Controle feedback de nível baseado em sensor de imagem aplicado ao equipamento misturador-decantador à inversão de fases (MDIF®)

The treatment of wastewaters contaminated with oil is of great practical interest and it is fundamental in environmental issues. A relevant process, which has been studied on continuous treatment of contaminated water with oil, is the equipment denominated MDIF® (a mixer-settler based on phase inversion). An important variable during the operation of MDIF® is the water-solvent interface level in the separation section. The control of this level is essential both to avoid the dragging of the solvent during the water removal and improve the extraction efficiency of the oil by the solvent. The measurement of oil-water interface level (in line) is still a hard task. There are few sensors able to measure oil-water interface level in a reliable way. In the case of lab scale systems, there are no interface sensors with compatible dimensions. The objective of this work was to implement a level control system to the organic solvent/water interface level on the equipment MDIF®. The detection of the interface level is based on the acquisition and treatment of images obtained dynamically through a standard camera (webcam). The control strategy was developed to operate in feedback mode, where the level measure obtained by image detection is compared to the desired level and an action is taken on a control valve according to an implemented PID law. A control and data acquisition program was developed in Fortran to accomplish the following tasks: image acquisition; water-solvent interface identification; to perform decisions and send control signals; and to record data in files. Some experimental runs in open-loop were carried out using the MDIF® and random pulse disturbances were applied on the input variable (water outlet flow). The responses of interface level permitted the process identification by transfer models. From these models, the parameters for a PID controller were tuned by direct synthesis and tests in closed-loop were performed. Preliminary results for the feedback loop demonstrated that the sensor and the control strategy developed in this work were suitable for the control of organic solvent-water interface level

Identificação e comparação entre controle preditivo com modelo não linear e PI sintonizados com PSO em sistema de separação gravitacional de águia-óleo

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

Modelagem e controle de um microveículo aéreo: uma aplicação de estabilidade robusta com a técnica backstepping em uma estrutura hexarrotor

In this Thesis, the development of the dynamic model of multirotor unmanned aerial vehicle with vertical takeoff and landing characteristics, considering input nonlinearities and a full state robust backstepping controller are presented. The dynamic model is expressed using the Newton-Euler laws, aiming to obtain a better mathematical representation of the mechanical system for system analysis and control design, not only when it is hovering, but also when it is taking-off, or landing, or flying to perform a task. The input nonlinearities are the deadzone and saturation, where the gravitational effect and the inherent physical constrains of the rotors are related and addressed. The experimental multirotor aerial vehicle is equipped with an inertial measurement unit and a sonar sensor, which appropriately provides measurements of attitude and altitude. A real-time attitude estimation scheme based on the extended Kalman filter using quaternions was developed. Then, for robustness analysis, sensors were modeled as the ideal value with addition of an unknown bias and unknown white noise. The bounded robust attitude/altitude controller were derived based on globally uniformly practically asymptotically stable for real systems, that remains globally uniformly asymptotically stable if and only if their solutions are globally uniformly bounded, dealing with convergence and stability into a ball of the state space with non-null radius, under some assumptions. The Lyapunov analysis technique was used to prove the stability of the closed-loop system, compute bounds on control gains and guaranteeing desired bounds on attitude dynamics tracking errors in the presence of measurement disturbances. The controller laws were tested in numerical simulations and in an experimental hexarotor, developed at the UFRN Robotics Laboratory

Integridade da pele em idosos: revisão da literatura segundo as cartas de promoção da saúde

Trata-se de uma revisão bibliográfica que objetivou relacionar as medidas educativas para a promoção da integridade da pele em idosos com as Cartas de Promoção da Saúde. Realizou-se a busca nas bases de dados CINAHL, SCOPUS, LILACS e COCHRANE, nos portais CAPES e BVS e na biblioteca PUBMED, mediante a aplicação dos descritores Health Education; Skin e Aged. Os resultados dos 7 artigos analisados apontaram como principais medidas educativas: inspeção diária da pele, cuidados com calçados e com os pés, uso regular de protetor solar e mudanças de decúbito. Essas medidas estavam relacionadas com as seguintes Cartas de Promoção da Saúde: Ottawa, Declaração de Santafé de Bogotá e Declaração de Jacarta. Conclui-se que as medidas educativas, baseadas nas Cartas, são de grande relevância para a criação de uma cultura de saúde, com enfoque na população e no indivíduo como agentes executores imprescindíveis para o alcance da promoção da saúde

Comportamento do consumidor: um estudo do mercado imobiliário em condomínios verticais fechados na região metropolitana de Natal

The research in question looked for to establish the relation between the motivation (of the proprietor of apartment) to change itself of another one apartment, in closed vertical condominium (residential mobility) in the period of the recognition of the necessity, and the satisfaction with the apartment after consume. The universe or the population chosen for the development of the study was of proprietors of apartment in vertical condominiums located in the region metropolitan of Natal. The analysis of data was made using the techniques of linear regression and logistic regression between variables. The linear regression found relations between the motivations for housing change and the satisfaction in after consume with some attributes of the apartment. The logistic regression showed that relations between the motivations for change and the general satisfaction to the apartment exist as a whole, in the period after consumes. With regard to the motivation to change itself of a apartment for another one, some reasons shown more motivation them the others. The research found different degrees of satisfaction with certain characteristics of the apartment and degrees of no satisfaction with others. Finally the results of the research had contributed for the reply of the problem that guided the present study, therefore had obtained in such a way to find how much logistic not linear relations between the two periods purchase (recognition of the necessity and evaluation after consume) and had elucidated the process that goes since the choice the product until the satisfaction of the necessities

Contribuições à análise de robustez de sistemas de controle usando redes neurais

This work develops a robustness analysis with respect to the modeling errors, being applied to the strategies of indirect control using Artificial Neural Networks - ANN s, belong to the multilayer feedforward perceptron class with on-line training based on gradient method (backpropagation). The presented schemes are called Indirect Hybrid Control and Indirect Neural Control. They are presented two Robustness Theorems, being one for each proposed indirect control scheme, which allow the computation of the maximum steady-state control error that will occur due to the modeling error what is caused by the neural identifier, either for the closed loop configuration having a conventional controller - Indirect Hybrid Control, or for the closed loop configuration having a neural controller - Indirect Neural Control. Considering that the robustness analysis is restrict only to the steady-state plant behavior, this work also includes a stability analysis transcription that is suitable for multilayer perceptron class of ANN s trained with backpropagation algorithm, to assure the convergence and stability of the used neural systems. By other side, the boundness of the initial transient behavior is assured by the assumption that the plant is BIBO (Bounded Input, Bounded Output) stable. The Robustness Theorems were tested on the proposed indirect control strategies, while applied to regulation control of simulated examples using nonlinear plants, and its results are presented

Controle de Manipulador Redundante Utilizando Realimentação Visual

In conventional robot manipulator control, the desired path is specified in cartesian space and converted to joint space through inverse kinematics mapping. The joint references generated by this mapping are utilized for dynamic control in joint space. Thus, the end-effector position is, in fact, controlled indirectly, in open-loop, and the accuracy of grip position control directly depends on the accuracy of the available kinematic model. In this report, a new scheme for redundant manipulator kinematic control, based on visual servoing is proposed. In the proposed system, a robot image acquired through a CCD camera is processed in order to compute the position and orientation of each link of the robot arm. The robot task is specified as a temporal sequence of reference images of the robot arm. Thus, both the measured pose and the reference pose are specified in the same image space, and its difference is utilized to generate a cartesian space error for kinematic control purposes. The proposed control scheme was applied in a four degree-of-freedom planar redundant robot arm, experimental results are shown

Códigos de sustentação da linguagem no cotidiano prisional do Rio Grande do Norte: penitenciária estadual de Parnamirim

The quarrel, in this study, tells about the language as social practical in the daily of Parnamirim State Prison that is integrated to the Rio Grande do Norte Penitentiary System - SISPERN, destined for men in fulfilment of penalty privative of freedom, in closed regimen. For the accomplishment of the research, the delimited objectives had been to analyze the language repertoires created in the prisional daily, trying to identify how it´s turned into distinct forms of resistance to the mechanisms of control in penitentiary system; to investigate which are the language repertoires created from the new sociability forms developed among prisoners and identify how the language repertoires are expressed in the daily prisional on relations/exercises of power not-institutionalized. In the methodological aspect, the study is in a qualitative boarding, that has as main instrument the interview. The inquiry was possible by means of using instruments for data collection, like as: the direct comment in the prisional daily duly registered as researcher´s ethnographical procedure, the analysis of interns´ cadastre handbooks and the application of half-structuralized interview, to the subjects of the research. The construction and understanding of the study object had been based on authors who argue on the arrest, as: Foucault, Goffman, Carvalho Filho and, in particular was searched the theorical referencial that approaches the language in a social and cultural perspective: Orlandi, Manfred, Bastos and Candiotto, amongst others. Beyond the normative endorsement of the Brazilian legislation, through the Law of Criminal Execution, of the Criminal Code and the Federal Constitution of the country and the legal apparatus in state scope. Still in the research methodological perspective, after the collection the data had been submitted to an analysis of the speech from Foucalt´s theory and in the Orlandi´s perspective, being also qualitative and quantitative. The results had evidenced that the social and juridical profile of the population in the site inquired is not different of others Brazilian prisons, composed for men, in its majority, with age band between 21 and 30 years old, prisoners for practicing crimes against the patrimony, against life, amongst others, and, in special, criminal recidivists. It evidenced, still, that the daily prisional of PSP is characterized for a sociocultural diversity expressed in the relations of power not institutionalized, that contributes for the formation and division of the groups, each one using a set of language codes/ repertoires sustentation. Therefore, the language, in the daily prisional, is one of the ways to understand the singularity of the sociability relations and as social practicing mediated by relations/exercises of power and antagonistic interests, in which each group aims first of all, their own interests. It represents the complexity of the social relations, in the prisional space, with diverse effects, in function of the situation and the moment. The language in the arrest, beyond the communication function, assumes and represents central element for the sociability human being, contributes for its changings and it´s configured as one of the resistance forms of prisoners against the controling, disciplining and monitoring mechanisms of penitentiary system

Integridade da pele em idosos: revisão da literatura segundo as cartas de promoção da saúde

Trata-se de uma revisão bibliográfica que objetivou relacionar as medidas educativas para a promoção da integridade da pele em idosos com as Cartas de Promoção da Saúde. Realizou-se a busca nas bases de dados CINAHL, SCOPUS, LILACS e COCHRANE, nos portais CAPES e BVS e na biblioteca PUBMED, mediante a aplicação dos descritores Health Education; Skin e Aged. Os resultados dos 7 artigos analisados apontaram como principais medidas educativas: inspeção diária da pele, cuidados com calçados e com os pés, uso regular de protetor solar e mudanças de decúbito. Essas medidas estavam relacionadas com as seguintes Cartas de Promoção da Saúde: Ottawa, Declaração de Santafé de Bogotá e Declaração de Jacarta. Conclui-se que as medidas educativas, baseadas nas Cartas, são de grande relevância para a criação de uma cultura de saúde, com enfoque na população e no indivíduo como agentes executores imprescindíveis para o alcance da promoção da saúde

Comportamento do consumidor: um estudo do mercado imobiliário em condomínios verticais fechados na região metropolitana de Natal

The research in question looked for to establish the relation between the motivation (of the proprietor of apartment) to change itself of another one apartment, in closed vertical condominium (residential mobility) in the period of the recognition of the necessity, and the satisfaction with the apartment after consume. The universe or the population chosen for the development of the study was of proprietors of apartment in vertical condominiums located in the region metropolitan of Natal. The analysis of data was made using the techniques of linear regression and logistic regression between variables. The linear regression found relations between the motivations for housing change and the satisfaction in after consume with some attributes of the apartment. The logistic regression showed that relations between the motivations for change and the general satisfaction to the apartment exist as a whole, in the period after consumes. With regard to the motivation to change itself of a apartment for another one, some reasons shown more motivation them the others. The research found different degrees of satisfaction with certain characteristics of the apartment and degrees of no satisfaction with others. Finally the results of the research had contributed for the reply of the problem that guided the present study, therefore had obtained in such a way to find how much logistic not linear relations between the two periods purchase (recognition of the necessity and evaluation after consume) and had elucidated the process that goes since the choice the product until the satisfaction of the necessities