Dissertations / Theses on the topic 'Double diffusion'
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Petrov, Eugene P., Roland G. Winkler, and Petra Schwille. "Diffusion and segmental dynamics of double-stranded DNA." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-190452.
Full textPetrov, Eugene P., Roland G. Winkler, and Petra Schwille. "Diffusion and segmental dynamics of double-stranded DNA." Diffusion fundamentals 11 (2009) 62, S. 1, 2009. https://ul.qucosa.de/id/qucosa%3A14027.
Full textOduro, Isaac. "Tempered Double Fractional Diffusion Model For Option Pricing." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1587641372696034.
Full textSmith, Wendy Marie. "The effects of double-diffusion on a baroclinic vortex." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/59487.
Full textIncludes bibliographical references (leaves 57-59).
Laboratory experiments were performed to study the combined effects of double-diffusion and rotation on an oceanic intrusion. Intrusions are driven across density-compensated fronts by the divergence of the double-diffusive buoyancy flux. The increased momentum transport across a double-diffusive interface, however, acts to oppose the action of the buoyancy flux. Turbulent double-diffusive Ekman layers could be a means of redistributing momentum. A model of an intrusion was made by injecting salt or sugar solution at the surface of a denser layer of sugar or salt solution in a rotating tank to form a baroclinic vortex. The size and shape of the vortex and the velocity structure of the intrusion were measured as functions of time. The double-diffusive vortex spread more quickly and had slower azimuthal velocities than a non-double-diffusive one. This effect increased as the density ratio approached unity. These results indicate that momentum transport across a double-diffusive interface is larger than that across a non-double-diffusive one; thus, the parameterization of friction in an intrusion model should be considered carefully.
by Wendy Marie Smith.
M.S.
Kerr, O. S. "Horizontal effects in double-diffusive convection." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380229.
Full textSt, Laurent Louis C. "Diapycnal advection by double diffusion and turbulence in the ocean." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/69185.
Full textIncludes bibliographical references (leaves 129-139).
Observations of diapycnal mixing rates are examined and related to diapycnal advection for both double-diffusive and turbulent regimes. The role of double-diffusive mixing at the site of the North Atlantic Tracer Release Experiment is considered. The strength of salt-finger mixing is analyzed in terms of the stability parameters for shear and double-diffusive convection, and a nondimensional ratio of the thermal and energy dissipation rates. While the model for turbulence describes most dissipation occurring in high shear, dissipation in low shear is better described by the salt-finger model, and a method for estimating the salt-finger enhancement of the diapycnal haline diffusivity over the thermal diffusivity is proposed. Best agreement between tracer-inferred mixing rates and microstructure based estimates is achieved when the salt-finger enhancement of haline flux is taken into account. The role of turbulence occurring above rough bathymetry in the abyssal Brazil Basin is also considered. The mixing levels along sloping bathymetry exceed the levels observed on ridge crests and canyon floors. Additionally, mixing levels modulate in phase with the spring-neap tidal cycle. A model of the dissipation rate is derived and used to specify the turbulent mixing rate and constrain the diapycnal advection in an inverse model for the steady circulation. The inverse model solution reveals the presence of a secondary circulation with zonal character. These results suggest that mixing in abyssal canyons plays an important role in the mass budget of Antarctic Bottom Water.
by Louis Christopher St. Laurent.
Ph.D.
Chaplin, Jeremiah E. "An inverse model of double diffusive convection in the Beaufort Sea." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FChaplin.pdf.
Full textThesis Advisor(s): Radko, Timour. Second Reader: Schoenstadt, Arthur. "December 2009." Description based on title screen as viewed on February 01, 2010. Author(s) subject terms: Double diffusion, inverse model, 4/3 Flux Law. Includes bibliographical references (p. 69-71). Also available in print.
Beaume, Cédric. "États localisés dans les systèmes fluides : application à la double diffusion." Toulouse 3, 2012. http://thesesups.ups-tlse.fr/1726/.
Full textSpatially localized states are physical solutions with a particular structure in a well-defined region in space that is embedded in a different background. We focus here on such states that are formed when thermal convection is coupled to solutal or Coriolis forcing. Three different physical configurations are studied: doubly diffusive convection with vertical gradients of temperature and concentration in two-dimensional fluid layers, doubly diffusive convection with horizontal gradients in three-dimensional fluid layers and Rayleigh-Bénard convection in the presence of rotation. In each of these cases, spatially localized solutions are computed and analyzed using dynamical systems theory. Our results reveal different variations of snaking, a mechanism observed and analyzed using model equations
Scheifele, Benjamin. "Double diffusion in Powell Lake : new insights from a unique case study." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45107.
Full textAnouar, Khalid. "Rôle de la diffusion moléculaire dans les transferts des masse : application aux milieux à double porosité." Lille 1, 1993. http://www.theses.fr/1993LIL10064.
Full textPradhan, Sudeep S. "The Effect Of Viscosity On The Erosion Of Gradient- Zone In A Laboratory Solar Pond." Thesis, Indian Institute of Science, 2000. https://etd.iisc.ac.in/handle/2005/233.
Full textPradhan, Sudeep S. "The Effect Of Viscosity On The Erosion Of Gradient- Zone In A Laboratory Solar Pond." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/233.
Full textAouadi, Moncef. "Étude d'un point de codimension deux pour le problème de Rayleigh Benard en double diffusion." Nice, 1992. http://www.theses.fr/1992NICE4532.
Full textBu, Tianren. "Option pricing under exponential jump diffusion processes." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/option-pricing-under-exponential-jump-diffusion-processes(0dab0630-b8f8-4ee8-8bf0-8cd0b9b9afc0).html.
Full textMüller, Lars [Verfasser], and Peter [Akademischer Betreuer] Bachert. "Improved Estimation of Microscopic Tissue Parameters by Double Diffusion Encoding and Flow-Compensated Single Diffusion Encoding Magnetic Resonance Imaging / Lars Müller ; Betreuer: Peter Bachert." Heidelberg : Universitätsbibliothek Heidelberg, 2017. http://d-nb.info/117800872X/34.
Full textThyboll, Pettersson Erik. "Charged colloids observed by electrophoretic and diffusion NMR." Doctoral thesis, KTH, Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119.
Full textThe thesis deals partly with methodology including construction
of hardware and new pulse sequences in the field of electrophoretic
NMR, and partly with practical use of ENMR and
diffusion NMR in the investigation of charged colloidal systems.
Several sources of artefacts are investigated, including gas production
at the electrodes, electroosmosis and Joule heating
effects that can cause convection. The electrophoretic double
stimulated-echo pulse sequence is introduced to suppress these
artefacts and to increase the feasible measuring range to higher
electric fields and conductivities.
The interaction between the non-ionic polymer poly(ethylene
oxide) PEO and differently charged surfactants is investigated
using the above mentioned methods. The investigated surfactants
are the anionic sodium dodecyl sulphate (SDS) and
potassium laurate (KC12), the cationic dodecyltrimethylammonium
bromide (CTAB) and the non-ionic octyl β-D-glucoside.
ENMR is also used to investigate two different mixed micelle
systems, with SDS as the charged surfactant component and
dodecyl malono-bis-N-methylglucamide (C12BNMG) respectively
tetra(ethylene oxide) dodecyl ether (C12EO4) as the nonionic
surfactant component. A method to calculate the degree
of counter-ion dissociation, αdissociation, as a function of composition
is demonstrated.
Finally diffusion NMR is used to compare transport dynamics
in gel electrolyte systems based on two differently grafted polymers;
one amphiphilic system containing polymethacrylate
grafted partly with polyethylene oxide and partly with fluorocarbons
and the corresponding nonamphiphilic system grafted
with only polyethylene oxide. Both systems contain the electrolyte
lithium bis(trifluoromethylsulfonyl) imide salt dissolved in
γ-butyrolactone. The results show that the system based on the
amphiphilic polymer has better transport dynamics and therefore
is more suited as material for battery
Alford, Matthew. "Observations of overturning and double diffusive processes in the thermocline : the context of ocean mixing /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9907820.
Full textWells, Mathew Graeme, and mathew@inferno phys tue nl. "Convection, turbulent mixing and salt fingers." The Australian National University. Research School of Earth Sciences, 2001. http://thesis.anu.edu.au./public/adt-ANU20011212.103012.
Full textYahiaoui, Amine. "Simulation numérique de la convection naturelle induite par double diffusion et effet Soret dans une cavité cylindrique concentrique." Cergy-Pontoise, 2007. http://biblioweb.u-cergy.fr/theses/07CERG0382.pdf.
Full textThis thesis reports an analytical and numerical study of the behavior of a binary mixture in confined fluid and porous media. The convective motion is driven by either applying constant fuxes of heat and mass or stant temperatures and concentrations on the vertical walls, while the horizontal ones are impermeable and adiabatic. The thermosolutal convective phenomenon (double diffusive convection, (a = 0) or Soret induced convection (a = 1)) inside the enclosure are described by the Navier Stokes equations, the energy and species conservation equations. Governing parameters of the problem under study are the thermal Rayleigh RT, buoyancy ratio N, Lewis number Le, curvature parameter η, and aspect ratio A. The particular situation where the buoyancy forces induced by the thermal and solutal effects are opposing each other and of equal intensity (N = -1) is considered for the porous case. For this situation a purely diffusive rest state is possible. The linear stability theory is used to predict analytically the critical Rayleigh number for the onset of convection. Also the linear stability of the convective motion, predicted by the parallel fow approximation, is investigated numerically in order to predict the occurrence of Hopf's bifurcation
Rafieivand, Mehrdad. "Etude numérique de la convection de double diffusion en présence de rayonnement en cavité rectangulaire/ par Mehrdad Rafieivand." Poitiers, 1999. http://www.theses.fr/1999POIT2333.
Full textYahiaoui, Amine Hassen Beji. "Simulation numérique de la convection naturelle induite par double diffusion et effet Soret dans une cavité cylindrique concentrique." [S.l.] : [s.n.], 2009. http://biblioweb.u-cergy.fr/theses/07CERG0382.pdf.
Full textThèse soutenue en co-tutelle avec l'Ecole polytechnique de Montréal. Titre provenant de l'écran titre. Bibliogr. f. 134-142.
D'Hernoncourt, Jessica. "Influence of thermal effects and electric fields on fingering of chemical fronts: a theoretical study." Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210607.
Full textIn this context our work aims to understand theoretically in which way a chemical reaction can induce and influence such instabilities in a fluid initially at rest.
To understand the dynamics resulting from the coupling between chemical reactions and hydrodynamical instabilities we use chemical fronts as model systems. These fronts result from the coupling between autocatalytical chemical reactions and diffusion and they allow to create a self-organized interface between the products and the reactants. As during a chemical reaction the density may vary due to solutal and thermal effects, the products and the reactants can have different densities which may trigger convection movements leading to the destabilization of the fronts.
We have in particular studied the influence of the exothermicity of the reaction on the fingering of chemical fronts, focusing first on the influence of heat losses through the walls of the set-up.
These leaks have a marked influence on the dynamics because they affect the temperature profiles and hence the density profiles too. We have also classified the various types of instabilities that may appear dues to solutal and thermal effects. We have found a new type of hydrodynamic instability of statically stable fronts induced by the chemical reaction.
We have furthermore analyzed an isothermal model with two chemical species. If they diffuse at different rates the front can be subject to diffusive instabilities as well. We have shown that the coupling between such a diffusive instability and fingering can trigger complex dynamics. We have eventually studied the influence of an external electric field on the diffusive instabilities and on fingering underlying the possibility to destabilize otherwise stable fronts./
Différents types d'instabilités hydrodynamiques peuvent affecter les interfaces entre deux fluides comme par exemple, une instabilité de Rayleigh-Taylor (ou digitation de densité) quand un fluide plus dense se trouve placé au-dessus d'un fluide moins dense dans le champ de gravité ou des instabilités de double diffusion induites par des différences entre les diffusivités d'un soluté et de la chaleur contenus dans les fluides. Dans ce contexte, notre thèse s'attache à comprendre de manière théorique comment une réaction chimique peut influencer ces instabilités voire les générer dans un fluide initialement au repos. Pour étudier les dynamiques résultant du couplage entre réactions chimiques et instabilités hydrodynamiques, nous utilisons des systèmes modèles: les fronts chimiques de conversion résultant de la compétition entre réactions chimiques autocatalytiques et diffusion créant une interface auto-organisée entre les réactifs et les produits. Comme au cours d'une réaction chimique la densité peut varier par des effets solutaux et thermiques, les produits et les réactifs de densités différentes peuvent générer des mouvements de convection qui conduisent à la déstabilisation des fronts.
Nous avons en particulier étudié l'influence de l'exothermicité de la réaction sur les instabilités de digitation de fronts chimiques, en nous focalisant dans un premier temps sur l'influence des pertes de chaleur par les parois du réacteur.
Ces fuites ont un effet marqué sur les instabilitités car elles affectent les profils de température et donc les profils de densité dans le système. Nous avons également classifié les différentes instabilités qui peuvent apparaître via des changements de densité dûs à des effets thermiques et solutaux et mis en évidence un nouveau type de déstabilisation hydrodynamique de fronts statiquement stables induit par une réaction chimique.
Nous avons ensuite analysé un modèle isotherme impliquant deux espèces chimiques. Si ces dernières diffusent a des vitesses différentes le front peut être sujet à une instabilité diffusive. Nous avons montré qu'un couplage entre une telle instabilité diffusive et de la digitation peut être à l'origine de dynamiques complexes. Nous avons ensuite considéré l'influence d'un champ électrique sur les instabilité diffusives et de digitation en soulignant la possibilié de déstabiliser via ce champ des fronts initialement stables.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Kemppainen, J. (Jukka). "Behaviour of the boundary potentials and boundary integral solution of the time fractional diffusion equation." Doctoral thesis, University of Oulu, 2010. http://urn.fi/urn:isbn:9789514261329.
Full textNadratowska, Natalia Beata, and Damian Prochna. "Option pricing under the double exponential jump-diffusion model by using the Laplace transform : Application to the Nordic market." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-5336.
Full textIn this thesis the double exponential jump-diffusion model is considered and the Laplace transform is used as a method for pricing both plain vanilla and path-dependent options. The evolution of the underlying stock prices are assumed to follow a double exponential jump-diffusion model. To invert the Laplace transform, the Euler algorithm is used. The thesis includes the programme code for European options and the application to the real data. The results show how the Kou model performs on the NASDAQ OMX Stockholm Market in the case of the SEB stock.
González, Arish Tatiana. "Economic disparity yet resulting similarity : the 'double paradox' of Argentina's and Mexico's electric telegraph and telephone diffusion, 1851-1997." Thesis, London School of Economics and Political Science (University of London), 2010. http://etheses.lse.ac.uk/2212/.
Full textMaillet, Perrine. "Structure et croissance de nanotubes de Ge-imogolite simple et double-paroi." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2010. http://tel.archives-ouvertes.fr/tel-00584846.
Full textBonnet, Clément. "L'innovation dans les technologies de l'énergie bas-carbone : analyses théoriques et évaluations empiriques." Thesis, Paris 10, 2016. http://www.theses.fr/2016PA100177/document.
Full textInnovation in low-carbon energy technologies (LCETs) is impeded by externalities on the environment on the one hand, and on knowledge on the other hand. These market failures need to be addressed through public policies. The purpose of this thesis is to investigate the conditions for effectiveness of policies aiming at supporting innovation in LCETs. It does so by having recourse to theoretical analyses in conjunction with empirical assessments. The thesis is structured into five chapters. Chapter 1 questions the need to implement innovation policies specifically dedicated to LCETs — as opposed to neutral innovation policies that do not discriminate between these technologies and other technologies. A review of the economic instruments that have been implemented is proposed and indicates the predominance of a demand-pull approach — over a supply-push approach — to support innovation in LCETs. Chapter 2 evaluates the effects of demand-pull support instruments by conducting a counterfactual analysis to determine the extent to which the diffusion of wind power in six European countries is imputable to these instruments. Chapter 3 develops an econometrical method aiming at providing a robust measure of the produced knowledge that pertains to LCETs. A common latent factor model is used to estimate the quality of inventions that have been patented by six countries between 1980 and 2010 in fifteen low-carbon energy technologies. Chapter 4 revisits the question of the optimal design of a patent system when specifically dedicated to a process invention, whose reward depends on the pricing of environmental externalities. Chapter 5 summarizes our results and articulates key issues and messages
Moussavou, Manel. "Modélisation du transport quantique de transistors double-grille : influence de la contrainte, du matériau et de la diffusion par les phonons." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0353.
Full textThe transistor is the elementary brick of Integrated circuits found in all electronic devices. Years after years the microelectronic industry has enhanced the performances of integrated circuits (speed and energy consumption) by downscaling the transistor. Nowadays besides the transistor’s downscaling, other techniques have been considered to maintain this growth: they are called technological boosters. Mechanical strain or new material, such as germanium (Ge) and III-V semiconductors, to replace Silicon are example of technological boosters. By the means of numerical quantum simulations and modeling, this these work propose a study of the effect of technological boosters on the electric performances of the next generation of transistors
Kim, Sangjoon. "The Development and Characterization of Double Layer Hydrogel for Agricultural and Horticultural Applications." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1279116187.
Full textDupuis, Marc. "Modèles de réactions directes et de pré-équilibre quantique pour la diffusion de nucléons sur des noyaux sphériques." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2006. http://tel.archives-ouvertes.fr/tel-00412169.
Full textNguyen, Phu Tho. "Étude multiphysique du transfert de chlorures dans les bétons insaturés : prédiction de l’initiation de la corrosion des aciers." Thesis, La Rochelle, 2014. http://www.theses.fr/2014LAROS004/document.
Full textThe corrosion of steels in the reinforced concrete structures caused by chlorides is one of the main causes of degradation of the constructions in particular in maritime facade. The prediction of the service life of the constructions towards this pathology requires the understanding of the main mechanisms relating to the chlorides transport especially in the unsaturated materials submitted to the tide or to the salt spray. To improve the works of the literature, the main objectives should be accomplished are : to study the experimental characterization of the electrical double layer (EDL) and to study its influence on the ionic transport ; to research on the temperature effect and the hysteresis effect on the chloride profile ; to examine chloride transfer coupled with corrosion of reinforcement. To reach these objectives, the work is divided into four parts. The first one is dedicated to the theoretical approach of the problem to establish the equations allowing describing the coupling between ionic and hydrothermal transfer to the unsaturated materials. The consideration of the EDL is also clarified. The second part is experiment. It is realized on eco-concretes made on base of slag and fly ash. It consists in quantifying the inputs of the model identified during the first part such as: porosity, gas permeability, chloride diffusion coefficients, pore size distribution, chemical interactions, isotherms of sorption-desorption and the Zeta potential characterizing the EDL. In the third part, the transfer equations translating to the model are numerically resolved. The study of model sensibility according to EDL, the temperature, the water permeability is performed. A comparison between the numerical results (chloride profile) obtained with the model with experimental ones obtained in the case of tidal zone allowed shows the interest to consider the hysteresis effects. Also, it is shown that the EDL effect is significant beyond Zeta potential of 25mV. The last part concerns the study of the coupling between chloride transfer and corrosion of steels. The estimations of the duration of incubation, the loss of section of steel, the times required to cover cracking were examined. The result showed that the use of the law of Fick can underestimate these parameters
Olmedo, Herrero Elena. "Étude des effets non linéaires dans les lasers et amplificateurs de puissance à fibre double gaine dopée Er3+/Yb3+." Phd thesis, Télécom ParisTech, 2003. http://pastel.archives-ouvertes.fr/pastel-00000743.
Full textHocine, Tarek. "Détermination expérimentale de la double couche électrique et étude de son influence sur le transfert des ions chlorure dans les matériaux cimentaires." La Rochelle, 2009. http://www.theses.fr/2009LAROS272.
Full textThe corrosion induced by the penetration of the chloride ions in cement based materials remains one of the major causes of degradation of the structures, their durability is explained by the difficulty which have the aggressive agents to penetrate in the porous medium. This thesis treats the study of the influence of the electrocapillary phenomena through the electric double layer (EDL) on the ionic transfer in general and the transfer of the chloride ions in particular in cement based materials. Several studies on quantification of the EDL of the components of cement (clinker, C3S…) as well as the hydrates, the C-S-H mainly, were carried out, on the other hand, studies concerning cement based materials and their compounds are very few. At first to identify the surface charge of the walls of pores, measurements of zeta potential were performed then analysed on the different cement based materials (cement pastes, mortars and concretes) for various cement classes ; CEM I, II and V as well as aggregates. Then, a study of identification of the microstructure of cement based materials was carried out by the mercury intrusion porosimetry technique. Thereafter, the migration tests were performed on the cement pastes, mortars and concretes. The evolutions of the electrical current are presented and used in order to characterize the transfer of chloride ions within the porous medium. Finally, a one-dimensional numerical model and multi-species based on the Nernst-Plank equation integrating EDL phenomena was developed, the chemical reactivity of the cement based materials is taken into account through the adsorptions isotherms. This model allows simulating the diffusion and migration processes of chloride ions across saturated cement based materials according to the both cases; with and without taking into account of the EDL effect. The theoretical treatment of the EDL was performed from Poisson-Boltzmann theory. The adopted approach to highlight the influence of the electric double layer was to compare experimental chronoamperometry resulting from the migration tests with those simulated
Rouhvand, Bahar. "Vesicle-Protein Diffusion and Interaction Study Using Time Resolved Fluorescence Correlation Spectroscopy." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1503261462042903.
Full textLagadec, Saioa. "Dépression post-AVC : apport d’une double approche de neuroimagerie et enquête en vie quotidienne." Thesis, Bordeaux 2, 2012. http://www.theses.fr/2012BOR21927/document.
Full text30% of stroke survivors will experience Post-Stroke Depression (PSD) that is associated to a poor quality of life. PSD is still under-diagnosed due to the absence of clear diagnostic criteria and its pathophysiology remains unknown. The aim of this study was to identify early imaging and psychiatric risk factors of depression 3 months after stroke. Patients with a first ischemic stroke, without any neurologic and psychiatric history were included. Daily-life symptoms were evaluated using ESM 10 days after stroke. Brain MRI acquisition was performed at 10 days after stroke including DWI, FLAIR/T2, resting state fMRI and anatomical sequences. We explored the association between 1/ the severity of depressive symptoms and MRI data 2/ the severity of depressive symptoms and ESM data 3/ the severity of depressive symptoms measured by ESM and MRI data.Results revealed a modification of the functional connectivity between posterior structures of the DMN (Default Mode Network) and between the middle temporal cortex and the DMN. In the acute phase, depressed patients presented either high fatigue and anhedonia or another profile including high anxiety, negative thoughts and emotional reactivity which is associated to the risk of depression 3 months after stroke. Moreover, we demonstrated that functional connectivity modifications within the DMN and the cerebellum grey matter were respectively associated to emotional reactivity and the frequency of positive and negative thoughts.In conclusion, modifications of the DMN were implicated in the physiopathology of PSD in the same way that major or vascular depression, with a specificity represented by the new contribution of the middle temporal cortex within the DMN. Furthermore, this study suggests that more than a stroke lesion, anterior psychobiological vulnerabilities of an individual patient could mediate PSD occurrence
Pichon, Luc. "Croissance par pulvérisation réactive à double faisceau d'ions et par traitement thermique en plasma d'ammoniac de nitrures de zirconium métalliques et semi-transparents ; caractérisations optiques et structurales." Poitiers, 1999. http://www.theses.fr/1999POIT2259.
Full textAïssaoui, Safae. "Collaborations science-industrie et innovation dans les firmes françaises : impacts et déterminants." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENA022.
Full textThe works presented in this thesis use systems of innovation as an analytical framework and aims to study the effects and determinants of science-industry collaborations. Our empirical approach relies on a combination of statistical and econometric analysis of national data, and exploratory surveys within a given territory. To determine the impact of these collaborations on firms' innovation, we consider two measures of innovation: patenting and innovative performance. Taking into accounts two types of academic collaboration, including collaborations with universities and establishments of higher education and public and nonprofit research organizations, it appears that these collaborations have a significant and positive effect on innovation. On the other hand, determinants of science-industry collaborations are analyzed through two surveys: one covering firms belonging to a technopole, and the other conducted among researchers from a university. Both surveys show that firms collaborate with academic organizations mainly to find solutions to problems they face, while researchers are involved in these collaborations to stay abreast of current issues of economic agents. The results of the first survey establish a mutliscalar nature of science-industry collaborations, which minimize the importance of permanent geographical proximity in favor of a temporary geographical proximity coupled with other types of proximity. The second survey, which focuses on the determinants of researchers' propensity to collaborate, shows that these determinants are different according to the type of collaboration
Krebs, Daniel. "Pricing a basket option when volatility is capped using affinejump-diffusion models." Thesis, KTH, Matematisk statistik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-123395.
Full textLemembre, Alain. "Evolution par convection naturelle d'une stratification formée de deux couches liquides dans un réservoir cylindrique." Châtenay-Malabry, Ecole centrale de Paris, 1999. http://www.theses.fr/1999ECAP0618.
Full textHirata, Silvia. "Stabilité de la convection thermique et / ou solutale en couches fluide et poreuse superposées." Paris 6, 2007. https://tel.archives-ouvertes.fr/tel-00175767.
Full textBordais, Sylvain. "Etude des amplificateurs et lasers 1 µm de forte puissance à base de fibre double gaine dopée Ytterbium." Phd thesis, Université Rennes 1, 2002. http://tel.archives-ouvertes.fr/tel-00002890.
Full textLi, Yiqin. "Approches analytique et expérimentale de la convection naturelle en canal vertical : Application aux double-façades photovoltaïques." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI002/document.
Full textUnder the current energy context, the development of solar energy goes through its large scale development, especially in urban areas. Active and integrated solutions, such as photovoltaic double-skins, allow both the heat recovery for building needs and the exploitation of building envelope as collecting surface. Furthermore, this configuration limits the efficiency loss and the acceleration of ageing process due to overheating of the solar cells. Indeed, in this configuration, the photovoltaic panels are separated from the building by an air channel and the thermally driven flow that develops in the channel helps to evacuate the heat absorbed by the panels. However, the global behaviour of the photovoltaic double-skin is complex and not yet fully understood. This study is part of a scientific project on multi-scale modelling and experimentation of BIPV components. It focuses on the experimentation of the natural convection phenomenon in double-façades. An experimental apparatus developed during C. Daverat's thesis models the double-façade by a vertical channel with wall heating. The working fluid is water so as to avoid radiative heat transfer between walls. The experimental apparatus consists of a 65 cm high vertical channel, with isoflux heating, immersed in a 1.5 m high water tank. The fluid flow is instrumented with measurements of heat flux, wall temperature and velocity. The velocity measurements are made by Particle Image Velocimetry and Laser Doppler Velocimetry. Two heating configurations are studied: symmetrical (same heat flux is imposed on both walls) and asymmetrical (only one wall is heated, the other one being adiabatic). For the study with symmetrical heating configuration, experimental data from Daverat's thesis are analysed by a zonal approach. The channel is split into several zones and a scaling analysis is conducted in order to explain experimental observations. Thus, the study focuses on heat transfer, pressure evolution in the channel and fluctuations, in particular, the evaluation of the maximum Reynolds stress. The asymmetrical configuration is studied for the transient regime and the steady regime. For the transient regime, early stage (first hours) is characterised in terms of wall temperature, velocity and two- or three-dimensional flow behaviour. A large-scale reversal flow is observed. The impact of external thermal stratification is also studied. For the steady regime, thermal and dynamic behaviours are studied and two different states are distinguished and characterised. Reversal flows are also observed. Finally, the influence of the Prandtl number and the channel width is discussed
Muller, Dorothée. "Optimisation des potentialités d’un transistor LDMOS pour l’intégration d’amplificateur de puissance RF sur silicium." Limoges, 2006. https://aurore.unilim.fr/theses/nxfile/default/8c93dadd-0847-4920-96c8-e1f79fc507d7/blobholder:0/2006LIMO0041.pdf.
Full textThe RF power amplifiers realized from components stemming from III-V technologies are at present the most successful because of their intrinsic physics properties. Nevertheless these technologies do not completely answer the requirements of the radiotelephony mobile market in term of cost of returns. New generations of MOS power transistors on silicon such as the LDMOS appeared to answer this need. These power devices have the advantage to be realized in mature technologies and offer very honourable performances to much lower costs, what is a major trump card in the current context where the cellular telephone market is very sensitive to the price of components. This thesis deals with a reflection on the potentialities of a transistor LDMOS integrated into a 0. 25 µm BiCMOS technology and on the optimization of its performances for RF power amplifiers circuits integrated on silicon. Firstly, the LDMOS transistor physical mechanisms and also the main reasons that make the LDMOS transistor a better candidate than the MOSFET for radio frequencies applications are presented. The work described afterward articulates around the realization and the optimisation of the LDMOS transistor for RF power applications. In fact, the technological parameters are determined in order to get a device, which output characteristics match the ones fixed by the application. Then an analysis is made to identify the device intrinsic and extrinsic parameters, which are susceptible to improve its dynamic performances. For it the effect of the modifications of architecture, layout as well as the manufacturing process on the dynamic characteristics were studied and ended in promising results. Indeed the performances of the optimized transistor LDMOS reach the state of the art
Zhao, Shengying. "Studying the nucleon structure via double deeply virtual compton scattering at the Jefferson Laboratory." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS147.
Full textGeneralized Parton Distributions (GPDs) have emerged over the 1990s as a powerful paradigm to study the structure and dynamics of the nucleon. Encoding the correlations between the elementary constituents of the nucleon (the partons), GPDs allows 3-dimensional imaging of the nucleon from the dynamical link between the transverse position and the longitudinal momentum of partons. The Double Deeply Virtual Compton Scattering (DDVCS) process consists of the scattering of a virtual photon off the nucleon, the virtual photon in the final state eventually generating a lepton pair, which can be either an electron-positron or a muon-antimuon pair. The virtualities of the initial space-like photon and the final time-like photon can be measured and varied independently, allowing one to map out the initial parton momentum dependency of GPDs independently of their transferred momentum dependency. This unique feature of DDVCS is of relevance, among others, for the determination of the transverse parton densities and the distribution of nuclear forces.This document presents a study of the DDVCS process in the context of the Continuous Electron Beam Accelerator Facility (CEBAF) at the Jefferson Laboratory (JLab, Newport News, VA, USA). The benefit of DDVCS for the extraction of GPDs is demonstrated from model-predicted pseudo-data. This involves phenomenological studies of the DDVCS process and the development of simulation tools, such as an event generator and a fitter algorithm, for the evaluation of the performances of a DDVCS experiment. The feasibility of possible experimental projects is discussed, including an ideal configuration and the large acceptance detector SoLID (Solenoidal Large Intensity Device). Considering polarized electron and positron beams, linear combinations of the Compton Form Factors (CFFs) are extracted from simulated experimental pseudo-data. GPDs are further deduced from CFFs using the fitter algorithm specifically developed
Barbusse, Danielle. "Contribution à la caractérisation des matériaux : étude des couches minces, multicouches et superréseaux III-V et II-VI par double diffraction des rayons X (composition, qualité, contraintes) : étude structurale par absorption X au seuil K d'une série de complexes du cobalt et du fer, XANES et EXAFS de laboratoire." Montpellier 2, 1991. http://www.theses.fr/1991MON20189.
Full textDa, Costa Hirata Silvia. "STABILITE DE LA CONVECTION THERMIQUE ET/OU SOLUTALE EN COUCHES FLUIDE ET POREUSE SUPERPOSEES." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2007. http://tel.archives-ouvertes.fr/tel-00175767.
Full textPszczola, Agnieszka, and Grzegorz Walachowski. "Testing for jumps in face of the financial crisis : Application of Barndorff-Nielsen - Shephard test and the Kou model." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2872.
Full textThe purpose of this study is to identify an impact on an option pricing within NASDAQ OMX Stockholm Market, if the underlying
asset prices include jumps. The current financial crisis, when jumps are much more evident than ever, makes this issue very actual and important in the global sense for the portfolio hedging and other risk management applications for example for the banking sector. Therefore, an investigation is based on OMXS30 Index and SEB A Bank. To detect jumps the Barndorff-Nielsen and Shephard non-parametric bipower variation test is used. First it is examined on simulations, to be finally implemented on the real data. An affirmation of a jumps occurrence requires to apply an appropriate model for the option pricing. For this purpose the Kou model, a double exponential jump-diffusion one, is proposed, as it incorporates essential stylized facts not available for another models. Th parameters in the model are estimated by a new approach - a combined cumulant matching with lambda taken from the Barrndorff-Nielsen and Shephard test. To evaluate how the Kou model manages on the option pricing, it is compared to the Black-Scholes model and to the real prices of European call options from the Stockholm Stock Exchange. The results show that the Kou model outperforms the latter.
Brazzolotto, Xavier. "Implication des protéines IRP (Iron Regulatory Protein) dans le métabolisme du fer chez les animaux." Phd thesis, Université Joseph Fourier (Grenoble), 2001. http://tel.archives-ouvertes.fr/tel-00193675.
Full textLa réactivité de la protéine recombinante IRP1 humaine, purifiée sous sa forme aconitase [4Fe-4S], a été étudiée vis à vis d'autres effecteurs que le fer capables de modifier l'activité des IRP. Ainsi des excès assez modestes de diverses espèces réactives de l'oxygène ne peuvent former que l'espèce [3Fe-4S] de la protéine. La doxorubicine, un composé cytostatique utilisé comme anti-cancéreux, a une action sur IRP1, mais elle dépend des conditions d'application et implique certainement des mécanismes multiples. In vitro, IRP1 est complètement activée pour la fixation d'ARN par un fort excès de 2-mercaptoéthanol. Parmi les diverses causes possibles de cet effet, les propriétés de solvant de ce produit (comme de l'éthanol) en sont responsables.
La recherche d'éventuels partenaires physiologiques de la protéine IRP1 a été entreprise par une étude double hybride chez la levure Saccharomyces cerevisiae, mais les constructions utilisées n'ont pas permis de déterminer de candidats potentiels. L'utilisation d'autres constructions ainsi que d'autres systèmes double hybride est envisagée pour la poursuite de cette étude.
Une nouvelle méthode de dosage de l'activité de fixation au motif IRE a été envisagée par l'utilisation d'un substrat fluorescent et de l'électrophorèse capillaire. Les résultats préliminaires obtenus n'ont pas encore abouti, mais ils contribuent à donner des orientations pour le développement de cette méthode présentant de nombreux avantages.
Des changements de conformation entre les deux formes actives de IRP1 ont été analysés par deux méthodes structurales en solution. La formation de certains éléments de structure secondaire d'IRP1 dépend de l'état d'activité de la protéine et ils sont sensibles à la fixation des substrats. Les propriétés hydrodynamiques d'IRP1 varient aussi lors de ces différents changements. Faute de structure à haute résolution, ces informations permettent toutefois de se représenter le comportement structural d'IRP1 dans son rôle de régulateur.
Bascoul, Guillaume Pierre. "Double-diffusive convection in stars." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613006.
Full textDegorce, Jean-Yves. "DYNAMIQUE HORS EQUILIBRE DE PHENOMENES DE TRANSPORT DANS UN SOLIDE ABSORBANT, SOUMIS A UNE IMPULSION LASER." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2005. http://tel.archives-ouvertes.fr/tel-00008479.
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