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Lalanne, Sylvie. "L'hormone folliculostimulante humaine, hFSH : structure, physiopathologie, immunoanalyse." Paris 5, 1990. http://www.theses.fr/1990PA05P208.
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Loureiro, Renan Fernandes. "Caracterização físico-química da foliculotrofina humana (hFSH) recombinante e de suas subunidades, por cromatografia líquida de alta eficiência (HPLC) em fase reversa: comparação com a preparação de referência de hFSH de origem hipofisária do \"National Hormone and Pituitary Program\" dos EUA." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-30032012-100440/.
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Um método de cromatografia líquida de alta eficiência por fase reversa (RP-HPLC) para análise qualitativa e quantitativa do hormônio folículo estimulante humano íntegro (hFSH), foi estabelecido e validado quanto à exatidão, precisão e sensibilidade. O FSH humano é um hormônio glicoprotéico dimérico largamente utilizado em medicina reprodutiva tanto para diagnóstico quanto para terapia. A metodologia desenvolvida preserva a integridade da proteína, permitindo a análise da forma heterodimérica intacta, e não somente de suas subunidades, como é normalmente obtida na maioria das condições geralmente empregadas. Esta técnica foi também utilizada para a comparação da hidrofobicidade relativa de preparações de hFSH hipofisária, urinária e derivadas de células de ovário de hamster chinês (CHO) bem como de outros dois hormônios glicoprotéicos, sintetizados na hipófise anterior: hormônio humano estimulante da tireóide (hTSH) e hormônio luteinizante humano (hLH). O menos hidrofóbico dos três hormônios analisados foi o hFSH, seguido do hTSH e do hLH. Uma diferença significativa (p<0,005) foi observada entre o tempo de retenção (tR) das preparações hipofisária e recombinante de hFSH, refletindo diferenças estruturais nas suas cadeias de carboidratos. Duas isoformas principais foram detectadas no hFSH urinário, incluindo uma forma que foi significativamente diferente (p<0,005) das preparações hipofisária e recombinante. Foram demonstradas linearidade da curva dose-resposta (r=0,9965, n=15) para esta metodologia de RP-HPLC, bem como uma precisão inter-ensaio, cujo coeficiente de variação é menor que 4%, para a quantificação de diferentes preparações de hFSH e uma sensibilidade da ordem de 40 ng. Foram também analisados o comportamento cromatográfico e a hidrofobicidade relativa das subunidades individuais das preparações recombinantes e hipofisária de hFSH. Além disso, a exata massa molecular das subunidades individuais de hFSH e do heterodímero foram simultaneamente determinadas por espectrometria de massa MALDI-TOF. A presente metodologia representa, em nossa opinião, uma ferramenta essencial para a caracterização e controle de qualidade deste hormônio, que ainda não consta das principais farmacopéias.A reversed-phase high-performance liquid chromatography (RP-HPLC) method for the qualitative and quantitative analysis of intact human follicle-stimulating hormone (hFSH) was established and validated for accuracy, precision and sensitivity. Human FSH is a dimeric glycoprotein hormone widely used as a diagnostic analyte and as therapeutic product in reproductive medicine. The technique developed preserves the protein integrity, allowing the analysis of the intact heterodimeric form rather than just of its subunits, as it is the case for the majority of the conditions currently employed. This methodology has also been employed for comparing the relative hydrophobicity of pituitary, urinary and two Chinese hamster ovary (CHO)-derived hFSH preparations, as well as of two other related glycoprotein hormones of the anterior pituitary: human thyroid-stimulating hormone (hTSH) and human luteinizing hormone (hLH). The least hydrophobic of the three glycohormones analyzed was hFSH, followed by hTSH and hLH. A significant difference (p<0.005) was observed in tR between the pituitary and recombinant hFSH preparations, reflecting structural differences in their carbohydrate moieties. Two main isoforms were detected in urinary hFSH, including a form which was significantly different (p<0.005) for the pituitary and recombinant preparations. The linearity of the dose-response curve (r = 0.9965, n = 15) for this RP-HPLC methodology, as well as an inter-assay precision with relative standard deviation less than 4% for the quantification of different hFSH preparations and a sensitivity of the order of 40 ng, were demonstrated. The chromatographic behavior and relative hydrophobicity of the individual subunits of the pituitary and recombinant preparations were also analyzed. Furthermore, the accurate molecular mass of the individual hFSH subunits and of the heterodimer were simultaneously determined by matrix-assisted laser desorption ionization time-of-flight mass spectral analysis (MALDI-TOF-MS). The present methodology represents, in our opinion, an essential tool for characterization and quality control of this hormone that is not yet described in the main pharmacopoeias.
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LOUREIRO, RENAN F. "Caracterização físico-química da foliculotrofina humana (hFSH) recombinante e de suas subunidades, por cromatografia líquida de alta eficiência (HPLC) em fase reversa: comparação com a preparação de referência de hFSH de origem hipofisária do 'National Hormone and Pituitary Program' dos EUA." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11467.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Mageika, Cristiane Moreira de Carvalho. "Preparação e caracterização das subunidades alfa e beta dos hormônios glicoproteicos humanos recombinantes: foliculotrofina, luteotrofina, tereotrofina e sua comparação com os produtos hipofisários." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-10102011-143435/.
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Neste trabalho é descrito um método prático e eficiente para dissociar, em subunidades α e β, quantidades pequenas (da ordem de microgramas) dos hormônios foliculotrofina (hFSH), luteotrofina (hLH) e tireotrofina (hTSH) humana, nativos e recombinantes. A dissociação destes hormônios foi conseguida incubando-os, durante 16 horas, a 37ºC, com diferentes concentrações de ácido acético: 3M, 5M e 0,4M respectivamente para o hFSH, hLH e hTSH. Nestas condições, uma eficiência de dissociação acima de 98% foi obtida. Esta eficiência foi calculada com base nas determinações de massa dos heterodímeros e das subunidades, realizadas por MALDI-TOF-MS. Uma separação rápida e quantitativa das subunidades, com rendimentos da ordem de 80-90%, foi conseguida por cromatografia líquida de alta eficiência em fase reversa (RP-HPLC) em uma coluna C4. As subunidades foram caracterizadas quanto à pureza, hidrofobicidade, massa molecular e distribuição de carga por HPLC de exclusão molecular e fase reversa, SDS-PAGE e focalização isoelétrica. Quando analisadas quanto à hidrofobicidade, as subunidades mostraram-se aproximadamente iguais, enquanto as subunidades β dos três heterodímeros apresentaram a seguinte escala de hidrofobicidade: β-hFSH < β-hTSH < β-hLH. Com relação à massa molecular relativa (Mr), as subunidades α e β do hFSH apresentaram as maiores Mr enquanto as subunidades do hLH as menores. A distribuição dos isômeros de carga das subunidades dos três hormônios ocorreu em uma região ácida, para o hFSH, em uma região básica, para o hLH e em uma região intermediária, para o hTSH. As subunidades α dos três hormônios, quando analisadas via SDS-PAGE, apresentaram praticamente a mesma mobilidade eletroforética, enquanto as subunidades β apresentaram diferentes taxas de migração (mR), sendo mR β-hFSH < mR β-hTSH < mR β-hLH. Diferenças relativas à massa molecular, hidrofobicidade, migração eletroforética e distribuição de carga foram encontradas entre as preparações recombinantes e hipofisárias dos três hormônios. O método descrito é suave, prático e flexível e pode ser adaptado à dissociação de outras glicoproteínas heterodiméricas recombinantes ou nativas. Permite não só estudos e caracterização direta de cada subunidade, como também detectar a presença de subunidades livres em preparações farmacêuticas, que são contaminantes indesejáveis, sendo, portanto, uma ferramenta extremamente útil para o controle de qualidade de produtos farmacêuticos.In this work a practical and efficient method for the dissociation into α-and β-subunits of small amounts (microgram range) of pituitaryderived and recombinant human follicle-stimulating hormone (hFSH), human luteotropin (hLH) and human thyrotropin (hTSH) is described. Dissociation was achieved by overnight treatment of the glycoproteins, at 37ºC, with acetic acid in different concentrations: 3M, 5M and 0,4M for hFSH, hLH and hTSH respectively. In these conditions, a dissociation efficiency of > 98% was attained. This efficiency was calculated on the basis of relative mass determinations of the heterodimers and subunits carried out via mass spectrometry (MALDI-TOF-MS). The α-and β-subunits were rapidly and quantitatively separated by reversed-phase high-performance liquid chromatography (RP-HPLC) on a C4 column with yields of the order of 80-90%. The isolated subunits were characterized concerning their purity, hidrophobicity, molecular mass and charge distribution, via size exclusion and RP-HPLC, SDS-PAGE and isoelectric focusing. When analyzed with relation to the hydrophobicity, the α-subunits presented approximately the same hydrophobicity, while β-subunits showed the following scale: &beta-hFSH < β-hTSH < β-hLH. Concerning molecular mass, α- and β-subunits of hFSH were shown to have the highest while hLH subunits the lowest. Charge isomers of the subunits of the three glycohormones were predominantly distributed in an acidic region for hFSH, in a basic region for hLH, and in a wider pH range (acidic and basic) for hTSH. Similar migration rates (mR), analyzed via SDS-PAGE, were observed for the α-subunits of the three hormones. A greater variation was found for the β-subunits: mR β-hFSH < mR β-hTSH < mR β-hLH. Differences between recombinant and pituitary preparations of three hormones were observed with relation to molecular mass, hydrophobicity, electrophoretic migration and charge distribution. The described method is mild, practical and flexible and can be adapted to dissociate any recombinant or native heterodimeric glycoprotein, allowing studies and direct characterization of each subunit as well as the detection of free subunits that are undesired contaminants in pharmaceutical preparations, being also an extremely useful tool for the quality control of pharmaceutical products.
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Misztal, David Richard Biotechnology & Biomolecular Sciences Faculty of Science UNSW. "Identification of cellular changes associated with increased production of human follicle stimulating hormone in a recombinant Chinese hamster ovary cell line." Publisher:University of New South Wales. Biotechnology & Biomolecular Sciences, 2008. http://handle.unsw.edu.au/1959.4/41326.
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A proteomics approach was used to identify proteins potentially implicated in the cellular response concurrent with elevated production levels of human follicle stimulating hormone in a recombinant Chinese hamster ovary cell line (Darren cells), using zinc and sodium butyrate in the production media to increase expression. To this end, 2-dimensional gel electrophoresis (2-DGE) was utilized. Firstly, several aspects of 2-DGE were developed for this investigation. Gel drying conditions were optimized, and a glycine-free blotting method is described which achieved greater efficiency in rapid transfer of proteins than those previously described. Next, hFSH expression was characterized in Darren cells. An ELISA developed for this investigation examined intracellular (expression) and extracellular (secretion) of hFSH during increased expression. These results show a disproportionate increase in intracellular hFSH (188%) expression above extracellular hFSH (41%).
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Ware, Scott. "HFS Plus File System Exposition and Forensics." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5559.
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The Macintosh Hierarchical File System Plus, HFS+, or as it is commonly referred to as the Mac Operating System, OS, Extended, was introduced in 1998 with Mac OS X 8.1. HFS+ is an update to HFS, Mac OS Standard format that offers more efficient use of disk space, implements international friendly file names, future support for named forks, and facilitates booting on non-Mac OS operating systems through different partition schemes. The HFS+ file system is efficient, yet, complex. It makes use of B-trees to implement key data structures for maintaining meta-data about folders, files, and data. The implementation of what happens within HFS+ at volume format, or when folders, files, and data are created, moved, or deleted is largely a mystery to those who are not programmers. The vast majority of information on this subject is relegated to documentation in books, papers, and online content that direct the reader to C code, libraries, and include files. If one can't interpret the complex C or Perl code implementations the opportunity to understand the workflow within HFS+ is less than adequate to develop a basic understanding of the internals and how they work. The basic concepts learned from this research will facilitate a better understanding of the HFS+ file system and journal as changes resulting from the adding and deleting files or folders are applied in a controlled, easy to follow, process. The primary tool used to examine the file system changes is a proprietary command line interface, CLI, tool called fileXray. This tool is actually a custom implementation of the HFS+ file system that has the ability to examine file system, meta-data, and data level information that isn't available in other tools. We will also use Apple's command line interface tool, Terminal, the WinHex graphical user interface, GUI, editor, The Sleuth Kit command line tools and DiffFork 1.1.9 help to document and illustrate the file system changes. The processes used to document the pristine and changed versions of the file system, with each experiment, are very similar such that the output files are identical with the exception of the actual change. Keeping the processes the same enables baseline comparisons using a diff tool like DiffFork. Side by side and line by line comparisons of the allocation, extents overflow, catalog, and attributes files will help identify where the changes occurred. The target device in this experiment is a two-gigabyte Universal Serial Bus, USB, thumb drive formatted with Global Unit Identifier, GUID, and Partition Table. Where practical, HFS+ special files and data structures will be manually parsed; documented, and illustrated.ID: 031001395; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Title from PDF title page (viewed May 28, 2013).; Thesis (M.S.)--University of Central Florida, 2012.; Includes bibliographical references (p. 131-132).
M.S.
Masters
Computer Science
Engineering and Computer Science
Digital Forensics
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Malásek, Jan. "Vliv selekce příznaků metodou HFS na shlukovou analýzu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221271.
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Master´s thesis is focused on cluster analysis. Clustering has its roots in many areas, including data mining, statistics, biology and machine learning. The aim of this thesis is to elaborate a recherche of cluster analysis methods, methods for determining number of clusters and a short survey of feature selection methods for unsupervised learning. The very important part of this thesis is software realization for comparing different cluster analysis methods focused on finding optimal number of clusters and sorting data points into correct classes. The program also consists of feature selection HFS method implementation. Experimental methods validation was processed in Matlab environment. The end of master´s thesis compares success of clustering methods using data with known output classes and assesses contribution of feature selection HFS method for unsupervised learning for quality of cluster analysis.
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Singh, Sachin. "Analysis of microstrip defected ground structure filters on anisotropic substrates using HFSS /." abstract and full text PDF (free order & download UNR users only), 2005. http://0-wwwlib.umi.com.innopac.library.unr.edu/dissertations/fullcit/3209134.
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Thesis (Ph. D.)--University of Nevada, Reno, 2005."December 2005." Includes bibliographical references (leaves 213-220). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm.
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Costa, Rodrigo Carvalho Souza. "Estudo experimental e numÃrico de uma antena ressoadora dielÃtrica baseada em CaTi1Âx(Nb2=3Li1=3)xO3ÂÂ (CNLTO) e CaTi1Âx(Nb1=2Ln1=2)xO3 (Ln = Bi (CNBTO) e Fe (CNFTO)) para aplicaÃÃes em bluetooth." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2043.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoCoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
O progresso da indÃstria de telecomunicaÃÃes depende da fabricaÃÃo em larga escala de circuitos de baixo custo, alto desempenho elÃtrico, confiabilidade e passividade de miniaturizaÃÃo. Estas caracterÃsticas sÃo necessÃrias para garantir que os sinais transmitidos sejam confinados a uma freqÃÃncia bem definida, evitando assim sinais que possam interferir no desempenho satisfatÃrio de sistemas de telecomunicaÃÃes. As cerÃmicas dielÃtricas fornecem vantagens significantes em termos de compactaÃÃo, peso, estabilidade tÃrmica e custos de produÃÃo em dispositivos de micro-ondas, alÃm de possuir uma grande facilidade de integraÃÃo com outros circuitos integrados de microondas. Este trabalho consiste no desenvolvimento e caracterizaÃÃo de um novo tipo de material cerÃmico para ser utilizado como uma antena miniatura para aplicaÃÃes em Bluetooth (2.4 GHz). O trabalho està dividido em trÃs etapas. A primeira consiste em desenvolver um novo material que possua constante dielÃtrica (25 < Âr < 50), um alto fator de qualidade (Q > 5000) e um coeficiente de temperatura da freqÃÃncia de ressonÃncia (Âf ) prÃximo de zero. A segunda consiste em caracterizar o material desenvolvido atravÃs de DifraÃÃo de Raios-X e Espectroscopias Raman, Infra-vermelho e DielÃtrica. A Ãltima etapa consiste em fabricar e simular a antena feita com o material desenvolvido, comparando o desempenho teÃrico com o prÃtico.
The progress of telecommunication industry is highly dependent of the fabrication of low cost, quality factor and smaller size of the individual components for commercial applications. This kind of characteristics are necessary to warranty that the signal have well suited frequency, avoiding the noise interference signals, that could affect the performance of the telecommunication systems. Dielectric ceramics have significant advantages of light weight, low cost, small size, low profile, high radiation eficiency, low production cost and ease of integration with other active or passive microwave integrated circuit. This work will provide a new ceramic material that could be used in a miniature antenna for Bluetooth applications. This work is divided in three stages. The first one is develop a new material with a good dielectric permittivity (25 < Âr < 50), high quality factor (Q > 5000) and low temperature coeficient of resonant frequency (Âf ). The second one characterize the developed material by XDR, Raman, Infrared and dielectric spectroscopy in microwave region. The last one is build and simulate the antenna made with the developed dielectric material.
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Khan, Raja Sheharyar, and Muhammad Ishfaq. "A Compact Microstrip Patch Antenna for LTE Applications." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-24505.
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A compact multiband antennas for Long Term Evolution (LTE) applications is a challenge. Both the frequencies of new wireless technologies and new frequency bands must be covered. The lower end of the 0.7- 3.5 GHz band is especially difficult to handle for miniaturized terminal devices. A single layer, line-feed rectangular microstrip patch antenna is small enough for the LTE handsets. Our project proposes size reduction and bandwidth enhancement through adapted feeding techniques. By means of slits the return loss and gain can be optimized with the aid of HFSS (High Frequency Structure Simulator).
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Wang, Mengmeng, and 王萌萌. "Temporal analysis on HFS+ and across file systems in digital forensic investigation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50900122.
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In computer forensics, digital evidence related to time is both important and complex. The rules of changes in time associated with digital evidence, such as files or folders, can be used to analyze certain user behaviors like data access, modification or transfer. However, the format and the rules in time information for user actions are quite different for different file systems, even for different versions of operating systems with the same file system.
Some research on temporal analysis has already been done on NTFS and FAT file systems, while there are few resources that describe temporal analysis on the Hierarchical File System Plus (HFS+), the default file system in Apple computer. Moreover, removable devices like USB disks are used frequently; transferring files and folders between different devices with different file systems and operating systems happens more and more frequently, so the changes of times across different file systems are also crucial in digital forensics and investigations.
In this research, the changes in time attributes of files and folders resulting from user actions on the HFS+ file system and across file systems are analyzed, and the rules of time are generated by inductive reasoning to help reconstruct crime scenes in the digital forensic investigation. Since inductive reasoning is not definitely true compared with deductive reasoning, experiments are performed to validate the rules. The usage of the rules is demonstrated by analyzing a case in details. The methods proposed here are efficient, practical and easy to put into practice in real scenarios.published_or_final_version
Computer Science
Master
Master of Philosophy
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Parikh, Kunal. "Simulation of Rectangular, Single-Layer, Coax-Fed Patch Antennas Using Agilent High Frequency Structure Simulator (HFSS)." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9663.
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The Range Limited Antenna (RLA) is a device, which accurately estimates the range of incoming signals and rejects those that arrive from outside a certain, pre-determined range. This task is accomplished by using two multi-element arrays and applying direction finding (DF) algorithms on each of them. Rectangular, single-layer, coax-fed patch antennas are used as array elements for the specific purpose of tracking cell phones operating in the PCS band inside a given building. It is vital to ensure that the patch antenna is designed in such a manner that it resonates at the desired frequency.
This thesis introduces the Agilent High Frequency Structure Simulator (HFSS) as an effective tool for modeling electromagnetic structures. It presents a comprehensive and meticulous description of the process of modeling a rectangular coax-fed patch antenna in HFSS. Plots of S-parameter values are calculated and are compared with WIPL-D, which is another simulation software program, and with measurements performed at the George Washington University. Various important parameters of the HFSS simulation are varied and their effects are investigated to provide a deeper understanding of the program.Master of Science
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Joseph, Kevin [Verfasser], and Ulrich [Akademischer Betreuer] Hofmann. "HFS and the brain: multiscale effects of electrical stimulation on a neurotransmitter system." Freiburg : Universität, 2018. http://d-nb.info/1202010903/34.
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Aldimassi, Abdel Majid. "Elaboration et caractérisation magnétiques et structurales de nanostructures de FeCoB optimisées pour des applications radiofréquences." Thesis, Brest, 2020. http://www.theses.fr/2020BRES0014.
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Dans ce mémoire, nous avons étudié dans un premier temps des couches minces de Fe43Co43B14/SiO2 en faisant varier l’angle d’incidence (α = 0°, 25° , 45° et 75°) à épaisseur fixe, puis nous avons effectué des mesures sur une série d’échantillons de différentes épaisseurs pour chacun des angles d’incidences de dépôt. Les propriétés magnétiques statiques et dynamiques ont été caractérisées. Le rôle de la dispersion d’anisotropie a notamment été étudié. Ensuite, les propriétés magnétiques de ces échantillons ont été utilisées pour étudier l’intérêt de coupler ces couches minces à des surfaces absorbantes, constituées de différents motifs, notamment périodiques. Les résultats majeurs de cette thèse, indiquent que le FeCoB déposé à 45° est un bon candidat pour les applications hyperfréquences avec des fréquences de résonance élevées (fr ≅ 6 GHz), une valeur de la perméabilité proche de 100 et un champ d’anisotropie de l’ordre de 200 Oe à forte épaisseurIn this thesis, we have initially studied thin films of Fe43Co43B14/SiO2 by varying the incidence angle (α = 0°, 25°, 45° and 75°) at a fixed thickness, then we have performed measurements on a series of samples of different thicknesses for each of the deposited incidence angles. Static and dynamic magnetic properties have been characterized. In addition, the role of anisotropy dispersion has been studied. Then, the magnetic properties of these samples have been used to study the interest of coupling these thin films to absorbent surfaces made up of different patterns, in particular periodic ones. The major results of this thesis, show that FeCoB deposited at 45° is a good candidate for high frequency applications with high resonance frequencies (fr ≅ 6 GHz), permeability value close to 100 and anisotropy field of the order of 200 Oe at high thickness
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Moravec, Petr. "Toolbox pro spolupráci MATLABu s externími simulačními programy." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218046.
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In this Master's thesis scripting interface of two programs CST Microwave studio and Ansoft HFSS for the purpose of analysis of electromagnetic structures is described. The work is focuses control of these programs with help of scripting languages and system's interface of MS Windows XP. Next the process of connecting programs with MATLAB is shown on commented scripts together with an example of complete analysis of a chosen problem, and the import and export of results results in MATLAB. Further the functions which form programming interface between MATLAB and simulation programs are designed and implemented. The interconnection layer makes the complete control of simulating programs possible using the function description published in the official documentation of used simulation programs. The layer is described in reference manual in detail and it is used for optimization with use of Particle swarm optimalization (PSO) of planar antenna model. Then there is presented another usage of the layer for an implementation of global optimization methods - SOMA and DE including suggestion of process for comparison efficiency of optimization algorithms on simple electromagnetic models.
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Kawser, Mohammad Tawhid. "Investigation of a Novel Dual Band Microstrip/Waveguide Hybrid Antenna Element." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/33660.
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Microstrip antennas are low in profile, light in weight, conformable in structure and are now developed for many applications. The main difficulty of the microstrip antenna is its narrow bandwidth. Several modern applications like satellite communications, remote sensing and multi-function radar systems will find it useful if there is dual band antenna operating from a single aperture. Some applications require covering both transmitting and receiving frequency bands which are spaced apart. Providing multiple antennas to handle multiple frequencies and polarizations becomes especially difficult if the available space is limited as with airborne platforms and submarine periscopes.
Dual band operation can be realized from a single feed using slot loaded or stacked microstrip antenna or two separately fed antennas sharing a common aperture. The former design, when used in arrays, has certain limitations like complicated beam forming or diplexing network and difficulty to realize good radiation patterns at both the bands. The second technique provides more flexibility with separate feed system as beams in each frequency band can be controlled independently. Another desirable feature of a dual band antenna is easy adjustability of upper and lower frequency bands.
This thesis presents investigation of a new dual band antenna, which is a hybrid of microstrip and waveguide radiating elements. The low band radiator is a Shorted Annular Ring (SAR) microstrip antenna and the high band radiator is an aperture antenna. The hybrid antenna is realized by forming a waveguide radiator in the shorted region of the SAR microstrip antenna. It is shown that the upper to lower frequency ratio can be controlled by the proper choice of various dimensions and dielectric material. Operation in both linear and circular polarization is possible in either band. Moreover, both broadside and conical beams can be generated in either band from this antenna element.
Finite Element Method based software, HFSS and Method of Moments based software, FEKO were employed to perform parametric studies of the proposed dual band antenna. The antenna was not tested physically. Therefore, in most cases, both HFSS and FEKO were employed to corroborate the simulation results.Master of Science
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Varatharajan, Thirugnanasambantham Ramya [Verfasser]. "Neurophysiological and neurohumoral changes by High Frequency Stimulation (HFS) of Nucleus Accumbens (NAc) / Ramya Varatharajan Thirugnanasambantham." Lübeck : Zentrale Hochschulbibliothek Lübeck, 2015. http://d-nb.info/1079431209/34.
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Khamis, Youssouf Khamis. "Modélisation de transformateurs planaires intégrés." Thesis, Saint-Etienne, 2014. http://www.theses.fr/2014STET4006/document.
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L’utilisation des composants passifs a connu une importante croissance ces dernières décennies notamment dans le domaine de la téléphonie mobile, de l’électronique embarquée. Les travaux présentés dans cette thèse s’inscrivent dans un cadre de projet entre les laboratoires LT2C de l’UJM et Ampère de l’INSA de LYON. L’objectif visé par cette thèse est la modélisation des micro-transformateurs de signaux utilisés pour isoler les parties puissance (Driver IC) et commande (JFET ou MOSFET). Les points abordés dans cette thèse sont le choix des structures de transformateurs qui répondent aux exigences du projet, le développement d’un modèle de transformateur qui prend en compte notamment les pertes et l’évolution de la perméabilité du matériau magnétique et les différents couplages capacitifs. Des simulations à l’aide de HFSS ont été réalisées afin de réaliser le design des structures retenues et valider le modèle développé. Des étapes de fabrications compatibles avec celle de la microélectronique ont été utilisées pour fabriquer des prototypes à une couche et à deux couches de matériau magnétique avec différentes configurations. Une caractérisation haute fréquence (2MHz-200MHz) à l’aide de l’analyseur vectoriel de réseaux a été réalisée et enfin une étude comparative entre les résultats de simulation et les résultats de mesure fait l’objet d’une présentationThe use of passive components has known a significant increasing in the recent decades particularly in the area of mobile telephony, portable or embarked systems. The work presented in this thesis is a part of a project between the two laboratories: LT2C of UJM and AMPERE of INSA of Lyon. The purpose of this thesis is to find a model for signal micro-transformers used to isolate the power part (Driver IC) from the control part of the project (JFET or MOSFET). The essential parts of this thesis concern the choice of transformer structures that deal with the requirements of the project, the development of a transformer model that takes into account the losses and the permeability evolution of the magnetic material versus frequency and the different capacitive couplings. Numerous simulations using HFSS were performed in order to design the chosen structures and to validate the developed transformer model. Different steps compatible with the microelectronics manufacturing have been used to manufacture prototypes with a single magnetic layer and two magnetic layers for the different configurations. High frequency characterization (2MHz-200MHz) using the vector network analyzer was performed and finally a comparative study between the results of simulation and measurements has been the subject of a presentation
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Chen, Luyi. "DUAL FREQUENCY PATCH ANTENNA DESIGN FOR GLOBAL NAVIGATION SATELLITE SYSTEM." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1178633247.
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Robledo, Leiva Juan Pablo Salvador. "Simulaciones Electromagnéticas Computacionales de Fotodiodos Utc-Tw." Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/104234.
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No autorizada por el autor a ser publicada a texto completoEl objetivo de la presente memoria es simular el comportamiento electromagnético del fotomezclador UTC-TW como es parte de un proyecto de desarrollo del laboratorio de Fotónica-THz del Departamento de Ingeniería Eléctrica. La memoria comienza con una revisión de conceptos básicos de teoría de microondas, teoría de antenas, el método de elementos finitos y las características más importantes de la estructura UTC-TW. Además se reseñan las características más importantes de dos programas para la simulación de estructuras a altas frecuencias con el método de elementos finitos: HFSS y CST MicroWave Studio. Luego, se indica la forma en que fueron parametrizadas las dimensiones del dispositivo en los softwares HFSS y CST, las características del equipo computacional utilizado y la forma en que se analiza el dispositivo. Con esto se obtienen los primeros resultados y se los presenta. A continuación se muestran los pasos seguidos para obtener un modelo con bajo costo computacional de la estructura para el análisis en frecuencia en el software HFSS. Se encuentra que es imposible obtener resultados útiles en HFSS debido a limitaciones de memoria RAM, lo que obliga a migrar el diseño a CST donde se realiza un análisis en el dominio del tiempo o transitorio. En CST se obtienen resultados convincentes a un menor costo en memoria y tiempo de computación, los que se comparan con resultados de un diseño simplificado en HFSS. Finalmente se hace una comparación entre HFSS y CST MWS y se concluye que CST es la mejor alternativa para el tipo de estructura estudiada dada la situación actual del equipo computacional disponible. Además se proponen alternativas al método de elementos finitos para la simulación del dispositivo y se indican algunas consideraciones para simulaciones futuras en HFSS y CST.
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Fernandes, Tatiana Sainara Maia. "Estudo da estabilidade tÃrmica da liga Ca(Nb1/2Bi1/2)xTi1-xO3:(B2O3)y para uso em antena ressoadora dielÃtrica (DRA)." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7444.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoO campo da comunicaÃÃo sem fio vem passando por um crescimento revolucionÃrio nas Ãltimas dÃcadas. Isto à atribuÃdo à invenÃÃo de telefones celulares portÃteis. O sucesso da segunda geraÃÃo (2G) dos serviÃos de comunicaÃÃo de telefonia celular, motiva o desenvolvimento de banda larga de terceira geraÃÃo (3G) de telefones celulares e outros produtos e serviÃos sem fio, como por exemplo, o Bluetooth. Este trabalho consiste no desenvolvimento e caracterizaÃÃo de dois sistemas cerÃmicos tendo como base uma matriz de titanato de cÃlcio (CaTiO3) com substituiÃÃo de Ãons titÃnio por Ãons de niÃbio associados com bismuto (Ca (Nb1/2Bi1/2)xTi1-xO3; x=0.7 e 0.8), visando a adiÃÃo de B2O3 para diminuiÃÃo da temperatura de sinterizaÃÃo e melhorar a densificaÃÃo, e posteriormente, verificar as modificaÃÃes ocorridas nas propriedades do material, como por exemplo, o coeficiente de temperatura da frequÃncia ressonante (τf). As sÃries cerÃmicas foram produzidas a partir da reaÃÃo no estado sÃlido, com a utilizaÃÃo de moagem mecÃnica de alta energia e tratamento tÃrmico. A caracterizaÃÃo estrutural foi feita atravÃs de Microscopia EletrÃnica de Varredura (MEV) e Picnometria. Foram realizados experimentos para avaliaÃÃo do comportamento elÃtrico e dielÃtrico das amostras, na faixa de Microondas e RÃdio-FrequÃncia (temperatura ambiente e com variaÃÃo de temperatura). Por fim, o material foi testado como uma antena ressoadora dielÃtrica, e posteriormente os resultados obtidos foram simulados atravÃs do programa HFSS (Ansoft High Frequency Structure Simulator). Os materiais cerÃmicos produzidos tiveram suas propriedades elÃtricas, dielÃtricas e como antena bastante afetadas com a adiÃÃo do B2O3.
The field of wireless communication has undergone a revolutionary growth in recent decades. This is attributed to the invention of wireless mobile phones. The success of second generation (2G) services of cellular communication, motivates the development of broadband third generation (3G) mobile phones and other wireless products and services, such as Bluetooth. This work describes the development and characterization of two ceramic systems based on a matrix of calcium titanate (CaTiO3) with substitution of titanium ions by niobium ions associated with bismuth (Ca (Nb1/2Bi1/2) xTi1-xO3, x = 0.7 and 0.8), aiming the addition of B2O3 to reduce the sintering temperature and to improve densification, and thus verify the modifications on material properties, such as the temperature coefficient τf. The ceramic series are produced from solid state reaction with the use of high energy mechanical milling and heat treatment. The structural characterization was performed by Scanning Electron Microscopy (SEM) and Pycnometry. Experiments were done to evaluate the dielectric behavior of samples in the range of Microwave and Radio Frequency (room temperature and with temperature variation). Finally the material was tested as a dielectric resonator antenna, and posteriorly the results were simulated using HFSS program (Ansoft High Frequency Structure Simulator). The produced ceramics have had their electrical, dielectric and antenna properties quite affected with the addition of B2O3.
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Grénar, Milan. "Implementace pokročilé filtrace s klasifikací paketů pro bezdrátové sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218953.
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The diploma thesis addresses facility of QoS control with GNU/Linux tools iptables and iproute. An attention is focused especially on HTB and HFSC traffic shaping methods with regard to utilization in wireless networks. The paper also includes a simulation of ensuring QoS in wireless network with 802.11e amendment.
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Aba, Baaddi. "Étude thermodynamique de certains alliages binaires en métaux de transition par calorimétrie à haute température : cas des systèmes tiru, tirh, tiir, zrir, hfru, hfrh, hfir." Nancy 1, 1992. http://www.theses.fr/1992NAN10141.
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Cette étude thermodynamique est une contribution expérimentale a la connaissance du comportement des alliages de métaux de transition. Les enthalpies de formation de 23 composes binaires, formes d'un métal de la colonne 4 (ti, zr, hf) et d'un métal du groupe du fer, ont été mesurées par réaction de synthèse directe à hautes températures dans un calorimètre spécialement conçu. Des contrôles métallographiques et structuraux ont été réalisés systématiquement. Les résultats montrent que: (a) les variations de l'enthalpie de formation, en fonction de la position des composants dans la classification périodique, ne peuvent pas être décrites de façon simple, (b) les modèles théoriques de prévisions des enthalpies de formation, bien qu'encore imparfaits, font actuellement beaucoup de progrès. Enfin, une utilisation du logiciel thermo-calc a mené à la modélisation numérique complète de deux systèmes: hfir et zrir
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Rosenthal, Thomas [Verfasser], and Alfred [Akademischer Betreuer] Oppolzer. "Pflegemanagement im Fernstudium : eine Evaluationsstudie zum Qualifikationsprofil des Diplomstudienganges Pflegemanagement an der Hamburger Fern-Hochschule (HFH) / Thomas Rosenthal. Betreuer: Alfred Oppolzer." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/111318437X/34.
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V, K. Thalakkatukalathil Vinod. "Electromagnetic modeling and characterization of anisotropic ferrite materials for microwave Isolators/Circulators." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0134/document.
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Les circulateurs et les isolateurs à ferrite sont couramment utilisés dans l’électronique hyperfréquence en raison de leur forte résistivité électrique et de leur aimantation spontanée élevée. La conception et l’optimisation des dispositifs micro-ondes à ferrites nécessitent d’une part la connaissance de leurs propriétés dynamiques, permittivité complexe et tenseur de perméabilité, et d’autre part le contrôle de la propagation de l’onde électromagnétique (EM) qui conditionne leurs performances. Les logiciels commerciaux de simulation utilisent différents modèles théoriques pour décrire le tenseur de perméabilité en fonction de l’état d’aimantation. Cependant la plupart de ces simulateurs EM restent limités à des états particuliers d’aimantation en raison des hypothèses simplificatrices des modèles de perméabilité utilisés. Dans ce travail de thèse, nous présentons un outil prédictif pour l’étude des propriétés EM des ferrites quel que soit leur état d’aimantation et qui tient compte de l’inhomogénéité des champs internes de polarisation. Cette modélisation combine des techniques expérimentales de détermination des paramètres physiques des ferrites et un modèle théorique qui utilise ces paramètres pour décrire le comportement dynamique des ferrites quel que soit l’état d’aimantation. Dans la première partie de la thèse nous présentons une méthode large bande en ligne coaxiale pour la mesure du coefficient d’amortissement. Les paramètres S théoriques sont calculés à partir d’une analyse EM (problème direct) de la cellule de mesure. Pour le problème inverse, une optimisation numérique a été développée pour calculer le coefficient d’amortissement (α) par comparaison des paramètres S calculés avec ceux mesurés. Dans la seconde partie de la thèse, nous présentons un outil théorique de modélisation EM qui combine une analyse magnétostatique, un modèle du tenseur de perméabilité généralisé (GPT) et le simulateur Ansys HFSSTM. La majorité des paramètres d’entrée comme l’aimantation à saturation ou le champ d’anisotropie peuvent être mesurés à l’aide de techniques standards de caractérisation statique. Seul le paramètre dynamique, le coefficient d’amortissement, est déterminé à l’aide de la technique en ligne coaxiale proposée dans la première partie de la thèse. L’outil théorique développé est ensuite validé par la modélisation et la réalisation d’un circulateur micro-ruban à jonction Y. Grâce à la prise en compte de l’inhomogénéité des champs internes de polarisation, l’outil théorique proposé permet de mieux prédire le comportement dynamique des dispositifs à ferrites et cela pour tout état d’aimantationFerrites are widely used in microwave electronics, particularly for circulators and insulators, because of their high electrical resistivity and high spontaneous magnetization. Design and optimization of microwave devices using ferrites requires realistic knowledge of its dynamic response, namely complex permittivity and permeability tensor and, on the other hand, control of wave propagation that condition their performance. Commercial simulation software use different theoretical models to describe the permeability tensor according to the state of magnetization. However, most of the electromagnetic (EM) simulators remain limited to certain states of magnetization, due to the simplified assumptions on which their permeability models are based upon.In this thesis work, we presented a predictive electromagnetic tool to study the EM properties of ferrites, whatever their magnetization state is, and takes into account the inhomogeneity of the internal polarization fields. This theoretical modeling approach combines experimental techniques to find the physical parameters of the ferrites, and a theoretical model which will use these parameters to describe the dynamic behavior of ferrites at any magnetization state.In the first part of the thesis, we presented a broadband coaxial line method for damping factor measurement. Theoretical S parameters are calculated using the EM analysis (direct problem) of the measurement cell. In the inverse problem, a numerical optimization procedure is developed to compute the damping factor (α) by matching theoretical S parameters with measured S parameters.During the second part of the thesis, we developed a theoretical EM modeling tool which combines a magneto-static solver, generalized permeability tensor model and commercial simulation software Ansys HFSSTM. Most of the input parameters like saturation magnetization, anisotropy field, etc. can be measured using standard characterization methods, except the damping factor used to represent the dynamic losses. Static input parameters of this theoretical tool are determined using standard material characterization methods.Dynamic input parameter, damping factor is calculated using the coaxial line technique proposed in the first part of this thesis. Theoretical EM tool is validated by modeling, and realizing a microstrip Y-junction circulator. By taking into account the inhomogeneity of the internal polarizing fields, proposed theoretical tool can predict the dynamic behavior of ferrite devices more accurately, at all magnetization states
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Cutshall, Ryan Thomas. "Achieving Wide Bandwidth Electrically Small Antennas Using Internal Non-Foster Elements." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/305873.
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Electromagnetic equations pertaining to electrically small dipole antennas and electrically small monopole antennas with small circular ground planes are reviewed. Two electrically small antenna designs are analyzed numerically and the results are compared. The first is a frequency agile version of the two-dimensional (2D) planar Egyptian axe dipole (EAD) antenna. The second is its three-dimensional (3D) counterpart. The frequency agile performance characteristics of both the 2D and 3D EAD designs are studied and compared. The potential for non-Foster augmentation to achieve large instantaneous fractional impedance bandwidths is detailed for each antenna. In addition, details are given on how to run frequency agile simulations in both ANSYS HFSS and Agilent's ADS. Details are also provided on how to generate an antenna's non-Foster |S₁₁| and radiation efficiency curves using HFSS, and how to generate an antenna's non-Foster |S₁₁| curve using ADS.
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Atefi, Seyed Reza. "Electrical Bioimpedance Cerebral Monitoring : From Hypothesis and Simulation to First Experimental Evidence in Stroke Patients." Doctoral thesis, KTH, Medicinska sensorer, signaler och system, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176634.
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Stroke is amongthe leading causes of death worldwide and requires immediate care to prevent death or permanent disability. Unfortunately, the current stateof stroke diagnosis is limited to fixed neuroimaging facilities that do not allow rapid stroke diagnosis. Hence, a portable stroke-diagnosis device could assist in the pre-hospital triage of patients. Moreover, such a portable device could also be useful for bedside stroke monitoring of patients in the Neuro Intensive Care Unit (Neuro-ICU) to avoid unnecessary neuroimaging. Recent animal studies and numerical simulations have supported the idea of implementing Electrical Bioimpedance (EBI) in a portable device, allowing non-invasive assessment as a useful tool for the pre-hospital triage of stroke and Traumatic Brain Injury (TBI) patients. Unfortunately, these studies have not reported any results from human subjects in the acute phase of the stroke. The numerical simulations are also based on simple models that sometimes lack necessary details. Finite Element Method (FEM) simulations on a realistic numerical head model as well as experimental Bioimpedance Spectroscopy (BIS) measurements from human subjectsin the acute, subacute and chronic phasesof stroke were used to answer the following research questions: (i) Does stroke modify the electrical properties of brain tissue in a way that is detectable via EBI? (ii) Would it be possible to detect stroke via EBI as early as in the acute and sub-acute phase?(iii) Is EBI sensitive enough to monitor changes caused by stroke pathogenesis? Using FEM to simulate electrical current injection on the head and study the resulting distribution of electrical potential on the scalp, it was shown that Intra-Cranial Hemorrhage (ICH) affects the quasi-symmetric scalp potential distribution,creating larger left-right potential asymmetry when compared to the healthy head model. Proof-of-concept FEM simulations were also tested in a small cohort of 6ICH patients and 10 healthy controls, showing that the left-right potential difference in the patients is significantly (p<0.05) larger than in the controls. Using bioimpedance measurements in the acute, subacute and chronic phasesof stroke and examining simple features, it was also shown that the head EBI measurements of patients suffering stroke are different from controls, enabling the discrimination of healthy controls and stroke patients at any stage of the stroke. The absolute change in test-retest resistance measurements of the control group (~5.33%) was also found to be significantly (p<0.05) smaller than the EBI measurements of patients obtained 24 hours and 72 hours after stroke onset (20.44%). These results suggested that scalp EBI is sensitive to stroke pathogenesis changesand thususeful for bedside monitoring in the Neuro-ICU. These results suggested that EBI is a potentially useful tool for stroke diagnosis and monitoring. Finally, the initial observations based on a small number of patients, addressing the proposed future work of this thesis, suggested that the average head resistance amplitude of hemorrhagic stroke patients is smaller than in healthy controls, while ischemic stroke patients show a larger resistance amplitude than the controls. Scalp potential asymmetry analysis of healthy, hemorrhagic and ischemic stroke subjects also suggests that these three groups can be separated. However, these results are based on a small number of patients and need to be validated using a larger cohort. Initial observations also showed that the resistance of the EBI measurements of controls is robust between test and retest measurements, showing no significant difference (less than 2% and p>0.05). Subject position during EBI recording (supine or sitting) did not seem to affect the resistance of the EBI measurements (p>0.05). However, age, sex and head size showed significant effects on the resistance measurements. These initial observations are encouraging for further research on EBI for cerebral monitoring and stroke diagnosis. However, at this stage, considering the uncertainties in stroke type differentiation, EBI cannot replace CT but has the potential to be used as a consultation tool.QC 20151109
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Bernard, Cyrielle. "Concentration et fractionnement des terres rares dans les complexes alcalins : le rôle des fluides." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30187.
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Les terres rares (TR) sont un groupe de métaux utilisés dans de nombreuses nouvelles technologies. Leur production est limitée, il est donc important de trouver de nouvelles sources d'approvisionnement. Les TR sont divisées en TR légères et lourdes, ces-dernières étant plus rares et ayant plus d'applications. Les granites et pegmatites alcalins sont des roches riches en TR lourdes. Une partie de cet enrichissement est d'origine magmatique, mais le rôle des fluides hydrothermaux (i.e. eau, CO2, méthane surtout) pose question. Ce manuscrit se concentre sur l'étude de minéraux communs (amphiboles, pyroxène, zircon) et des inclusions fluides de six zones du monde pour comprendre l'impact des fluides hydrothermaux par rapport à celui des processus magmatiques dans les granites et pegmatites alcalins. Les résultats montrent que la concentration et le fractionnement des TR sont liés à la circulation de fluides hydrothermaux riches en Na et K ou Ca et Na à des températures inférieures à 400 °CThe rare earth elements (REE) are a group of metallic elements used in many modern technologies. Their worldwide production is limited, hence it is necessary to find more sources. The REE are divided in light REE and heavy REE, the latter being rarer and with more industrial uses. Alkaline granites and associated pegmatites are rocks rich in heavy REE. Part of this enrichment is known to be magmatic, but the role of hydrothermal fluids (mostly water, CO2 and/or methane) in concentrating and fractionating these elements remains unclear. This work focuses on the study of minerals (amphiboles, pyroxene, zircon mostly) and fluid inclusions in six locations. The influence of hydrothermal fluids on REE relatively to magmatic processes is investigated in alkaline granites and associated pegmatites. The results show that REE concentration and fractionation is indeed linked to the circulation of hydrothermal fluids that are Na-K-rich or Ca-Na-rich and circulate at temperatures below 400 °C
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Jones, David A. "Characterization of a Phased Array Feed Model." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2447.pdf.
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Silva, Paulo Maria de Oliveira e. "Estudo dos efeitos da adiÃÃo de ZnO e Nb2O5 nas propriedades dielÃtricas da matriz cerÃmicas BaBi4Ti4O15 (BBT) e suas aplicaÃÃes em antenas." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10945.
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nÃo hÃCom o rÃpido crescimento das indÃstrias de telecomunicaÃÃes criou-se uma forte necessidade por materiais cerÃmicos para aplicaÃÃes em micro-ondas. Devendo estes materiais apresentar alta permissividade dielÃtrica (εr), elevado fator de qualidade (Q), boa estabilidade tÃrmica (τf Â10 ppm/ÂC) e baixo custo. Com a invenÃÃo de telefones celulares portÃteis, o campo da comunicaÃÃo sem fio passou por um crescimento inovador nas Ãltimas dÃcadas. O sucesso da terceira geraÃÃo (3G) dos serviÃos de comunicaÃÃo de telefonia celular, motiva o desenvolvimento de banda larga de quarta geraÃÃo (4G) de telefones celulares e outros produtos e serviÃos sem fio, como por exemplo, o Bluetooth. Este trabalho consiste no desenvolvimento e caracterizaÃÃo da cerÃmica de titanato de bÃrio-bismuto (BaBi4Ti4O15) com adiÃÃo de Ãxido de niÃbio (Nb2O5) ou Ãxido de zinco (ZnO), visando a diminuiÃÃo da temperatura de sinterizaÃÃo e possivelmente melhorar a densificaÃÃo, e posteriormente, verificar as modificaÃÃes ocorridas nas propriedades do material, como por exemplo, o coeficiente de temperatura da frequÃncia ressonante (τf). As sÃries cerÃmicas foram produzidas usando a reaÃÃo no estado sÃlido, com o uso de moagem mecÃnica de alta energia e tratamento tÃrmico. A caracterizaÃÃo estrutural foi realizada com base na Microscopia EletrÃnica de Varredura (MEV) e Picnometria. As densidades relativas das amostras adicionadas com (ZnO) a de maior concentraÃÃo teve valor de 77% enquanto que o BBT puro o valor foi de 56%. As densidades relativas das amostras adicionadas com (Nb2O5) a de maior concentraÃÃo teve valor de 61% em relaÃÃo ao BBT puro. Foram realizados experimentos para avaliaÃÃo do comportamento elÃtrico e dielÃtrico das amostras, na faixa de Micro-ondas e RadiofrequÃncia (temperatura ambiente e com variaÃÃo de temperatura). Por fim, o material foi testado como uma DRA, e posteriormente os resultados obtidos foram simulados atravÃs do programa HFSS. As caracterÃsticas da DRA da cerÃmica pura sÃo 1,12dBi de ganho e 32,51% de eficiÃncia. A DRA que foi adicionada com 2% de (ZnO) apresentou ganho de 1,16dBi com 33,96% de eficiÃncia, enquanto a que foi adicionada com 5% de (Nb2O5) apresentou 1,41dBi de ganho com 42,21% de eficiÃncia.
With the rapid growth of the telecommunications industry created a strong need for ceramic materials for applications in microwave. These materials should exhibit high dielectric permittivity (εr), high quality factor (Q), good thermal stability (τf Â10 ppm/ÂC) and low cost. With the invention of mobile phones, the field of wireless communication has undergone a revolutionary growth in recent decades. The success of the third generation (3G) services in mobile communication, motivates the development of broadband fourth generation (4G) of mobile phones and other wireless products and services, such as Bluetooth. Nowadays it is well known the use of tablets, which are increasingly gaining market and encouraging the development of new technologies to improve the flow of information. This work involves the development and characterization of the barium bismuth titanate ceramic, (BaBi4Ti4O15) with addition of niobium oxide (Nb2O5) or zinc oxide (ZnO) in order to decrease the sintering temperature and possibly improve the densification and subsequently check the modifications on material properties, such as the temperature coefficient of resonant frequency (τf). The series ceramics were produced using the solid state reaction with the use of high energy mechanical milling and heat treatment. The structural characterization was performed based on Scanning Electron Microscopy (SEM) and Measurement by Pycnometer. The relative densities of the samples with added (ZnO) had the highest concentration value of 77% pure BBT while the value was 56%. The relative densities of the samples spiked with (Nb2O5) had the highest concentration value of 61% compared to pure BBT. Experiments were conducted to evaluate the electrical and dielectric behavior of the samples in the range of Microwave and Radio Frequency (temperature and temperature variation). Finally, the material was tested as a DRA, and then the results were simulated using the HFSS program. The characteristics of the pure ceramic DRA are 1,12dBi gain and 32,51% efficiency. The DRA added with 2% (ZnO ) showed 1.16dBi gain with 33,96% efficiency , while the one that was added with 5% (Nb2O5) showed gain of 1.41dBi with 42,21% efficiency.
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Solana, Gabriel A. "Modeling of Crosstalk in High Speed Planar Structure Parallel Data Buses and Suppression by Uniformly Spaced Short Circuits." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/606.
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The aim of this thesis is to identify coupling mechanisms for three line microstrip, stripline and microstrip with dielectric overlay structures as either inductive or capacitive, quantify through simulation and measurement the amount of crosstalk to be expected in terms of scattering parameters. A new method of crosstalk suppression is implemented into each three line structure by placing uniformly spaced short circuits down the length of the center transmission line.
All structures were simulated over various physical and electrical parameters. Select microstrip structures, shielded and unshielded, were fabricated and measured to validate the effectiveness of the shielding technique. Shielding effectiveness was calculated from the measurements, and their results showed that the isolation between lines was increased by up to 20dB.
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Martins, Jo?mia Leilane Gomes de Medeiros. "An?lise de antenas utilizando substrato cer?mico, zpt, produzido por s?ntese auto propagante para aplica??es em sistemas de micro-ondas." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15230.
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Ceramic substrates have been investigated by researchers around the world and has achieved a high interest in the scientific community, because they had high dielectric constants and excellent performance in the structures employed. Such ceramics result in miniaturized structures with dimensions well reduced and high radiation efficiency. In this work, we have used a new ceramic material called lead zinc titanate in the form of Zn0,8Pb0,2TiO3, capable of being used as a dielectric substrate in the construction of various structures of antennas. The method used in constructing the ceramic combustion synthesis was Self- Sustained High Temperature (SHS - "Self-Propagating High-Temperature Synthesis") which is defined as a process that uses highly exothermic reactions to produce various materials. Once initiated the reaction area in the reaction mixture, the heat generated is sufficient to become self-sustaining combustion in the form of a wave that propagates converting the reaction mixture into the product of interest. Were analyzed aspects of the formation of the composite Zn0,8Pb0,2TiO3 by SHS powders and characterized. The analysis consisted of determining the parameters of the reaction for the formation of the composite, as the ignition temperature and reaction mechanisms. The production of composite Zn0,8Pb0,2TiO3 by SHS performed in the laboratory, was the result of a total control of combustion temperature and after obtaining the powder began the development of ceramics. The product was obtained in the form of regular, alternating layers of porous ceramics and was obtained by uniaxial pressing. 10 The product was characterized by analysis of dilatometry, X-ray diffraction analysis and scanning electron microscopy. One of the contributions typically defined in this work is the development of a new dielectric material, nevertheless presented previously in the literature. Therefore, the structures of the antennas presented in this work consisted of new dielectric ceramics based Zn0,8Pb0,2TiO3 usually used as dielectric substrate. The materials produced were characterized in the microwave range. These are dielectrics with high relative permittivity and low loss tangent. The Ansoft HFSS, commercial program employee, using the finite element method, and was used for analysis of antennas studied in this work
Substratos cer?micos t?m sido investigados por pesquisadores de todo o mundo e tem despertado um grande interesse na comunidade cient?fica, pelo fato de apresentarem altas constantes diel?tricas e um excelente desempenho nas estruturas empregadas. Tais cer?micas resultam em estruturas miniaturizadas, com dimens?es bem reduzidas e de alta efici?ncia de radia??o. Neste trabalho, utilizou-se um novo material cer?mico, chamado de titanato de zinco chumbo, na forma de Zn0,8Pb0,2TiO3, capaz de ser utilizado como substrato diel?trico na constru??o de diversas estruturas de antenas. O m?todo utilizado na constru??o da cer?mica foi a S?ntese por Combust?o Auto-Sustentada a Alta Temperatura (SHS Self-Propagating High-Temperature Synthesis ) que ? definido como um processo que utiliza rea??es altamente exot?rmicas para produzir os mais diversos materiais. Uma vez iniciada a rea??o numa ?rea da mistura reagente, o calor gerado ? suficiente para tornar a combust?o auto-sustent?vel, na forma de uma onda que se propaga convertendo a mistura reagente no produto de interesse. Foram analisados os aspectos da forma??o do comp?sito Zn0,8Pb0,2TiO3 por SHS e os p?s obtidos, foram caracterizados. A an?lise consistiu na determina??o dos par?metros da rea??o para a forma??o do comp?sito, como a temperatura de igni??o e os mecanismos de rea??o. A produ??o do comp?sito Zn0,8Pb0,2TiO3 por SHS, realizada em laborat?rio, foi resultado de um controle total da temperatura de combust?o e ap?s a obten??o do p? 8 iniciou-se o desenvolvimento das cer?micas. O produto foi obtido na forma de camadas regulares e altern?ncia de porosidades e as cer?micas foram obtidas por prensagem uniaxial. O produto foi caracterizado atrav?s de an?lises de dilatometria, difra??o de raios-X e an?lise de microscopia de varredura eletr?nica. Uma das contribui??es principais deste trabalho foi o desenvolvimento de um novo material diel?trico, n?o obstante apresentado anteriormente na literatura. Portanto, as estruturas das antenas apresentadas neste trabalho foram constitu?das por novas cer?micas diel?tricas ? base de Zn0,8Pb0,2TiO3, geralmente utilizado como substrato diel?trico. Os materiais desenvolvidos foram caracterizados na faixa de micro-ondas. S?o substratos diel?tricos de alta permissividade relativa e baixa tangente de perda. O software comercial empregado, Ansoft HFSS, baseado no m?todo dos elementos finitos, foi utilizado na an?lise das antenas estudadas neste trabalho
33
Aalto, Alve, and Ali Jafari. "Automatic Probing System for PCB : Analysis of an automatic probing system for design verification of printed circuit boards." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-174865.
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The purpose of this thesis is to conduct an analysis of whether the printed circuit boards from Ericsson can be tested using an automatic probing system or what changes in the design are required, to be a viable solution. The main instrument used for analyzing the printed circuit board was an oscilloscope. The oscilloscope was used to get the raw data for plotting the difference between the theoretical and actual signals. Connected to the oscilloscope was a 600A-AT probe from LeCroy. The programs used for interpreting the raw data extracted from the oscilloscope included Python, Matlab and Excel. For simulations on how an extra via in the signal path would affect the end results we used HFSS and ADS. The results were extracted into different Excel sheets to get an easier overview of the results. The results showed that the design of a board must almost become completely rebuilt for the changes, and it is therefore better to implement in a new circuit board rather than in an already existing one. Some of the components have to either be smaller or placed on one side of the board, where they cannot be in the way of the probe. The size of the board will become larger since the rules of via placements will be limited compared to before. The most time demanding part was the simulations of the extra via in the signal path, and the results showed that if a single-ended signal is below two gigahertz the placing of the via does not make a big difference, but if the signal has a higher frequency the placement is mostly dependent on the type of the signal. The optimal placement is generally around four millimeters away from the receiving end.Målet med detta examensarbete är att göra en analys av huruvida Ericssons kretskort kan testas med hjälp av ett automatiskt probe system eller om det kräver stora förändringar i designdelen av kretskorten och om, vad för förändringar det i sådant fall kan vara. Till hjälp att analysera kretskorten har vi haft oscilloskop för att få ut rådata om skillnaderna mellan de teoretiska och verkliga signalerna. För att kunna tyda oscilloskopets samplade signaler har olika programmeringsspråk som Python, Matlab samt Excel använts. En extra via i signalens väg har även simulerats i HFSS och ADS med olika sorts probar för att se hur signalens beteende påverkas. Resultaten extraherades sedan in i olika Excel ark för att få en lätt överskådlig bild av resultaten. Resultatet vi fick visade att utformningen av ett kretskort med ändringarna skulle vara lättare att göra med en ny design istället för en redan existerande då större delar av kortet skulle behöva göras om. Vissa stora komponenter behöver antingen göras om, hitta mindre men likvärdiga eller sättas på ena sidan av kortet där de inte är i vägen för proben. Kretskorten som kommer använda flygande probesystem kommer antagligen bli lite större då viornas placering är mer begränsade än tidigare. Det mest tidskrävande arbetet var att simulera olika placeringar av en extra via i signalens väg. Detta visade att på en single ended signal under två gigahertz så gör det ingen större skillnad vart i signalens väg som den extra vian placeras. Då en högre frekvens används så är själva signalens karaktär det viktigaste än placeringen av en via, men om man inte vet den exakta karaktären så är fyra millimeter bort från mottagarens sida att rekommendera då närmare placering av viorna gör att signalerna börjar störa varandra.
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Samuelsson, Jacob. "Phased array antenna element evaluation." Thesis, Linköpings universitet, Fysik och elektroteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-141690.
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This thesis evaluates two array antenna elements for large phased array antennas. The two antenna concepts are a surface mounted notch element and a PIFA (Planar Inverted F Antenna). The antennas have been simulated at S-band in Ansys HFSS as a unit cell in an infinite array environment. Thereafter, a finite 7 x 7 element array of the two concepts was simulated. A corresponding 49 element array, using the notch element, was built and measured upon. Embedded element patterns and S-matrix parameters have been measured. From this result, full array antenna patterns as well as active reflection coefficients have been calculated. The measurements show very good performance for large scan angles and a wide frequency range.
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Ladas, Thomas P. "An Optogenetic Approach to Induce Seizure Suppression." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1389054549.
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Cartier, Camille. "Comportement des terres rares (REE) et des éléments fortement chargés (HSFE) pendant la différenciation précoce de la Terre sous faible fugacité d'oxygène." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22525/document.
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La Terre contient une quantité significative d’eau et son manteau est très oxydé par rapport aux conditions canoniques de la nébuleuse solaire, ce qui est contradictoire avec l’existence de son noyau métallique et sa position dans le Système solaire. Ceci implique que l’état rédox de la Terre ait augmenté au début de son histoire. Aujourd’hui, de nombreuses études suggèrent que cette évolution se soit faite à travers une accrétion hétérogène. Ainsi les premières briques élémentaires de notre planète seraient constituées de matériel très réduit et une grande partie de la différenciation précoce (extraction du noyau et différenciation silicatée) se seraient donc déroulées en conditions très réductrices (entre IW-5.5 et IW-2). L’objectif de cette thèse est de mesurer l’impact de ces conditions sur le comportement des terres rares (REE) et des éléments fortement chargés (HSFE), et de modéliser leur répartition dans les différents réservoirs lors de la différenciation précoce de la Terre. Nous réalisons une soixantaine d’expériences de fusion – cristallisation à l’équilibre de matériel chondritique à basse (5 GPa) et haute (26 GPa) pression, dans une gamme de conditions rédox allant de IW (tampon fer – wüstite) à IW-8. Afin de caractériser le paramètre fO 2 dans ces conditions extrêmes, nous développons un formalisme thermodynamique adapté, basé sur l’équilibre Si-SiO 2 . En analysant les différentes phases à l’équilibre dans les différents échantillons, nous calculons et établissons la première banque de données de partage cristal (enstatite, bridgmanite = pérovskite silicatée, majorite) – liquide silicaté, métal-silicate et sulfure-silicate pour les HFSE et les REE en conditions très réductrices. Grâce aux données enstatite – liquide nous développons un proxy de la fO 2 , basé sur le rapport D(Cr)/D(V) et grâce auquel nous mesurons la fO 2 de chondres de type I comme étant similaires aux conditions canoniques de la nébuleuse (IW-7). Nos données de partage métal – silicate prouvent que l’extraction du noyau terrestre n’est pas à l’origine d’un fractionnement des terres rares. Au contraire, en mesurant pour la première fois le spectre XANES du Nb 2+ et du Ta 3+ dans des verres silicatés à des teneurs de l’ordre du ppm, nous prouvons que le comportement de Nb et Ta est contrôlé par la fO 2 . En intégrant nos données de partage à un modèle d’accrétion hétérogène nous montrons que la signature sous-chondritique en Nb/Ta de la Terre silicatée peut être le résultat de l’accrétion d’un matériel chondritique évoluant avec le temps combinée à l’extraction du noyau en conditions réductrices, ce qui réfute l’hypothèse d’une Terre se formant à partir d’un matériel oxydé. Nos expériences de haute pression montrent que le partage des REE et des HFSE dans la majorite et la bridgmanite est très sensible à la fO 2. De plus, le processus de dismutation du fer, invoqué pour expliquer l’augmentation de la fO 2 du manteau lors de la cristallisation de l’océan magmatique, ne semble pas être un mécanisme efficace en-dessous de IW. Enfin, nos données montrent que Ti, V, Cr, Mn, Nb et Ta sont chalcophiles en conditions très réductrices. L’extraction précoce d’un liquide sulfuré dans ces conditions a donc pu modifier les rapports élémentaires supposés chondritiques dans la Terre silicatée. L’extraction d’une importante quantité de FeS pourrait aussi être à l’origine d’un découplage Zr/HfThe Earth contains significant amounts of water and its mantle is highly oxidized compared to the solar nebula canonical conditions, which is inconsistent with the existence of its metallic core and its location in the Solar System. This implies the redox state of the Earth has increased during its early history as suggested in heterogeneous accretion models. Thus, the first building blocks of our planet would have been made of highly reduced material, and the early Earth’s differentiation (core extraction and silicate differentiation) would have taken place under highly reducing conditions (between IW-5.5 and IW-2). The aim of this thesis is to measure the impact of these conditions on rare earth elements (REE) and high field strength elements (HFSE) behavior, and model their distribution into the main reservoirs formed early in Earth’s history. We run about sixteen melting – crystallization experiments, starting from chondritic material and equilibrating it at low (5 GPa) and high (26 GPa) pressure, spanning a redox range going from IW (iron – wüstite buffer) to IW-8. In order to characterize the fO 2 parameter in these extreme conditions, we develop an adapted thermodynamic formalism, based on Si-SiO 2 equilibrium. Analyzing the various equilibrated phases within our experimental samples, we calculate and propose the first crystal (enstatite, bridgmanite = Mg-perovskite, majorite) – silicate liquid, metal – silicate, sulfide – silicate partition coefficients database for HFSE and REE under highly reducing conditions. Using our enstatite-liquid data we develop a fO 2 proxy based on D(Cr)/D(V) ratio and we measure type I chondrule fO 2 as being similar to canonical nebular conditions (IW-7). Our metal-silicate partitioning data prove that Earth core extraction is not responsible for REE fractionation. On the contrary, recording for the first time Nb 2+ and Ta 3+ XANES spectra in silicate glasses and at ppm level concentrations, we prove that Nb and Ta behavior is mainly controlled by fO 2 . Using our partitioning data in a heterogeneous accretion model, we show that sub-chondritic Nb/Ta signature of the silicate Earth (14 ± 0.3) can be the result of the accretion of chondritic material changing with time, combined with the progressive extraction of the core in reducing conditions. This refutes the hypothesis of an oxidized material building the Earth. Our high-pressure experiments show that REE and HFSE partitioning in majorite and bridgmanite is very sensitive to fO 2 . Moreover, iron dismutation process, invoked to explain mantle fO 2 increase during magma ocean crystallization, does not seem to be an efficient mechanism below IW. Finally, our data show that Ti, V, Cr, Mn, Nb and Ta are chalcophiles under highly reducing conditions. Consequently, early extraction of a sulfide melt at an early and reduced stage could have modified chondritic elementary ratios in the silicate Earth. Extraction of a substantial amount of FeS may also cause a Zr/Hf decoupling
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Santos, Rafael Celestino dos. "Estudo da interfer?ncia de uma metasuperf?cie no desempenho das antenas de microfita." PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA EL?TRICA E DE COMPUTA??O, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/22396.
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Este trabalho tem por objetivo apresentar a influ?ncia de uma metasuperf?cie, um tipo especial dos metamateriais, no desempenho das antenas de microfitas. As metasuperf?cies s?o materiais artificiais que n?o s?o encontrados em sua forma convencional na natureza e apresentam caracter?sticas eletromagn?ticas n?o convencionais, como o ?ndice de refra??o e os coeficientes de permissividade el?trica e permeabilidade magn?tica negativos o que provocam efeitos eletromagn?ticos atrativos para diversas aplica??es, como por exemplo: melhorar a performance de uma antena de microfita como ser? mostrado nesse trabalho. Iniciaremos o trabalho mostrando um breve hist?rico, defini??es e propriedades eletromagn?ticas das antenas, antenas de microfita, metamateriais e das metasuperf?cies. Em seguida, iremos projetar e confeccionar uma antena de microfita com e sem a utiliza??o de uma metasuperf?cie onde simularemos atrav?s do software HFSS Ansoft Designer e testaremos em laborat?rio atrav?s do equipamento E5071C ENA Network Analyzer. Por fim, realizaremos uma an?lise comparativa, mostrando o quanto a metasuperf?cie melhora a performance de uma antena de microfita atrav?s de uma an?lise dos diversos par?metros da antena, como: perda de retorno, ganho de pot?ncia, diretividade e imped?ncia de entrada.
This paper aims to present the influence of a metasurface, a special type of metamaterials, in the performace of microstrip antennas. The metasurface are artificial materials that are not found in a conventional manner in nature and do not have conventional electromagnetic characteristics such as refractive index and coefficient of permittivity and negative magnetic permeability which causes attractive electromagnetic effects for various applications, such as: improving the performance of a microstrip antenna as will be shown in this work. We started the work showing a brief history, definitions and electromagnetic properties of the antennas, microstrip antennas, metamaterials and metasuperf?cies. Next, we will design and manufacture a microstrip antenna with and without the use of a metasurface where we will simulate through HFSS Ansoft Designer software and test in the laboratory with the E5071C ENA Network Analyzer. Finally, we will perform a comparative analysis, showing how the metasurface improves the performance of a microstrip antenna by analysis of the various parameters antenna, such as: return loss, power gain, directivity and input impedance.
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Yasar, Orten Pinar. "Numerical Analysis, Design And Two Port Equivalent Circuit Models For Split Ring Resonator Arrays." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611620/index.pdf.
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Split ring resonator (SRR) is a metamaterial structure which displays negative permeability values over a relatively small bandwidth around its magnetic resonance frequency. Unit SRR cells and arrays have been used in various novel applications including the design of miniaturized microwave devices and antennas. When the SRR arrays are combined with the arrays of conducting wires, left handed materials can be constructed with the unusual property of having negative valued effective refractive indices.
In this thesis, unit cells and arrays of single-ring multiple-split type SRR structures are numerically analyzed by using Ansoft&rsquos HFSS software that is based on the finite elements method (FEM). Some of these structures are constructed over low-loss dielectric substrates and their complex scattering parameters are measured to verify the numerical simulation results. The major purpose of this study has been to establish equivalent circuit models to estimate the behavior of SRR structures in a simple and computationally efficient manner. For this purpose, individual single ring SRR cells with multiple splits are modeled by appropriate two-port RLC resonant circuits paying special attention to conductor and dielectric loss effects. Results obtained from these models are compared with the results of HFSS simulations which use either PEC/PMC (perfect electric conductor/perfect magnetic conductor) type or perfectly matched layer (PML) type boundary conditions. Interactions between the elements of SRR arrays such as the mutual inductance and capacitance effects as well as additional dielectric losses are also modeled by proper two-port equivalent circuits to describe the overall array behavior and to compute the associated transmission spectrum by simple MATLAB codes. Results of numerical HFSS simulations, equivalent circuit model computations and measurements are shown to be in good agreement.
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Mizera, Josef. "Podpora kvalitativních požadavků služeb v operačních systémech unixového typu pro provoz v bezdrátových sítích WiFi." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220637.
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Diploma thesis is focused on the supporting of Quality of Services in wireless networks, especially in the Linux operation systems. The topic is connected not only with OS, but also with the wireless standard, which supports QoS in wireless networks called IEEE 802.11e. QoS is needed especially for time-consuming data transfers in real time. The theoretical part deals with the theoretical analysis of the issue of the QoS support. There are described parameters, which occurred in quality of services support. This section also deals with the division of services that are used to transmit data across computer networks. It also describes the QoS support in wireless networks according 802.11e, its implementation and methods of accessing a medium with a without possibility of traffic. This part is followed by a description of QoS support in UNIX operating systems. The chapter describes how is the QoS support designed in these operating systems. There are also characterized concrete tools which are used for control the data flow in the operating systems using Linux. At the end the theoretical part deals with different types of queues and methods used in linux OS. In the practical part of the thesis, there are various designed topologies and scenarios to verify the functionality of QoS support in wireless networks using a Unix system. These chapters show the results of different tests at selected transmission data streams that are sensitive to transmission time. There is also verified cooperation of QoS support between devices operating on the network and data link layers. The output of this work is to design a laboratory exercise for the subject Network Architecture. This exercise is focused on familiarization with the QoS support functionality in wireless networks and in Unix-like operating systems. This chapter also describes the devices and programs that are needed to measure this task. The last part of the chapter describes the procedure for the preparation of the measuring station. For this laboratory task, there is an inserted manual in the annex.
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Eriksson, Lina, and Rebecca Hansson. "Arbete med livsstilsfrågor och livsstilsformulär vid ett hälsofrämjande sjukhus." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-154244.
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Syfte: Att undersöka hur läkare och sjuksköterskor arbetar med livsstilsfrågor och livsstilsfor-muläret vid lasarettet i Enköping. Dessutom undersöka vad personalen har för åsikt omlivsstilsformuläret samt om de behöver mer kunskap om livsstilsfrågorna och motiverandesamtal. Metod: En enkät skickades ut till 79 sjuksköterskor och läkare, svarsfrekvens 52 %.Huvudresultat: Alla deltagare tyckte att det var mycket viktigt eller ganska viktigt att frågapatienter om livsstilsfrågor och de områden man frågade mest om var tobak och alkohol.Bland svaren framkom det att de flesta samtalade med en patient som hade ett riskbeteende.De områden deltagarna ville ha mest kunskap i var motiverande samtal och stress. Positivaåsikter som framkom om livsstilsformuläret var att personalen fick en bra överblick av patien-tens levnadsvanor och hade ett bra underlag att samtala om vid mötet med patienten. De nega-tiva aspekterna som framkom var formulärets utformning och svarsalternativ som ansågs varaför komplicerat. Slutsats: Det hälsofrämjande arbetet anses viktigt och det behövs kontin-uerlig utbildning till personalen för att kunna arbeta med dessa frågor med patienterna. Detbehövs även klarare riktlinjer i uppföljningen av patienter med riskbeteende. Livsstilsfor-muläret är ett bra verktyg men det behöver förbättras.Aim: To study how physicians and nurses work with health promotion at the hospital inEnköping, Sweden. And investigate the staffs’ opinion about the lifestyle questionnaire and ifthey need more education in health promotion or motivational interviewing. Method: Aninquiry was sent to 79 nurses and doctors, with a response rate of 52 %. Primary results:Everyone thought it was important or very important to ask about lifestyle questions werealcohol and tobacco was the most frequently asked questions. Among the answers most ofthem had a conversation with patients who had a risk behavior. The subjects that the staffwanted more knowledge of was motivational interviewing and stress. The positive aspects ofthe questionnaire were that the employees got an overview of the patient ́s health and couldhave a conversation around it. The negative aspect of the questionnaire was the formattingand the complicated answers to choose from. Conclusion: The work with health promotion isimportant and the employees need a continuously updated education to work in a professionalway with the patients. There is also a need to have stricter routines to evaluate the patientswith a risk behavior. The questionnaire is a good tool to work with but it needs improvement.Keywords: Health promoting hospitals (HPH), employees, lifestyle questions, questionnaireof lifestyle.
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Wade, Massar. "Evaluation de condensateurs enterrés à base de composites céramique/polymère pour des applications à hautes fréquences." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0156/document.
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La miniaturisation croissante des systèmes électroniques implique de réduire la taille des composants électroniques, en particulier des composants passifs (condensateurs, résistances et inductances), notamment les condensateurs, volumineux et de surcroît nombreux. Pour répondre à cette attente, une des options est d’intégrer « enterrer » les couches capacitives dans le circuit imprimé à base de matériaux composites céramique/polymère. Dans un premier temps, plusieurs types de matériaux composites à base de nanoparticules de céramique (BaTiO3 et BaSrTiO3) et de polyester pour des condensateurs enterrés sont développés. Ensuite, la permittivité ε’ et les pertes diélectriques des composites sont évaluées dans les gammes de fréquences entre [10 kHz – 10 MHz] et [1 GHz – 5 GHz]. En vue d’intégrer ces composants à l’intérieur du circuit imprimé parfois souple et flexible, le comportement piézoélectrique des composites est évalué. La mesure du courant de fuite permettant d’effectuer une analyse qualitative des matériaux composites a été également effectuée.Au niveau de l’étude des condensateurs enterrés dans le circuit imprimé, deux structures de tests ont été réalisées : l’une montée en parallèle et l’autre en série. L’étude est réalisée sur deux gammes de condensateurs. La première est à base de matériau composite stable en fréquence et la seconde varie avec la fréquence. Pour cela, une méthode originale qui permet d’extraire la variation de la permittivité εr (f) à haute fréquence a été développée. La méthode se repose principalement sur l’utilisation des résultats de mesure de la permittivité relative du condensateur en basse fréquence, et les résultats de la valeur de la fréquence de résonance obtenue en simulation électromagnétique.Enfin, pour améliorer la fréquence de fonctionnement des condensateurs enterrés, des règles de conception permettant de comprendre l’influence des vias de connexions et de la géométrie des électrodes sur la fréquence de résonance du dispositif de test sont étudiéesThe increasing miniaturization of electronic systems involves reducing the size of electronic components, in particular passive components (capacitors, resistors and inductors), including capacitors, large and many more. To meet this expectation, one of the options is to integrate "bury" the capacitive layers based on ceramic / polymer composites in the PCB. In a first step, several types of composite materials based on nanoparticle ceramic (BaTiO3 and BaSrTiO3) and polyester for buried capacitors are developed. Then, the permittivity ε' and the dielectric losses of the composites are measured in the ranges of frequencies between [10 kHz - 10 MHz] and [1 GHz - 5 GHz]. To integrate these components within the PCBs sometimes soft and flexible, the piezoelectric behavior of composites is evaluated. The measurement of leakage current to perform a qualitative analysis of composite materials was also made.At the level of the study of buried capacitors in the circuit board, two test structures were carried out: one mounted in parallel and the other in serial. The study is produced in two ranges of capacitors. The study is conducted on two capacitors ranges. The first case, the relative permittivity does not depend on the frequency while in the second case the frequency dependence is taken into account. For this, an original method which allows to extract the permittivity εr(f) variation in high-frequency was developed. The method is mainly based on the use of measurement results of the relative permittivity of low-frequency capacitor, and the results of resonance frequency value obtained by 3D HFSS electromagnetic simulation. Finally, to improve the operating frequency of the buried capacitors, design rules allowing understand the influence of the vias and geometry of electrodes on the resonant frequency of the structures are studied
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Júnior, João Alves Cardoso. "Aspectos clínicos, demográficos e neurocomportamentais em pacientes com espasmo hemifacial." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17161/tde-28112018-101408/.
Full textAbstract:
O espasmo hemifacial (EHF) é um distúrbio de movimento caracterizado por contrações tônico ou clônicas involuntárias, unilaterais, intermitentes e irregulares dos músculos inervados pelo nervo facial ipsilateral. Apesar de considerado como um transtorno benígno, promove influência significativa na qualidade de vida dos portadores através do comprometimento funcional físico e emocional que promove, englobando, desde o prejuízo na leitura e outras funções visuais, até o constrangimento social e distúrbios psiquiátricos associados, como depressão e ansiedade. Objetivo.: Descrever as características clínicas e demográficas, assim como a frequência de sintomas psiquiátricos de ansiedade generalizada, social e depressão, e a relação destes sintomas com a qualidade de vida nesta amostra de pacientes. Métodos.: 111 pacientes portadores de EHF primário foram avaliados. Foi aplicado questionário geral para coleta de dados demográficos e clínicos associados a evolução e tratamento do distúrbio de movimento com toxina botulínica. Os sintomas psiquiátricos foram avaliados através de escalas validadas para a população brasileira. A avaliação de qualidade de vida foi através de escala específica validada para avaliação funcional nos portadores de EHF. Resultados.: A idade média de início foi de 49±13,1 (intervalo: 12 -77) e tempo de evolução até o diagnóstico de 3±1,5 anos, com predomínio no sexo feminino (2,08:1). O lado esquerdo foi afetado em 61 (54,9%) pacientes e o músculo orbicular dos olhos foi o primeiro acometido na maioria dos casos (85,5%). Grande parte (n=87) referiu início insidioso e evolução gradual. Nervosismo, estresse e ansiedade são importantes contribuintes de piora do espasmo, relatado por mais de 82% (n=92) dos portadores de EHF, e momentos de relaxamento, tranquilidade, descanso e atividades de lazer foram responsáveis por aliviar o espasmo em 57 entrevistados. Mais de 90% (n=96) perceberam melhora importante do espasmo após aplicação de TXB, e 24,5% (n=26) relataram algum efeito adverso em última aplicação, sendo assimetria labial e ressecamento ocular os mais frequentes. Sobre os sintomas psiquiátricos, 41,7% (n=45) apresentavam pontuações que sugerem algum grau de depressão, até 56,4% (n=57) ansiedade generalizada e 34,2% (n=38) ansiedade ou fobia social. A leitura como domínio funcional físico e a vergonha, a tristeza e a preocupação com reação de outras pessoas foram os maiores prejuízos funcionais descritos nesses pacientes. Conclusão.: As características clínicas e demográficas nos pacientes com EHF se assemelham a outras evidências descritas na literatura, assim como uma maior frequência de sintomas de depressão, ansiedade generalizada e fobia social nesta população. Os sintomas psiquiátricos, mais do que a gravidade do espasmo, apresentaram uma maior correlação com a qualidade de vida nesta amostra de pacientes.Hemifacial spasm (HFS) is a movement disorder characterized by involuntary, unilateral, intermittent, tonic or clonic contractions of muscles innervated by the ipsilateral facial nerve. Although considered as a benign disorder, it promotes a significant influence on the quality of life of the patients through the physical and emotional impairment it promotes, ranging from impairment in reading and other visual functions to social embarrassment, and associated psychiatric disorders, such as depression and anxiety. Objective.: To describe the clinical and demographic characteristics, as well as the frequency of psychiatric symptoms of generalized anxiety, social anxiety and depression, and the relation of these symptoms with quality of life in this sample of patients. Methods.: 111 patients with primary HFS were evaluated. A general questionnaire was used to collect demographic and clinical data associated with the evolution and treatment of the movement disorder with botulinum toxin (BTX). The psychiatric symptoms were evaluated through scales validated for the Brazilian population. The quality of life assessment was based on a specific validated scale for functional evaluation in patients with HFS. Results.: The mean age at onset was 49 ± 13.1 (range: 12-77) and time to diagnosis of 3 ± 1.5 years, with a predominance of females (2.08 :1). The left side was affected in 61 (54.9%) patients and the orbicularis oculi muscles were the first affected in the majority of cases (85.5%). A large part (n = 87) reported insidious onset and gradual evolution. Nervousness, stress, and anxiety are important contributors to worsening spasm, reported by more than 82% (n = 92) of HFS patients, and moments of relaxation, tranquility, rest, and leisure activities were responsible for relieving spasm in 57 interviewees. More than 90% (n = 96) reported significant improvement of spasm after BTX application, and 24.5% (n = 26) reported some adverse effects in the last application, with lip asymmetry and ocular dryness being the most frequent. On the psychiatric symptoms, 41,7% (n = 45) presented scores that suggest some degree of depression, up to 56.4% (n = 57) generalized anxiety and 34.2% (n = 38) anxiety or social phobia. Reading as a physical functional domain and shame, sadness and concern for other people\'s reactions were the major functional losses described in these patients
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Estrade, Guillaume. "Le complexe cénozoïque alcalin d'Ambohimirahavavy à Madagascar : origine, évolution et minéralisations en métaux rares." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2583/.
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Ce travail a pour objectif l'étude de la géologie du complexe annulaire alcalin d'Ambohimirahavavy, au nord-ouest de Madagascar, en mettant l'accent sur la compréhension des phénomènes à l'origine de la formation des minéralisations à métaux rares (Zr, Hf, Nb, Ta, Th, U et terres rares). Le complexe, mis en place à la limite oligo-miocène, serait issu de la différenciation magmatique d'un magma parent d'origine mantellique. En fin d'évolution, des phénomènes de contamination crustale expliqueraient l'association des séries magmatiques sous- et sursaturées en silice dans le complexe. Les termes les plus différenciés de ces deux séries évolueraient vers des compositions hyperalcalines dans des conditions de fugacité en oxygène opposées. La minéralisation à métaux rares est essentiellement associée aux roches des faciès sursaturés, à savoir, des filons de granite et de pegmatite hyperalcalins. Deux types essentiels de minéralisation ont été reconnus, une miaskitique caractérisée par la présence de plusieurs types de zircon et une agpaïtique riche en eudialyte. La formation de ces minéralisations serait liée à la fois à des processus magmatiques et hydrothermaux. Les granites et les pegmatites riches en métaux rares se formeraient à partir de magmas hyperalcalins enrichis à l'extrême en éléments fluants (F, Cl); la minéralisation est alors représentée par un zirconosilicate riche en métaux rares, l'eudialyte. Les fluants vont diminuer considérablement la température du solidus et augmenter la solubilité de l'eau dans le magma. En fin de cristallisation, on pourra avoir des phénomènes de démixtions de fluides orthomagmatiques riches en Na, Si, F et Cl à l'origine des pseudomorphoses de l'eudialyte en zircon et des néoformations de minéraux à métaux rares. Des datations U-Pb sont en accord avec la formation de ces zircons à partir d'un fluide, donnant des âges autour de 21 Ma, soit 3 Ma plus jeunes que la mise en place des syénites à néphéline, datées également par la méthode U-Pb sur zircon. Cette étude montre également que la composition de l'encaissant peut jouer un rôle essentiel en forçant la précipitation des minéraux à métaux rares dans des formations de type skarn, dans laquelle interviennent aussi des fluides météoriques. Ce travail met en évidence la complexité des processus d'enrichissement et de fractionnement des métaux rares depuis le magma parent d'origine mantellique aux faciès évolués pegmatitiques conduisant à la diversité des minéralisations rencontrées dans ces roches hyperalcalines. Enfin, cette étude propose également une nouvelle cible potentielle de minéralisation en relation avec les faciès sous-saturésThis thesis focuses on the Oligo-Miocene Ambohimirahavavy alkaline complex, in Northwestern Madagascar. Its objective is to investigate the formation of this complex, in particular, to understand the formation of the associated rare-metal mineralization (Zr, Nb, Ta, Th, U and the rare earth elements). It will be shown that the complex formed through magmatic differentiation of mantle-derived magmas that, upon ascent, evolved to SiO2 undersaturated and SiO2 oversaturated varieties by crustal contamination. Finally, a strongly peralkaline composition evolved from the most differentiated magma, at oxygen fugacity conditions opposite from those recorded for the less differentiated units. The rare-metal mineralization is mainly associated with the oversaturated rocks, i. E. , the peralkaline granites and pegmatite dykes. Two main types of mineralization could be identified, one, miaskitic, characterized by several generations of zircon, and one, agpaitic, consisting mainly of eudialyte. Both types of mineralization formed from a combination of magmatic and hydrothermal processes. An early enrichment stage took place by primary magmatic processes, mainly due to extreme differentiation which led to the formation of volatile-rich peralkaline granitic melts. The rare metals deposited during this stage were remobilized and redistributed during hydrothermal alteration caused by orthomagmatic fluids. These exsolved during the final stages of crystallization, caused extensive pseudomorphism of primary rare-metals bearing minerals and redistributed the rare metals within the intrusives as well as in the host rock, mostly in the form of skarn-like mineralization, which partly involved also meteoric fluids. U-Pb dating of secondary zircons shows ages 3 Ma younger than those obtained by the same method on the syenites, confirming the hydrothermal origin of the zircons. This study highlights the complex processes involved in the formation of peralkaline granites and pegmatites and the diversity of mineralization types associated with these rocks. The proposed model can be used as an exploration tool and can help determining potential drilling targets in the undersaturated units of the complex
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Lecián, Petr. "Ozařovač parabolické antény v pásmu X." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218634.
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The work addresses the unusual proposal feed for parabolic antenna with circular polariza-tion signal. This is a modified waveguide feed, waveguide polarizer with a septum. Contemporary RHCP and LHCP wave occurs in several applications of microwave commu-nication and measurement system. From this point of view the septum polarizer can be useful. The septum polarizer is a four-port waveguide device. The square waveguide at one end con-stitutes two ports because it can support two orthogonal modes. A stepped septum divides the square waveguide into two standard rectangular waveguides sharing a common broad-wall. The size of the septum as well as two versions of the waveguides excitation were analyzed and are described in this paper. Ansoft HFSS is software for design and simulation of feed. This software can visualize not only the specified model feed, but also the course of electromagnetic field in feed and over time.
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Sedlář, Petr. "Návrh a realizace klecové cívky pro MRI." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242001.
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The work deals with the design and experimental production of the model type Birdcage coil used for magnetic resonance imaging system (MRI). The work deals with the design and behaviour of the model type Birdcage coil volume designed for imaging system for magnetic resonance imaging (MRI). Volume coils are generally very useful for use in MRI, because in transversal design allow easy access into the cavity when the flow vector of magnetization. The aim of the work was to construct a numerical model of transversal coil type Birdcage of the predefined dimensions. The created the coil tuned the desired resonant frequency having regard to maximize performance in the measured sample migrated. The modeling coil experimentally produced and measurements also confirm the accuracy of the numerical model.
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Gama, Sophie. "Evénements métallogéniques à W-Bi (Au) à 305 Ma en Châtaigneraie du Cantal : apport d'une analyse multi-spectrométrique (micro PIXE-PIGE et Raman) des minéraux et des fluides occlus à l'identification des sources de fluides hydrothermaux." Phd thesis, Université d'Orléans, 2000. http://tel.archives-ouvertes.fr/tel-00002404.
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Le district de la Châtaigneraie comporte deux mines de W de type filonien encaissées dans les micaschistes au contact des granites. Afin de contraindre la source de ces minéralisations, des analyses ponctuelles d'éléments traces dans des inclusions fluides et minéraux de la paragenèse minéralisée primaire ont été entreprises par PIXE-PIGE et comparées aux analyses des minéraux et des fluides des réservoirs métamorphique et leucogranitique, sources potentielles des métaux.L'emploi d'un "funny filter" lors de l'analyse PIXE permet la détection des éléments K à U. Ce travail illustre que cette méthode est absolue à condition que la géométrie du dispositif analytique soit connue précisément. La paragenèse primaire à W possède une signature d'éléments traces d'affinité leucogranitique (F, Mn, Zn, Ga, As, Nb, Sn, Ta, W, Bi). L'arsenic apparaît écouplé des leucogranites et contrôlé par les micaschistes encaissants : cet élément est détecté dans les fluides du métamorphisme barrovien (¡Ö340 Ma) et les minéraux et fluides du stade à W (¡Ö305 Ma). Les caisses filoniennes subissent une fracturation en tension, une intense dissolution du quartz, un dépôt géodique
de pyrite et muscovite, une paragenèse à bismuth natif, bismuthinite, molybdénite, chalcopyrite, covellite, tennantite, waylandite, cannonite, sidérite et chlorite. Des tourmalinites massives stériles se développent, en veines ou en remplacement, de façon contemporaine. Les tourmalinites de La Granière présentent du quartz cataclastique avec de nombreuses microinclusions de biotite, muscovite, feldspath potassique, ilménite, zircon, monazite et xénotime. Le cortège de traces de ce stade est caractérisé par Fe, Mn, Cu, Zn, Ti, Cr, Sc, V, Se, Zr, Ag, Cd, Ba, Sr, Sb, Hf, Y, La, Ce et Th.
Les fluides associés sont aquo-carboniques, riches en K, Ca, métaux de base. Le caractère de ce fluide, alumino-potassique, sous-saturé en silice, phosphaté, chargé en métaux lourds et de transition (y compris Cr et Sc), REE, LILE et HFSE, suggère une affinité avec des fluides métasomatiques du manteau, ce que confirment la géochimie, la minéralogie et la texture d'un lamprophyre sécant sur une veine minéralisée. La chimie des minéraux et des fluides indique une ébullition généralisée des
solutions à ce stade en liaison avec le flux thermique élevé et la remontée rapide du bâti en fin d'orogenèse.
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Boissonnas, Daniel Camenzind Philipp. "Rolle des Selbstwerts und der Zufriedenheit in Bezug auf die Arbeitsmarktfähigkeit von Absolventinnen und Absolventen einer Anlehre oder einer zweijährigen beruflichen Grundbildung mit eidgenössischem Berufsattest EBA : Teilstudie aus dem HfH Forschungsprojekt B.5: Arbeitsmarktfähigkeit von Absolventinnen und Absolventen der zweijährigen beruflichen Grundbildung mit eidgenössischem Berufsattest /." Zürich : Hochschule für Heilpädagogik, 2009. http://www.bscw-hfh.ch/pub/bscw.cgi/d4344899/BoissonnasCamenzindAbstract.pdf.
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Fikar, Jan. "Tkané antény." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221314.
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The thesis is aimed to design textile antennas that can operate in the ISM band 5.8 GHz. Attention is turned to practical exploitation of these antennas under regular conditions. Variations of the bandwidth of the antenna due to washing and waterproofing will be observed. Finally, the impact of the proximity of living tissue on the parameters of antennas will be studied.
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Horn, Jacqueline Marie. "Design of a Wearable Flexible Resonant Body Temperature Sensor with Inkjet-Printing." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703340/.
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A wearable body temperature sensor would allow for early detection of fever or infection, as well as frequent and accurate hassle-free recording. This thesis explores the design of a body-temperature-sensing device inkjet-printed on a flexible substrate. All structures were first modeled by first-principles, theoretical calculations, and then simulated in HFSS. A variety of planar square inductor geometries were studied before selecting an optimal design. The designs were fabricated using multiple techniques and compared to the simulation results. It was determined that inductance must be carefully measured and documented to ensure good functionality. The same is true for parallel-plate and interdigitated capacitors. While inductance remains relatively constant with temperature, the capacitance of the device with a temperature-sensitive dielectric layer will result in a shift in the resonant frequency as environmental or ambient temperature changes. This resonant frequency can be wirelessly detected, with no battery required for the sensing device, from which the temperature can be deduced. From this work, the optimized version of the design comprises of conductive silver in with a temperature-sensitive graphene oxide layer, intended for inkjet-printing on flexible polyimide substrates. Graphene oxide demonstrates a high dielectric permittivity with good sensing capabilities and high accuracy. This work pushes the state-of-the-art in applying these novel materials and techniques to enable flexible body temperature sensors for future biomedical applications.
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Crozet, Marielle. "Etudes des interactions hyperfines des 13C par RPE pulsée et RMN à haute résolution en solide sur des complexes à 4Fe et 4S, modèles de sites actifs de métalloprotéines." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10193.
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Ce travail se situe dans le cadre de l'etude des proprietes magnetiques de sites actifs de metalloproteines constitues de quatre atomes de fer et de quatre atomes de soufre. Les etudes par eseem-ft sur monocristaux ainsi que de rmn du #1#3c a l'etat solide developpees dans ce travail, presentent l'avantage de fournir des informations precises sur l'etat de spin et/ou la localisation de la densite de spin au sein du cubane a 4 fe et 4 s. Precedemment, c'etaient les protons des composes modeles etudies qui servaient de sondes pour la determination de la densite de spin grace a des etudes d'endor. Le choix a ete fait ici d'utiliser les atomes de carbone proches du centre paramagnetique et moins nombreux que les protons. Ce travail a donc ete d'etudier par eseem-ft puis par rmn du #1#3c a l'etat solide un complexe modele enrichi en #1#3c soit fe#4s#4(s#1#3ch#2ph)#4