Otimização de superfícies seletivas de frequência com elementos pré-fractais utilizando rede neural MLP e algoritmos de busca populacional

This thesis describes design methodologies for frequency selective surfaces (FSSs) composed of periodic arrays of pre-fractals metallic patches on single-layer dielectrics (FR4, RT/duroid). Shapes presented by Sierpinski island and T fractal geometries are exploited to the simple design of efficient band-stop spatial filters with applications in the range of microwaves. Initial results are discussed in terms of the electromagnetic effect resulting from the variation of parameters such as, fractal iteration number (or fractal level), fractal iteration factor, and periodicity of FSS, depending on the used pre-fractal element (Sierpinski island or T fractal). The transmission properties of these proposed periodic arrays are investigated through simulations performed by Ansoft DesignerTM and Ansoft HFSSTM commercial softwares that run full-wave methods. To validate the employed methodology, FSS prototypes are selected for fabrication and measurement. The obtained results point to interesting features for FSS spatial filters: compactness, with high values of frequency compression factor; as well as stable frequency responses at oblique incidence of plane waves. This thesis also approaches, as it main focus, the application of an alternative electromagnetic (EM) optimization technique for analysis and synthesis of FSSs with fractal motifs. In application examples of this technique, Vicsek and Sierpinski pre-fractal elements are used in the optimal design of FSS structures. Based on computational intelligence tools, the proposed technique overcomes the high computational cost associated to the full-wave parametric analyzes. To this end, fast and accurate multilayer perceptron (MLP) neural network models are developed using different parameters as design input variables. These neural network models aim to calculate the cost function in the iterations of population-based search algorithms. Continuous genetic algorithm (GA), particle swarm optimization (PSO), and bees algorithm (BA) are used for FSSs optimization with specific resonant frequency and bandwidth. The performance of these algorithms is compared in terms of computational cost and numerical convergence. Consistent results can be verified by the excellent agreement obtained between simulations and measurements related to FSS prototypes built with a given fractal iteration

A melancolia nas crônicas de Maria Judite de Carvalho

Maria Judite de Carvalho began his literature in 1949 in journals of Lusitanian capital. Until his death, which occurred in 1998, published more a thousand texts, most of them have never been extracted from their support original, the newspaper, making them unknown to the public today. In order to rescue of this precious material chosen as the literary corpus of Search the chronicles published in the Diário de Lisboa, periodic where the writer published the largest number of texts in the section Rectângulos da Vida, 395 (three hundred and ninety-five) chronic for five consecutive years (1968-1972). Looking at these texts I realized that she inserted into her narrative the changes occurred in the twentieth century, in Portugal, capturing the moment of breaking with traditional models and introducing new paradigms imposed by modernity. What happens in this period is an extremely fast and deep change of values and customs with which the Portuguese society faces and experiences with a certain uneasiness. Given this unstable scenario, Maria Judite expresses, through her ironic and critical narrative, the portrait of the Portuguese people and their behavior full of anguish and sorrows that are revealed through the gloom. After a thorough reading of his texts I found that this was the guiding element of juditiana writing. It is presented in the chronicles in many respects they were privileged during the five years of publications they are loneliness, abandonment, death, isolation of individuals who feel increasingly powerless in the face of changes experienced as a consequence of this state and present is melancholy all the time. This is a photograph of Maria Judite de Carvalho on Portuguese society told in her chronicles as I saw this survey.

Produção em revista : Representação do moderno e do regional na experiência potiguar anos 1920

This work brings some reading about a few Norte-rio-grandenses writers collaborations published in literary papers which circulated during the third decade of the twentieth century in Brazil, in a way of enlarging the understanding of how the cultural debate was carried out in the years of the definition of the Brazilian Modernism, based on the relationships between literature and culture. Under the genres of prose and poetry, the selected textual collaborations for analysis have brought the traces of a small group of articulated authors in the Brazilian cultural scenery from the 1920 s, concerning the issues of the modern (linked to the modernist renovation) and the regional (under the aspects of the tradition). The set of the analyzed collaborations is representative of a modern-regional cultural practice marked by a tendency either local or cosmopolitan, thus, sharing a large dimension of the formation of the modern literary tradition, marked by different kinds of practices which give form to the project of a collective national awareness. The characterization of the existence of an intellectual field with big links, however with its own characteristics and a certain autonomy, which also gets integrated to the cultural debate of the so-called modernist years through the literary vehicles, gives to these intellectual people a co-participation in the renewing movement in the formation context of the brazilian cultural modernity of the early twentieth century

Propriedades magnéticas de nanopartículas de ferro em substratos antiferromagnéticos

The effect of finite size on the magnetic properties of ferromagnetic particles systems is a recurrent subject. One of the aspects wide investigated is the superparamagnetic limit where the temperature destroys the magnetic order of ferromagnetic small particles. Above the block temperature the thermal value of the magnetic moment of the particle vanishes, due to thermal fluctuations. The value of the blocking temperature diminishes when the size of the particle is reduced, reflecting the reduction of the anisotropy energy barrier between the uniform states along the uniaxial axis. The increasing demand for high density magnetic media has recently attracted great research interest in periodic arrangements of nanometric ferromagnetics particles, approach in the superparamagnetic limit. An interesting conjecture is the possibility of stabilization of the magnetic order of small ferromagnetic particles (F) by interface coupling with antiferromagnetic (AF) substrate. These F/AF systems may also help to elucidate some details of the effect of exchange bias, because the effect of interface roughness and the paper of domain walls, either in the substrate or the particle, are significantly reduced. We investigate the magnetic phases of small ferromagnetic particles on a antiferromagnetic substrate. We use a self-consistent local field method, incorporating the interface field and the dipole interaction between the spins of the ferromagnetic particle. Our results indicate that increasing the area of the interface favors the formation of the uniform state. Howere above a critical height value appears a state non-uniform is formed where the spins of in the particle s free surface are rotated with respect to the interface spins direction. We discuss the impact of the competition between the dipolar and interface field on the magnetic charge, that controls the field of flux leakage of the particle, and on the format of the hysteresis curves. Our results indicate that the liquid magnetic charge is not a monotonically increasing function of the height of the particle. The exchange bias may display anomalous features, induced for the dipolar field of the spins near the F/AF interface

Espectro das ondas de spin lineares e não-lineares em multicamadas magnéticas anisotrópicas

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Excitações em cristais fotônicos unidimensionais

In this work, we present a theoretical study of the propagation of electromagnetic waves in multilayer structures called Photonic Crystals. For this purpose, we investigate the phonon-polariton band gaps in periodic and quasi-periodic (Fibonacci-type) multilayers made up of both positive and negative refractive index materials in the terahertz (THz) region. The behavior of the polaritonic band gaps as a function of the multilayer period is investigated systematically. We use a theoretical model based on the formalism of transfer matrix in order to simplify the algebra involved in obtaining the dispersion relation of phonon-polaritons (bulk and surface modes). We also present a quantitative analysis of the results, pointing out the distribution of the allowed polaritonic bandwidths for high Fibonacci generations, which gives good insight about their localization and power laws. We calculate the emittance spectrum of the electromagnetic radiation, in THZ frequency, normally and obliquely incident (s and p polarized modes) on a one-dimensional multilayer structure composed of positive and negative refractive index materials organized periodically and quasi-periodically. We model the negative refractive index material by a effective medium whose electric permittivity is characterized by a phonon-polariton frequency dependent dielectric function, while for the magnetic permeability we have a Drude like frequency-dependent function. Similarity to the one-dimensional photonic crystal, this layered effective medium, called polaritonic Crystals, allow us the control of the electromagnetic propagation, generating regions named polaritonic bandgap. The emittance spectra are determined by means of a well known theoretical model based on Kirchoff s second law, together with a transfer matrix formalism. Our results shows that the omnidirectional band gaps will appear in the THz regime, in a well defined interval, that are independent of polarization in periodic case as well as in quasiperiodic case

As praças de cultura no governo Djalma Maranhão

Le présent texte vise à analiser la apropriation de l'espace par le pouvoir publique. Entre les années 1956 et 1964, la ville brésilien de Natal a été administré par le maire Djalma Maranhao, dirigeants politiques marquées par des idées nationalistes, comme la lutte contre l'impérialisme et l'émancipation du peuple a travers de ce que l'on appelle « culture populaire ». Le terme a acquis une connotation politique, en même temps dans ce qui était considéré comme la plus pure manifestation du peuple brésilien. La dynamique politique signifie aussi un nouveau regard sur la ville, enquant que le désir de progrès, de industrialisation et de réformes sociales propagée dans la politique nationale brésilienne, directement traduit par des changements dans son espace physique. Dans cette orientation nationaliste, la ville a entrepris des actions systématiques à l'encontre des nouveaux besoins urbains qui se posent en même temps que tourné certains places de la ville à espaces culturelles, appelée « places de la culture ». Ces espaces sont destinés à la promotion de la culture populaire en même temps il a été un domaine stratégique de la production et la réception des valeurs défendues par Djalma Maranhao. En ce sens, nous avons demandé répondre quelle a été la position du maire face à la besoins urbaines qu'ils se posaient et comme les places de la culture sont intégré à la vie quotidienne de la ville de Natal, donnant une nouvelle signification à la place publique. Pour la construction de ce travail, nous utilisons les sources orales et de revues, de journaux et de A República et Folha da Tarde, comme le principal ressources méthodologiques

Habitação e modernização: Cidade Nova e maneiras de viver em Natal no início do século XX

Analyses the presence of new standards of habitation detected in the construction of the region called Cidade Nova, in the first s years of the XX century. Associates the presence of these new patterns with the historical moment lived by the capital, marked by the urban modernization and by the changes of local life. Map voices that, introduced by the republican groups since 1889, pronounced the overcome of the old city of the XIX century asseverated a new model of town. Make use, as fundamental fonts of research, of the urban chronicles produced by the local intellectuals and the newspapers, like A República. Dialog with chronics that includes since propositions about the colonial past until the preoccupations about the acting of the State on how to order the public space. Identifies on those texts the political motivations and the elements whose where inherent to capitalism that accelerated the changes occurred in the urban space. Demonstrates the gradual occupation of Cidade Nova as an important modification happened in the city from that time on. That neighborhood adopted a new model on how to construct the houses of their citizens and helped to promote the urban life as a whole. From now on, Natal has a space meant for the home of their richest families. Recognizes, from many ways, many discourses, manners of living that was legitimized by the changing of the XIX to the XX century and has his highest point in the 1920´s. And it was representative of the strong attachment about the habits of refinery and order in the essence of the private life of the local urban elites

Maus ares e malária: entre os pântanos de Natal e o feroz mosquito africano (1892-1932)

The development of epidemiological practices in the last years of the nineteenth and early twentieth century was characterized by both an influence of medical geography and the emergence of microbes and vectors of diseases. Both theories were used to explain outbreaks in Rio Grande do Norte specially in Natal. In this process were organized new institutions linked to public health, unhealthy spaces and prescribed hygiene measures. The redefinitions of the spaces were linked to updated elements of Hippocratic medicine such as aerism and emphasis on medical topography. How the physicians of the town were organized in the face of new meanings and fields of expertise in the demarcation of diseases and regulation of their own practices against the illegal medical practitioners? Likewise, the very occurrence of epidemics mobilized people, urban institutions and apparatuses. But how the Hippocratic legacy that leads to the idea of bad air originated by swamps from the eighteenth and nineteenth century has been linked to new microbial assumptions and disease vectors in the early twentieth century? How an invader from Africa, (the mosquito A. gambiae) mobilized transnational efforts to combat malaria and redefined the epidemiological practices? The aim of this work is to understand how epidemiological practices redefine the way we define spaces, practices and disease from both an approach influenced by a relational history of spaces and a theoretical synergy which includes topics in Science Studies, Post Structuralist Geography and some elements of Feminist Studies. Documentary research were surveyed in the reports of the provincial presidents, government posts to the Provincial Assembly, specialized medical articles and theses, and documents from the Rockefeller Foundation and national and international journals. In this regard shall be given to both material and discursive aspects of space-related practical epidemiological that Natal as much (in general) Rio Grande do Norte between bad air and malaria.

Relação entre padrão comportamental, estágios do ciclo de muda e atividade de enzimas digestivas proteolíticas em juvenis do camarão marinho Litopenaeus vannamei (Crustacea: Penaeidae)

Shrimp farming in Brazil is a consolidated activity, having brought economical and social gains to several states with the largest production concentrated in the northeast. This fact is also reflected in higher feed intake, necessitating a more efficient feed management. Currently, management techniques already foresee food loss due to molting. In this sense, studies relating shrimp s digestive physiology, molting physiology and behavioral response of shrimp feed can optimize the feed management. Thus, our study aimed to evaluate the behavioral response of the marine shrimp L. vannamei (Crustacea: Penaeidae) in accordance with the stages of moulting cycle and feeding schedules based on higher or lower activity of proteolytic digestive enzymes; also, to investigate the influence of feeding schedule on hepatosomatic index and non-specific and specific protease activity (trypsin). Experiments were carried out at the Laboratory of Shrimp Behavioral Studies at UFRN in partnership with the Laboratory of Enzimology UFPE. Juveniles of L. vannamei weighting 5.25 g (+ 0.25 g) were kept in aquaria at a density of 33 shrimp m -2. In the first experiment, shrimp were fed in the light phase or in the dark phase for 8 days; in the ninth day, the animals were observed for 15 minutes every hour during the 12 hours of each phase of the photoperiod. We recorded the frequency of inactivity, exploration, food intake, burrowing, swimming and crawling behavior. At the end of the 12th observation session, the shrimp were sacrified and classified by the method of setogenesis in the molt cycle stages A, B, C, D0, D1, D2 or D3. We found that the shrimp in A stage show high levels of inactivity. Moreover, the frequency of food intake was very low. The shrimp in D3 stage also had low food intake and high inactivity associated with elevated frequencies of burrowing. In the second experiment, shrimp were kept in physiological acclimation to experimental conditions for 28 days, distributed in 12 treatments in the light phase and 12 treatments in the dark phase. In the end, the animals were sacrified and dissected to assess non-specific and specific protease activity (trypsin) activity. In general, these parameters did not vary among animals fed in the light phase and those fed in the dark phase. However, significant differences were found in the activity of specific and nonspecific proteases in relation to food treatment. In the light phase, the major proteolytic activities converged to 10 hours after the start of the light phase, while the lowest activities converged to 6 hours after the beginning of this phase. In the dark phase, the highest enzyme activity converged to 12 hours after the onset of phase, while the lowest activities converged to 3 hours after the onset of phase. In the third experiment, we sought to evaluate the behavioral responses of shrimp in relation to dietary treatments based on higher or lower activity of proteolytic enzymes, considering the results of the second experiment. The behavioral categories observed were the same as the ones in the first experiment, with observations of 30 minutes (15min before and 15min after food supply). We found variation in behavioral responses as a function of the treatments, with greater intake of food in shrimp fed during the period of greatest activity of proteolytic enzymes, in the light phase. Thus we see that periodic events associated with the shrimp s physiology interfere in their behavioral responses, revealing situations that are more adjustable to the provision of food, and consequently optimizing feeding management

Exploração sexual comercial de crianças e adolescentes : o estado da arte nas produções acadêmicas em psicologia

The Commercial Sexual Exploitation of Children and Adolescents (ESCCA) is a phenomenon that has been given priority in public policy agenda of many democratic governments of Western countries and civil sectors of society, besides the object of studies in different fields of knowledge. Psychology is among these areas and is considered one of the references in the construction of knowledge and actions to confront the phenomenon. However, the epistemological foundations of psychological science are quite different, and so, several are his speeches, knowledge produced and ways of conceiving man and the world. This is evident in the publications of psychology on ESCCA. This work aims to achieve a state of the art of psychology publication in Brazil (in the post-graduation - through theses and dissertations - and journals) on the Commercial Sexual Exploitation of Children and Adolescents. More specifically try to evidence (a) what conceptions of commercial sexual exploitation of children and adolescents the authors lists, (b) what are aimed at research and publications, (c) how the research and issues are justified, and (d) that theoretical approaches the authors are affiliated and methodological possibilities are applied to range the aim proposed in their work. In order to do so, a survey was conducted in the major index sites (eg, BVS-Psi, Capes, theses and dissertations database of university libraries) of the material, covering the period 1990 to 2007. Through research on these sites, we built a database, including information relating to the work sought from specific descriptors for studies in the area of victimization of children and adolescents, with reference to a list provided by Faleiros (2000). After reading the summary of the work, the number of recovered 25 productions was reached - including theses, dissertations and articles. For analysis of the material used in the analysis of thematic content. Two axes themes were established in order to guide the analysis: conceptual elements of commercial sexual exploitation, and theoretical and methodological strategies employed. The axes have as reference for analysis a chapter built on the concept of commercial sexual exploitation, so that all analysis is anchored on it. The analysis points to the existence, still strong, conceptual and terminological confusion about ESCCA. Few studies have not demonstrated this confusion, maintaining a consistent theoretical approach. In relation to the theoretical and methodological strategies, there is a great diversity of approaches in psychology surrounding the phenomenon of ESCCA, enriching levels of understanding and action. This diversity reflects a constitutive heterogeneity of psychological science. We emphasize the perspective of socio-historical psychology, most frequently among the publications. It is hoped that this research will help advance the qualitative approach to ESCCA, especially in the field of psychology, as well as contribute to new research in the area and construction of new means of addressing this human rights violation

Adolescentes preocupadas em conquistar um corpo magro: Um estudo sobre discursos produzidos em diários eletrônicos

The concern about a good physical condition is heavily present nowadays, in documentary films about health and in the media, and it is also expressed through the outstanding growth of physical academies, beauty institutes and aesthetic medicine and all kind of aesthetic surgeries. In the western world the body wave is a significant trend, characterized by the great investments in body image. However, what is overlooked is the fact that in parallel trend grows the number of teenagers, especially females, with all kind of problems related to their body image. As adolescence is a moment of transformations, teenagers tend to be more aware of their body image and often neglect food ingestion and try to build their bodies following the images they have from top models and movie stars. The low self-esteem accompanying this sort of experience is an additional problem. Therefore the research aim to analyze discourses regarding the body image produced in world wide web diaries (blogs). The blogs selection was made through the site www.blogs.com.br, which is considered the widest guide of electronic diaries in Brazil. We looked after blogs including the keyword body and from adolescents aged 10 to 19, who showed concern about a slim body. Three blogs were chosen, considering the example criteria. Discourse analysis shows that these teenagers feel unsatisfied with their bodies, searching by all means the thinness presented as a aesthetic paradigm in western societies which often implies neglecting their own health, using appetite inhibitor drugs, restricting or totally abstaining food ingestion for long periods of time, or provoking themselves vomits after ingesting food. These behaviors, together with intense fear of gaining weight, can be characterized as alimentary disorders, related to the body image. As they usually hide this sort of behaviors from family and friends who do not share this concern, the blogs seem to be an easy tool for adolescents to find peers with whom to share common values and ideas and reaffirm their identities and virtual sense of community

Falhas e complicações com o uso de prótese parcial removível inferior de extremidade livre bilateral

Aim: To determine the frequency and type of complications related to removable partial denture (RPD) less, Kennedy Class I, over time . Materials and Methods: This observational study consisted of a sample of 65 users PPR lower arches in Kennedy Class I and dentures, rehabilitated in the Department of Dentistry, Federal University of Rio Grande do Norte (UFRN). Patients were followed through periodic controls during periods of 60 days, 6 months and 1 year from installation. After the first year of control had other returns annually. The occurrence of complications or prosthetic failure was observed and recorded in a specific clinical record over 39 months. The patterns of failures observed were classified in the following situations: occurrence of traumatic ulcers after 2 months of installation, lack of retention, fracture or caries in the rest, fracture or dislocation of the artificial teeth, the larger connector fracture, fracture clip fracture support, poor support (need to reline the denture) and prosthesis fracture. Results: The incidence of complications was low frequency, being higher in the second year of use of the prosthesis. Among the complications that occurred more is the loss of retention (31.57%). Failures more severe and difficult to solve as the fracture elements of the metal structure of the PPR had low occurrence and were represented by only one case of the larger connector (5.3%) fractures. Conclusion: Removable partial dentures mandibular free end opposing of the conventional dentures have a low complication rate after 39 months of use when subjected to periodic controls

Fatores que influenciam o apoio dos residentes á megaeventos: uma análise sobre o projeto FIFA WORLD CUP 2014 em Natal/RN

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Avaliação do ciclo de vida no Brasil: uma investigação nas principais bases científicas nacionais

A avaliação do ciclo de vida (ACV) é uma metodologia de avaliação de impacto ambiental de produtos e sistemas de produção considerando todo o ciclo de vida, desde a aquisição de matérias-primas até a disposição final. Este trabalho consistiu na investigação do progresso dos estudos sobre ACV no Brasil, por meio de uma pesquisa bibliográfica em eventos e periódicos oficiais ou reconhecidos pela Associação Brasileira de Engenharia de Produção e na base de dados SciELO Brasil. Foram identificados 80 artigos, a maioria de instituições das regiões Sul e Sudeste. A Universidade de São Paulo (USP) e Universidade Federal de Santa Catarina (UFSC) apresentaram o maior número de publicações dentre as 50 instituições identificadas. Verificou-se que 17 artigos aplicaram efetivamente a metodologia ACV em um estudo de caso, sendo que 11 utilizaram a metodologia para avaliar processo produtivo e 6 para comparar materiais ou processos