Análise e projeto de superfícies seletivas de frequência com elementos pré-fractais para aplicações em comunicações indoor

In this thesis, a frequency selective surface (FSS) consists of a two-dimensional periodic structure mounted on a dielectric substrate, which is capable of selecting signals in one or more frequency bands of interest. In search of better performance, more compact dimensions, low cost manufacturing, among other characteristics, these periodic structures have been continually optimized over time. Due to its spectral characteristics, which are similar to band-stop or band-pass filters, the FSSs have been studied and used in several applications for more than four decades. The design of an FSS with a periodic structure composed by pre-fractal elements facilitates the tuning of these spatial filters and the adjustment of its electromagnetic parameters, enabling a compact design which generally has a stable frequency response and superior performance relative to its euclidean counterpart. The unique properties of geometric fractals have shown to be useful, mainly in the production of antennas and frequency selective surfaces, enabling innovative solutions and commercial applications in microwave range. In recent applications, the FSSs modify the indoor propagation environments (emerging concept called wireless building ). In this context, the use of pre-fractal elements has also shown promising results, allowing a more effective filtering of more than one frequency band with a single-layer structure. This thesis approaches the design of FSSs using pre-fractal elements based on Vicsek, Peano and teragons geometries, which act as band-stop spatial filters. The transmission properties of the periodic surfaces are analyzed to design compact and efficient devices with stable frequency responses, applicable to microwave frequency range and suitable for use in indoor communications. The results are discussed in terms of the electromagnetic effect resulting from the variation of parameters such as: fractal iteration number (or fractal level), scale factor, fractal dimension and periodicity of FSS, according the pre-fractal element applied on the surface. The analysis of the fractal dimension s influence on the resonant properties of a FSS is a new contribution in relation to researches about microwave devices that use fractal geometry. Due to its own characteristics and the geometric shape of the Peano pre-fractal elements, the reconfiguration possibility of these structures is also investigated and discussed. This thesis also approaches, the construction of efficient selective filters with new configurations of teragons pre-fractal patches, proposed to control the WLAN coverage in indoor environments by rejecting the signals in the bands of 2.4~2.5 GHz (IEEE 802.11 b) and 5.0~6.0 GHz (IEEE 802.11a). The FSSs are initially analyzed through simulations performed by commercial software s: Ansoft DesignerTM and HFSSTM. The fractal design methodology is validated by experimental characterization of the built prototypes, using alternatively, different measurement setups, with commercial horn antennas and microstrip monopoles fabricated for low cost measurements

Modelagem aplicada à análise de desempenho do provedor de serviços de uma rede de automação hospitalar ieee 802.3/pm-ah de tempo real

The incorporate of industrial automation in the medical are requires mechanisms to safety and efficient establishment of communication between biomedical devices. One solution to this problem is the MP-HA (Multicycles Protocol to Hospital Automation) that down a segmented network by beds coordinated by an element called Service Provider. The goal of this work is to model this Service Provider and to do performance analysis of the activities executed by in establishment and maintenance of hospital networks

Análise teórico-experimental do coeficiente de perfomance (COP) de um sistema de refrigeração por jato-compressão

The use of waste heat of energy conversion equipment to produce a cooling effect, consists currently in a very interesting way of efficiency improvement of energy systems. The present research has as intention the theoretical and experimental study of a new intermittent refrigeration system ejector cycle characteristics, with use of waste heat. Initially, was doing a bibliographical survey about the vapor ejector refrigeration system technology. In the following stage was doing a simulation of the corresponding thermodynamic cycle, with preliminarily intention to evaluate the performance of the system for different refrigerants fluids. On the basis of the results of the simulation were selected the refrigerant fluid and developed an experimental group of benches of the refrigeration system considered, where pressure and temperature sensory had been inserted in strategical points of the refrigeration archetype and connected to a computerized data acquisition system for measure the refrigerant fluid properties in the thermodynamic cycle. The test results obtained show good agreement with the literature

Análise das emissões atmosféricas por veículos automotores em Natal-RN

The fast urban occupation of Brazil, mainly from the last decade of 50, a sensible degradation of the quality of the air generated mainly for the activities was verified human beings associates to industrialization. From the past years, the situation has gotten worst in function of the increment of the fleet of vehicles in circulation in the great cities. Being these, in the city of Natal-RN, the ones that offer the biggest contributions to the atmospheric pollution. For atmospheric air to be a finite natural resources, indispensable and essential to the maintenance of the life in the land, is necessary to the implementation of action to improve its quality and to protect the health of the population. With the objective to study relative aspects to the characteristics of vehicles in use, the present study it searchs to analyze the levels of emissions of gases generated for vehicles converted bi-fuels into the modalities: natural gas (GNV), gasoline and alcohol, inspected for ends of register and together licensing to the State Department of Transit. One used the data gotten from inspections carried through for the company System Specialized in Inspection To propagate, in the city of the Natal-RN, capital of the State of Rio Grande do Norte, between 14 of November of 2003 and 30 of December of 2004. The analyzed parameters are established in the resolution nº 07/93 CONAMA. Of a total of 1.517 inspected vehicles, a average of 15,2% of failed was gotten, or either, that they emit levels of pollution above of the limits established for the legislation, below of the national average that is of 20,0%. The analysis of the data discloses that 7.3% of the fleet are converted the GNV; the growth of vehicles converted the GNV into the city is gradual, with a average of increment in last the 4 years of 23,3%; it has a vehicle predominance that has as combustible original to the gasoline (88,2%); the inspected fleet has average age of 8 years of use, considered young for the Brazilian standards, except for the moved one to the alcohol (average of use of 15 years). Moreover, the type of fuel is not the main parameter to define the indices of emissions; the age of the fleet is the parameter most important when emission is analyzed to propagate; the gas that more generates failed in the inspections is the corrected carbon monoxide; the vehicles generate higher indices of emissions in idling for all the fuels; the presence of the catalyser was not reflected, as it expected, in the reduction of emissions of gases toxic, however when analyzed according to year of manufacture, it was observed that for the vehicles manufactured between 1997 and 2004, reduction of 46,0% in the failed of the vehicles equipped with catalyser was gotten. In conclusion, the fleet of the studied sample, in average terms, takes care of to the requirements of Resolution CONAMA nº 07/93. The results gotten for the present study can subsidize action of public administrations that aim at to the improvement and the maintenance of the quality of air in the city of Natal-RN, as, for example, to implant a net of monitoramento of the quality of air

A argumentação como elemento discursivo na mídia digital: um estudo sobre o blog fatos e dados

This thesis studies the use of argumentation as a discursive element in digital media, particularly blogs. We analyzed the Blog "Fatos e Dados" [Facts and Data], created by Petrobras in the context of allegations of corruption that culminated in the installation of a Parliamentary Commission of Inquiry to investigate the company within the Congress. We intend to understand the influence that the discursive elements triggered by argumentation exercise in blogs and about themes scheduling. To this end, we work with notions of argumentation in dialogue with questions of language and discourse from the work of Charaudeau (2006), Citelli (2007), Perelman & Olbrechts-Tyteca (2005), Foucault (2007, 2008a), Bakhtin (2006) and Breton (2003). We also observe our subject from the perspective of social representations, where we seek to clarify concepts such as public image and the use of representations as argumentative elements, considering the work of Moscovici (2007). We also consider reflections about hypertext and the context of cyberculture, with authors such as Levy (1993, 1999, 2003), Castells (2003) and Chartier (1999 and 2002), and issues of discourse analysis, especially in Orlandi (1988, 1989, 1996 and 2001), as well as Foucault (2008b). We analyzed 118 posts published in the first 30 days of existence of the blog "Fatos e Dados" (between 2 June and 1 July 2009), and analyzed in detail the top ten. A corporate blog aims to defend the points of view and public image of the organization, and, therefore, uses elements of social representations to build their arguments. It goes beyond the blog, as the main news criteria, including the posts we reviewed, the credibility of Petrobras as the source of information. In the posts analyzed, the news values of innovation and relevance also arise. The controversy between the Blog and the press resulted from an inadequacy and lack of preparation of media to deal with a corporate blog that was able to explore the characteristics of liberation of the emission pole in cyberculture. The Blog is a discursive manifestation in a concrete historical situation, whose understanding and attribution of meaning takes place from the social relations between subjects that, most of the time, place themselves in discursive and ideological dispute between each other - this dispute also affects the movements of reading and reading production. We conclude that intersubjective relationships that occur in blogs change, in the form of argumentative techniques used, the notions of news criteria, interfering with scheduling of news and organization of information in digital media outlets. It is also clear the influence that the discursive elements triggered by argumentation exercise in digital media, trying to resize and reframe frames of reality conveyed by it in relation to the subject-readers. Blogs have become part of the scenario information with the emergence of the Internet and are able to interfere in a more effective way to organize the scheduling of media from the conscious utilization of argumentative elements in their posts

Simetria de invariância de escala discreta, log-periodicidade e singularidades em tempo finito

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Análise em conjunta de testes cosmológicos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Análise química de produtos de incrustação em dutos de petróleo por espectometria de fluorescência de raios X

The quantitative chemical characterization of the inorganic fraction of scale products is very relevant in studying, monitoring and controlling corrosive processes of oil pipelines. The X-ray fluorescence spectrometry (XRF) is a very versatile analytical technique, which can be used in quantitative analysis in solid samples at low concentrations of the chemical element, in the order of few ppm. A methodology that involves sample preparation diluted in the proportion of 1:7 (one portion of the sample for seven of wax), pressed as pellets was used in the XRF calibration for chemical analysis of scale products from oil pipelines. The calibration involved the preparation of reference samples from mixtures of P.A. reagents, aiming to optimize the time consumed in the steps of sample preparation and analysis of Al, Ba, Ca, Fe, K, Mg, Mn, Na, P, S, Si, Sr and Ti, using the same pressed pellet for trace and major elements analysis

Violência contra a mulher:uma análise do trabalho do Centro de Referência da Assistência Social-CREAS/Parnamirim-RN.

This work demonstrates the results obtained from research on violence against women: an analysis of the work from reference center of the Social Assistance-CREAS, held in the city of Parnamirim/RN from September 2008 extending through the february of 2009. Having as goal to investigate and examine in a longitudinal cut, which specifically covers the period from 2006 to 2007, find out extent the actions taken by the Reference Center Specialized Social Assistance- CREAS, contributed to the change of women who were there, by checking if there was any change in their positions ahead of the violence and if they began to realize how social subjects, able to control their living conditions and interfere in the orientation of social dynamics Have a particular emphasis on the presence of work and schooling or lack of them is also a factor to be allied to the barriers and rules imposed on women in contemporary society. In this study it was found through a qualitative research guided by dialectical and implemented through the use of documentary research, observation, semi-structured interview and an extensive theoretical background on the subject in question that the woman victim of violence is in a complex and contradictory context where there is both the construction and deconstruction of rights, a view that there are strong influences of patriarchal culture and the consequences of social issues that specifically searched for the public, focuses on social, economic , political, social and cultural. In this sense, the National Policy to Combat Violence against Women, operated by CREASE Parnamirim, is also reflected in its early stages in the life of these women are to nurture a real chance for these victims of violence, to perceive themselves as social subjects can control their lives and interfere in their own destinies. We want this study to add more knowledge to help and most appropriate intervention in this reality, but without the intention of reaching exhaustion, but to subsidize future studies on the topic of women victims of violence

Violência contra a mulher: uma análise do trabalho do centro de referência da assistência social-CREAS/Parnamirim

This work demonstrates the results obtained from research on violence against women: an analysis of the work from reference center of the Social Assistance-CREAS, held in the city of Parnamirim/RN from September 2008 extending through the february of 2009. Having as goal to investigate and examine in a longitudinal cut, which specifically covers the period from 2006 to 2007, find out extent the actions taken by the Reference Center Specialized Social Assistance-CREAS, contributed to the change of women who were there, by checking if there was any change in their positions ahead of the violence and if they began to realize how social subjects, able to control their living conditions and interfere in the orientation of social dynamics Have a particular emphasis on the presence of work and schooling or lack of them is also a factor to be allied to the barriers and rules imposed on women in contemporary society. In this study it was found through a qualitative research guided by dialectical and implemented through the use of documentary research, observation, semi-structured interview and an extensive theoretical background on the subject in question that the woman victim of violence is in a complex and contradictory context where there is both the construction and deconstruction of rights, a view that there are strong influences of patriarchal culture and the consequences of social issues that specifically searched for the public, focuses on social, economic , political, social and cultural. In this sense, the National Policy to Combat Violence against Women, operated by CREASE Parnamirim, is also reflected in its early stages in the life of these women are to nurture a real chance for these victims of violence, to perceive themselves as social subjects can control their lives and interfere in their own destinies. We want this study to add more knowledge to help and most appropriate intervention in this reality, but without the intention of reaching exhaustion, but to subsidize future studies on the topic of women victims of violence

Serviço social na educação: análise das tendencias dos perfis pedagógicos do assistente social

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

O planejamento turístico e o comércio ambulante : uma análise à luz da teoria das representações sociais

The Social Representation Theory provides subsidies to scientifically analyze what is called common sense, suggesting that thought be given credibility to the individual, from the assignment of logic to it. The Representations allow us to interpret, understand, explain and thus classify information, events and people. In this sense, this study aimed to analyze how social representations of the actors of the intinerant traders who operate in Ponta Negra/RN can be used as an element for tourism planning. To achieve the desired goals, we conducted a qualitative study, from a descriptive study, using methods of data collection the research literature, the technique of free association of words and the questionnaire, applied with 90 intinerant traders who work in Ponta Negra/RN beach. As tools of data analysis were used to analyze literature, and software EVOC and SPHINX. This research has revealed the predominance of people in itinerant male, between 18 and 28 years, with incomplete primary education, no contributors of Previdência Social and working seven days a week. The core elements of representations brings that explain that their knowledge is guided by collectively shared knowledge in the culture of tourism, which is seen as something that brings economics benefits (money) to the society, from the travel and entertainment. The plan represents the forward thinking, based on development plans that seek improvements and organization. The structure and operation of tourism planning in Natal/RN, there were no representation of intinerant traders. It is concluded that understanding the needs of itinerant traders provides grants to developing strategies for the development of tourism. This is achieved from its inclusion in tourism planning, since it enables tourism managers to understand how they are capturing, interpreting and acting on their next reality, since these representations are fundamental in forming opinions and the establishment of individual attitudes and collective. Thus, it is an important theory to be used to subsidize social research with individuals living reality and local needs, but which is the margin of decision-making processes of economic in the Brazil

Análise espectroscópica da estrela HD 150050: uma nova estrela gigante rica em lítio

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Análise do Efeito Goos-Hanchen e Não-reciprocidade do fluxo de potência em antiferromagnéticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Análise de tensões integrada a sistema de engenharia reversa para projeto e confecção de próteses

This work consists of the conception, developing and implementation of a Computational Routine CAE which has algorithms suitable for the tension and deformation analysis. The system was integrated to an academic software named as OrtoCAD. The expansion algorithms for the interface CAE genereated by this work were developed in FORTRAN with the objective of increase the applications of two former works of PPGEM-UFRN: project and fabrication of a Electromechanincal reader and Software OrtoCAD. The software OrtoCAD is an interface that, orinally, includes the visualization of prothetic cartridges from the data obtained from a electromechanical reader (LEM). The LEM is basically a tridimensional scanner based on reverse engineering. First, the geometry of a residual limb (i.e., the remaining part of an amputee leg wherein the prothesis is fixed) is obtained from the data generated by LEM by the use of Reverse Engineering concepts. The proposed core FEA uses the Shell's Theory where a 2D surface is generated from a 3D piece form OrtoCAD. The shell's analysis program uses the well-known Finite Elements Method to describe the geometry and the behavior of the material. The program is based square-based Lagragean elements of nine nodes and displacement field of higher order to a better description of the tension field in the thickness. As a result, the new FEA routine provide excellent advantages by providing new features to OrtoCAD: independency of high cost commercial softwares; new routines were added to the OrtoCAD library for more realistic problems by using criteria of fault engineering of composites materials; enhanced the performance of the FEA analysis by using a specific grid element for a higher number of nodes; and finally, it has the advantage of open-source project and offering customized intrinsic versatility and wide possibilities of editing and/or optimization that may be necessary in the future