Estratégias distribuídas para a coexistência de redes de banda larga sem fio em bandas não-licensiadas

The increasing demand for Internet data traffic in wireless broadband access networks requires both the development of efficient, novel wireless broadband access technologies and the allocation of new spectrum bands for that purpose. The introduction of a great number of small cells in cellular networks allied to the complimentary adoption of Wireless Local Area Network (WLAN) technologies in unlicensed spectrum is one of the most promising concepts to attend this demand. One alternative is the aggregation of Industrial, Science and Medical (ISM) unlicensed spectrum to licensed bands, using wireless networks defined by Institute of Electrical and Electronics Engineers (IEEE) and Third Generation Partnership Project (3GPP). While IEEE 802.11 (Wi-Fi) networks are aggregated to Long Term Evolution (LTE) small cells via LTE / WLAN Aggregation (LWA), in proposals like Unlicensed LTE (LTE-U) and LWA the LTE air interface itself is used for transmission on the unlicensed band. Wi-Fi technology is widespread and operates in the same 5 GHz ISM spectrum bands as the LTE proposals, which may bring performance decrease due to the coexistence of both technologies in the same spectrum bands. Besides, there is the need to improve Wi-Fi operation to support scenarios with a large number of neighbor Overlapping Basic Subscriber Set (OBSS) networks, with a large number of Wi-Fi nodes (i.e. dense deployments). It is long known that the overall Wi-Fi performance falls sharply with the increase of Wi-Fi nodes sharing the channel, therefore there is the need for introducing mechanisms to increase its spectral efficiency. This work is dedicated to the study of coexistence between different wireless broadband access systems operating in the same unlicensed spectrum bands, and how to solve the coexistence problems via distributed coordination mechanisms. The problem of coexistence between different networks (i.e. LTE and Wi-Fi) and the problem of coexistence between different networks of the same technology (i.e. multiple Wi-Fi OBSSs) is analyzed both qualitatively and quantitatively via system-level simulations, and the main issues to be faced are identified from these results. From that, distributed coordination mechanisms are proposed and evaluated via system-level simulations, both for the inter-technology coexistence problem and intra-technology coexistence problem. Results indicate that the proposed solutions provide significant gains when compare to the situation without distributed coordination.

Implementação de um Módulo de Supervisão para um Sistema de Detecção de Vazamentos em Dutos de Petróleo

The transport of fluids through pipes is used in the oil industry, being the pipelines an important link in the logistics flow of fluids. However, the pipelines suffer deterioration in their walls caused by several factors which may cause loss of fluids to the environment, justifying the investment in techniques and methods of leak detection to minimize fluid loss and environmental damage. This work presents the development of a supervisory module in order to inform to the operator the leakage in the pipeline monitored in the shortest time possible, in order that the operator log procedure that entails the end of the leak. This module is a component of a system designed to detect leaks in oil pipelines using sonic technology, wavelets and neural networks. The plant used in the development and testing of the module presented here was the system of tanks of LAMP, and its LAN, as monitoring network. The proposal consists of, basically, two stages. Initially, assess the performance of the communication infrastructure of the supervisory module. Later, simulate leaks so that the DSP sends information to the supervisory performs the calculation of the location of leaks and indicate to which sensor the leak is closer, and using the system of tanks of LAMP, capture the pressure in the pipeline monitored by piezoresistive sensors, this information being processed by the DSP and sent to the supervisory to be presented to the user in real time

A Acessibilidade como veículo de inclusão social: proposta de dispositivo computacional para os deficientes visuais da cidade de Natal/RN

This study aims to propose a computing device mechanism which is capable to permit a tactile communication between individuals with visual impairment (blindness or low vision) through the Internet or through a local area network (LAN - Local Network Address). The work was developed under the research projects that currently are realized in the LAI (Laboratory of Integrated Accessibility) of the Federal University of Rio Grande do Norte. This way, the research was done in order to involve a prototype capable to recognize geometries by students considered blind from the Institute of Education and Rehabilitation of Blind of Rio Grande do Norte (IERC-RN), located in Alecrim neighborhood, Natal/RN. Besides this research, another prototype was developed to test the communication via a local network and Internet. To analyze the data, a qualitative and quantitative approach was used through simple statistical techniques, such as percentages and averages, to support subjective interpretations. The results offer an analysis of the extent to which the implementation can contribute to the socialization and learning of the visually impaired. Finally, some recommendations are suggested for the development of future researches in order to facilitate the proposed mechanism.

Monitoramento por dgps e análise dos processos erosivos da linha de costa na praia de Pirangi do Norte - Parnamirim / RN

Through out the course of a steady increase in search and recovery of space in the coastal zone, there is also an expanding concern about the erosion processes of this area. The main problem in coastal areas is that urbanization occurs in a disorderly fashion and unsustainable, further aggravating the problems of coastal dynamics. The study area of this work is located on the southern coast of Pirangi do Norte beach to about 20km south of Natal, capital of Rio Grande do Norte in the Parnamirim City. This area has the length of approximately 1km, divided into three sections (Western, Central and Eastern) with a morphology consisting of a tableland at the top, sea cliffs in the West and Central parts and sand dunes in the Eastern section, both vegetated, and a coastal plain on the inferior part associated with the presence of beach rocks. This study aimed to analyze the erosion processes operating in the excerpt of Pirangi do Norte beach and assess the feasibility of their monitoring making use of DGPS (Global Positioning System Differential mode). During the work it was carried out a physical description of the area through photo-interpretation and site survey after measurement of the shoreline in the period between November 2004 and November 2009 and beach profiles between August 2005 and July 2006. The analysis of the results of the annual surveys showed the occurrence of variations of the shoreline along the stretch traveled. Sites are identified in advancement coast from the sea and it was verified in loco the presence of erosion with deposition of materials on the lower part of the coastal bluff, the former position of the shoreline, showing a false notion of advancing it. This leads to the conclusion that the data collected in a survey of the shoreline should always be accompanied by photographic records of the local area and with the highest rate of erosion, thus avoiding the mistake of treating the deposit materials as evidence of progress coast. At the end of the study, after a review of various works to mitigate the erosion in the coastal zone, it is recommended to the area of study the adoption of an artificial feeding of the beach, aiming the minimization of the erosive effects of the tides. Moreover, it is suggested that even the continuity of monitoring, maintenance of existing vegetation and control of the occupation on the edge of sea cliffs

Implementação de um Módulo de Supervisão para um Sistema de Detecção de Vazamentos em Dutos de Petróleo

The transport of fluids through pipes is used in the oil industry, being the pipelines an important link in the logistics flow of fluids. However, the pipelines suffer deterioration in their walls caused by several factors which may cause loss of fluids to the environment, justifying the investment in techniques and methods of leak detection to minimize fluid loss and environmental damage. This work presents the development of a supervisory module in order to inform to the operator the leakage in the pipeline monitored in the shortest time possible, in order that the operator log procedure that entails the end of the leak. This module is a component of a system designed to detect leaks in oil pipelines using sonic technology, wavelets and neural networks. The plant used in the development and testing of the module presented here was the system of tanks of LAMP, and its LAN, as monitoring network. The proposal consists of, basically, two stages. Initially, assess the performance of the communication infrastructure of the supervisory module. Later, simulate leaks so that the DSP sends information to the supervisory performs the calculation of the location of leaks and indicate to which sensor the leak is closer, and using the system of tanks of LAMP, capture the pressure in the pipeline monitored by piezoresistive sensors, this information being processed by the DSP and sent to the supervisory to be presented to the user in real time

Avaliação ecológico-econômica do manguezal de Macau/RN e a importância da aplicação de práticas preservacionistas pela indústria petrolífera local

This work presents the results of a survey in oil-producing region of the Macau City, northern coast of Rio Grande do Norte. All work was performed under the Project for Monitoring Environmental Change and the Influence of Hydrodynamic forcing on Morphology Beach Grass Fields, Serra Potiguar in Macau, with the support of the Laboratory of Geoprocessing, linked to PRH22 - Training Program in Geology Geophysics and Information Technology Oil and Gas - Department of Geology/CCET/UFRN and the Post-Graduation in Science and Engineering Oil/PPGCEP/UFRN. Within the economic-ecological context, this paper assesses the importance of mangrove ecosystem in the region of Macau and its surroundings as well as in the following investigative exploration of potential areas for projects involving reforestation and / or Environmental Restoration. At first it was confirmed the ecological potential of mangrove forests, with primary functions: (i) protection and stabilization of the shoreline, (ii) nursery of marine life, and (iii) source of organic matter to aquatic ecosystems, (iv) refuge of species, among others. In the second phase, using Landsat imagery and techniques of Digital Image Processing (DIP), I came across about 18,000 acres of land that can be worked on environmental projects, being inserted in the rules signed the Kyoto Protocol to the market carbon. The results also revealed a total area of 14,723.75 hectares of activity of shrimp production and salting that can be harnessed for the social, economic and environmental potential of the region, considering that over 60% of this area, ie, 8,800 acres, may be used in the planting of the genus Avicennia considered by the literature that the species best sequesters atmospheric carbon, reaching a mean value of 59.79 tons / ha of mangrove

Controle fuzzy espacialmente diferenciado para um sistema de irrigação

Traditional irrigation projects do not locally determine the water availability in the soil. Then, irregular irrigation cycles may occur: some with insufficient amount that leads to water deficit, other with excessive watering that causes lack of oxygen in plants. Due to the nonlinear nature of this problem and the multivariable context of irrigation processes, fuzzy logic is suggested to replace commercial ON-OFF irrigation system with predefined timing. Other limitation of commercial solutions is that irrigation processes either consider the different watering needs throughout plant growth cycles or the climate changes. In order to fulfill location based agricultural needs, it is indicated to monitor environmental data using wireless sensors connected to an intelligent control system. This is more evident in applications as precision agriculture. This work presents the theoretical and experimental development of a fuzzy system to implement a spatially differentiated control of an irrigation system, based on soil moisture measurement with wireless sensor nodes. The control system architecture is modular: a fuzzy supervisor determines the soil moisture set point of each sensor node area (according to the soil-plant set) and another fuzzy system, embedded in the sensor node, does the local control and actuates in the irrigation system. The fuzzy control system was simulated with SIMULINK® programming tool and was experimentally built embedded in mobile device SunSPOTTM operating in ZigBee. Controller models were designed and evaluated in different combinations of input variables and inference rules base

O Desenvolvimento local sustentável no semi-árido nordestino: um estudo de caso na comunidade de mirandas, Caraúbas/RN

Brazil s semi-arid region is an immense territory characterized by a mosaic of natural environments and human settlements. Inside this multifaceted framework, there are problems that are specific to the region (the water resources situation, for example) while others are more universal (such as the inequality between men and women). The circumstances that give rise to these problems are complex and require a holistic view so that our understanding can go beyond the simple concept that this is a problem region . The semi-arid must be perceived as a viable area in need of a new analysis, taking into account its successes, limitations, challenges and the strategic public policy framework that guarantees its sustainable development. The dissertation analyzes, from a sustainable local development perspective, the experience of the Northeastern Brazil Groundwater Project (PROASNE), carried out from 2001 to 2003, in partnership with the Waters and Sewers Company of Rio Grande do Norte (CAERN) in the rural community of Mirandas, municipality of Caraúbas/RN, situated in the middle of the northeastern Brazil semi-arid region

O turismo de base local como um possível indutor de desenvolvimento rural: uma análise da realidade e das potencialidades no distrito de dondo-moçambique

The current debate on rural development focuses on the territorial approach, recognizing the multifunctional character of rural areas. Emphasize the use of endogenous forces, the need of implement policies which valorize local specificities, the participation of social actors in revitalization of rural areas. In this context tourism enters as a means to induce a new dynamic to rural areas, since the activity is regarded as a channel for the upgrading of the natural and cultural resources and the rural way of life. This study focuses on local-based tourism as a promoter of rural development, giving an analysis of the social reality and potential for this tourism in the district of Dondo. In it, is proposed to analyze the potential for development of local-based tourism in the district of Dondo, assessing the extent to which local reality enables the inclusion of the community in the management of local tourism resources. For this, was showed the inclusion of local-based tourism in the current context of rural development, was identified and organized systematically the factors that influence the implementation of local-based tourism in the study area and was verified as far as possible the study area corresponds to the constraints identified, showing how local-based tourism can best been encouraged. Was adopted a qualitative methodological approach to both the procedures and data processing, but also by critical approach, using bibliographical research, semi-structured interviews that fell on the group of public administrators who work in tourism and community leaders. The critical analysis was based on the principles of sustainability o Sachs particular ecological, social, cultural, economic, space, beyond the analysis of political and institutional aspects. The survey results show that the district of Dondo has a potential for implementing a model of tourism development on a local basis, since it is rich in natural and cultural research, benefits from good network accessibility in the context of the market in the region, the population live according to their habits and customs and value their identity. There is also a good cooperation between community members, although not in tourism, a fact which is observed through the lever of community participation in associations, cooperatives, working in areas such as agriculture, fishing, environment, civic education etc. It also has public funding sources to augment or stimulate local investment. Despite obstacles such as inexistence of policies and local plans for tourism development, lack of awareness of tourism, lack of basic infrastructure, as well as equipment and facilities to support tourism, the results shows that these problems can be solved through a public commitment from both government, and community through a joint planning and participation

Políticas de turismo e comunidade local no litoral potiguar

This research focuses on raise the discussion of existance tourism policies in Rio Grande do Norte and its contributions to the integration of local communities in the coastal tourist activity. Guided by the background of the neoliberalism and its influence on the model of tourism development adopted in Rio Grande do Norte. For that, were surveyed the concrete realities of coastal localities of the municipalities of Ceará-Mirim, Extremoz, Parnamirim and Nísia Floresta covered by Prodetur-RN I and II, by being part of the tourist portion of the state that have received domestic and international investment and, because are located in the geographical area of the Potiguar capital, Natal. We interviewed the municipal managers and the residents of local communities who live in municipalities more than ten years. Also, was raised a discussion on the role of the state as the main agent of public policies and hegemonic facilitator in the attraction of domestic and foreign investments, with the main scenario the neoliberal model of economic development. Here discuss ways and strategies of socio-political organization of local communities, with regard to the inclusion in the tourist and, pointing to the critical development model in question and signaling other concepts of development model, such as local basis, for example. By the ending of the research, was concluded that the model of development of the tourism in the Rio Grande do Norte is reflected of the way of life of the society, that the communities live in precarious conditions and that the way of inclusion in the tourism is almost incipient. Also, it was possible to detect the inexistence of public politics of tourism that promoted the planning of the tourist activity, as well as, the inclusion of the communities in the decision processes and that, searched the development on the basis of the principles of sustainable and local autonomy

Analise dos impactos socioambientais da instalacao das unidades de bombeio de petroleo na area urbana de Mossoro - RN

Conselho Nacional de Desenvolvimento Científico e Tecnológico