45 resultados para plataformas

em Universidade Federal do Rio Grande do Norte(UFRN)


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In the operational context of industrial processes, alarm, by definition, is a warning to the operator that an action with limited time to run is required, while the event is a change of state information, which does not require action by the operator, therefore should not be advertised, and only stored for analysis of maintenance, incidents and used for signaling / monitoring (EEMUA, 2007). However, alarms and events are often confused and improperly configured similarly by developers of automation systems. This practice results in a high amount of pseudo-alarms during the operation of industrial processes. The high number of alarms is a major obstacle to improving operational efficiency, making it difficult to identify problems and increasing the time to respond to abnormalities. The main consequences of this scenario are the increased risk to personal safety, facilities, environment deterioration and loss of production. The aim of this paper is to present a philosophy for setting up a system of supervision and control, developed with the aim of reducing the amount of pseudo-alarms and increase reliability of the information that the system provides. A real case study was conducted in the automation system of the offshore production of hydrocarbons from Petrobras in Rio Grande do Norte, in order to validate the application of this new methodology. The work followed the premises of the tool presented in ISA SP18.2. 2009, called "life cycle alarm . After the implementation of methodology there was a significant reduction in the number of alarms

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This dissertation describes the use of new Technologies of the Areas of Telecommunications, Networks and Industrial Automation for increase of the Operational Safety and obtaining of Operational Improvements in the Platforms Petroliferous Offshore. The presented solution represents the junction of several modules of these areas, making possible the Supervision and Contrai of the Platforms Petroliferous Offshore starting from an Station Onshore, in way similar to a remote contral, by virtue of the visualization possibility and audition of the operational area through cameras and microphones, looking the operator of the system to be "present" in the platform. This way, it diminishes the embarked people's need, increasing the Operational Safety. As consequence, we have the obtaining of Operational Improvements, by virtue of the use of a digital link of large band it releases multi-service. In this link traffic simultaneously digital signs of data (Ethernet Network), telephony (Phone VoIP), image and sound

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This work intends to analyze the behavior of the gas flow of plunger lift wells producing to well testing separators in offshore production platforms to aim a technical procedure to estimate the gas flow during the slug production period. The motivation for this work appeared from the expectation of some wells equipped with plunger lift method by PETROBRAS in Ubarana sea field located at Rio Grande do Norte State coast where the produced fluids measurement is made in well testing separators at the platform. The oil artificial lift method called plunger lift is used when the available energy of the reservoir is not high enough to overcome all the necessary load losses to lift the oil from the bottom of the well to the surface continuously. This method consists, basically, in one free piston acting as a mechanical interface between the formation gas and the produced liquids, greatly increasing the well s lifting efficiency. A pneumatic control valve is mounted at the flow line to control the cycles. When this valve opens, the plunger starts to move from the bottom to the surface of the well lifting all the oil and gas that are above it until to reach the well test separator where the fluids are measured. The well test separator is used to measure all the volumes produced by the well during a certain period of time called production test. In most cases, the separators are designed to measure stabilized flow, in other words, reasonably constant flow by the use of level and pressure electronic controllers (PLC) and by assumption of a steady pressure inside the separator. With plunger lift wells the liquid and gas flow at the surface are cyclical and unstable what causes the appearance of slugs inside the separator, mainly in the gas phase, because introduce significant errors in the measurement system (e.g.: overrange error). The flow gas analysis proposed in this work is based on two mathematical models used together: i) a plunger lift well model proposed by Baruzzi [1] with later modifications made by Bolonhini [2] to built a plunger lift simulator; ii) a two-phase separator model (gas + liquid) based from a three-phase separator model (gas + oil + water) proposed by Nunes [3]. Based on the models above and with field data collected from the well test separator of PUB-02 platform (Ubarana sea field) it was possible to demonstrate that the output gas flow of the separator can be estimate, with a reasonable precision, from the control signal of the Pressure Control Valve (PCV). Several models of the System Identification Toolbox from MATLAB® were analyzed to evaluate which one better fit to the data collected from the field. For validation of the models, it was used the AIC criterion, as well as a variant of the cross validation criterion. The ARX model performance was the best one to fit to the data and, this way, we decided to evaluate a recursive algorithm (RARX) also with real time data. The results were quite promising that indicating the viability to estimate the output gas flow rate from a plunger lift well producing to a well test separator, with the built-in information of the control signal to the PCV

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The production of oil and gas is usually accompanied by the production of water, also known as produced water. Studies were conducted in platforms that discharge produced water in the Atlantic Ocean due to oil and gas production by Petrobras from 1996 to 2006 in the following basins: Santos (Brazilian south region), Campos (Brazilian southeast region) and Ceara (Brazilian northeast region). This study encompasses chemical composition, toxicological effects, discharge volumes, and produced water behavior after releasing in the ocean, including dispersion plumes modeling and monitoring data of the marine environment. The concentration medians for a sampling of 50 samples were: ammonia (70 mg L-1), boron (1.3 mg L1), iron (7.4 mg L-1), BTEX (4.6 mg L-1), PAH (0.53 mg L-1), TPH (28 mg L-1); phenols (1.3 mg L-1) and radioisotopes (0.15 Bq L-1 for 226Ra and 0.09 Bq L-1 for 228Ra). The concentrations of the organic and inorganic parameters observed for the Brazilian platforms were similar to the international reference data for the produced water in the North Sea and in other regions of the world. It was found significant differences in concentrations of the following parameters: BTEX (p<0.0001), phenols (p=0.0212), boron (p<0.0001), iron (p<0.0001) and toxicological response in sea urchin Lytechinus variegatus (p<0.0001) when considering two distinguished groups, platforms from southeast and northeast Region (PCR-1). Significant differences were not observed among the other parameters. In platforms with large gas production, the monoaromatic concentrations (BTEX from 15.8 to 21.6 mg L-1) and phenols (from 2 to 83 mg L-1) were higher than in oil plataforms (median concentrations of BTEX were 4.6 mg L-1 for n=53, and of phenols were 1.3 mg L-1 for n=46). It was also conducted a study about the influence of dispersion plumes of produced water in the vicinity of six platforms of oil and gas production (P-26, PPG-1, PCR-1, P-32, SS-06), and in a hypothetical critical scenario using the chemical characteristics of each effluent. Through this study, using CORMIX and CHEMMAP models for dispersion plumes simulation of the produced water discharges, it was possible to obtain the dilution dimension in the ocean after those discharges. The dispersion plumes of the produced water modelling in field vicinity showed dilutions of 700 to 900 times for the first 30-40 meters from the platform PCR-1 discharge point; 100 times for the platform P-32, with 30 meters of distance; 150 times for the platform P-26, with 40 meters of distance; 100 times for the platform PPG-1, with 130 meters of distance; 280 to 350 times for the platform SS-06, with 130 meters of distance, 100 times for the hypothetical critical scenario, with the 130 meters of distance. The dilutions continue in the far field, and with the results of the simulations, it was possible to verify that all the parameters presented concentrations bellow the maximum values established by Brazilian legislation for seawater (CONAMA 357/05 - Class 1), before the 500 meters distance of the discharge point. These results were in agreement with the field measurements. Although, in general results for the Brazilian produced water presented toxicological effects for marine organisms, it was verified that dilutions of 100 times were sufficient for not causing toxicological responses. Field monitoring data of the seawater around the Pargo, Pampo and PCR-1 platforms did not demonstrate toxicity in the seawater close to these platforms. The results of environmental monitoring in seawater and sediments proved that alterations were not detected for environmental quality in areas under direct influence of the oil production activities in the Campos and Ceara Basin, as according to results obtained in the dispersion plume modelling for the produced water discharge

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The production of oil and gas is usually accompanied by the production of water, also known as produced water. Studies were conducted in platforms that discharge produced water in the Atlantic Ocean due to oil and gas production by Petrobras from 1996 to 2006 in the following basins: Santos (Brazilian south region), Campos (Brazilian southeast region) and Ceara (Brazilian northeast region). This study encompasses chemical composition, toxicological effects, discharge volumes, and produced water behavior after releasing in the ocean, including dispersion plumes modeling and monitoring data of the marine environment. The concentration medians for a sampling of 50 samples were: ammonia (70 mg L-1), boron (1.3 mg L1), iron (7.4 mg L-1), BTEX (4.6 mg L-1), PAH (0.53 mg L-1), TPH (28 mg L-1); phenols (1.3 mg L-1) and radioisotopes (0.15 Bq L-1 for 226Ra and 0.09 Bq L-1 for 228Ra). The concentrations of the organic and inorganic parameters observed for the Brazilian platforms were similar to the international reference data for the produced water in the North Sea and in other regions of the world. It was found significant differences in concentrations of the following parameters: BTEX (p<0.0001), phenols (p=0.0212), boron (p<0.0001), iron (p<0.0001) and toxicological response in sea urchin Lytechinus variegatus (p<0.0001) when considering two distinguished groups, platforms from southeast and northeast Region (PCR-1). Significant differences were not observed among the other parameters. In platforms with large gas production, the monoaromatic concentrations (BTEX from 15.8 to 21.6 mg L-1) and phenols (from 2 to 83 mg L-1) were higher than in oil plataforms (median concentrations of BTEX were 4.6 mg L-1 for n=53, and of phenols were 1.3 mg L-1 for n=46). It was also conducted a study about the influence of dispersion plumes of produced water in the vicinity of six platforms of oil and gas production (P-26, PPG-1, PCR-1, P-32, SS-06), and in a hypothetical critical scenario using the chemical characteristics of each effluent. Through this study, using CORMIX and CHEMMAP models for dispersion plumes simulation of the produced water discharges, it was possible to obtain the dilution dimension in the ocean after those discharges. The dispersion plumes of the produced water modelling in field vicinity showed dilutions of 700 to 900 times for the first 30-40 meters from the platform PCR-1 discharge point; 100 times for the platform P-32, with 30 meters of distance; 150 times for the platform P-26, with 40 meters of distance; 100 times for the platform PPG-1, with 130 meters of distance; 280 to 350 times for the platform SS-06, with 130 meters of distance, 100 times for the hypothetical critical scenario, with the 130 meters of distance. The dilutions continue in the far field, and with the results of the simulations, it was possible to verify that all the parameters presented concentrations bellow the maximum values established by Brazilian legislation for seawater (CONAMA 357/05 - Class 1), before the 500 meters distance of the discharge point. These results were in agreement with the field measurements. Although, in general results for the Brazilian produced water presented toxicological effects for marine organisms, it was verified that dilutions of 100 times were sufficient for not causing toxicological responses. Field monitoring data of the seawater around the Pargo, Pampo and PCR-1 platforms did not demonstrate toxicity in the seawater close to these platforms. The results of environmental monitoring in seawater and sediments proved that alterations were not detected for environmental quality in areas under direct influence of the oil production activities in the Campos and Ceara Basin, as according to results obtained in the dispersion plume modelling for the produced water discharge

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Context-aware applications are typically dynamic and use services provided by several sources, with different quality levels. Context information qualities are expressed in terms of Quality of Context (QoC) metadata, such as precision, correctness, refreshment, and resolution. On the other hand, service qualities are expressed via Quality of Services (QoS) metadata such as response time, availability and error rate. In order to assure that an application is using services and context information that meet its requirements, it is essential to continuously monitor the metadata. For this purpose, it is needed a QoS and QoC monitoring mechanism that meet the following requirements: (i) to support measurement and monitoring of QoS and QoC metadata; (ii) to support synchronous and asynchronous operation, thus enabling the application to periodically gather the monitored metadata and also to be asynchronously notified whenever a given metadata becomes available; (iii) to use ontologies to represent information in order to avoid ambiguous interpretation. This work presents QoMonitor, a module for QoS and QoC metadata monitoring that meets the abovementioned requirement. The architecture and implementation of QoMonitor are discussed. To support asynchronous communication QoMonitor uses two protocols: JMS and Light-PubSubHubbub. In order to illustrate QoMonitor in the development of ubiquitous application it was integrated to OpenCOPI (Open COntext Platform Integration), a Middleware platform that integrates several context provision middleware. To validate QoMonitor we used two applications as proofof- concept: an oil and gas monitoring application and a healthcare application. This work also presents a validation of QoMonitor in terms of performance both in synchronous and asynchronous requests

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The increasingly request for processing power during last years has pushed integrated circuit industry to look for ways of providing even more processing power with less heat dissipation, power consumption, and chip area. This goal has been achieved increasing the circuit clock, but since there are physical limits of this approach a new solution emerged as the multiprocessor system on chip (MPSoC). This approach demands new tools and basic software infrastructure to take advantage of the inherent parallelism of these architectures. The oil exploration industry has one of its firsts activities the project decision on exploring oil fields, those decisions are aided by reservoir simulations demanding high processing power, the MPSoC may offer greater performance if its parallelism can be well used. This work presents a proposal of a micro-kernel operating system and auxiliary libraries aimed to the STORM MPSoC platform analyzing its influence on the problem of reservoir simulation

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Nowadays due to the security vulnerability of distributed systems, it is needed mechanisms to guarantee the security requirements of distributed objects communications. Middleware Platforms component integration platforms provide security functions that typically offer services for auditing, for guarantee messages protection, authentication, and access control. In order to support these functions, middleware platforms use digital certificates that are provided and managed by external entities. However, most middleware platforms do not define requirements to get, to maintain, to validate and to delegate digital certificates. In addition, most digital certification systems use X.509 certificates that are complex and have a lot of attributes. In order to address these problems, this work proposes a digital certification generic service for middleware platforms. This service provides flexibility via the joint use of public key certificates, to implement the authentication function, and attributes certificates to the authorization function. It also supports delegation. Certificate based access control is transparent for objects. The proposed service defines the digital certificate format, the store and retrieval system, certificate validation and support for delegation. In order to validate the proposed architecture, this work presents the implementation of the digital certification service for the CORBA middleware platform and a case study that illustrates the service functionalities

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In the operational context of industrial processes, alarm, by definition, is a warning to the operator that an action with limited time to run is required, while the event is a change of state information, which does not require action by the operator, therefore should not be advertised, and only stored for analysis of maintenance, incidents and used for signaling / monitoring (EEMUA, 2007). However, alarms and events are often confused and improperly configured similarly by developers of automation systems. This practice results in a high amount of pseudo-alarms during the operation of industrial processes. The high number of alarms is a major obstacle to improving operational efficiency, making it difficult to identify problems and increasing the time to respond to abnormalities. The main consequences of this scenario are the increased risk to personal safety, facilities, environment deterioration and loss of production. The aim of this paper is to present a philosophy for setting up a system of supervision and control, developed with the aim of reducing the amount of pseudo-alarms and increase reliability of the information that the system provides. A real case study was conducted in the automation system of the offshore production of hydrocarbons from Petrobras in Rio Grande do Norte, in order to validate the application of this new methodology. The work followed the premises of the tool presented in ISA SP18.2. 2009, called "life cycle alarm . After the implementation of methodology there was a significant reduction in the number of alarms

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Analisa as práticas de mediação desenvolvidas nas bibliotecas universitárias pelos bibliotecários diante das tecnologias digitais. Para tanto estabelece como objetivo geral analisar de forma comparativa, o impacto e mediação das tecnologias digitais no funcionamento de bibliotecas Universitárias de Portugal e da região Nordeste do Brasil. Integraram esta pesquisa 10 universidades federais brasileiras e 12 universidades públicas portuguesas, com um total geral de 115 bibliotecários, que são os sujeitos participantes. É uma pesquisa qualitativa que adota o método quadripolar – recomendado para os trabalhos desenvolvidos no âmbito das Ciências Sociais Aplicadas, e em especial na área de Ciência da Informação. Através da interação entre os polos: epistemológico, teórico, técnico e morfológico, que fundamentam este método, houve o fortalecimento e a fluidez das questões estudadas. Os resultados dos questionários aplicados aos bibliotecários, bem como da análise dos sítios das bibliotecas pesquisadas, foram interpretados através de um alicerce teórico baseado em três pontos principais: as questões paradigmáticas que envolvem a área de Ciência da Informação, a análise da mediação pós-custodial informacional e científica e as Tecnologias de Informação e Comunicação presentes nas bibliotecas. Como principais resultados vemos que o impacto das tecnologias digitais nas bibliotecas universitárias é considerado pelos bibliotecários brasileiros e portugueses como positivo, com ênfase em dois pontos: a inovação dos suportes de informação e a autossuficiência dos utilizadores. A maior diferença se percebe em relação ao aspecto social, através de uma maior preocupação entre os bibliotecários brasileiros com as barreiras informacionais causadas por questões econômica, social e educacional e sentido com menos intensidade pelos bibliotecários portugueses, que ascendem as tecnologias digitais com mais facilidade. De forma conclusiva, a análise do impacto e a mediação das tecnologias digitais nas bibliotecas pesquisadas, apontam para uma evolução nas práticas mediadoras das bibliotecas universitárias de Portugal e do Nordeste do Brasil e uma convergência laboral entre os bibliotecários portugueses e brasileiros.

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The present study aims to investigate the constructs of Technological Readiness Index (TRI) and the Expectancy Disconfirmation Theory (EDT) as determinants of satisfaction and continuance intention use in e-learning services. Is proposed a theoretical model that seeks to measure the phenomenon suited to the needs of public organizations that offer distance learning course with the use of virtual platforms for employees. The research was conducted from a quantitative analytical approach, via online survey in a sample of 343 employees of 2 public organizations in RN who have had e-learning experience. The strategy of data analysis used multivariate analysis techniques, including structural equation modeling (SEM), operationalized by AMOS© software. The results showed that quality, quality disconfirmation, value and value disconfirmation positively impact on satisfaction, as well as disconfirmation usability, innovativeness and optimism. Likewise, satisfaction proved to be decisive for the purpose of continuance intention use. In addition, technological readiness and performance are strongly related. Based on the structural model found by the study, public organizations can implement e-learning services for employees focusing on improving learning and improving skills practiced in the organizational environment

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The production of water has become one of the most important wastes in the petroleum industry, specifically in the up stream segment. The treatment of this kind of effluents is complex and normally requires high costs. In this context, the electrochemical treatment emerges as an alternative methodology for treating the wastewaters. It employs electrochemical reactions to increase the capability and efficiency of the traditional chemical treatments for associated produced water. The use of electrochemical reactors can be effective with small changes in traditional treatments, generally not representing a significant additional surface area for new equipments (due to the high cost of square meter on offshore platforms) and also it can use almost the same equipments, in continuous or batch flow, without others high costs investments. Electrochemical treatment causes low environmental impact, because the process uses electrons as reagent and generates small amount of wastes. In this work, it was studied two types of electrochemical reactors: eletroflocculation and eletroflotation, with the aim of removing of Cu2+, Zn2+, phenol and BTEX mixture of produced water. In eletroflocculation, an electrical potential was applied to an aqueous solution containing NaCl. For this, it was used iron electrodes, which promote the dissolution of metal ions, generating Fe2+ and gases which, in appropriate pH, promote also clotting-flocculation reactions, removing Cu2+ and Zn2+. In eletroflotation, a carbon steel cathode and a DSA type anode (Ti/TiO2-RuO2-SnO2) were used in a NaCl solution. It was applied an electrical current, producing strong oxidant agents as Cl2 and HOCl, increasing the degradation rate of BTEX and phenol. Under different flow rates, the Zn2+ was removed by electrodeposition or by ZnOH formation, due the increasing of pH during the reaction. To better understand the electrochemical process, a statistical protocol factor (22) with central point was conducted to analyze the sensitivity of operating parameters on removing Zn2+ by eletroflotation, confirming that the current density affected the process negatively and the flow rate positively. For economical viability of these two electrochemical treatments, the energy consumption was calculated, taking in account the kWh given by ANEEL. The treatment cost obtained were quite attractive in comparison with the current treatments used in Rio Grande do Norte state. In addition, it could still be reduced for the case of using other alternative energy source such as solar, wind or gas generated directly from the Petrochemical Plant or offshore platforms

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The new oil reservoirs discoveries in onshore and ultra deep water offshore fields and complex trajectories require the optimization of procedures to reduce the stops operation during the well drilling, especially because the platforms and equipment high cost, and risks which are inherent to the operation. Among the most important aspects stands out the drilling fluids project and their behavior against different situations that may occur during the process. By means of sedimentation experiments, a correlation has been validated to determe the sedimentation particles velocity in variable viscosity fluids over time, applying the correction due to effective viscosity that is a shear rate and time function. The viscosity evolution over time was obtained by carrying out rheologic tests using a fixed shear rate, small enough to not interfere in the fluid gelling process. With the sedimentation particles velocity and the fluid viscosity over time equations an iterative procedure was proposed to determine the particles displacement over time. These equations were implemented in a case study to simulate the cuttings sedimentation generated in the oil well drilling during stops operation, especially in the connections and tripping, allowing the drilling fluid project in order to maintain the cuttings in suspension, avoiding risks, such as stuck pipe and in more drastic conditions, the loss of the well

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The criminal responsibility of the media is analyzed when the criteria for production of news and events involving public safety are produced without considering the technical, legal and ethical practice of journalism in the media factors. Freedom of speech, expression of thought, necessary for professional qualifications and constitutional limits, reaching criminal constitutional principles and the possibilities of criminal liability for offenses practiced in the media are present as key factors legal dialogue in this work. The judgment of the Supreme Court on the unconstitutionality of Law nº. 5.250/67 called Media Law caused a gap in the national legal system, forcing the use of the criminal code to address issues that involve crimes produced in media professional performance. The presumption of innocence is ignored by the professional media during a police investigation where the information published does not respect, including constitutional guarantees: the right to privacy, honor and image. The right to information and the duty to inform media are worked in its constitutional aspect, considering that the same information should be produced is guided by the quality and guiding principles of truth. The constitutional concept of media is presented as information with the appropriate language of the news media, produced and disseminated through the vehicles of mass media, whether in print or digital platform. The presented model of the legal right to information is outlined from a constitutional hermeneutics, increasing the production of news as a result of the occupation of journalist in different news platforms, guaranteeing the quality of this prolific law. Under the Freedom of professional activity of the journalist, the constitutional limits are addressed in line with the reality of (non) regulation of their profession, considering the constitutional abuses committed in the exercise of that activity linked to communication fences. Jusphilosophic field reaches the limits of the duty of truth in journalism as a tool for spreading news, respect the audience and compatibility with the constitutional state. Using the conceptual and doctrinal aspects, this criminal offense is parsed from the journalistic practice and the publication of news involving public safety, with the hypothetical field consummation of that crime through the eventual intention. As a form of judgment against these crimes produced in honor media presents the court of the jury as a legitimate form of democratic decision

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Analyzes the development experience in the Territories of Mato Grande and Sertão do Apodi in the state of Rio Grande do Norte, evaluating the actions of the National Program for Strengthening Family Agriculture, specifically the line of infrastructure (PRONAF-INFRA), and the National Program for Sustainable Development of Rural Territories (PRONAT) in these territories. Summarizes the various rural development approaches and takes the theoretical assumptions of territorial development, the concept of constructed territory and market-plan territory, further the cycle model to analyze public policies selected these experiences. Thus, we propose to test the hypothesis that most of the actions implemented would lead to the formation of market-plan territories, in other words, perceived only as a platform for the presentation of projects. The literature and documents, combined with case studies, interviews and direct observation of the meetings of committees, showed that, despite two boards are under the same laws, rules and formal regulations, have clear differences when considering the theory and concepts that were used as reference. The Apodi s territory is closer to a constructed space thus the search for a broader agenda, more autonomous and more appropriate to the reality experienced by local actors. On other hand the Territory of Mato Grande had the characteristics of a market-plan territory more present. As the result, the territory of Sertão do Apodi accesses not only as part of a greater number of policies and funding sources, ensuring a greater and more diverse investment volume than the territory of Mato Grande. Despite these differences, studies have shown that territorial boards surveyed are still far from becoming the main forum for managing the development from conception planning socially constructed. Showed, finally, that territorial development strategy is relevant, but requires a long walk and a deep and continuous learning process to be successfully implemented in rural areas of Northeast Brazil