Artificial magnetic materials (AMMs) are a type of metamaterials which are engineered to exhibit desirable magnetic properties not found in nature. AMMs are realized by embedding electrically small metallic resonators aligned in parallel planes in a host dielectric medium. In the presence of a magnetic field, an electric current is induced on the inclusions leading to the emergence of an enhanced magnetic response inside the medium at the resonance frequency of the inclusions. AMMs with negative permeability are used to develop single negative, or double negative metamaterials. AMMs with enhanced positive permeability are used to provide magneto-dielectric materials at microwave or optical frequencies where the natural magnetic materials fail to work efficiently. Artificial magnetic materials have proliferating applications in microwave and optical frequency region. Such applications include inversely refracting the light beam, invisibility cloaking, ultra miniaturizing and frequency bandwidth enhancing low profile antennas, planar superlensing, super-sensitive sensing, decoupling proximal high profile antennas, and enhancing solar cells efficiency, among others. AMMs have unique enabling features that allow for these important applications. Fundamental limitations on the performance of artificial magnetic materials have been derived. The first limitation which depends on the generic model of permeability functions expresses that the frequency dispersion in an AMM is limited by the desired operational bandwidth. The other constraints are derived based on the geometrical limitations of inclusions. These limitations are calculated based on a circuit model. Therefore, a formulation for permeability and magnetic susceptibility of the media based on a circuit model is developed. The formulation is in terms of a geometrical parameter that represents the geometrical characteristics of the inclusions such as area, perimeter and curvature, and a physical parameter that represents the physical, structural and fabrication characteristics of the medium. The effect of the newly introduced parameters on the effective permeability of the medium and the magnetic loss tangent are studied. In addition, the constraints and relations are used to methodically design artificial magnetic material meeting specific operational requirements. A novel design methodology based on an introduced analytical formulation for artificial magnetic material with desired properties is implemented. The synthesis methodology is performed in an iterative four-step algorithm. In the first step, the feasibility of the design is tested to meet the fundamental constraints. In consecutive steps, the geometrical and physical factors which are attributed to the area and perimeter of the inclusion are synthesized and calculated. An updated range of the inclusion's area and perimeter is obtained through consecutive iterations. Finally, the outcome of the iterative procedure is checked for geometrical realizability. The strategy behind the design methodology is generic and can be applied to any adopted circuit based model for AMMs. Several generic geometries are introduced to realize any combination of geometrically realizable area and perimeter (s,l) pairs. A realizable geometry is referred to a contour that satisfies Dido's inequality. The generic geometries introduced here can be used to fabricate feasible AMMs. The novel generic geometries not only can be used to enhance magnetic properties, but also they can be configured to provide specific permeability with desired dispersion function over a certain frequency bandwidth with a maximum magnetic loss tangent. The proposed generic geometries are parametric contours with uncorrelated perimeter and area function. Geometries are configured by tuning parameters in order to possess specified perimeter and surface area. The produced contour is considered as the inclusion's shape. The inclusions are accordingly termed Rose curve resonators (RCRs), Corrugated rectangular resonators (CRRs) and Sine oval resonators (SORs). Moreover, the detailed characteristics of the RCR are studied. The RCRs are used as complementary resonators in design of the ground plane in a microstrip stop-band filter, and as the substrate in design of a miniaturized patch antenna. The performance of new designs is compared with the counterpart devices, and the advantages are discussed.

This thesis introduces spatial filtering, which is a technique to extend the time step size beyond the conventional stability limit for the Finite-Difference Time-Domain (FDTD) method, at the expense of transforming field nodes between the spatial domain and the discrete spatial-frequency domain and removing undesired spatial-frequency components at every FDTD update cycle. The spatially-filtered FDTD method is demonstrated to be almost as accurate as and more efficient than the conventional FDTD method via theories and numerical examples. Then, this thesis combines spatial filtering and an existing subgridding scheme to form the spatially-filtered subgridding scheme. The spatially-filtered subgridding scheme is more efficient than existing subgridding schemes because the former allows the time step size used in the dense mesh to be larger than the dense mesh CFL limit. However, trade-offs between accuracy and efficiency are required in complicated structures.

This thesis introduces spatial filtering, which is a technique to extend the time step size beyond the conventional stability limit for the Finite-Difference Time-Domain (FDTD) method, at the expense of transforming field nodes between the spatial domain and the discrete spatial-frequency domain and removing undesired spatial-frequency components at every FDTD update cycle. The spatially-filtered FDTD method is demonstrated to be almost as accurate as and more efficient than the conventional FDTD method via theories and numerical examples. Then, this thesis combines spatial filtering and an existing subgridding scheme to form the spatially-filtered subgridding scheme. The spatially-filtered subgridding scheme is more efficient than existing subgridding schemes because the former allows the time step size used in the dense mesh to be larger than the dense mesh CFL limit. However, trade-offs between accuracy and efficiency are required in complicated structures.

Parmi les paramètres influençant l'inférence d'arbres phylogénétiques, nous nous sommes penchés d'une part sur (i) l'utilisation et l'efficacité de différents marqueurs et (ii) l'influence de la radiation évolutive (la succession rapide d'événements de spéciation) dans la construction d'arbres phylogénétiques et, d'autre part, sur l'applicabilité du modèle de substitution nucléotidique GTR (General Time Reversible).<p><p>La première partie de ce travail étudie l'évolution des cétacés en se basant sur les séquences des génomes mitochondriaux, sur le motif d'insertion de rétroposons SINEs (short interspersed elements) nouvellement isolés et les loci nucléaires de ces derniers. Le choix des cétacés est motivé par la présence, durant leur évolution, de radiations évolutives, qui sont propices au tri différentiel de lignées généalogiques: si des séquences de gènes ou des allèles restent polymorphes entre des événements de spéciations, il est possible, et même probable, d'observer une incompatibilité entre les histoires évolutives de ces marqueurs, malgré que celles-ci soient bien correctes. Nous abordons l'étude du tri différentiel des lignées généalogiques par le biais des SINEs, dont l'insertion aléatoire et irréversible confère à ces marqueurs un risque de convergence particulièrement faible.<p><p>Notre approche multi-marqueur nous permet de reconstruire un arbre robuste à partir duquel nous analysons ces différents marqueurs à l'aide des rapports signal/bruit (la qualité du contenu informatif du marqueur) et effort/signal (les efforts à mettre en oeuvre pour obtenir du signal phylogénétique). Nous discutons également les relations conflictuelles/incorrectes obtenues à partir des différents marqueurs, notamment des motifs d'insertion de SINEs pour lesquels nous décrivons un test objectif nous permettant de différencier le tri différentiel de lignées généalogiques et la convergence.<p><p><p>Les modèles de substitutions nucléotidiques sont à la base de nombreuses méthodes d'inférence phylogénétiques. Parmi ces modèles, le modèle GTR est un des plus complets et des plus utilisés. Waddell and Steel [1997] ont décrit une procédure qui permet d'estimer les distances et les taux instantanés de substitution pour des séquences évoluant selon les hypothèses du modèle GTR. Il existe néanmoins des conditions qui rendent cette procédure, et donc l'utilisation du modèle GTR, inapplicables. <p><p>Nous avons simulé l'évolution de séquences d'ADN le long de 12 arbres caractérisés par un ensemble de conditions biologiquement plausibles (différentes longueurs de branches, des conditions de (non-)homogénéité de la matrice de taux instantanés de substitution et différentes longueurs de séquences). Pour chaque ensemble de conditions, nous avons évalué (i) l'applicabilité du modèle GTR et (ii) la qualité des alignements obtenus à partir des données simulées. <p><p>Nos résultats indiquent que l'inapplicabilité de la procédure de Waddell and Steel [1997] peut effectivement être considérée comme un problème pratique car elle apparaît avant les difficultés d'alignement (étape nécessaire et préalable à toute inférence phylogénétique). La probabilité de cette inapplicabilité dépend du taux de substitution et de la taille des données.<p> / Doctorat en sciences, Spécialisation biologie moléculaire / info:eu-repo/semantics/nonPublished

Modified discrete cosine transform (MDCT) derived from DCT IV has emerged as the most suitable choice for transform domain audio coding applications due to its time domain alias cancellation property and de-correlation capability. In the present research work, we focus on MDCT domain analysis of audio signals for compression and other applications. We have derived algorithms for linear filtering in DCT IV and DST IV domains for symmetric and non-symmetric filter impulse responses. These results are also extended to MDCT and MDST domains which have the special property of time domain alias cancellation. We also derive filtering algorithms for the DCT II and DCT III domains. Comparison with other methods in the literature shows that, the new algorithm developed is computationally MAC efficient. These results are useful for MDCT domain audio processing such as reverb synthesis, without having to reconstruct the time domain signal and then perform the necessary filtering operations. In audio coding, the psychoacoustic model plays a crucial role and is used to estimate the masking thresholds for adaptive bit-allocation. Transparent quality audio coding is possible if the quantization noise is kept below the masking threshold for each frame. In the existing methods, the masking threshold is calculated using the DFT of the signal frame separately for MDCT domain adaptive quantization. We have extended the spectral integration based psychoacoustic model proposed for sinusoidal modeling of audio signals to the MDCT domain. This has been possible because of the detailed analysis of the relation between DFT and MDCT; we interpret the MDCT coefficients as co-sinusoids and then apply the sinusoidal masking model. The validity of the masking threshold so derived is verified through listening tests as well as objective measures. Parametric coding techniques are used for low bit rate encoding of multi-channel audio such as 5.1 format surround audio. In these techniques, the surround channels are synthesized at the receiver using the analysis parameters of the parametric model. We develop algorithms for MDCT domain analysis and synthesis of reverberation. Integrating these ideas, a parametric audio coder is developed in the MDCT domain. For the parameter estimation, we use a novel analysis by synthesis scheme in the MDCT domain which results in better modeling of the spatial audio. The resulting parametric stereo coder is able to synthesize acceptable quality stereo audio from the mono audio channel and a side information of approximately 11 kbps. Further, an experimental audio coder is developed in the MDCT domain incorporating the new psychoacoustic model and the parametric model.

This thesis deals with a simulation of analogue audio effects using the nonlinear models that replace the analogue nonlinear devices in discrete domain. The thesis describes Volterra system model and simplified Volterra system model that can be realized in two ways, either Wiener model, or Hammerstein model. The method for the analysis and modeling of audio and acoustic nonlinear systems is presented in this thesis. This method allows through knowledge of the input swept-sine signal and the response of the analogue nonlinear system to the input signal to determine the coefficients of the discrete nonlinear system. This allows simulating the analogue nonlinear system in discrete domain. The method was first tested and then used successfully for simulation of the analogue nonlinear system in discrete domain. Concretely, it was simulated a musical guitar effect of the type of distortion. Last part of this thesis is devoted a description of VST technology and an implementation of VST plug-in module, which realizations Hammerstein model.

This paper presents parameters of evaluation of acoustic quality of the space. It is divided into parts presenting physical principle of the origin and movement of the acoustic signal, principles of its processing with current technology and properties of the acoustic field. This is followed by an analysis of the musical part and notes on psychoacoustics. The document contains a description of relevant parameters of acoustic spaces and way in which we can reach desired results, including material analysis. The paper mainly focuses on description of relevant parameters of three acoustic spaces which were measured. The last part of the work is a program for elementary acoustical measurement, which can be provided by means of commonly accessible equipment such as a notebook or a personal computer.

Theoretical part of this diploma thesis gives a brief characteristic of human mobile elements (transposons), which represents nearly 50% of human genome. It provides basic transposon clasification and describes types of transposons present in hunam genome, as well as mobilization, activation and regulation mechanisms. The work also deals with the domestication of transposons, describes the ways in which TE contribute to DNA damage and summarizes the diseases caused by mutagenic activity of transposons in the human genome. Conclusion of theoretical part describes next-generation sequencing technologies (NGS). As practical part, data from RNA-seq experimet were analyzed in order to compare differen transposon activity in normal and cancer cells from prostate and colorectal tissues. As like as publicly available sophisticated tools (TopHat), new scripts were created to analyze these data. The results show that cancer cells exhibit overexpression of transposons. This corresponds with the published results and suggests a connection of transposon activation with cancer development.

In this thesis is presented detail design of power part of DC/DC converter and output inverter. This device will serve for creating an artificial network in a family house where it will be used for supplying selected household appliances which are designed for use in AC network. The converter will be supplied with DC voltage. This tension will be obtained from a system of photovoltaic panels. The output voltage will have alternate character and it will be close to the network voltage 230 V/50 Hz. In the introductory part of thesis are discussed possible topologies of converters and output inverters. Subsequently are designed individual parts of supply inverter. In the final part there are shown waveforms of important values and is given a thesis evaluation.

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