Using compact structure to improve the defect of traditional transmission line filter which size is too big or transmission line is too long. Two special structures are used to implement the filter that is smaller or superior characteristic. One of the two structures is called DGS that etched defect in the ground plane. The etched lattice shape for the transmission line consists of narrow and wide etched areas in backside metallic ground, which give rise to increasing the effective capacitance and inductance of a transmission line, respectively. Thus, by using this character, the low-pass filters are designed and implemented easily. Another structure is coupled of microstrip square open-loop resonators. First, the coupling coefficients of the three basic coupling structures versus distance between adjacent resonators and different offset is established by means of three-dimensional field analysis methods. Then, the band-pass filter will be implemented by the combination of three basic coupling structures. Finally, two low-pass filter which have cutoff frequency 5.4GHz¡B2.26GHz and a four-pole band-pass filter are designed and fabricated. All theoretical and experimental performance is presented.

En la presente tesis de investigación se busca encontrar las variaciones de parámetros como periodos, distorsiones y fuerzas internas al cambiar el número de pisos y condiciones geotécnicas cuando se realiza un análisis sísmico tradicional considerando empotrada la base y cuando se incorpora la interacción suelo–estructura por medio del modelo dinámico D.D. Barkan – O.A. Savinov en edificaciones comunes (hoteles). Para la obtención de los resultados de los parámetros se realizan análisis sísmicos de todos los modelos en el software SAP 2000. Asimismo, esta investigación se ha realizado porque en la actualidad no existen datos sobre en qué casos, según tipo de suelo y tamaño de edificación es representativo incluir la interacción suelo-estructura al realizar el análisis sísmico. Los modelos estructurales por utilizar son de 3, 5, 7 y 9 pisos en las condiciones geotécnicas S1 (suelos muy rígidos), S2 (suelos intermedios) y S3 (suelos blandos). Asimismo, el sistema estructural es una estructura aporticada sobre zapatas aisladas. Principalmente, se han encontrado que al incluir la interacción suelo – estructura en el análisis sísmico y a medida que la condición geotécnica se haga más desfavorable las variaciones de las distorsiones por cada modelo (3, 5, 7 y 9) aumentan. Adicionalmente, las variaciones de los periodos por cada tipo de suelo (S1, S2 y S3) disminuyen cuando se incrementa el número de pisos. Es decir, que la variación es mayor cuando son estructuras bajas. / This research thesis seeks to find the variations of parameters such as periods, distortions and internal forces by changing the number of floors and geotechnical conditions when a traditional seismic analysis is performed considering the base embedded and when the soil-structure interaction is incorporated by middle of the dynamic DD model Barkan - O.A. Savinov in common buildings (hotels). To obtain the results of the parameters, seismic analyzes of all the models are performed in the SAP 2000 software. Likewise, this research has been carried out because there are currently no data on in which cases, depending on the type of soil and size of the building, it is representative to include the soil-structure interaction when performing the seismic analysis. The structural models to be used are 3, 5, 7 and 9 floors in geotechnical conditions S1 (very rigid soils), S2 (intermediate soils) and S3 (soft soils). Likewise, the structural system is a structure contributed on isolated footings. Mainly, it has been found that by including the soil - structure interaction in the seismic analysis and as the geotechnical condition becomes more unfavorable, the variations of the distortions for each model (3, 5, 7 and 9) increase. Additionally, the variations of the periods for each type of soil (S1, S2 and S3) decrease when the number of floors increases. That is, the variation is greater when they are low structures. / Tesis

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-10-17T18:47:03Z No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-10-18T16:18:59Z (GMT) No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-18T16:18:59Z (GMT). No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-01-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Topology optimization provides design solutions to several engineering applications and density methods are the most popular approach in this field. However, when it comes to building design, the dimension of the extended domain related to the high of the building provides material concentration at the basis of the building. On the other side, the ground structure method provides desirable grid solutions using a highly connected truss in an approach close to size optimization techniques. This work presents a prospective study about the application of ground structure method to obtain bracing systems for buildings comparing with the known solutions obtained by density methods. Desirable manufacturing constraints such as patterns repetition and symmetry are considered. Multiple loading functions are Simulations are developed in two-dimensional building configurations to validate the method and show the structural comportment. Three dimensional examples are developed to show possibility of interesting solutions obtained with the ground structure method. / A otimização de topologia fornece soluções para muitas aplicações da engenharia e os métodos baseados na densidade são as abordagens mais populares neste campo. No entanto, quando se trata da concepção de edifícios a dimensão do domínio estendido em relação à altura dos edifícios propicia a concentração de matéria na base do edifício. Por outro lado, o método da ground structure fornece soluções desejáveis usando uma treliça altamente conectada em uma abordagem próxima as técnicas de otimização de dimensões. Este trabalho apresenta um estudo sobrea a aplicação do método da ground structure para obtenção do projeto conceitual dos sistemas de contraventamento dos edifícios comparando com o conhecido método baseado na densidade. Para isso leva-se em consideração características de manufatura como simetria e repetição de padrão, além das considerações de múltiplos carregamentos. Simulações em 2D são apresentadas para validação do método e observação do comportamento estrutural. Exemplos em 3D com arquiteturas mais ousadas são desenvolvidos para mostrar as possiblidades arquitetônicas que as soluções obtidas pela ground structure propicia.

A compliant mechanism gains its motion from the deflection of flexible members or the deformation of one portion of materials with respect to other portions. Design and operation of compliant mechanisms are very important, as most of the natural objects are made of compliant materials mixed with rigid materials, such as the bird wings. The most serious problem with compliant mechanisms is their fatigue problem due to repeating deformation of materials in compliant mechanisms. This thesis presents a study on the computational framework for designing a compliant mechanism under fatigue strength control. The framework is based on the topology optimization technique especially ground structure approach (GSA) together with the Genetic Algorithm (GA) technique. The study presented in this thesis has led to the following conclusions: (1) It is feasible to incorporate fatigue strength control especially the stress-life method in the computational framework based on the GSA for designing compliant mechanisms and (2) The computer program can well implement the computational framework along with the general optimization model and the GA to solve the model. There are two main contributions resulting from this thesis: First one is provision of a computational model to design compliant mechanisms under fatigue strength control. This model also results in a minimum number of elements of the compliant mechanism in design, which means the least weight of mechanisms and least amount of materials. Second one is an experiment for the feasibility of implementing the model in the MATLAB environment which is widely used for engineering computation, which implies a wide applicability of the design system developed in this thesis.

The objective of this paper is to present an efficient miniaturized antenna design and simulation of a highly isolated multi-port micro-strip antenna for multiple-input multiple-output communication (MIMO) systems. Three geometric configurations were proposed and compared to achieve an isolation of as low as –30 dB without affecting the antenna performance greatly. The antenna was designed to operate at a resonance frequency of 2.45 GHz (fc ). Ferrite material beneath each meander structure was used for miniaturization purposes as well as an FR4 substrate with a compact overall area of .75 lambda0 ×.5 lambda0 for a system board, where lambda0 is the free space wavelength. A ground plane with small etched slits was used for isolation purposes. A maximum gain of 4.6 dBi in the azimuthal plane was achieved. Index Terms: MIMO, meander antenna, four-port antenna, defected ground structure / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

Submitted by Alex Sandro R?go (alex@ifpb.edu.br) on 2016-09-01T13:11:30Z No. of bitstreams: 1 An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) / Approved for entry into archive by Alex Sandro R?go (alex@ifpb.edu.br) on 2016-09-01T13:12:05Z (GMT) No. of bitstreams: 1 An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) / Made available in DSpace on 2016-09-01T13:12:05Z (GMT). No. of bitstreams: 1 An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) Previous issue date: 2015 / Esta Disserta??o descreve a aplica??o do m?todo das Diferen?as Finitas no Dom?nio do Tempo (FDTD ? Finite Difference Time Domain) para a an?lise de filtros fabricados em linhas de microfita para a faixa de micro-ondas. O m?todo FDTD 3-D, desenvolvido em linguagem C, implementa condi??es de contorno com o uso da t?cnica PML (Perfect Matched Layer), permitindo a determina??o num?rica dos campos eletromagn?ticos com uma menor interfer?ncia das reflex?es indesej?veis nos limites da malha FDTD. A fim de comparar os resultados obtidos com o m?todo FDTD, o software comercial Ansoft DesignerTM tamb?m ? usado para simula??o dos filtros abordados. Cinco prot?tipos foram constru?dos e caracterizados experimentalmente com o uso de um analisador de redes vetorial, Agilent N5230A. Estes resultados num?ricos e experimentais s?o usados para a compara??o do m?todo FDTD 3-D desenvolvido. O m?todo FDTD foi aplicado para an?lise de um filtro passa-baixa em linha de microfita, de filtros DGS (Defected Ground Structure) unit?rios e peri?dicos e de um filtro spur-line. Os resultados de simula??o foram concordantes com os experimentos realizados com um erro m?ximo de 4,8% para os filtros abordados. Atrav?s de varia??es na malha FDTD, uma an?lise de desempenho do m?todo FDTD foi realizada em termos de precis?o e esfor?o computacional.

Submitted by Alex Sandro R?go (alex@ifpb.edu.br) on 2016-11-25T13:25:10Z No. of bitstreams: 1 9- Laio Lucas de Souza - An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) / Approved for entry into archive by Alex Sandro R?go (alex@ifpb.edu.br) on 2016-11-25T13:25:58Z (GMT) No. of bitstreams: 1 9- Laio Lucas de Souza - An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) / Made available in DSpace on 2016-11-25T13:25:58Z (GMT). No. of bitstreams: 1 9- Laio Lucas de Souza - An?lise e Simula??o de Filtros de Microfita Utilizando o M?todo FDTD.pdf: 3682016 bytes, checksum: e7b92fd51edaba9be1f80daf86f10b4d (MD5) Previous issue date: 2016-11-25 / Esta Disserta??o descreve a aplica??o do m?todo das Diferen?as Finitas no Dom?nio do Tempo (FDTD ? Finite Difference Time Domain) para a an?lise de filtros fabricados em linhas de microfita para a faixa de micro-ondas. O m?todo FDTD 3-D, desenvolvido em linguagem C, implementa condi??es de contorno com o uso da t?cnica PML (Perfect Matched Layer), permitindo a determina??o num?rica dos campos eletromagn?ticos com uma menor interfer?ncia das reflex?es indesej?veis nos limites da malha FDTD. A fim de comparar os resultados obtidos com o m?todo FDTD, o software comercial Ansoft DesignerTM tamb?m ? usado para simula??o dos filtros abordados. Cinco prot?tipos foram constru?dos e caracterizados experimentalmente com o uso de um analisador de redes vetorial, Agilent N5230A. Estes resultados num?ricos e experimentais s?o usados para a compara??o do m?todo FDTD 3-D desenvolvido. O m?todo FDTD foi aplicado para an?lise de um filtro passa-baixa em linha de microfita, de filtros DGS (Defected Ground Structure) unit?rios e peri?dicos e de um filtro spur-line. Os resultados de simula??o foram concordantes com os experimentos realizados com um erro m?ximo de 4,8% para os filtros abordados. Atrav?s de varia??es na malha FDTD, uma an?lise de desempenho do m?todo FDTD foi realizada em termos de precis?o e esfor?o computacional.

[pt] Métodos de otimização topológica estrutural visam obter a melhor distribuição de material dentro de um dado domínio, sujeito a carga, condições de contorno e restrições de projeto, de forma a minimizar alguma medida especificada. A otimização topológica estrutural pode ser dividida em dois tipos: contínua e discreta, sendo a forma discreta o foco da pesquisa desta dissertação. O objetivo deste trabalho é a criação de um sistema para realizar todos os passos dessa otimização, visando a resolução de problemas com grandes dimensões. Para realizar esse tipo de otimização, é necessária a criação de uma malha densa de barras, esta definida como conjunto de nós cobrindo todo o domínio, conectados através de barras, além da especificação dos apoios e das forças aplicadas. Este trabalho propõe um novo método para geração da malha densa de barras, utilizando como entrada somente o contorno do domínio que se deseja otimizar, contrapondo com métodos que necessitam de um domínio já discretizado, como uma malha de poliedros. Com a malha gerada, este trabalho implementou a otimização topológica, sendo necessário resolver um problema de programação linear. Toda a parte de otimização foi realizada dentro do framework TopSim, tendo implementado o método dos pontos interiores para a resolução da programação linear. Os resultados apresentados possuem boa qualidade, tanto na geração quanto na otimização, para casos 2D e 3D, tratando casos com mais de 68 milhões de barras. / [en] Structural topology optimization methods are used to find the optimal material distribution within a given domain, subject to loading, boundary conditions and design constraints, in order to minimize some specified measure. Structural topology optimization can be divided into two types: continuum and discrete, with the discrete type being the research focus of this dissertation. The goal of this work is the creation of a system to achieve all the steps of this optimization process, aiming problems with large dimensions. In order to perform the optimization, it is necessary create a ground structure, defined as a set of nodes covering the entire domain, connected by bars, with the supports and the applied loads. This work proposes a new method for the ground structure generation, using as input only the domain boundary, in contrast with methods that require a domain already discretized, such as a polyhedron mesh. With the generated mesh, this work has implemented the topological optimization, needing to solve a linear programming problem. All the optimization part was performed within the TopSim framework, implementing the interior point method for the linear programming resolution. The results presented have good quality, both in generation and optimization, for 2D and 3D cases, considering cases with more than 68 million bars.

The diploma thesis is focused on the design of planar filters combining fractal layouts and defected ground substrates. The diploma thesis can be divided into three main parts. First, basic knowledge about fractals is presented (creation of Minkowski Island and Koch loop, e.g.). Then, the principle of defected ground structure is described, and a combination of fractal motives with a defected ground structure is briefly introduced. Properties of investigated structures are verified by CST Microwave Studio and Ansoft HFSS. Second, different defected ground structures under the 50 transmission line are designed, and conventional equivalent filters are created. Filters are simulated and compared. In final, the investigated filters are recalculated for the substrate Arlon 25N, simulated, manufactured, measured and confronted with a conventional filter on the defected ground substrate.

This thesis reports the analysis of the rectangular shaped defected ground structure (RS-DGS) and the application of the structure on some microwave devices. DGS is analyzed in terms of its superior properties, which enables the designers to easily realize many kind of microwave devices which are impossible to achieve with the standard applications. Within the scope of this thesis, the focus is on the rectangular shaped DGS and its characteristic properties. The basic slow wave and high impedance characteristics are utilized in the design of some microwave devices. The design is carried on at the two different frequency bands: X-band and Ka band, centering at 10 GHz and 35 GHz, respectively. Finally, using the high impedance property and the coupling between the defects, a wide band 1 : 4 beam forming network is designed and implemented at 10 GHz.