB) - community-based institution that has its work based on solidarity and the sharing of knowledge. The theoretical framework has the context in which are volunteering studies in Brazilian and world level. Then discuss the various concepts of volunteering and presented the theoretical models of volunteer motivation. Studies of Mostyn (1983) and studies conducted by the BEPEGE-Base for Studies and Research in Management Policies and Strategies - in their line of research GERQUAL - Human Resource Management and Organizational Quality - of the Federal University of Rio Grande do Norte as Carvalho e Souza(2006), Souza, Medeiros e Fernandes (2006), Souza et al (2009, 2010), Cavalcante et al (2011a, 2011b, 2011c, 2011d) were the main theoretical references for the construction of the model that was tested. Data collection was done through a survey with 71 indicators, in 2 visits to cities from the Diocese of Pesqueira, Pernambuco. The first data collection occurred in the period between May 30 and June 3, 2011, in Buique/PE and the second collection happened in Pesqueira/PE, in St. Joseph Seminary, in the period between July 6-8, 2011. 720 questionnaires were collected. The sample was divided into two parts. Exploratory Factor Analysis was applied in first part and Confirmatory Factor Analysis - structural equation modeling - in the second half. The examination of the results achieved by the expectations, reasons for entry, reasons for staying and exit reasons showed that all hypotheses were accepted. So the motivation of voluntary Pastoral da Criança can be explained by a set of interactions between these five constructs: Altruistic, Affectionate, Amiable, Adjusted and Astute
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Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model
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Spatial-temporal dynamics of zooplankton in the Caravelas river estuary (Bahia, Brazil). The survey was conducted in order to describe the zooplankton community of the estuary Caravelas (Bahia, Brazil), to quantify and relate the patterns of horizontal and vertical transport with the type of tide (neap and spring) and tidal phase (flood and ebb). Zooplankton samples were collected with the aid of a suction pump (300L), filtered in plankton nets (300μm) and fixed in saline formalin 4%. Samples were collected at a fixed point (A1), near the mouth of the estuary, with samples taken at neap tides and spring tides during the dry and rainy seasons. Samples were collected for 13 hours, at intervals of 1 hour in 3 depths: surface, middle and bottom. Simultaneous collection of biological, we measured the current velocity, temperature and salinity of the water through CTD. In the laboratory, samples were selected for analysis in estereomicroscope, with 25 groups identified, with Copepoda getting the highest number of species. The 168 samples obtained from temporal samples were subsampled and processed on equipment ZooScan, with the aid of software ZooProcess at the end were generated 458.997 vingnettes. 8 taxa were identified automatically, with 16 classified as a semi-automatic. The group Copepoda, despite the limited taxonomic refinement ZooScan, obtained 2 genera and 1 species identified automatically. Among the seasons dry and wet groups Brachyura (zoea), Chaetognatha, and the Calanoid copepods (others), Temora spp., Oithona spp. and Euterpina acutifrons were those who had higher frequency of occurrence, appearing in more than 70% of the samples. Copepoda group showed the largest percentage of relative abundance in both seasons. There was no seasonal variation of total zooplankton, with an average density of 7826±4219 org.m-3 in the dry season, and 7959±3675 org.m-3 in the rainy season, neither between the types and phases of the tides, but seasonal differences were significant recorded for the main zooplankton groups. Vertical stratification was seen for the major zooplankton groups (Brachyura, Chaetognatha, Calanoida (other), Oithona spp, Temora spp. e Euterpina acutifrons). The scale of this stratification varied with the type (square or tide) and tidal phase (flood or ebb). The instantaneous transport was more influenced by current velocity, with higher values observed in spring tides to the total zooplankton, however, there was a variation of this pattern depending on the zooplankton group. According to the data import and export of total zooplankton, the outflow of organisms of the estuary was higher than the input. The results suggest that the estuary of Caravelas may influence the dynamics of organic matter to the adjacent coast, with possible consequences in National Marine Park of Abrolhos
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This work presents a proposal to detect interface in atmospheric oil tanks by installing a differential pressure level transmitter to infer the oil-water interface. The main goal of this project is to maximize the quantity of free water that is delivered to the drainage line by controlling the interface. A Fuzzy Controller has been implemented by using the interface transmitter as the Process Variable. Two ladder routine was generated to perform the control. One routine was developed to calculate the error and error variation. The other was generate to develop the fuzzy controller itself. By using rules, the fuzzy controller uses these variables to set the output. The output is the position variation of the drainage valve. Although the ladder routine was implemented into an Allen Bradley PLC, Control Logix family it can be implemented into any brand of PLCs
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The oscillations presents in control loops can cause damages in petrochemical industry. Canceling, or even preventing such oscillations, would save up to large amount of dollars. Studies have identified that one of the causes of these oscillations are the nonlinearities present on industrial process actuators. This study has the objective to develop a methodology for removal of the harmful effects of nonlinearities. Will be proposed an parameter estimation method to Hammerstein model, whose nonlinearity is represented by dead-zone or backlash. The estimated parameters will be used to construct inverse models of compensation. A simulated level system was used as a test platform. The valve that controls inflow has a nonlinearity. Results and describing function analysis show an improvement on system response
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Currently the uncertain system has attracted much academic community from the standpoint of scientific research and also practical applications. A series of mathematical approaches emerge in order to troubleshoot the uncertainties of real physical systems. In this context, the work presented here focuses on the application of control theory in a nonlinear dynamical system with parametric variations in order and robustness. We used as the practical application of this work, a system of tanks Quanser associates, in a configuration, whose mathematical model is represented by a second order system with input and output (SISO). The control system is performed by PID controllers, designed by various techniques, aiming to achieve robust performance and stability when subjected to parameter variations. Other controllers are designed with the intention of comparing the performance and robust stability of such systems. The results are obtained and compared from simulations in Matlab-simulink.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
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In this paper artificial neural network (ANN) based on supervised and unsupervised algorithms were investigated for use in the study of rheological parameters of solid pharmaceutical excipients, in order to develop computational tools for manufacturing solid dosage forms. Among four supervised neural networks investigated, the best learning performance was achieved by a feedfoward multilayer perceptron whose architectures was composed by eight neurons in the input layer, sixteen neurons in the hidden layer and one neuron in the output layer. Learning and predictive performance relative to repose angle was poor while to Carr index and Hausner ratio (CI and HR, respectively) showed very good fitting capacity and learning, therefore HR and CI were considered suitable descriptors for the next stage of development of supervised ANNs. Clustering capacity was evaluated for five unsupervised strategies. Network based on purely unsupervised competitive strategies, classic "Winner-Take-All", "Frequency-Sensitive Competitive Learning" and "Rival-Penalize Competitive Learning" (WTA, FSCL and RPCL, respectively) were able to perform clustering from database, however this classification was very poor, showing severe classification errors by grouping data with conflicting properties into the same cluster or even the same neuron. On the other hand it could not be established what was the criteria adopted by the neural network for those clustering. Self-Organizing Maps (SOM) and Neural Gas (NG) networks showed better clustering capacity. Both have recognized the two major groupings of data corresponding to lactose (LAC) and cellulose (CEL). However, SOM showed some errors in classify data from minority excipients, magnesium stearate (EMG) , talc (TLC) and attapulgite (ATP). NG network in turn performed a very consistent classification of data and solve the misclassification of SOM, being the most appropriate network for classifying data of the study. The use of NG network in pharmaceutical technology was still unpublished. NG therefore has great potential for use in the development of software for use in automated classification systems of pharmaceutical powders and as a new tool for mining and clustering data in drug development
Saída compulsória do estrangeiro do território nacional à luz dos direitos humanos: análise de casos
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This paper aims to review traditional concepts inherent to the general theory of the state and human rights, relating to the legal situation of foreign, understood as the subject of rights, especially when the is case of compulsory legal imposition of exit from national territory. After the serious violations during the Second World War and the importance acquired by the International Law of Human Rights, values as dignity, justice and equality are enshrined in the legal system and its respect required beyond the boundaries of any country. The creation of an international community, which is governed by rules that its members are subordinated, without distinction, as well as state - based on volunteerism, become inspired by one principled nature of these new concepts required of Global Society, as well as the adoption, influenced by neoconstitutionalism, to the model of State Constitutional rule of law, are opposed to the idea of state sovereignty connected to a superiority, absolute and unlimited power which recognizes no other above it, not even the basic principles or axioms that must govern the relationships internally. So looks for a concept of state that includes all the requirements of a democratic society, that have the people as the power holder, understanding that state element has undergone a relativization, because had to adapt to the contemporary values applicable to the individual, inserting in its concept, the indispensable obligation to protect the inalienable rights of citizens, regardless of with whom he have legal and political bond of nationality. It happens that, to consecrate these privileges to individuals, which, because they contain reference to values with supranational characteristics, are very abstract and are in constant collision course with internal rules, making it difficult to reconcile, it will use hermeneutics of human rights, due mainly to international courts, correlated with constitutional exegesis, in particular, legal principiologia, using, among others, the principles of reasonableness and proportionality, the systematic interpretation of the Constitution and international legal standards. Thus, it seek to enshrine the common foundation of all law , the link between the systems, namely, the dignity of human beings. Finally, it will see if Brazilian jurisdiction, through case studies, is tuned in line with these new paradigms, and in line with the International Bill of Human Rights, the Federal Constitution, the values and principles she hired
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The present work, based on the methodological principles of the Comprehensive Discourse Analysis, aimed, through the speech of twelve newly arrived students at the Pedagogy course of the Federal University of Rio Grande do Norte, to understand the moment students start university. It also aimed to analyze the relationship between the schools they were coming from and university entrance as well as the relationship between university and their new students. In the first part of the work, which focused on school knowledge, a comprehensive listening of the speeches of the students led primarily to a distinction, established by the students, between public and private schools, a distinction especially based on the view of superiority of private schools against public ones. The abovementioned interpretation is found in the discussion of the structural duality of Brazilian education which, historically, offers different pedagogical appliances among students of more priviledged social classes and those who come from lower levels of society. The overcome of this duality, aspired by the Brazilian Constitution of 1988, was stopped by the advent of a new economic model neoliberalism, which reinforced the differences between public and private when it prioritized the market on the economic, political and social relations, including educational projects. Impoverishment of public institutions and pauperization of the work of professors affected also the relationship between teachers and studens at the current institution. This is how the teacher becomes the greatest villain at the public management system. All of these references concerning differences in the quality of teaching at public and private schools, expressed by the students interviewed, however, were centered in the preparation for the entrance exam, called vestibular, thus showing a view that the relationship between the student and the school he came from is of a propedeutic kind and even so, reduced to a preparation for an entrance exam. In the second part of the work, which analyzed the relationship between newly arrived students and their university, it was noticed that the latter represents a whole new world. This world is seen as the change at the student´s social statute for now he is grown, takes more responsibilities and is socially respected. This change of attitude established by society and the discovery of a new world which requires more independence from the students, creates in them feelings of pride and fear and they feel insecure when it comes to making decision in the campus because now their decisions deliver a greater load of responsibility. This is when students understand they need to develop autonomy, which is seen, in this work, as the capacity to make conscious decisions. Nevertheless students expressed an understanding of autonomy as something that comes as a gift for those who enter university and not as a process that is constructed from social experiences. For these students, the need to be autonomous refers to the relationships with their teachers and the search for information. This search, however, is also related, according to interviews, to public school financial cuts, which penalize university, and to the lack of employers
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This thesis presents a new structure of robust adaptive controller applied to mobile robots (surface mobile robot) with nonholonomic constraints. It acts in the dynamics and kinematics of the robot, and it is split in two distinct parts. The first part controls the robot dynamics, using variable structure model reference adaptive controllers. The second part controls the robot kinematics, using a position controller, whose objective is to make the robot to reach any point in the cartesian plan. The kinematic controller is based only on information about the robot configuration. A decoupling method is adopted to transform the linear model of the mobile robot, a multiple-input multiple-output system, into two decoupled single-input single-output systems, thus reducing the complexity of designing the controller for the mobile robot. After that, a variable structure model reference adaptive controller is applied to each one of the resulting systems. One of such controllers will be responsible for the robot position and the other for the leading angle, using reference signals generated by the position controller. To validate the proposed structure, some simulated and experimental results using differential drive mobile robots of a robot soccer kit are presented. The simulator uses the main characteristics of real physical system as noise and non-linearities such as deadzone and saturation. The experimental results were obtained through an C++ program applied to the robot soccer kit of Microrobot team at the LACI/UFRN. The simulated and experimental results are presented and discussed at the end of the text
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This Dissertation aims to provide a communication mechanism between Digital TV viewers and interaction devices, such as robots, for example, placed on the environment from which a TV program is being live broadcasted. Such communication mechanism has the objective to allow viewers controll the Interaction Devices through their TV devices, using the broadcast channel present in Interactive Digital TV systems, and receive data from the devices by the broadcast channel. This system was projected as a middlewaer system where the Interaction Devices in the TV program set are interconnected, creating a Interactive Device Network. With this approach, the system is capable of manage the devices on the network, controlling the flow of coming and leaving elements, in a transparent way for the viewers. The system yet allows the Interaction Devices communicate each other, with a integrated communication channel with no worries about the physical communication layer
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An alternative nonlinear technique for decoupling and control is presented. This technique is based on a RBF (Radial Basis Functions) neural network and it is applied to the synchronous generator model. The synchronous generator is a coupled system, in other words, a change at one input variable of the system, changes more than one output. The RBF network will perform the decoupling, separating the control of the following outputs variables: the load angle and flux linkage in the field winding. This technique does not require knowledge of the system parameters and, due the nature of radial basis functions, it shows itself stable to parametric uncertainties, disturbances and simpler when it is applied in control. The RBF decoupler is designed in this work for decouple a nonlinear MIMO system with two inputs and two outputs. The weights between hidden and output layer are modified online, using an adaptive law in real time. The adaptive law is developed by Lyapunov s Method. A decoupling adaptive controller uses the errors between system outputs and model outputs, and filtered outputs of the system to produce control signals. The RBF network forces each outputs of generator to behave like reference model. When the RBF approaches adequately control signals, the system decoupling is achieved. A mathematical proof and analysis are showed. Simulations are presented to show the performance and robustness of the RBF network