BBA: A binary bat algorithm for feature selection

Feature selection aims to find the most important information from a given set of features. As this task can be seen as an optimization problem, the combinatorial growth of the possible solutions may be in-viable for a exhaustive search. In this paper we propose a new nature-inspired feature selection technique based on the bats behaviour, which has never been applied to this context so far. The wrapper approach combines the power of exploration of the bats together with the speed of the Optimum-Path Forest classifier to find the set of features that maximizes the accuracy in a validating set. Experiments conducted in five public datasets have demonstrated that the proposed approach can outperform some well-known swarm-based techniques. © 2012 IEEE.

Structural and Phylogenetic Studies with MjTX-I Reveal a Multi-Oligomeric Toxin - a Novel Feature in Lys49-PLA2s Protein Class

The mortality caused by snakebites is more damaging than many tropical diseases, such as dengue haemorrhagic fever, cholera, leishmaniasis, schistosomiasis and Chagas disease. For this reason, snakebite envenoming adversely affects health services of tropical and subtropical countries and is recognized as a neglected disease by the World Health Organization. One of the main components of snake venoms is the Lys49-phospholipases A2, which is catalytically inactive but possesses other toxic and pharmacological activities. Preliminary studies with MjTX-I from Bothrops moojeni snake venom revealed intriguing new structural and functional characteristics compared to other bothropic Lys49-PLA2s. We present in this article a comprehensive study with MjTX-I using several techniques, including crystallography, small angle X-ray scattering, analytical size-exclusion chromatography, dynamic light scattering, myographic studies, bioinformatics and molecular phylogenetic analyses.Based in all these experiments we demonstrated that MjTX-I is probably a unique Lys49-PLA2, which may adopt different oligomeric forms depending on the physical-chemical environment. Furthermore, we showed that its myotoxic activity is dramatically low compared to other Lys49-PLA2s, probably due to the novel oligomeric conformations and important mutations in the C-terminal region of the protein. The phylogenetic analysis also showed that this toxin is clearly distinct from other bothropic Lys49-PLA2s, in conformity with the peculiar oligomeric characteristics of MjTX-I and possible emergence of new functionalities inresponse to environmental changes and adaptation to new preys. © 2013 Salvador et al.

Exterior orientation of CBERS-2B imagery using multi-feature control and orbital data

The major contribution of this paper relates to the practical advantages of combining Ground Control Points (GCPs), Ground Control Lines (GCLs) and orbital data to estimate the exterior orientation parameters of images collected by CBERS-2B (China-Brazil Earth Resources Satellite) HRC (High-resolution Camera) and CCD (High-resolution CCD Camera) sensors. Although the CBERS-2B is no longer operational, its images are still being used in Brazil, and the next generations of the CBERS satellite will have sensors with similar technical features, which motivates the study presented in this paper. The mathematical models that relate the object and image spaces are based on collinearity (for points) and coplanarity (for lines) conditions. These models were created in an in-house developed software package called TMS (Triangulation with Multiple Sensors) with multi-feature control (GCPs and GCLs). Experiments on a block of four CBERS-2B HRC images and on one CBERS-2B CCD image were performed using both models. It was observed that the combination of GCPs and GCLs provided better bundle block adjustment results than conventional bundle adjustment using only GCPs. The results also demonstrate the advantages of using primarily orbital data when the number of control entities is reduced. © 2013 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).

Binary Bat Algorithm for Feature Selection

Feature selection aims to find the most important information to save computational efforts and data storage. We formulated this task as a combinatorial optimization problem since the exponential growth of possible solutions makes an exhaustive search infeasible. In this work, we propose a new nature-inspired feature selection technique based on bats behavior, namely, binary bat algorithm The wrapper approach combines the power of exploration of the bats together with the speed of the optimum-path forest classifier to find a better data representation. Experiments in public datasets have shown that the proposed technique can indeed improve the effectiveness of the optimum-path forest and outperform some well-known swarm-based techniques. © 2013 Copyright © 2013 Elsevier Inc. All rights reserved.

BCS: A Binary Cuckoo Search algorithm for feature selection

Feature selection has been actively pursued in the last years, since to find the most discriminative set of features can enhance the recognition rates and also to make feature extraction faster. In this paper, the propose a new feature selection called Binary Cuckoo Search, which is based on the behavior of cuckoo birds. The experiments were carried out in the context of theft detection in power distribution systems in two datasets obtained from a Brazilian electrical power company, and have demonstrated the robustness of the proposed technique against with several others nature-inspired optimization techniques. © 2013 IEEE.

Optimizing feature selection through binary charged system search

Feature selection aims to find the most important information from a given set of features. As this task can be seen as an optimization problem, the combinatorial growth of the possible solutions may be inviable for a exhaustive search. In this paper we propose a new nature-inspired feature selection technique based on the Charged System Search (CSS), which has never been applied to this context so far. The wrapper approach combines the power of exploration of CSS together with the speed of the Optimum-Path Forest classifier to find the set of features that maximizes the accuracy in a validating set. Experiments conducted in four public datasets have demonstrated the validity of the proposed approach can outperform some well-known swarm-based techniques. © 2013 Springer-Verlag.

A wrapper approach for feature selection based on Bat Algorithm and Optimum-Path Forest

Besides optimizing classifier predictive performance and addressing the curse of the dimensionality problem, feature selection techniques support a classification model as simple as possible. In this paper, we present a wrapper feature selection approach based on Bat Algorithm (BA) and Optimum-Path Forest (OPF), in which we model the problem of feature selection as an binary-based optimization technique, guided by BA using the OPF accuracy over a validating set as the fitness function to be maximized. Moreover, we present a methodology to better estimate the quality of the reduced feature set. Experiments conducted over six public datasets demonstrated that the proposed approach provides statistically significant more compact sets and, in some cases, it can indeed improve the classification effectiveness. © 2013 Elsevier Ltd. All rights reserved.

A documentação nas práticas artísticas dos grupos Arte/Ação e 3Nós3

Pós-graduação em Artes - IA

Põe tapioca, põe farinha d’água?: gastronomia do açaí e identidade socioespacial e cultural na Grande Belém

O presente trabalho teve como objetivo principal analisar as mudanças nas formas de venda e consumo do açaí na Região Metropolitana de Belém (RMB), e sua relação com a identidade de lugar de seus consumidores. O interesse pelo tema teve origem na observação da ocorrência da globalização do açaí, alimento base da dieta das populações amazônicas de origem ribeirinha que hoje é largamente consumido fora da Região Amazônica, em padrões muito diferentes daqueles nela estabelecidos. A escolha da RMB como lócus de pesquisa se justifica pelo fato de que nela se concentra alto consumo de açaí, nos padrões tradicionais e nos modernos, suscitando questionamentos sobre os efeitos dessa convivência na vida cotidiana dos que a habitam. Teoricamente, a pesquisa articula a definição de identidade de lugar de Abe-Lima (2012) com as elaborações de Henri Lefèbvre (1991) sobre a vida cotidiana no mundo moderno e com teoria dos circuitos econômicos de Milton Santos (2008). Metodologicamente, foi adotada uma estratégia multimétodos, envolvendo pesquisa documental, um painel de especialistas com 5 entidades de acompanhamento da produção de açaí, observações pautadas na etnografia urbana em 9 locais de venda e entrevistas semiabertas com 40 consumidores de açaí, maiores de 18 anos e residentes na RMB, recrutados por meio de cadeia tipo bola de neve. Além dos roteiros de entrevistas, foram utilizados como estratégias de coleta de dados diários de campo e fotografias. O conjunto dos dados foi submetido à técnica da análise de conteúdo temática, com eventual apoio do software QDA Miner Lite. Os resultados situaram a globalização do açaí em meados da década de 1990, momento de intensificação dos efeitos da metropolização em Belém, como o aumento populacional, a segregação espacial e a imposição de um ritmo de vida mais acelerado. As análises apontaram que tal processo significou a entrada do açaí no circuito superior da economia, com um processo produtivo mais organizado, utilizando mais tecnologia e envolvendo maiores volumes financeiros, atingindo escala industrial. No entanto, prevalece na RMB o processamento artesanal, em estruturas de pequeno porte, construídas em alvenaria, de organização simples e controle financeiro ausente. O consumo público aumentou, com grande número de locais especializados na oferta de açaí, em caráter de entretenimento, sendo incipiente a adesão a novos acompanhamentos, como granola e aveia. A preferência pelos acompanhamentos tradicionais, como farinha d’água ou de tapioca, açúcar e peixe, permanece, assim como pelo consumo privado, no âmbito da casa, que tem sido favorecido pela disponibilidade do serviço de entrega, recurso recente. A frequência geral de consumo diminuiu, em função do aumento de preço e de mudanças na rotina, como aumento da distância entre local de trabalho e residência. A pesquisa permitiu reafirmar a importância do açaí na vida cotidiana dos belenenses que o consomem, para os quais ele funciona como elemento de distintividade, continuidade, autoestima e autoeficácia, em estreita relação com aspectos próprios da metrópole. Por esse motivo, torna-se preocupante que o acesso a açaí de qualidade, nos padrões desejados pelos indivíduos, esteja tornando-SE privilégio inacessível aos consumidores de menor poder aquisitivo. Assim, espera-se que o conjunto de dados contribua para a compreensão da importância de políticas públicas voltadas ao açaí que considerem melhor as demandas daqueles que o consomem.

Audiodescrição: um recurso de acessibilidade na televisão digital

Pós-graduação em Televisão Digital: Informação e Conhecimento - FAAC

Feature extraction in pressure signals for leak detection in water networks

Techniques based on signal analysis for leak detection in water supply systems typically use long pressure and/or flow data series of variable length. This paper presents the feature extraction from pressure signals and their application to the identification of changes related to the onset of a leak. Example signals were acquired from an experimental laboratory circuit, and features were extracted from temporal domain and from transformed signals. Statistical analysis of features values and a classification method were applied. It was verified the feasibility of using feature vectors for distinguish data acquired in the absence or presence of a leak.

O amanhã de quem cresce: influências e valores presentes na constituição de projetos de vida de jovens adolescentes de um curso técnico de uma instituição estadual

Pós-graduação em Educação - FFC

Supervised variational relevance learning, an analytic geometric feature selection with applications to omic datasets

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A importância da gestão de pessoas no terceiro setor: estudo sobre as instituições na cidade de Passos - MG

Pós-graduação em Serviço Social - FCHS

Ontologias no processo de indexação automática de documentos textuais

Pós-graduação em Ciência da Informação - FFC