Lattice constellations and codes from quadratic number fields

We propose new classes of linear codes over integer rings of quadratic extensions of Q, the field of rational numbers. The codes are considered with respect to a Mannheim metric, which is a Manhattan metric modulo a two-dimensional (2-D) grid. In particular, codes over Gaussian integers and Eisenstein-Jacobi integers are extensively studied. Decoding algorithms are proposed for these codes when up to two coordinates of a transmitted code vector are affected by errors of arbitrary Mannheim weight. Moreover, we show that the proposed codes are maximum-distance separable (MDS), with respect to the Hamming distance. The practical interest in such Mannheim-metric codes is their use in coded modulation schemes based on quadrature amplitude modulation (QAM)-type constellations, for which neither the Hamming nor the Lee metric is appropriate.

Commutative group codes in R4, R6, R8 and R16-Approaching the bound

Spherical codes in even dimensions n = 2m generated by a commutative group of orthogonal matrices can be determined by a quotient of m-dimensional lattices when the sublattice has an orthogonal basis. We discuss here the existence of orthogonal sublattices of the lattices A2, D3, D4 and E8, which have the best packing density in their dimensions, in order to generate families of commutative group codes approaching the bound presented in Siqueira and Costa (2008) [14]. © 2013 Elsevier B.V. All rights reserved.

Influence of distance, geometry and number of control stations on quality of local geodetic networks for the purpose of georeferencing of rural properties

The implementation of local geodetic networks for georeferencing of rural properties has become a requirement after publication of the Georeferencing Technical Standard by INCRA. According to this standard, the maximum distance of baselines to GNSS L1 receivers is of 20 km. Besides the length of the baseline, the geometry and the number of geodetic control stations are other factors to be considered in the implementation of geodetic networks. Thus, this research aimed to examine the influence of baseline lengths higher than the regulated limit of 20 km, the geometry and the number of control stations on quality of local geodetic networks for georeferencing, and also to demonstrate the importance of using specific tests to evaluate the solution of ambiguities and on the quality of the adjustment. The results indicated that the increasing number of control stations has improved the quality of the network, the geometry has not influenced on the quality and the baseline length has influenced on the quality; however, lengths higher than 20 km has not interrupted the implementation, with GPS L1 receiver, of the local geodetic network for the purpose of georeferencing. Also, the use of different statistical tests, both for the evaluation of the resolution of ambiguities and for the adjustment, have enabled greater clearness in analyzing the results, which allow that unsuitable observations may be eliminated.

A formalized optimum code search for q-ary trellis codes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização do perfil de deposição e do diâmetro de gotas e otimização do espaçamento entre bicos na barra de pulverização

A escolha e o uso adequado de pontas de pulverização são essenciais para a correta aplicação de produtos fitossanitários, sendo, portanto, indispensável o conhecimento de suas características. Este trabalho teve o objetivo de caracterizar o perfil de distribuição e o diâmetro de gotas, oferecendo dados para otimizar o espaçamento entre bicos na barra de pulverização. Foram avaliados os perfis de distribuição da ponta de jato plano Teejet XR 110015 VS, a 0,50 m da altura da mesa de deposição, nas pressões de 200 e 300 kPa, e o diâmetro das gotas pelo método de difração de raios laser. As distâncias máximas foram de 0,85 m, calculadas para um coeficiente de variação (C.V.) aceitável para as pressões de 200 e 300 kPa , com os respectivos valores de 9,52 e 9,58%. A distância ótima foi de aproximadamente 0,70 m, para C.V. em torno de 5%. Comparando as pressões, houve diferença significativa para DV0,1 e DV0,5, não havendo diferença para o DV0,9. Embora o aumento da pressão tenha provocado diminuição do tamanho das gotas, não houve diferença significativa de uniformidade entre as duas pressões de trabalho avaliadas. Concluiu-se que o espaçamento máximo entre bicos na barra não deverá ser maior que 0,85 m e que o DV0,5 diminui com o aumento da pressão de 200 para 300 kPa, porém sem alteração significativa da uniformidade de diâmetro de gota.

Morphological characterization and reproductive aspects in genetic variability studies of forage peanut

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Computational studies of the reversible domain swapping of p13suc1

A minimalist representation of protein structures using a Go- like potential for interactions is implemented to investigate the mechanisms of the domain swapping of p13suc1, a protein that exists in two native conformations: a monomer and a domain- swapped dimer formed by the exchange of a beta- strand. Inspired by experimental studies which showed a similarity of the transition states for folding of the monomer and the dimer, in this study we justify this similarity in molecular descriptions. When intermediates are populated in the simulations, formation of a domain- swapped dimer initiates from the ensemble of unfolded monomers, given by the fact that the dimer formation occurs at the folding/ unfolding temperature of the monomer ( T-f). It is also shown that transitions, leading to a dimer, involve the presence of two intermediates, one of them has a dimeric form and the other is monomeric; the latter is much more populated than the former. However, at temperatures lower than T-f, the population of intermediates decreases. It is argued that the two folded forms may coexist in absence of intermediates at a temperature much lower than T-f. Computational simulations enable us to find a mechanism, `` lock- and- dock'', for domain swapping of p13suc1. To explore the route toward dimer formation, the folding of unstructured monomers must be retarded by first locking one of the free ends of each chain. Then, the other free termini could follow and dock at particular regions, where most intrachain contacts are formed, and thus de. ne the transition states of the dimer. The simulations also showed that a decrease in the maximum distance between monomers increased their stability, which is explained based on confinement arguments. Although the simulations are based on models extracted from the native structure of the monomer and the dimer of p13suc1, the mechanism of the domain- swapping process could be general, not only for p13suc1.

A importância de fragmentos florestais na diversidade de anfíbios anuros em Icém, Região Noroeste do Estado de São Paulo

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

Determinação do território de forrageamento e avaliação do uso de micro porta-iscas para as saúvas Atta sexdens rubropilosa Forel, 1908 e Atta laevigata Fr. Smith, 1858 (Hymenoptera, Formicidae)

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Estudo do desempenho no salto de duas espécies de Scinax de Botucatu (Amphibia, Anura, Hylidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Utilização da distância total percorrida no teste específico de hoff como preditor da velocidade de limiar anaeróbio no futebol

OBJECTIVE: To verify the use of maximal running distance performed on Hoff test to predict the anaerobic threshold speed (sAnT). METHODS: Ten young soccer players (age of 17 ± 1 years and body mass of 64.3 ± 2.1 kg) were subjects of the study. The subjects performed 12-min test, lactate minimum test to estimate the anaerobic threshold speed and a field test called Hoff. The purpose of Hoff test was to cover the maximum distance during a period of 10min moving a soccer ball through the track by dribbling. RESULTS: The distance covered during 12-min was 2673.2 ± 64.7 m, the sAnT was 11.6 ± 0.3 km.h-1 and distance covered during test Hoff test was 1458.7 ± 49.6 m. The distance covered during Hoff test was not significantly correlated with sAnT (r = -0.20; P > 0.05) and distance covered during 12-min test (r = -0.15; P > 0.05). The sAnT did not differ of speed correspondent 90% at 12-min speed and they were statistically correlated (r = 0.65). CONCLUSION: Thus, we concluded that maximal distance covered during Hoff test cannot provides a valid prediction of the anaerobic threshold speed.

Covalent immobilization of laccase in green coconut fiber and use in clarification of apple juice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Módulo para identificação de objetos e transmissão de dados sem fio

Pós-graduação em Engenharia Elétrica - FEIS

Estudos experimentais e teórico-computacionais de novos complexos nanozeólitas-enzimas empregados na produção de biocombustíveis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pharmacokinetic Profile of Liposome-Encapsulated Ropivacaine after Maxillary Infiltration Anaesthesia

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