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A high gain multiband offset MIMO antenna based on a planar log-periodic array for Ku/K-band applicationsFakharian, M.M., Alibakhshikenari, M., See, C.H., Abd-Alhameed, Raed 27 March 2022 (has links)
Yes / An offset quad-element, two-port, high-gain, and multiband multiple-input multiple-output (MIMO) planar antenna based on a log-periodic dipole array (LPDA) for Ku/K-band wireless communications is proposed, in this paper. A single element antenna has been designed starting from Carrel's theory and then optimized with a 50-Ω microstrip feed-line with two orthogonal branches that results mainly in a broadside radiation pattern and improves diversity parameters. For experimental confirmation, the designed structure is printed on an RT-5880 substrate with a thickness of 1.57 mm. The total substrate dimensions of the MIMO antenna are 55 × 45 mm2. According to the measured results, the designed structure is capable of working at 1.3% (12.82-12.98 GHz), 3.1% (13.54-13.96 GHz), 2.3% (14.81-15.15 GHz), 4.5% (17.7-18.52 GHz), and 4.6% (21.1-22.1 GHz) frequency bands. Additionally, the proposed MIMO antenna attains a peak gain of 4.2-10.7 dBi with maximum element isolation of 23.5 dB, without the use of any decoupling structure. Furthermore, the analysis of MIMO performance metrics such as the envelope correlation coefficient (ECC) and mean effective gain (MEG) validates good characteristics, and field correlation performance over the operating band. The proposed design is an appropriate option for multiband MIMO applications for various wireless systems in Ku/K-bands.
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Techniques de conception d'oscillateurs contrôlés en tension à très faible bruit de phase en bande Ku intégrés sur silicium en technologie BiCMOS / Design techniques of Ku-band fully integrated Voltage Controlled Oscillators for very low phase noise on silicon in 0.25 µm BiCMOS technologyHyvert, Jérémy 22 September 2016 (has links)
L'objectif de cette thèse est de démontrer la faisabilité d'oscillateurs contrôlés en tension (O.C.T.) rivalisant en termes de bruit de phase avec les O.C.T. fabriqués en technologies III V. Cet O.C.T. doit être complètement intégré, adresser la bande Ku et utiliser la technologie QUBiC4X de NXP Semiconductors. Les travaux de cette thèse sont articulés autour de trois chapitres principaux, le premier revient sur les bases fondamentales à la compréhension des phénomènes inhérents aux composants électroniques et présents dans les oscillateurs plus particulièrement. Le second explique, en s'appuyant sur l'analyse des formes d'ondes et sur des calculs analytiques, les choix retenus en termes d'architecture pour la partie active ainsi que pour le résonateur afin de minimiser la conversion du bruit AM/PM et atteindre les meilleures performances possibles en bruit de phase. Il décrit les quatre versions d'O.C.T. réalisés et analyse les résultats de simulations post-layout obtenus pour justifier leur fabrication. Il présente notamment une architecture innovante utilisant les avantages d'un montage cascode ainsi qu'un résonateur à trois inductances différentielles imbriquées les unes dans les autres. Le troisième chapitre détaille les choix de design faits lors du dessin des masques ainsi que les résultats de mesures obtenus pour les quatre versions fabriquées. Enfin, il se termine par une énumération des recherches menées dans le but d'expliquer les différences observées entre les résultats de mesure et de simulation. / The thesis goal is to demonstrate the feasibility of voltage controlled oscillator (VCO) challenging the VCOs using III-V technologies regarding phase noise performances. This VCO must be fully integrated, target the Ku-band and use the QUBiC4X process from NXP Semiconductors. This thesis work is based on three main chapters, the first one reviews the fundamentals to understand the intrinsic phenomena in electronics components and more particularly in oscillators. The second explains, by using the waveforms analysis and analytical demonstrations, the choices made regarding both the active part and the resonator architecture in order to minimize the AM/PM noise conversion and then to reach the best phase noise performances. It describes the four versions of the realized VCOs and analyzes the post-layout simulations results to justify their fabrications. It shows more specifically an innovative architecture using the advantages of a cascode configuration and a resonator based on three interlocked differential inductors. Finally, the third chapter focuses on the masks' layout and measurements results of the four VCOs. It also details the investigations made to explain the differences between measurements and simulations.
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Analýza motivu kosmického vejce ve stvořitelských mýtech / Analysis of a cosmic egg motif in creation mythsTvrdá, Pavlína January 2015 (has links)
The aim of this thesis is to compare similar cosmogonic narratives in Indian and Chinese culture. The most important elements are the motives of the egg and the giant/god who is formed from it. Comparative method consist of the comparison of the meanings and interpretations of the motives of these two elements, depending on the expectations and character of the source of this mythological narrative. Final findings are, that the importance of both motives in the texts and their participation in the process of creation of the world change chronologically, due to changes in religious, philosophical and social preferences. In Indian cultural environment in the begining, the vague motive of the egg slowly emerges and becomes a single creative element, gaining importance and continues to the stage where it reaches the same level of importance as the cosmic being. The primordial being on the other hand, loses its function of cosmic matter and passes it to the egg. The being itself then plays an active role rather than an object. China, for its religious scepticism suppressed motive of the egg until it was completely removed from texts. The primary role is played by the cosmic giant whose role is not focused on the creation of the world itself but the desintegration of the giants body, representing fission...
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Etude structurale et fonctionnelle des complexes multi-protéiques de la voie de réparation NHEJ chez l’homme / Structural and fonctional analysis of humain nhej pathway multiprotein complexesAmram, Jérémy 02 July 2015 (has links)
La voie de réparation NHEJ (Non-Homologous End-Joining) est une voie majeure de réparation des cassures double-brin chez l’homme. Les protéines de cette voie interagissent et forment des complexes dynamiques dont les mécanismes moléculaires sont encore largement méconnus. Nous avons dans un premier temps mis au point des protocoles de production à l’échelle de plusieurs milligrammes des protéines cœur de la voie NHEJ en cellules d’insecte à l’aide du système MultiBac. Nous avons ainsi purifié les complexes Ku70/Ku80 et Ligase4/XRCC4 et les protéines Cernunnos et Artemis à homogénéité. Des essais de cristallisation, des études par SAXS et des analyses par microscopie électronique ont été réalisés sur différents complexes formés par ces protéines cœur du NHEJ. Nous avons également caractérisé par chromatographie d’exclusion de taille et calorimétrie, les interactions effectuées entre les protéines de la voie NHEJ. L’ensemble de ces travaux a permis d’établir des bases biochimiques solides en vue des études structurales et fonctionnelles de la voie NHEJ chez l’homme. / Human DNA repair pathway NHEJ (Non-Homologous End-Joining) is a major pathway of double-strand breaks repair. The proteins involved in this pathway interact and form dynamic complexes whose molecular mechanisms are largely unknown. Firstly, we established protocols to be able to purify milligrams of those NHEJ pathway core proteins using MultiBac insect cells system. We then purified Ku70/Ku80 and Ligase4/XRCC4 complexes, Artemis and Cernunnos to homogeneity. Crystallogenesis assays, SAXS experiments and Transmission Electronic Microscopy experiments have been performed on several complexes formed by these core NHEJ proteins. We also characterized the interactions between these proteins by Size Exclusion Chromatography and Isothermal Calorimetry. These experiments have led to biochemical results sufficient to establish a solid basis to initiate the structural and functional study of the Human NHEJ Pathway.
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Pictography embedded in traditional African decorated walls and floors as an early cultural language : the case of three languages in Limpopo provinceNhlangwini, Andrew Dandheni 07 1900 (has links)
The colonial era brought about Western civilisation, industrialisation, urbanisation and technology that led to the negation of the validity of the traditional wall decorations and the meaning behind what is understood as merely decorative shapes and parttens. To research as to whether this is true, the aim of this study is to establish whether the symbols applied on the traditional African murals have any linguistic significance. The research investigated the pictography embedded in the traditional murals of three linguistic groups, namely the Balobedu, Vatsonga and Vhavenda in Limpopo Province.
The researcher gathered and recorded from the surviving elders the vital codes which unlock the meaning of signs, symbols, colours and geometric shapes before the knowledge is lost forever when they die. Data was collected mainly from Vatsonga female elders in their homes by using unstructured interviews. Traditional huts are decorated with symbols, signs, shapes, lines, and colours on the maguva (walls around the courtyard), mavala ya nghotsa (design and patterns, mainly in repeated half circles (figures 26 to 35)), mabilomu/swiluva/ swiphaswana (calabash/gourd flowers), ku sindza hi makholo (patterned cow dung floor) and ku tsema (coloured bands around the hut), depicted in figures 12 to 15. According to the respondents, the maphapha (calabashes/gourds) is a symbol for the plant that feeds the people. The plant from which maphapha are made, has heart-shaped green leaves and yellow flowers that develop into a calabash/gourd, which are consumed as food (figures 10–11). In this sense, it represents a woman and her responsibilities as carer and life giver.
The results affirm that the pictography is not merely a reproduction of common decorative patterns, but is instead the source of an ancient visual expressive language carried down from generation to generation through oratory and visual narratives in the form of symbols, and signs. The study recommends the preservation of the linguistic significance of the traditional South African murals that have long been marginalised, possibly encouraging the younger generations to review their own history. / African Languages / D. Litt. et Phil.(African Languages)
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"四庫全書"文獻在澳門的流傳及收藏利用研究 / Research on the circulation, possession and utilization of documents of Siku Quanshu in Macau;"四庫全書文獻在澳門的流傳及收藏利用研究"林金霞 January 2010 (has links)
University of Macau / Faculty of Social Sciences and Humanities / Department of Chinese
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Contribution à la conception d'un récepteur mobile failble coût et faible consommation dans la bande Ku pour le standard DVB-S / Contribution to the design of a low power and low cost 12-GHz receiver for DVB-S applicationsFouque, Andrée 04 June 2012 (has links)
Cette thèse présente une étude de faisabilité d'un récepteur faible coût et faible consommation pour l'extension du standard DVS-S à la mobilité. L'objectif de ce projet est de proposer de solutions pour lever les verrous technologiques quant à la réalisation d'un tel système en technologie CMOS 65 nm. Ce manuscrit de thèse articulé autour de quatre chapitres décrit toutes les étapes depuis la définition des spécifications du réseau d'antennes et de la chaîne de réception jusqu'à la présentation de leurs performances, en passant par l'étude de leurs architectures et de la conception des différents blocs. Suite à l'étude au niveau système et au bilan de liaison, le démonstrateur envisagé est constitué d'un réseau d'antennes (huit sous-réseaux de huit antennes microruban) suivi de la mise en parallèle de huit chemins unitaires pour satisfaire les exigences (Gain, facteur de bruit, rapport signal-à-bruit...) de l'application visée. Ce travail a abouti à la démonstration de la faisabilité d'une architecture innovante. Par ailleurs, nous avons aussi démontré sa non-application pour le standard DVB-S en raison des limitations en bruit de la technologie CMOS. Cependant des pistes existent pour améliorer le rapport signal-à-bruit du démonstrateur, à savoir l'utilisation d'un LNA (Low Noise Amplifier) avec une technologie compétitive en bruit et/ou d'un traitement du signal après la démodulation en bande par un processeur analogique. / This work focuses on the faisability of a low cost and low power receiver in order to extend the DVB-S standard to mobility. The objective of this project is to suggest solutions to overcome technological bottlenecks fot the realization of such a demonstrator with 65 nm CMOS technology. This report composed of four chapters, describes all steps from the specification definition to the performances of the antenna array and the receiver through the architecture study and the different blocks design. [...]
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“Worthy To Cherish and Perpetuate Our American Heritage:” Gender, Sexuality, and Adolescence in the 1920s Ku Klux KlanZmuda, Hannah Elizabeth 25 April 2022 (has links)
No description available.
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Billy Sunday and the Masculinization of American Protestantism: 1896-1935Hayat, A. Cyrus January 2008 (has links)
Indiana University-Purdue University Indianapolis (IUPUI)
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Saving Society Through Politics: the Ku Klux Klan in Dallas, Texas in the 1920sMorris, Mark N. (Mark Noland) 12 1900 (has links)
This study analyzes the rise of the 1920s Ku Klux Klan in Dallas, Texas, in the context of the national Klan. It looks at the circumstances and people behind the revival of the Klan in 1915. It chronicles the aggressive marketing program that brought the Klan to Dallas and shows how the Dallas Klavern then changed the course of the national Klan with its emphasis on politics. Specifically, this was done through the person of Hiram Wesley Evans, Dallas dentist and aspiring intellectual, who engineered a coup and took over the national Klan operations in 1922. Evans, as did Dallas's local Klavern number 66, emphasized a strong anti-immigrant, anti-Catholic ideology to recruit, motivate, and justify the existence of the Ku Klux Klan.
The study finds that, on the local scene, the Dallas Klavern's leadership was composed of middle and upper-middle class businessmen. Under their leadership, the Klan engaged in a variety of fraternal and vigilante activities. Most remarkable, however, were its successful political efforts. Between 1922 and 1924, the Klan overthrew the old political hierarchy and controlled city and county politics to such a
degree that only the Dallas school board escaped the Invisible Empire's domination. Klavern 66 also wielded significant control of state Klan operations and worked vigorously and with some success to elect Klan officials at the state level. As the dissertation shows, all of this occurred in the face of heavy and organized opposition from political elites and those who opposed the Klan on principle.
Finally, the dissertation looks at the complex combination of factors that brought the Klan's influence to an end. National scandals, internal squabbles, political failures, and longsuffering opposition from the mainstream press chipped away at the public's favorable impression of the Klan. Successful immigration restriction, an improving economy, and a lessening of post-war social tensions reduced the Klan's attractiveness. As a result, national and local Dallas membership dropped precipitously after 1924, and the Klan's dominance in local politics faded as well.
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