Parallel Cyclostationarity-Exploiting Algorithm for Energy-Efficient Spectrum Sensing

The evolution of wireless communication systems leads to Dynamic Spectrum Allocation for Cognitive Radio, which requires reliable spectrum sensing techniques. Among the spectrum sensing methods proposed in the literature, those that exploit cyclostationary characteristics of radio signals are particularly suitable for communication environments with low signal-to-noise ratios, or with non-stationary noise. However, such methods have high computational complexity that directly raises the power consumption of devices which often have very stringent low-power requirements. We propose a strategy for cyclostationary spectrum sensing with reduced energy consumption. This strategy is based on the principle that p processors working at slower frequencies consume less power than a single processor for the same execution time. We devise a strict relation between the energy savings and common parallel system metrics. The results of simulations show that our strategy promises very significant savings in actual devices.

Programa alfabetização solidária: um estudo sobre a experiência no município de Lagoa de Pedras/RN (1997 - 2003)

The educational reform of the 90 s was tainted by the objectives of the fiscal adjustments, resulting in the redefinition of the state s role in the financing and offering of teaching services, and bringing about a shuffling of the responsibility between the public and private sectors to promote education to young people and adults. The 90 s also highlighted the proliferation of providers and the multiplication of Educational Programs for Youths and Adults (EJA), implemented through partnerships between governmental and nongovernmental agencies. During this period of time, the agenda of educational responsibilities concerning analphabetism was organized in a process of decentralized of the state, with the following political, social, and economic objectives: to reduce the public deficit, increasing public savings and the financial capacity of the state to concentrate resources in areas considered indispensable to direct intervention; to increase the efficiency of the social services moffered or funded by the state, giving citizens more at a lower cost, and spreading services to more remote areas, expanding access to reach those most in need; to increase the participation of citizens in public management, stimulating communitarian acts as well as developing efforts towards the effective coordination of public figures in the implementation of associated social services. Thus, Assistance Programs co-financed by the government try to deal with the problem of analphabetism. Within the sphere of the 90 s educational policy decentralization, we come to see how the agenda dedicated to the reduction of analphabetism was formed by the Solidarity Alphabetization Program (PAS). Between 1997 and 2003, the latter agenda s decentralizing proposal was integrated in the management partnership for the operationalization of tasks and resources faced with the execution of the formal objectives. In this study, we identify the dimensions of the implantation and progress of the tasks carried out by PAS, in the municipality of Lagoa de Pedras/RN. However, we consider these Programs to assist in the process without guaranteeing the reduction of the causes or substituting the responsibility of the system once the monetary resources for program maintenance provided by the partners is exhausted

Sistema Híbrido de Inferência Baseado em Análise de Componentes Principais e Redes Neurais Artificiais Aplicado a Plantas de Processamento de Gás Natural

Nowadays, where the market competition requires products with better quality and a constant search for cost savings and a better use of raw materials, the research for more efficient control strategies becomes vital. In Natural Gas Processin Units (NGPUs), as in the most chemical processes, the quality control is accomplished through their products composition. However, the chemical composition analysis has a long measurement time, even when performed by instruments such as gas chromatographs. This fact hinders the development of control strategies to provide a better process yield. The natural gas processing is one of the most important activities in the petroleum industry. The main economic product of a NGPU is the liquefied petroleum gas (LPG). The LPG is ideally composed by propane and butane, however, in practice, its composition has some contaminants, such as ethane and pentane. In this work is proposed an inferential system using neural networks to estimate the ethane and pentane mole fractions in LPG and the propane mole fraction in residual gas. The goal is to provide the values of these estimated variables in every minute using a single multilayer neural network, making it possibly to apply inferential control techniques in order to monitor the LPG quality and to reduce the propane loss in the process. To develop this work a NGPU was simulated in HYSYS R software, composed by two distillation collumns: deethanizer and debutanizer. The inference is performed through the process variables of the PID controllers present in the instrumentation of these columns. To reduce the complexity of the inferential neural network is used the statistical technique of principal component analysis to decrease the number of network inputs, thus forming a hybrid inferential system. It is also proposed in this work a simple strategy to correct the inferential system in real-time, based on measurements of the chromatographs which may exist in process under study

Foucault e a arte do cuidado de si: uma nova possibilidade de Discussão para a formação continuada de professores de língua inglesa

This thesis proposes a new thinking on the English teacher and their continuing education, leaving the picture emerging of a new professional, who is producing and being produced. From this perspective, I present an analysis of self writing of thirteen student-teachers, teachers on how they position themselves to be discursively constituted as subjects in the context of continuing education. As part of Applied Linguistics, the theory and method that supports the analysis of data are articulate key elements of Foucault notions, namely:The care of the self, seeking their connection with one another and care of and the self writing. In the theoretical notions of these elements are implied notions of others, such as speech, ethics, technology of the self, subject and truth. (Foucault, 1984, 1995, 2004c, 2006), and questioning the ethics of the subject. I propose to examine selected excerpts from the self writings of student teachers with a specialization in Teaching and Learning the English Language, seeking linguistic processes in the material production of subjectivities.In order to analyze the process of subjectivation, I examine the discursive statements of selected cuts, aiming to learn more specifically, the points of identification and fragments of the uniqueness of the teachers, showing how they care for themselves and reflect upon them in building their subjectivity from the technologies of the self, to occupy the position of English Language teachers. The results show that, in the exercise of self writing, the subject falls, and a practice of asceticism, discursively construct her/his subjectivity

Otimização no uso de martelos e bigornas para quebrar sementes por macacos prego (Cebus flavius e C. libidinosus) no Bioma Caatinga

Recently, capuchin monkeys (Cebus spp.) inhabitants of dry environments and with restriction of fleshy fruits, have been the subject of several studies regarding the use of instruments. During behaviour of using stones to crack open nuts there is evidence of selection of more effective hammers, as well as selection of anvils related to reducing the risk of predation. The aim of this study was to determine whether two groups of capuchin monkeys (C.flavius and and C.libidinosus) inhabitants of the Caatinga of Rio Grande do Norte make choice of hammers and anvils. The record of weight and location of stones indicated active choices of with what (choice of hammers) and where (selection of anvils) to crack open encapsulated seeds. The choice of hammers to break nuts depended on the type and degree of ripeness seed. Thus, smaller seeds were smashed with lighter hammers and larger seeds with heavier hammers. Still, C. flavius was the only species that presented a refinement in the choice of hammers that depended on the ripeness of seeds. For both species of capuchin monkeys studied, the nut-crack sites were not spread in accordance with the spatial distribution of seed-producing species, suggesting that the capuchin monkeys promote active choice of anvils. Thus, in environments with more escape routes through the trees, the nut-crack sites were found further apart than in regions that had less chance of escape through the trees. Also, there was a difference in the spacing of the anvils to depend on the type of seed: sites used to crack larger and more caloric seeds were found farther apart than the sites used to crack smaller and less caloric seeds, suggesting a pattern of avoiding direct competition. We conclude that the capuchin monkeys maximize energy savings and reduced risk of predation and the costs of food competition during the behaviour of using stones to crack open nuts

"Ombro a ombro com os mais fracos": a inserção de João Café Filho nos espaços do trabalhador na cidade do Natal 1922 - 1937

The purpose of this thesis is to analyze how João Café Filho constituted a discourse of advocate of the labor movement and workers in different sociability spaces. It is intended to understand, on one hand, how political relations were established between different categories of workers and the ‘middle classes’ and, on the other hand, how places were instituted to house the meeting of these relations. It a ims to understand the insertion of Café Filho in union activities in the urban world. It demonstrates specificities of the political culture in Natal emphasizing the dispute between a city politically ruled by a still reigning rural paternalistic mentality and the rise of a new way to experience the urban conflicts which appeared. Temporally, the work is delimited between 1922 (proclaimed by Café Filho himself as the initial period of his political action) and 1937 (when he broke up with Vargas and went into exile in Argentina). The research was constituted by three main document types: several published newspapers between the decades of 1920 and 1930 in the cities of Natal, Recife, São Paulo, Porto Alegre and Rio de Janeiro; the autobiographical memoirs written by Café Filho himself and memoirs of other people who lived in his time. The main pillars that have supported the work were: the concepts of society and individuals (ELIAS, 1994; 1995), political cultures (BERSTEIN, 1998) and theater of the memory (GOMES, 2004); the sociability spaces category (CERTEAU, 1994; MALATIAN, 2001; RIOX, 1996); the biography notion (DOSSE, 2009; LORIGA, 2011). We demonstrated that Café Filho acted in some sociability spaces as: the Jornal do Norte, the Federação Regional do Trabalho and the Partido Democrático Nacional. In such spaces, Café Filho, gradually, become an important leader of workers and, at the same time, linked to national entities led to the opposition that fight against the power established in the Brazilian First Republic. In Café Filho’s interpretation, workers were individuals who needed to fight against the political structures prevailing at that time because the poor living conditions and the low representativeness of this group were caused by the way the political system in the First Republic was structured. After the 1930 Movement, the 3 de Outubro Club, the Jornal and the Labor Federation of Natal were constituted in spaces where the cafeista critical discourse about the government was changed: workers should follow the official syndicalism and defend the 1930 Movement which put Vargas in the presidency of the Republic.

Parallel Cyclostationarity-Exploiting Algorithm for Energy-Efficient Spectrum Sensing

The evolution of wireless communication systems leads to Dynamic Spectrum Allocation for Cognitive Radio, which requires reliable spectrum sensing techniques. Among the spectrum sensing methods proposed in the literature, those that exploit cyclostationary characteristics of radio signals are particularly suitable for communication environments with low signal-to-noise ratios, or with non-stationary noise. However, such methods have high computational complexity that directly raises the power consumption of devices which often have very stringent low-power requirements. We propose a strategy for cyclostationary spectrum sensing with reduced energy consumption. This strategy is based on the principle that p processors working at slower frequencies consume less power than a single processor for the same execution time. We devise a strict relation between the energy savings and common parallel system metrics. The results of simulations show that our strategy promises very significant savings in actual devices.