In recent years, especially in the crowded city-centers where land prizes have become extremely high, tall buildings with more than 30 floors have started to be designed and constructed in Turkey. On the other hand, the technical improvements have provided the opportunity of design and construction of more slender structures which are influenced by the wind actions more. If the building is flexible, wind can interact with it so the wind induced oscillations can be significantly magnified. In order to analyze the response of such buildings under wind effects, wind tunnel tests are accepted to be the most powerful tool all over the world. In this study, a series of tests were performed in Ankara Wind Tunnel on a model building in the shape of a rectangular prism. For the similitude of flow conditions, passive devices were designed. The response of the model building was measured through a high frequency base balance which was designed specifically for this case study. Through the tests, the effects of turbulence intensity, vortex shedding and wind angle of attack on the response of the building were questioned. Finally, the results were compared with the results of various technical specifications about wind.

The development of wireless communications increases the challenges on antenna performance to improve the capability of the whole system. New fabrication technologies are emerging that not only can improve the performance of components but also provide more options for materials and geometries. One of the advanced technologies, referred to as deep X-ray lithography (XRL), can improve the performance of RF components while providing interesting opportunities for fabrication. Since this fabrication technology enables the objects of high aspect ratio (tall) structure with high accuracy, it offers RF/microwave components some unique advantages, such as higher coupling energy and compacted size. The research presented in that thesis investigates the properties of deep XRL fabricated tall microstrip transmission line and describes some important features such as characteristic impedance, attenuation, and electromagnetic field distribution. Furthermore, since most of traditional feeding structure cannot supply enough coupling energy to excite the low permittivity DRA element (εr≤10), three novel feeding schemes composed by tall microstrip line on exciting dielectric resonator antennas (DRA) with low permittivity are proposed and analyzed in this research. Both simulation and experimental measured results exhibit excellent performance. Additionally, a new simulation approach to realize Dolph-Chebyshev linear series-fed DRA arrays by using the advantages of tall microstrip line feeding structure is proposed. By using a novel T shape feeding scheme, the array exhibits wide band operation due to the low permittivity (εr=5) DRA elements and good radiation pattern due to the novel feeding structure. The tall metal transmission line feed structure and the polymer-based DRA elements could be fabricated in a common process by the deep XRL technology. This thesis firstly illustrates properties and knowledge for both DRA element and the tall transmission line. Then the three novel feeding schemes by using the tall transmission line on exciting the low permittivity DRA are proposed and one of the feeding structures, side coupling feeding, is analyzed through the simulation and experiments. Finally, the T shape feeding structure is applied into low permittivity linear DRA array design work. A novel method on designing the Dolph-Chebyshev array is proposed making the design work more efficient.

Historical conditions of colonialism, and more recently, the emergence of a post-colonial state and urbanization, have brought about rapid socio-cultural change in the Solomon Islands, characterized by heterogeneity and the influx of new cultural products. Throughout this process, notions of tradition have emerged, iterated largely through the multivocal category of kastom which is fundamentally construed in opposition to notions of Christianity and modernization. This thesis examines how these changes have affected stories, specifically a group of narratives called "kastom stories," told by students in the urban setting, and how these narratives have become a space for tradition to be stated and created. Notions of genre are explored to discover how such an amalgam of stories as that of the kastom stories regarded here could be considered as a group. I examine story structures to understand how elements from diverse sources could become integrated to the stories, and look at transformations which, in distanciating the stories from their original socio-cultural context of production, serve to recontextualize them in their present socio-cultural setting.

No description available.

The tall office building is a uniquely American invention, designed to meet the demands of industry and commerce. The technical and architectural achievements of the Chicago school of architecture marked the beginning of a new style of architecture for commercial buildings.The creative vitality that was so prevalent in Chicago was felt throughout the Midwest. Chicago style structures in a selected number of Midwestern cities are examined in the context of this thesis and these structures are promoted as historically significant to their locales and as a body of work in general. The purpose of this thesis is to document these structures and to discern the possible reasons for the dissemination of the Chicago school of architecture in the Midwest. / Department of Architecture

Earthquakes cause damages to structures and result in great human casualties and economic loss. A fraction of the kinetic energy released from earthquakes is transferred into buildings through soils. The investigation on the mechanism of the energy transferring from soils to buildings during earthquakes is critical for the design of earthquake resistant structures and for upgrading existing structures. In order to understand this phenomena well, a wave-soil-structure interaction analysis is presented. The earthquake wave-soil-structure interaction analysis of tall buildings is the main focus of this research. There are two methods available for modeling the soil-structure interaction (SSI): the direct method and substructure method. The direct method is used for modeling the soil and a tall building together. However, the substructure method is adopted to treat the unbounded soil and the tall building separately. The unbounded soil is modeled by using the Scaled Boundary Finite-Element Method (SBFEM), an infinitesimal finite-element cell method, which naturally satisfies the radiation condition for the wave propagation problem. The tall building is modeled using the standard Finite Element Method (FEM). The SBFEM results in fewer degrees of freedom of the soil than the direct method by only modeling the interface between the soil and building. The SBFEM is implemented into a 3-Dimensional Dynamic Soil-Structure Interaction Analysis program (DSSIA-3D) in this study and is used for investigating the response of tall buildings in both the time domain and frequency domain. Three different parametric studies are carried out for buildings subjected to external harmonic loadings and earthquake loadings. The peak displacement along the height of the building is obtained in the time domain analysis. The coupling between the building’s height, hysteretic damping ratio, soil dynamics and soil-structure interaction effect is investigated. Further, the coupling between the structure configuration and the asymmetrical loadings are studied. The findings suggest that the symmetrical building has a higher earthquake resistance capacity than the asymmetrical buildings. The results are compared with building codes, field measurements and other numerical methods. These numerical techniques can be applied to study other structures, such as TV towers, nuclear power plants and dams.

Thesis (M.S.)--Mississippi State University. David C. Swalm School of Chemical Engineering. / Title from title screen. Includes bibliographical references.

Thesis (M. A.)--Florida State University, 2005. / Advisor: Maxine D. Jones, Florida State University, College of Arts and Sciences, Dept. of History. Title and description from dissertation home page (viewed Jan. 27, 2006). Document formatted into pages; contains vii, 84 pages. Includes bibliographical references.

Com a crescente necessidade de projetos cada vez mais econômicos, bem como a valorização dos terrenos nos grandes centros urbanos, que leva a conseqüente necessidade de aumentar o aproveitamento destes, e com o desenvolvimento das técnicas construtivas e dos processos de análise estrutural, as edificações tornaram-se mais altas, leves, flexíveis, menos amortecidas, e, portanto, mais susceptíveis a problemas de vibrações, inclusive as induzidas pela ação do vento. Nessa situação, o amortecimento natural da edificação pode tornar-se insuficiente para reduzir os movimentos causados pela ação do vento, o que pode gerar desconforto aos usuários, quebra de vidros e até mesmo danos à estrutura. Para se atingir a redução destes deslocamentos, em alguns casos, requer-se um suplemento adicional de amortecimento, para evitar tais movimentações excessivas. Tal suplemento de amortecimento é alcançado pela instalação de um sistema de dissipação de energia na edificação. Os atenuadores dinâmicos sintonizados constituem-se em um destes sistemas de dissipação de energia, sendo utilizados para aumentar o amortecimento geral do sistema estrutural. Foram realizados testes com um modelo do edifício alto padrão “CAARC Standard Tall Building”, primeiramente sem nenhum atenuador e após com dois tipos de atenuadores com características diferentes instalados no modelo. No trabalho são apresentados e discutidos os resultados dos ensaios, realizados no Túnel de Vento Professor Joaquim Blessmann, da Universidade Federal do Rio Grande do Sul. Os atenuadores dinâmicos sintonizados (amortecedores de massa) mostraram-se eficazes na redução das vibrações transversais por desprendimento de vórtices, validando o túnel de vento como ferramenta de projeto para a prevenção e controle de fenômenos associados às vibrações induzidas pelo vento. / With the increasing need of more economic buildings, as well as the great valorization of the terrains in the center of big cities, which leads to a consequent need to improve the utilization of this terrains, and with the development of the construction techniques and of the structural analysis process, the buildings have become higher, lighter, more flexible and less damped, and, therefore, more susceptible to problems of vibrations, such as those induced by wind action. On this new situation, the natural damping of the building could become insufficient to reduce the motion caused by wind action, which can lead to discomfort to the users, break of glasses and even damage to the structure. In order to obtain a reduction on this displacements, in some cases, an additional supply of damping is needed, to avoid this excessive movements. This supply of damping is obtained by the installation of an energy dissipation system on the building. The tuned mass dampers constitute on one of this systems of energy dissipation, being used to improve the overall damping of the structural system. Tests with a model of the “CAARC Standard Tall Building” were conduced, first with no damper attached to it, and then with two different types of tuned mass dampers installed on the model in each time. The results obtained with these tests, conduced on the Túnel de Vento Professor Joaquim Blessmann, at the Universidade Federal do Rio Grande do Sul are presented and discussed. In the tests, the tuned mass dampers have shown good efficiency in the reduction of the transversal vibration caused by vortex shedding, which validates the wind tunnel as a design tool for the control and prevention of the phenomena of wind-induced vibrations.

Esta pesquisa investiga o desempenho de edifícios altos residenciais e comerciais e seu impacto no espaço urbano onde estão inseridos de acordo com a percepção dos seus usuários. São identificados os motivos relacionados à decisão de ir morar e trabalhar em edifícios altos, a preferência na escolha do pavimento utilizado e os níveis de satisfação com o desempenho das características físico espaciais de edifícios altos de acordo com o pavimento em que o usuário reside ou trabalha. Em complemento, é analisada a relação entre as características físico-espaciais de edifícios altos e os impactos causados na qualidade do contexto urbano onde se inserem. Ainda, é investigado como as características dos usuários interferem nos níveis de satisfação com o desempenho das características físico espaciais desses edifícios de acordo com o pavimento em que o respondente reside ou trabalha e na percepção dos impactos causados na qualidade do contexto urbano em que essas edificações se inserem. Como procedimento metodológico foi realizado um estudo de caso no município de Porto Alegre, RS, onde a altura máxima permitida pelo Plano Diretor é de 52 metros, equivalente a 18 pavimentos. Os métodos de coleta de dados dizem respeito aos aplicados na área Ambiente e comportamento, sistematizados por meio de levantamento de arquivos e levantamento de campo. Os dados foram coletados através de questionários aplicados via internet aos moradores de edifícios altos residenciais e pessoas que trabalham em edifícios altos comerciais. A análise de dados é realizada através de testes estatísticos não paramétricos. Os resultados desta investigação indicam que, em geral, edifícios altos residenciais e comerciais tendem a produzir ambientes que repercutem satisfatoriamente nos níveis de satisfação de seus usuários, atendendo às suas expectativas. No tocante ao desempenho de características físico-espaciais de edifícios altos relacionados à altura total dos edifícios e ao pavimento utilizado constatam-se maiores níveis de satisfação dos usuários de edifícios de 10 pavimentos do que usuários de edifícios de 18 pavimentos. Averiguou-se também que a relação do edifício alto com o contexto urbano adjacente interfere no desempenho de características físico espaciais dos edifícios e na qualidade do espaço urbano em que se inserem. Os resultados revelam ainda que as características dos usuários não interferem nos níveis de satisfação com o desempenho de edifícios altos e na percepção do impacto que geram no contexto urbano. Todavia, são identificados diferentes perfis de usuários, com diferentes necessidades em relação ao edifício onde moram ou trabalham. Por fim, espera-se que os dados desta pesquisa possam contribuir para o planejamento urbano, auxiliando na elaboração de legislações urbanísticas que regulamentam as alturas dos edifícios nas cidades, a fim de garantir um desempenho adequado dessas edificações e uma melhor qualidade urbana do contexto onde se inserem. / This research investigates the development of residential and commercial tall buildings and their impact on the urban space where they are inserted according to the perceptions of their users. Identifies the reasons for the decision to live and work in tall buildings, the preference in the choice of the floor used and the levels of satisfaction with the performance of spatial physical characteristics of tall buildings under the floor where the user resides or works. In addition, it is analyzed the relationship between physical and spatial characteristics of tall buildings and the impacts on the quality of the urban context in which they operate. Also, it is investigated how the characteristics of the users interfere in levels of satisfaction with the performance of spatial physical characteristics of these buildings according to the pavement where the respondent resides or works and perceptions of impacts on the quality of the urban context in which these buildings are inserted. As methodological procedure, a case study in the municipality of Porto Alegre, where the maximum height allowed by the Master Plan is 52 meters, equivalent to 18 floors was conducted. The methods of collecting data are part of those used in Environment and Behavior, systematized through archival records and field surveys. Data were collected through questionnaires via internet to the residents of residential tall buildings and people who work in commercial tall buildings. Data analysis is performed using nonparametric statistical tests. The results of this investigation show that, in general, commercial and residential high rise buildings tend to produce environments that impact satisfactorily on levels of user satisfaction, covering its expectations. Concerning the performance of physical and spatial characteristics of tall buildings related to the total height of buildings and pavement is used it´s realize that up higher levels of satisfaction of users of buildings of 10 floors of that users of building of 18 floors. It was found also that the relation of tall building with the adjacent urban context interferes in the performance of spatial physical characteristics of buildings and the quality of urban space in which they are located. The results also reveal that the characteristics of the users do not interfere on the levels of satisfaction with the performance of tall buildings and the perceived impact generated in the urban context. However, different profiles of users with different needs in relation to the building where they live or work are identified. Finally, it is hoped that data from this research can contribute to urban planning, assisting in the preparation of urban legislation regulating of the heights of buildings in the cities, in order to ensure adequate performance of these buildings and a better quality of urban context where they are inserted.