This thesis deals with the study and development of innovative techniques for the synthesis of antennas able to fulfill the tight requirements of modern wireless communication systems. By exploiting the advantages given by the use of geometries based on spline and fractal shapes, the aim of the proposed synthesis techniques is the design of small Ultra-Wideband (UWB) and multi-band antennas. The synthesis of UWB antennas is carried out by means of two different approaches which consider the antenna characterization in the frequency and in the time domain, respectively. The antenna structure is based on a spline representation which allows the description of complex contour by means of a limited set of control parameters. Regarding the synthesis of multi-band antennas, an approach based on the perturbation of fractal geometries is proposed. The perturbation breaks the fixed relationships among resonances typical of standard fractal geometries, allowing the use of fractal antennas for practical applications. By exploiting the knowledge acquired during the synthesis of UWB spline-shaped antennas, a preliminary assessment of an approach for the design of multi-band antennas with spline-based geometries is also reported. Finally, the integration of UWB antennas in array layouts is addressed. Towards this end, first a methodology for the design of aperiodic UWB linear arrays populated by spline-shaped radiating elements is proposed. Successively, the design of an array of UWB elements for imaging applications is described. In order to assess the effectiveness as well as the reliability of the proposed antenna synthesis approaches, both numerical and experimental results are reported.

In this work, the synthesis of clustered phased array antennas characterized by an irregular organization of tiles modules is addressed. By exploiting tiling theorems drawn from the mathematical theory, optimal and sub-optimal methods for the optimization of tiles arrangements and the corresponding excitations minimizing user-defined cost functions are presented. An enumerative approach able to retrieve the optimal clustering providing the maximum aperture coverage and the best radiation performance is proposed to deal with the synthesis of low/medium-size arrays. Based on the same optimal theorems and still exploiting the algorithmic procedures at the basis of the enumerative approach, an innovative schemata-bas ed optimization method is introduced for designing large arrays, as well. A set of numerical examples and full-wave simulations, concerned with different aperture sizes, is reported to assess the effectiveness, the limitations, and the ranges of computationally-admissible applicability of the proposed methods.

In the framework of antenna array synthesis and control, this thesis focus on the development and analysis of techniques based on the Bayesian Compressive Sensing (BCS) for the design of sparse antenna arrays and for the estimation of the direction of arrival (DoA) of signals impinging on an antenna array. After formulating the sparse-array synthesis problem in a probabilistic fashion, the single-task BCS (ST-BCS) is applied to the synthesis of symmetrical antenna arrays with real weights. In order to deal with the synthesis of sparse arrays with complex weights, the multitask version of the BCS (MT-BCS) is employed to correlate the real and imaginary part of the resulting excitation distribution. Concerning the DoA estimation problem, starting from the observation that the signals impinging on the antenna array are sparse in the spatial domain, a single-snapshot ST-BCS -based technique is proposed. Moreover, the MT-BCS -based extension of this technique is introduced in order to enhance the quality of the estimations through the exploitation of the correlation among different snapshots. In the numerical validation, an exhaustive analysis has been performed to assess effectiveness, reliability, but also limitations of the proposed methodologies. Comparisons with state-of-the-art are reported and discussed, as well.

Campi Flegrei is a large volcanic complex located west of the city of Naples, Italy. The area has been the site of volcanic activity for more than 60 ka and represents a potential volcanic hazard owing to the large local population. In this study, the geochemistry of the magma associated with two different eruptions at Campi Flegrei has been characterized, with the aim to identify geochemical trends that may help to predict the style and nature of future eruptions. Two eruptions of different age and eruptive style have been selected for study, Fondo Riccio (9.5 ka) and Minopoli 1 (11.1 ka). A scoria (CF-FR-C1) and a bomb (CF-FR-C2) were collected from the Fondo Riccio eruption, and two scoria samples were collected from Minopoli 1 (CF-Mi1-C1 and C2) eruption. The pre-eruptive volatile content of magma plays an important role in the style of eruption and can be assessed from studies of melt inclusions (MI) contained in phenocrysts. Major and trace elements in Fondo Riccio MI show a wider variation compared to those in Minopoli 1 MI suggesting that the Fondo Riccio magma residence time was longer compared to the Minopoli 1 magma. Analyses of volatile contents in MI suggest that Fondo Riccio magma may have been more water-rich than Minopoli 1 magma, consistent with the more explosive character of this eruption compared to Minopoli 1. Trace element data suggest a combination of arc volcanic and upper continental crust magma as the source for the Fondo Riccio and Minopoli 1 eruptions. / Master of Science

Made available in DSpace on 2015-04-23T12:42:31Z (GMT). No. of bitstreams: 1 Dissetacao-Manuel Filho.pdf: 429783 bytes, checksum: f77156ce50ffcff6793d5544747ef1fc (MD5) Previous issue date: 2003-11-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta pesquisa teve como principal meta analisar as estruturas orgânicas de duas prefeituras de universidades que possuem seus próprios Campi . Com base na Teoria da Contingência, que fundamentou a pesquisa, variáveis do contexto foram relacionadas, definidas e operacionalizadas para funcionarem como variáveis independentes e influenciadoras das variáveis de estrutura, as quais foram aqui também determinadas, definidas e operacionalizadas. O universo da pesquisa constituiu-se de duas Prefeituras de Universidades, sendo uma Federal, a Universidade do Amazonas e outra, particular, a Universidade Luterana de Manaus que possuem seus próprios Campi‟. A técnica de coleta de dados utilizada na pesquisa principal foi a de entrevista pessoal e de levantamento empírico de dados em cada divisão funcional das prefeituras. Os dados foram tratados a analisados utilizando a técnica de estatística descritiva. As conclusões finais a que se chegou através da análise das informações coletadas estão anunciadas no Capitulo VI desta dissertação.

This dissertation informs about the life and work cremonese painter, architect and decorator Giulio Campi (c. 1502-1572), who became in 1541 the author of the decorations for the triumphal entry of Emperor Charles V in Cremona. Together with his colleague Camille Boccaccino suggested a number of triumphal arches, whose appearance has been preserved to this day on preparatory drawings. A number of preparatory drawings, which are part of the recently discovered album of the Clara - Aldringen in Teplice, keep the National Gallery in Prague. This thesis concerns the problems of Campi's proposals of the arches - addresses visual effects that might have had an influence on the Campi's drawing expression, features other Campi's surviving drawings from the collection of the European institutions and summarizes a form of the Charles V Trionfo in 1541 and Philip II. Trionfo in 1549 in Cremona.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2018-06-13T18:58:18Z No. of bitstreams: 1 texto completo.pdf: 49008443 bytes, checksum: 19e6dcf52e7a0f22d6e04436b5eb14b1 (MD5) / Made available in DSpace on 2018-06-13T18:58:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 49008443 bytes, checksum: 19e6dcf52e7a0f22d6e04436b5eb14b1 (MD5) Previous issue date: 2018-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho foi dividido em dois estudos de caso. O primeiro buscou identificar as variáveis socioeconômicas, as distâncias e os fatores comportamentais que motivam o uso do transporte cicloviário em universidades. O segundo teve como objetivo a proposição de uma metodologia para elaboração de rotas cicláveis em campi universitários. Ambos estudos tiveram como local de análise o campus Viçosa da Universidade Federal de Viçosa. A metodologia proposta para esses estudos consistiu das seguintes etapas: (i) aplicação de questionário; (ii) identificação do local de moradia da população; (iii) análise estatística descritiva e multivariada; (iv) relacionar as variáveis socioeconômicas e as distâncias do local de moradia ate' a universidade com a escolha do modo de transporte; (V) identificar as componentes principais da percepção dos usuários; (vi) reconhecimento da infraestrutura viária existente na área de estudo; (Vii) análise das regulamentações de infraestruturas cicloviárias vigentes no Brasil; (viii) realização de contagens classificatórias direcionadas de veículos; (ix) tratamento de dados; (x) elaboração de propostas; (xi) análise de viabilidade técnica das propostas apresentadas; (xii) validação das propostas viáveis. Como resultados todas as variáveis socioeconômicas testadas e a distância demostraram-se influentes na escolha do modo de transporte. Obteve-se também quatro componentes principais com a análise fatorial, dentre elas: a segurança, o benefício, a facilidade e os fatores estruturais. Além disso, as ciclovias e ciclofaixas foram as infraestruturas cicloviárias propostas para o campus Viçosa da UFV. A metodologia proposta para a implantação de infraestruturas cicloviárias em campi universitários, bem como a identificação dos motivos que levam a comunidade acadêmica a utilizar bicicletas, podem auxiliar os planejadores de transportes a promovê-las em universidades. / This work was divided into two case studies. The first one sought to identify the socioeconomic variables, the distances and the behavioral factors that motivate the use of cycle transport in universities. The second one had the objective of proposing a methodology for the elaboration of cycling routes in university campuses. Both studies had as analysis site the Viçosa campus of the Federal University of Viçosa. The methodology proposed for these studies consisted of the following steps: (i) questionnaire application; (ii) identification of the dwelling place of the population; (iii) descriptive and multivariate statistical analysis; (iv) to relate the socioeconomic variables and the distances from the place of residence to the university with the choice of mode of transportation; (V) identify the main components of user perception; (vi) recognition of the existing road infrastructure in the study area; (vii) analysis of the bicycling infrastructure regulations in force in Brazil; (viii) conducting classificatory counts of vehicles; (ix) data processing; (x) preparation of proposals; (xi) feasibility analysis of the proposals; (xii) validation of viable proposals. As a result of all socioeconomic variables tested and distance proved to be influential in the choice of mode of transport. We also obtained four main components with factorial analysis, among them: safety, benefit, facility and structural factors. In addition, the bike lanes and bike paths were the viable bicycle infrastructure for the Viçosa campus of the UFV. The proposed methodology for the implementation of cycling infrastructure on university campuses, as well as the identification of the reasons that lead the academic community to use bicycles, can help transport planners to promote them in universities.

Phased antenna arrays provide ultimate performance in areas where high directivity and electronic scanning are needed. That performance is achieved by involving large number of radiators as well as corresponding control units. As a result, such systems become bulky and heavy. In order to reduce the number of control units, elements are grouped in subarrays with one of the control units, such as time delay, put at the subarray level. The drawback of this approach is that if elements are grouped into subarrays producing repetitive patterns in the array structure, radiation pattern of such array will be affected by undesired grating lobes. To eliminate that effect, subarrays of irregular shapes, such as polyominoes, are used. Still, those structures are an object for optimization. This work aims at applying optimization techniques like genetic algorithm to the problem of finding optimal structures of phased antenna arrays composed of polyomino-shaped subarrays. For this purpose a new mathematical model, new algorithm and optimization methods are developed. Application of those techniques showed significant advances in radiation characteristics, in particular sidelobe level. Also new features were enabled, for example, multi-beam radiation pattern forming.

No contexto da crescente problemática da água, soluções em diferentes níveis têm sido adotadas no Brasil e no mundo. Exemplo de atuação no nível dos sistemas prediais, o uso racional da água tem sido objeto de diversos estudos. Neste trabalho, são avaliados, segundo uma abordagem sistêmica, as atividades a serem contempladas na implementação de Programas Permanentes de Uso Racional da Água, especialmente em campi universitários, e seus potenciais resultados. Características dos campi como área, número de edificações, população e consumo de água elevados, além do desenvolvimento de múltiplas atividades, demonstram sua importância e justificam a atenção. São avaliadas, portanto, as atividades de planejamento, pré-implantação, implantação e pós-implantação, além das atividades de gestão da demanda de água, que devem permear todo o Programa. Como resultado desta implementação estruturada, propõe-se, como impactos - a redução do consumo de água, e como efeitos - alterações no sistema de suprimento de água fria, em rotinas administrativas e de manutenção predial, e em parâmetros de projeto; desenvolvimento tecnológico dos equipamentos; despertar para a conservação da água; e mudanças comportamentais dos usuários. A implementação e os resultados do Programa de Uso Racional da Água da Universidade de São Paulo (PURA-USP) completam o trabalho. Em desenvolvimento desde 1998, o PURA-USP obteve, como impactos até 2003, uma redução no consumo de água de 36% (de 137.881 para 88.366 m³/mês) e um benefício líquido acumulado de R$ 46,61 milhões. / In the context of the increasing water issues concerns, solutions at different levels have been adopted in Brazil and worldwide. As an example of actuation at the building systems level, water conservation has been the object of several studies. In this work, the activities to be fulfilled in the implementation of a Permanent Water Conservation Program, specially when applied to university campi, as well as the possible results are evaluated under a system approach. Campi characteristics such as area, number of buildings, population, and high water consumption, besides the development of multiple activities, show the importance of this issue and justify the concerns. The Program planning, pre-implantation, implantation and post-implantation activities, besides the water demand management activities - that must be carried out throughout the program - are evaluated then. As results of this structured implementation, it is proposed as impacts - the water consumption reduction, and as effects - the changes in the water supply systems, in administrative and building maintenance routines, in design parameters, in the technological development of fixtures, in the awakening for the alternatives water sources, and in the users behavior. The implementation and the results of the Water Conservation Program of the University of São Paulo (Programa de Uso Racional da Água da Universidade de São Paulo - PURA-USP) finish the work. The PURA-USP, in development since 1998, achieved as impacts, until 2003, 36% of water consumption reduction (from 137,881 to 88,366 m³/month) and gathered net benefit of US$ 16.13 millions (R$ 46,61 milhões).

No contexto da crescente problemática da água, soluções em diferentes níveis têm sido adotadas no Brasil e no mundo. Exemplo de atuação no nível dos sistemas prediais, o uso racional da água tem sido objeto de diversos estudos. Neste trabalho, são avaliados, segundo uma abordagem sistêmica, as atividades a serem contempladas na implementação de Programas Permanentes de Uso Racional da Água, especialmente em campi universitários, e seus potenciais resultados. Características dos campi como área, número de edificações, população e consumo de água elevados, além do desenvolvimento de múltiplas atividades, demonstram sua importância e justificam a atenção. São avaliadas, portanto, as atividades de planejamento, pré-implantação, implantação e pós-implantação, além das atividades de gestão da demanda de água, que devem permear todo o Programa. Como resultado desta implementação estruturada, propõe-se, como impactos - a redução do consumo de água, e como efeitos - alterações no sistema de suprimento de água fria, em rotinas administrativas e de manutenção predial, e em parâmetros de projeto; desenvolvimento tecnológico dos equipamentos; despertar para a conservação da água; e mudanças comportamentais dos usuários. A implementação e os resultados do Programa de Uso Racional da Água da Universidade de São Paulo (PURA-USP) completam o trabalho. Em desenvolvimento desde 1998, o PURA-USP obteve, como impactos até 2003, uma redução no consumo de água de 36% (de 137.881 para 88.366 m³/mês) e um benefício líquido acumulado de R$ 46,61 milhões. / In the context of the increasing water issues concerns, solutions at different levels have been adopted in Brazil and worldwide. As an example of actuation at the building systems level, water conservation has been the object of several studies. In this work, the activities to be fulfilled in the implementation of a Permanent Water Conservation Program, specially when applied to university campi, as well as the possible results are evaluated under a system approach. Campi characteristics such as area, number of buildings, population, and high water consumption, besides the development of multiple activities, show the importance of this issue and justify the concerns. The Program planning, pre-implantation, implantation and post-implantation activities, besides the water demand management activities - that must be carried out throughout the program - are evaluated then. As results of this structured implementation, it is proposed as impacts - the water consumption reduction, and as effects - the changes in the water supply systems, in administrative and building maintenance routines, in design parameters, in the technological development of fixtures, in the awakening for the alternatives water sources, and in the users behavior. The implementation and the results of the Water Conservation Program of the University of São Paulo (Programa de Uso Racional da Água da Universidade de São Paulo - PURA-USP) finish the work. The PURA-USP, in development since 1998, achieved as impacts, until 2003, 36% of water consumption reduction (from 137,881 to 88,366 m³/month) and gathered net benefit of US$ 16.13 millions (R$ 46,61 milhões).