A diversificada e importante aplicação do lenho das plantações de eucalipto de rápido crescimento, com a aplicação de fertilização mineral, exigem a análise do seu efeito na qualidade do lenho. Com esse objetivo avaliou-se a dinâmica do incremento em diâmetro do tronco, as características anatômicas, físico-mecânicas e a concentração de nutrientes do lenho de árvores de Eucalyptus grandis, plantadas no espaçamento de 3x2 m e fertilizadas com potássio e sódio (no plantio, 6º, 12° mês). Foram selecionadas 60 árvores de eucalipto, no 22º mês, em 5 classes de área basal e avaliado o incremento em diâmetro do tronco, a cada 14 dias, de fevereiro de 2006 a fevereiro de 2010, através de dendrômetros. Para a amostragem do lenho em diferentes porcentagens da altura total do tronco foram selecionadas e cortadas árvores de eucalipto com a idade de 12, 24, 36 e 48 meses, em 5 classes de área basal. As amostras do lenho das árvores de eucalipto com 12, 24 e 36 meses foram utilizadas na avaliação das suas características anatômicas e determinação da densidade básica ponderada. Para as amostras do lenho das árvores de eucalipto com 48 meses foram analisadas as características anatômicas (fibras e vasos), físicas (densidade aparente e básica), mecânicas (resistência e rigidez à flexão estática e resistência a compressão paralela as fibras) nos tratamentos de fertilização, nas classes de área basal, nas posições radial e longitudinal do tronco e realizadas regressões múltiplas. Os resultados mostraram que as árvores de eucalipto dos tratamentos potássio e sódio e as de maior classe de área basal, apresentaram taxas de incremento do tronco superiores em relação às do tratamento controle e demais classes de área basal. Para o diâmetro do tronco das árvores foi detectado um efeito da sazonalidade climática, com períodos de máximo e mínimo crescimento. Houve diferença significativa entre os tratamentos de fertilização e classes de área basal das árvores para algumas características anatômicas e propriedades mecânicas; não foi observada diferença significativa para a densidade aparente e básica do lenho. Os maiores teores de potássio e de sódio foram encontrados no lenho das árvores dos respectivos tratamentos. A análise do teor de potássio e de sódio no lenho das árvores de eucalipto no 12º, 24º, 36º e 48º mês mostrou a maior retranslocação dos nutrientes nos respectivos tratamentos. Os resultados permitem concluir que os nutrientes, principalmente o potássio, induziu maior incremento em diâmetro e volume de lenho do tronco das árvores de eucalipto, sem alteração da sua densidade aparente e básica. A fertilização mineral influenciou algumas características anatômicas e propriedades mecânicas do lenho das árvores de eucalipto. O teor de potássio e de sódio variou nos tratamentos de fertilização, evidenciando a ocorrência de sua translocação no lenho das árvores ao longo da sua idade. / The diverse and important application of the wood in eucalyptus plantations of fast growth with the addition of mineral fertilizers, require the analysis of its effect on the woods quality. With this objective were evaluated the dynamics of the increment in trunk diameter, anatomical characteristics, physical-mechanical and nutrient concentration in Eucalyptus grandis trees planted at a spacing of 3x2 m and fertilized with potassium and sodium (at planting, 6, 12th month). Were selected 60 eucalyptus trees with 22 months, in five class of basal area and evaluated the increment in trunk diameter, every 14 days, from February 2006 to February 2010 through dendrometers bands. To sample the wood at different percentages of the total height of the trunk were selected and cut eucalyptus trees at the age of 12, 24, 36 and 48 months, in five class of basal area. The wood samples of eucalyptus trees with 12, 24 and 36 months were used in the evaluation of its anatomical and determination of the basic density. For eucalyptus trees wood samples with 48 months were analyzed the anatomic characteristics (fibers and vessels), physical (wood density), mechanical (strength and stiffness) in the treatment of fertilization, class of basal area, radial and longitudinal positions and multiple regressions. The results showed that the eucalyptus trees with the sodium and potassium treatments and the class of basal area upper had rates of growth upper than the control treatment and other class of basal area. For the trunk diameter of trees was detected a seasonal effect of climate, with periods of maximum and minimum growth. There were significant differences between fertilization treatments and class of basal area of trees to some anatomical characteristics, and mechanical properties; no difference was found for wood density. The higher concentration of potassium and sodium were found in trees of the respective treatments. The analysis of the content of potassium and sodium in the wood of the eucalyptus trees on the 12th, 24th, 36th and 48th months showed greater translocation of nutrients in the treatments. The results indicate that nutrients, particularly potassium, induced greater increase in volume and diameter of the eucalyptus trees trunk, without altering wood density. The mineral fertilization influenced some anatomical characteristics and mechanical properties of wood. The content of potassium and sodium varied in fertility treatments, indicating the occurrence of translocation in the wood of trees along its age.

Il existe actuellement une demande croissante pour le développement de méthodes expérimentales rapides et fiables permettant d'estimer la résistance à la fatigue dans le domaine de la fatigue à grands nombres de cycles. En ce sens, la fatigue ultrasonique apparue dans les années cinquante est très intéressante pour les industriels. En effet, la fréquence typique de ces essais est de 20 kHz ce qui permet d'atteindre le domaine des très grandes durées de vie en des temps d'essais raisonnables (109 cycles sont atteints en 14 h). Cependant ces essais posent le problème de l'effet de la fréquence et plus généralement de la validité des résultats obtenus pour estimer la durée de vie de structures chargées à des fréquences très inférieures à 20 kHz. L'objectif de ce travail est d'évaluer l'effet de la fréquence du chargement sur les mécanismes précurseurs de l'initiation de fissures et plus précisément sur les mécanismes de microplasticité à l'échelle du grain. Ce travail de thèse s’intéresse au cas du cuivre pur polycristallin sollicité en traction-compression alternée et symétrique. Pour mettre en évidence un effet de la fréquence, les courbes de Wöhler ont été construites à différentes fréquences. L’étude s’est ensuite focalisée sur les mécanismes de microplasticité précurseurs de l’initiation de fissures et plusieurs critères ont été examinés : les morphologies des bandes de glissement et leurs positions en lien avec la microstructure, les seuils d’apparition des bandes de glissement, le développement de ces bandes avec le nombre de cycles, la répartition de la microplasticité dans les grains, les valeurs d’énergie dissipée au cours d’un cycle. Le glissement dévié et la production-diffusion de lacunes sont deux mécanismes qui interviennent dans la formation des bandes de glissement et des extrusions en surface. Leurs rôles respectifs sur les effets de fréquence observés sont discutés. / Nowadays there is a growing demand for the development of fast and robust fatigue life prediction methods in the very high cycle fatigue domain. In this way, ultrasonic fatigue technique which appeared in 1950 is very interesting for manufacturers. Because the typical frequency of these tests is 20 kHz, this technique is efficient to perform tests up to a very high number of cycles in a reasonable time (109 cycles are reached in 14 h). However, the frequency domain of these fatigue tests facilities raises the issue of the effect of frequency and more generally the validity of the obtained results for estimating fatigue life of structures loaded at frequencies three or four order of magnitude below ultrasonic frequencies. The objective of this work is to evaluate the effect of the loading frequency on the precursors of fatigue damage, namely the microplasticity at the grain scale. This thesis work deals with the case of polycrystalline pure copper loaded in fully reversed tensioncompression. To show the effect of frequency, the Wöhler or S-N curves were constructed at different frequencies. Then, the study focused on the mechanisms of microplasticity preceding crack initiation and several criteria were investigated: the morphologies of the slip bands and their locations in the microstructure, the thresholds of appearance of the slip bands, the evolution of the slip bands amount with the number of cycles, the distribution of the microplasticity in the grains, the dissipated energy during a fatigue cycle. Cross slip and vacancies production and diffusion are two mechanisms which play a part in the formation of slip bands and extrusions in surface. Their respective roles on the effects of frequency observed are discussed

Il est bien établi que les propriétés mécaniques et rhéologiques d'une large classe de matériaux vitreux amorphes met en jeu – contrairement aux dislocations dans les cristaux – des rearrangements structuraux localisés formant par un processus de cascade des bandes de cisaillements. Cette localisation de la déformation est observée dans divers systèmes vitreux ainsi que dans des simulations numériques. Cette réponse mécanique complexe reste mal comprise à une échelle microscopique et il n'est pas clair si l'écoulement plastique peut être associé à une origine structurale locale ou à des processus purement dynamiques.Dans cette thèse nous envisageons ces problématiques à l'aide de simulations atomiques athermales sur un système Lennard-Jones modèle. Nous calculons le tenseur élastique moyenné localement sur une échelle nanométrique. A cette échelle, le verre est assimilable à un matériau composite comprenant un échafaudage rigide et des zones fragiles. L'étude détaillée de la déformation plastique à différents taux de cisaillement met en évidence divers régimes d'écoulement. En dessous d'un taux de cisaillement critique dépendant de la taille du système, la réponse mécanique atteind une limite quasistatique (effets de taille fini, cascades d'événements plastiques, contrainte seuil) alors que pour des taux de cisaillement plus importants les propriétés rhéologiques sont fixées par le taux de cisaillement imposé. Dans ce régime nous mettons en évidence la croissance d'une longueur de coopérativité dynamique et discutons de sa dépendance avec le taux de cisaillements. / It is commonly acknowledged that the mechanical properties and the rheology of a wide class of amorphous glassy materials involves – in contrast to dislocations in crystals – localized structural rearrangements that can form through a cascade mechanism shear bands. The phenomenon of strain localization has been observed experimentally in alloys, metallic and covalent glasses, polymers, complex fluids, granular media, foams, as well as in numerous simulations. This complex mechanical response remains poorly understood at a microscopical level and the origin of the plastic flow in driven glasses cannot be unambiguously attributed to either a local origin or to purely dynamic processes independently of any structural origin. In this thesis we approach these problems by the use of athermal atomistic simulations on a model Lennard-Jones glass. We compute the locally averaged elasticity tensor of the glass at a nanometric level. At this scale, the glass appears as a composite material composed of a rigid scaffolding and of soft zones. Moreover we use this local elastic order parameter to relate structure and dynamics in the sheared glass. The detailed analysis of the plastic deformation at different shear-rates shows that the glass follows different flow regimes. Below a system size dependent critical shear-rate the mechanical response reaches a quasistatic limit (finite size effects, cascades of plastic rearrangements, yield stress) while at higher shear rates the rheological properties are determined by the externally applied shear-rate. In the later regime we report on the growth of a cooperativity length scale and discuss the scaling of this length with shear-rate.

Philosophiae Doctor - PhD / In the first experiment high spin states in 194Tl, excited through the 181Ta (18O, 5n) heavyion fusion evaporation reaction were studied using the AFRODITE array at iThemba LABS. The γ-γ coincidences, RAD ratios and linear polarization measurements were carried out and the previously known level scheme of 194Tl was significantly extended. A total of five rotational bands four of which are new were observed. A pair of rotational bands associated with the πh9/2 ⊗ νi−1 13/2 configuration at lower spins and with the πh9/2 ⊗ νi−3 13/2 configuration at higher spins was found and interpreted as the first possible chiral bands followed above the band crossing. The two 4-quasiparticle bands show exceptionally close near-degeneracy in the excitation energies. Furthermore close similarity is also found in their alignments and B(M1)/B(E2) reduced transition probability ratios. In the second experiment lifetimes in 194Tl were measured using the DSAM technique with the excited states in this nucleus populated through the 181Ta (18O, 5n) reaction. A total of 25 lifetimes and 30 reduced transition probabilities of magnetic dipole B(M1) and electric quadrupole B(E2) have been evaluated. Furthermore B(M1) and B(E2) reduced transition probabilities in Bands 1 and 4, which have been regarded as chiral candidates, were found to be close to each other and reveals strong splitting along spin values. This further supports the proposed chiral nature of these two bands.

La télémédecine et plus particulièrement la télémédecine mobile semble représenter l’avenir en termes de soins médicaux. Ce concept nécessite cependant pour sa viabilité, de disposer d’éléments rayonnants miniatures, fortement efficaces, et capables de communiquer sur plusieurs bandes. Ce mémoire présente la méthodologie de conception et l’optimisation d’antennes miniatures intégrées, dédiées à un dispositif spécifique permettant de réaliser une liaison radiofréquence entre un implant médical et le téléphone portable d’un patient. Cependant, la miniaturisation des antennes, éléments clés de ce concept, s’accompagne généralement d’une dégradation de son efficacité et de sa bande passante, ce qui rend délicat leur mise en œuvre sur au moins deux des points essentiels recherchés. La conception de ce type d'antennes nécessite donc une analyse très fine des phénomènes physiques mis en jeu dont notamment la limite théorique en termes de performances que l'on peut atteindre pour une antenne circonscrite à un volume donné. De plus, ces performances radioélectriques sont fortement dépendantes de l'environnement dans lequel est placée l’antenne. Par conséquent, l'influence de chaque partie constituant cet environnement doit être prise en compte lors de l'intégration, ce que nous décrivons également dans ce manuscrit à travers différentes solutions d’éléments rayonnants. / This thesis presents the design and the optimization of miniature antennas integrated in specific devices dedicated to ensure communications between medical implants and a mobile phone in the context of telemedicine applications. However, the miniaturization of antennas necessarily implies a degradation of efficiency and bandwidth, which makes it difficult for implementation. Then, the design of electrically small antennas requires a very good understanding of the physical phenomena such as the theoretical limits of performance in terms of bandwidth and efficiency that can be expected for a radiating element with given dimensions. Furthermore, the performance of an electrically small antenna is also highly dependent on the environment in which it is mounted. Therefore, its interaction with each part of its close environment was highlighted and analyzed.

Les milieux granulaires sont très étudiés depuis des décennies mais la description de l'ensemble des comportements observés de ces matériaux reste une grande question ouverte. Lorsqu'ils sont soumis à une contrainte suffisamment importante, une caractéristique est de présenter de la localisation de la déformation. L'objectif du travail présenté dans ce mémoire est d'étudier expérimentalement et numériquement la déformation d'un milieu granulaire et de caractériser des comportements observés lors d'un text biaxial. La première partie est consacrée à la réalisation des tests biaxiaux en déformation plane. Pour pouvoir visualiser de très petites déformations, nous utilisons une méthode interférométrique basée sur la diffusion multiple de la lumière. La deuxième partie est dédiée à la modélisation numérique d'un test biaxial en 2D dans des conditions similaires à celles de l'expérience par la méthode des éléments discrets. Enfin, dans la dernière partie, des outils développés pour l'analyse d'images utilisés pour étudier aussi bien les expériences que les simulations numériques sont abordés. L'étude du champ plastique moyen dans les expériences montre que la localisation de la déformation est un processus progressif initié par une bifurcation qui correspond à l'apparition d'une direction bien définie. Cette direction est en accord avec l'angle de Mohr-Coulomb et son apparition a lieu avant la rupture du matériau. L'étude des fluctuations de la plasticité dans les expériences et les simulations numériques semble mettre en évidence une croissance d'une longueur caractéristique. / Granular materials have been studied for decades, but the description of the behaviors observed of these materials is still an open question. They display localization of deformation when submitted to a large enough stress. The objective of this work is to study experimentally and numerically the deformation of a granular material and to characterize observed behaviors in a biaxial text. The first part is devoted to the realization of plane strain biaxial tests. In order to visualize very small deformations, we use an interferometric method based on the multiple light scattering. The second part is devoted to the numerical modeling of a 2D biaxial test under conditions similar to those of the experiment by the discrete element method. Finally, in the last part, tools developed for the analysis of images used to study as well the experiences as the numerical simulations are approached. The study of the average plastic field in the experiments shows that the localization of the deformation is a progressive process initiated by a bifurcation which corresponds to the appearance of a well defined direction. This direction is in agreement with the angle of Mohr-Coulomb and its appearance takes place before the failure of the material. The study of the fluctuations of the plasticity in the experiments and the numerical simulations seems to show an increase of a characteristic length.

Paul Robert Fauchet's Symphonie pour Musique d'Harmonie, known in the United States as Symphony in B-flat, is a four-movement composition spanning nearly thirty minutes in length and written in the style of the late romantic composers. Despite its place as one of the first symphonies for wind band, a performance of the piece that represents the composer's 1926 orchestration is difficult due to the inclusion of instruments that are no longer in common practice, including bugles, alto horns, and saxhorns. Later American editions of the work by James Robert Gillette (1933) and Frank Campbell-Watson (1948/1949) replaced these instruments, but also took several other liberties with orchestration and voicing. The primary purpose of this study was the creation of a performance edition of the Symphony for modern wind band that is accessible to a larger audience of performers and listeners. The method involved in creating the modern edition eliminates errors of extant editions and clarifies a number of the discrepancies surrounding the symphony's multiple publications. This edition attempts to retain the composer's voicing and orchestration choices. To accomplish this, the present project considered where modern instrumentation differed from the original sources and attempted to balance timbral similarities between those instruments, while also considering ease of comprehension for a modern ensemble to perform the work. Sources used to create this edition included all published editions of scores and parts, as well as a newly created full score of the 1926 printed parts. The study concludes with the inclusion of the full score of the new performance edition.

The United States Military Academy Band, also known as the West Point Band is the oldest active band in the United States Army and the oldest unit at the United States Military Academy, and is considered to be one of the finest military musical organizations in the world. The band has also been instrumental in facilitating the creation of new works for wind band.As the commissioning of new music has been essential to the expansion of the wind band's repertoire, several major commissioning projects were undertaken in the mid-twentieth century by various organizations, including the West Point Band, the Goldman Band in conjunction with the League of Composers and later the American Bandmasters Association, Kappa Kappa Psi and Tau Beta Sigma, the American Wind Symphony, and the College Band Directors National Association. These commissioning projects and many others have contributed hosts of new quality works to the repertoire of the wind band. The West Point Band's 1952 commissioning project celebrating the Sesquicentennial of the United States Military Academy was among the first of these mid-twentieth century commissioning projects to seek out prominent composers of the day and have them write works for wind band. The project contributed several seminal pieces to the wind band's repertoire, including Morton Gould's Symphony for Band: West Point. In 1996, as tribute to both the Academy and to the earlier commissioning project, the West Point Band sought to celebrate the Academy's 2002 bicentennial in a similar fashion by commissioning well-known composers to contribute substantial wind works. These pieces would be premiered and recorded by the West Point Band over a number of years, including a gala Bicentennial Celebration concert at Carnegie Hall in March 2002. The purpose of this study is to create a consolidated written record of the wind music composed for the West Point Band as part of the band's Bicentennial Wind Commissioning Project, and to describe the process and circumstances by which this music was created and premiered. The continuing development of a quality original repertoire is important to the wind band community as a whole, and commissioning composers to write wind band music is the primary means by which new music is acquired. By any account, the twenty-six works produced through the West Point Band's Bicentennial Commissioning Project constitute a significant contribution to this repertoire. As this project and many of these pieces are not well known, it is the author's intent to bring increased attention to this commissioning project and to this music.

The synthesis of in-situ bulk metallic glass composites (BMGCs) with crystals that undergo a martensitic transformation under loading is possibly the most effective method to improve the plasticity of metallic glasses at room temperature. These martensitic or shape memory BMGCs are typically fabricated via solidification of glass-forming melts, which requires the meticulous selection of the chemical composition and the proper choice of the processing parameters (particularly the cooling rate) in order to ensure that the glassy matrix coexists with the desired amount of austenitic phase having suitable morphology and characteristics. Unfortunately, a relatively limited number of alloy systems, where austenite and glassy matrix coexist over a wide range of compositions, is available. Additionally, the necessity for rapid heat extraction and the corresponding high cooling rates essential for glass formation by melt solidification set an inherent limit to the achievable dimensions of BMGs and BMGCs specimens. The aim of this thesis is to study the effectiveness of powder metallurgy as an alternative to solidification for the synthesis of shape memory BMGCs. Ni50.6Ti49.4 and Zr48Cu36Al8Ag8 metallic glass powders were selected as the constituents of the composites because they have been extensively investigated and represent well the characteristic behavior of metallic glass and shape memory phases. BMGCs with different volume fractions of NiTi phase were fabricated using pressure-assisted sintering via hot pressing and their microstructure, mechanical properties and deformation mechanism were investigated. Particular focus was placed upon identifying the individual contributions of the martensitic transformation and shear band formation to plasticity as well as their mutual interaction at different length scales using a multidisciplinary approach involving experiments and simulations. BMG composites were synthesized by hot pressing of powder mixtures consisting of Zr48Cu36Al8Ag8 metallic glass and different amounts of Ni50.6Ti49.4 particles (10, 20, 40 and 60 vol.%) using the optimized consolidation parameters (temperature-time-pressure) determined for the monolithic BMG. All composites are characterized by a relatively uniform particle distribution and good interface bonding without any sign of reaction between the metallic glass and NiTi. The NiTi particles are progressively less isolated with increasing volume fraction of NiTi up to 40 % and, for the BMGC with 60 vol.% NiTi, the glassy particles are no longer connected and the NiTi phase becomes the continuous matrix. This is not a trivial achievement as the change of matrix while maintaining the structure of the constituent phases would not be easily obtained by solidification of melts with such different compositions. The size of the samples (10 mm diameter and 9 - 11 mm height) is larger than the characteristic BMGCs synthesized by casting and can, in principle, be scaled up to larger dimensions, demonstrating the effectiveness of this approach for overcoming the size limitation inherent to glass formation via solidification. In contrast to the monolithic BMG, which does not show any sign of plasticity, the BMGCs exhibit macroscopic plastic deformation that progressively increases with increasing NiTi content along with distinct strain-hardening. The BMG composites have similar fracture strength, which is comparable with the monolithic BMG, and exhibit a distinct double yield behavior, similar to shape memory BMGCs fabricated by casting. The deformed BMGCs exhibit a high density of shear bands, again in agreement with what observed for similar BMGCs fabricated by casting. These findings not only demonstrate that BMGCs with tunable microstructures and thus with optimized deformability can be synthesized by pressure-assisted sintering but, thanks to the phase stability of the components across such a wide range of compositions, also offer an excellent platform to examine fundamental aspects in the field of martensitic BMGCs. The confining stress exerted by the surrounding glassy matrix was quantified at the macroscale via a hybrid Voigt-Reuss mixture, which considers intermediate weighted combinations of stiff and compliant behaviors. In this way, the macroscopic stress required to initiate the martensitic transformation from B2 to B19´ can be described with rather good accuracy. The confining effect was further investigated by in-situ high-energy X-ray diffraction to have access to the strain tensor of the B2 phase as a function of loading. The results indicate that the confining stress along the direction perpendicular to the loading axis is particularly strong because the expansion of the B2 phase is constrained by the elastic matrix. A mechanism responsible for shear band formation in shape memory BMGCs is proposed. The stress field generated by the martensitic transformation in the contiguous glass would activate the adjacent shear transformation zone (STZ, the elementary units of plasticity in BMGs). The stress field induced by the activated STZ in the surrounding material then triggers the activation of the following STZs along the path of a potential shear band, in an autocatalytic process resembling the domino effect. The shear band formed in this way propagates through the glassy phase and, when impinging a B2 particle, the associated stress field would locally trigger the martensitic transformation, starting again the process. Molecular dynamics (MD) simulations of a martensitic BMGC show that the structural perturbation generated by the martensitic transformation is indeed transmitted to the adjacent glassy matrix and, in turn, to the developing shear band, in agreement with the proposed mechanism. The individual contribution of the glassy phase to the residual strain after each loading-unloading cycle was quantified assuming that the NiTi phase behaves in the same manner across the different specimens. The glass contribution was then correlated to the shear band density to obtain the plastic strain resulting from shear banding for a given amount of NiTi phase, a quantity that could be effectively used in the design of plastically-deformable BMGCs with shape memory particles. The martensitic transformation in the composites becomes progressively more irreversible with increasing strain. A large contribution to the martensite stabilization may come from the residual stress induced by the shear bands, in accordance with the finite element method (FEM) simulations, showing that residual stresses in the composites suppress the reverse transformation after unloading. These finding corroborates the hypothesis that the residual elastic stress field generated by the shear bands may be fundamental for stabilizing the martensitic phase by restraining the atoms at the glass-crystal interface from rearranging back to form austenite. This process can be reversed by proper heat treatment. The findings presented in this thesis offer the opportunity to synthesize shape memory BMG composites with enhanced plasticity and strain-hardening capability along with larger dimensions than those typically achieved by solidification. The powder metallurgy approach provides the necessary versatility in materials design and resulting properties of the composites via the control over the fundamental microstructural features, such as volume fraction, size, morphology and distribution of the second phase. Additionally, materials processing in the solid state gives a virtually infinite choice among the possible composite components, a degree of freedom not usually given when processing via solidification.:Abstract iii Kurzfassung vii Motivation and objectives xi 1 Theoretical background and state-of-the-art 1 1.1 Bulk metallic glasses (BMGs) 1 1.1.1 Formation of metallic glasses 2 1.1.2 Mechanical properties of BMGs 5 1.1.3 Shear bands in metallic glasses 8 1.2 Bulk metallic glass matrix composites 19 1.2.1 Fabrication of BMG composites 20 1.2.2 In-situ BMG composites 27 1.2.3 Ex-situ BMG composites 43 2 Experiments and simulations 57 2.1 Sample preparation 57 2.1.1 Starting materials 57 2.1.2 Powder mixing 59 2.1.3 Powder consolidation 60 2.2 Materials characterization 61 2.2.1 Composition analysis 61 2.2.2 Laboratory X-ray diffraction 61 2.2.3 High-energy X-ray diffraction and strain analysis 62 2.2.4 Viscosity measurements 63 2.2.5 Differential scanning calorimetry 64 2.2.6 Density measurements 64 2.2.7 X-ray computed tomography 65 2.2.8 Optical microscopy and scanning electron microscopy 65 2.2.9 Transmission electron microscopy 66 2.2.10 Elastic constants measurements 66 2.2.11 Mechanical tests 67 2.3 Molecular dynamic simulations 67 2.4 Finite element simulations 68 3 Pressure-assisted sintering of single-phase Zr48Cu36Al8Ag8 metallic glass and Ni50.6Ti49.4 powders 73 3.1 Synthesis and properties of single-phase Zr48Cu36Al8Ag8 bulk metallic glass 73 3.2 Synthesis and properties of single-phase Ni50.6Ti49.4 shape memory alloy 80 4 Pressure-assisted sintering of BMG composites with shape memory crystals: Microstructure and mechanical properties 87 4.1 Microstructure of BMG composites 87 4.2 Effect of NiTi volume fraction on mechanical properties 90 4.3 Effect of confinement of the glassy phase on the martensitic transformation 95 5 Deformation mechanism of shape memory BMG composites 101 5.1 Martensitic transformation and shear band formation 101 5.2 Mechanism of shear band formation in shape memory BMG composites 107 6 Reversibility of the martensitic transformation in shape memory BMG composites 113 6.1 Martensite stabilization in NiTi alloy and BMG composites 113 6.2 Simulation of the martensite stabilization effect in BMG composites 119 6.3 Effect of heat treatment on the martensitic reverse transformation 121 7 Summary and outlook 125 References 131 Acknowledgements 155 Publications 157 Erklärung 159

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.