Microstrip circular phased array design and development using microwave antenna CAD tools

The complex design and development of a planar multilayer phased array antenna in microstrip technology can be simplified using two commercially available design tools 1) Ansoft Ensemble and 2) HP-EEsof Touchstone. In the approach presented here, Touchstone is used to design RF switches and phase shifters whose scattering parameters are incorporated in Ensemble simulations using its black box tool. Using this approach, Ensemble is able to fully analyze the performance of radiating and beamforming layers of a phased array prior to its manufacturing. This strategy is demonstrated in a design example of a 12-element linearly-polarized circular phased array operating at L band. A comparison between theoretical and experimental results of the array is demonstrated.

Design, development, and testing of X-band amplifying reflectarrays

The design and development of two X-band amplifying reflectarrays is presented. The arrays use dual-polarized aperture coupled patch antennas with FET transistors and phasing circuits to amplify a microwave signal and to radiate it in a chosen direction. Two cases are considered, one when a reflectarray converts a spherical wave due to a feed horn into a plane wave radiated into a boresight direction, and two, when the reflectarray converts a spherical wave due to a dual-polarized four-element feed array into a co-focal spherical wave. This amplified signal is received in an orthogonal port of the feed array so that the entire structure acts as a spatial power combiner. The two amplifying arrays are tested in the near-field zone for phase distribution over their apertures to achieve the required beam formation. Alternatively, their radiation patterns or gains are investigated.

Differences in physical activity between black and white girls living in rural and urban areas

This study examined the relationship of race and rural/urban setting to physical, behavioral, psychosocial, and environmental factors associated with physical activity. Subjects included 1,668 eighth-grade girls from 31 middle schools: 933 from urban settings, and 735 from rural settings. Forty-six percent of urban girls and 59% of rural girls were Black. One-way and two-way ANOVAs with school as a covariate were used to analyze the data. Results indicated that most differences were associated with race rather than setting. Black girls were less active than White girls, reporting significantly fewer 30-minute blocks of both vigorous and moderate-to-vigorous physical activity. Black girls also spent more time watching television, and had higher BMIs and greater prevalence of overweight than White girls. However, enjoyment of physical education and family involvement in physical activity were greater among Black girls titan White girls. Rural White girls and urban Black girls had more favorable attitudes toward physical activity. Access to sports equipment, perceived safety of neighborhood, and physical activity self-efficacy were higher in White girls than Black girls.

A microstrip Yagi antenna using EBG structure

[1] In this paper a detailed design, development and performances of a 5 GHz microstrip Yagi antenna, which uses a two-dimensional (2-D) electromagnetic band gap (EBG) structure in the ground plane, are presented. The results indicate that the use of the EBG structure improves the radiation pattern of the antenna. The cross polarization is suppressed by properly choosing the period and dimensions of EBGs. Also, the broadside gain is improved in comparison with the analogous antenna without the EBGs.

Australia and New Zealand satellite coverage using a microstrip patch reflectarray

This paper presents the design of Ku-band (12.25 12.75 GHz) dual-polarized reflectarrays for Optus BI satellites to obtain a contoured beam for Australia and New Zealand. The specified radiation pattern is synthesized using a phase-only synthesis method based on the concept of intersection approach. Having determined the phasing data, single- and double-layer reflectarrays ore designed using variable-size rectangular patches. The performances of the two reflectarrays are assessed by comparing their radiation patterns with the assumed pattern. (C) 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 321-325, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10. 1002/mop. 10907.

A genetic algorithm/method of moments approach to the optimization of an RF coil for MRI applications - Theoretical considerations - Abstract

A Combined Genetic Algorithm and Method of Moments design methods is presented for the design of unusual near-field antennas for use in Magnetic Resonance Imaging systems. The method is successfully applied to the design of an asymmetric coil structure for use at 190MHz and demonstrates excellent radiofrequency field homogeneity.

Discovering the Law Again: John Grisham, Ed Stevens and the Postmaterial Lawyer

This paper uses three films adapted from the novels of John Grisham, The Firm, The Rainmaker and A Time To Kill, as well as associated television series like Ed to map a vernacular theory of what I have termed the 'postmaterial' lawyer. Grisham's work has been the focus of much critique by legal scholars who suggests he hates lawyers, is critical of the concept of law, and provides 'outlandishly' happy endings. I will challenge these critiques and, in tracing the history of legal thrillers and trial movies, suggest that Grisham and the related texts' explorations of how a just practitioner can operate in an unjust system constitute a powerful interrogation of what law can be.

Overweight and obesity in Australia: The 1999-2000 Australian Diabetes, Obesity and Lifestyle Study (AusDiab)

Objective: To measure the prevalence of obesity in Australian adults and to examine the associations of obesity with socioeconomic and lifestyle factors. Design: AusDiab, a cross-sectional study conducted between May 1999 and December 2000, involved participants from 42 randomly selected districts throughout Australia. Participants: Of 20 347 eligible people aged greater than or equal to 25 years who completed a household interview, 11247 attended the physical examination at local survey sites (response rate, 55%). Main outcome measures: Overweight and obesity defined by body mass index (BMI; kg/m(2)) and waist circumference (cm); sociodemographic factors (including smoking, physical activity and television viewing time). Results: The prevalence of overweight and obesity (BMI greater than or equal to 25.0 kg/m(2); waist circumference greater than or equal to 80.0 cm [women] or greater than or equal to 94.0 cm [men]) in both sexes was almost 60%, defined by either BMI or waist circumference. The prevalence of obesity was 2.5 times higher than in 1980. Using waist circumference, the prevalence of obesity was higher in women than men (34.1% v 26.8%; P < 0.01). Lower educational status, higher television viewing time and lower physical activity time were each strongly associated with obesity, with television viewing time showing a stronger relationship than physical activity time. Conclusions: The prevalence of obesity in Australia has more than doubled in the past 20 years. Strong positive associations between obesity and each of television viewing time and lower physical activity time confirm the influence of sedentary lifestyles on obesity, and underline the potential benefits of reducing sedentary behaviour, as well as increasing physical activity, to curb the obesity epidemic.

Caminhos da sustentabilidade para o cinema brasileiro

O artigo pretende mostrar as dificuldades de sustentabilidade da atividade cinematogr??fica brasileira. Com base na an??lise da cadeia produtiva, na estrutura tribut??ria e nas falhas da legisla????o de incentivo fiscal, prop??e-se a exist??ncia de um ciclo vicioso de depend??ncia aos incentivos fiscais. Tendo em vista as dificuldades de acesso a salas de cinema, devido, entre outros fatores, ao baixo poder aquisitivo da popula????o e ?? concentra????o geogr??fica de cinemas nas grandes cidades, prop??e-se uma parceria efetiva entre cinema e televis??o, facilitada pela tecnologia digital. Isso implicar?? altera????es na legisla????o atual, bem como a cria????o de regras regulat??rias, como forma de ampliar o acesso de filmes nacionais ?? grade de programa????o televisiva e tamb??m de viabilizar, em termos industriais, essa atividade econ??mica.

A lei geral de comunica????o eletr??nica de massa e a qualidade da programa????o televisiva

O presente artigo pretende analisar a quest??o da qualidade da programa????o na televis??o brasileira a partir da proposta de um novo marco regulat??rio para o setor de comunica????o social eletr??nica. Essa nova lei, entre outras disposi????es, ir?? regulamentar o artigo 221 da Constitui????o Federal, que trata dos princ??pios pelos quais o conte??do televisivo deve pautar-se. Com isso, define-se qualidade levando-se em considera????o dois aspectos: diversidade e ressalvas ?? liberdade de express??o, ambos previstos na Constitui????o Federal. A partir dessa conceitua????o, prop??e-se a instrumentaliza????o do controle social sobre o conte??do televisivo e a garantia de meios para a diversidade da programa????o. Com rela????o ao primeiro aspecto, recomenda-se a atua????o transparente de uma futura ag??ncia reguladora e a implementa????o de mecanismo de controle individual da programa????o. No que tange ?? diversidade, ressalta-se a import??ncia do fortalecimento das televis??es p??blicas e medidas governamentais no sentido de estimular a multiprograma????o propiciada pelo advento da tecnologia digital.

Estado nutricional e estilo de vida em vegetarianos e onívoros, Grande Vitória-ES

Objetivo: Descrever e analisar o estado nutricional e aspectos do estilo de vida de vegetarianos e onívoros residentes na Grande Vitória/ES, na faixa etária de 35 a 64 anos de idade. Material E Métodos: Trata-se de estudo observacional híbrido de casos prevalentes com avaliação retrospectiva da exposição. Os grupos de expostos (134) e não expostos à dieta onívora típica ocidental (67) foram determinados no início da investigação. Foram coletados dados antropométricos, bioquímicos, de atividade física e alimentação através de questionário e 3 recordatórios de 24 horas e diagnosticados sobrepeso, Razão Cintura Quadril (RCQ) inadequada e hipercolesterolemia. Colesterol total e frações, triglicerídeos, ácido úrico, sódio e potássio urinários foram comparados entre os grupos, através do teste t de Student. Foi usado o teste qui-quadrado para comparar proporções, com =0,05. Resultados: Foram encontradas diferenças significativas em relação à ocupação. Duração da atividade física e tempo assistindo televisão e/ou utilizando computador foram maiores entre os onívoros. Os vegetarianos relataram práticas alimentares mais saudáveis e menor consumo de lipídios, proteínas e sódio. Os onívoros apresentaram maior risco de sobrepeso, RCQ inadequada e hipercolesterolemia (valores de P<0,0001). HDL-colesterol não foi diferente nos grupos. Conclusão: Os vegetarianos apresentaram perfil nutricional mais adequado e menor risco para os agravos crônicos estudados, apesar de pequena diferença no padrão de atividade física regular entre os grupos estudados.

O parlamento e a regulação das comunicações : estudo sobre a atividade legislativa do congresso nacional para a radiodifusão

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Comunicação, Programa de Pós-Graduação em Comunicação, 2016.

O tempo cerimonial na televisão ou a nostalgia programada

A televisão instaura diversos tipos de temporalidade: o tempo da informação, o da ficção e o dos arquivos. O Autor analisa, no âmbito do tempo dos média, o estatuto das cerimónias televisivas que se propõem imitar a lentidão e a continuidade próprias do ritual. Em certas ocasiões de dramatização, as cerimónias televisivas impõem à desordem própria do tempo da informação e do entretenimento televisivo a ordem inerente ao ritual, tentando introduzir no pequeno ecrã – ao lado dos concursos, dos jogos e das «notícias» – alguns fragmentos de um sagrado difuso mas unificador. Cerimónias como o funeral de Diana Spencer equivalem a uma suspensão da programação normal das televisões que unifica uma vasta audiência transnacional.