Estabilidade e robustez de um controlador adaptativo indireto por um modelo de referência e estrutura variável

In this thesis, it is developed the robustness and stability analysis of a variable structure model reference adaptive controller considering the presence of disturbances and unmodeled dynamics. The controller is applied to uncertain, monovariable, linear time-invariant plants with relative degree one, and its development is based on the indirect adaptive control. In the direct approach, well known in the literature, the switching laws are designed for the controller parameters. In the indirect one, they are designed for the plant parameters and, thus, the selection of the relays upper bounds becomes more intuitive, whereas they are related to physical parameters, which present uncertainties that can be known easier, such as resistances, capacitances, inertia moments and friction coefficients. Two versions for the controller algorithm with the stability analysis are presented. The global asymptotic stability with respect to a compact set is guaranteed for both cases. Simulation results under adverse operation conditions in order to verify the theoretical results and to show the performance and robustness of the proposed controller are showed. Moreover, for practical purposes, some simplifications on the original algorithm are developed

Posicionamento e movimentação de um robô humanóide utilizando imagens de uma câmera móvel externa

This work proposes a method to localize a simple humanoid robot, without embedded sensors, using images taken from an extern camera and image processing techniques. Once the robot is localized relative to the camera, supposing we know the position of the camera relative to the world, we can compute the position of the robot relative to the world. To make the camera move in the work space, we will use another mobile robot with wheels, which has a precise locating system, and will place the camera on it. Once the humanoid is localized in the work space, we can take the necessary actions to move it. Simultaneously, we will move the camera robot, so it will take good images of the humanoid. The mainly contributions of this work are: the idea of using another mobile robot to aid the navigation of a humanoid robot without and advanced embedded electronics; chosing of the intrinsic and extrinsic calibration methods appropriated to the task, especially in the real time part; and the collaborative algorithm of simultaneous navigation of the robots

Desacoplamento de um gerador síncrono através de um controle adaptativo por modelo de referência baseado em funções de Base radial

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

Referência ao discurso do outro: uma análise de problemas de relações de sentido entre discurso citado direto e indireto citante no gênero monográfico

In this study we investigate the reference to other s discourse done it through the resource of direct cited discourse at background section in monographic texts produced by university students at the last phase of final work in their graduate Letras course. This work is guided in cited/related discourse studies in Bakhtin (2004), Authier-Revuz (1990, 1998, 2004), Maingueneau (1996, 2002), Charaudeau and Maingueneau (2004); in genre approaches developed by Bakhtin (2000); Maingueneau (1996, 2002); socio-discursive interaction (BRONCKART, 1999, 2003; SCHNEUWLY, 2004; DOLZ e SCHNEUWLY, 2004) and Bazerman (2005); and also in presuppositions of Textual Linguistics presented by Charrolles (1988), Van Dijk (1997), Beaugrande and Dressier (1981), Koch and Travaglia (1993, 1995), Koch (2002, 2004) and Val (2000, 2004). We have established as aims to analyze and interpret meaning relations problems in how to articulate direct cited discourse with citing discourse and at the same time explain semantic implications that comes from that articulation that compromise text meaning, at background section in that monographic genre. The analysis, by qualitative and quantitative basis in eleven monographic works that form our corpus, gave us the opportunity to achieve and see that meaning relationships in the articulation of direct cited discourse with citing discourse show problems that may be categorized into three different groups: problems related to meaning relationships with citing discourse that comes before it, problems of meaning relationships with citing discourse that comes after it, and problems with of meaning relationships with citing discourse that come before it and at the same time with citing discourse that comes after it (i.e. in relation to both). These analysis also allow us assert that, these problems, just because they occur frequently, they affect the micro level text coherence, and they also compromise the text global meaning. The results show that students at Letras Course, even in the ending process of their course do not show the real domain in relation to some ways of direct cited discourse organization and working, and also how the ideas articulation work in the construction of relations between direct cited discourse and the citing discourse that can turn those students able to produce a text that enhance acceptable patterns

Processos cognitivos que operam na construção da referência: uma análise das produções textuais elaboradas na EaD - UFRN

Beneath the theoretical assumptions of Cognitive Linguistics contemporary, we analyze the cognitive processes underlying the construction of the reference in the text. To do so, we choose as corpus the written textual productions of undergraduates at the Department of Distance Education/UFRN provided in sections of responses of presential evaluation activities and activities in the Moodle virtual ambience. These activities and texts were produced in the discipline of Reading, Interpretation and Textual Production taught in the courses of Chemistry, Physics, Mathematics, Biology and Geography we monitor during the period of 2008.1 to 2010.1. Through the analysis of discursive productions, it was evident that the construction of the reference is made by means of the activation and manipulation of information acquired through our perceptual and social experiences. Thus, we confirm the cognitive assumption that the linguistic clues available in the texts of the activities serve as guides towards cognitive domains that activate the process of building reference

Valores de referência para pressão inspiratória nasal SNIFF na população brasileira

The strength of respiratory muscle are frequently assessed by maximal inspiratory and expiratory pressure, however, the maneuvers to assess PImax and PEmax are difficult for many patients. The sniff nasal inspiratory pressure (SNIP) is a simple and noninvasive technique use to assess inspiratory muscles strength. Reference values have been previous established for SNIP in adults but no previous studies have provided reference values for SNIP in adult Brazilian population. The main objective of this study were propose reference values of SNIP for Brazilian population through establishment of relationship between anthropometric measurements, physical activity profile and SNIP and at the same time compare the values obtained with reference values previously published. We studied 117 subjects (59 male and 58 female) distributed in different age grouped 20-80 years old. The results showed on significant positive relationship between SNIP and height and negative correlation with age (p<0.05). In the multiple linear regression analysis only age continued to have an independent predictive role for the two dependent variables that correlated with SNIP. The values of SNIP found in Brazilian population were higher when compared with predict values of previous studies. The results of this study provide reference equations of SNIP for health Brazilian population from 20 to 80 years old

Estudo termoanalítico de medicamentos de referência, genérico e similar

This study aimed to apply, thermogravimetriy /derivative Thermogravimetriy (TG/DTG), differential scanning calorimetry (DSC), Differential Thermal Analysis (DTA), to conduct a comparative study on drug reference, generic and whose active principles are similar captopril hydrochlorothiazide, ampicillin, paracetamol, aspirin and mebendazole sold in local pharmacies. Samples of the active ingredients and dosage forms were also characterized by absorption infrared spectroscopy (IR), X-ray diffraction (XRD) and microscopy scanning electron (SEM). The TG / DTG curves showed a general similarity in the thermal behavior of the samples, but also showed the influence of excipients on the thermal stability. The DSC curve of the generic base hydrochlorothiazide showed no peak on the fusion of the drug due to interference of lactose as a diluent, which causes interaction with the active principle causing their degradation before the merger. The DSC curves of the drugs consisting of paracetamol showed reproducibility at the melting point of the active and the other thermal events. The DSC result of binary mixtures involving captopril / magnesium stearate and mebendazole/magnesium stearate showed possible interactions or incompatibilities evidenced by the displacement of the melting point of both drugs. The other mixtures showed no change. The infrared spectra presented were very similar, indicating the presence of functional groups characteristic of the constituents of the samples. The X-ray diffraction showed peaks indicative of crystalline structure of the active ingredients as well as some of the ingredients in the formulation of the drug and the micrographs indicate a general heterogeneity in the size distribution of particles in the samples

Extensão universitária: concepções e ações na UFRN sob a temática direitos humanos e justiça no período 2008 a 2010

This paper concerns a study on the University Extension, by reference to the research extension activities under the theme human rights and justice, developed in the period 2008 to 2010 in UFRN. To do so, it tried to learn the concepts of extension in Brazil from the 1970s until the 2000s in contemporary times. This study considered the neoliberal social context of the University, dominated by educational policies focusing on the hegemony of liberal ideas about society, reflecting the great advances of capital on the organization of workers in the last decades and intensified in the 1990s. This research was guided by two great motivations: the opportunity to apprehend a way to enforce the commitment of public institutions of higher education to the disadvantaged sections of society and what role the university extension space plays as a socially committed public university. The general aim of this study is to identify inside the university extension education what does it mean for practitioners and extension activities and what results it produces to society and to the academic training of future professional citizens in the current neoliberal context. The research has been developed from an analytical and critical approach based on quantitative and qualitative data, using observation techniques and semi-structured interviews. We sought to investigate and understand the social reality, the main object of this work, with an interest in identifying the need for a new teaching/learning process and for a new university practice, in order to effectively improve an advanced academic formation. For this, some interviews have been conducted with teachers, students and the external community involved in extension actions in the period defined by the work, i.e., from 2008 to 2010. In this stage, it was observed that the academic work of university extension is essential to civic education. It was recognized too as a privileged space where university fulfills its social commitment towards society, as long as it joins scientific and popular knowledge having in view a new science and a new social order

Violência contra a mulher:uma análise do trabalho do Centro de Referência da Assistência Social-CREAS/Parnamirim-RN.

This work demonstrates the results obtained from research on violence against women: an analysis of the work from reference center of the Social Assistance-CREAS, held in the city of Parnamirim/RN from September 2008 extending through the february of 2009. Having as goal to investigate and examine in a longitudinal cut, which specifically covers the period from 2006 to 2007, find out extent the actions taken by the Reference Center Specialized Social Assistance- CREAS, contributed to the change of women who were there, by checking if there was any change in their positions ahead of the violence and if they began to realize how social subjects, able to control their living conditions and interfere in the orientation of social dynamics Have a particular emphasis on the presence of work and schooling or lack of them is also a factor to be allied to the barriers and rules imposed on women in contemporary society. In this study it was found through a qualitative research guided by dialectical and implemented through the use of documentary research, observation, semi-structured interview and an extensive theoretical background on the subject in question that the woman victim of violence is in a complex and contradictory context where there is both the construction and deconstruction of rights, a view that there are strong influences of patriarchal culture and the consequences of social issues that specifically searched for the public, focuses on social, economic , political, social and cultural. In this sense, the National Policy to Combat Violence against Women, operated by CREASE Parnamirim, is also reflected in its early stages in the life of these women are to nurture a real chance for these victims of violence, to perceive themselves as social subjects can control their lives and interfere in their own destinies. We want this study to add more knowledge to help and most appropriate intervention in this reality, but without the intention of reaching exhaustion, but to subsidize future studies on the topic of women victims of violence

Violência contra a mulher: uma análise do trabalho do centro de referência da assistência social-CREAS/Parnamirim

This work demonstrates the results obtained from research on violence against women: an analysis of the work from reference center of the Social Assistance-CREAS, held in the city of Parnamirim/RN from September 2008 extending through the february of 2009. Having as goal to investigate and examine in a longitudinal cut, which specifically covers the period from 2006 to 2007, find out extent the actions taken by the Reference Center Specialized Social Assistance-CREAS, contributed to the change of women who were there, by checking if there was any change in their positions ahead of the violence and if they began to realize how social subjects, able to control their living conditions and interfere in the orientation of social dynamics Have a particular emphasis on the presence of work and schooling or lack of them is also a factor to be allied to the barriers and rules imposed on women in contemporary society. In this study it was found through a qualitative research guided by dialectical and implemented through the use of documentary research, observation, semi-structured interview and an extensive theoretical background on the subject in question that the woman victim of violence is in a complex and contradictory context where there is both the construction and deconstruction of rights, a view that there are strong influences of patriarchal culture and the consequences of social issues that specifically searched for the public, focuses on social, economic , political, social and cultural. In this sense, the National Policy to Combat Violence against Women, operated by CREASE Parnamirim, is also reflected in its early stages in the life of these women are to nurture a real chance for these victims of violence, to perceive themselves as social subjects can control their lives and interfere in their own destinies. We want this study to add more knowledge to help and most appropriate intervention in this reality, but without the intention of reaching exhaustion, but to subsidize future studies on the topic of women victims of violence

Uma arquitetura de referência para o desenvolvimento de sistemas interativos multiplataformas

It is increasingly common use of a single computer system using different devices - personal computers, telephones cellular and others - and software platforms - systems graphical user interfaces, Web and other systems. Depending on the technologies involved, different software architectures may be employed. For example, in Web systems, it utilizes architecture client-server - usually extended in three layers. In systems with graphical interfaces, it is common architecture with the style MVC. The use of architectures with different styles hinders the interoperability of systems with multiple platforms. Another aggravating is that often the user interface in each of the devices have structure, appearance and behaviour different on each device, which leads to a low usability. Finally, the user interfaces specific to each of the devices involved, with distinct features and technologies is a job that needs to be done individually and not allow scalability. This study sought to address some of these problems by presenting a reference architecture platform-independent and that allows the user interface can be built from an abstract specification described in the language in the specification of the user interface, the MML. This solution is designed to offer greater interoperability between different platforms, greater consistency between the user interfaces and greater flexibility and scalability for the incorporation of new devices

AO-OIL: um middleware orientado a aspectos baseado em uma arquitetura de referência

Middleware platforms have been widely used as an underlying infrastructure to the development of distributed applications. They provide distribution and heterogeneity transparency and a set of services that ease the construction of distributed applications. Nowadays, the middlewares accommodate an increasing variety of requirements to satisfy distinct application domains. This broad range of application requirements increases the complexity of the middleware, due to the introduction of many cross-cutting concerns in the architecture, which are not properly modularized by traditional programming techniques, resulting in a tangling and spread of theses concerns in the middleware code. The presence of these cross-cutting concerns limits the middleware scalability and aspect-oriented paradigm has been used successfully to improve the modularity, extensibility and customization capabilities of middleware. This work presents AO-OiL, an aspect-oriented (AO) middleware architecture, based on the AO middleware reference architecture. This middleware follows the philosophy that the middleware functionalities must be driven by the application requirements. AO-OiL consists in an AO refactoring of the OiL (Orb in Lua) middleware in order to separate basic and crosscutting concerns. The proposed architecture was implemented in Lua and RE-AspectLua. To evaluate the refactoring impact in the middleware architecture, this paper presents a comparative analysis of performance between AO-OiL and OiL

Controlador adaptativo por modelo de referência e estrutura variável aplicado ao controle de ângulo de carga e fluxo de campo de um gerador síncrono

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