Hyper-wideband communications represent the next frontier in spread spectrum RF systems with an excess of 10 GHz instantaneous bandwidth. In this thesis, an end-to-end physical layer link is implemented featuring 16k-OFDM with a 4 GHz-wide channel centered at 9 GHz. No a priori channel state information is assumed; channel information is derived from the preamble and comb pilot structure. Due to the unique expansive spectral properties, the channel estimator is primarily composed of least squares channel estimates combined with a robust support vector statistical learning approach using autonomously selected parameters. The system’s performance is demonstrated through indoor wireless experiments, including line-of-sight and near-line-of-sight links. Moreover, it is shown that the support vector approach performs superior to linear and cubic spline inter/extrapolation of the least squares channel estimates.

Background: Clopidogrel is commonly prescribed to cats with perceived increased risk of thromboembolic events, but little information exists regarding its antiplatelet effects. ObjectiveTo determine effects of clopidogrel on platelet responsiveness in cats with or without the A31P mutation in the MYBPC3 gene. A secondary aim was to characterize variability in feline platelet responses to clopidogrel. AnimalsFourteen healthy cats from a Maine Coon/outbred mixed Domestic cat colony: 8 cats homozygous for A31P mutation in the MYPBC3 gene and 6 wild-type cats without the A31P mutation. MethodsEx vivo study. All cats received clopidogrel (18.75 mg PO q24h) for 14 days. Before and after clopidogrel treatment, adenosine diphosphate (ADP)-induced P-selectin expression was evaluated. ADP- and thrombin-induced platelet aggregation was measured by optical aggregometry (OA). Platelet pVASP and ADP receptor response index (ARRI) were measured by Western blot analysis. ResultsPlatelet activation from cats with the A31P mutation was significantly (P = .0095) increased [35.55% (18.58-48.55) to 58.90% (24.85-69.90)], in response to ADP. Clopidogrel treatment attenuated ADP-induced P-selectin expression and platelet aggregation. ADP- and PGE(1)-treated platelets had a similar level of pVASP as PGE(1)-treated platelets after clopidogrel treatment. Clopidogrel administration resulted in significantly lower ARRI [24.13% (12.46-35.50) to 11.30% (-7.383 to 23.27)] (P = .017). Two of 13 cats were nonresponders based on OA and flow cytometry. Conclusion and Clinical ImportanceClopidogrel is effective at attenuating platelet activation and aggregation in some cats. Cats with A31P mutation had increased platelet activation relative to the variable response seen in wild-type cats.

One of the challenges of data mining is finding hyper-parameters for a learning algorithm that will produce the best model for a given dataset. Hyper-parameter optimization automates this process, but it can still take significant time. It has been found that hyperparameter optimization does not always result in induced models with significant improvement over default hyper-parameters, yet no systematic analysis of the role of hyper-parameter optimization in machine learning has been conducted. We propose the use of meta-learning to inform the decision to optimize hyper-parameters based on whether default hyper-parameter performance can be surpassed in a given amount of time. We will build a base of metaknowledge, through a series of experiments, to build predictive models that will assist in the decision process.

The research is specifically concerned with the notion of the military masque as a projected extension of the history of masqueing behaviour evident in gay men's attire.The creative outcome of the project is a collection of five interchangeable masques, an animated poetic work and a series of photographic images.This exegesis therefore, seeks to contextualise the created artifacts. In doing this it posits a historical and critical framework that considers the hyper-masculine1 and its relationship to gay men's masqueing.21 In this exegesis hyper masculinity is taken to mean an exaggeration of stereotypical male beliefs and behaviors through an emphasis on virility, strength and aggression and dress codification.2 Frye (1957), in his Anatomy of criticism offers a useful definition of masque as I frame it in this thesis. The term may be understood as "a species of drama in which spectacle plays an important role and in which the characters tend to be, or become aspects of human personality, rather than independent characters" (pp. 365-7). In this respect the masque is something donned that presents a decodable identity extra to, or other than the actual personality of the wearer.

This study is based on the viewpoint of global commodity chains(GCC), to discover the network activities of bicycle industry in Taiwan. But, due to the keen competition , the phenomenon of ¡uHyper-archy competition¡vemerge in bicycle industry . The so called¡uHyper-archy competition¡vindicate that parts factories skip the middle stratum of industry and with the result to promote their competitiveness ; or tighten the original network activities of cooperation , to advance the reachness and richness of information .Namely , to break down the original line-type supply chain relationship of the bicycle industry , transcend the limits of hierarchy and to develop more complete and more diversify network relationship . For this reason , this study focus on the cause and effect of ¡uHyper-archy competition¡v, and to generalize some suggestions to the future.

The research is specifically concerned with the notion of the military masque as a projected extension of the history of masqueing behaviour evident in gay men's attire.The creative outcome of the project is a collection of five interchangeable masques, an animated poetic work and a series of photographic images.This exegesis therefore, seeks to contextualise the created artifacts. In doing this it posits a historical and critical framework that considers the hyper-masculine1 and its relationship to gay men's masqueing.21 In this exegesis hyper masculinity is taken to mean an exaggeration of stereotypical male beliefs and behaviors through an emphasis on virility, strength and aggression and dress codification.2 Frye (1957), in his Anatomy of criticism offers a useful definition of masque as I frame it in this thesis. The term may be understood as "a species of drama in which spectacle plays an important role and in which the characters tend to be, or become aspects of human personality, rather than independent characters" (pp. 365-7). In this respect the masque is something donned that presents a decodable identity extra to, or other than the actual personality of the wearer.

>Magister Scientiae - MSc / The Namib Desert is a hyper-arid, coastal desert with limited bioavailable water and nutrients; characteristics which collectively impose constraints on edaphic microbial communities. Several studies in the Namib Desert have investigated changes in soil microbial communities across space. However, the temporal variation of edaphic bacterial community in response to seasonal microenvironmental variation in the Namib Desert gravel plains has never been investigated in situ.The edaphic bacterial community dynamics were evaluated over short (57 days) and long-term (1 year) sampling intervals using an extensive sampling strategy in combination with community fingerprinting by T-RFLP analyses and microenvironmental characterization. The short-term study was conducted on three distinct locations in the Namib Desert gravel plains. Soil bacterial communities were found to be more similar within habitats than between habitats, with the differences likely shaped by soil pH. These findings are consistent with the concept of habitat filtering.Investigation of edaphic bacterial communities over 1 year in an 8100 m2 sampling site revealed seasonal patterns of variation in community structure. Soil moisture,phosphorus, potassium and magnesium were identified as significant abiotic drivers of community temporal dynamics. β diversity was found to increase over time, while the environment remained relatively static. These findings support previous observations that desert communities are likely structured by stochastic and deterministic processes.Taken together, these findings advance understanding of temporal variation of edaphic communities in the Namib Desert.

This thesis presents the experimental studies of the magnetic and hyperfine interaction properties of four novel Fe-based superconductors (ThFeAsN, CsEuFe4As4, Rb1-δEuFe4As4, and EuFe0.97Ni0.03As2) and one new non-superconducting compound (EuFeAs2). It is supplemented by ab-initio calculations of the electronic structure and magnetism of the three superconductors. The experimental studies are based on the results of x-ray diffraction, magnetic susceptibility, magnetization, and 57Fe and 151Eu Mössbauer spectroscopy measurements. The superconductor ThFeAsN crystallizes in the tetragonal space group P4/nmm with the lattice parameters a = 4.0356(1) Å and c = 8.5286(1) Å. It is shown that there is no magnetic order of the Fe magnetic moments down to 2.0 K. We suggest that nonappearance of Fe magnetism in ThFeAsN may be because of an internal uniaxial chemical pressure whose presence is manifested by the unusually small c/a ratio. We provide theoretical evidence for a mixture of ionic and covalent chemical bonding and metallic characteristics. We present a detailed analysis of the calculated energy band structure of ThFeAsN. A quadrupole doublet well describes the shape of the Mössbauer spectra with a small quadrupole splitting that increases with lowering temperature. Good agreement is found between the calculated and extrapolated 0 K quadrupole splitting values. A fair agreement is noted between the experimental Debye temperature 332(2) K and 370 K of the calculated one. We show that the superconductor CsEuFe4As4 crystallizes in the tetragonal space group P4/mmm with the lattice parameters a = 3.8956(1) Å and c = 13.6628(5) Å. We show that the Fe atoms carry no magnetic moment down to 2.1 K and that the ferromagnetic order is related to the Eu magnetic moments. We establish that the Curie temperature Tc = 15.97(8) K found from the temperature dependence of the hyperfine magnetic field at 151Eu nuclei is well-matched with the temperature dependence of the transferred hyperfine magnetic field at 57Fe nuclei that is produced by the ferromagnetically ordered Eu sublattice. The magnetic moments of the Eu atoms are shown to be perpendicular to the crystallographic c-axis. The T 3⁄2 power-law perfectly describes the temperature dependence of the principal component of the electric field gradient tensor, both at Fe and Eu sites. The calculated and the measured parameters of the hyperfine-interaction are in excellent agreement with each other. We determine that the Debye temperature of CsEuFe4As4 is 295(3) K. Ab-initio calculations suggest a mixture of ionic, covalent, and metallic bonding between the constituent atoms in the CsEuFe4As4 superconductor. We confirm that the strongly localized Eu f states are the origin of the magnetic moment of CsEuFe4As4, in agreement with the experimental results. We show that an almost zero magnetic moment carried by the Fe atoms is caused by the spin-up and spin-down states' apparent symmetry. We show that the Fermi surfaces have hole-like and electron-like pockets located at the center and corners of the Brillouin zone, respectively. The superconductor Rb1-δEuFe4As4 crystallizes in the tetragonal space group P4/mmm with the lattice parameters a = 3.8849(1) Å and c = 13.3370(3) Å. We show that the Fe atoms carry no magnetic moment down to 2.1 K and that the ferromagnetic order is associated solely with the Eu magnetic moments. The Curie temperature Tc = 16.54(8) K is found from the temperature dependence of both the hyperfine magnetic field at 151Eu nuclei and the transferred hyperfine magnetic field at 57Fe nuclei induced by the ferromagnetically ordered Eu sublattice. We find that the Eu magnetic moments lie in the ab plane. It is observed that the temperature dependence of the principal component of the electric field gradient tensor, at both Fe and Eu sites, is well described by a T3⁄2 power-law relation. There is good agreement between the calculated and measured parameters of the hyperfine-interaction. We determine that the Debye temperature of Rb1-δEuFe4As4 is 391(8) K. Ab-initio calculations indicate the presence of a mixture of ionic, covalent, and metallic bonding between the constituent atoms in the RbEuFe4As4 superconductor. We show that the magnetic moment of RbEuFe4As4 is mainly a result of the strongly localized Eu f states. It is shown that an almost zero magnetic moment carried by the Fe atoms originates from an apparent symmetry of the spin-up and spin-down states. We show that the electrical and chemical properties of RbEuFe4As4 are closely associated with the presence of the Fe 3d states in the Fermi energy region. The Fermi surfaces display hole-like and electron-like pockets, respectively, at the center and corners of the Brillouin zone. We find that in both the EuFeAs2 compound and 14 K superconductor EuFe0.97Ni0.03As2 the antiferromagnetic ordering of the Fe sublattice is of a spin-density-wave type with the Néel temperatures and Fe saturation magnetic moments of 106.2(1.9) K, 0.78(1) μB and 56.6(2.2) K, 0.47(1) μB, respectively. We show that the Néel temperatures and the saturation hyperfine magnetic fields in the two compounds with the antiferromagnetically ordered Eu sublattice are 44.4(5) K, 294.2(7) kOe and 43.5(1) K, 290.5(1) kOe respectively. The 3% substitution of Fe by Ni in EuFeAs2, aside from producing superconductivity in EuFe0.97Ni0.03As2, radically reduces the strength of magnetism of the Fe sublattice and has nearly no impact on the magnetism of the Eu sublattice. The appearance of antiferromagnetically ordered Fe and Eu sublattices in EuFe0.97Ni0.03As2 verifies that superconductivity and magnetism coexist in this compond. The growth of the magnitude of the main component of the electric field gradient tensor, at both Fe and Eu sites, with reducing temperature, is well described by a T3⁄2 power-law relation. We determine the Debye temperatures of EuFeAs2, EuFe0.97Ni0.03As2, and the FeAs2 impurity phase to be 355(18), 428(14), and 594(25) K, respectively. In summary, for all of the studied compounds, there is no magnetic ordering associated with iron sub-lattices in the ThFeAsN, CsEuFe4As4, and Rb1-δEuFe4As4 compounds. The iron sublattice is magnetically ordered in the EuFeAs2 and the EuFe0.97Ni0.03As2 superconductor. There is a coexistence of magnetism and superconductivity associated with europium in the CsEuFe4As4, Rb1-δEuFe4As4, EuFe0.97Ni0.03As2 compounds. There is a good agreement between the calculated and the measured hyperfine and magnetic parameters for most studied compounds.

Ce travail est dédié à la résolution de plusieurs problèmes de grand intérêt en traitement d’images : segmentation, choix de modèle et estimation de paramètres, pour le cas spécifique d’images texturées indirectement observées (convoluées et bruitées). Dans ce contexte, les contributions de cette thèse portent sur trois plans différents : modéle, méthode et algorithmique.Du point de vue modélisation de la texture, un nouveaumodèle non-gaussien est proposé. Ce modèle est défini dans le domaine de Fourier et consiste en un mélange de Gaussiennes avec une Densité Spectrale de Puissance paramétrique.Du point de vueméthodologique, la contribution est triple –troisméthodes Bayésiennes pour résoudre de manière :–optimale–non-supervisée–des problèmes inverses en imagerie dans le contexte d’images texturées ndirectement observées, problèmes pas abordés dans la littérature jusqu’à présent.Plus spécifiquement,1. la première méthode réalise la déconvolution myope non-supervisée et l’estimation des paramètres de la texture,2. la deuxième méthode est dédiée à la déconvolution non-supervisée, le choix de modèle et l’estimation des paramètres de la texture et, finalement,3. la troisième méthode déconvolue et segmente une image composée de plusieurs régions texturées, en estimant au même temps les hyperparamètres (niveau du signal et niveau du bruit) et les paramètres de chaque texture.La contribution sur le plan algorithmique est représentée par une nouvelle version rapide de l’algorithme Metropolis-Hastings. Cet algorithme est basé sur une loi de proposition directionnelle contenant le terme de la ”direction de Newton”. Ce terme permet une exploration rapide et efficace de l’espace des paramètres et, de ce fait, accélère la convergence. / This thesis is addressing a series of inverse problems of major importance in the fieldof image processing (image segmentation, model choice, parameter estimation, deconvolution)in the context of textured images. In all of the aforementioned problems theobservations are indirect, i.e., the textured images are affected by a blur and by noise. Thecontributions of this work belong to three main classes: modeling, methodological andalgorithmic. From the modeling standpoint, the contribution consists in the development of a newnon-Gaussian model for textures. The Fourier coefficients of the textured images are modeledby a Scale Mixture of Gaussians Random Field. The Power Spectral Density of thetexture has a parametric form, driven by a set of parameters that encode the texture characteristics.The methodological contribution is threefold and consists in solving three image processingproblems that have not been tackled so far in the context of indirect observationsof textured images. All the proposed methods are Bayesian and are based on the exploitingthe information encoded in the a posteriori law. The first method that is proposed is devotedto the myopic deconvolution of a textured image and the estimation of its parameters.The second method achieves joint model selection and model parameters estimation froman indirect observation of a textured image. Finally, the third method addresses the problemof joint deconvolution and segmentation of an image composed of several texturedregions, while estimating at the same time the parameters of each constituent texture.Last, but not least, the algorithmic contribution is represented by the development ofa new efficient version of the Metropolis Hastings algorithm, with a directional componentof the proposal function based on the”Newton direction” and the Fisher informationmatrix. This particular directional component allows for an efficient exploration of theparameter space and, consequently, increases the convergence speed of the algorithm.To summarize, this work presents a series of methods to solve three image processingproblems in the context of blurry and noisy textured images. Moreover, we present twoconnected contributions, one regarding the texture models andone meant to enhance theperformances of the samplers employed for all of the three methods.

Les matériaux ferroélectriques possédant des propriétés diélectriques géantes font l’objet d’une grande attention scientifique, en grande partie à cause de leur utilisation et potentialités futures dans les dispositifs technologiques, en particulier en microélectronique. L’intérêt de ce travail porte sur l’étude des propriétés vibrationnelles de deux systèmes modèles : le relaxeur PbMg1/3Nb2/3O3 (PMN) monocristallin, et des nano-céramiques de SrTiO3 de tailles de grains contrôlées. Les travaux ont été menés essentiellement par une technique non-linéaire optique originale, la diffusion hyper-Raman (HR) de la lumière, et une attention particulière a été portée aux vibrations de basse fréquence. Des modèles structuraux pu être développés pour relier les signatures spectrales aux propriétés diélectriques de ses systèmes.Dans un premier temps, la spectroscopie hyper-Raman a été poussée à ses limites et a permis d’aboutir à une description convaincante de la dynamique de la polarisation électrique de PMN dans le domaine THz et ce, sur une gamme de température couvrant l’ensemble des différents états relaxeurs. L’hypothèse très répandue mettant en avant l’existence de deux modes mous polaires a ainsi pu être exclue. Les anomalies spectrales à haute température s’expliquent par un couplage entre un mode mou ferroélectrique unique et une vibration non-polaire dont le comportement est indépendant de la température. En refroidissant, l’éclatement du mode mou ferroélectrique révèle la formation d’une anisotropie polaire en dessous de 400-500 K. L’ensemble des modifications spectrales a été capturé dans un modèle simple qui rend également compte de la dépendance en température de la permittivité diélectrique.Dans une seconde partie, les expériences hyper-Raman ont été menées dans deux céramiques de titanate de strontium (SrTiO3) possédant des tailles de grains différentes, 80 nm et 150 nm. L’avantage de la diffusion hyper-Raman pour cette étude est sa propension à sonder les réponses spectrales individuelles du coeur et de la coquille des grains, alors que les techniques usuelles d’absorption infrarouge sondent un milieu effectif moyen. L’analyse spectrale révèle des propriétés de grains identiques dans les deux céramiques : même valeur et même dépendance en température de l’épaisseur de la coquille entourant le cœur, et permittivités diélectriques de cœur ainsi que de coquille identiques dans les deux cas. Un modèle structural reliant les propriétés vibrationnelles et la permittivité diélectrique effective confirme l’existence de deux coquilles entourant le cœur des grains.Ces travaux montrent par ailleurs qu’entre 150 nm et 80 nm, la diminution des propriétés diélectriques est principalement liée au rapport des volumes entre le cœur (haute permittivité) et les coquilles (basses permittivités). / Materials that exhibit giant dielectric properties have received a huge amount of attention from the scientific and industrial communities due to their potentialities and applications in technological devices, in particular for microelectronic applications. In this work, we are interested in studying the vibrational properties of a prototypical relaxor single crystal, PbMg1/3Nb2/3O3 (PMN), as well as nanoceramics of SrTiO3 (STO) with controlled grain sizes. The experiments have been mostly performed by hyper-Raman scattering (HRS), an original non-linear inelastic light scattering spectroscopy. Special attention was devoted to low frequency vibrations, and structural models were developed to relate the vibrational signatures to the giant dielectric responses of these systems.HRS spectroscopy was pushed towards its limit and provided a comprehensive picture of the polarization dynamics of PMN in the THz-range within the whole temperature sequence of its characteristic relaxor states. The widespread hypothesis of two paraelectric soft modes is convincingly excluded. The observation of the split ferroelectric mode reveals the local anisotropy below about 400 K. In contrast, the spectral anomalies observed at higher temperatures are explained as due to avoided crossing of the primary polar soft mode with a temperature-independent, non-polar spectral feature. The temperature changes of the vibrational modes involved in the measured fluctuation spectra of PMN were captured in a simple model that accounts for the temperature dependence of the dielectric permittivity as well.On the other hand, HRS experiments were carried-out on STO single crystal and nano-ceramics of different grain sizes, 80nm and 150nm. Contrary to IR-absorption which gives an effective spectral response of the core and the shell(s) constituting the grains, we show that hyper-Raman provides information of the individual core and shell responses. The spectral analysis reveals that except from their volume, the grains in the two ceramics exhibit very similar structures and properties: same value and temperature dependence of the shell thickness surrounding the core, and same dielectric response of the core as well as of the shell in the two samples. Structural models relating the vibrational properties to the effective dielectric permittivity were developed, and confirm that in STO the grains are composed by one core and two surrounding shells. We demonstrate that between 150 nm and 80 nm the decrease of the effective dielectric permittivity with grain size relates mostly to a change in core and shell volume fraction.