Дисертації з теми "Density fluctuation"
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Côté, Alain C. "Density fluctuation measurements with laser scattering." Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:2580d8c1-32f7-40c6-afe1-14ebde9641f3.
Повний текст джерелаMali, Provash. "Density fluctuation and correlation study of multiperticles production in 28Si-Ag/Br interaction at 14.5A GeV." Thesis, University of North Bengal, 2016. http://hdl.handle.net/123456789/2757.
Повний текст джерелаColonna, Nicola. "Exchange and correlation energy in the adiabatic connection fluctuation-dissipation theory beyond RPA." Doctoral thesis, SISSA, 2014. http://hdl.handle.net/20.500.11767/3863.
Повний текст джерелаXu, Peng Ph D. Massachusetts Institute of Technology. "Polarimetry measurements of current density profile and fluctuation changes during lower hybrid experiments on Alcator C-Mod." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/84391.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (pages 179-186).
As a possible method to achieve steady-state plasma operation in a tokamak fusion reactor, Lower Hybrid Current Drive (LHCD) has been extensively studied on Alcator C-Mod. The measurement of current density profiles (or poloidal magnetic field or safety factor) is essential to the understanding of the LH physics. A polarimeter measures the line-integral of the electron density times the magnetic field parallel to a chord through the plasma, and is capable of deriving the current density profile with multi-chord measurements. A three-chord poloidally viewing far-infrared (FIR) polarimeter has therefore been developed for C-Mod. FIR optics, FIR detectors, electronics and mechanical components were custom designed and fabricated. Various sources of vibrations and systematic errors have been carefully dealt with. A synthetic polarimeter signal has been derived from density profiles from Thomson scattering and magnetic field profiles from EFIT. The polarimeter results confirm that the magnetic field profiles from Kinetic EFIT (with Motional Stark Effect and plasma pressure constraints) is much more accurate than those from normal EFIT (no internal constraints, central safety factor qo~0.9 5) during the LHCD. The polarimeter data were used to constrain qO, and the result shows that the current density profile is flattened, and qo increases to ~2 with strong LHCD. Experiments during LHCD with a plasma density scan, a current scan, and LH power and phase scans have been carried out. The Polarimetry observations confirm the off-axis current drive, and strongly decreasing driven current when the density exceeds a limit of about 1.Ox 102 0/m3 . They also indicate that the driven current is closer to the plasma edge for Ip ~820 kA than for I, ~580 kA, and that lower LH phasing is preferred for higher current drive efficiency. The polarimeter is the first diagnostic to measure core magnetic fluctuations in Alcator C-Mod. These include broadband magnetic fluctuations during EDA H-modes that are suppressed with the application of LH power.
by Peng Xu.
Ph.D.
Soula, Serge. "Influence de l'effet couronne sur le champ electrique mesure au voisinage du sol sous orage." Toulouse 3, 1986. http://www.theses.fr/1986TOU30213.
Повний текст джерелаEl, Dib Georges. "Fibres optiques en verre de borophosphate de niobium pour des applications en optique non linéaire." Electronic Thesis or Diss., Limoges, 2023. http://www.theses.fr/2023LIMO0004.
Повний текст джерелаThe main objectives of this thesis were to develop niobium-rich borophosphate optical glass fibers with improved optical quality and to take advantage of their high nonlinearity for their potential use as waveguide devices in the near infrared. The work presented in this thesis deals with theoretical and practical aspects of glass science. It is based on the niobium-rich borophosphate glass matrix : (100-x) [(0,95 NaPO3 + 0,05 Na2B4O7)] - x Nb2O5 ; where x is the Nb2O5 content (mol%) in the glass. First, a detailed study of the thermal/rheological properties and the drawing of the preforms has been performed. Thanks to this study, a correlation between the composition and the drawing ability of the glasses could be demonstrated. Then the relationship between the glass synthesis method and the optical losses has been studied. We have shown that a new approach eliminating the casting step allows to obtain fibers with significantly lower losses. In a second step, one is interested in exploiting the high nonlinearity of these glasses. We have demonstrated the feasibility of thermal poling treatment on fibers with rectangular cross sections for second harmonic generation. On the other hand, the effects of intense laser pulses propagation in fibers of rectangular core/cladding architectures were investigated, leading to show the ability of these glasses to generate supercontinuum sources up to 2.5 µm
GALASSO, SARA. "Generalization of the Eliashberg equations and Density Functional Theory applied to the analysis of the fundamental properties of iron-based superconductors." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2596360.
Повний текст джерелаXie, Tao. "Hydrodynamic characteristics of gas/liquid/fiber three-phase flows based on objective and minimally-intrusive pressure fluctuation measurements." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-09192004-033703/unrestricted/xie%5Ftao%5F200412%5Fphd.pdf.
Повний текст джерелаD. William Tedder, Committee Member ; Minami Yoda, Committee Member ; Tom McDonough, Committee Member ; Andrei G. Fedorov, Committee Member ; S. Mostafa Ghiaasiaan, Committee Chair ; Seppo Karrila, Committee Member. Includes bibliographical references.
Nguyen, Van Thinh. "Contribution à l'étude de la structure de la turbulence près d'une paroi lisse." Paris 6, 1987. http://www.theses.fr/1987PA066553.
Повний текст джерелаMahmoud, Ali. "Analyseur de spectre à haute résolution : Apllication à la mesure des oscillateurs ultrastables." Besançon, 1989. http://www.theses.fr/1989BESA2004.
Повний текст джерелаBarbosa, Renata da Costa. "Controle postural de idosos em superfícies inclinadas: descritores clássicos e modernos." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4697.
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Understanding how the postural control system is impaired with aging can help identify elderly at risk of falling. In order to study the postural control, center of pressure (CP) behavior can be analyzed. Classical descriptors are commonly used for the CP analysis, however, modern descriptors have been developed aiming to provide more information about the underlying processes involved in the postural control. Aims: Analyze and compare classical and modern descriptors used to analyze the postural control in elderly subjects in quiet standing posture, using data acquired from a force platform in horizontal and inclined surfaces. Methods: The study sample consisted of 17 elderly subjects who remained on a force platform in the upright posture for 70 seconds. The data acquisition was performed with the platform on a horizontal surface and again on a surface inclined at 14 degrees with dorsiflexion and later with plantar flexion of the ankle. For each slope, the procedure was repeated three times with eyes open (EO ) and three times with eyes closed (EC). The initial 10 seconds were discarded and then, CP times series were analyzed in the anteroposterior (AP) and mediolateral (ML) directions. The classical descriptors used were in the time in the frequency domain and the modern descriptors were: Detrended Fluctuations Analysis (DFA), Stabilogram Diffusion Analysis (SDA) and the Sway Density Curve (SDC). Results: In the classical analysis, the results showed significant differences in all comparisons made and, in the modern analysis, the variables provided by the SDA and SDC also showed significant differences between comparisons, however, the DFA did not provide any difference between the conditions. Conclusion: Results provided by the classical variables and by the SDA and the SDC suggest a lower stability of elderly subjects in the inclined surface with dorsiflexion followed by plantar flexion and the eyes closed condition. More studies with the modern descriptors are necessary to better understand their results.
Entender como o sistema de controle postural é comprometido com o processo de envelhecimento pode contribuir na identificação de idosos com risco de quedas. Para estudar o controle postural pode-se analisar o comportamento do Centro de Pressão (CP). Descritores clássicos comumente são utilizados para a análise do CP, no entanto, descritores modernos têm sido desenvolvidos, com o intuito de fornecer mais informações sobre os processos subjacentes ao controle postural. Objetivos: Analisar e comparar descritores clássicos e modernos para análise do controle postural em sujeitos idosos na postura ereta quieta, utilizando dados adquiridos na plataforma de força no plano e com inclinação. Métodos: A amostra do estudo foi composta por 17 indivíduos idosos que permaneceram sobre uma plataforma de força na postura ortostática por 70 segundos. A aquisição dos dados foi realizada com uma plataforma sobre uma superfície horizontal e depois sobre uma superfície inclinada a 14 graus nas posições de flexão dorsal e flexão plantar do tornozelo. Para cada inclinação, o procedimento foi repetido três vezes com os olhos abertos (OA) e três vezes com os olhos fechados (OF). Depois de descartados os 10 s iniciais, foram analisadas as séries temporais do CP na direção anteroposterior (AP) e mediolateral (ML). Foram utilizados alguns descritores clássicos no domínio do tempo e da frequência e os descritores modernos: Detrended Fluctuation Analysis (DFA), Stabilogram Diffusion Analysis (SDA) e pela Sway Density Curve (SDC). Resultados: Na análise clássica os resultados indicaram diferenças significativas em todas as comparações realizadas, na análise moderna, as variáveis fornecidas pela SDA e pela SDC também apresentaram diferenças significativas entre as comparações, porém, a DFA não conseguiu apontar tais diferenças. Conclusão: Os resultados fornecidos pelas variáveis clássicas, SDA e a SDC sugerem uma menor estabilidade de sujeitos idosos na superfície inclinada com flexão dorsal seguida da flexão plantar e na condição de olho fechado. Ainda são necessários a realização de mais estudos utilizando tais descritores para uma melhor compreensão de seus resultados.
Jain, Bhuvnesh. "The evolution of cosmological density fluctuations." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28060.
Повний текст джерелаLumsden, Stuart Leonard. "The statistics and evolution of cosmological density fluctuations." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/28460.
Повний текст джерелаCanavezes, Alexandre Gonzalez da Rocha Silva. "The topology of the density of the universe using PSCz." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314346.
Повний текст джерелаBowles, R. J. "Density profiles and concentration fluctuations in liquid binary mixtures." Thesis, University of East Anglia, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370382.
Повний текст джерелаKao, Han. "Numerical analysis of bottom reverberation and the influence of density fluctuations." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA401355.
Повний текст джерелаThomas, Matthew. "3D full-wave modelling of microwave interactions with plasma density fluctuations." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/20481/.
Повний текст джерелаEllsworth, Jennifer L. "Characterization of low-frequency density fluctuations in dipole-confined laboratory plasmas." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62691.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 161-167).
Low-frequency fluctuations of plasma density, floating potential, ion saturation current, visible light intensity, and edge magnetic field are routinely observed in the Levitated Dipole Experiment (LDX). For the purposes of this thesis, we define low-frequency as W << Wbe where Wbe is the electron bounce frequency. These fluctuations in a laboratory dipole confined plasma lead to turbulence mixing that maintain peaked density profiles. The relationship between the different types of low-frequency fluctuations and plasma density transport is considered. Two 16-channel photodiode arrays were designed and constructed to study the spatial and temporal structure of these fluctuations as part of this dissertation. In addition to the photodiode arrays, a four-channel microwave interferometer is used to estimate the density profile and to measure density fluctuations in the plasma. Several electrostatic probes, including a 24-channel floating probe array, measure fluctuations at the plasma edge and eight Mirnov coils measure magnetic fluctuations. The fluctuations fall into three general categories: broadband, turbulent fluctuations observed during nearly all plasma conditions; quasi-coherent fluctuations with low azimuthal mode numbers and peak frequencies on the order 1 kHz observed during discharges with low neutral pressure; and coherent fluctuations with zero toroidal mode number and peak frequencies on the order of 100 Hz, observed during discharges with moderate neutral fueling. The relationship between time-averaged fluctuation characteristics and plasma parameters are explored. The spatial structure of the fluctuations for several representative shots are discussed. The turbulent fluctuations and concurrent density profiles are compared to quasilinear diffusion of interchange mixing in dipolar plasmas for cases where the fluctuations are random. I show that the quasilinear diffusion equation agrees well with the experimental observations of random fluctuations, supporting the conclusion that interchange mixing is causing inward transport that results in peaked density profiles. For other cases, where nonlinear effects appear to dominate the plasma dynamics, the saturated fluctuation amplitudes are compared to the plasma density profiles.
by Jennifer L. Ellsworth.
Ph.D.
Bitane, Rehab. "Transport and density fluctuations in disordered systems : applications to atmospheric dispersion." Nice, 2012. http://www.theses.fr/2012NICE4079.
Повний текст джерелаThe turbulent transport of particles is an important phenomena which appears in many natural and industrial processes. Understanding its properties, and, in particular, the creation of strong density fluctuations, is fundamental to improve models and refine forecasts. This can lead to significant benefits in issues related to economics, the environmental and health. A Lagrangian study of the tracer pair separation was carried out with the help of high resolution data analysis. This allowed us to point out the weaknesses of the mean-field approaches on which most models are based. For the separation, it is found that the transition from the regime of Batchelor (or ballistic) to that of Richardson (or explosive) occurs at times given by those typical of the turbulent kinetic energy dissipation. It is also found that Richardson’s law can be reinterpreted in terms of diffusive behaviour of the velocity differences. Phenomenological arguments allow us to explain this effect through the decorrelation of the acceleration differences and the stationarity of the kinetic energy transfer ratio at large times. The high-order moments of both separation and velocity are also investigated to address the question of "violent events" in the distribution of the distances. Finally, a one-dimensional mass ejection model is proposed and used to examine the density fluctuations of heavy particles transported by the random environment
Wallace, Marty. "Ion density fluctuations in plasma and their effects on hot electron generation." Thesis, Monterey, California. Naval Postgraduate School, 2002. http://hdl.handle.net/10945/5742.
Повний текст джерелаIn this thesis, high-energy electron generation by stimulated Raman scattering of intense laser light is investigated in computer simulations. These high-energy electrons can be used to produce a high-energy x-ray source for Nuclear Weapons Effects Testing. The simulation results are compared with actual experiments conducted at the Atomic Weapons Establishment in the United Kingdom. The simulations show that the heated electron temperature is significantly lowered and the frequency spectrum of the scattered light is broadened by strong ion density fluctuations in the plasma. These density fluctuations are produced when the Raman scattered light undergoes Brillouin backscattering. Interactive Data Language is also used to analyze the spectrum of Raman scattered light in some recent experiments with the OMEGA laser at the University of Rochester.
Wallace, Martin C. "Ion density fluctuations in plasma and their effects on hot electron generation /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FWallace.pdf.
Повний текст джерелаNewey, Scott-John. "Population fluctuations in mountain hares : a role for parasites? /." Umeå : Dept. of Animal Ecology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200526.pdf.
Повний текст джерелаScherner, Michael J. "The effects of moving electron density fluctuations on time domain reflectometry in plasmas." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-03172010-020634/.
Повний текст джерелаHamdi, Haykel. "Théorie des options et fonctions d'utilité : stratégies de couverture en présence des fluctuations non gaussiennes." Thesis, Paris 2, 2011. http://www.theses.fr/2011PA020006/document.
Повний текст джерелаThe traditional approach of derivatives involves, under certain clearly defined hypothesis, to construct hedging strategies for strictly zero risk. However, in the general case these perfect hedging strategies do not exist, and the theory must be rather based on the idea of risk minimization. In this case, the optimal hedging strategy depends on the amount of risk to be minimized. Under the options approach, we consider here a new measure of risk via the expected utility approach that takes into account both, the moment of order four, which is more sensitive to fluctuations than large variance, and risk aversion of the investor of an option towards risk. Compared to delta hedging, optimization of the variance and maximizing the moment of order four, the hedging strategy, via the expected utilitiy approach, reduces the sensitivy of the hedging approach reported in the underlying asset price. This is likely to reduce the associated transaction costs
Armijo, Julien. "Fluctuations de densité dans des gaz de bosons ultafroids quasi-unidimensionnels." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00601066.
Повний текст джерелаDominguez, Arturo Ph D. Massachusetts Institute of Technology. "Study of density fluctuations and particle transport at the edge of I-mode plasmas." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/79261.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 201-208).
The wide range of plasma parameters available on Alcator C-Mod has led to the accessibility of many regimes of operation. Since its commissioning, C-Mod has accessed the Linear ohmic confinement, Saturated ohmic confinement, L-Mode and ELM-free, ELMy and Enhanced D[alpha] H-Mode regimes. Recently, another novel regime, the IMode, has been identified[1][2][3][4]. I-modes feature the presence of steep H-Mode-like electron and ion temperature gradients at the edge of the plasma with L-Mode-like density profiles. The I-Mode, in contrast to the Hl-mode, shows very weak degradation of energy confinement with increased input power, and routinely reaches H98 > 1 while operating at low edge collisionalities ... making it a good candidate for reactor relevant tokamaks. Also relevant for reactors, this regime can be sustained in steady state for more than -15 energy confinement times without the need for ELMs to regulate particle and impurity confinement. Changes in edge density, temperature and magnetic field fluctuations accompany the L-mode to I-mode transition, with reduction of fluctuations in the 50-150kHz range as well as the appearance of a Weakly Coherent Mode (WCM) in the 200-300kHz range, analogous to the Quasi-Coherent Mode (QCM) characteristic of the Enhanced D[alpha] H-mode. Previous work[4] has established a connection between the midrange fluctuation suppression and reduction in the effective thermal diffusivity, Xye, in the pedestal region. The mechanism in I-mode for maintaining sufficient particle transport to avoid impurity accumulation and instabilities has been unclear. The O-mode reflectometry system has been extensively used for the characterization and detection of the I-mode and the WCM, in part, enhanced by upgrades to the system which enabled the baseband detection of density fluctuations at an array of cutoff locations at the edge of the plasma[5] [6] [7]. Using a novel model, the autopower signals of reflectometry channels detecting the density fluctuations have been decomposed into a broadband component and a WCM component. The latter is then used to estimate the intensity of the WCM. In parallel, the particle transport across the LCFS in I-mode plasmas has been estimated using a volume integrated particle transport model, where ionization source measurements are acquired using D[alpha] profiles measured near the outboard midplane. This model takes into account the anisotropic ionization source density around the periphery of the plasma by introducing an asymmetry factor, [sigma], which is then estimated using a study of I-Mode to H-Mode transitions. The results imply that measurements at the outboard midplane overestimate the surface-averaged influx. Finally, a comparison has been made between the particle flux across the LCFS of the I-mode and the intensity of the WCM, which shows a generally positive correlation between the two. This is supporting evidence that the WCM is, in fact, responsible for maintaining particle and impurity transport across the edge of the I-mode energy transport barrier.
by Arturo Dominguez.
Ph.D.
Tsikata, Sedina. "Small-scale electron density fluctuations in the hall thruster, investigated by collective light scattering." Palaiseau, Ecole polytechnique, 2009. http://tel.archives-ouvertes.fr/docs/00/48/40/27/PDF/thesis.pdf.
Повний текст джерелаAnomalous electron transport across magnetic field lines in the Hall thruster plasma is believed to be due in part to plasma oscillations. Oscillations of frequencies on the order of a few megahertz and of wavelengths on the order of a millimeter have been shown to be likely to lead to transport. Measurements of fluctuations at these length scales is, however, beyond the reach of conventional thruster diagnostics such as probes. This work describes the first application of a specially-designed collective light scattering diagnostic (PRAXIS) to the measurement of electron density fluctuations and the subsequent identification of unstable modes in the thruster plasma. Two main high frequency modes are identified, propagating azimuthally and axially, of millimetric length scales and megahertz frequencies. The propagation directions and angular openings of the modes are determined. The azimuthallypropagating mode, believed to be responsible for transport, is shown to have wave vector components antiparallel to the magnetic field and parallel to the electric field, and to propagate within an extremely limited region. The axially-propagating mode is shown to have features closely related to the ion beam velocity and divergence. The electron density fluctuation level is calculated and is associated with a high electric field amplitude. The experiments, confirming a number of predictions arising from linear kinetic theory, also provide much additional information permitting the improvement and development of models for both modes
Idier, Déborah. "Modélisation d'un système de nucléons : Propriétés statiques et dynamiques ; fluctuations de densité." Nantes, 1993. http://www.theses.fr/1993NANT2018.
Повний текст джерелаHershberger, Craig. "COMPARISON OF THEORETICAL MODELS OF POWER SPECTRAL DENSITY TO THE EXPERIMENTAL VALUE FOR SPECTRUM OF IRRADIANCE FLUCTUATIONS." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2737.
Повний текст джерелаM.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE
Devaux, Nicolas. "Influence d'un cisaillement sur les premiers stades de la cristallisation du polypropylène." Phd thesis, École Nationale Supérieure des Mines de Paris, 2003. http://tel.archives-ouvertes.fr/tel-00274692.
Повний текст джерелаDjoko, Kamwa Ghislain. "Fluctuations supracondictrices dans les conducteurs organiques quasi-1D." Mémoire, Université de Sherbrooke, 2007. http://savoirs.usherbrooke.ca/handle/11143/4778.
Повний текст джерелаCastillo, Bautista Gustavo Emilio. "Order and density fluctuations in the vicinity of a granular solid-liquid-like phase transition." Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/114103.
Повний текст джерелаEsta tesis se dedica al estudio de las fluctuaciones de densidad, orden y de capilaridad en la vecindad de una transición de fase granular tipo sólido-líquido que ocurre en una monocapa granular vibrada de geometría cuasi-bidimensional. En la Parte I introducimos las bases teóricas del trabajo con los conceptos y definiciones que serán usadas para describir, analizar y discutir los resultados exper- imentales más adelante. En el capítulo 1 se repasan los modelos microscópicos más importantes usados para describir la materia granular. Además, se presenta una breve revisión sobre teoría cinética e hidrodinámica granular. El capítulo 2 aborda los conceptos escenciales para entender la teoría de las transiciones de fase, tales como la noción de un parámetro de orden y la definición de exponentes críticos. En la Parte II se presentan en detalle los montajes experimentales usados para estudiar el problema, junto con los métodos experimentales usados, en particular la detección de partículas y la detección de la interfase tipo sólido-líquido. En la Parte III, la cual a su vez está dividida en 3 capítulos, se presentan los resultados. En el capítulo 5 se presenta la descripción estática de la transición y su caracterización en términos de un parámetro de orden. Se muestra que esta transición fuera del equilibrio puede ser de primer o segundo tipo dependiendo de la altura de la celda y la densidad de llenado. Además, ésta se caracteriza por el parámetro de orden orientacional Q4. Cuando la transición resulta ser de segundo orden, la longitud de correlación asociada ξ4, el tiempo de relajación τ4, la susceptibilidad estática de Q4, la función de correlación de pares de Q4, y la amplitud del parámetro de orden obedecen leyes de potencias críticas, con saturaciones debido a efectos de tamaño finito. Con esto, la transición continua presenta un comportamiento crítico, con exponente dinámico z consistente con el modelo C de la teoría de fenómenos críticos dinámicos. Luego, en el capítulo 6 se presentan los resultados concernientes a las fluctuaciones de la interfase sólido-líquido. En particular se muestra que estas fluctuaciones resultan estar bien descritas por la teoría de ondas capilares, lo que permite medir la tensión superficial γ, y la movilidad M una vez determinada la energía térmica granular. También se presenta el comportamiento de la tensión de superficie como función del parámetro de control Γ, mostrando que para la transición continua esta disminuye a medida que el sistema se acerca al punto crítico, mientras que para el caso de la transición abrupta esta es aproximadamente constante. Finalmente, en el capítulo 7 se presentan los resultados obtenidos a través del estudio de funciones de correlación dinámicas. En particular, se encuentra la presencia de ondas en el sistema y se obtienen la velocidad de fase y de grupo, tanto de las ondas longitudinales como transversales. Las conclusiones y perspectivas para el trabajo futuro son presentadas en el capítulo final.
Miura, Shinichi. "Theoretical studies on density fluctuations and the stability of an excess electron in liquid water." 京都大学 (Kyoto University), 1995. http://hdl.handle.net/2433/160899.
Повний текст джерелаKyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第6121号
理博第1657号
新制||理||921(附属図書館)
UT51-95-V409
京都大学大学院理学研究科化学専攻
(主査)教授 郷 信広, 教授 中原 勝, 教授 志田 忠正
学位規則第4条第1項該当
Wahyuni, Dwiria. "Développements de méthodes de microscopie de fluctuations de fluorescence : application aux mesures de densité de protéines sur substrats et à la caractérisation de processus d'optogénétique." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALY035.
Повний текст джерелаQuantitative analysis in microscopy imaging has always been a challenge. One noticeable quantitative technique is Fluorescence Fluctuation Microscopy, which is a family of analytical tools generally developed for confocal microscopes that takes advantage of the temporal and/or spatial fluctuations of the fluorescence signal emitted by molecules, Firstly, we developed an approach that combines Image Correlation Spectroscopy with photobleaching to better estimate the surface density of immobilized molecules. The model is useful to overcome the limitation of the standard Image Correlation Spectroscopy when applied to systems of molecules with multi-labeling or aggregates. It has been successfully tested on fluorescence beads that exhibit a wide distribution of brightness. The model was then applied to proteins of the extracellular matrix deposited on the substrate and oligomerization of protein in the cell cytoplasm. Secondly, we performed Raster Image Correlation Spectroscopy on CRY2/CIBN optogenetics cells and studied the dynamics of the proteins of the cytoplasmic CRY2 and membranous CIBN proteins. The technique covers a wide range of diffusional processes; thus, it is useful to measure the diffusion constant for both proteins, including a mapping of protein mobility in membrane revealing a different dynamics over the whole area. We also managed to characterize the dissociation process of CRY2/CIBN
Mpho, Mandla. "Effects of environmental and genetic stress on life history and wing fluctuating asymmetry in mosquitoes." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326755.
Повний текст джерелаRONCALLO, LUCA. "Evolutionary spectral model for thunderstorm outflows and application to the analysis of the dynamic response of structures." Doctoral thesis, Università degli studi di Genova, 2022. http://hdl.handle.net/11567/1080956.
Повний текст джерелаHanson, Gregory Richard. "Microwave reflectometry on the advanced toroidal facility to measure density fluctuations and their radial correlation lengths." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/17280.
Повний текст джерелаCundy, Michael E. "Detection and measurement of density fluctuations induced by a magnetohydrodynamic force in a supersonic boundary layer." Connect to this title online, 2005. http://hdl.handle.net/1811/273.
Повний текст джерелаTitle from first page of PDF file. Document formatted into pages; contains 29 p.; also includes graphics (some col.). This research has been supported by the AFOSR under grant F49620-02-1-0164, Phase II SBIR grant F33615-01-C-3112 of Air Vehicles Directorate of AFRL, and by the National Science Foundation (NSF) Division of Plasma Physics. Available online via Ohio State University's Knowledge Bank. Includes bibliographical references (p. 29). Available online via Ohio State University's Knowledge Bank.
Bitane, Rehab. "Transport et Fluctuations de Densité dans les Systèmes Désordonnés: Appliations à la Dispersion Atmophérique." Phd thesis, Université Nice Sophia Antipolis, 2012. http://tel.archives-ouvertes.fr/tel-00944511.
Повний текст джерелаReutlinger, Johannes [Verfasser]. "Topology, “Smile”-Gaps and Level Fluctuations in the Density of States of Superconducting Proximity Systems / Johannes Reutlinger." Konstanz : Bibliothek der Universität Konstanz, 2016. http://d-nb.info/1124490957/34.
Повний текст джерелаLuna, Ricardo, and Hrishikesh Tapse. "An Analysis on the Coverage Distance of LDPC-Coded Free-Space Optical Links." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606240.
Повний текст джерелаWe design irregular Low-Density Parity-Check (LDPC) codes for free-space optical (FSO) channels for different transmitter-receiver link distances and analyze the error performance for different atmospheric conditions. The design considers atmospheric absorption, laser beam divergence, and random intensity fluctuations due to atmospheric turbulence. It is found that, for the same transmit power, a system using the designed codes works over much longer link distances than a system that employs regular LDPC codes. Our analysis is particularly useful for portable optical transceivers and mobile links.
Bianchetti, Morales Rennan. "Density profile reconstruction methods for extraordinary mode reflectometry." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0031/document.
Повний текст джерелаThe goal of this PhD is to improve the data analysis techniques of frequency swept reflectometry for determination of the density profile of fusion plasmas. There has been significant improvements in the last two decades on the hardware design and signal extraction techniques, but the data analysis is lagging behind and require further improvements to meet the required standards for continuous operation in future reactors. The improvements obtained in this thesis on the reconstruction of density profiles provide a better accuracy in a shorter time, even in the presence of a density hole, also enabling sufficiently precise measurements of the properties of turbulence used to validate numerical models, and allowing real-time monitoring of the shape and position of the plasma
Hui, Lam. "The evolution of density fluctuations through reheating in the inflationary universe and gravitational instability in the non-linear regime." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/38413.
Повний текст джерелаPond, Jarrad W. T. "Perturbation analysis of fluctuations in the universe on large scales, including decaying solutions and rotational velocities." Honors in the Major Thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1309.
Повний текст джерелаBachelors
Sciences
Physics
De, Gentile Benoît. "Fluctuations de densité électronique à petite échelle dans un tokamak : aspects statistiques, et liens avec l'activité magnétohydrodynamique." Paris 11, 1987. http://www.theses.fr/1987PA112044.
Повний текст джерелаNemausat, Ruidy. "Etude expérimentale et théorique des fluctuations thermiques quantiques des noyaux par spectroscopies d'absorption X et RMN." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066158/document.
Повний текст джерелаIn this thesis the impact of quantum thermal fluctuations on XANES and solid-state NMR spectra is described using an experimental and theoretical joint study. This project has two components. First, high-quality experimental data are acquired in order to observe and understand the influence of quantum vibrations in light-elements oxides. Second, a theoretical model is set up to reproduce the effects observed experimentally and describe their origin from a fundamental point of view. The developed theoretical approach is based on the density-functional theory. Within the Born-Oppenheimer and quasiharmonic approximations, the quantum thermal fluctuations of nuclei are modeled by generating atomic configurations obeying quantum statistics at finite temperature. The XANES spectra and NMR parameters are subsequently calculated in these configurations and the average results are compared with spectroscopic data at finite temperature. This approach has been validated by a joint theoretical-experimental study conducted in a series of light-element oxides, where the results were found to be in excellent agreement with the original experimental data. In addition, it is shown that the impact of the quantum fluctuations of the nuclei is influenced by the local symmetry of the probed atomic site
Zamoum, Redouane. "Etude théorique des fluctuations de courant de l'admittance et de la densité d'états d'un nano-système en interaction." Phd thesis, Aix-Marseille Université, 2013. http://tel.archives-ouvertes.fr/tel-00881571.
Повний текст джерелаBottolier-Curtet, Hervé. "Réflectométrie hyperfréquence pour la détermination de la densité électronique et de ses fluctuations sur le Tokamak Petula-B." Paris 11, 1986. http://www.theses.fr/1986PA112191.
Повний текст джерелаFábián, Montabert Andrea Fábián Montabert Andrea. "Fluctuations de l'aimantation induites par des courants de haute densité dans des vannes de spin électrodéposées /." [S.l.] : [s.n.], 2004. http://library.epfl.ch/theses/?nr=3093.
Повний текст джерелаTsikata, Sedina. "Fluctuations de densité électronique à petite échelle dans un propulseur à effet Hall, investigué par la méthode de diffusion collective." Phd thesis, Ecole Polytechnique X, 2009. http://tel.archives-ouvertes.fr/tel-00484027.
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