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Měření intenzity provozu během pevně daných intervalů v AP / Measurements of the intensity of traffic within a fixed interval of the APKubík, Pavel January 2011 (has links)
The thesis analyzes the network traffic on a router with open source firmware. First is chosen a software platform, based on compatibility with available equipment. Then are assessed properties necessary for the development of custom applications. Support for various programming languages provided by the SDK, development environment and the available modules and libraries, for working with network interface. Based on these factors is then chose method to realize the program. He is implemented on the OpenWRT firmware in C / C + + using network library pcap. These funds are used to capture and analyze network traffic. Obtained data are processed using methods of technical analysis, namely on the basis of moving averages, Stochastic oscillator and Bollinger bands. Based on results of these methods are generated and verified estimates of traffic. They are based on linear extrapolation, simplified for fixed intervals. The validity of each method is verified on base of the estimated value. Method is verified if estimated value of the traffic volume is in the Bollinger band, which is given by the standard deviation. Each method is tested several times in real traffic with different input parameters. Then is evaluated the influence of parameters on the error rate of methods. Individual methods are compared and evaluated based on the behavior in different scenarios and based on the average relative error.
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Výkonový zesilovač pro krátkovlnné pásmo s inteligentním snímáním výkonu / Power amplifier for shortwave bands with intelligent measurment of powerZatloukal, Petr January 2012 (has links)
The target of this master’s thesis is to design a functional sample of radiofrequency power amplifier for short waves radio amateur bands and measure its basic parameters such as required input power, output power, output spectrum purity and efficiency. The construction is based on results of behavioral simulation of the amplifier’s model obtained from circuit simulator cadence™OrCAD 16. The amplifier ought to be later used as an output stage for a small radio amateur transceiver.
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Evolution de la posture rachidienne au cours de la croissance normale et modifications dans la scoliose idiopathique de l'adolescent / Spinal posture evolution with normal growth and changes in adolescent idiopathic scoliosisPesenti, Sébastien 14 December 2018 (has links)
L’évaluation classique de la posture rachidienne chez les patients porteurs d’une scoliose idiopathique de l’adolescent (SIA) se fait habituellement dans une position contrainte et statique en radiographie standard. Les conséquences sur la fonction rachidienne dynamique de ces déformations sont mal connues. Par ailleurs, les changements de la posture rachidienne au cours de la croissance et avec l’acquisition d’une marche stable n’ont encore jamais été explorés. L’analyse quantifiée du mouvement (AQM) d’une cohorte d’enfants sains a permis de mettre en évidence des modifications de la posture rachidienne dynamique au cours de la croissance, avec une augmentation de la gîte du tronc vers l’avant. Ces modifications s’accompagnaient de modifications anatomiques, en particulier au niveau des facettes articulaires cervicales. En AQM, les patients porteurs d’une SIA avaient des modifications du schéma de marche avec un décalage de phase à la marche entre la rotation des épaules et du bassin chez les patients scoliotiques. Il n’y avait pas de différence dans le schéma de marche entre les patients ayant une courbure thoracique droite et ceux ayant une courbure lombaire gauche. L’analyse de ces patients à 11 mois postopératoire a montré une restauration de certains paramètres grâce à la fusion vertébrale. Notamment, l’arthrodèse rachidienne postérieure de la courbure scoliotique a pour effet de faire disparaître le décalage de phase dans le plan transversal. L’AQM permet de mettre en évidence des modifications de la posture rachidienne chez ces patients et apparait comme un outil d’évaluation fondamental, qui pourrait nous permettre de mieux évaluer les traitements de la SIA. / In adolescent idiopathic scoliosis (AIS) patients, spinal posture is usually assessed in a constraint position with radiographic evaluation. However, the consequences of spinal deformity in these patients on the daily functioning of the spine remains unclear. On the other hand, spinal posture changes with normal growth and mature gait achievement have never been explored.A gait analysis was performed on a cohort of healthy children and highlighted changes in dynamic spinal posture with growth, showing that the trunk was increasingly leaning forward with mature gait achievement. These modifications were associated with anatomical changes, especially in the cervical spine.Changes in gait pattern were also observed in AIS patients thanks to gait analysis. In particular, there was a modification of upper trunk and pelvic rotation during gait. There was no difference in gait pattern according to major curve location. Eleven month postoperatively, our results showed that spinal fusion allowed restoration of a normal gait pattern, especially in the transversal plane.Gait analysis was able to highlight changes in dynamic spinal posture that occur in AIS patients, and thus appears as a major tool for spinal posture assessment in these patients. It could help us to improve the evaluation of the treatments that are proposed for spinal deformity correction.
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Évaluation des technologies d'impression 3D pour le développement d'antennes directives à large bande passante pour les liaisons backhaul en bandes millimétriques V et E / Evaluation of 3D printing technologies for the development of wide-band directive antennas for millimeter wave backhaul links in E and V frequency bandsNachabe, Nour 06 December 2018 (has links)
Face à la demande croissante de débits de données de plus en plus élevées, l’une des principales solutions proposées par la 5G est de densifier le réseau en y intégrant notamment de nouvelles « Small cells ». La réorganisation de l’architecture du réseau mobile pour s’adapter à l’intégration poussée de ces Small cells, fait naître la problématique de la connexion backhaul entre les stations de bases desservant les Small cells et le cœur de réseau. Ainsi, des liaisons backhaul de plusieurs Gb/s de données sont nécessaires pour pouvoir assurer un débit de données d’au moins 100Mb/s à l’utilisateur qui est l’un des objectifs fixés pour la 5G. Les solutions de connexion backhaul sans fils ont un avantage indiscutable face aux coûts de déploiements de fibres optiques qui sont très élevés. Pour augmenter la capacité spectrale des liaisons sans fils, l’utilisation des fréquences millimétriques au-delà de 6 GHz caractérisées par des larges bandes passantes sera prochainement discutée pour la 5G durant le World Radiocommunication Conference 2019. Parmi ces fréquences, les bandes V (57-66GHz) et E (71-76 GHz et 81-86 GHz) ont un intérêt indéniable grâce aux larges bandes passantes disponibles ainsi qu’aux conditions de licenciement peu exigeantes. Les travaux développés dans cette thèse consistent à concevoir des antennes directives à large bande passante permettant d’établir les liens backhaul point-à-point sans fils (LoS). En exploitant les technologies de fabrications à faibles coût telles que l’impression 3D et Printed Circuit Board (PCB) sur des substrats FR4, la conception de deux types d’antenne directives a été étudiée à savoir des antennes lentilles et des antennes réseaux. / In order to address the ever-increasing demand of higher data rates, adding small cells to the existing macrocells infrastructure is one of the most important milestones of the 5G roadmap. With the integration of small cells and the re-organization of the network topology, backhaul bottleneck is the main challenge to address in the near future. Facing the costs of deployments of fiber optic connections, point-to-point wireless backhaul links using millimeter wave (mmW) frequencies are gaining prominence. 5G future frequencies, to be discussed under the World Radiocommunication Conference 2019 (WRC-19) open-up the way towards mmW frequency band where large bandwidths are naturally available. The high bandwidths available at these frequencies enable several Gbps data rate backhaul links, which is un utmost necessity to respect the 100 Mbps user-experienced data rate promised by the 5G standard. Millimeter-wave frequencies in V and E-bands unlicensed/light licensed spectrum are considered as primary candidates for backhaul links. In addition to the light license regime, the high free space path loss experienced at these frequencies is rather beneficial to limit the interference between small cells links. Moreover, the high available bandwidths at V and E-bands enable to achieve multi Gb/s links without using complex modulation schemes. In this thesis, we focused our research study on developing high gain wide-band antennas usable in point-to-point backhaul links in a Line of Sight (LoS) context. Leveraging cost-efficient technologies like 3D printing and Printed Circuit Board (PCB) on FR4 substrates, we studied two high-gain antenna types: lens antennas and flat array antennas.
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Iridium(III) phosphorescent complexes with dual stereogenic centers: single crystal, electronic circular dichroism evidence and circularly polarized luminescence propertiesLi, Tian-Yi, Zheng, You-Xuan, Zhou, Yong-Hui 19 December 2019 (has links)
Iridium complexes with a chiral metal center and chiral carbons, Λ/Δ-(dfppy)₂Ir(chty-R) and Λ/Δ-(dfppy)2Ir(chty-S), were synthesized and characterized. These isomers have the same steadystate photophysical properties, and obvious offsets in ECD spectra highlight both the chiral sources. Each enantiomeric couple shows mirror-image CPL bands with a dissymmetry factor in the order of 10ˉ³.
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The relationship between collegiate band members' preferences of teacher interpersonal behavior and perceived self-efficacy.Steele, Natalie Anne 05 1900 (has links)
The first purpose of this study was to describe collegiate band members' preferred teacher interpersonal behaviors and perceptions of self-efficacy based on the gender, year in college, instrument, and major. The second purpose of the study was to measure the relationship between preferences of interpersonal teacher behavior and self-efficacy scores. The non-probability purposive sample (N = 1020) was composed of band members representing 12 universities from different regions of the United States. There were 4 large public, 4 small public, and 4 private universities that participated in the study. Participants completed 2 questionnaires, the Teacher Interaction Preference Questionnaire (TIPQ) and the Self-Efficacy Questionnaire (SEQ). Descriptive statistics were calculated for each of the questionnaires. Results for the TIPQ showed that all sub-groups most preferred the dominant-cooperative behaviors, followed by submissive-cooperative behaviors, and least preferred the dominant-oppositional behaviors. Results for the SEQ showed subtle variations for all subgroups. Three Pearson product-moment correlation coefficients were calculated to measure the relationship between the three teacher interaction styles (dominant-cooperative, submissive-cooperative, dominant-oppositional) and students' perceived self-efficacy. Due to the possible over-use of the data with multiple correlations, a Bonferroni adjustment was made to avoid a Type I error (.05/3 = .016). A significant positive relationship was found between self-efficacy and dominant-cooperative with 22% shared variance. A significant positive relationship was found between self-efficacy and submissive-cooperative with 7% shared variance. Finally, a significant positive relationship was found between self-efficacy and dominant-oppositional with 5% shared variance. This study's results indicate that it may be beneficial for band directors to measure students' preferences and perceptions of teacher interpersonal teacher behavior in order to find ways to interact better with the students. In addition, due to the relationship between students' preferences of teacher interpersonal behavior and perceived self-efficacy, collegiate band directors may wish to examine their own behaviors to determine how they align with the students' preferences.
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"Něžné zbraně": Múzické instituce socialistické armády v Československu, NDR a Polsku / "Gentle Weapons": Socialist military's institutions for performing arts in Czechoslovakia, GDR and PolandŠmidrkal, Václav January 2014 (has links)
This doctoral dissertation compares three types of military institutions of performing arts-military bands, military theatres and military artistic ensembles in cases of Czechoslovakia, German Democratic Republic and Poland since World War II to the fall of communism. Powered by TCPDF (www.tcpdf.org)
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Automatický anténní tuner / Automatic Antenna TunerŠváb, Jaroslav Unknown Date (has links)
This degree work deals with the design and implementation of an automatic antenna tuner for short-wave transmitters. The device works within the short-wave range in (1.5 MHz - 30 MHz) band according to the selection of the given frequency. Its principle is that the tuner has a small range of adapted impedances, but it is usually sufficient for fine tuning of most deviations in the system of antenna 50 - feeder 50 - transceiver outlet 50 . It is also equipped with memories which the settings for the individual bands or frequency segments are stored into. Then the transition from one band to another is quick, easy and, first of all, safe, which is a great advantage. In automatic mode, a SWR limit from which the tuner should start to tune can be set. Interconnection with a TRX is not necessary in a fully automatic mode, the device tunes automatically after keying if the set limit of SWR has been exceeded. The automatic tuning is very quick with this device, if the antenna being tuned is not stored in the memory the tuning lasts ca 0.5 - 6 s, if the tuner uses the memory. It could be said that the work with the tuner is without problems, it is possible to learn to control it in a short time. The tuner is small and light. The result of the whole project is a compact device controlled by the user by means of push buttons.
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Investigations on the Formation of Defect Bands in Semi-Solid High Pressure Die Cast Aluminium-Silicon AlloysLaw, Madeleine January 2020 (has links)
High-pressure die casting of semi-solid aluminium-silicon alloys is used in the automotive industry to manufacture components, like housings, brackets, and bars. It is commonly known that during high-pressure die casting, defect bands may be created that follow the contour of the component surface. These bands consist mainly of a eutectic phase. This phenomenon is also observed in semi-solid metal slurry high-pressure die casting. These bands could lead to premature failure of the component in service. The origin of these bands is not fully understood and so this research focuses on investigating these bands and their origins further. A series of casting trials were conducted with varying plunger velocity. Subsequent investigation using optical and scanning electron microscopy showed that a change of the plunger velocity alters the number of bands present in the samples. Energy dispersive X-ray spectroscopy revealed that a measurable difference in aluminium quantity across the band was noticed and it was postulated that aluminium migrates towards the component centre. Therefore, different mechanisms responsible for particle migrations found in literature were investigated and assessed quantitatively using experimental data and information from published literature. It was found that the Saffman lift force and the Mukai-Lin-Laplace effect were the mechanisms that were most likely to cause such a migration of aluminium. Further experimental investigation is recommended to identify which of the two mechanisms is ultimately responsible for the migration and to optimise the high-pressure die casting procedure to minimise defect band formation. / Produktion av högtrycksgjutning av halvfasta aluminium-kisellegeringar används i fordonsindustrin för att tillverka komponenter, som exempel till kåpor, konsoler och stag. Det är allmänt känt att defektband kan formas under högtrycksgjutning som följer konturen av komponentytan. Dessa band består huvudsakligen av eutektisk fas. Detta fenomen har också observerats vid högtrycksgjutning produktion av halvfast slurry. Potentiellt kan dessa band leda till en försämring av komponentens mekaniska egenskaper och resultera i ett förtida brott. Ursprunget av dessa band är inte helt kartlagda och det är därför viktigt att fokusera ytterligare på denna forskning och att undersöka dessa band och deras ursprung. En serie med gjutningsförsök genomfördes med varierande kolvhastighet. Efterföljande undersökning med optisk- och svepelektronmikroskopi visade att en förändring av kolvhastigheten förändrar antalet band som finns i proverna. Energidispersiv röntgenspektroskopi avslöjade en mätbar skillnad i aluminiumkvantitet över bandet, och det antogs att aluminium migrerar mot centrum av komponenten. Därför undersöktes och utvärderades olika mekanismer som ansvarar för partikelmigrationer som finns att finna i litteratur med hjälp av experimentella data och information från publicerad litteratur. Det visade sig att Saffman lyftkraft och Mukai-Lin-Laplace effekten var de mekanismer som mest troligen orsakade migration av aluminium. Ytterligare experimentella försök rekommenderas för att identifiera vilken av dessa två mekanismerna som i slutändan är ansvarig för migrationen. Detta för att optimera gjutningsprocessen och därmed minimera uppkomsten av defektband.
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[en] ANALYTICAL MODELING OF DEFORMATION BANDS GENERATION IN SANDSTONE RESERVOIRS / [pt] MODELAGEM ANALÍTICA DA GERAÇÃO DE BANDAS DE DEFORMAÇÃO EM RESERVATÓRIOS ARENÍTICOSLEANDRO GUEDES CARVALHO 12 August 2021 (has links)
[pt] A predição da permeabilidade é uma etapa crítica no fluxo de caracterização e modelagem geológica de reservatórios e essencial para o desenvolvimento de projetos de produção. Estruturas subsísmicas denominadas bandas de deformação (BD) podem diminuir a permeabilidade em até seis ordens de grandeza em relação à rocha matriz de reservatórios areníticos e podem, dessa forma, atuar como barreiras totais ou parciais ao fluxo de fluidos.
O presente trabalho pretende contribuir na determinação do comportamento hidráulico de reservatórios propondo um modelo geomecânico analítico para a predição de BD em reservatórios de arenitos. Em termos práticos, o objetivo é prever se em uma determinada porção de um depósito siliciclástico de hidrocarboneto foram atingidas condições para a formação de BD, ou quão próximo se está de uma possível geração dessa feição a fim de se sugerir uma análise da redução de permeabilidade. A proposta se estende na implementação computacional do método e sua aplicação em um estudo de caso de um reservatório arenítico pouco consolidado da margem continental brasileira rico em BD.
Os resultados confirmaram a viabilidade do método mostrando que a porção do reservatório analisada atingiu as condições mecânicas para a gênese de BD a partir da idade geológica intitulada de Oligoceno (~ 23 a 35 Ma) para os cenários estabelecidos. / [en] The permeability prediction is a critical step in the flow of geological modeling and reservoir characterization and is essential for the development of production projects. Sub-seismic structures called deformation bands (BD) can reduce permeability up to six orders of magnitude in relation to the host reservoir sandstone and can thus act as total or partial barriers to the fluid flow.
The present work intends to contribute in the determination of the hydraulic behavior of reservoirs proposing an analytical geomechanical model for BD s prediction in sandstone reservoirs. In practical terms, the objective is to predict whether the conditions in a given portion of a siliciclastic hydrocarbon deposit have been reached for the localization of BD or how close it is to a possible generation of this feature in order to suggest an analysis of the permeability reduction. The proposal extends to the computational implementation of the method and its application in a case study of a poorly consolidated sandstone reservoir on the brazilian continental margin, rich in BD.
The results confirmed the viability of the method by showing that the portion of the analyzed reservoir reached the mechanical conditions for the genesis of BD from the geological age entitled Oligocene (~ 23 to 35 Ma) for the established scenarios.
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