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

Controle adaptativo por modelo de referencia e estrutura variável discreto no tempo

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

Controle on-line para o número de não-conformidades em um ítem inspecionado

The on-line processes control for attributes consists of inspecting a single item at every m produced ones. If the examined item is conforming, the production continues; otherwise, the process stops for adjustment. However, in many practical situations, the interest consist of monitoring the number of non-conformities among the examined items. In this case, if the number of non-conformities is higher than an upper control limit, the process needs to be stopped and some adjustment is required. The contribution of this paper is to propose a control system for the number of nonconforming of the inspected item. Employing properties of an ergodic Markov chain, an expression for the expected cost per item of the control system was obtained and it will be minimized by two parameters: the sampling interval and the upper limit control of the non-conformities of the examined item. Numerical examples illustrate the proposed procedure

Ajuste preventivo versus ajuste corretivo no controle on-line de processo do número de não-conformidades num item inspecionado

In production lines, the entire process is bound to unexpected happenings which may cost losing the production quality. Thus, it means losses to the manufacturer. Identify such causes and remove them is the task of the processing management. The on-line control system consists of periodic inspection of every month produced item. Once any of those items is quali ed as not t, it is admitted that a change in the fraction of the items occurred, and then the process is stopped for adjustments. This work is an extension of Quinino & Ho (2010) and has as objective main to make the monitoramento in a process through the control on-line of quality for the number of non-conformities about the inspected item. The strategy of decision to verify if the process is under control, is directly associated to the limits of the graphic control of non-conformities of the process. A policy of preventive adjustments is incorporated in order to enlarge the conforming fraction of the process. With the help of the R software, a sensibility analysis of the proposed model is done showing in which situations it is most interesting to execute the preventive adjustment

Grafico misto de controle da media com amostragem em dois estagios

This paper proposes a new control chart to monitor a process mean employing a combined npx-X control chart. Basically the procedure consists of splitting the sample of size n into two sub-samples n1 and n2 determined by an optimization search. The sampling occur in two-stages. In the first stage the units of the sub-sample n1 are evaluated by attributes and plotted in npx control chart. If this chart signs then units of second sub-sample are measured and the monitored statistic plotted in X control chart (second stage). If both control charts sign then the process is stopped for adjustment. The possibility of non-inspection in all n items may promote a reduction not only in the cost but also the time spent to examine the sampled items. Performances of the current proposal, individual X and npx control charts are compared. In this study the proposed procedure presents many competitive options for the X control chart for a sample size n and a shift from the target mean. The average time to sign (ATS) of the current proposal lower than the values calculated from an individual X control chart points out that the combined control chart is an efficient tool in monitoring process mean.

Caracterização hidrodinâmica e morfo-sedimentar do estuário Potengi e áreas adjascentes: subsídios para controle e recuperação ambiental no caso de derrames de hidrocarboneto

This study presents the Environmental Sensibility Mapping to oil spillings on the Potengi estuary - RN and neighboring coastline through remote sensing data, collecting, treatment and integration of the geomorphologic, oceanographic (temperature, salinity, density, direction and intensity), meteorological (wind speed and direction) and high resolution seismic (bathymetry and sonography) data. The Potengi river estuary is located on the eastern coastline of the Rio Grande do Norte State, being inserted in the geological context for the coastal Pernambuco-Paraíba basin and spreading over 18 km; it shelters the Natal harbor zone and an oil terminal, centralizing, therefore, important oil transport operations that can cause accidental spillings. Under the oceanographic point of view, the Potengi estuary is characterized by the absence of any expressive thermic stratification, being classified as partially mixed, B type according to Pritchard (1955), and 2 type in conformity to the stratification-circulation diagram by Hansen & Rattray (1966). Two main wind systems are responsable for the formation of wave sets that occur in the area. The dynamic tide presents, in the Natal Harbor, mean amplitude in spring and quadrature tides, with around 2.8 and 2m, respectively. The mechanism of saline tide mixing was defined through the salinity which is the main parameter for the identification of this mechanism. Important variations of the salinity mean values (36.32 psu), temperature (28.11ºC) and density (22.96 kg/m3) in the estuarine waters presented features belonging to low latitude regions. The water temperature follows the air temperature variations, in the region, with expressive daily amplitudes. In this study, the identification of the estuarine bed morphology through bathymetric and sonographic analysis, had the purpose to evaluate the influence of the superficial and bottom currents for the bottom shaping. In this way, the use of the side scan sonar showed, to be very useful in the identification of the bottom morphology and its relationship with the predominant action of the tidal currents in the Potengi estuary. Besides, it showed how the sonograms can be a support to the comparison of the several patterns derived from the local hydrodynamic variations. The holocene sediments, which fill the estuarine channel, are predominantly sandy, varying from selected, sometimes silty. The sedimentation is controlled by the environmental hydrodynamic conditions, being recognized two important textural facies: Muddy Facies and Sandy Facies. The distribution of these textural facies apparently oscillates owing to the tidal cycle and flow intensity. Each one of the above mentioned data was integrated in a Geographic Information System (GIS), from which was produced the Environmental Sensibility Map to oil spillings with Coastal Sensibility Index (CSI) to the Potengi estuary. The integrated analysis of these data is essential to oil spilling contingency plans, in order to reduce the spilling environmental consequences and to make efficient the endeavours of contention and cleaning up/removal on the Natal Harbor. This study has the aim to collaborate for the increase of informations about the estuarine environment and contribute to a better management of the question: environment/polluting loads

Dois testes de imageamento com GPR em problemas de controle ambiental em regiões tropicais: migração de dunas e localização de dutos de óleo enterrados

Because the penetration depth of Ground Penetrating Radar (GPR) signals is very limited in high conductive soils, the usefullness of this method in tropical regions is not yet completly known. The main objective of this researh is to test the usefullness of the method in Brazil. Two typical problems where GPR has been used in Europe and North American were choosed for this test: the first one is to characterize the internal structures of a sand body and the second problem is the localization of old buried pipes lines. The first test was done near the city of São Bento do Norte, in the northern coast of Rio Grande do Norte state, NE Brazil. In this region, there is a sand dune that is migrating very fast in the direction of adjacent settling areas. To characterize the internal structure of the dune and its relationship to the prevailing wind direction, as a preliminary step to understand the dune migration, GPR profiles using the 400 MHz frequency were performed in E-W, N-S, NE-SW, and SE-NW directions over the sand dune intersecting at the top of the dune. The practical resolution of the GPR data is around 30 cm; this was sufficient to distinguish individual foresets inside the dune. After applying the elevation correction to the data, we identified that dips of bedding structures are smallest for the N-S profile, which is perpendicular to the dominant wind direction, largest for the E-W profile, and intermediate for the SW-NE and SE-NW profiles. Foresets in the E-W profile dip with angles varying from 2 to 6 degrees. In the E-W profile, the water table and a horizontal truncation interface separating two generations of dunes were identified, as well as an abrupt directional change in the foreset patterns associated to a lateral contact between two dune generations, the older one extending to the west. The used high frequency of 400 Mhz does not allow a penetration deep enough to map completely these internal contacts. The second test was done near Estreito, a small town near Carnaúbais city, also in Rio Grande do Norte state. In this locality, there are several old pipe lines buried in area covered by plantations where digging should be minimized. Several GPR profiles using the 400 and 200 MHz frequency were performed trying to intercept perpendicularly the possible pipe lines. Because of the high conductivity of the soil, the raw original data can hardly be use to identify the pipe lines. However, after an adequate processing over the 200 MHz profiles, six pipe lines were identified. As a global result of the tests, GPR can be very usefull if the conductivity of the ground is low or, in the case of medium conductivities of the soils, if adequate processing is performed

Monitoramento costeiro das praias de São Bento do Norte e Caiçara do Norte RN: implicações para o pólo petrolífero de Guamaré

This dissertation the results of a research developed in the area of São Bento do Norte and Caiçara do Norte, northern coast of the State of Rio Grande do Norte, during the period of June of 2000 to August of 2001, in the ambit of the projects MAMBMARÉ (CNPq/CTPETRO) and PROBRAL (CAPES/DAAD).The objective principal of this research was the characterization of the sedimentary dynamics of this coast, with base in data of coastal process (winds, currents, waves and tides), with topographical risings (beach profiles and dunes), satellite images and sedimentary analyses. The more specific objectives were accomplished the coastal monitoring of this coast, to verify the maintenance of an erosive tendency or progradacional after the groynes construction for contention of the erosion in the beach of Caiçara do Norte, as well as to verify the influence of the features of bottom of the platform interns adjacent on the pole petroliferous of Guamaré. The executed monitoramento allowed to identify that the movement of the sediments, along the year, in that area, is cyclical, reaching the largest oscillations during the months of winter (deposition) and they will summer (erosion). The sedimentologic studies indicated a general tendency for sands quartzosas, with gravel presence, moderately to good selected, with asymmetry predominantly negative. In agreement with the parameter of Dean (1957), used in the identification of the state morfodinâmico of the beaches, monitored beaches, are basically reflectivas with tendency to middlemen, what frames that space of the coast norteriograndense, as a space strongly vulnerable to erosive processes. The studies developed in the platform, it interns of this area, allowed to visualize for the first time, in large scale, the distribution of the features of the submarine bottom to the batométrico coat of 25 meters. Being pointed out the presence of a high one topographical submerged, with about 5 meters of height, 1 km of width and more than 24 meters of extension, located in the platform it interns in front of São Bento do Norte; coincident with the trend of the system of flaws of Carnaubais. This feature relay an important paper on the control of the sedimentary processes and oceanographic, as well as in the coastal evolution of this area of the RN state, and they affect the area of the pole petroliferous of Guamaré directly. These results contribute to a better knowledge of the processes in the area, and consequently as subsidies implantation of measures of coastal and environmental protection for the cities of São Bento do Norte and Caiçara do Norte, as well as to understand how the geological-sedimentary processes and oceanographic, in this area, are influencing the characteristics geoambientais of the pole petroliferous of Guamaré

A reafirmação do bairro:um estudo geo-histórico do bairro do Alecrim na cidade de Natal-RN

By the end of the 21st Century, economy globalization trends to show a velocity process through which market being expanded characterized by an intense going on of the internationalization of finance, after that marginalizing the periphery of the social spaces. It is clear to see that this process occurred in those less developed countries happens in an accentuated way just because income distribution that is so regressive and also because the insufficient enclosing of the social programs, we find this situation in a big part of Brazilian cities. The marginalizing social economical process observed in Natal, a city located in the east coast part of Northeast region in Brazil and that owns a population upper to 778 thousand in habitants is nearly linked to the extension of goods and services commerce. The installation of new urban activities in the city pointed out tourist activity as the greater impulsive thing in the phenomenon promotion, most of them aiming to promote Natal to the national and international scenery. It privilege strongly in the South zone with economical implementations such as shopping s centers, supermarkets, and home buildings condominiums leading to a loss of functionality of some traditional district located in central areas of the city. Notwithstanding, some spaces, for instance Alecrim district officially created in 1911, has notably resisted to the expansion of the urban process pointed out in Natal in the last years. So that this put Alecrim District as a district with originally characteristics reaffirmed along the historical process form old times. The predominance of some residential characteristics such as the incidence of some villages and a concentration of a big and confuse popular commerce distributed along streets puts Alecrim District as a resistant space in Natal. The same way analyze Alecrim District under the prism of Historic Geography because we understand this way it accomplishes a fundamental role in the theoretical methodological development of our work, just when we analyze the time as a variant in our object of study. It is still inside this theoretical field that we carry out a brief reviewing about quarter/district definition, under the optic from several registered and scientific resources taken into account along this work, because we understand that it was necessary to think this important spatial unit especially to know exactly what we are referring to as a district and so we can reaffirm Alecrim as an important and traditional district to Natal and it has been resisting to spatial transformation verified in the last years in Natal city. To give support to our reflection we used methodological tools related to inhabitants lifestyles knowledge and also the study of Alecrim District as a space that promote a certain centrality in Natal as some indicators to keep original characteristics in the district in Natal

Cidades pequenas, grandes problemas :perfil urbano do Agreste Potiguar

In view of the diversity and the heterogeneity of the existing cities in Brazil, our approach refers to the urban and non-metropolitan areas. Aiming to foment the studies on small cities e to apprehend the sociospatial configuration of the urban environment in such cities, this piece of work elaborates and analyzes the urban profile of the small cities of the Agreste Potiguar region, using as a theoretical reference landmark the production of the urban and regional space, from the decade of 1970 to 2000. Starting from this reference, this piece of work presents an urban sociospatial characterization of the small cities of the Agreste Potiguar region, with emphasis on the economic framework, on the population dynamics, on the main social data, culminating in the main characteristics of the local daily life. The study of the small cities of the Agreste Potiguar region makes it possible the comprehension of the problems that involve the cities of this size, above all, those inserted in economically fragile regions. In the analyzed period, the changes occurred in the productive structure of the State of Rio Grande do Norte triggered a great crisis in the economy of the Agreste Potiguar region. This aspect, allied to the insufficient performance of the public power, contributed to the sprouting of some sociospatial problems, amongst which may be distinguished: the economic fragility, the generalized unemployment, the lack of security and the urban infrastructure absence sufficient to take care of the social demand. Even facing the existing problems, the small cities must be seen as potential spaces, capable to promote the regional development. To do so, it is necessary a process of democratization of the public administration, an ample popular participation and the establishment of a new urban policy, that aims at the social promotion of the individuals, the guarantee of basic necessities and the access to the necessary services to a dignified life

A dinâmica territorial da Assembléia de Deus do seridó do Rio Grande do Norte

In the norte-rio-grandense backwoods is possible to join to the power forms both political and economical ones, religious groups keeping under your control areas, people and flow of them, as well as settling new places of acts. That control refers to a field of power delimited by space, in other words, it refers to a territory marked and planned to reproductive intentions on the space. In relation to the religious pluralism, the Assembly of God church, in your territorial dynamics, has been standing out by the strategies of delimitation and space increase which by a constant territorial division process (1943-2010) managed to widen material and symbolic scale of its power for all cities of the Rio Grande do Norte backwoods. The Assembly of God church as the greatest Pentecostal denomination of Brazil was formed in the Rio Grande do Norte Seridó, following a ecclesiastical and governmental model divided into three ecclesiastical fields hosted in those following cities: Caicó, Currais Novos and Parelhas. Those headquarters interlink a limited number of churches through normative codes, which they express a functional dimension (bureaucratic) and in another symbolic one (charismatic) in an only field of territorial control. In this manner, the maintenance of the territorial power in the Assembly of God church is done by a charismatic-bureaucratic administration, expressed in the interdependent of material and abstract mechanisms. The believers permanent contact toward those mechanisms of institutional control revealed territorial identities which causes a feeling of property of the believer as much to the Pentecostal belief system as to community of the Assembly of God church. Considering new possibilities of articulation of the Rio Grande do Norte backwoods towards others territories more multiple, culturally, noticed cultural adjustments and revaluation at themselves. In relation to the territory of the Assembly of God church this one has exposed itself defensive faced with that cultural hybridization tendency, resisting a closer dialogue to new symbolic elements, mainly those came from the multifaceted neo-pentecostal movement. Unlike more open and flexible churches towards others significant systems, The Assembly of God church tries to reinforce the boundaries of its territory considering by the orthodoxy of its routine and customs

A Produção do espaço das pequenas cidades do Seridó Potiguar

The present research wants to comprehend the small towns process of production situated in the Seridó Potiguar, under a historical perspective. Many were the ways passedthrough and the social agents involved in the organization of this space that is build in the treefold: cattle-breeding/cotton plantation/mining, giving origin to the firstcenters. Through the analysis of demographic, economical and social aspects we elaborate a small towns urban profile, considering the 80 s period until today. Those aspects reveal a town s systems with several characteristics and impossible to be insert in some table of reference. These elements are showed in the concentration of urban equipment in the distribution of economical opportunities and in the social connection that are made in the routine of each place. However, the analysis of production s process and special organization proportinated us an explanation of small towns reality, confirming its importance in the urban system, catching sight that, although the restrict urban functions presented, it confirms its towns character by organizing andadministratingthe life specific community

Vende-se uma vila: análise intra-urbana das vilas na Vila de Ponta Negra e no bairro de Nova Descoberta - Zona Sul de Natal

This dissertation is about low-income rental housing vilas in the South Zone in the city of Natal. Vilas are a string of houses, built privately in an urban plot of land, usually a backyard, facing a narrow street beco. This type of housing is originated in the 19th century in the Brazilian scenario. In Natal, this has become more popular since the late 1960s. This study is aimed at analyzing the urban integration of the vilas, considering that these house a low income population, vis à vis the speedy development of Natal s most economically dynamic area. The study starts with a discussion of the production of space, taking into consideration categories such as use value, exchange value, commodity and land rent. Field work was undertaken through structured interviews with dwellers of vilas in Nova Descoberta and Ponta Negra neighbourhoods. Owners of vilas were also interviewed. Data collected indicated worrisome housing conditions. Vilas, in the areas researched, are increasingly becoming unwelcome, constituting guetos in a place where landscape is changing rapidly. Gentrification is fast under way, first because of rise in rent and taxes; second because of general rise in living costs

Zoneamento ambiental do Município de Aquiraz-CE

The Metropolitan Region of Fortaleza (RMF) is composed by thirteen cities, where is call the attention of Aquiraz. The city has a excellent resort area and a big importance in socioculture and historics aspects. It was one of the first village of Ceará, and it was founded in 1699, with was also the capital of the state until 1726. The urban local development has been disorganized in the last decades, the fact is, insert of turismon in its coast, and it is unable with alow capacity of the natural suppots, configuring unsustainable and et environment ambience. Considering as a turistic region, it is preoccupy, been necessart to create a better control of the nature of the region by the users. The environmental zoning in this work it is to plan of adequate form the use of the ground based in the management of the interests and the social and economic necessities in accord with the preservation of the environment and the natural characteristics of the city. The same is one great instrument planning where use to be analized in differents ways: social, ambiental, economical and institucional, and promove alternatives of use and occupation of the land to recreate the city. The methodo used to get the real objective, englobed zonal maps in ambiental unities and others themes (geologic/geomorphologic) since than the images from satelities LANDSAT and SPOT and fotografies under position of maps, secundaries listes gets in publics department, bibliographie, informations by the local populations. This prociduries mede easy to create maps, geologic/geomorphologic, of use and occupation the earth and the environmental zoning to analize the dynamic and the working of each ambiental unity of the city Aquiraz wich is located by map of this job. As a result of this job was confectionated the environmental zoning map of Aquiraz wich was divided in five ambiental unities and restrictions areas of occupation: unit I Littoral Plain (zoning with serious restrictions to the occupation); unit II Sub-Littoral Plain (improper zoning to the occupation); unit III between tray zoning Pré-Littoral and Peripheral Depression (improper zoning to the occupation); unit IV Strativism reserve of the plug (zoning used more under control in its occupation) and unit V Fluvial Plain Localities of the Indians Jenipapo-Kaninde/ locality Quilombolas (zoning used more without official regulation). With proposal in the ambient units above one expects that it has a reduction of the ambient degradation and protection of the local biodiversity of the city of Aquiraz in the State of the Ceará

Sistema de conversão de energia eólica baseado no gerador de indução duplamente alimentado: análise e contribuição ao controle da máquina

The humanity reached a time of unprecedented technological development. Science has achieved and continues to achieve technologies that allowed increasingly to understand the universe and the laws which govern it, and also try to coexist without destroying the planet we live on. One of the main challenges of the XXI century is to seek and increase new sources of clean energy, renewable and able to sustain our growth and lifestyle. It is the duty of every researcher engage and contribute in this race of energy. In this context, wind power presents itself as one of the great promises for the future of electricity generation . Despite being a bit older than other sources of renewable energy, wind power still presents a wide field for improvement. The development of new techniques for control of the generator along with the development of research laboratories specializing in wind generation are one of the key points to improve the performance, efficiency and reliability of the system. Appropriate control of back-to-back converter scheme allows wind turbines based on the doubly-fed induction generator to operate in the variable-speed mode, whose benefits include maximum power extraction, reactive power injection and mechanical stress reduction. The generator-side converter provides control of active and reactive power injected into the grid, whereas the grid-side converter provides control of the DC link voltage and bi-directional power flow. The conventional control structure uses PI controllers with feed-forward compensation of cross-coupling dq terms. This control technique is sensitive to model uncertainties and the compensation of dynamic dq terms results on a competing control strategy. Therefore, to overcome these problems, it is proposed in this thesis a robust internal model based state-feedback control structure in order to eliminate the cross-coupling terms and thereby improve the generator drive as well as its dynamic behavior during sudden changes in wind speed. It is compared the conventional control approach with the proposed control technique for DFIG wind turbine control under both steady and gust wind conditions. Moreover, it is also proposed in this thesis an wind turbine emulator, which was developed to recreate in laboratory a realistic condition and to submit the generator to several wind speed conditions.