991 resultados para Auto-Estradas do Atlântico
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Ceramic substrates have been investigated by researchers around the world and has achieved a high interest in the scientific community, because they had high dielectric constants and excellent performance in the structures employed. Such ceramics result in miniaturized structures with dimensions well reduced and high radiation efficiency. In this work, we have used a new ceramic material called lead zinc titanate in the form of Zn0,8Pb0,2TiO3, capable of being used as a dielectric substrate in the construction of various structures of antennas. The method used in constructing the ceramic combustion synthesis was Self- Sustained High Temperature (SHS - "Self-Propagating High-Temperature Synthesis") which is defined as a process that uses highly exothermic reactions to produce various materials. Once initiated the reaction area in the reaction mixture, the heat generated is sufficient to become self-sustaining combustion in the form of a wave that propagates converting the reaction mixture into the product of interest. Were analyzed aspects of the formation of the composite Zn0,8Pb0,2TiO3 by SHS powders and characterized. The analysis consisted of determining the parameters of the reaction for the formation of the composite, as the ignition temperature and reaction mechanisms. The production of composite Zn0,8Pb0,2TiO3 by SHS performed in the laboratory, was the result of a total control of combustion temperature and after obtaining the powder began the development of ceramics. The product was obtained in the form of regular, alternating layers of porous ceramics and was obtained by uniaxial pressing. 10 The product was characterized by analysis of dilatometry, X-ray diffraction analysis and scanning electron microscopy. One of the contributions typically defined in this work is the development of a new dielectric material, nevertheless presented previously in the literature. Therefore, the structures of the antennas presented in this work consisted of new dielectric ceramics based Zn0,8Pb0,2TiO3 usually used as dielectric substrate. The materials produced were characterized in the microwave range. These are dielectrics with high relative permittivity and low loss tangent. The Ansoft HFSS, commercial program employee, using the finite element method, and was used for analysis of antennas studied in this work
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Image compress consists in represent by small amount of data, without loss a visual quality. Data compression is important when large images are used, for example satellite image. Full color digital images typically use 24 bits to specify the color of each pixel of the Images with 8 bits for each of the primary components, red, green and blue (RGB). Compress an image with three or more bands (multispectral) is fundamental to reduce the transmission time, process time and record time. Because many applications need images, that compression image data is important: medical image, satellite image, sensor etc. In this work a new compression color images method is proposed. This method is based in measure of information of each band. This technique is called by Self-Adaptive Compression (S.A.C.) and each band of image is compressed with a different threshold, for preserve information with better result. SAC do a large compression in large redundancy bands, that is, lower information and soft compression to bands with bigger amount of information. Two image transforms are used in this technique: Discrete Cosine Transform (DCT) and Principal Component Analysis (PCA). Primary step is convert data to new bands without relationship, with PCA. Later Apply DCT in each band. Data Loss is doing when a threshold discarding any coefficients. This threshold is calculated with two elements: PCA result and a parameter user. Parameters user define a compression tax. The system produce three different thresholds, one to each band of image, that is proportional of amount information. For image reconstruction is realized DCT and PCA inverse. SAC was compared with JPEG (Joint Photographic Experts Group) standard and YIQ compression and better results are obtain, in MSE (Mean Square Root). Tests shown that SAC has better quality in hard compressions. With two advantages: (a) like is adaptive is sensible to image type, that is, presents good results to divers images kinds (synthetic, landscapes, people etc., and, (b) it need only one parameters user, that is, just letter human intervention is required
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This paper presents an evaluative study about the effects of using a machine learning technique on the main features of a self-organizing and multiobjective genetic algorithm (GA). A typical GA can be seen as a search technique which is usually applied in problems involving no polynomial complexity. Originally, these algorithms were designed to create methods that seek acceptable solutions to problems where the global optimum is inaccessible or difficult to obtain. At first, the GAs considered only one evaluation function and a single objective optimization. Today, however, implementations that consider several optimization objectives simultaneously (multiobjective algorithms) are common, besides allowing the change of many components of the algorithm dynamically (self-organizing algorithms). At the same time, they are also common combinations of GAs with machine learning techniques to improve some of its characteristics of performance and use. In this work, a GA with a machine learning technique was analyzed and applied in a antenna design. We used a variant of bicubic interpolation technique, called 2D Spline, as machine learning technique to estimate the behavior of a dynamic fitness function, based on the knowledge obtained from a set of laboratory experiments. This fitness function is also called evaluation function and, it is responsible for determining the fitness degree of a candidate solution (individual), in relation to others in the same population. The algorithm can be applied in many areas, including in the field of telecommunications, as projects of antennas and frequency selective surfaces. In this particular work, the presented algorithm was developed to optimize the design of a microstrip antenna, usually used in wireless communication systems for application in Ultra-Wideband (UWB). The algorithm allowed the optimization of two variables of geometry antenna - the length (Ls) and width (Ws) a slit in the ground plane with respect to three objectives: radiated signal bandwidth, return loss and central frequency deviation. These two dimensions (Ws and Ls) are used as variables in three different interpolation functions, one Spline for each optimization objective, to compose a multiobjective and aggregate fitness function. The final result proposed by the algorithm was compared with the simulation program result and the measured result of a physical prototype of the antenna built in the laboratory. In the present study, the algorithm was analyzed with respect to their success degree in relation to four important characteristics of a self-organizing multiobjective GA: performance, flexibility, scalability and accuracy. At the end of the study, it was observed a time increase in algorithm execution in comparison to a common GA, due to the time required for the machine learning process. On the plus side, we notice a sensitive gain with respect to flexibility and accuracy of results, and a prosperous path that indicates directions to the algorithm to allow the optimization problems with "η" variables
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Self-organizing maps (SOM) are artificial neural networks widely used in the data mining field, mainly because they constitute a dimensionality reduction technique given the fixed grid of neurons associated with the network. In order to properly the partition and visualize the SOM network, the various methods available in the literature must be applied in a post-processing stage, that consists of inferring, through its neurons, relevant characteristics of the data set. In general, such processing applied to the network neurons, instead of the entire database, reduces the computational costs due to vector quantization. This work proposes a post-processing of the SOM neurons in the input and output spaces, combining visualization techniques with algorithms based on gravitational forces and the search for the shortest path with the greatest reward. Such methods take into account the connection strength between neighbouring neurons and characteristics of pattern density and distances among neurons, both associated with the position that the neurons occupy in the data space after training the network. Thus, the goal consists of defining more clearly the arrangement of the clusters present in the data. Experiments were carried out so as to evaluate the proposed methods using various artificially generated data sets, as well as real world data sets. The results obtained were compared with those from a number of well-known methods existent in the literature
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O desenvolvimento de um processo democrático de avaliação institucional na UNESP, uma universidade multi-campus, envolveu três desafios: garantir o envolvimento de grupos representativos da comunidade no processo de avaliação; atribuir poder e responsabilidade a cada setor acadêmico e administrativo no processo de avaliação; criar uma cultura de auto-avaliação e reflexão que possibilitasse debate crítico e auto-gestão dos projetos acadêmicos. Com base nos termos de referência estabelecidos pela comunidade a CPA desenvolveu uma metodologia de avaliação democrática e investigativa, orientada para a auto-gestão e de natureza quali-quantitativa. Fundamentada em três enfoques teóricos de avaliação, o democrático, o de tomada de decisão e o crítico o processo envolveu três funções: a diagnóstica, a formativo-reflexiva e a de revisão crítica. Atualmente os usos dos resultados da avaliação para orientar políticas e decisões acadêmicas, especialmente nos cursos de graduação, evidenciam avanços no processo de internalização de cultura de avaliação orientada para auto-gestão.
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Este artigo trata da configuração de uma rede intelectual de dimensão internacional que uniu a América Latina e a Península Ibérica, a partir de meados do século XIX. Objetivamos analisar o papel dos intelectuais e órgãos de imprensa na formação dessa rede e discutir suas idéias e projetos, à luz do contexto político e do debate cultural. Consideramos que a ação dos intelectuais e da imprensa contribuiu para a configuração de um espaço singular de circulação de idéias e de formação de uma opinião pública ibero-americana.
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This dissertation, entitled O Auto da Morte e da Vida: A escrita barroca de João Cabral de Melo Neto, has the aim of analising, interpreting, in a baroque perspective, Cabral s writing in the poem/play Morte e vida severina Auto de Natal Pernambucano, taking as basis the theories of Eugênio D´Ors, Severo Sarduy, Omar Calabrase, Lezama Lima, Afonso Ávila, Affonso Romano de Sant´Anna and others cited in the body of this work. During the analisys we feature confluences, relations, similarities, identification between the Baroque of the counter reformation and the modern Baroque or Neobaroque. We seek to comprehend the baroque which is new in the XX century and Cabral s poetry as an element of the contemporaneity, by updating the concept of the Baroque in the 1600s, when it is detected in its purest characteristic in human relation (the life of the Northwestern brazilian) through an intangible reality (the death). The Baroque as a cultural summary of a period of instability and transformation, with the power of dismantling an already established poetry. The fight between words and things, language and reality
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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This study approach the Jorge Luis Borges s prose of fiction under the perspective of mimesis and the self-reflexivity. The hypothesis is that the Aleph is a central symbol of the Borges s fictional universe. The rewriting and the retake of this symbol along of his work entail to a reflection about the possibilities and the limits of mimesis. This study is divided in three parts which contain two chapters. The first part Bibliographic revision and conceptual fundaments of inquiry discuss the critical fortune of author (Chapter 1) and the concepts that will give sustentation to the inquiry (Chapter 2). The second part About the Borges s aesthetic project sketch out the literary project defended by Borges that is his conception of the literature and his ideological matrix (Chapter 3) beside his anti-psychologism and his nostalgia of epos (Chapter 4). The third and last part is entitled The Aleph and his doubles. In the chapter 5 this study analyses the short story El Aleph and consider its centrality on the Borges s work. The argument that is on this short story Borges elaborates a reflection about mimesis. In the chapter 6, on the same hand, four short stories will be analysed: Funes el memorioso ; El Libro de Arena ; El evangelio según Marcos and Del rigor en la ciencia . The conclusion that is the Borges s literature is self-awake of its process as such demonstrate its parodic sense and its bookish origin. Hence, the Borges s literature overlapping the mimetic crisis of language and challenge the limits between fiction and reality. However, it doesn t surrender to the nihilist perspective that is closing of literature to the world
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This work is a detailed study of self-similar models for the expansion of extragalactic radio sources. A review is made of the definitions of AGN, the unified model is discussed and the main characteristics of double radio sources are examined. Three classification schemes are outlined and the self-similar models found in the literature are studied in detail. A self-similar model is proposed that represents a generalization of the models found in the literature. In this model, the area of the head of the jet varies with the size of the jet with a power law with an exponent γ. The atmosphere has a variable density that may or may not be spherically symmetric and it is taken into account the time variation of the cinematic luminosity of the jet according to a power law with an exponent h. It is possible to show that models Type I, II and III are particular cases of the general model and one also discusses the evolution of the sources radio luminosity. One compares the evolutionary curves of the general model with the particular cases and with the observational data in a P-D diagram. The results show that the model allows a better agreement with the observations depending on the appropriate choice of the model parameters.
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The aging process modifies various systems in the body, leading to changes in mobility, balance and muscle strength. This can cause a drop in the elderly, or not changing the perceived self-efficacy in preventing falls. Objective: To compare the mobility, body balance and muscle performance according to self-efficacy for falls in community-dwelling elderly. Methods: A cross-sectional comparative study with 63 older (65-80 years) community. Were evaluated for identification data and sociodemographic, cognitive screening using the Mini Mental State Examination (MMSE), effective for the fall of Falls Efficacy Scale International Brazil (FES-I-BRAZIL), Mobility through the Timed Up and Go Test , the balance Berg Balance Scale (BBS) and the Modified Clinical Test tests of Sensory Interaction on Balance (mCTSIB), tandem walk (TW) and Sit to Stand (STS) of the Balance Master® System. Finally, muscle performance by using isokinetic dynamometry. Statistical analysis was performed Student t test for comparison between groups, with p value ≤ 0.05. Results: Comparing the elderly with low-efficacy for falls with high-efficacy for falls, we found significant differences only for the variable Timed Up and Go Test (p = 0.04). With regard to data on balance tests were significant differences in the speed of oscillation firm surface eyes open modified Clinical Test of Sensory Interaction on Test of Balance (p = 0.01). Variables to isokinetic dynamometry were no significant differences in movement knee extension, as regards the variables peak torque (p = 0.04) and power (p = 0.03). Conclusion: The results suggest that, compared to older community with low-and high-efficacy for falls, we observed differences in variables related to mobility, balance and muscle function
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The Anguiliformes is constituted by 15 families, 141 sorts and 737 species. In this group eight families possess at least one karyotyped species, where a prevalence of karyotypes with 2n=38 is evidenced chromosomes and high NF, apparently basal for the Anguiliformes. The only family who shows a different karyotypic pattern from the others is the Muraenidae family. In this, of the eight species already described, all of them present 2n=42 chromosomes. Despite the dimension of this Order, few species present karyotypics descriptions. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n=38, 8m+14sm+10st+6a, NF=70) and three species of Muraenidae, Enchelycore nigricans (2n=42, 6m+8sm+12st+16a, NF=68), Gymnothorax miliaris (2n=42, 14m+18sm+10st, NF=84), Gymnothorax vicinus (2n=42, 8m+6sm+28a, NF=56) and Muraena pavonina (2n=42, 6m+4sm+32a, NF=52), collected in the coast of the Rio Grande do Norte state, Saint Peter and Paul Rocks and in the coast of Bahia state were analyzed. Mitotics chromosomes had been gotten through mitotic stimulation with yeasts. Among the analyzed species, it is observed the presence of characteristic large metacentric chromosomic pairs (≅10µm). As for the structural standard, heterochromatics regions in these species in centromeric position of the majority of the chromosomic pairs and simple ribosomal sites had been evidenced. For the Ophichthidae family, the gotten data corroborate the hypothesis of karyotypic diversification mediated by the occurrence of pericentrics inversions and robertsonians rearrangements, while in the Muraenidae, the identification of larger chromosomic values (2n=42), suggests derived karyotypes, possibly caused by possible chromosomic fissions
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This work broaches the participation of the Jewish community in the urban expansion of Recife, Brazil, during the Dutch period (1630-1654). With the arrival of the Dutch, the village of Olinda, former capital of Pernambuco, was destroyed and Recife received the juridical statute of city (stad), becoming the capital of Dutch Brazil or New Holland. It became the main West Indians Company s entrepot in South Atlantic, serving as naval base, port of call for ships, and point of export of the sugar production of Pernambuco, and import of European goods and African slaves. In order to such administrative, military and economic functions be carried out, the sand isthmus where Recife used to stay, and the fluvial island of Antônio Vaz, received improvements of many sort. The Dutch hydraulic technology was put in practice, with a posture of opposition between civilization and nature. Among military works and production of urban equipments, the rivers shores were land-filled, canals were built, bridges were lifted, and hundreds of buildings were erected. The civil Dutch population of Recife engaged in the process of production of physical space, which brought a sense of collective action towards the formation of the urban, or burgher, community. From the physical to the social space, there was an effort towards Dutch cultural standards in the urban environment. The Zur Israel Jewish community, formed by private civilians, it is, nonemployees of the WIC, engaged in those processes. It produced physical space through the land-filling and improvement of non healthy areas, and was also responsible for the construction of a significant section of the town s buildings and some of urban equipments, such as stores, markets and slave-warehouses, making more dynamic their economical activities. But their social traffic was due to the adaptation of their behavior to the standards of Dutch sociability. Thus, the community body made itself part of the social body. Disposing of internal selfregulation, it produced spaces with their cultural references cemetery, synagogue, texts enjoying benefits of the government. Zur Israel inscribed itself in the universal history of the Jews as the first community of Americas, and had a fundamental part on the emancipation of Jews within Western society
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The present study investigated the reproductive dynamics and parasitism of four species of marine fishes: serra Spanish mackerel, Scomberomorus brasiliensis, Atlantic leatherjacks, Oligoplites saurus and O. palometa,, and Atlantic bumper, C. chrysurus, during the period of August, 2005 to July, 2007, in the coastal waters of Southwest Atlantic Ocean, Brazil. The collected fish samples were measured, weighed, dissected, the gonads were weighed and examined to separate the sex. The gonadosomatic index (GSI), fecundity, type of spawning, the breeding season, the macro and microscopic characterization of the gonads were determined. The ectoparasites from the branchial chambers and bucal cavity of the fish were collected, measured, weighed and identified. The sex ratio of the study fish species were approximately 1M:1F, however, there was a predominance of males of O. palometa (3M:2F). The GSI of fishes varied according to their reproductive cycle and the stage of gonadal maturation. The highest values of GSI and the spawning period coincided with the rainy period of the region. The females presented total spawning and the fecundity was positively correlated with the weight of the ovary and the body. Four stages of development of the gonads immature, maturing, mature and spent were identified macroscopically and histological analyses of ovaries revealed the different phases of oocyte development. Three species of isopod parasites were identified in the study fishes: Livoneca redmmanni, Rocinela signata and Cimothoa spinipalpa. The first two species occurred in the branchial cavities of C. chrysurus and S. brasiliensis. The isopod C.spinipalpa (a new species) was registered for the first time in the bucal cavity of O. saurus and O. palometa. The parasitic isopods preferred the branchial chambers and the bucal cavity of the host fishes as these were protected microhabitats. The isopods parasitized the immature, maturing and mature fishes. The prevalence of infection of isopods in the hosts varied from 16 to 21%, though in O. palometa it was 60%. In the rainy period the highest isopod parasitic occurrence was registered, however, this did not prejudice the normal reproductive cycle of the host fish.
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The objective of this work was to evaluate the buffering effect of sodium bicarbonate (NaHCO3), used in the levels of: 0, 0.7, 1.4 and 2.1% of dry matter, on the in situ degradation of corn and cottonseed meal. A diet with 60% autohidrolised sugar bagasse (BAH) and 40% of concentrate was used, plus urea, minerals and limestone. The rations was calculated to allow 300g of daily gain. After 20 days of adaptation to the treatment (levels of NaHCO3), 5g of each feed was incubated in the rumen of four bovines for 3, 6, 12, 24 and 48 hours, using naylon bag with size of 7,5 x 17,5 cm with pores of 36 micras. A randomized blocks design with four treatment (levels of NaHCO3) were used. The buffer affected the in situ dry matter degradation, whose means were 49.68; 63,10; 67,71; and 60,85% and 25.89; 30.88; 33.48 and; 31.02% for the corn and cottonseed meal, respectively. The level of 1.4% of NaHCO3 provided the highest value of degradability, which did not differ from the 0.7% and 2.1% levels, for the corn. The degradability of protein was not affected by the treatments.