Дисертації з теми "Nonlinear dissipation"
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Harris, Shirley Elizabeth. "Nonlinear wave equations with dispersion, dissipation and amplification." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241561.
Повний текст джерелаLulla, Kunal. "Dissipation and nonlinear effects in nanomechanical resonators at low temperatures." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/12717/.
Повний текст джерелаVierheilig, Carmen [Verfasser]. "Interplay between dissipation and driving in nonlinear quantum systems / Carmen Vierheilig." Regensburg : Univ.-Verl. Regensburg, 2011. http://d-nb.info/1012150712/34.
Повний текст джерелаNazari, Farshid. "Strongly Stable and Accurate Numerical Integration Schemes for Nonlinear Systems in Atmospheric Models." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32128.
Повний текст джерелаSchmitt, James Tyler. "Damage initiation and post-damage response of composite laminates by multiaxial testing and nonlinear optimization." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/schmitt/SchmittJ1208.pdf.
Повний текст джерелаVerniero, J. L. "Turbulence in heliospheric plasmas: characterizing the energy cascade and mechanisms of dissipation." Diss., University of Iowa, 2019. https://ir.uiowa.edu/etd/6870.
Повний текст джерелаGandomzadeh, Ali. "Dynamic soil-structure interaction : effect of nonlinear soil behavior." Phd thesis, Université Paris-Est, 2011. http://tel.archives-ouvertes.fr/tel-00648179.
Повний текст джерелаBehlke, Rico. "Dissipation at the Earth's Quasi-Parallel Bow Shock." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6123.
Повний текст джерелаOtt, Richard J. "An Effective Damping Measure: Examples Using A Nonlinear Energy Sink." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1354032639.
Повний текст джерелаYang, Fan [Verfasser]. "Investigation of the Interaction, Nonlinear and Dissipation Effects in Nano-Membrane Resonators by Optical Interferometry / Fan Yang." Konstanz : KOPS Universität Konstanz, 2020. http://d-nb.info/1212796446/34.
Повний текст джерелаHashemi, Nastaran. "Exploring the Nonlinear Dynamics of Tapping Mode Atomic Force Microscopy with Capillary Layer Interactions." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/28112.
Повний текст джерелаPh. D.
Koneru, Saradhi. "A thermodynamic approach for compaction of asphaltic composites." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1147.
Повний текст джерелаMarshall, Justin D. "Development, Analysis and Testing of a Hybrid Passive Control Device for Seismic Protection of Framed Structures." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/30152.
Повний текст джерелаPh. D.
Michel, Guillaume. "Parois et ondes de surface : dissipation, effet Doppler et interactions non linéaires." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEE038/document.
Повний текст джерелаIn this thesis, we study the impact of solid boudaries on surface waves. We first consider the dissipation caused by dynamical wetting. We experimentally show how the damping of surface waves evolves with the size of the meniscus and demonstrate that in perfect wetting it leads to a nonlinear behavior as soon as the meniscus oscillation amplitude compares to the thickness of the boundary layer. Secondly, we investigate energy exchanges through scales occuring when a surface wave reflects on an oscillating wall, the so-called generalized Doppler effect. We evidence the creation of Doppler-shifted waves, compute their amplitudes and illustrate how the continuous bouncing of surface waves on wavemakers may lead to self-similar spectra competing with the ones of wave turbulence. Finally, we focus on nonlinear interaction between surface waves. We prove that gravity waves can undergo triad resonances in confined geometry. Going beyond the consequencies of solid boundaries, we perform experiments on four-wave interactions in the gravity regime and describe large scales in capillary wave turbulence
Phillips, Adam Richard. "Large-Scale Cyclic Testing and Development of Ring Shaped - Steel Plate Shear Walls for Improved Seismic Performance of Buildings." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73513.
Повний текст джерелаPh. D.
Lavarnway, Daniel L. "Evaluating the Use of Ductile Envelope Connectors for Improved Blast Protection of Buildings." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1365001432.
Повний текст джерелаSternberger, Antoine. "Atténuation vibratoire non-linéaire de structures modales creuses par ajout de matériaux granulaires." Thesis, Le Mans, 2018. http://www.theses.fr/2018LEMA1018/document.
Повний текст джерелаThe use of granular material in industrial structures to reduce vibration levels is an alternative toviscoelastic surfacing, which is highly dependent on temperature conditions. For the naval and aeronauticalindustry, the challenge is to improve reliability and comfort. The levels of interaction between the grainsdepend on the control parameters (acceleration level), but also on the characteristics of the constituentmaterials of the grains, the moisture content of the surrounding fluid, the geometry and dimensions of thegrains, as well as their containment conditions.For a given acceleration, independent of the point of structure, the relevance of the choice of a granularmaterial with respect to the same non-deformable mass is demonstrated by the study of the vibration of a rigidcavity mounted on an oscillator partially filled. The parametric variations of the types of confinement in thecavity as well as the constituent material of the grains make it possible to extract the influent parameters inthe energy dissipation. The development of an analytical model with localized constants allows to simulate theenergy dissipated by the system via a reduced number of coefficients representing the vibratory dynamics ofthe granular matter. The comparison of this model with experiments makes it possible to validate itseffectiveness and its predictive character in the dissipation of the vibratory energy of a dynamic system.For a modal structure, where the acceleration level is dependent on the point of the structure, theoptimization of the grain cluster positioning is shown
Luiz, Gustavo de Oliveira 1988. "Dynamics of coupled micro-oscillators = Dinâmica de micro-osciladores acoplados." [s.n.], 2017. http://repositorio.unicamp.br/jspui/handle/REPOSIP/325686.
Повний текст джерелаTese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
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Resumo: Nas últimas décadas a optomecânica de microcavidades chamou a atenção de cientistas e engenheiros, que encontraram na interação entre luz e ondas acústicas aplicações que variam de sensores de massa com resolução atômica, até a preparação de estados quânticos de osciladores harmônicos mesoscópicos, passando por simuladores quânticos, filtros ópticos controláveis opticamente, criação de estados topológicos para luz e fônons, apenas citando alguns exemplos. Apesar das diversas demonstrações de vários dispositivos, sendo discos e cristais fotônicos os formatos mais comuns, há ainda um grande esforço no sentido de aperfeiçoá-los reduzindo perdas ópticas e mecânicas e suprimindo outros fenômenos de óptica não-linear, como absorção de dois fótons, que podem impedir seu funcionamento apropriado. Como ressonadores ópticos e mecânicos tipicamente compartilham a mesma estrutura nestes dispositivos, seus projetos são acoplados, dificultando o aprimoramento independente de cada um. Nesta tese usamos dispositivos optomecânicos de campo próximo, cuja interação entre modos mecânicos e ópticos se dá através do campo evanescente do último, para desacoplar o projeto mecânico do óptico, o que nos permitiu estudar a otimização do ressonador mecânico sem qualquer efeito sobre a cavidade óptica. Com um ressonador mecânico de silício composto por dois osciladores acoplados, pudemos demonstrar que o correto equilíbrio das massas de cada oscilador é um método simples e eficiente para suprimir as perdas devido à radiação de energia mecânica para o substrato na escala de frequência de 50 MHz. Este processo permitiu que fatores de qualidade limitados por perdas relacionadas ao material e à superfície, da ordem de 10 mil à temperatura ambiente e de 50 mil a aproximadamente 25 K, fossem obtidos. Também observamos nestes dispositivos o fenômeno de auto-pulsação, que apresenta uma dinâmica própria tão interessante quanto a optomecânica, apesar de impedir a operação apropriada dos osciladores optomecânicos. Estudamos este fenômeno separadamente e demonstramos que estes pulsos, ocorrendo em duas cavidades ópticas acopladas por seus campos evanescentes, podem sincronizar com o campo óptico sendo o único intermediador. Ambas as demonstrações têm implicações importantes, abrindo caminho para o desenvolvimento de novas plataformas de interesse tanto científico quanto tecnológico, como estruturas para o estudo de estados topológicos para a luz e para ondas acústicas e geradores de sinal de radio-frequência de alto desempenho. Além disso, os dispositivos foram todos produzidos em uma fábrica comercial, o que também demonstra que sua fabricação está pronta para ser escalada para produção em massa
Abstract: Cavity optomechanics in the micro-scale has attracted the attention of scientists and engineers on the last few decades, who encountered applications to the interaction of light and acoustic waves ranging from atomic resolution mass sensors to the preparation of quantum states of mesoscopic harmonic oscillators, passing by quantum simulators, optically controllable optical filters, formation of topological states for both photons and phonons, just to mention a few examples. Although various devices have been demonstrated, with disks and photonics crystals being the most common designs, there is still a large effort to improve them by reducing optical and mechanical losses and suppressing other non-linear phenomena, such as two-photon absorption, that may affect their proper operation. Because optical and mechanical resonators typically share the same structure in these devices, their designs are coupled, which complicates the independent improvement of each one. In this thesis we used near-field optomechanical devices, whose mechanical modes interact with the optical through the latter¿s evanescent field, to decouple the mechanical design from the optical, what allowed us to focus all attention on the mechanical resonator. With a silicon mechanical resonator composed of two coupled oscillators, we could demonstrate that the correct balance of the masses of the oscillators is an efficient and simple way to suppress losses due to energy radiation to the substrate at the 50 MHz frequency range. This strategy led to material and surface limited quality factors close to 10k at room temperature and 50k at approximately 25 K. We also observed the phenomenon of self-pulsing in these devices, which presents dynamics as interesting as the optomechanical interactions do, in spite of being a problem for the proper operation of the optomechanical devices. We studied this phenomenon separately and demonstrated that these pulses, when occurring in two evanescently coupled optical cavities, may synchronize with the optical field being the sole intermediary. These two demonstrations have important implications, paving the way for new platforms of scientific and technological interest, such as structures for the study of topological states for both light and acoustic weaves as well as high efficiency radio-frequency signal generators. Moreover, these devices were all fabricated in a commercial foundry, which also demonstrates that the fabrication of such technology is ready to be scaled up to mass production
Doutorado
Física
Doutor em Ciências
153044/2013-6
CNPQ
Aguirre, Herrera Santiago Alberto, and Barazorda Elio Andre Vidal. "Comportamiento estructural de una edificación esencial de mediana altura usando aisladores de base y disipadores SLB." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/654612.
Повний текст джерелаThis article consists of analyzing a new high-tech anti-seismic control alternative for the construction of hospitals in Peru, which in its regulations requires the use of base insulation for essential buildings. For this, the structural evaluation of a building constructed with seismic isolators is chosen and the same with the implementation of the SLB (Shear Link Bozzo) energy dissipation system. The results analyzed for each anti-seismic control technique studied are: mezzanine drifts, floor accelerations, energy balance and analysis of plastic hinges, based on the philosophy of continuous functionality.
Trabajo de investigación
Yousefzadeh, Behrooz. "Wave transmission in finite dissipative nonlinear periodic structures." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60166.
Повний текст джерелаApplied Science, Faculty of
Graduate
Sendanayake, Sukhi Vanessa. "Seismic mitigation of steel modular buildings using novel inter-modular connections." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/180893/1/Sukhi%20Vanessa_Sendanayake_Thesis.pdf.
Повний текст джерелаRolt, Kenneth D. "A dissipative wave packet approach for unified nonlinear acoustics." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28080.
Повний текст джерелаMertens, Christopher J. "Many-body theory of dissipative quantum optical systems." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/30316.
Повний текст джерелаKozyreff, Gregory. "Nonlinear aspects of the dynamics induced by dissipative light-matter interaction." Doctoral thesis, Universite Libre de Bruxelles, 2001. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211644.
Повний текст джерелаMotivé par de récentes expériences menées sur des lasers miniatures avec absorbant saturable, nous en avons repris la description théorique. Les nouvelles valeurs de paramètres suggérées par l'expérience nous ont amenés à découvrir de nouveaux comportements dynamiques pour ces systèmes. En particulier, nous avons décrit comment l'intensité délivrée par ces lasers devenait temporellement sinusoïdale, puis impulsionnelle sur un très petit intervalle de paramètres.
Par la connaissance acquise du laser à absorbant saturable, nous avons pu comprendre comment s'établissait un régime impulsionnel semblable dans un autre laser. Il s'agissait du laser multimode à pompage longitudinalement inhomogène. Il est apparu en effet qu'une partie du milieu emprisonné dans la cavité optique agissait à la manière d'un absorbant saturable, déstabilisant ainsi l'émission continue de ce laser. Nous avons également montré que, dans certaines circonstances, son état dynamique présentait des effets de mémoire. Une autre propriété importante de la dynamique du laser multimode a été mise en évidence: pour de petites perturbations, l'intensité totale présente un comportement plus régulier que les intensités modales prises séparément.
Ce type intrigant d'auto organisation fut rencontré plus tard, lorsque nous avons envisagé la dynamique d'un réseau de lasers à semi conducteur couplés par un feedback optique. Le retard accumulé par la lumière au cours de ce feedback est un paramètre essentiel du problème. Ce système important sur le plan technologique s'est révélé extrêmement riche sur le plan dynamique. Nous avons pu montrer que plus le retard était grand, plus les lasers avaient tendance à se synchroniser. Cela fut observé aussi bien en régime continu qu'en régime périodique ou chaotique. Par une telle synchronisation, la qualité du rayon optique émis par le réseau de lasers augmente spectaculairement, élargissant par là ses possibilités d'application.
Au début des années 1990, les physiciens commencèrent à étudier systématiquement les effets d'interférence quantique dans l'interaction lumière matière. Ceci faisait suite à l'annonce fracassante que de tels effets devaient permettre de construire des lasers sans inversion de population. Récemment, une série d'expériences a montré que de telles interférences quantiques étaient à l’œuvre dans le laser miniature LNP. Une partie de cette thèse y fut consacrée. Nous avons montré que le comportement dynamique observé résultait d'un renforcement quantique de l'absorption stimulée par les niveaux énergétiques inférieurs.
Nous avons poursuivi notre étude des effets d'interférence quantique sur un schéma électronucléaire. Nous avons montré que pour ce système, un rayon gamma peut être amplifié sans inversion de population. Ce résultat est très important, compte tenu du fait qu'une telle inversion est techniquement impossible à réaliser pour ces très hautes fréquences électromagnétiques, empêchant jusqu'ici la réalisation de lasers gamma. Afin d'atteindre l'amplification sans inversion, un rayonnement d'appoint dans le domaine optique s'avère nécessaire. Tenant compte de la décroissance de ce champ optique en cours de propagation, et donc de la diminution des effets quantiques associés, nous avons déterminé une distance optimale de propagation. Au-delà de cette distance, l'amplification se mue en absorption. Une telle information est dès lors cruciale sur le plan expérimental.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Feng, Bao-Feng. "Numerical Studies on Nonlinear Dispersive Waves in Unstable and Dissipative Systems." Kyoto University, 2000. http://hdl.handle.net/2433/180968.
Повний текст джерелаTokuda, Hidekazu. "Dynamics of nonlinear dissipative traveling waves under feedback and external forcing." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136751.
Повний текст джерелаGustave, François. "Dynamique de phase et solitons dissipatifs dans des lasers à semiconducteurs." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4003/document.
Повний текст джерелаDissipative solitons (DS) are self-localized wave-packets appearing in spatially extended dissipative systems. In optics, all the DS that have been observed in propagative systems can be cast in two categories, depending on the presence or absence of an external forcing, i.e. the phase symmetry is broken or not. In forced systems, DS are locked in phase to forcing whereas without forcing, their phase is free an can wander in the course of time. In this thesis, we study the formation of propagative DS in two different experimental systems that fundamentally differ from the presence or lack of an external forcing. The first one is a Vertical Cavity Surface Emitting Laser (VCSEL) submitted to a frequency selective feedback, in which DS form in the transverse plane of the system (2D). We analyze how the synchronization of the longitudinal frequencies (mode-locking) can give rise to tri-dimensionnal localization of light: light bullets. The second system is a highly multimode semiconductor ring laser with external forcing, whose spatial extension takes place along the propagation dimension. When the forcing frequency is slightly detuned from the natural frequency of the system, we can see the appearance of self-confined 2 pi phase rotations embedded in a homogeneous (synchronized) state. We then report on the first observation of DS that form in the phase of the optical wave : dissipative phase solitons
Chudoung, Jerawan. "Robust Control for Hybrid, Nonlinear Systems." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/26983.
Повний текст джерелаPh. D.
Sakurai, Atsunori. "Exploring Nonlinear Responses of Quantum Dissipative Systems from Reduced Hierarchy Equations of Motion Approach." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/179368.
Повний текст джерелаThomas, Roland. "L'instabilité modulationnelle en présence de vent et d'un courant cisaillé uniforme." Phd thesis, Aix-Marseille Université, 2012. http://tel.archives-ouvertes.fr/tel-00716089.
Повний текст джерелаJeambrun, Denis. "Propagation d'une onde de cisaillement en milieu non linéaire dissipatif." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 1995. http://tel.archives-ouvertes.fr/tel-00755781.
Повний текст джерелаPesch, Matthias. "Formation and properties of a discrete family of dissipative solutions in a nonlinear optical system." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983669546.
Повний текст джерелаGütlich, Björn. "Control of nonlinear optical structures from the guiding of dissipative solitons to spatio-temporal synchronisation." Göttingen Cuvillier, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016214833&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Повний текст джерелаMacias, Diaz Jorge. "A Numerical Method for Computing Radially Symmetric Solutions of a Dissipative Nonlinear Modified Klein-Gordon Equation." ScholarWorks@UNO, 2004. http://scholarworks.uno.edu/td/167.
Повний текст джерелаSemaan, Georges. "Soliton dynamics in fiber lasers : from dissipative soliton to dissipative soliton resonance." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0029/document.
Повний текст джерелаIn this thesis, we investigate experimentally the generation of high energy nanosecond tunable square pulses and high output power ultrashort pulses in fiber lasers. First, since pulse dynamics are dominated by the interaction of the fiber's cubic Kerr nonlinearity and chromatic dispersion with an intensity-discriminating mechanism referred to as a saturable absorber, the stability of a harmonic mode-locked distribution is studied by external injection of a continuous wave. Finally, we implemented nanomaterial based saturable absorbers in fiber laser configuration to generate ultrashort pulses with high average output power. Different techniques of achieving such components are explicitly detailed: ultrashort pulse generation in ring cavities where graphene and topological insulators are deposited on optical tapers to form a saturable absorber
Djaferi, Berat. "Insertion of Dissipative Devices in Precast RC Structures." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9066/.
Повний текст джерелаMancas, Ciprian. "DISSIPATIVE SOLITONS IN THE CUBIC–QUINTIC COMPLEX GINZBURG–LANDAU EQUATION:BIFURCATIONS AND SPATIOTEMPORAL STRUCTURE." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2912.
Повний текст джерелаPh.D.
Department of Mathematics
Sciences
Mathematics PhD
Beenken, Wichard Johann Daniel. "Theory of nonlinear polarization spectroscopy in the frequency domain (NLPF) with applications to photosynthetic antennae." Doctoral thesis, [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970522789.
Повний текст джерелаBesse, Valentin. "Dynamique spatiale de la lumière et saturation de l’effet Kerr." Thesis, Angers, 2014. http://www.theses.fr/2014ANGE0030/document.
Повний текст джерелаWe present a study of light dynamics and measurements of the nonlinear optical characteristics of carbon disulphide. In the first part, we calculate using the classical model, the nonlinear susceptibilities up to the fifth order taking into account local field corrections. We express different assumptions that we confirm or refute by measuring the nonlinear absorption coefficient and the nonlinear refractive index. The measurements are performed by means of two nonlinear characterization methods combined with an imaging 4f system. We analyse the experimental data using a newly developed method which numerically inverts the analytical solutions of the differential equations which describe the evolution of the beam, using Newton’s method. In the second part, we observe light filamentation at wavelength 532 nm, in the picoseconds regime. Then we measure the effective third order nonlinear refractive index n2,eff versus the incident intensity. By fitting the curve of the Kerr effect saturation, we develop a new model. Numerically solving this model, allows us to reproducethe experimentally observed filamentation. The last part is dedicated to the study of dissipative solitons dynamics. The complex Ginzburg-Landau equation with cubic-quintic nonlineraties is numerically solved in various configurations : soliton fundamental dipole, quadrupole, vortex and square rhombic
Rimoldi, Cristina. "Événements extrêmes dans des cavités optiques non linéaires étendues." Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4095/document.
Повний текст джерелаExtreme events are phenomena, often considered as catastrophic, that occur in the tail of a distribution usually deviating from an expected, exponential decay. In optics, these events were first studied in the context of fibers, where they have been extensively analyzed, as optical rogue waves, in light of the well known analogy between optics and hydrodynamics, through the nonlinear Schroedinger equation. With the development and the broadening of the field, extreme events have been also studied in dissipative optical systems with or without spatial degrees of freedom. In this Thesis we focused on the study of extreme events in three different active and dissipative optical systems, each presenting one or two spatial degrees of freedom, either in the transverse plane, perpendicular to the direction of propagation of light, or in the propagation direction. Localized structures of different nature represent an important possible solution in each one of the systems here studied, hence their interaction and the role played in the formation of extreme events have been also investigated into details. In the first system, a monolithic broad-area semiconductor laser (VCSEL) with an intracavity saturable absorber, we report on the occurrence of extreme events in the 2D transverse plane of the electric field intensity. In particular we highlight the connection between these objects and cavity solitons, both stationary and oscillatory, also present in the system. In the second system, a highly multimode laser with optical injection spatially extended along the propagation direction, we analyze the interaction and merging of phase solitons, localized structures propagating along the cavity carrying a 2π phase rotation. Extreme events have been investigated in two configurations: a first one where they emerge from the collision of phase solitons with other transient structures carrying a negative chiral charge, and a second one where high-peak events emerge from an unstable roll regime where phase solitons are not a stable solution. In both these systems we investigate the role of chirality in the extreme event formation. In the third system, a broad-area semiconductor laser (VCSEL) with optical injection, we study into details the interaction of cavity solitons in the transverse plane, described as two particles subjected to an interaction potential exponentially decreasing with the distance between the two objects: a possible analogy with hydrophobic materials is here suggested. Some preliminary results showing spatiotemporal extreme events in this system are also given
Lapre, Coraline. "Caractérisation des régimes de stabilité et instabilité des lasers à soliton dissipatif avec dynamiques soliton-similariton et régénération Mamyshev." Thesis, Bourgogne Franche-Comté, 2021. http://www.theses.fr/2021UBFCD053.
Повний текст джерелаModelocked ultrafast lasers producing picosecond and sub-picosecond pulses are well known to exhibit a very rich landscape of nonlinear dynamics that are of tremendous interest from both fundamental and applied perspectives. Although such instabilities from ultrafast laser have been studied for many decades, the recent development of advanced photonic measurement techniques has opened up new perspectives into their analysis. In this thesis, we report a detailed experimental study of the complex dynamical regimes of two different optical fibre laser systems operating around 1550 nm: a soliton-similariton laser, and a Mamyshev oscillator. In both cases, we use the time-frequency technique of frequency resolved optical gating for complete intensity and chirp characterisation in stable regimes of operation, and the real-time dispersive Fourier transform method to characterize shot-to-shot spectral fluctuations. For the particular case of the soliton-similariton laser, stable operation yields from 7 to 10 ps pulses of 30~nm spectral width and 0,32 mW average output power at 9,5 MHz. Instabilities seen in the soliton-similariton laser include novel startup, the generation of coupled soliton molecules, the emergence of complex intermittence and chaos, and the appearance of multipulse states. For the case of the Mamyshev oscillator, stable operation yields from 3 to 5 ps pulses of 90 à 100 nm spectral width and ~4 mW average output power at 6,37 MHz. We also present results on the characterization of the Noise-Like Pulse regime of the soliton-similariton laser with the addition of highly nonlinear fiber in the cavity, which generates broadband output spanning 1000 nm. As well as presenting a range of experimental results, numerical simulations are used to gain insight into the operation of the laser systems studied
Friedrich, Benjamin M. "Nonlinear dynamics and fluctuations in biological systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-234307.
Повний текст джерелаDas Thema der vorliegenden Habilitationsschrift in Theoretischer Biologischer Physik ist die nichtlineare Dynamik funktionaler biologischer Systeme und deren Robustheit gegenüber Fluktuationen und äußeren Störungen. Wir entwickeln hierzu theoretische Beschreibungen für zwei grundlegende biologische Prozesse: (i) die zell-autonome Kontrolle aktiver Bewegung, sowie (ii) selbstorganisierte Musterbildung in Zellen und Organismen. In Kapitel 2, untersuchen wir Bewegungskontrolle auf zellulärer Ebene am Modelsystem von Zilien und Geißeln. Spontane Biegewellen dieser dünnen Zellfortsätze ermöglichen es eukaryotischen Zellen, in einer Flüssigkeit zu schwimmen. Wir beschreiben einen neuen physikalischen Mechanismus für die Synchronisation zweier schlagender Geißeln, unabhängig von direkten hydrodynamischen Wechselwirkungen. Der Vergleich mit experimentellen Daten, zur Verfügung gestellt von unseren experimentellen Kooperationspartnern im Labor von J. Howard (Yale, New Haven), bestätigt diesen neuen Mechanismus im Modellorganismus der einzelligen Grünalge Chlamydomonas. Der Gegenspieler dieser Synchronisation durch mechanische Kopplung sind Fluktuationen. Wir bestimmen erstmals Nichtgleichgewichts-Fluktuationen des Geißel-Schlags direkt, wofür wir eine neue Analyse-Methode der Grenzzykel-Rekonstruktion entwickeln. Die von uns gemessenen Fluktuationen entstehen mutmaßlich durch die stochastische Dynamik molekularen Motoren im Innern der Geißeln, welche auch den Geißelschlag antreiben. Um die statistische Physik dieser Nichtgleichgewichts-Fluktuationen zu verstehen, entwickeln wir eine analytische Theorie der Fluktuationen in einem minimalen Modell kollektiver Motor-Dynamik. Zusätzlich zur Regulation des Geißelschlags durch mechanische Kräfte untersuchen wir dessen Regulation durch chemische Signale am Modell der Chemotaxis von Spermien-Zellen. Dabei charakterisieren wir einen grundlegenden Mechanismus für die Navigation in externen Konzentrationsgradienten. Dieser Mechanismus beruht auf dem aktiven Schwimmen entlang von Spiralbahnen, wodurch ein räumlicher Konzentrationsgradient in der Phase eines oszillierenden chemischen Signals kodiert wird. Dieser Chemotaxis-Mechanismus unterscheidet sich grundlegend vom bekannten Chemotaxis-Mechanismus von Bakterien. Wir entwickeln eine Theorie der senso-motorischen Steuerung des Geißelschlags während der Spermien-Chemotaxis. Vorhersagen dieser Theorie werden durch Experimente der Gruppe von U.B. Kaupp (CAESAR, Bonn) quantitativ bestätigt. In Kapitel 3, untersuchen wir selbstorganisierte Strukturbildung in zwei ausgewählten biologischen Systemen. Auf zellulärer Ebene schlagen wir einen einfachen physikalischen Mechanismus vor für die spontane Selbstorganisation von periodischen Zellskelett-Strukturen, wie sie sich z.B. in den Myofibrillen gestreifter Muskelzellen finden. Dieser Mechanismus zeigt exemplarisch auf, wie allein durch lokale Wechselwirkungen räumliche Ordnung auf größeren Längenskalen in einem Nichtgleichgewichtssystem entstehen kann. Auf der Ebene des Organismus stellen wir eine Erweiterung der Turingschen Theorie für selbstorganisierte Musterbildung vor. Wir beschreiben eine neue Klasse von Musterbildungssystemen, welche selbst-organisierte Muster erzeugt, die mit der Systemgröße skalieren. Dieser neue Mechanismus erfordert weder eine vorgegebene Kompartimentalisierung des Systems noch spezielle Randbedingungen. Insbesondere kann dieser Mechanismus proportionale Muster wiederherstellen, wenn Teile des Systems amputiert werden. Wir bestimmen analytisch die Hierarchie aller stationären Muster und analysieren deren Stabilität und Einzugsgebiete. Damit können wir zeigen, dass dieser Skalierungs-Mechanismus strukturell robust ist bezüglich Variationen von Parametern und sogar funktionalen Beziehungen zwischen dynamischen Variablen. Zusammen mit Kollaborationspartnern im Labor von J. Rink (MPI CBG, Dresden) diskutieren wir Anwendungen auf das Wachstum von Plattwürmern und deren Regeneration in Amputations-Experimenten
Golzan, Seyyed Behnam. "Simplified design method for energy dissipating devices in retrofitting of seismically isolated bridges." Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8948.
Повний текст джерелаRésumé: Les ponts routiers ont une grande valeur dans un pays parce qu’en cas de catastrophe naturelle, ils peuvent servir comme des lignes pour sauver des vies. Étant vulnérable sous des charges sismiques importantes, on peut considérer différentes méthodes pour concevoir des ponts routiers résistants et également pour réhabiliter des ponts existants. Dans cette étude, l'isolation de la base a été considérée comme une méthode efficace qui peut réduire significativement les effets des charges sismiques sur la structure. En réduisant la demande en ductilité sur la structure sans une augmentation notable de force, la structure est conçue pour rester élastique sous des charges sismiques. Le problème associé aux ponts isolés, particulièrement avec des appuis en élastomère, peut être leurs déplacements excessifs sous les charges de service et de séisme. Ceci peut défier l’objectif d'utiliser des appuis en élastomère pour les ponts typiques de petite portée où les joints de dilatation et les dégagements peuvent aboutir à une augmentation significative des frais d'exploitation et de maintenance. Ainsi, supplémenter la structure avec des amortisseurs d’une certaine rigidité peut servir de solution, ce qui peut cependant augmenter l’effort tranchant transmis à la sous-structure. Cette étude a pour but de fournir une méthode simplifiée afin d’évaluer les paramètres optimaux des amortisseurs dans les ponts isolés. Dans cette thèse, premièrement, basé sur une étude paramétrique, quelques directions sont données pour l'utilisation de dispositifs d'isolation simples, dont les appuis en élastomère, afin de réhabiliter des ponts existant avec une haute importance. Les paramètres comme la géométrie du pont, les clauses des normes et le type de sol sur lequel la structure est construite ont été appliqués sur un pont typique de deux portées. Il est conclu que les paramètres mentionnés peuvent déterminer l'emploi d'isolement de la base des ponts routiers. À la deuxième phase, basé sur le coefficient de réponse élastique des ponts isolés, une méthode de conception simplifiée d’amortisseur pour des ponts routiers réguliers isolés à la base a été présentée dans cette étude. En sélectionnant des objectifs pour la réduction du déplacement et la variation de l’effort tranchant, la rigidité et l'amortissement exigés d'un amortisseur hystérétique peuvent être déterminés. L’étude s’est poursuivie par une modélisation numérique d’un pont à deux portées pour vérifier l'efficacité de la méthode. Pour un modèle numérique d'un pont isolé typique, la méthode a été utilisée pour identifier des paramètres linéaires équivalents pour un certain déplacement et effort tranchant désigné. Par la suite, assumant un amortisseur de type hystérétique, les paramètres non linéaires de l’amortisseur ont été calculés et utilisés. La comparaison des résultats du modèle numérique sans amortisseur et avec l'amortisseur a démontré que la méthode proposée est suffisamment précise. Par la suite, un nouvel amortisseur hystérétique simple en acier a été conçu. Cinq spécimens ont été fabriqués de deux différents grades d’acier et ont été testés en combinaison avec un isolateur à l’échelle réelle dans le laboratoire de structures de l'Université de Sherbrooke. La procédure comprenait la caractérisation des spécimens par des tests cycliques en contrôle de déplacement et par la suite la réalisation d’essais par la méthode de sous-structuration dynamique en temps réel. Les résultats des essais ont été utilisés pour établir un modèle numérique du système qui a subi des analyses temporelles non linéaires sous plusieurs séismes. Le résultat des essais expérimentaux et numériques montrent une conformité acceptable avec la méthode simplifiée.
Ben, braham Fatma. "Contribution à l’étude théorique et expérimentale d’un oscillateur laser fonctionnant en régime impulsionnel dans les bandes spectrales C et L." Thesis, Angers, 2018. http://www.theses.fr/2018ANGE0025.
Повний текст джерелаThis work deals with the development of a fiber laser generating high energy and width tunable square pulses and high-energy giant pulses. First, we have developed a numerical model to study the generation of rectangular pulses in a double amplifier fiber laser. The objective is to study the impact of the non-linear effect induced by the microstructured optical fiber on the control of the square pulse duration. A set of laser parameters allowed us to generate high energy square pulses in the dissipative soliton resonance (DSR) regime. In addition, several experiments have been set up to optimize the generation of the DSR pulse in terms of energy and duration. Experimentally, high energy giant pulses from a passively mode-locked fiber ring laser coupled to a long external cavity are obtained. This allowed us to generate a wide range of pulse duration of μs at a low repetition rate in cavities using artificial saturable absorbers
Bonis, Ioannis. "Optimisation and control methodologies for large-scale and multi-scale systems." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/optimisation-and-control-methodologies-for-largescale-and-multiscale-systems(6c4a4f13-ebae-4d9d-95b7-cca754968d47).html.
Повний текст джерелаChouli, Souad. "Structures optiques dissipatives en cavité laser à fibre." Phd thesis, Université de Bourgogne, 2011. http://tel.archives-ouvertes.fr/tel-00692049.
Повний текст джерелаChou, Chi-Feng, and 鄒季峯. "Stick Model Nonlinear History Analysis and Damper Dissipation Evaluation." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/88893712935074527833.
Повний текст джерела國立交通大學
土木工程系所
104
Today, elastic structural analysis is conducted for the design of structures without and with dampers in the industry. When earthquakes are small, analysis results may be acceptable. However, when earthquakes are severe enough, structures may exceed elastic limits. Analysis results may not be the same as expected and the design may not be conservative enough. Therefore, nonlinear behavior of structures without and with velocity- and displacement dampers is investigated through time-history analysis in this thesis. Capacity curve is obtained from nonlinear pushover analysis by using ETABS and nonlinear spring for each story is established from the relationship of story shear and inter-story displacement. In the nonlinear pushover analysis, default plastic hinges built in ETABS are adopted. The feasibility of the default plastic hinges is verified by the experimental results provided by the National Center for Research on Earthquake Engineering. Since it is very time-consuming to perform 3D nonlinear structural time-history analysis, the nonlinear structure is simplified to stick model. From the case analysis of a high-rise building, if the structure is assumed to be elastic, displacements are underestimated but absolute accelerations and base shear are overestimated compared with those obtained from nonlinear structural analysis. When velocity- or displacement-dependent dampers are added to the structure, elastic analysis overestimates the effect of dampers because energy dissipated by the structure is ignored. Moreover, the lateral displacement and lateral force demands of the dampers are underestimated. The effectiveness of the dampers cannot be as developed as expected. Therefore, nonlinear analysis is necessary for structures under earthquake loads.
Yi-TengChang and 張益騰. "Evaluation of Soil Liquefaction Potential by Using Artificial Neural Network and Nonlinear Energy Dissipation Principle." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/48801658667734863916.
Повний текст джерела國立成功大學
土木工程學系碩博士班
98
The soil liquefaction is always the important topics in the discipline of Geotechnical Engineering. Many methods related to evaluation of the potential of the soil liquefaction have been developed. However, the Simplified Empirical method the one that is much more common used both in academic and in practice. Since Nemat-Nasser and Shokooh in 1979 proposed the principle of relations between dissipation of seismic energy and the increment of pore water pressure during earthquake, the method on the basis of the seismic energy concept has become the mainstream on evaluation of the soil liquefaction potential. By referring the principle of the nonlinear energy dissipation that proposed by Berrill and Davis in 1985 and the liquefaction energy that calculated from the hysteresis loop obtained from the soil cyclic triaxial tests in laboratory, the neural network model is used in this study to simulate the liquefaction energy in field. The framework of the model is found by the auto trial and error process. And by associating with the statistical discriminant method, the critical line judging the occurrence of the soil liquefaction can be developed. With the 91% of success rate of the liquefaction assessment, the proposed neural network model is fair reasonable and suitable for the practice in geotechnical engineering.
Chang, Wonkeun. "Dissipative solitons and their applications." Phd thesis, 2009. http://hdl.handle.net/1885/149593.
Повний текст джерелаToundykov, Daniel. "Long-term dynamics of a semilinear wave equation with localized nonlinear dissipation, critical source term, and mixed boundary conditions /." 2007. http://wwwlib.umi.com/dissertations/fullcit/3260672.
Повний текст джерела