Os três problemas clássicos da Matemática grega

Pós-graduação em Matemática em Rede Nacional - IBILCE

Construções euclidianas e o desfecho de problemas famosos da geometria

Construction techniques with ruler and the compasses, fundamental on Euclidean geometry, have been related to modern algebraic theories such as solving equations and extension of bodies from the works by Paolo Ruffini (1765-1822), Niels Henrik Abel (1802-1829) and Evariste Galois (1811-1832). This relation could provide an answer to some famous problems, from ancient Greece, such as doubling the cube, the trisection Angle, the Quadrature of the Circle and the construction of regular polygons, which remained unsolved for over two thousand years. Also important for our purposes are the notions of algebraic numbers, transcendental and the criteria for constructability, of those numbers. The objective of this study is to reconstruct relevant steps of geometric constructions with ruler (unmarked) and the compasses, from the elementary to the outcome buildings, in the nineteenth century, considering those mentioned problems.

Estudo da influência do agente nucleante )ALTi5%B1%) na microestrutura de chapas AA8011 obtidas por lingotamento contínuo

The aluminum includes several properties with excellent relation between weight and mechanical resistance. With technological advances, increasingly demand the development of new alloys and other production processes in order to reduce the cost of production and insert these new alloys in broader applications. The process of continuous caster (TRC promoted the unite of the aluminum smelting process with the first stage of rolling, making it most economical through the merger these two phases besides transform the continuous casting process. The AA8xxx series is one of the most versatile aluminum alloys and the most often used in continuous caster process provided a great potential application in the market. In order to further, optimize the process it is necessary to increase awareness of the aluminum solidification phenomena associated with the addition of grain refiner, and control of some aluminum production parameters in the process (production rate, metal temperature, etc.). In this study, AA8011 alloy samples were taken in the raw state obtained by the continuous casting process. The samples were laminated to a thickness of 7mm during the process itself and analyzed at three points along its width by microstructural analysis throughout its thickness, the variation rate of addition of the grain refiner in order to assess the influence of this addition with crystallographic formation and some formation of intermetallic precipitates during the solidification. Through this work, it was possible to improve the knowledge related to the addition of refiner with the monitoring of these production processes

Screening of Conditions for the Preparation of Poly( -Caprolactone) Nanocapsules Containing the Local Anesthetic Articaine

The local anesthetic articaine (ATC) is widely used in dentistry; however, its side effects can include paresthesia and nerve injury. Polymeric nanocapsules (PN) can be used as carriers for drugs, and help to reduce undesirable symptoms. The objective of this study was to evaluate the influence of different factors on the average size, polydispersion, and encapsulation efficiency of PN containing ATC. Poly(ε-caprolactone) (PCL) nanocapsules containing ATC were prepared by the oil-in-water emulsion/solvent evaporation method. The final ATC concentration was 2%. The preparation conditions were optimized using a central composite blocked cube-star design to investigate the influence of two variables at five levels, with 22 factorial points (–1 and +1), two replicates of the central point, 2×2 axial points (–1.414 and +1.414), and an orthogonal distribution, resulting in 10 experiments. The factors varied were the PVA concentration and the sonication time. The nanocapsules showed a satisfactory size range, a polydispersivity index less than 0.2, and high encapsulation efficiency. The values of the factors had no significant influence on either average size or polydispersion, although the encapsulation efficiency was significantly influenced by the sonication time. Improved formulations were identified using the central composite design, which revealed that the main consideration in selecting a suitable formulation was the encapsulation efficiency. Two of the formulations showed both high encapsulation efficiency and colloidal characteristics appropriate for the route of administration.

Synthesis and characterization of NaNbO3 mesostructure by a microwave-assisted hydrothermal method

In the present work, we report the synthesis and characterization of NaNbO3 particles obtained by microwave-assisted hydrothermal method from Nb2O5 and NaOH. The synthesis was made at different periods at 180 °C and 300W. The crystallization of NaNbO3 structures produced Na2Nb2O6.H2O in the intermediate phase with fiber-like morphology, and this is associated with the synthesis time. Pure orthorhombic NaNbO3 with cube-like morphology originates after synthesizing for 240 minutes. To verify the remnant polarization of particles, films were obtained by electrophoresis process and sintered at 800°C for 10 minutes in a microwave furnace. The films characterization indicated that films of niobate with fiber-like morphology present remaining polarization, and the morphology of cubes did not show remaining polarization. Considering these results, it can be concluded that the morphology implemented ferroelectric property of NaNbO3.

O poético alinhave de Murilo Mendes: o poeta, a musa e a metapoesia em As Metamorfoses

Lying under the contribution of a display of characteristics with multiple meanings (Catholicism, Surrealism, unite of contraries, and the dialogue with other types of art), Murilo Mendes focalizes some subjects that are made to become appealing in his works. Some of these subjects appear in his 1945’s poetry book, As metamorfoses, the object of analysis in this present work: the poet’s figure, insert in the historical view of the World War II and by the poet devastated; the muse’s figure, carrier of the sacred and the profane, whose body represents a repository of descriptions with surrealistic meanings, that is shown indistinctly as the poetry itself; and, concluding, the poetry (or the metapoetry) expressed in this context (historical and literary). Therefore, we intend to search, based in the analysis of poems, how each of this instances are configured inside the poetic universe of Murilo Mendes, with the intention of enlighten the constitution of the sewing made of them by the poet from Juiz de Fora; instances that are very precious when we deal with the poetry that gives to his writings the patent feature of modernity.

Metamorfose: reflexões sobre o pensamento de Ignacio Assis Silva ou tentando achar o fio da meada

This text, homage to Ignacio Assis Silva, looks for the founding theoretical conceptions of his thoughts. When I looked at his texts, from the 70’s to the 90’s, my reading went through the path of an author who is always worried about revealing the birthplace of meaning. To catch this unique moment of semiosis, Silva proposes the concept of metamorphosis, a key-term which allows us to unite the two ends of his formation: Historical Grammar and Semiotic

Desenvolvimento de uma aplicação para suporte ao t-learning

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

Sobre Villiers de l'Isle-Adam e seus contos cruéis

Villiers de l’Isle-Adam (1838-1889) is always remembered and admired for his books: Contes cruels, L’Ève future and Claire Lenoir- which summarize the main worries of the writer, his satire of the triumphant Positivism, his metaphysical theory and his aspiration for the Ideal. He is one of the greatest artisans of the French literature style of the XIX century and, in spite of some individual and particular characteristics, he shares with other writers from his time – Joris-Karl Huysmans, Barbey d’Aurevilly, Leon Bloy, among others – the same sorrow and fury towards Positivism and Mercantilism. Having as a starting point the collection Contes cruels, the purpose of this article is to reveal the author’s writings who, by searching for the Ideal and by taking refuge in art, is able to unite the poet, the ironic and the idealist philosopher. Through his writings, the writer moves away from the world’s mediocrity and can express a mix of revolt, reaction, rebellion and also, his hopes expressed in his beliefs in the “Au-delà” and in the salvation by the Ideal.

On energy harvesting form time-limited excitations: simulations and case study

Linear resonant harvesters have been the most common type of generators used to scavenge energy from mechanical vibrations. When subject to harmonic excitation, good performance is achieved once the device is tuned so that its natural frequency coincides with the excitation frequency. In such a situation, the average power harvested in a cycle is proportional to the cube of the excitation frequency and inversely proportional to the suspension damping, which is sought to be very low. However, a very low damping involves a relatively long transient in the system response, where the classical formulation adopted for steady-state regimes do not hold. This paper presents an investigation into the design of a linear resonant harvester to scavenge energy from time-limited harmonic excitations involving a transient response, which could be more likely in some practical situations. An application is presented considering train-induced vibrations.

Compact setup for reflection holography with Bi12TiO 20 crystals

A novel optical setup for imaging through reflection holography with Bi12TiO20 (BTO) sillenite photorefractive crystals is proposed. Aiming a compact, robust and simple optical setup the lensless Denisiuk arrangement was chosen, using a He-Ne red laser as light source. In this setup the holographic medium is placed between the light source and the object. The beam impinging the crystal front face is the reference one, while the light scattered by the surface is the object beam in a holographic recording by diffusion. In order to allow the readout of the diffracted wave only and to keep the setup simplicity a polarizing beam splitter cube (PBS) was positioned at the BTO input. The reference beam is s-polarized (polarization direction perpendicular to the table top) and the crystal. 〈001〉-axis is rotated by an angle γ with respect to the input polarization in order to make the transmitted object beam and the diffracted beam to have orthogonal polarizations. While the transmitted wave is reflected by the PBS at a right angle, the diffracted wave carrying the holographic reconstruction of the object passes through the PBS, being collected by a positive lens in order to form the holographic image at a CCD camera. The holographic recording with the grating vector is parallel to the 〈100〉-axis. An expression for the diffracted wave intensity as a function of γ was derived, and this relation was experimentally investigated. © 2008 American Institute of Physics.

Religiosidade e mito na obra de José Carlos Mariátegui e a teologia da libertação

Pós-graduação em Ciências Sociais - FCLAR

Obtenção e caracterização de nanofibras eletrofiadas via solução de quitosana com e sem inclusão de hidroxiapatita

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Origami: o uso como instrumento alternativo no ensino da geometria

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise de projetos arquitetônicos modernistas com interferências visuais no Brasil

Modernism was a movement that began in the 1920s through the critical activities of Oswald de Andrade, Menotti del Picchia, Mário de Andrade and others who warned of the valuation of national roots. Thus exposed their ideas renewing groups of artists who begin to unite around a new aesthetic proposal. Modern architecture in Brazil had its origins in European avant-garde in the early twentieth century as well, represented by architect Antonio Moya. In 1923 arrives in São Paulo Warchavchik the architect, who always insisted on the same character "modern" time and "Brazil" in its architecture. Years following: architects claim in full, influencing young architects. This research aims to analyze the projects executed by some architects that have reshaped or rewrote the architecture in Brazil with modernism and artistic / visual interference with paneled walls and details entered in these buildings.