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Vencel, Michal. "Hodnocení kvality signálů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442585.
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This seminar work deals with the topic of evaluating the quality of ECG signals. The introductory chapters explain the basic characteristics of ECG signals - measurement, the form of the measured signal, methods of analysis. The cardiac physiology and pathology is presented. The most common types of noise that occur in ECG signals are also mentioned. Further, the reader is acquainted with the importance of the issue of evaluating the quality of ECG signals. In the practical part of the work, two own methods for ECG quality evaluation are presented. First, a brief theoretical introduction to the techniques used in the creation of methoda is given, followed by a description of the principle of algorithms. In order to compare the functionality of the proposed methods, three more methods from other authors are presented. Their principle is briefly described. In the final chapter, all methods are subjected to functionality testing. The results are examined and all methods are compared with each other.
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Rimal, Nischal. "Impact Localization Using Lamb Wave and Spiral FSAT." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1388672483.
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Efremovska, Irena, Sijme Geurts, and Scott Perret. "Leverage Points for Broader Diffusion of the FSSD." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3623.
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The intrinsic characteristics of the Framework for Strategic Sustainable Development (FSSD) make it useful in moving society towards sustainability. However, most of the change agents who work with the FSSD report that it is not diffused widely enough to have a systemic impact on society. The purpose of the study is to enable those who wish to foster such diffusion to be more effective in their efforts by giving them information they need to strategically plan those efforts. An ‘important factors for diffusion’ lens is constructed from Diffusion of Innovations theory and social marketing concepts, and verified with case studies of the diffusion of Biomimicry 3.8, GRI and Cradle to Cradle. 152 current barriers and enablers to broader diffusion of the FSSD are identified from interviews with 27 practitioners and a survey of 58 additional practitioners. These are scored against the lens to determine the current diffusibility of the FSSD, then distilled and influence flows between them mapped, to identify seven leverage points for broader diffusion. Interrelations between these leverage points, as well as other emergent themes, are discussed, conclusions are drawn, and further research suggested.irena.efrem@gmail.com; sijme@sijme.com; scott@notutopia.com
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Robertson, Jean-Baptiste. "Finite FSS for long wavelengths." Thesis, University of Kent, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544052.
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Lima, Antonio Cezar de Castro. "Convoluted element FSS and millimetre wave dichroics." Thesis, University of Kent, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385891.
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Montalv?o, Emanuele da Silva Rodrigues. "Uma proposta de FSS fractal com geometria simplificada." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15338.
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Previous issue date: 2010-12-21Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Frequency Selective Surfaces (FSS) are periodic structures in one or two dimensions that act as spatial filters, can be formed by elements of type conductors patches or apertures, functioning as filters band-stop or band-pass respectively. The interest in the study of FSS has grown through the years, because such structures meet specific requirements as low-cost, reduced dimensions and weighs, beyond the possibility to integrate with other microwave circuits. The most varied applications for such structures have been investigated, as for example, radomes, antennas systems for airplanes, electromagnetic filters for reflective antennas, absorbers structures, etc. Several methods have been used for the analysis of FSS, among them, the Wave Method (WCIP). Are various shapes of elements that can be used in FSS, as for example, fractal type, which presents a relative geometric complexity. This work has as main objective to propose a simplification geometric procedure a fractal FSS, from the analysis of influence of details (gaps) of geometry of the same in behavior of the resonance frequency. Complementarily is shown a simple method to adjust the frequency resonance through analysis of a FSS, which uses a square basic cell, in which are inserted two reentrance and dimensions these reentrance are varied, making it possible to adjust the frequency. For this, the structures are analyzed numerically, using WCIP, and later are characterized experimentally comparing the results obtained. For the two cases is evaluated, the influence of electric and magnetic fields, the latter through the electric current density vector. Is realized a bibliographic study about the theme and are presented suggestions for the continuation of this work
As Superf?cies Seletivas de Frequ?ncia (FSS) s?o estruturas peri?dicas em uma ou duas dimens?es que atuam como filtros espaciais, podendo ser formadas por elementos do tipo patches condutores ou aberturas, funcionando como filtros rejeita-faixa ou passa-faixa, respectivamente. O interesse no estudo das FSS tem crescido atrav?s dos anos, pois tais estruturas atendem a requisitos espec?ficos como baixo custo, dimens?es e pesos reduzidos, al?m da possibilidade de se integrar com outros circuitos de micro-ondas. As mais variadas aplica??es para tais estruturas t?m sido investigadas, como por exemplo, radomes, sistemas de antenas para avi?es, filtros eletromagn?ticos para antenas refletoras, estruturas absorvedoras, etc. V?rios m?todos t?m sido utilizados para a an?lise de FSS, dentre eles, o M?todo das Ondas (WCIP). S?o diversas as formas de elementos que podem ser utilizados em FSS, como por exemplo, os do tipo fractal, que apresenta uma relativa complexidade geom?trica. Este trabalho tem como objetivo principal propor um procedimento de simplifica??o geom?trica de uma FSS fractal, a partir da an?lise da influ?ncia dos detalhes (fendas) da geometria da mesma no comportamento da frequ?ncia de resson?ncia. De forma complementar ? mostrado um m?todo simples de ajustar a frequ?ncia de resson?ncia atrav?s da an?lise de uma FSS, que utiliza uma c?lula b?sica retangular, na qual s?o inseridas duas reentr?ncias e as dimens?es dessas reentr?ncias s?o variadas, tornando poss?vel o ajuste da frequ?ncia. Para isso, as estruturas s?o analisadas numericamente, utilizando o WCIP, e posteriormente s?o caracterizadas experimentalmente, comparando-se os resultados obtidos. Para os dois casos ? avaliada, a influ?ncia dos campos el?trico e magn?tico, este ?ltimo atrav?s do vetor densidade de corrente el?trica. ? realizado um estudo bibliogr?fico a cerca do tema e s?o apresentadas sugest?es para a continuidade deste trabalho
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Ferreira, Hillner. "MATRIOSKA: UMA PROPOSTA DE GEOMETRIA PARA FSS MULTIBANDAS." reponame:Repositório Institucional do IFPB, 2016. http://repositorio.ifpb.edu.br/jspui/handle/177683/234.
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O progresso tecnol?gico e o aumento da demanda por servi?os em sistemas de telecomunica??es v?m, ao longo das ?ltimas d?cadas, fomentando o desenvolvimento de equipamentos com tamanhos cada vez menores e mais integrados. Essa tend?ncia de unir, em um s? aparelho, diversas tecnologias, tem estimulado o estudo de novas estruturas multibanda. Exibindo a propriedade de um filtro, as superf?cies seletivas em frequ?ncia, FSS, tornaram-se tema de extensivas pesquisas associadas ? opera??o em m?ltiplas frequ?ncias. Como resultado, estas estruturas podem ser encontradas atualmente em um grande n?mero de aplica??es que v?o desde as mais tradicionais, como as tampas do forno de micro-ondas, at? as mais recentes, como em bloqueadores de rede sem fio, etiquetas RFID sem chips, antenas inteligentes, dentre outras. Com objetivo de contribuir para o estudo das FSS, este trabalho ? resultado da investiga??o te?rica e experimental de uma nova proposta de geometria. Inspirado nas famosas bonecas russas matrioskas, o modelo geom?trico desenvolvido apresenta caracter?sticas particularmente interessantes como, por exemplo, a possibilidade de obten??o de frequ?ncias de resson?ncia mais baixas e em maior quantidade, sem comprometer, contudo, a ?rea limite da c?lula unit?ria inicialmente definida. Para an?lise num?rica dessa geometria, o comportamento em frequ?ncia foi obtido a partir do m?todo dos momentos (MoM) utilizando o programa computacional Ansoft Designer. A valida??o e an?lise experimental dos resultados foram conseguidas por meio da constru??o de prot?tipos e medi??es realizadas no Laborat?rio de Medidas em Micro-ondas do GTEMA/IFPB. Os resultados foram discutidos e o comportamento ressonante da FSS estudado, sendo apresentadas sugest?es para trabalhos futuros.
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Cruz, Josiel do Nascimento. "CARACTERIZA??O DE FSS COM GEOMETRIA MATRIOSKA ABERTA." reponame:Repositório Institucional do IFPB, 2014. http://repositorio.ifpb.edu.br/jspui/handle/177683/240.
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Nos ?ltimos anos os avan?os tecnol?gicos t?m impulsionado as comunica??es sem fio, com uma crescente oferta de servi?os e aplica??es, sendo um desafio para os engenheiros de telecomunica??es. Com caracter?sticas que despertam interesse nos sistemas de comunica??es, as superf?cies seletivas em frequ?ncia, FSS, t?m sido tema de v?rias pesquisas, especialmente por poder apresentar opera??o em m?ltiplas frequ?ncias e com dimens?es reduzidas. As aplica??es com FSS s?o diversas, pode-se destacar algumas, como em tampas de forno de micro-ondas, que ? umas das mais tradicionais, ou mais recentemente, em bloqueadores de redes sem fio, etiquetas RFID sem chip, antenas inteligentes, entre outras aplica??es. Buscando contribuir para o estudo das FSS, este trabalho d? continuidade ao estudo da geometria matrioska, com a an?lise da FSS com a geometria matrioska aberta. Essa geometria ? inspirada nas famosas bonecas russas matrioskas e apresenta caracter?sticas que despertam interesse como, por exemplo, a possibilidade de obten??o de frequ?ncias de resson?ncias mais baixas, assim como m?ltiplas resson?ncias, sem comprometer a ?rea limite da c?lula unit?ria. Neste trabalho foi realizada uma an?lise da estrutura matrioska aberta, a partir da distribui??o da densidade de corrente el?trica, possibilitando um melhor entendimento do comportamento ressonante da estrutura. Foi tamb?m realizada uma an?lise da matrioska aberta, levando em considera??o o seu comprimento efetivo e a posi??o da fenda. Para an?lise num?rica da geometria matrioska aberta, o comportamento em frequ?ncia foi obtido pelo m?todo dos momentos (MoM) utilizando o programa comercial Ansoft DesignerTM. A valida??o e an?lise experimental dos resultados foram conseguidas por meio da constru??o de prot?tipos e as medi??es foram realizadas no Laborat?rio de Medidas em Micro-ondas do GTEMA/IFPB. Foi obtida uma concord?ncia muito boa entre os resultados num?ricos e experimentais.
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Ferreira, Hillner de Paiva Almeida. "MATRIOSKA: UMA PROPOSTA DE GEOMETRIA PARA FSS MULTIBANDAS." reponame:Repositório Institucional do IFPB, 2014. http://repositorio.ifpb.edu.br/jspui/handle/177683/244.
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O progresso tecnol?gico e o aumento da demanda por servi?os em sistemas de telecomunica??es v?m, ao longo das ?ltimas d?cadas, fomentando o desenvolvimento de equipamentos com tamanhos cada vez menores e mais integrados. Essa tend?ncia de unir, em um s? aparelho, diversas tecnologias, tem estimulado o estudo de novas estruturas multibanda. Exibindo a propriedade de um filtro, as superf?cies seletivas em frequ?ncia, FSS, tornaram-se tema de extensivas pesquisas associadas ? opera??o em m?ltiplas frequ?ncias. Como resultado, estas estruturas podem ser encontradas atualmente em um grande n?mero de aplica??es que v?o desde as mais tradicionais, como as tampas do forno de micro-ondas, at? as mais recentes, como em bloqueadores de rede sem fio, etiquetas RFID sem chips, antenas inteligentes, dentre outras. Com objetivo de contribuir para o estudo das FSS, este trabalho ? resultado da investiga??o te?rica e experimental de uma nova proposta de geometria. Inspirado nas famosas bonecas russas matrioskas, o modelo geom?trico desenvolvido apresenta caracter?sticas particularmente interessantes como, por exemplo, a possibilidade de obten??o de frequ?ncias de resson?ncia mais baixas e em maior quantidade, sem comprometer, contudo, a ?rea limite da c?lula unit?ria inicialmente definida. Para an?lise num?rica dessa geometria, o comportamento em frequ?ncia foi obtido a partir do m?todo dos momentos (MoM) utilizando o programa computacional Ansoft Designer. A valida??o e an?lise experimental dos resultados foram conseguidas por meio da constru??o de prot?tipos e medi??es realizadas no Laborat?rio de Medidas em Micro-ondas do GTEMA/IFPB. Os resultados foram discutidos e o comportamento ressonante da FSS estudado, sendo apresentadas sugest?es para trabalhos futuros.
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Antonopoulos, C. "Studies of FSS for microwave and millimeter wave bands." Thesis, University of Kent, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245689.
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Zabri, Siti Normi. "Study of thin resistively loaded FSS based microwave absorbers." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.676498.
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The purpose of this study was to develop new FSS based microwave absorber designs to minimise the physical thickness, increase the bandwidth and provide radar backscatter suppression that is independent of the wave polarization at large incident angles. A new low cost, accurate and rapid printing technique is employed to pattern the periodic arrays with the precise surface resistance required for each of the FSS elements to optimize the performance of this class of absorber. The electromagnetic behaviour of five new FSS based structures, two standalone arrays, and three absorber arrangements, have been studied using CST Microwave Studio software. The FSS structures consist of two closely spaced arrays of rings with the conductor split at one or two locations to provide independent control of the resonances. By careful design these are shown to exhibit coincident spectral transmission responses in the TE and TM plane. Based on this design methodology, a very thin 4-layer metal backed resistively loaded rectangular loop FSS absorber which works from 0° - 22.5° is shown to give a wide band performance that is independent of the orientation of the impinging signals. To reduce the manufacturing complexity, a single layer FSS absorber which operates at 45° incidence has been designed to give a polarisation independent performance by employing an array of rectangular split loops with discrete pairs of resistive elements of unequal value inserted at the midpoint of the four sides. A major increase in bandwidth is obtained from a single layer FSS absorber which is composed of an array of nested hexagonal loops. Moreover the use of the same surface resistance for all four elements in the unit cell is shown to significantly simplify the construction of the structure which was designed to provide radar cloaking from 0° to 45° incidence. A new manufacturing strategy is presented, where the required surface resistances are obtained by employing an ink-jet printer to simultaneously pattern the FSS elements on the substrate and digitally control the dot density of the nano silver ink and aqueous vehicle mixture.
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Mani?oba, Robson Hebraico Cipriano. "Estudo do acoplamento entre superf?cies seletivas de frequ?ncia assim?tricas em estruturas de multicamadas." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15185.
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Previous issue date: 2012-06-18Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
This work presents the development of new microwaves structures, filters and high gain antenna, through the cascading of frequency selective surfaces, which uses fractals D?rer and Minkowski patches as elements, addition of an element obtained from the combination of the other two simple the cross dipole and the square spiral. Frequency selective surfaces (FSS) includes a large area of Telecommunications and have been widely used due to its low cost, low weight and ability to integrate with others microwaves circuits. They re especially important in several applications, such as airplane, antennas systems, radomes, rockets, missiles, etc. FSS applications in high frequency ranges have been investigated, as well as applications of cascading structures or multi-layer, and active FSS. In this work, we present results for simulated and measured transmission characteristics of cascaded structures (multilayer), aiming to investigate the behavior of the operation in terms of bandwidth, one of the major problems presented by frequency selective surfaces. Comparisons are made with simulated results, obtained using commercial software such as Ansoft DesignerTM v3 and measured results in the laboratory. Finally, some suggestions are presented for future works on this subject
Este trabalho apresenta o desenvolvimento de novas estruturas de micro-ondas, filtros multi-banda ou banda larga, atrav?s do cascateamento de superf?cies seletivas em frequ?ncia, que usa patches fractais de D?rer pentagonal e Minkowski como elementos, al?m de um elemento obtido a partir da combina??o de outros dois mais simples que s?o o dipolo em cruz e a espira quadrada. Superf?cies seletivas em frequ?ncia (FSS) abrangem uma grande ?rea das Telecomunica??es e t?m sido largamente utilizadas devido a seu baixo custo, peso reduzido e possibilidade de se integrar com outros circuitos de micro-ondas. Elas s?o especialmente importantes em diversas aplica??es, como avi?es, sistemas de antenas, radomes, foguetes, m?sseis, etc. Aplica??es de FSS em faixas de frequ?ncia elevadas t?m sido investigadas, assim como aplica??es destas estruturas em cascata ou multicamadas, FSS ativas. Nesse trabalho, s?o apresentados resultados simulados e medidos para as caracter?sticas de transmiss?o de estruturas cascateadas (multicamadas), com intuito de investigar o comportamento do funcionamento em termos de largura de banda, um dos grandes problemas apresentados por superf?cies seletivas em frequ?ncia. S?o feitas compara??es entre resultados simulados, obtidos utilizando software comercial como Ansoft DesignerTM v3 e resultados medidos em laborat?rio. S?o apresentadas, ainda, sugest?es de continuidade do trabalho
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Conraud, Guillaume. "Fédérations sportives et identités : une analyse sociologique par le prisme de la FSGT." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS012.
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En 2014, la Fédération sportive et gymnique du travail fêtait ses 80 ans. Cette période « anniversaire » et l’histoire accumulée par l’organisation poussèrent ses dirigeants à s’interroger sur « ses valeurs » et son « identité ». Ce contexte fut propice à la mise en place d’une convention industrielle de formation par la recherche (CIFRE).Derrière ces termes génériques et ce projet se cache une réalité complexe pour des fédérations qui ont le sentiment que se distendent les rapports avec leurs comités, leurs clubs, leurs bénévoles et surtout avec leurs licenciés. Dans un système sportif où le modèle associatif ainsi que les modalités d’engagement évoluent et où les concurrences s’affirment, ces organisations sont amenées à se questionner sur la légitimité de leur projet fédéral et sur leur capacité à influencer les pratiques sportives et associatives développées localement.Une immersion de plus de trois années au sein de la FSGT a permis de partager le quotidien des acteurs de cette fédération, de les observer et de les interroger pour comprendre l’évolution de ce type d’organisations.Afin d’approfondir ce regard immergé, à travers ce que nous avons appelé un « effet miroir » , nous avons mis en perspective le cas de la FSGT avec quatre autres fédérations affinitaires (Fédération sportive et culturelle de France, Union française des oeuvres laïques d’éducation physique) et délégataires (Fédération française de la montagne et de l’escalade, Fédération française de football).Cette thèse traite ainsi du rapport des fédérations avec les différents types d’acteurs qui les animent, du niveau local au siège national. Elle propose également une lecture des processus « d’innovation » en oeuvre dans ces organisations, de la manière dont elles font évoluer leur fonctionnement, leur rapport à la démocratie associative, leur projet politique, ainsi que les activités sportives développées au sein des clubs affiliés (notamment à travers un focus sur les activités escalade et football)In 2014, the Fédération sportive et gymnique du travail (FSGT, aka Labour Sports and Gymnastic Federation) celebrated its 80th birthday. The anniversary year was the occasion for leadership to reflect upon the organisation’s “values” and “identity”, building on its rich history. To explore these questions, FSGT entered into a CIFRE (research training industrial convention) partnership with the author.A complex reality hides behind these generic terms: there is a perception among federations that relationships between federations and their committees, clubs, volunteers, and members are wearing off. Sports federations are questioning the legitimacy of the federative project and their ability to influence local sports and associative practices in the French sports system, where sports associations and engagement models are constantly evolving, and competition is rising.This three-year immersive work experience within FSGT exposed the author to the daily life of the federation’s actors, to observe them, and interact with them, to try and understand the evolution of this type of organisation.The author used what he defines as a “mirror effect” to further explore this immersive outlook onto sports federations, putting FSGT in perspective with two peer-based (Fédération sportive et Culturelle de France and Union française des oeuvres laïques d’éducation physique) and two delegate-based federations (Fédération française de la montagne et de l’escalade and Fédération française de football).In this thesis, the author explores the relationship of sports federations with the different kinds of actors they comprise, at local and national level. The author also analyses innovation processes in place in these organisations, their evolution, their rapport to association democracy, their political project, as well as sports activities developed within affiliated clubs (with a special focus on rock climbing and football activities)
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Utkucan, Ece, Matthew Lobach, and Wyeth Larson. "Sustainable E-waste Management : Using the FSSD in a Case study at NUR." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2481.
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This thesis explores how to apply an approach of strategic sustainable development to e-waste management through a case study at the National University of Rwanda (NUR). Interviews and surveys were conducted, and workshops and presentations were hosted during a site visit to NUR. No e-waste management system is in place in Rwanda, while the country is working to increase ICT capacity. At NUR, awareness of e-waste challenges is low, and management currently consists of storage and limited low-tech pre-processing. Suggested actions were prioritized and delivered to NUR in an action plan under three project categories: project core, e-waste management, and e-waste education and research with the aim of establishing a pilot project of e-waste management to make NUR an e-waste leader. A Framework for Strategic Sustainable Development was used to ensure e-waste is managed in a strategic way that leads to an e-waste management approach that could exist in a sustainable society. This research concludes that strategic sustainable e-waste management is possible at NUR and presents six theme areas to guide the development of an e-waste project with a systems perspective.
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McCune, Joel D. "An investigation of flow and IZOF utilization of FSS-2." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4620.
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Thesis (M.S.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 9, 2007) Includes bibliographical references.
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Su, Hansheng. "Development of optically controlled FSS and antenna using photoconductive approach." Thesis, Queen Mary, University of London, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610933.
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Kopecki, Ianina. "Calculational approach to FST-hemispheres for multiparametrical Benthos Habitat modelling." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-38677.
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Silva, Andr? Nascimento da. "Caracteriza??o de FSS com Geometria em Forma de U." reponame:Repositório Institucional do IFPB, 2016. http://repositorio.ifpb.edu.br/jspui/handle/177683/275.
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Nos ?ltimos anos, com a diversidade das comunica??es sem fio, principalmente em dispositivos como telefone m?vel, TV digital, tablets, RFID, etc., nos quais um ?nico equipamento pode operar em diferentes bandas de frequ?ncia, um cont?nuo desafio ? imposto aos engenheiros no projeto de antenas em micro-ondas. Uma das estruturas que tem recebido consider?vel aten??o s?o as superf?cies seletivas em frequ?ncia (Frequency Selective Surface - FSS), devido ?s diversas aplica??es no espectro de frequ?ncia, incluindo micro-ondas e ondas milim?tricas. Afim de se obter dimens?es reduzidas e resposta em frequ?ncia espec?fica, diversas geometrias s?o estudadas, incluindo elementos simples ou uma combina??o dos mesmos. Recentemente, as FSS t?m sido empregadas em redes sem fio como sensores passivos e sistemas de identifa??o por r?dio frequ?ncia sem chip (chipless). Neste trabalho ? apresentada a an?lise da geometria em forma de U para FSS. Trata-se de uma geometria geralmente usada em antenas planares. A ideia principal ? averiguar como as respostas em frequ?ncia das FSS variam em fun??o da geometria em forma de U, seja como fenda, slot, ou como metaliza??o. Para a an?lise num?rica das FSS, um dos m?todos adotados foi o M?todo das Ondas, mais conhecido na literatura como WCIP (Wave Concept Iterative Procedure). As FSS apresentaram boas caracter?sticas de miniaturiza??o e multibanda, verificando-se na redu??o da frequ?ncia de resson?ncia, e no surgimento de novas resson?ncias, sem altera??o dos limites da c?lula unit?ria. S?o propostas equa??es aproximadas de projeto e apresentados resultados num?ricos e experimentais. Pretende-se a partir destas an?lises, colocar tal investiga??o como potencial recurso no desenvolvimento de dispositivos para aplica??es que necessitem de elementos compactos, e de opera??o multibanda, a exemplo da tecnologia RFID sem chip e antenas inteligentes.
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Silva, Andr? "Caracteriza??o de FSS com Geometria em Forma de U." reponame:Repositório Institucional do IFPB, 2016. http://repositorio.ifpb.edu.br/jspui/handle/177683/233.
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Nos ?ltimos anos, com a diversidade das comunica??es sem fio, principalmente em dispositivos como telefone m?vel, TV digital, tablets, RFID, etc., nos quais um ?nico equipamento pode operar em diferentes bandas de frequ?ncia, um cont?nuo desafio ? imposto aos engenheiros no projeto de antenas em micro-ondas. Uma das estruturas que tem recebido consider?vel aten??o s?o as superf?cies seletivas em frequ?ncia (Frequency Selective Surface - FSS), devido ?s diversas aplica??es no espectro de frequ?ncia, incluindo micro-ondas e ondas milim?tricas. A fim de se obter dimens?es reduzidas e resposta em frequ?ncia espec?fica, diversas geometrias s?o estudadas, incluindo elementos simples ou uma combina??o dos mesmos. Recentemente, as FSS t?m sido empregadas em redes sem fio como sensores passivos e sistemas de identifa??o por r?dio frequ?ncia sem chip (chipless). Neste trabalho ? apresentada a an?lise da geometria em forma de U para FSS. Trata-se de uma geometria geralmente usada em antenas planares. A ideia principal ? averiguar como as respostas em frequ?ncia das FSS variam em fun??o da geometria em forma de U, seja como fenda, slot, ou como metaliza??o. Para a an?lise num?rica das FSS, um dos m?todos adotados foi o M?todo das Ondas, mais conhecido na literatura como WCIP (Wave Concept Iterative Procedure). As FSS apresentaram boas caracter?sticas de miniaturiza??o e multibanda, verificando-se na redu??o da frequ?ncia de resson?ncia, e no surgimento de novas resson?ncias, sem altera??o dos limites da c?lula unit?ria. S?o propostas equa??es aproximadas de projeto e apresentados resultados num?ricos e experimentais. Pretende-se a partir destas an?lises, colocar tal investiga??o como potencial recurso no desenvolvimento de dispositivos para aplica??es que necessitem de elementos compactos, e de opera??o multibanda, a exemplo da tecnologia RFID sem chip e antenas inteligentes.
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Silva, Andr? Nascimento da. "CARACTERIZA??O DE FSS COM GEOMETRIA EM FORMA DE U." reponame:Repositório Institucional do IFPB, 2014. http://repositorio.ifpb.edu.br/jspui/handle/177683/235.
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Nos ?ltimos anos, com a diversidade das comunica??es sem fio, principalmente em dispositivos como telefone m?vel, TV digital, tablets, RFID, etc., nos quais um ?nico equipamento pode operar em diferentes bandas de frequ?ncia, um cont?nuo desafio ? imposto aos engenheiros no projeto de antenas em micro-ondas. Uma das estruturas que tem recebido consider?vel aten??o s?o as superf?cies seletivas em frequ?ncia (Frequency Selective Surface - FSS), devido ?s diversas aplica??es no espectro de frequ?ncia, incluindo micro-ondas e ondas milim?tricas. A fim de se obter dimens?es reduzidas e resposta em frequ?ncia espec?fica, diversas geometrias s?o estudadas, incluindo elementos simples ou uma combina??o dos mesmos. Recentemente, as FSS t?m sido empregadas em redes sem fio como sensores passivos e sistemas de identifa??o por r?dio frequ?ncia sem chip (chipless). Neste trabalho ? apresentada a an?lise da geometria em forma de U para FSS. Trata-se de uma geometria geralmente usada em antenas planares. A ideia principal ? averiguar como as respostas em frequ?ncia das FSS variam em fun??o da geometria em forma de U, seja como fenda, slot, ou como metaliza??o. Para a an?lise num?rica das FSS, um dos m?todos adotados foi o M?todo das Ondas, mais conhecido na literatura como WCIP (Wave Concept Iterative Procedure). As FSS apresentaram boas caracter?sticas de miniaturiza??o e multibanda, verificando-se na redu??o da frequ?ncia de resson?ncia, e no surgimento de novas resson?ncias, sem altera??o dos limites da c?lula unit?ria. S?o propostas equa??es aproximadas de projeto e apresentados resultados num?ricos e experimentais. Pretende-se a partir destas an?lises, colocar tal investiga??o como potencial recurso no desenvolvimento de dispositivos para aplica??es que necessitem de elementos compactos, e de opera??o multibanda, a exemplo da tecnologia RFID sem chip e antenas inteligentes.
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Savia, S. B. "Computer-aided study of FSS and some applications of ferroic materials." Thesis, University of Kent, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322722.
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Moreira, Ricardo C?sar de Oliveira. "Antenas planares integradas com FSSs para aplica??es em sistemas de comunica??es sem fio." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15438.
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Previous issue date: 2012-04-18Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
This work presents a theoretical and experimental analysis about the properties of microstrip antennas with integrated frequency selective surfaces (Frequency Selective Surface - FSS). The integration occurs through the insertion of the FSS on ground plane of microstrip patch antenna. This integration aims to improve some characteristics of the antennas. The FSS using patch-type elements in square unit cells. Specifically, the simulated results are obtained using the commercial computer program CST Studio Suite? version 2011. From a standard antenna, designed to operate in wireless communication systems of IEEE 802.11 a / b / g / n the dimensions of the FSS are varied to obtain an optimization of some antenna parameters such as impedance matching and selectivity in the operating bands. After optimization of the investigated parameters are built two prototypes of microstrip patch antennas with and without the FSS ground plane. Comparisons are made of the results with the experimental results by 14 ZVB network analyzer from Rohde & Schwarz ?. The comparison aims to validate the simulations performed and show the improvements obtained with the FSS in integrated ground plane antenna. In the construction of prototypes, we used dielectric substrates of the type of Rogers Corporation RT-3060 with relative permittivity equal to 10.2 and low loss tangent. Suggestions for continued work are presented
Este trabalho apresenta uma investiga??o te?rica e experimental sobre as propriedades das antenas de microfita integradas com superf?cies seletivas em frequ?ncia (Frequency Selective Surface FSS). A integra??o se d? por meio da inser??o da FSS no plano de terra da antena patch de microfita. Essa integra??o visa a melhoria de algumas caracter?sticas das antenas como, por exemplo, ganho, largura de banda, dentre outras. As FSS utilizam elementos do tipo patch quadrado nas c?lulas unit?rias. Especificamente, os resultados simulados s?o obtidos utilizando-se o programa computacional comercial CST Studio Suite? vers?o 2011. A partir de uma antena padr?o, projetada para operar em sistemas de comunica??es sem fio dos padr?es IEEE 802.11 a/b/g/n, as dimens?es da FSS s?o variadas de forma a obter uma otimiza??o de alguns par?metros da antena, como casamento de imped?ncia e seletividade nas bandas de opera??o. Ap?s a otimiza??o dos par?metros investigados, s?o constru?dos dois prot?tipos de antenas patch de microfita com e sem a FSS no plano de terra. S?o feitas compara??es dos resultados simulados com os resultados experimentais obtidos pelo analisador de rede ZVB 14 da Rohde & Schwarz?. A compara??o visa validar as simula??es efetuadas e mostrar as melhorias obtidas com a FSS integrada no plano de terra da antena. Na constru??o dos prot?tipos, foram utilizados substratos diel?tricos da Rogers Corporation do tipo RT-3060 com permissividade relativa igual a 10,5 e baixa tangente de perdas. Sugest?es de continuidade do trabalho s?o apresentadas
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Hogenboom, Michaela, Amy Mireault, and Thaela Stolz. "Areas of Inquiry : Guiding FSSD practitioners at the beginning of a change initiative towards sustainability." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2852.
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This research aims to support sustainability practitioners at the beginning of a change initiative towards sustainability to increase the success of the change. Moving towards sustainability is a complex journey and requires radical and structural transformational change in companies. Mutual understanding of the company and the practitioner is required to design a suitable change process. Existing tools related to sustainability, change management, corporate analysis and assessment were analyzed. In addition, practitioners in organizational change and sustainability were interviewed. Identified were eight Areas of Inquiry for the practitioner to focus on at the initial stage of an engagement: Vision; Purpose and Commitment; Urgency, Importance and Business Case; Level of Integration of Sustainability; Business Goals and Strategy; Culture and Capacities; Communication and Stakeholder Engagement; Measurement and Reporting. These areas form a platform for dialogue to guide sustainability practitioners in gaining understanding of the organizational change capacities and sustainability within the company and, in doing so, contributes to addressing the sustainability challenge at large.
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Carvalho, Rafaela Gomes Gon?alves de. "Desenvolvimento de FSS mecanicamente reconfigur?vel para aplica??es em micro-ondas." PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA EL?TRICA E DE COMPUTA??O, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/23547.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
A reconfigurabilidade ? uma caracter?stica muito importante nos sistemas modernos de comunica??o, pois permite que uma mesma estrutura se adapte aos diferentes cen?rios de uma mesma aplica??o, como por exemplo, radomes, r?dio cognitivo, e telas adaptativas que bloqueiam transmiss?es sem fio indesejadas. Essa caracter?stica pode ser alcan?ada mediante m?todos tradicionais, como o uso de dispositivos semicondutores ativos (diodos PIN, Schottky) ou capacitores vari?veis acoplados a cada elemento b?sico da superf?cie seletiva de frequ?ncia (FSS), sendo necess?rio o uso de um circuito separado para alimentar esses dispositivos. No entanto, estes m?todos requerem um n?mero elevado de elementos ativos, o que aumenta a complexidade e o custo de fabrica??o, abrindo espa?o para o surgimento de t?cnicas mais simples e robustas quanto ? seletividade, como a reconfigurabilidade mec?nica. Este trabalho consiste no desenvolvimento de uma superf?cie seletiva de frequ?ncia (FSS) reconfigur?vel, para operar na banda X, formada por patches condutores triangulares impressos em uma camada de diel?trico de fibra de vidro (FR-4). A FSS desenvolvida permite a reconfigura??o da frequ?ncia de resson?ncia a partir da varia??o do ?ngulo da onda incidente na estrutura, com polariza??o TE, e pode ser aplicada em sistemas de comunica??o via sat?lite a partir de uma interface microcontrolada. A an?lise da estrutura da FSS ? efetuada atrav?s do software Ansoft Designer do M?todo das Ondas ? WCIP.
Reconfigurability is a very important feature in modern communication systems because it allows the same structure to adapt to different scenarios of the same application, such as radomes, cognitive radio, and adaptive screens that block unwanted wireless transmissions. This characteristic can be achieved by traditional methods, such as the use of active semiconductor devices (PIN and Schottky diodes) or variable capacitors coupled to each basic element of the frequency selective surface (FSS), requiring the use of a separate circuit to feed these components. However, these methods require a high number of active elements, which increases the complexity and cost of manufacturing, opening space for the emergence of simpler and more robust techniques for selectivity, such as mechanical reconfigurability. This work consists of the development of a reconfigurable frequency selective surface (FSS), to operate in the X-band, composed of triangular patch elements printed on a dielectric layer of fiberglass (FR-4). The developed FSS allows the reconfiguration of the resonant frequency from the variation of the angle of the incident wave in the structure, in the TE polarization, and can be applied in satellite communication systems through a microcontrolled interface. The analysis of the structure of the FSS is done through Ansoft Designer software and WCIP method.
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Severino, Paula Rita de Sousa. "Food defense e a sua relação com as normas IFS V6, BRC V7 e FSSC 22000." Master's thesis, ISA-UL, 2016. http://hdl.handle.net/10400.5/13372.
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Mestrado em Engenharia Alimentar - Qualidade e Segurança Alimentar - Instituto Superior de Agronomia - ULOs sucessivos acontecimentos terroristas no setor alimentar, verificados ao longo de décadas levaram a que, pela primeira vez, no domínio alimentar, emergisse nos EUA o conceito de defesa alimentar, cujo objetivo é adotar medidas preventivas da contaminação intencional de produtos, onde indivíduos motivados ideologicamente recorrem a agentes (biológicos, químicos, físicos ou radiológicos) com o intuito de causar prejuízos às organizações, governos ou à população em geral. O reconhecimento da sua importância na cadeia alimentar promoveu a difusão deste conceito através de normas certificáveis como a IFS Food versão 6, BRC Food versão 7 e FSSC 22000 e o desenvolvimento de novas metodologias. Apesar de ser uma iniciativa recente, verifica-se a nível mundial uma forte adoção das práticas de defesa alimentar, embora em Portugal esta adoção se tem revelado de pequena amplitude. No presente estudo foi feita uma análise do conceito de defesa alimentar, a sua importância nas organizações e a correlação com os referenciais de segurança alimentar. Para tal, procedeu-se a uma sistematização das metodologias existentes para proteger as organizações da contaminação intencional, adulteração e fraude alimentar, das quais nomeiam-se o CARVER+Shock, TACCP, VACCP, HACCDP, HARPC e ORM. Apesar das diferentes especificações reveladas pelos sistemas, verifica-se que convergem para o mesmo fim, adotar procedimentos que auxiliem as organizações a avaliar potenciais vulnerabilidades, ameaças e riscos inerentes. O estudo permitiu identificar os sistemas mais adequados a implementar para uma organização que seja certificada numa das três normas (BRC, IFS, FSSC 22000). Constatou-se da análise efetuada que o TACCP foi o método que revelou ser o mais completo para atender aos requisitos referentes à defesa alimentar impostos nas normas em estudo
N/A
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Haghighattalab, Armin. "Finite Element Modeling of Spiral Frequency Steerable Acoustic Transducers (FSATs) for guided waves based Structural Health Monitoring of plate-like structures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
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Structural Health Monitoring (SHM) is an emerging area of research associated to improvement of maintainability and the safety of aerospace, civil and mechanical infrastructures by means of monitoring and damage detection. Guided wave structural testing method is an approach for health monitoring of plate-like structures using smart material piezoelectric transducers. Among many kinds of transducers, the ones that have beam steering feature can perform more accurate surface interrogation. A frequency steerable acoustic transducer (FSATs) is capable of beam steering by varying the input frequency and consequently can detect and localize damage in structures.
Guided wave inspection is typically performed through phased arrays which feature a large number of piezoelectric transducers, complexity and limitations. To overcome the weight penalty, the complex circuity and maintenance concern associated with wiring a large number of transducers, new FSATs are proposed that present inherent directional capabilities when generating and sensing elastic waves. The first generation of Spiral FSAT has two main limitations. First, waves are excited or sensed in one direction and in the opposite one (180 ̊ ambiguity) and second, just a relatively rude approximation of the desired directivity has been attained. Second generation of Spiral FSAT is proposed to overcome the first generation limitations.
The importance of simulation tools becomes higher when a new idea is proposed and starts to be developed. The shaped transducer concept, especially the second generation of spiral FSAT is a novel idea in guided waves based of Structural Health Monitoring systems, hence finding a simulation tool is a necessity to develop various design aspects of this innovative transducer. In this work, the numerical simulation of the 1st and 2nd generations of Spiral FSAT has been conducted to prove the directional capability of excited guided waves through a plate-like structure.
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Santos, Albanisa Felipe dos. "Desenvolvimento te?rico e experimental de FSS com elementos fractais de Gosper em estruturas de multicamadas." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br/handle/123456789/19472.
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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq
Neste trabalho, as propriedades de auto-similaridade dos fractais s?o exploradas para o desenvolvimento de superf?cies seletivas de frequ?ncia (Frequency Selectives Surfaces - FSS) com v?rias bandas de rejei??o. Em particular, s?o considerados fractais de Gosper, na defini??o dos formatos dos elementos das FSS. Por conta da dificuldade de impress?o de detalhes dos elementos das FSS, s?o considerados apenas elementos pr?-fractais, com at? tr?s itera??es fractais. As simula??es foram realizadas com o uso do programa comercial Ansoft Designer. Para fins de valida??o de resultados, foram constru?dos v?rios prot?tipos de FSS com elementos pr?-fractais. No processo de fabrica??o, os formatos dos elementos pr?-fractais foram desenhados com aux?lio do programa Corel Draw. Os prot?tipos constru?dos foram medidos atrav?s de um analisador de redes vetorial (modelo N3250A, da Agilent Technologies). A utiliza??o de elementos pr?-fractais nas estruturas de FSS consideradas, permitiu verificar que o aumento do n?vel fractal possibilita a redu??o do tamanho dos elementos, por?m reduz a largura de banda das mesmas. Neste sentido, ? tamb?m investigado o efeito produzido pelo cascateamento de estruturas de FSS na largura de banda. Foi observado que o uso de estruturas cascateadas, al?m de aumentar a largura de banda, permitiu, em alguns casos, a obten??o de at? respostas em frequ?ncia com tr?s bandas de opera??o entre 6 GHz e 15 GHz.
The fractal self-similarity property is studied to develop frequency selective surfaces (FSS) with several rejection bands. Particularly, Gosper fractal curves are used to define the shapes of the FSS elements. Due to the difficulty of making the FSS element details, the analysis is developed for elements with up to three fractal levels. The simulation was carried out using Ansoft Designer software. For results validation, several FSS prototypes with fractal elements were fabricated. In the fabrication process, fractals elements were designed using computer aided design (CAD) tools. The prototypes were measured using a network analyzer (N3250A model, Agilent Technologies). Matlab software was used to generate compare measured and simulated results. The use of fractal elements in the FSS structures showed that the use of high fractal levels can reduce the size of the elements, at the same time as decreases the bandwidth. We also investigated the effect produced by cascading FSS structures. The considered cascaded structures are composed of two FSSs separated by a dielectric layer, which distance is varied to determine the effect produced on the bandwidth of the coupled geometry. Particularly, two FSS structures were coupled through dielectric layers of air and fiberglass. For comparison of results, we designed, fabricated and measured several prototypes of FSS on isolated and coupled structures. Agreement was observed between simulated and measured results. It was also observed that the use of cascaded FSS structures increases the FSSs bandwidths and, in particular cases, the number of resonant frequencies, in the considered frequency range. In future works, we will investigate the effects of using different types of fractal elements, in isolated, multilayer and coupled FSS structures for applications on planar filters, high-gain microstrip antennas and microwave absorbers
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Kopecki, Ianina [Verfasser]. "Calculational approach to FST-hemispheres for multiparametrical benthos habitat modelling / von Ianina Kopecki." Stuttgart : Inst. für Wasserbau, 2008. http://d-nb.info/99679557X/34.
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Moura, Leidiane Carolina Martins de. "Caracteriza??o de FSS com Geometria Estrela de Quatro Bra?os Tipo Fenda." reponame:Repositório Institucional do IFPB, 2016. http://repositorio.ifpb.edu.br/jspui/handle/177683/261.
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Made available in DSpace on 2016-11-23T14:36:47Z (GMT). No. of bitstreams: 1 CARACTERIZA??O_DE_FSS_COM_GEOMETRIA_ESTRELA_DE_QUATRO_BRA?OS_TIPO_FENDA.pdf: 3334448 bytes, checksum: 72e9a0cc6327c3ea260649a17ee9e917 (MD5) Previous issue date: 2016-11-23
Nos ?ltimos anos, devido ao intenso crescimento de aplica??es que utilizam os sistemas de telecomunica??es, a demanda de disponibilidade de bandas de frequ?ncia do espectro eletromagn?tico tem se tornado cada vez maior. Embora esse crescimento seja determinado principalmente por tecnologias desenvolvidas para tablets e smartphones, o espectro eletromagn?tico ? ainda disputado por diversos servi?os, tais como os sistemas de posicionamento global, TV digital, servi?os de internet e outros. Diante disso, os engenheiros de telecomunica??es e micro-ondas buscam por novas tecnologias capazes de suprir as demandas espec?ficas desses dispositivos. Nesse contexto, uma das estruturas que tem recebido consider?vel aten??o de diversos grupos de pesquisa ? a superf?cie seletiva em frequ?ncia, FSS, pois pode desempenhar um papel fundamental na otimiza??o de sistemas de telecomunica??es, possibilitando, entre outras aplica??es, a redu??o de sinais indesej?veis e opera??o multibanda. A fim de se obter dimens?es reduzidas, resposta em frequ?ncia espec?fica e opera??o multibanda, diversas geometrias s?o estudadas, incluindo elementos simples ou uma combina??o dos mesmos, em que o elemento da c?lula unit?ria pode ser constitu?do a partir de uma camada de metaliza??o impressa sobre um substrato diel?trico, ou uma fenda em uma camada de metaliza??o sobre um substrato diel?trico. Logo, neste trabalho ? apresentada a an?lise da geometria estrela de quatro bra?os tipo fenda para FSS, destacando-se as suas caracter?sticas de redu??o de dimens?es e opera??o multibanda. O dimensionamento da estrutura, o ajuste da resposta em frequ?ncia e a sua reconfigura??o a partir da comuta??o s?o aspectos abordados. Para a an?lise num?rica das FSS s?o utilizados o M?todo das Ondas, mais conhecido na literatura como WCIP (Wave Concept Iterative Procedure), empregando o programa WCIPAG08?, desenvolvido no GTEMA-IFPB, e o M?todo dos Momentos, no qual se baseia o programa comercial ANSOFT-DESIGNER. Os resultados num?ricos e experimentais apresentaram boa concord?ncia entre si. Al?m disso, observa-se que o ajuste da resposta em frequ?ncia e a opera??o multibanda foram obtidos sem altera??o das dimens?es da c?lula unit?ria. S?o propostas equa??es aproximadas de projetos e apresentada a compara??o entre as caracteriza??es anal?tica, num?rica e experimental.
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OLIVEIRA, Manuelle Regina Tavares de. "Superfície Seletiva de Frequência Reconfigurável (RFSS) baseada em Dipolo Cruzado." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/25983.
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DISSERTAÇÃO Manuelle Regina Tavares de Oliveira.pdf: 2931763 bytes, checksum: 4765cfc2bda1f0392139117896216e71 (MD5)Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-08-29T17:40:49Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Manuelle Regina Tavares de Oliveira.pdf: 2931763 bytes, checksum: 4765cfc2bda1f0392139117896216e71 (MD5)
Made available in DSpace on 2018-08-29T17:40:49Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Manuelle Regina Tavares de Oliveira.pdf: 2931763 bytes, checksum: 4765cfc2bda1f0392139117896216e71 (MD5) Previous issue date: 2016-02-23
CAPES
Este trabalho apresenta o desenvolvimento, simulação e fabricação de duas Superfícies Seletivas em Frequências (FSS) baseadas no dipolo cruzado. A célula unitária da primeira estrutura é composta de um patch dipolo cruzado quando o diodo está no estado OFF, reversamente polarizado, e uma estrutura chamado hash quando o diodo está no estado ON, diretamente polarizado. O patch dipolo cruzado tem uma característica de filtro rejeita faixa, e o hash vai se comportar como um filtro passa faixa na frequência de interesse projetada. A segunda estrutura tem como célula unitária a abertura dipolo cruzado quando o diodo está no estado ON e patch quadrado quando o diodo está no estado OFF. Foram utilizadas fitas de cobre impressas no subestrato no lugar dos diodos para verificar o conceito de reconfigurabilidade. As respostas em frequência desses filtros foram analisadas segundo o método de circuito equivalente, e as simulações do software CST Studio Suite e resultados experimentais dos protótipos construídos foram usados para validar esses resultados.
This work present the development, simulation and manufacturing of two Frequency Selective Surfaces (FSS) using elements based on the cross dipole geometry. The unit cell of the first structure consists of a cross dipole patch when the diode is in the OFF state, reverse biased, and a hash when the diode is in the ON state, forward biased. The cross dipole patch has a stop-band filter characteristic, and the hash element will behave as a pass band filter response on the desired frequency range. The second unit cell structure is a cross dipole slot when the diode is ON state and a square patch when the diode is OFF state. Copper strips were used instead of the diodes to demonstrate the reconfigurable concept. The frequency responses of these filters were analyzed using the equivalent circuit method. The CST software simulation and experimental results of constructed prototypes were used to validate these results.
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Bozzi, Sandrine. "Optimisation du procédé FSSW (Friction Stir Spot Welding) pour des assemblages homogènes A1/A1 et hétérogènes A1/Acier." Paris 11, 2009. http://www.theses.fr/2009PA112314.
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Le Friction Stir Spot Welding (FSSW) est un procédé de soudage thermomécanique : un outil constitué d’un épaulement et d’un pion est mis en rotation rapide et pénètre dans les deux tôles superposées à assembler. La chaleur produite par le frottement de l’outil sur les tôles provoque un ramollissement de la matière. La rotation du pion permet alors de malaxer la matière des deux tôles. L’outil se retire ensuite en laissant une empreinte. Le FSSW permet ainsi le soudage de l’aluminium grâce à un malaxage entre les deux tôles. L’écoulement de la matière dans la zone de malaxage a pu être identifié. Il existe précisément deux flux distincts : des remontées externes de la matière et un malaxage interne le long de la paroi du pion. Il en résulte alors l’apparition de stries dans la zone de malaxage, qui correspondent à des films de matière fondue provenant du dessous du pion. D’un point de vue microstructurale, le mécanisme de recristallisation dynamique continue a été identifié, si bien que la zone de malaxage correspond à une zone de petits grains recristallisés d’environ 5µm de diamètre, entrecoupés de stries de grains plus fins d’environ 1µm, et de composition chimique différente. Quant aux propriétés mécaniques, elles sont fortement liées à l’écoulement de matière et à la microstructure qui en résulte, comme le montre notamment les mécanismes de rupture. La rupture à lieu par la propagation de la fissure située à l’extrémité de l’interface entre les deux tôles. Cette fissure se propage généralement en contournant la zone de malaxage qui présente une forte dureté due à l’affinement des grains, en empruntant le chemin marqué par le resserrement des stries. Ainsi, un moyen évident de retarder la rupture est donc d’obtenir une zone de malaxage la plus large possible. Mais il ne s’agit pas du seul facteur pour optimiser la tenue mécanique des points de soudure. L’inclinaison de la fissure à l’extrémité de l’interface est une autre donnée très influente. L’assemblage entre l’aluminium et l’acier, quant à lui, est rendu possible grâce à une accroche, c’est-à-dire à une remontée d’acier dans la tôle d’aluminium. Il y a alors formation de composés intermétalliques à l’interface entre l’accroche d’acier et l’aluminium grâce à un effet thermomécanique. Les précipités intermétalliques qui en résultent au niveau des accroches présentent une taille d’environ 250 nm et une dureté qui diffère fortement selon leur nature, allant jusqu’à 1100 HV. Ces zones intermétalliques deviennent alors des zones très fragiles qui peuvent détériorer le comportement mécanique des soudures. Lorsque ces précipités sont trop nombreux, et que leur microdureté est élevée, la rupture des points de soudure provient de nombreuses fissures qui apparaissent au niveau des zones intermétalliques. Mais ils restent nécessaires, car s’ils sont quasi inexistants, la tenue mécanique est très faible, la rupture ayant lieu par une rapide décohésion entre l’accroche d’acier et l’aluminium. Ainsi, pour une tenue mécanique optimale, une certaine quantité d’intermétalliques est nécessaire, ce qui correspond également à une surface d’accroche plus importante. Dans ce cas, l’accroche étant plus robuste, la rupture a lieu par déchirure de la tôle d’aluminium. L’ensemble des résultats a permis de montrer le fort potentiel du FSSW pour des applications homogènes de l’aluminium ainsi que pour des applications hétérogènes entre l’aluminium et l’acierFriction Stir Spot Welding (FSSW) is a thermomechanical joining process : a tool constituted by a retaining wall and by a pawn is put in fast rotation and penetrates into both sheet stacked to assembly. The heat produced by the friction of the tool on sheets provokes a softening of the material. The rotation of the pawn allows then to mix the material of both sheets. The tool withdraws then by leaving an imprit. Therefore the FSSW allows the joining of aluminium alloys thanks to a mixing between both sheets. The flow of the material in the stir zone was able to be indentified. There are exactly two different streams : external rises of material and an internal mix along the wall f the pawn. It results the appearance of streaks in the stir zone, which correspond to films of melted material resulting from the bottom of the pawn. From a microstructural point of view, the mechanism of dynamic continous recrystallisation was identified, so that the stir zone corresponds to a zone of small recristallized grains about 5 µm of diameter, interrupted of streak with finer grains about 1 µm, and of different chemical composition. As for the mechanical properties, they are strongly bound to the flow of material and to the microstructure which results from it, as shows it in particular the mechanism of break. The break take place by the distribution of the crack situated at the end of the interface between both sheets. This crack propagates generally by contourning the stir zone, which presents a strong hardness due to the refinement of grains, by taking the way marked by the contraction of sreak. S, an evident means to delay the break is to obtain the widest possible stir zone. But it is not about the only factor to optimize the mechanical strength. The slope of the crack a the end of the interface is another very influential datum. The assembly between aluminium and steel, as for its, is possible thanks to a hhok, that is to say an ascent of steel into the aluminium sheet. There is then formation of intermetallic compounds in the interface between the steel hook and the aluminium, thanks to a thermochemical effect. The intermetallic precipitates present a size about 250 nm, and a hardness which differs strongly according to their nature, until 1100 to HV. These intermetallic areas become the very fragile zones which can damage the welds mechanical behaviour. When these precipitates are on a too important quantity, and when their microhardness is raised, the hook rupture results from numerous cracks. But those intermetallic compounds remain necessary, because if they are almost non-existent, the mechanical strength is very weak : the fracture taking place by a fast separation between steel and aluminium. So, for an optimal mechanical strength, a certain quantity of intermetallic compounds is necessary, what also corresponds to a surface of sticks more important. In that case, hooks being more strong, the fracture takes place by a tear of the aluminium sheet. All the results allowed to show the strong potential of the FSSW for homogeneous applications of aluminium as well as for heterogeneous applications between aluminium and steel
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Aldabaldetreku, Rita, Juuso Lautiainen, and Alina Minkova. "The Role of Knowledge Management in Strategic Sustainable Development : Comparing Theory and Practice in Companies Applying the FSSD." Thesis, Blekinge Tekniska Högskola, Institutionen för strategisk hållbar utveckling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12360.
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The purpose of this study is to explore the role of knowledge management (KM) in integrating sustainability into business strategy in companies applying the framework for strategic sustainable development (FSSD).Corporations have the potential to be key players in moving society towards sustainability, but they lack clear definitions and guidelines around strategic sustainable development (SSD). The authors focus on the benefits of KM in organisations applying the FSSD, which offers general strategic guidelines, but does not refer to the complexity of managing the new sustainability knowledge.This study first examines the scientific literature around KM and FSSD and compares it with the results of expert interviews to develop a State of the Art Model of KM for SSD. Then the model is compared to current practices of corporations applying the FSSD and the gap is examined.The results of the analysis show that the concept of KM is widely discussed in the literature, yet it does not have much presence in the business world. The value of knowledge is recognised, but KM is not much used and no structured practices were identified. It was concluded that companies would benefit from a strategic KM system when integrating sustainability.
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Schulte, Jesko Pitt Manoel. "Smarta steg på väg mot hållbara transporter? : Snabbladdningsinfrastruktur och elvägar ur ett strategiskt livscykelperspektiv." Thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-46795.
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Transportsektorn står för en fjärdedel av Sveriges totala energianvändning och är orsaken till en tredjedel av de nationella utsläppen av växthusgaser. Samtidigt har regeringen satt upp högt ställda mål: fordonsflottan ska vara fossiloberoende år 2030 och Sverige ska inte ha några nettoutsläpp av växthusgaser år 2050. För att nå dit krävs det snabba och kraftfulla förändringar i transportsektorn. Elektrifiering har pekats ut som en nyckelfaktor för framgång. Men för att eldrivna fordon fullt ut ska kunna konkurrera och ersätta det fossildrivna systemet, krävs det satsningar på ny infrastruktur. Snabbladdare har redan börjat byggas på många håll, där eldrivna personbilar kan ladda sitt batteri på kort tid. Elvägar är ett samlingsnamn för innovativa tekniker där fordon, inklusive lastbilar, laddas med el från vägbanan medan de kör. Men vilken eller vilka tekniker är de mest strategiska stegen, språngbrädor, på väg mot en hållbar framtid och vad kännetecknar egentligen en sådan? Det här arbetet utgår ifrån ramverket för strategisk hållbar utveckling som kan användas för att planera mot hållbarhet i komplexa system. Dess kärna består av backcasting utifrån fyra grundläggande principer för hållbarhet. Studien använder en kombination av olika metoder för att undersöka snabbladdningsinfrastrukturens och elvägars miljöpåverkan och kostnader ur ett strategiskt livscykelperspektiv. Den kunskapen används sedan för att bygga modeller för hur utsläppen till miljön förändras per investerad krona, också beroende på hur den använda elen produceras. Resultaten visar på en stor potential för minskad miljöpåverkan för båda tekniker som dock i hög grad är beroende på elmixen. Arbetet har också visat att det är viktigt att inkludera själva infrastrukturens miljöpåverkan i livscykelanalyser då den kan spela en betydande roll. Slutligen kunde förtydligas att det i många fall inte är utsläppen av koldioxidekvivalenter som utgör den största miljöpåverkan. Därför appelleras till att utgå ifrån ett mer holistiskt perspektiv vid miljöpåverkansbedömningar. Det har även identifierats ett antal betydande faktorer som det fortfarande råder stor osäkerhet kring. Det rekommenderas därför att fylla kunskapsluckor och att utöka modellerna med både fler alternativ och fler faktorer för att få en mer detaljerad bild av vilken teknik som kan leda Sverige mot en hållbar framtid.The transport sector accounts for one fourth of Sweden’s total energy use and causes one third of the national emissions of greenhouse gases. At the same time, the Swedish government has set high goals: the vehicle fleet shall be fossil-independent until 2020 and Sweden shall not have any net emissions of greenhouse gases 2050. Quick and powerful actions are needed in order to reach these goals. Electrification has been pointed out as a key factor for success. In order for electric vehicles to be able to challenge and replace the fossil system, investment in new infrastructure is necessary. Fast chargers, where passenger cars can recharge their battery in short time, are already in place in many parts of Sweden. Electric roads is a term for new and innovative technologies where vehicles are charged from the road while they are driving. But which technique is the most strategic stepping stone on the way to sustainability? This study has its ground in the framework for strategic sustainable development which can be used to plan for sustainability in complex systems. At its core it uses backcasting from four basic sustainability principles. This work uses a combination of different methods to investigate the environmental impact and costs of fast charging infrastructure and electric roads from a strategic life cycle perspective. That information is then used to build models to take a closer look at how emissions to the environment change per invested Swedish crown, also dependent on how the used electricity is produced. The results show a large potential to decrease the environmental impact for both techniques, but it is strongly dependent on the electricity mix. Furthermore, this work shows that is is important to include the environmental impact of the infrastructure itself in life cycle analyses, because it can has a significant share in the total emissions. Finally, it is pointed out that it often not is the case that the emissions of carbon dioxide equivalents are the most important impact. It is therefore crucial to use a more holistic perspective in life cycle impact assessments. This work has identified a number of factors with large relevance but also large uncertainty. It is therefore recommended to fill the identified knowledge gaps and to expand the presented models with more factors and more alternative techniques, to get a more detailed picture of which solution is the best stepping stone on Sweden’s way to a sustainable future.
Greencharge Sydost
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LIMA, Isaac Silva Sousa. "CARACTERIZA??O DE FSS COM GEOMETRIA EM FORMA DE ESTRELA DE QUATRO BRA?OS." reponame:Repositório Institucional do IFPB, 2014. http://repositorio.ifpb.edu.br/jspui/handle/177683/238.
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Submitted by Alex Sandro R?go (alex@ifpb.edu.br) on 2016-09-01T13:10:13Z
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Made available in DSpace on 2016-09-01T13:10:38Z (GMT). No. of bitstreams: 1 CARACTERIZA??O DE FSS COM GEOMETRIA EM FORMA DE ESTRELA DE QUATRO BRA?OS.pdf: 17969955 bytes, checksum: a291b0138a771d13c9b2960bbc2cba98 (MD5) Previous issue date: 2014-07
O aumento da procura por dispositivos de comunica??o m?veis com capacidade de transmiss?o elevada e com dimens?es reduzidas, tem levado engenheiros de telecomunica??es e micro-ondas a realizarem trabalhos e pesquisas constantes na busca por novas tecnologias capazes de suprir essas demandas. T?cnicas de miniaturiza??o e emprego de sistemas de antenas inteligentes s?o algumas das alternativas mais comuns nesse processo. Recentemente, alguns grupos de pesquisa v?m estudando a efici?ncia das superf?cies seletivas em frequ?ncia (FSS) nesse tipo de sistema. Nesse contexto esse trabalho prop?e a apresentar uma nova geometria para fabrica??o de FSS. Definida como geometria estrela de quatro bra?os, a estrutura proposta apresenta caracter?sticas de miniaturiza??o e comuta??o. O documento apresenta o problema que motivou o desenvolvimento do projeto, assim como conceitos e defini??es sobre FSS, suas principais caracter?sticas, t?cnicas de an?lises e medi??es e aplica??es mais comuns. O texto traz ainda a formula??o te?rica do m?todo das ondas (WCIP) aplicado na an?lise de FSS. Esse m?todo num?rico tem a capacidade de determinar o comportamento da onda eletromagn?tica ao incidir sobre uma FSS e vem sendo estudado pelo GTEMA - IFPB como base te?rica do software desenvolvido pelo grupo, o WCIP08. A geometria estrela de quatro bra?os ? apresentada em sua forma sim?trica e assim?trica, e suas respectivas varia??es. Cada estrutura foi caracterizada numericamente, em seguida foram constru?dos prot?tipos para caracteriza??o experimental. Por fim os resultados foram comparados e constatou-se uma boa concord?ncia entre eles. Al?m disso, os testes confirmaram a efici?ncia da geometria em estudo para poss?veis aplica??es em sistemas de comunica??o que necessitem de
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Picolo, Miléia Ricci. "Grupamento de progênies obtidas de cruzamentos entre clones cerúleos de Cattleya walkeriana por meio de RAPD." Universidade do Oeste Paulista, 2008. http://bdtd.unoeste.br:8080/tede/handle/tede/373.
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Previous issue date: 2008-12-01Cattleya walkeriana is widely grown by collectors and receive special attention by the breeders because it exhibit a rare colour variation and a great visual effect. RAPD markers (Random Amplified Polymorphic DNA) are one of the molecular markers most used in genetic studies. They have advantages, such as low amount of genomic DNA, hybridization absence, gene amplification at low costs and easy implementation. The DNA extracted from Cattleya walkeriana plants, wild and from cerulean offsprings, was amplified by elected RAPD primers. With the generated bands it was possible to estimate the fixation allelic index (FST) and to construct a dendogram. It could be inferred that Cattleya walkeriana is an allogamous species and that was a decrease in the genetic variability among the crosses as the recessive plants were used. Cerulean plants are difficult to obtain since they have all the pairs of genes in the recessive form. The inheritance for the trait in question is oligogenic and determined by genes that act in a complementary manner and are segregated independently.
Cattleya walkeriana é amplamente cultivada por colecionadores e tem recebido especial atenção dos melhoristas por apresentar variações na forma da coloração que são raras de serem obtidas, e possuem grande valor visual. Marcadores RAPD (polimorfismo de DNA amplificado ao acaso) são um dos tipos de marcadores moleculares mais utilizados em estudos genéticos por apresentarem vantagens como a utilização de baixa quantidade de DNA genômico, ausência de hibridação, emprego de amplificação gênica além de baixo custo e fácil execução. Para a realização deste trabalho, foi extraído DNA de diversas plantas de Cattleya walkeriana, plantas nativas e de progênies, obtidas de outras plantas de forma cerúlea, cujo DNA foi amplificado por marcadores RAPD selecionados. A partir das bandas geradas foi possível estimar o índice de fixação alélica (FST) e construir um dendrograma das amostras. Determinou-se que Cattleya walkeriana é uma espécie alógama e que houve diminuição da variabilidade genética dentro dos cruzamentos á medida que plantas recessivas de mesmo fenótipo foram utilizadas. Plantas cerúleas são de difícil obtenção, pois apresentam todos os pares de genes na forma recessiva. A herança para a característica em questão é oligogênica e determinada por genes que atuam de maneira complementar e são de segregação independente.
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Edblad, Isak, and Charlotta Johansson. "Public service och tvåspråkigheten : en studie av tablåutvecklingen i Finlands Svenska Television (FST) 1986-2011." Thesis, Södertörns högskola, Institutionen för kommunikation, medier och it, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-15832.
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Det politiska uppdraget för Public Service Broadcasting (PSB) i Finland är att bedriva programverksamhet som erbjuder ett mångsidigt utbud av fakta, åsikter och diskussion samt utveckla inhemsk konst, kultur och stimulerande underhållning. Yle ska behandla den finskspråkiga och den svenskspråkiga befolkningen på lika grunder. Under många år samsände Yles svenska och finska verksamhet. Först 2001 fick de svenskspråkiga programmen en egen kanal, FST5 och från den 1 september 2011 delar Sveriges Televisions utlandskanal SVT World kanalplats med FST5. Uppsatsens syfte är att undersöka hur det svenskspråkiga programutbudet i Yle utvecklats mellan 1986 och 2011 med utgångspunkt från public serviceuppdraget. Undersökningen utgörs av en kvantitativ studie av programtablån under en vecka åren 1986, 1996 och 2006 och två veckor året 2011, före och efter samsändningen med SVT World. Ur det längre perspektivet visar resultatet att programtiden ökat starkt, men samtidigt att repriser har ökat och att aktualitetsprogram har minskat. Program från Norden har också blivit fler. Sett ur ett kortare perspektiv har man under 2011 minskat den egna sändningstiden samtidigt som programtyper som nyheter, ekonomi och väder och underhållning och kultur kompenserats av SVT Worlds sändningar. Detta kan ses som en konsekvens av sparkrav som verksamheten ställts inför, men sett ur ett längre perspektiv har ändå programutbudet breddats. Nyhetsprogram har dock knappt ökat under den undersökta perioden. I det stora hela har Yle levt upp till det politiska public serviceuppdraget.
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Kohlgraf, Dana C. "Design and testing of a frequency selective surface (FSS) based wide-band multiple antenna system." Connect to this title online, 2005. http://hdl.handle.net/1811/323.
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Thesis (Honors)--Ohio State University, 2005.Title from first page of PDF file. Document formattted into pages: contains ix, 54 p.; also includes graphics. Includes bibliographical references (p. 54). Available online via Ohio State University's Knowledge Bank.
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Yeoh, Terence Eng Siong. "Validation Of The Facet Satisfaction Scale (Fss): An Evaluative Approach To Assessing Facet Job Satisfaction." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103414/.
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Job satisfaction has, and continues to be an important construct of interest to researchers and practitioners alike. However, conflicting operational definitions and inconsistent measurement systems have reduced the efficacy of the construct in predicting important job-related outcomes for organizations and their employees. The Facet Satisfaction Scale (FSS) was designed to overcome these deficiencies by creating a facet-based measure that assesses job satisfaction in accordance with recent definitions of the construct. Reliability and validity analyses were conducted on both the complete and shortened version of the scale. The FSS exhibited evidence of reliability (ranging from .52 to .93 for the shortened FSS, and .53 to .96 for the complete FSS). Evidence of scale validity was also obtained through the use of construct, content, and criterion-related validity measures. Implications of the study on future research on job satisfaction are discussed.
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Archer, Isaiah, Lewis Muirhead, and Sarah Forrester-Wilson. "Exploring Holacracy’s Influence on Social Sustainability Through the Lens of Adaptive Capacity." Thesis, Blekinge Tekniska Högskola, Institutionen för strategisk hållbar utveckling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12656.
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The organizational structure of Holacracy has been gaining popularity in recent years, but a lack of academic research on Holacracy called for a systematic approach to assessing its merits and shortcomings. The need Holacracy fills, is that of organizations dealing with a complex world and rapidly evolving technology. While Holacracy is not tailored to address sustainability issues, there are many components that made it a candidate for the researchers to examine it through a social sustainability lens. This study examines the effect of specific components of Holacracy with elements of adaptive capacity – a theory from which the research definition of social sustainability was built. With the goal of determining the effect of Holacracy on social sustainability, a questionnaire directed at employees and practitioners of holacratic organizations was utilized. The findings implied that Holacracy does positively influence the experience of the elements of adaptive capacity; with the relationship to the adaptive capacity element of self-organization being a standout. The importance of trust is also identified. The link to the Framework for Strategic Sustainable Development can be elucidated through adaptive capacity’s influence to the social sustainability principles. Because of the importance of social sustainability and social capital to organizational performance and longevity, this research is of value to any business using, or considering using Holacracy.
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Sandilya, Hrishabh. "Analysing Laudato si': On Care for Our Common Home, from the Perspective of the Framework for Strategic Sustainable Development (FSSD)." Thesis, Uppsala universitet, Teologiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-419506.
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Souza, Adriano Gouveia de. "An?lise espectral de reflectarrays com substratos de duas camadas diel?tricas anisotr?picas uniaxiais." Universidade Federal do Rio Grande do Norte, 2006. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15393.
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Previous issue date: 2006-06-12Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
Recently, an amazing development has been observed in telecommunication systems. Two good examples of this development are observed in mobile communication and aerospace systems. This impressive development is related to the increasing need for receiving and transmitting communication signals. Particularly, this development has required the study of new antennas and filters. This work presents a fullwave analysis of reflectarrays. The considered structures are composed by arrays of rectangular conducting patches printed on multilayer dieletric substrates, that are mounted on a ground plane. The analysis is developed in the spectral domain, using an equivalent transmission line method in combination with Galerkin method. Results for the reflection coefficient of these structures are presented and compared to those available in the literature. A good agreement was observed. Particularly, the developed analysis uses the transmission lines theory in combination with the incident potentials and the field continuity equations, at the structures interfaces, for obtaining the scattered field components expressions as function of the patch surface currents and of the incident field. Galerkin method is used to determine the unknown coefficients in the boundary value problem. Curves for the reflection coefficient of several reflectarray geometries are presented as function of frequency and of the structural parameters
Os constantes avan?os das telecomunica??es tornam-se cada vez mais evidentes nas ?ltimas d?cadas. As tecnologias de comunica??es m?veis e da ind?stria aeroespacial s?o um bom exemplo desta evolu??o. Isto ocorreu devido ao aumento do fluxo de dados a serem transmitidos. Para suprir essa demanda, novas tecnologias v?m surgindo na constru??o de antenas e na filtragem dos sinais de RF. Este trabalho apresenta uma an?lise de onda completa de estrutura de arranjos refletores (reflectarray). A estrutura analisada ? composta por um arranjo de patches condutores retangulares depositados sobre um substrato com duas camadas de materiais iso/anisotr?picos, que por sua vez est?o montadas sobre um plano de terra. A an?lise foi efetuada no dom?nio espectral, sendo utilizado o m?todo da linha de transmiss?o equivalente em combina??o com o m?todo de Galerkin. Como resultado foram obtidos os coeficientes de reflex?o (amplitude e fase) correspondentes para as estruturas analisadas. Para valida??o desses resultados foi realizada uma compara??o com os resultados dispon?veis na literatura. Especificamente, a an?lise desenvolvida usa a teoria de linha de transmiss?o em conjunto com os potenciais incidentes e com a imposi??o da continuidade dos campos nas interfaces de contorno, para a obten??o das express?es das componentes dos campos espalhados em fun??o das densidades de corrente do patch e dos campos incidentes. O m?todo de Galerkin ? utilizado na determina??o num?rica dos coeficientes pesos desconhecidos. Desta forma, s?o determinados os coeficientes de reflex?o (amplitude e fase) das estruturas consideradas
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Souza, Adriano Gouveia de. "An?lise espectral de reflectarrays com substrato de duas camadas diel?tricas anisotr?picas uniaxiais." Universidade Federal do Rio Grande do Norte, 2006. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15514.
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Recently, an amazing development has been observed in telecommunication systems. Two good examples of this development are observed in mobile communication and aerospace systems. This impressive development is related to the increasing need for receiving and transmitting communication signals. Particularly, this development has required the study of new antennas and filters. This work presents a fullwave analysis of reflectarrays. The considered structures are composed by arrays of rectangular conducting patches printed on multilayer dieletric substrates, that are mounted on a ground plane. The analysis is developed in the spectral domain, using an equivalent transmission line method in combination with Galerkin method. Results for the reflection coefficient of these structures are presented and compared to those available in the literature. A good agreement was observed. Particularly, the developed analysis uses the transmission lines theory in combination with the incident potentials and the field continuity equations, at the structures interfaces, for obtaining the scattered field components expressions as function of the patch surface currents and of the incident field. Galerkin method is used to determine the unknown coefficients in the boundary value problem. Curves for the reflection coefficient of several reflectarray geometries are presented as function of frequency and of the structural parameters
Os constantes avan?os das telecomunica??es tornamse cada vez mais evidentes nas ?ltimas d?cadas. As tecnologias de comunica??es m?veis e da ind?stria aeroespacial s?o um bom exemplo desta evolu??o. Isto ocorreu devido ao aumento do fluxo de dados a serem transmitidos. Para suprir essa demanda, novas tecnologias v?m surgindo na constru??o de antenas e na filtragem dos sinais de RF. Este trabalho apresenta uma an?lise de onda completa de estrutura de arranjos refletores (reflectarray). A estrutura analisada ? composta por um arranjo de patches condutores retangulares depositados sobre um substrato com duas camadas de materiais iso/anisotr?picos, que por sua vez est?o montadas sobre um plano de terra. A an?lise foi efetuada no dom?nio espectral, sendo utilizado o m?todo da linha de transmiss?o equivalente em combina??o com o m?todo de Galerkin. Como resultado foram obtidos os coeficientes de reflex?o (amplitude e fase) correspondentes para as estruturas analisadas. Para valida??o desses resultados foi realizada uma compara??o com os resultados dispon?veis na literatura. Especificamente, a an?lise desenvolvida usa a teoria de linha de transmiss?o em conjunto com os potenciais incidentes e com a imposi??o da continuidade dos campos nas interfaces de contorno, para a obten??o das express?es das componentes dos campos espalhados em fun??o das densidades de corrente do patch e dos campos incidentes. O m?todo de Galerkin ? utilizado na determina??o num?rica dos coeficientes pesos desconhecidos. Desta forma, s?o determinados os coeficientes de reflex?o (amplitude e fase) das estruturas consideradas
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Machio, Nyongesa. "Influence of composition and thermomechanical processing on microstructure evolution in AISI 430 ferritic stainless steel(FSS)." Master's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/17931.
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Bibliography: p. 100-106.This thesis examines the influence of austenite potential and hot roll finish temperature on the evolution of microstructure in the ferritic stainless steel grade AISI 430. In particular, it focuses on the influence of these variables on the hot band annealing behaviour of this steel. The material employed was obtained from laboratory and commercial heats. Two hot roll finish temperatures, viz. 600°C and 800°C for the commercial heats and two alloy compositions of austenite potential 11 and 61% for the laboratory heats were studied. Electron channelling contrast (ECC) obtained in scanning electron microscopy was used to follow the evolution of microstructure. Limited micro texture measurements were made using electron backscattered techniques. It was found that a low finish temperature produced a hot rolled microstructure that showed limited softening and a fully recrystallised microstructure after annealing while a high hot roll finish temperature produced a completely softened as-hot-rolled microstructure and only partial recrystallisation after annealing. A high austenite potential encouraged the ferrite phase to undergo extensive continuous recrystallisation during hot band annealing. However, the affinity for the precipitation of carbo-nitrides tended to play a role in slowing down the process. On the other hand, the ferrite phase deformed in the presence of a low austenite content mostly underwent extended recovery during hot band annealing. The softening here was affected by a low driving force. The end microstructures after annealing were however similar in both cases in as much as they consisted of elongated structures. The martensite phase was found to behave similarly regardless of the austenite content, where both recovery to produce subgrains and occasional recrystallisation occurred. During final recrystallisation after cold rolling, the high austenite potential coupled with a short hot band anneal time resulted in incomplete recrystallisation. This caused sharper alpha fibre texture components in the final sheet. A long hot band anneal time however resulted in sharper gamma-fibre texture components. In the case of low austenite potential, a long hot band anneal produced a random texture in the final texture. Ridging was observed in all cases but a high austenite content was found to lessen its severity. Also, it (ridging) was reduced by the random texture produced by long hot band annealing in the case where the austenite potential was low.
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Jacob, Fredriksson. "Framgångsfaktorer för effektiv och säker vägtrafikledning : Utveckling av utvärderingsverktyget FST för Trafikverkets operativa ledningscentraler för vägtrafik." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119641.
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Hela samhället tjänar på en säker och lättframkomlig trafik både ur ett samhällsekonomisk och individuellt perspektiv. Trafikverkets trafikledningscentraler arbetar aktivt för att se till att alla som vistas på vägarna gör så på ett så säkert sätt som möjligt. Studien har konstaterat att det finns ett växande behov av att kunna utvärdera trafikledningens funktionalitet därav har ett utvärderingsverktyg utvecklats. Empiriskt material har införskaffats genom observationsintervjuer på Trafikverkets trafikledningscentraler för vägtrafik, totalt införskaffades 42 timmar observationsintervjuer över 6 dagar. Genom en kvalitativ tematisk analys har framgångsfaktorer eller teman identifierats för effektiv och funktionell trafikledning. Dessa faktorer, bland annat kontroll, verifiering och kommunikation ligger som grund för det utvärderingsverktyg som tagits fram. En första analys av systemet utfördes med hjälp av Nielsens heuristiker för att kartlägga behovet av gränssnittsstudier. I materialet visade det sig att de största utmaningarna låg på en högre nivå och en bredare analys av trafikledningen krävdes för att skapa ett mer användbart verktyg. Möjligheterna till att skapa en god situationsmedvetenhet visade sig vara nära kopplat till systemets övergripande funktionalitet vilket bidrog till studiens inriktning och resultat. Resultatet av den kvalitativa analys som utförts över systemet ligger som grund för det utvärderingsverktyg som skapats. Förhoppningen är att verktyget kan bidra med att vidareutveckla och utvärdera dagens vägtrafikledning. Resultatet i studien belyser även vikten av att kontrollera för flertalet olika faktorer inom vägtrafikledning när en trafikledningscentrals funktionalitet kartläggs.
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Ara?jo, Lincoln Machado de. "Caracteriza??o de superf?cies seletivas de frequ?ncia de peri?dicas e n?o-peri?dicas." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br/handle/123456789/20095.
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Os ?ltimos anos foram marcados por um grande interesse no uso de superf?cies seletivas de frequ?ncia (FSS), como filtros espaciais, em diversas aplica??es em microondas. Dentre estas, destacam-se as aplica??es em sistemas de telecomunica??es (tais como: comunica??es por sat?lite e radar), antenas de ganho elevado (em estruturas combinadas com antenas planares) e fornos de micro-ondas (dom?sticos e industriais). As FSS s?o geralmente compostas por arranjos peri?dicos bidimensionais, com elementos igualmente espa?ados, que podem ser patches met?licos (impressos em substratos diel?tricos) ou aberturas (perfuradas em superf?cies met?licas finas). Nestas configura??es (de arranjos peri?dicos), as FSS v?m conseguindo atender ?s demandas da ind?stria de telecomunica??es de maneira satisfat?ria. Entretanto, novas demandas v?m encontrando limita??es na tecnologia empregada. Neste contexto, requisitos de filtragem adversos v?m for?ando os projetistas de FSS a utilizarem m?todos de otimiza??o na tentativa de encontrar formatos espec?ficos para seus elementos, por exemplo. Outra alternativa que vem sendo utilizada para aumentar a seletividade das FSS ? o cascateamento, uma t?cnica simples que tem como principal ponto negativo o aumento das dimens?es da estrutura, assim como do seu peso. Este trabalho prop?e o desenvolvimento de uma nova classe de superf?cies seletivas de frequ?ncia (FSS), constitu?das de arranjos quase-peri?dicos (ou n?o-peri?dicos). Resultados de superf?cies seletivas de frequ?ncia n?o-peri?dicas e flex?veis tamb?m ser?o apresentados, mostrando uma nova gama de aplica??es. Portanto, as FSS propostas n?o apresentam periodicidade em rela??o ? posi??o espacial dos seus elementos. As respostas em frequ?ncia destas estruturas foram simuladas utilizando softwares comerciais que implementam m?todos de onda completa. Para valida??o do estudo efetuado, foram constru?dos e medidos prot?tipos das FSS propostas, tendo sido observada uma boa concord?ncia entre os resultados simulados e medidos. S?o apresentadas e comentadas as principais conclus?es deste estudo, al?m de indicadas sugest?es para a sua continuidade.
The past years have seen a great interest in the use of frequency selective surfaces (FSS), as spatial filters, in many microwave applications. Among these, we highlight applications in telecommunication systems (such as satellite communications and radar), high gain antennas (combined with planar antennas) and (home and industrial) microwave ovens. The FSS is usually composed of two-dimensional periodic arrays, with equally spaced elements, which may be metallic patches (printed on dielectric substrates) or aperture (holes in thin metal surfaces). Using periodic arrays, the FSS have been able to meet the demands of the telecommunications industry. However, new demands are finding technological limitations. In this context, adverse filtering requirements have forced designers to use FSS optimization methods to find specific formats of FSS elements. Another alternative that has been used to increase the selectivity of the FSS is the cascaded FSS, a simple technique that has as main drawback the increased dimensions of the structure, as well as its weight. This work proposes the development of a new class of selective surfaces frequency (FSS) composed of quasi-periodic (or non-periodic) arrangements. The proposed FSS have no array periodicity, in relation with the spatial position of their elements. The frequency responses of these structures were simulated using commercial softwares that implement full-wave methods. For the purpose of validation of this study, FSS prototypes were built and measured, being possible to observe a good agreement between simulated and measured results. The main conclusions of this work are presented, as well as suggestions for future works.
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Crain, Tori Laurelle. "The Crossover Effects of Supervisor Work-Family Positive Spillover on Employee Sleep Deficiency: Moderating Effects of Family Supportive Supervisor Behaviors (FSSB)." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/895.
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The majority of literature on the work-family interface has focused on, and provided evidence of, the conflict associated with engagement in both work and family roles (Eby, Casper, Lockwood, Bordeaux, & Brinley, 2005). Research examining the positive aspects of work and family participation remains limited. The current study investigated how work-family positive spillover is transferred between members of the supervisor-employee dyad and subsequently how this affects employee sleep outcomes. It was hypothesized that work-to-family affective positive spillover experienced by supervisors would crossover to employees and increase their experiences of work-to-family affective positive spillover. In turn, this would allow for better employee sleep. It was also proposed that these relationships would depend on the level of employee perceptions of family-supportive supervisor behaviors (FSSB), such that higher levels of FSSB would result in higher levels of employee positive spillover and better employee sleep. As part of a larger study, survey data were collected in a sample of 696 workers supervised by 180 managers in the information technology sector. Contrary to expectations, results indicated that supervisor positive spillover was negatively related to employee positive spillover. Furthermore, FSSB moderated the association between supervisor positive spillover and employee sleep duration, such that the relationship between supervisor positive spillover and employee sleep duration was positive under high levels of FSSB, but negative under low levels of FSSB. Again, this finding was contrary to expectations. Alternative explanations are discussed.
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Smith, Justin L. "New sharing method between the Fixed Satellite Service and the Aeronautical Mobile Satellite Service in the 14.0-14.5 GHz band." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31049.
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In the US, the 14.0-14.5 GHz band is allocated on a primary basis to the Radio-Navigation and the FSS with a secondary allocation to the LMSS. The Radio-Navigation service is the use of RADAR for navigation. An example of Radio-Navigation is the ground proximity radar used for airplane collision avoidance. FSS stands for the Fixed Satellite Service. In general, an FSS is a satellite network consisting of a geo-stationary satellite and non-movable earth stations on the ground. An example of an FSS is the earth terminals used at gas stations to verify credit cards and centrally track inventory. The 14.0-14.5 GHz band is also allocated on a secondary basis to the LMSS or Land Mobile Satellite Service. This is a satellite network with a satellite and a movable terrestrial non-aeronautical earth station. An example of an LMSS is a system called Omnitracs, which provides a satellite-based data connection for the trucking industry. AMSS stands for the Aeronautical Mobile Satellite Service. An AMSS is an LMSS dedicated only to airplanes.
The CPM or Conference Preparatory Meeting after WRC or World Radio Conference-2000 decided there was an urgent need for technical and regulatory studies covering sharing between the FSS and the AMSS. The requirement for a report on the studies was added to the WRC-2003 agenda. The WRC also stipulated that the studies must demonstrate that sharing between the FSS and the AMSS is feasible enough to allocate AMSS a secondary status in the band. The studies need to be completed before WRC-2003. AMSS contends that sharing is feasible if their service can meet the same PFD limits of the LMSS. Presently, the FCC has licensed the AMSS on an experimental non-interference basis.
The FSS contends that characteristics are needed of the AMSS system and a detailed sharing study be completed to verify sharing is feasible. The FSS believes that sharing may not be feasible if the same transponder is used for AMSS and FSS. The FSS perceives that the AMSS is asking for a super secondary status. Super secondary status implies that the AMSS would only be required to adhere to PFD limits on individual aircraft and not for multiple aircraft in view of a victim FSS receiver. Future studies will clarify this issue.
The issues associated with the sharing analysis are; the modeling of the orbital separation of the satellites, the atmospheric interference into the communication link and the availability of the communication link between the FSS and the AMSS.
The issues associated with modeling of the simulation are the static, verses dynamic modeling environments and developing a dynamic software tool to track airplane movement. This thesis plans to propose a new sharing methodology between the FSS and the AMSS that could be contributed to the WRC-2003 agenda.
Three systems examples were provided at ITU meetings inresponse to the WRC-2003 agenda item. The three systems will abide by the ITU-R S.728 EIRP limits. The three systems indicate that static analysis shows that sharing is feasible involving only one aircraft as the interfere. This is not a reasonable solution for a real time environment because there is only one aircraft used. It is necessary for the link to support multiple aircraft.
The factors that indicate sharing is feasible are: non-harmful interference to the victim and reasonable enough link margin in the interfere system to make it viable. A viable system in the case of aircraft would include high-speed internet and video. The AMSS interfere system cannot propose a power limit that will not allow it to close itâ s own link.
In order to mitigate the interference, systems can agree to certain interference mitigation techniques. The different techniques are: transmitting power control, geostationary arc avoidance angle and orbital arc separation.
Power control as described above is the centralized control of the interfering antenna into the victim. This is done by simulating the interference environment and pre-scheduling the decreases of the transmitting power. This is a feasible solution except that it decreases the availability and thru-put of the interfere system. This approach can make the system have unrealistic link margins and spotty availability due to the pre-scheduled power control.
Another technique is the geostationary arc avoidance angle. This technique is not applicable since both the AMSS and FSS use geostationary orbits.
The third technique is geostationary separation. This technique requires co-channel systems to maintain a certain orbital spacing between them. FSS systems in certain bands have a minimum of 3 degrees of orbital spacing between co-channel systems. Since the AMSS has 01/25/03 a mobile terrestrial system (aircraft) as part of the link, it requires a higher orbital separation between it and the FSS system. The results of dynamic analysis indicate that this technique is feasible at 10 degree orbital spacing.
The Monte Carlo analysis completed for this thesis simulated the results of four scenarios: co-located, 3 degree, and 5 and 10-degree orbital separation. It can be determined from the results that the interference decreases as the orbital separation increases. These simulations were done based on a 10 aircraft interfere scenario.Master of Science
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Montezuma, Karina. "Efeito de antagonistas do receptor NMDA sobre a metilação do DNA." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/60/60138/tde-24102016-163014/.
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A depressão é uma doença com alta incidência na população mundial e os antidepressivos atualmente disponíveis não são completamente eficazes. Esses fármacos apresentam uma latência de 2-4 semanas para induzir uma melhora significativa dos sintomas e cerca de 45% dos pacientes não respondem ao tratamento, cujo mecanismo é baseado na facilitação da neurotransmissão monoaminérgica no SNC. Por outro lado, recentemente tem sido demonstrado que a ketamina, antagonista do receptor de glutamato do tipo NMDA induz um efeito antidepressivo rápido e sustentado em animais e pacientes. No entanto, o uso dessa droga para o tratamento da depressão possui diversas limitações e, assim, o entendimento dos mecanismos subjacentes à sua ação antidepressiva pode contribuir para o desenvolvimento de novas e melhores alternativas terapêuticas. Estes mecanismos parecem ser mais complicados do que simplesmente o bloqueio do receptor NMDA, dado que tal bloqueio com o antagonista MK-801, por exemplo, induz efeito tipo-antidepressivo no teste do nado forçado (FST) por até 3 horas, mas sem reproduzir os efeitos prolongados da ketamina. Por isso, a cascata de eventos neuroquímicos iniciada após a administração de ketamina que culmina com a regulação da expressão gênica e síntese de proteínas relacionadas aos processos de plasticidade neural têm sido alvo de grande investigação a fim de se compreender o mecanismo de ação subjacente ao efeito antidepressivo rápido e sustentado dessa droga. A expressão desses genes pode ser modulada por mecanismos epigenéticos, como a metilação do DNA, um processo realizado por DNA metiltransferases (DNMTs), que também tem apresentado grande relevância para a neurobiologia da depressão. Diante disso, o presente estudo teve como objetivo avaliar os efeitos da administração de antagonistas do receptor NMDA, ketamina e MK-801, em doses e protocolos de tratamento que promovam efeito tipo-antidepressivo no FST, sobre a metilação do DNA em estruturas encefálicas importantes para a neurobiologia da depressão, em animais submetidos ou não ao estresse de nado forçado. Para tanto, primeiramente, foram delineados protocolos experimentais para análise do efeito tipo-antidepressivo destas drogas: Em ratos, administração sistêmica aguda de S(+)-ketamina 10 mg/Kg ou MK-801 0,025 mg/Kg 23 horas após a sessão pré-teste e 1 hora ou 7 dias antes da sessão teste do FST, permitiu a análise de um efeito tipo-antidepressivo rápido e sustentado induzido pela ketamina e apenas rápido pelo MK-801. Em seguida, utilizando estes protocolos, avaliou-se os efeitos do estresse do pré-teste do FST e do tratamento com tais antagonistas do receptor NMDA sobre os níveis de metilação global do DNA e expressão de DNMT3a e DNMT3b no córtex frontal, hipocampo ventral e dorsal dos animais. Foram encontradas alterações nas quantificações realizadas, sugerindo que o estresse e o tratamento podem induzir efeitos importantes sobre a metilação do DNA nas estruturas analisadas. Além disso, o tratamento com ketamina ou MK-801 parecem induzir efeitos diferenciais em algumas regiões, o que poderia estar associado aos efeitos também distintos que apresentam sobre a ação antidepressivaAlthough depression presents a high incidence in the world population, currently available antidepressants exhibit a latency of 2-4 weeks to induce a significant improvement of symptoms and around 45% of patients do not respond to these drugs. On the other hand, it has been recently shown that ketamine, a NMDA receptor antagonist, induces a rapid and sustained antidepressant effect in animals and patients. However, the use of this drug for depression treatment has several limitations and, thus, the understanding of the mechanisms underlying its antidepressant action could present a significant importance for the development of new and better therapeutic alternatives. These mechanisms appear to be more complex than the initial blockade of the NMDA receptor, since such blockade by MK-801, for example, reduces the immobility time of mice submitted the forced swimming test (FST) for up to 3 hours, without reproducing the sustained effects of ketamine. Therefore, the cascade of neurochemical events that are initiated after ketamine administration that culminate in the regulation of gene expression and syntehsis of proteins related to neuronal plasticity has been the focus of intense investigation. These genes, in turn, can be modulated by epigenetic mechanisms such as DNA methylation, a process performed by DNA methyltransferase (DNMTs), which has also shown a high relevance to the neurobiology of depression and its treatment. Based on that, the present study aimed at investigating the effects induced by ketamine and MK-801, at doses and treatment protocols that promote antidepressant-like effect in the FST, upon DNA methylation in brain structures of animals submitted or not to the forced swim stress. The first experimental protocols were designed for the analysis of acute and sustained drug-induced antidepressant-like effects: In rats, acute systemic administration of S(+)-Ketamine 10 mg/Kg or MK-801 0.025 mg/Kg 23 hours after the pretest session and 1 hour or 7 days before the test session of FST was investigated. Based on these protocols, the effects of stress (FST) and of treatment with NMDA receptor antagonists were investigated on global DNA methylation levels and DNMT3a and Dnmt3b expression in the rat frontal cortex, ventral and dorsal hippocampus. Both, stress and treatment, induced changes in DNA methylation and DNMT3 expression in some of the brain regions analised. In addition, treatment with MK-801 and ketamine seem to induce differential effects in some areas, which could also be associated with different effects that they present on antidepressant action.
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Meier, David Duane. "Perceived Dangerousness of the Job and Well-Being Among Correctional Officers: the Role of Perceived Stress and Family Supportive Supervisor Behaviors (FSSB)." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1032.
Full textAbstract:
Occupational stress has become a world-wide epidemic exacting severe tolls on both businesses and employees alike. Of all the workplace stressors, the perceived dangerousness of one's job is ever present within the occupation of corrections. The current study examined the mediating process of perceived stress on the relationship between perceived dangerousness of the job and the negative employee well-being outcomes of work-family conflict and symptoms of psychological distress, as well as the moderating effects of family supportive supervisor behaviors on this process. As part of a larger study, survey data were collected from 1,370 state correctional officers. It was hypothesized that perceived stress would fully mediate the relationship between perceived dangerousness of job and the negative well-being outcomes and that family supportive supervisor behaviors would moderate this mediation such that increased levels of family supportive supervisor behaviors would mitigate the negative well-being outcomes. The mediation hypotheses were not found to be supported. However, family supportive supervisor behaviors were found to moderate the relationship between perceived dangerousness of the job and work-to-family conflict. Additionally, family supportive supervisor behaviors were found to moderate the relationship between perceived stress and physical symptoms of psychological distress.
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Matos, Suzana Ferreira de. "Referenciais de segurança dos alimentos : estudo comparativo entre ISO 22000 e FSSC 22000 quando aplicado a uma unidade de processamento de carne." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2020. http://hdl.handle.net/10400.5/20191.
Full textAbstract:
Dissertação de Mestrado Integrado em Medicina VeterináriaA crescente preocupação e exigência dos consumidores relativamente à segurança dos alimentos que lhes são fornecidos, leva à necessidade de todos os intervenientes da cadeia alimentar melhorarem a implementação de normas de segurança e qualidade e reforçarem todos os sistemas de gestão e controlo, desde a produção primária até ao consumidor final. O presente trabalho teve como objetivo principal, a implementação de um referencial de segurança dos alimentos, FSSC 22000, numa unidade de processamento de carnes de forma a comprovar a sua aptidão para fornecer produtos seguros, cumprindo os requisitos legais e acompanhando as exigências de um mercado cada vez mais competitivo e exigente. Como resultado do trabalho realizado ao longo do estágio, foram atualizados alguns documentos já pré-existentes, no âmbito da implementação da NP EN ISO 22000:2005, nomeadamente os fluxogramas de processo, a descrição das etapas e medidas de controlo, revisão da análise de potenciais perigos com nova categorização das medidas de controlo, revisão do Programa de Pré-Requisitos Operacionais, revisão do Plano HACCP e por fim validação, verificação e melhoria do Sistema de Gestão de Segurança Alimentar, nomeadamente das medidas de controlo de forma a estar conforme os requisitos da norma FSSC 22000. Foi igualmente elaborado um estudo comparativo entre o referencial NP EN ISO 22000:2005 e FSSC 22000 no qual foi verificado uma divergência nos requisitos exigidos e na estrutura dos referenciais. De forma a colmatar esta divergência foram aplicados esforços para cumprir com os requisitos exigidos o que levou à criação de novas etapas de processo nas diferentes etapas de produção, novos tipos de potenciais perigos identificados e por fim respetivas medidas preventivas. Verificou-se que com o esforço e empenho de todos os operadores, a unidade de processamento possuía todas as capacidades para implementar com sucesso, o referencial de segurança dos alimentos em questão.
ABSTRACT - Food Safety Standards: Comparative study between ISO 22000 and FSSC 22000 when applied to a meat processing unit - The growing concern and demand from consumers regarding the safety of the food supplied to them, leads to the need of all stakeholders of the food chain to improve quality standards implementation and reinforce all management systems and control along the food chain, that is from the primary production to the final consumer. The main objective of this work was to implement a food safety reference, FSSC 22000, in a meat processing unit in order to attest its ability to provide safe products, complying with legal requirements and following the requirements of an increasingly competitive and demanding market. As result of the work done throughout the internship, some pre-existing documents were updated as part of the implementation of NP EN ISO 22000:2005, including process flow charts, description of control steps and measures, revision of potencial hazards identification with new categorization of control measures, revision of the operational pre-requisite program, revision of HACCP plan and at least validation, verification and improvement of the food safety management system, including control measures to comply with the standard FSSC 22000. A comparative study between the references NP EN ISO 22000:2005 and FSSC 22000 was also elaborated, where divergences in the structure and requirements were identified. In order to rectify divergences, efforts were made to comply with the requirements, which lead to the creation of new process steps at the diferente stages os production, new types of potential hazards identification and finally preventive measures. It was concluded that, with the effort and commitment of all operators, the processing unit had all the capabilities to successfully implement the food safety standard in question.
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