Dissertations / Theses on the topic 'Calcium Wave'
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Erickson, Christopher Joseph. "Construction of a Calcium Matter-Wave Interferometer." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2162.pdf.
Full textYork-Andersen, Anna Henrietta. "Investigating the calcium wave and actin dynamics at Drosophila egg activation." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288873.
Full textOehlschläger, Sven, Oliver W. Hakenberg, Michael Fröhner, and Manfred P. Wirth. "Age-Related Changes of Urine Calcium Excretion after Extracorporeal Shock Wave Lithotripsy due to Artificial Renal Calcium Leakage." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-133774.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
Oehlschläger, Sven, Oliver W. Hakenberg, Michael Fröhner, and Manfred P. Wirth. "Age-Related Changes of Urine Calcium Excretion after Extracorporeal Shock Wave Lithotripsy due to Artificial Renal Calcium Leakage." Karger, 2008. https://tud.qucosa.de/id/qucosa%3A27534.
Full textDieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
Ullah, Ghanim. "COMPUTATIONAL MODELING OF CALCIUM SIGNALING FROM THE NANOSCALE TO MULTICELLULAR SYSTEMS." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1160584521.
Full textEdwards, James Roy. "Modelling Chemical Communication in Neuroglia." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2184.
Full textEdwards, James Roy. "Modelling Chemical Communication in Neuroglia." University of Sydney, 2007. http://hdl.handle.net/2123/2184.
Full textIn vivo many forms of glia utilise both intercellular and extracellular pathways in the form of IP3 permeable gap junctions and cytoplasmic ATP diffusion to produce calcium waves. We introduce a model of ATP and Ca2+ waves in clusters of glial cells in which both pathways are included. Through demonstrations of its capacity to replicate the results of existing theoretical models of individual pathways and to simulate experimental observations of retinal glia the validity of the model is confirmed. Characteristics of the waves resulting from the inclusion of both pathways are identified and described.
Higashi, Cristiane. ""Investigação do processo de obtenção de aluminatos de bário e cálcio para construção e caracterização de catodos termiônicos impregnados para aplicação em dispositivos de microondas de potência"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-31052007-150633/.
Full textIn the present work it is described the barium calcium aluminate manufacture processes employed to produce impregnated cathodes to be used in a traveling-wave tube (TWT). The cathodes were developed using a tungsten body impregnated with barium and calcium aluminate with a 5:3:2 proportion (molar). Three different processes were investigated to obtain this material: solid-state reaction, precipitation and crystallization. Thermal analysis, thermogravimetry specifically, supported to determine an adequate preparation procedure (taking into account temperature, time and pirolisys atmosphere). It was verified that the crystallization showed a better result when compared to those investigated (solid-state reaction and precipitation techniques formation temperature is about 1000ºC in hydrogen atmosphere), whereas it presented the lower formation temperature (800ºC) in oxidizing atmosphere (O2). It was used the practical work function distribution theory (PWFD) of Miram to characterize thermionic impregnated cathode. The PWFD curves were used to characterize the barium-calcium aluminate cathode. PWFD curves shown that the aluminate cathode work function is about 2,00 eV.
Nottingham, Mark. "Resonance photo-ionisation mass spectrometry techniques for the analysis of heavy noble gas isotopes in extra-terrestrial samples." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/resonance-photoionisation-mass-spectrometry-techniques-for-the-analysis-of-heavy-noble-gas-isotopes-in-extraterrestrial-samples(93bc14bd-d13f-4d91-ad16-e264754a6e79).html.
Full textFog, Lotte S. "Coherent production of neutral pions on '1'2C and '4'0Ca." Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368746.
Full textHIGASHI, CRISTIANE. "Investigação do processo de obtenção de aluminatos de bário e cálcio para construção e caracterização de catodos termiônicos impregnados para a aplicação em dispositivos de microondas de potência." reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11463.
Full textMade available in DSpace on 2014-10-09T13:57:49Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Zhang, Wenjun. "Waves in mathematical models of intracellular calcium and other excitable systems." Thesis, University of Auckland, 2011. http://hdl.handle.net/2292/14482.
Full textTrafford, Andrew William. "Local and global measurements of intracellular calcium concentration during spontaneous and triggered propagating calcium waves in single rat ventricular myocytes." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307663.
Full textTimofeeva, Yulia. "Oscillations and waves in single- and multi-cellular systems with free calcium." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/33829.
Full textKelly, Douglas Robert. "The effect of extracellular ATP on spontaneous calcium waves in isolated rat cardiomyocytes /." Title page and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09SB/09sbk2963.pdf.
Full textPaković, Srdan. "Contributions to the theory of non diffractive waves and synthesis of metallic Bessel beam/X-wave launchers." Thesis, Rennes 1, 2021. http://www.theses.fr/2021REN1S128.
Full textThis thesis present the author’s contributions to the field of non-diffractive waves. Essentially, non-diffractive waves are electromagnetic beams that radiate localized energy with a variety of potential practical applications. The work presented in this thesis can be divided into two parts. In the first part, a novel concept of synthesizing metallic spline profiled Bessel beam/X-wave launchers has been proposed. First, an ad-hoc tool based on mode matching is presented. The tool is capable of evaluating the S parameters, near-, and far-field radiation patterns of metallic structures with azimuthal symmetry. Then, metallic Bessel beam/X-wave launchers are synthesized using the ad-hoc tool. The concept has been experimentally validated by manufacturing and measuring an X-wave launcher operating in a 75-105 GHz frequency range. The fabricated launcher is the first experimental demonstration of an X-wave launcher at such frequencies. In the second part, we have investigated the use of non-diffractive waves for wireless power transfer. First, the use of Bessel-Gauss beams for WPT is investigated. The superior performance of Bessel-Gauss beams compared to Bessel beams is demonstrated. A Bessel-Gauss launcher has been designed for validating this claim. The power transfer coefficient of the launcher exceeds 50% for distances exceeding its non-diffractive range
Cox, Kimberly Yvonne. "Melatonin modulates intercellular communication among immortalized rat suprachiasmatic nucleus cells." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2436.
Full textBen, Hassan Saïdi Ismaïl. "Numerical simulations of the shock wave-boundary layer interactions." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS390/document.
Full textSituations where an incident shock wave impinges upon a boundary layer are common in the aeronautical and spatial industries. Under certain circumstances (High Mach number, large shock angle...), the interaction between an incident shock wave and a boundary layer may create an unsteady separation bubble. This bubble, as well as the subsequent reflected shock wave, are known to oscillate in a low-frequency streamwise motion. This phenomenon, called the unsteadiness of the shock wave boundary layer interaction (SWBLI), subjects structures to oscillating loads that can lead to damages for the solid structure integrity.The aim of the present work is the unsteady numerical simulation of (SWBLI) in order to contribute to a better understanding of the SWBLI unsteadiness and the physical mechanism causing these low frequency oscillations of the interaction zone.To perform this study, an original numerical approach is used. The one step Finite Volume approach relies on the discretization of the convective fluxes of the Navier Stokes equations using the OSMP scheme developed up to the 7-th order both in space and time, the viscous fluxes being discretized using a standard centered Finite-Difference scheme. A Monotonicity-Preserving (MP) constraint is employed as a shock capturing procedure. The validation of this approach demonstrates the correct accuracy of the OSMP scheme to predict turbulent features and the great efficiency of the MP procedure to capture discontinuities without spoiling the solution and with an almost negligible additional cost. It is also shown that the use of the highest order tested of the OSMP scheme is relevant in term of simulation time and accuracy compromise. Moreover, an order of accuracy higher than 2-nd order for approximating the diffusive fluxes seems to have a negligible influence on the solution for such relatively high Reynolds numbers.By simulating the 3D unsteady interaction between a laminar boundary layer and an incident shock wave, we suppress the suspected influence of the large turbulent structures of the boundary layer on the SWBLI unsteadiness, the only remaining suspected cause of unsteadiness being the dynamics of the separation bubble. Results show that only the reattachment point oscillates at low frequencies characteristic of the breathing of the separation bubble. The separation point of the recirculation bubble and the foot of the reflected shock wave have a fixed location along the flat plate with respect to time. It shows that, in this configuration, the SWBLI unsteadiness is not observed.In order to reproduce and analyse the SWBLI unsteadiness, the simulation of a shock wave turbulent boundary layer interaction (SWTBLI) is performed. A Synthetic Eddy Method (SEM), adapted to compressible flows, has been developed and used at the inlet of the simulation domain for initiating the turbulent boundary layer without prohibitive additional computational costs. Analyses of the results are performed using, among others, the snapshot Proper Orthogonal Decomposition (POD) technique. For this simulation, the SWBLI unsteadiness has been observed. Results suggest that the dominant flapping mode of the recirculation bubble occurs at medium frequency. These cycles of successive enlargement and shrinkage of the separated zone are shown to be irregular in time, the maximum size of the recirculation bubble being submitted to discrepancies between successive cycles. This behaviour of the separation bubble is responsible for a low frequency temporal modulation of the amplitude of the separation and reattachment point motions and thus for the low frequency breathing of the separation bubble. These results tend to suggest that the SWBLI unsteadiness is related to this low frequency dynamics of the recirculation bubble; the oscillations of the reflected shocks foot being in phase with the motion of the separation point
Almeida, Joseany de Moraes Santos. "PROCEDIMENTO ELETROANALÍTICO PARA DETERMINAÇÃO DE CÁLCIO EM BIODIESEL." Universidade Federal do Maranhão, 2013. http://tedebc.ufma.br:8080/jspui/handle/tede/980.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
Metal traces are often detected in biodiesel samples due to its presence in the raw materials or solubilization during its manufacturing. Thus, this work aims to propose an electroanalytical methodology for the direct determination of Ca²⁺ in biodiesel using with a glassy carbon electrode. The metal quantification was developed according to Anodic Stripping Voltammetry Mode square-wave (SWASV) technique applying EDTA as the complexing agent. Thus, all samples were pretreated according to wet acid digestion processing and microwave radiation. Therefore, a solution of 4 mL of ultrapure nitric acid (HNO₃), 2 mL of hydrogen peroxide (H₂O₂) and 1 mL deionized water were added to 300 mg sample of biodiesel. Later, such mixtures was thermal treated at 90 °C using 300 W (10 min) and 450 W (5 min) of microwave radiations. The analytical determinations were carried out using ammonium buffer (0.01 mol Lˉ¹, pH = 9.4) as supporting electrolyte and EDTA (1x10ˉ² mol Lˉ¹) as ligand. The optimized voltammetric conditions were EDEP = -1000 mV; tpre = 120 s; Frequency = 30 Hz; Amplitude = 100 mV and ΔEstep = 15 mV. The accuracy was verified by recovery tests. In all cases, the metal quantizations were statistically consistent considering the t-test student for a confidence level of 95%. The CV values were lower than 11%, the recoveries were between 102.9% to 102.4% and the values of the detection limits were 1.9 x 10ˉ⁸ and 1.6 x 10ˉ9 mol Lˉ¹ for the samples, showing good accuracy and sensitivity of the proposed method. The values obtained for the samples ranged from 2.8 x 10ˉ⁸ ± 5.0 x 10ˉ⁸ mol Lˉ¹ and 3.4 x 10ˉ7 ± 5.0 x 10ˉ9 mol Lˉ¹ for Ca²⁺ in evaluated biodiesel.
A presença de metais no biodiesel está diretamente relacionada com a matéria-prima utilizada e também com o processo utilizado para a obtenção do biodiesel. Este trabalho apresenta um procedimento eletroanalítico simples para a determinação direta de Ca2+ em biodiesel com um eletrodo de carbono vítreo. A determinação foi feita com a técnica Voltametria de Redissolução Anódica no modo onda quadrada (SWASV), usando-se o EDTA como agente complexante. As amostras de biodiesel foram submetidas a um processo de digestão ácida por via úmida por radiação, em sistema fechado, com o uso de um microondas. O procedimento para digestão das amostras foi realizado pela adição de 4 mL de ácido nítrico ultrapuro (HNO₃), 2 mL de peróxido de hidrogênio (H₂O₂) e 1 mL de água deionizada em 300 mg de amostra de biodiesel. As amostras foram aquecidas a uma temperatura de 90 oC, durante 10 minutos, em potência de 300 W e 5 minutos em potência de 450 W. As determinações foram feitas utilizando-se tampão amônio (0,01 mol Lˉ¹), pH 9,4, como eletrólito suporte e EDTA 1 x 10ˉ² mol Lˉ¹ como ligante, nas seguintes condições: potencial de deposição (Edep) = -1000 mV; tempo de pré-concentração (tpré) = 120 s; frequência (Freq.) = 30 Hz; amplitude (Amp) =100 mV e potencial de escada (ΔEescada) =15 mV. A exatidão do método foi verificada através de testes de recuperação. Os resultados foram concordantes, estatisticamente, considerando o teste-t de student para um nível de confiança de 95%. Os valores de CV foram menores que 11%, as recuperações foram entre 102,9 % e 102,4 % e os valores dos limites de detecção foram de 1,9 x 10ˉ⁸ e de 1,6 x 10ˉ9 mol Lˉ¹ para as amostras analisadas, mostrando boa exatidão e sensibilidade do método proposto. Os valores obtidos para as amostras analisadas situaram-se entre 2,8 x 10ˉ6 ± 5,0 x 10ˉ⁸ mol Lˉ¹ e 3,4 x 10ˉ7 ± 5,0 x 10ˉ9 mol Lˉ¹ para Ca²⁺ nas amostras de biodiesel.
Whitmer, Deborah Lou. "Spatial and temporal characterizatioin of intercellular calcium waves in longitudinal smooth muscle of guinea pig ileum and distal colon /." abstract and full text PDF (free order & download UNR users only), 2005. http://0-wwwlib.umi.com.innopac.library.unr.edu/dissertations/fullcit/3209122.
Full text"December, 2005." Includes bibliographical references (leaves 194-212). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm.
Gupta, Adarsh Baboo. "Numerical Simulations of the shock wave-boundary layer interaction in complex geometries." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPAST013.
Full textThe objective of the present thesis work is to provide a better insight of the SWBLI unsteadiness due to the low-frequency streamwise oscillations of the separation bubble. To investigate this low frequency motion, DNS of the interaction between the shock wave and laminar boundary layer in complex geometries has been carried out. To perform those simulations, a modified numerical approach for curvilinear coordinate, implemented in an in-house parallel (MPI) Finite-Volume based DNS/LES solver (CHORUS) developed at LIMSI-CNRS is used.The first part of the thesis is the validation of the modified numerical approach. The influence of the mesh distortion has been analyzed from several test cases. The errors introduced by different types of deformation for the three test cases dealing with advection, turbulence, and shock wave were identifiable. The errors created by deformation of the mesh are found comparatively low if the control volumes stay close to a parallelepiped. In some cases, a significant rise has been seen due to the introduction of the non-orthogonality of the mesh.The second part is the validation of code in the framework of supersonic flows around a compression corner which is the core of the present dissertation. The validation studies have been carried out for the case of both inviscid and viscous flows over a compression ramp and the comparison with theoretical as well as numerical data has been presented. This comparison has shown that the results obtained with CHORUS code are in good agreement with the reference data. However, those studies are rather old and a lot of progress has been made in numerical methods for high-speed flow simulations. Unfortunately, there are only a few recent studies concerning simulations or experiments of fully laminar flow around ramps or other complex geometries that could have helped to assess Chorus’ ability to compute such flows. It has then been decided to create our own test case using an extensively tested supersonic flow solver, rhoCentralFoam of the OpenFOAM open-source numerical package. The results obtained provided the difference in the two numerical approaches and allowed us to consider Chorus as validated for DNS of compressible flows with shocks in complex geometries.Consequently, the last chapter deals with the physical analysis of the flow created by a laminar boundary layer developing around two geometries: a classical compression ramp and a compression-expansion ramp. As said earlier, the goal of those simulations was to determine whether the low-frequency oscillations of the recirculation zone can be related to the coherent structures in the incoming boundary layer. The results have demonstrated that, for both configurations, the separation shock IS NOT subjected to longitudinal oscillations. However, when analysing the spectra from probes in the vicinity of the separation point, it has appeared that all the frequency information is contained in those temporal signals. The conclusion of this study is that the absence of oscillations in the laminar case is not, as originally thought, due to the absence of coherent structures in the incoming boundary layer but rather to the fact that, in the laminar case, the separation bubble extent is too large. As a consequence, even if the perturbations that make the bubble oscillate in the turbulent case are present for laminar boundary layer, they are damped in such a way that they are not able to move the shock system and/or the recirculation zone. The next step to this study would be to reduce either the freestream Mach number or the ramp angle in order to have a smaller recirculation bubble and check if the motion appear in that case
Ridoux, Julien. "Contribution au développement d'une méthode de calcul rapide de propagation des ondes de souffle en présence d'obstacles." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066193/document.
Full textThe direct numerical simulation of blast waves (accidental or industrial explosions) is a challenging task due to the wide range of spatial and temporal scales involved. Moreover, in a real environment (topography, urban area …), the blast wave interacts with the geometrical obstacles resulting in reflection, diffraction and waves recombination phenomena. The shape of the front becomes complex, which limits the efficiency of simple empirical methods.This thesis aims at contributing to the development of a fast running method for blast waves propagation in presence of obstacles. This is achieved through the use of simplified hyperbolic models for shock waves propagation such as Geometrical Shock Dynamics (GSD) or Kinematic models. These models describe only the leading shock front. This leads to a drastic reduction of the computational cost, from 5 Euler equations at 3D to a 2D problem with 2 equations. However, the study of the Riemann problem shows that the solution of these models does not always exist in the case of the diffraction over a convex corner. We propose an ad-hoc extension of GSD in order to remove this limitation. The blast effects are also recovered through an empirical law available in free field. From a numerical point of view, a 2D conservative Lagrangian algorithm has been implemented and validated. First comparisons with experimental data show the good behaviour of this new model at nearly free computational cost compared to direct Euler methods
Ould, Ahmed Khalifa Mohamed Abderahmane. "Calcul automatique des deformations de la houle, refraction, diffraction, friction : application a l'etude d'un chenal d'acces portuaire." Nantes, 1987. http://www.theses.fr/1987NANT2055.
Full textMartin, Alexandre. "Calcul de la réponse à la déformation et au champ électrique dans le formalisme "Projector Augmented-Wave". Application au calcul de vitesse du son de matériaux d'intérêt géophysique." Thesis, Lyon, École normale supérieure, 2015. http://www.theses.fr/2015ENSL1034/document.
Full textThe internal composition of our planet is a large topic of study and involves many scientific disciplines. The extreme conditions of pressure and temperature prevailing inside the core (consisting primarily of iron and nickel) and the mantle (consisting mainly of perovskites) make the determination of the exact compositions very difficult. This thesis contributes to recent studies whose aim is to determine more accurately the chemistry of these minerals. Its purpose is the development of a tool for the calculation of seismic wave velocities within methods based on ab-initio simulations. These velocities are calculated from the full elastic tensor, including the atomic relaxation and induced changes in the crystal field. We use the approach of the density functional perturbation theory (DFPT) to eliminate numerical uncertainties induced by conventional methods based on finite differences. We combine this approach with the « Projector Augmented-Wave » (PAW) formalism that takes into account all the electrons of the system with a low computational cost. We apply the method on core and mantle materials and we determine the effects of various lights elements (Si, S, C, O and H) on the seismic wave velocities of pure iron, as well as the effect of aluminum in the perovskite MgSiO3
Issa, Samar. "Méthodes variationnelles : Applications à l'analyse d'image et au modèle de Frenkel-Kontorova." Phd thesis, Université de La Rochelle, 2011. http://tel.archives-ouvertes.fr/tel-00808646.
Full textParikh, Jaimit B. "Theoretical Investigation of Intra- and Inter-cellular Spatiotemporal Calcium Patterns in Microcirculation." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1927.
Full textBramas, Bérenger. "Optimization and parallelization of the boundary element method for the wave equation in time domain." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0022/document.
Full textThe time-domain BEM for the wave equation in acoustics and electromagnetism is used to simulatethe propagation of a wave with a discretization in time. It allows to obtain several frequencydomainresults with one solve. In this thesis, we investigate the implementation of an efficientTD-BEM solver using different approaches. We describe the context of our study and the TD-BEMformulation expressed as a sparse linear system composed of multiple interaction/convolutionmatrices. This system is naturally computed using the sparse matrix-vector product (SpMV). Wework on the limits of the SpMV kernel by looking at the matrix reordering and the behavior of ourSpMV kernels using vectorization (SIMD) on CPUs and an advanced blocking-layout on NvidiaGPUs. We show that this operator is not appropriate for our problem, and we then propose toreorder the original computation to get a special matrix structure. This new structure is called aslice matrix and is computed with a custom matrix/vector product operator. We present an optimizedimplementation of this operator on CPUs and Nvidia GPUs for which we describe advancedblocking schemes. The resulting solver is parallelized with a hybrid strategy above heterogeneousnodes and relies on a new heuristic to balance the work among the processing units. Due tothe quadratic complexity of this matrix approach, we study the use of the fast multipole method(FMM) for our time-domain BEM solver. We investigate the parallelization of the general FMMalgorithm using several paradigms in both shared and distributed memory, and we explain howmodern runtime systems are well-suited to express the FMM computation. Finally, we investigatethe implementation and the parametrization of an FMM kernel specific to our TD-BEM, and weprovide preliminary results
Mattesi, Vanessa. "Propagation des ondes dans un domaine comportant des petites hétérogénéités : modélisation asymptotique et calcul numérique." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3026/document.
Full textIn this thesis, we focus our attention on the modeling of heterogeneities which are smaller than the wavelength. The document is decomposed into two parts : a theoretical one and a numerical one. In the first part, we derive a matched asymptotic expansion composed of a far-field expansion and a near-field expansion. The terms of the far-field expansion are singular solutions of the wave equation whereas the terms of the near-field expansion satisfy quasistatic problems. These expansions are matched in an intermediate region. We justify mathematically this theory by proving error estimates. In the second part, we describe the Discontinuous Galerkin method, a local time stepping method and the implementation of the matched asymptotic method. Numerical simulations illustrate these results
Hristovska, Ines. "Dynamique microgliale en conditions physiologiques : un mécanisme contrôlé par les états de vigilance et l’activité neuronale." Thesis, Lyon, 2019. https://n2t.net/ark:/47881/m60c4v3q.
Full textMicroglia, the resident immune cells of the central nervous system (CNS), were traditionally believed to be set into action only by injury or diseases. Strikingly, in the healthy brain, microglia actively carry out parenchyma patrolling by extending and retracting their ramified processes. These movements are referred to as microglial motility and may be to some extent directed toward synapses. However, motility regulation and the purpose of microglia-spine contacts remain elusive. We thus examined the influence of neuronal activity on microglial motility, morphology and microglia-spine interactions during sleep and wakefulness. We found that microglial motility and morphology are modulated by vigilance states. Microglial processes were found to be attracted by active synapses particularly during wake, whereas sleep downregulates microglial proximity and activity-dependent contact with spines. Microglial contact resulted in increased spine activity which was mainly observed during sleep. Understanding the mechanisms regulating microglial dynamics and microglia-spine interactions across the vigilance states will provide further insights into how microglial cells may be involved in sleep- associated functions such as synaptic homeostasis, learning and memory. Grasping these cellular interactions in physiological conditions is crucial to understand synaptic functioning and alterations when microglia are engaged into their immune functions, a hallmark of most brain pathologies
Gras, Thibaut. "Couplage de méthodes d'éléments finis standards (FEM) et ondulatoires (WFEM) pour le calcul de la réponse vibratoire d'une voie ferrée." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2372/document.
Full textRailway noise is a critical issue concerning environmental noise. At the wheel/rail contact point, both the wheel and the track are dynamically excited and vibrate together to emit the well known rolling noise. The point receptance of the rail and the track decay rates are important quantities to accurately predict wheel-rail noise emission. However, the infinite dimension of the track leads to cumbersome numerical finite-element (FE) models and not adapted to assist the research of innovative solutions. The goals of this thesis are to build an efficient numerical model for calculating the vibration from an infinite railway track, but also to include a central non-periodic part with the aim of testing anti-vibration solutions. The vibration propagation along the track is expressed as a sum of different waves using the WFEM (Wave Finite Element Method). The displacements of a 0.6 m unit cell lead to the computation of the whole track. To reduce the dynamic condensation of this cell, a bi-periodic method is proposed in this thesis. The FEM - WFEM coupling is proposed to easily include elastic supports inside the unit cell. Results show a good correlation between test and calculation. Finally, the model proposed in this thesis was used to test the efficiency of an innovative anti-vibration solution developed within the CERVIFER project. It is a dual mode device which makes the supports softer around the wheel to protect the infrastructure, and stiffer away from the wheel to increase the track decay rates. The numerical results revealed to be really promising, and they will permit to pursue the development of this anti-vibration solution
Delhommeau, Gérard. "Les problemes de diffraction-radiation et de resistance de vagues : etude theorique et resolution numerique par la methode des singularites." Nantes, 1987. http://www.theses.fr/1987NANT2032.
Full textKessentini, Ahmed. "Approche numérique pour le calcul de la matrice de diffusion acoustique : application pour les cas convectifs et non convectifs." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC019/document.
Full textThe guided acoustical propagation is investigated in this work. The propagation of the acoustic waves in a main direction is privileged. A Wave Finite Element method is therefore exploited to extract the wavenumbers. Rigid duct's mode shapes are moreover obtained. For ducts with impedance discontinuities, the scattering matrix can be then calculated through a Finite Element modelling of the lined part. A three dimensional modelling of the lined ducts allows a study of the propagation for the full modes orders, their scattering and the acoustic behaviour of the absorbing materials. The forced responses of various configurations of waveguides with imposed boundary conditions are also calculated. The study is finally extended to the acoustical propagation within waveguides with a uniform mean flow
Clary, Vincent. "Développement d'un modèle simplifié 3D pour le calcul de parcs d'hydroliennes - Validation expérimentale." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAI068/document.
Full textNew projects have recently been launched to build farms of several tidal or river turbines, which are part of the renewable energy systems. The turbine wake interactions in the farm must be considered, as they can affect the power production of the turbines. A steady-state Actuator force model using the RANS equations is developed in the present work to calculate the power production and the flow through arrays of tidal or river Darrieus turbines. It uses detailed three dimensional force distributions depending on the position on the turbine, obtained beforehand by a set of blade-resolved URANS simulations of the turbine. New power coefficient and force coefficient laws depending on the local velocity (flow velocity at the machine position) instead of the upstream velocity are established and appear to be independent from the local turbine blockage in an array. Those laws are used to construct a model that adapt the Actuator force distributions to the local velocity of the flow reaching each turbine, in order to simulate each turbine functioning close to its maximum efficiency point. The model is validated against experimental measurements on a reduced-scale Darrieus turbine. Different farm configurations are simulated and compared to results of the same model adapted in two dimensions. The distances between turbines that are optimizing the farm power production are especially investigated
Perez, Thomas. "Problèmes d'algèbre extérieure liés au calcul de fonctions d'ondes électroniques produits de géminales." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4060.
Full textIn quantum chemistry, the electronic wave functions can be viewed as multivectors, therefore all problems translate into mathematical language thanks to the exterior algebra.We first recall some results related to the exterior and the interior products of the exterior algebra of a Hilbert space, which prove useful for quantum chemistry. We follow by presenting a method to find the annihilator ideal of a multivector, corresponding in physics to the excluded space by the Pauli principle, and this technique will be used in a later chapter.In a second step, we provide a summary of the key notions of the quantum formalism of fermionic systems and their counterpart from the point of view of the exterior algebra. We also recall the main approximation methods based on wave functions in quantum chemistry. We then introduce generalized versions of the concepts of seniority number and ionicity. These generalized numbers count respectively the partially occupied and fully occupied shells for any partition of the orbital space into shells. The Hermitian operators whose eigenspaces correspond to wave functions of definite generalized seniority or ionicity values are built. The generalized seniority numbers afford to establish refined hierarchies of configuration interaction spaces within those of fixed ordinary seniority.In the third and main chapter, we present the way that has led us to propose a new geminal product wave function ansatz where the geminals are not strongly orthogonal but satisfy weaker geometrical constraints to lower the computational effort without sacrificing the indistinguishability of the electrons. Our geometrical constraints translate into simple equations involving the traces of products of geminal matrices. In the simplest non-trivial model, a set of solutions is given by block-diagonal matrices where each block is of size 2x2 and consists of a Pauli matrix or a diagonal matrix, multiplied by a complex parameter to be optimized. With this simplified ansatz for geminals, the number of terms in the calculation of the matrix elements of quantum observables, like the Hamiltonian of the Schrödinger electronic equation, is considerably reduced.Finally, in the last part, we explain the implementation of our geminal product model in the computer code “Tonto”, which is a program and library for quantum crystallography and quantum chemistry written in the “Foo” language. The validity of our code has been tested on the calculation of the electronic energy of hydrogen chains. Moreover, a proof of principle that our ansatz gives significantly more accurate results than the strongly orthogonal geminal method has been established
William-Louis, Mame Jean Pierre. "Etude aérothermodynamique de la propagation des ondes de pression lors de la circulation des trains en tunnels simples ou ramifiés." Valenciennes, 1994. https://ged.uphf.fr/nuxeo/site/esupversions/8a9bc601-5e51-4f33-9b4d-97889ee8f87e.
Full textMokrani, Cyril. "Impacts de vagues déferlantes sur un obstacle vertical. Modèle théorique et calcul numérique des pics de pression." Thesis, Pau, 2012. http://www.theses.fr/2012PAUU3004/document.
Full textNumerical simulations are performed to describe different cases of breaking wave impacts at the wave scale. The main purpose is to assess short duration pressure peak involved in impulsive loads. The academical case of a triangular wedge hitting a vertical wall allows to investigate the origin of pressure peak and connect their magnitudes to the local interface inclination. Theoretical results enable us to derive two semi-empirical laws which show that pressure peaks are very sensitive to angle variations for strong interface inclination, making thus theire assessment difficult. This result is illustrated on a breaking dam case for which mesh size has shown to have a great influence on the incident jet shape, revealing that pressure peak assessment requires to know accurately interface profile. The case of a breaking wave is treated by setting up a coupling approach (VOF / BEM). This method allows to accurately approximate the interface profile at the beginning of the breaking stage. Pressure peaks are in good agreement with the theoretical results for angles lower than 70°. Two differents types of impacts are then treated by applying results from triangular case to breaking wave jet and the influence of interface curvature on pressure peak evolution is studied
Luquet, David. "3D simulation of acoustical shock waves propagation through a turbulent atmosphere. Application to sonic boom." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066021/document.
Full textThis thesis deals with the effects of atmospheric turbulence on the propagation of acoustical shock waves. These effects are of major interest for applications such as sonic boom, buzz saw noise or thunder. A numerical one-way method is developed to model and to simulate three-dimensional nonlinear propagation of acoustical shock waves in a moving heterogeneous medium. It relies on a split-step approach that permits to take into account efficiently the different involved physical mechanisms. To tackle realistic 3D problems (of order of one billion of degree of freedom), the implementation of the method is done using the parallel single program multiple data paradigm. Validity of this method is assessed using multiple test cases. The method is applied to investigate the effects of atmospheric turbulence on sonic boom propagation through the Planetary Boundary Layer. Hence, both under-track boom and boom in the shadow zone are studied for a hypersonic configuration developed in the European project ATLLAS II. Finally, the focusing of weak shock waves on a cusped caustic is simulated. It is the first study of the stability of a nonlinear caustic to flow perturbations to our knowledge
Ritter, Patxi. "Ondes gravitationnelles et calcul de la force propre pour un astre compact en mouvement autour d'un trou noir super-massif." Thesis, Orléans, 2013. http://www.theses.fr/2013ORLE2038/document.
Full textThis thesis focuses on modelling the gravitational waves and the relativistic motion associated to Extreme Mass Ratio Inspiral (EMRI) systems. These systems consist of a stellar mass compact object gravitationally captured by a super-massive black hole. In black hole perturbation theory, we further develop a numerical method which computes waveforms generated by a point mass particle orbiting a Schwarzschild black hole. The Regge-Wheeler-Zerilli wave equation is solved in time domain. The gauge invariant solution is related to the polarisation modes, the energy and the angular momentum carried by the gravitational waves. In reaction to the energy and the moment lost, the trajectory is modified all along. In the MiSaTaQuWa formalism, we compute the self-force acting upon a point particle which is initially at rest, and then falling into a Schwarzschild black hole. We show how this quantity is defined in the Regge-Wheeler gauge by using the mode-sum regularisation technique. We take into account the self-force effect on the motion of the particle by using an iterative and osculating orbit method conceived herein. We quantify the orbital deviation with respect to the geodesic motion, but also the perturbed wave forms and the associated radiated energy
Mahfouf, Ali. "Calcul des coefficients de transport dans des plasmas hors de l'équilibre." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22719/document.
Full textTransport properties at high temperature in gases and/or in plasmas are of very importance in various fields, namely in the field of breaking technology in arc, cutting plasma, welding or burning. Knowledge of transport coefficients is necessary for any modeling involving hydrodynamic equations. As part of the kinetic theory of diluted gas, an approximate solution of the integro-differential Boltzmann equation governing distribution functions was proposed by Chapman-Enskog. Transport coefficients are classically computed using the method of Chapman-Enskog through the collision integrals. In our study we have developed, initially, a numerical code to obtain these collision integral taking into account the singularities that may occur in the calculation of the cross sections relating to interactions between particles forming the gas and/or plasmas. Secondly, we have studied the influence of the choice of parameters of interaction potentials on transport coefficients. Subsequently, we have used the numerical code developed for evaluating and helium plasma transport coefficients by studying the influence of the choice of method for calculating chemical composition on these coefficients. Finally, a simplified model of an interaction between an electromagnetic wave and a helium plasma has been proposed as a direct application of the transport coefficients
Chailan, Romain. "Application of Scientific Computing and Statistical Analysis to address Coastal Hazards." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS168/document.
Full textStudies and management of coastal hazards are of high concerns in our society, since they engage highly valuable economical and ecological stakes. Coastal hazards are generally responding to extreme environmental conditions. The study of these physical phenomena relies on the understanding of such environmental conditions, which are rarely (or even never) observed.In coastal areas, waves are the main source of energy. This energy is responsible of coastal hazards developed at different time-scales, like the submersion or the erosion.The presented work, taking place at the interface between Statistical Analysis, Geophysics and Computer Sciences, aiming at bringing forward tools and methods serving decision makers in charge of the management of such risks.In practice, the proposed solutions answer to the questionings with a consideration of the space dimension rather than only punctual aspects. This approach is more natural considering that environmental phenomena are generally spatial, as the sea-waves fields.The study of extreme realisations of such processes is based on the availability of a representative data set, both in time and space dimensions, allowing to extrapolating information beyond the actual observations. In particular for sea-waves fields, we use numerical simulation on high performance computational clusters (HPC) to product such a data set. The outcome of this work offers many application possibilities.Most notably, we propose from this data set two statistical methodologies, having respective goals of dealing with littoral hazards long-terms questionings (e.g., erosion) and event-scale questionings (e.g., submersion).The first one is based on the application of stochastic models so-called max-stable models, particularly adapted to the study of extreme values in a spatial context. Indeed, additionally to the marginal information, max-stable models allow to take into account the spatial dependence structures of the observed extreme processes. Our results show the interest of this method against the ones neglecting the spatial dependence of these phenomena for risk indices computation.The second approach is a semi-parametric method aiming at simulating extreme waves space-time processes. Those processes, interpreted as storms, are controlled and bi-variate uplifting of already observed extreme episodes. In other words, we create most severe storms than the one already observed. These processes simulated at a controlled intensity may feed littoral physical models in order to describe a very extreme event in both space and time dimensions. They allow helping decision-makers in the anticipation of hazards not yet observed.Finally and from the construction of these extreme scenarios, we introduce a pre-computing paradigm in the goal of providing the decision-makers with a real-time and accurate information in case of a sudden coastal crisis, without performing any physical simulation.This work fits into a growing industrial demand of modelling help. Most notably a need related to the chaining of numerical and statistical models. Consequently, the industrial dimension of this PhD.~is mostly dedicated to the design and development of a prototype modelling platform. This platform aims at systematically using HPC resources to run simulations and easing the chaining of models.Embracing solutions towards questionings related to the management of coastal hazard, this thesis demonstrates the benefits of a research work placed at the interface between several domains. This thesis answers such questionings by providing end-users with cutting-edge methods stemming from each of those domains
Bézier, Guillaume. "Sur l'étude fréquentielle de la propagation des chocs pyrotechniques dans les structures complexes." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2012. http://tel.archives-ouvertes.fr/tel-01044782.
Full textAL, SALEH-MAHROUSSEH SALOUA. "Calcul relativiste, en electrodynamique quantique, de la diffusion compton sur un electron lie." Clermont-Ferrand 2, 1988. http://www.theses.fr/1988CLF21098.
Full textDusson, Geneviève. "Estimation d'erreur pour des problèmes aux valeurs propres linéaires et non-linéaires issus du calcul de structure électronique." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066238/document.
Full textThe objective of this thesis is to provide error bounds for linear and nonlinear eigenvalue problems arising from electronic structure calculation. We focus on ground-state calculations based on Density Functional Theory, including Kohn-Sham models. Our bounds mostly rely on a posteriori error analysis. More precisely, we start by studying a phenomenon of discretization error cancellation for a simple linear eigenvalue problem, for which analytical solutions are available. The mathematical study is based on an a priori analysis for the energy error. Then, we present an a posteriori analysis for the Laplace eigenvalue problem discretized with finite elements. For simple eigenvalues of the Laplace operator and their corresponding eigenvectors , we provide guaranteed, fully computable and efficient error bounds. Thereafter, we focus on nonlinear eigenvalue problems. First, we provide an a posteriori analysis for the Gross-Pitaevskii equation. The error bounds are valid under assumptions that can be numerically checked, and can be separated in two components coming respectively from the discretization and the iterative algorithm used to solve the nonlinear eigenvalue problem. Balancing these error components allows to optimize the computational resources. Second, we present a post-processing method for the Kohn-Sham problem, which improves the accuracy of planewave computations of ground state orbitals at a low computational cost. The post-processed solutions can be used either as a more precise solution of the problem, or used for computing an estimation of the discretization error. This estimation is not guaranteed, but in practice close to the real error
Pan, Cihui. "Diffraction électromagnétique par des réseaux et des surfaces rugueuses aléatoires : mise en œuvre deméthodes hautement efficaces pour la résolution de systèmes aux valeurs propres et de problèmesaux conditions initiales." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLV020/document.
Full textWe study the electromagnetic diffraction by gratings and random rough surfaces. The C-method is an exact method developed for this aim. It is based on Maxwell’s equations under covariant form written in a nonorthogonal coordinate system. The C-method leads to an eigenvalue problem, the solution of which gives the diffracted field.We focus on the numerical aspect of the C-method, trying to develop an efficient application of this exact method. For gratings, we have developed a new version of C-method which leads to a differential system with initial conditions. This new version of C-method can be used to study multilayer gratings with homogeneous medium.We implemented high performance algorithms to the original versions of C-method. Especially, we have developed a specifically designed parallel QR algorithm for the C- method and spectral projection method to solve the eigenvalue problem more efficiently. Experiments have shown that the computation time can be reduced significantly
Gaillard, Pierre. "Calcul numérique des ondes de gravité dans les zones littorales et les aménagements portuaires : [thèse soutenue sur un ensemble de travaux]." Grenoble 1, 1988. http://www.theses.fr/1988GRE10079.
Full textYehya, Yassar. "Propagation des ondes acoustiques dans les conduites cylindriques de révolution." Poitiers, 1988. http://www.theses.fr/1988POIT2275.
Full textEl, Khatib Muammar. "Characterization of metallic and insulating properties of low-dimensional systems." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30198/document.
Full textI carried out a theoretical study to characterize metallic and insulating properties of low-dimensional systems using wave function methods. Low-dimensional systems are particularly important because they allow an understanding that can be extrapolated to higher dimensional systems. We have employed a new tool based on the theory of conductivity of Kohn that we have named: total position-spread tensor (TPS). The TPS is defined as the second moment cumulant of the total position operator: ? = - 2 . The tensor divided by the number of electrons diverges when the wave function is delocalized (high fluctuation of electrons' positions), and it takes finite values for localized ones. In this way, the electrical conductivity is related to the proper delocalization of the wave function. In addition, the tensor can be divided in spin-summed (SS-TPS) and spin-partitioned tensors (SP-TPS). The latter one becomes a powerful tool to the study of strongly correlated systems. In this dissertation, we started to investigate at full configuration interaction (FCI) level diatomic molecules showing different types of bond. The TPS presented a marked maximum before the bond was broken and in the asymptotic limit one recovers the TPS values of isolated atoms (size consistency). For the case of diatomic systems showing avoided-crossing electronic states, the TPS diverges evidencing the high delocalization of the wave function. Therefore, the SS-TPS is capable of monitoring and characterizing molecular wave functions. We considered mixed-valence systems that are often distinguished by a double-well potential energy surface presenting an avoided-crossing. Thus, such a configuration possesses a strongly multireference nature involving at least two states of the same symmetry. Two different systems were investigated: i) two weakly interacting hydrogen dimers that were investigated at Full CI level, and ii) a spiro like molecule where the TPS tensor was evaluated in a CAS-SCF state-averaged wave function using our implementation of the SS- TPS formalism in MOLPRO. We found that the tensor's component in the direction of the electron transfer (ET) shows a marked maximum in the avoided-crossing region, evidencing the presence of a high electron mobility. The formalisms of the SS- and SP-TPS was applied to one dimensional systems composed by three types of half-filled hydrogen chains: i) equally-spaced chains, ii) fixed-bond dimerized chains, and iii) homothetic dimerized chains. Both the SS- and SP-TPS showed different signatures associated to the three types of systems. Equally-spaced chains have metallic wave functions and a high spin delocalization in the strongly correlated regime. In contrast, fixed-bond dimerized chains have an insulating character and a restricted spin delocalization. Finally, homothetic dimerized chains dissociate very quickly which renders them in the insulating state but with a high spin delocalization. We also studied half-filled chains by using the Hubbard and the Heisenberg Hamiltonians. On the one hand, we were able to depict the response of the SS- and SP-TPS by varying the ratio between the hopping and electron-electron repulsion (-t/U parameter) of topological connected sites. On the other hand, the ferromagnetic and anti-ferromagnetic character of the wave functions were evaluated by varying the coupling constant (J) in the strongly correlated systems. A theoretical study of closed polyacenes (PAH) structures was performed at CAS-SCF and NEVPT2 level. Our methodology for choosing the active space using the Hückel Hamiltonian was able to characterize the ground state of the systems that indeed fulfilled the Ovchinnikov rule. Finally, we applied the SS-TPS to understand the nature of the wave functions of these PAHs
Roland, Nicolas. "Modélisation de la transition vers la turbulence d'écoulements en tuyau de fluides rhéofluidifiants par calcul numérique d'ondes non linéaires." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL037N/document.
Full textThe transition to turbulence in pipe flows of shear-thinning fluids is studied theoretically. The method used is the computation of `exact coherent structures' that are tridimensional nonlinear waves. For this purpose a pseudo-spectral Petrov-Galerkin code is developped, which also allows to follow solution branches in the parameter space with continuation methods. This code is validated by recovering already published results in the Newtonian case, and by a consistency test in the non-Newtonian case. A spectral exponential convergence is obtained in all cases. This code is used to seek (guided by recent experimental results) new solutions of fundamental azimuthal wavenumber equal to 1,without success at the time being. On the contrary solutions with a fundamental azimuthal wavenumber equal to 2 and 3 are obtained by continuation from the Newtonian case. The shear-thinning effects induce, in terms of critical Reynolds numbers, a delay for the onset of these waves, as compared with the Newtonian case. This delay is characterized. An analogy is made with various experimental results that show a delay in the transition to turbulence, more precisely, in the onset of `puffs', in non-Newtonian fluids
FUJIMOTO, TALITA G. "Microestrutura e propriedades elétricas e dielétricas do titanato de estrôncio puro e contendo aditivos." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26933.
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O titanato de estrôncio (SrTiO3) possui estrutura cristalina do tipo perovsquita. Materiais com este tipo de estrutura são utilizados para diversas aplicações, tais como, sensores, atuadores, em células a combustível de óxido sólido, entre outros. Devido as suas interessantes propriedades físicas, o SrTiO3 vem sendo intensamente estudado, em especial com a introdução de dopantes. Portanto, neste trabalho foi investigada a influência de diferentes teores de Ca (1; 2,5 e 5% mol) e Pr (0,025; 0,050; 0,075 e 1% mol) na microestrutura e propriedades elétricas e dielétricas do SrTiO3, assim como o material sem aditivos (puro). Os resultados mostram que após a sinterização do SrTiO3 puro, a microestrutura consiste de grãos poligonais com tamanho médio micrométrico, além de texturas lisas e rugosas. A condutividade elétrica das amostras sintetizadas sinterizadas a 1450 e 1500ºC é máxima para 2 horas de patamar. Apenas as amostras de SrTiO3 contendo 1% em mol de Ca apresentam fase única. O tamanho médio de grãos das amostras contendo 1% em mol de Ca é 10,65 ± 0,28 µm e para teores acima deste valor ocorre crescimento significativo dos grãos. As medidas de condutividade elétrica mostraram que as amostras contendo a adição de 1% em mol de Ca possuem maior condutividade dos grãos em relação ao material puro. Para as amostras contendo teores de até 0,075% mol de Pr, pode-se observar alguns grãos lisos e outros rugosos e não há variação considerável do tamanho médio de grãos. As amostras contendo menor teor de Pr (0,025% mol) apresentam maior condutividade dos grãos e contornos de grãos. As amostras de SrTiO3 sintetizado sinterizadas a 1450ºC/10 h apresentaram permissividade elétrica colossal em temperatura ambiente em altas frequências.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
Hureau, Jacques. "La transformation conforme et l'etude numerique d'ecoulements stationnaires ou instationnaires autour d'obstacles avec sillage." Orléans, 1988. http://www.theses.fr/1988ORLE2008.
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