Дисертації з теми "Coupled excitation"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Coupled excitation".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Young, Anita. "Fluorescence studies in the inductively coupled plasma." Thesis, University of Plymouth, 2002. http://hdl.handle.net/10026.1/1686.
Повний текст джерелаCaughlin, Brenda Lea. "Analyte excitation and ionization in the argon inductively coupled plasma." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27038.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Kubota, Madoka. "Energy Harvesting Characteristics of Nonlinear Oscillators under Excitation." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199315.
Повний текст джерелаLebrun, Romain. "Coupled vortex dynamics in spin-torque oscillators : from resonant excitation to mutual synchronization." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS233/document.
Повний текст джерелаThe discovery of the giant magnetoresistance in 1988 is considered as the birth date of a new and dynamic research field called spintronics. The rich physics associated with spin transport has created a breakthrough for the future of nano-electronics. In the magnetism roadmap, spin-torque oscillators (STOs) are candidates for future generation of spintronic based rf-devices.At the beginning of this thesis, one major issue of spin-torque oscillators remained their poor spectral coherence. To overcome this issue, we have investigated different approaches: (i) the development of magnetic materials with a low damping and large spin-polarization, (ii) the study of collective mode dynamics in hybridized magnetic systems (iii) the stabilization of the STO dynamics with a reference external signal (iv) the synchronization of multiple STOs to enhance both their power and spectral coherence. We focus our work on vortex based STOs which present higher spectral coherences than other kinds of STOs.In a first part, we study the different mechanisms that can drive and stabilize the dynamics of a vortex based STO in the autonomous and non-autonomous regimes. We first highlight that the excitation of collective modes allows the harnessing the rf-properties of a single and isolated in a double vortex based STO. Then we report the ``perfect'' phase-locking of a STO with an external rf-current. To go beyond this analysis, we notice that a 1 Hz minimum linewidth and a flat phase noise level of -90 dBc/Hz at 1 kHz from the offset frequency in the locked state could be associated with the absence of phase slips, i.e desynchronization events. We demonstrate that the locking process is driven by a Field-like in-plane torque which gives the possibility to control with precision the STO locking process. In our double vortex based STO, we can even observe exotic behaviors such as multi-mode synchronization, self-resonance and eventually incoherent motion. Such a degree of control, unexpected for a nano-scale oscillator, is particularly promising for the development of STO based nanodevices.In a second part, we propose different concepts of spintronic rf-devices based on vortex STOs. We describe the basis of an on-chip STO based phase locked loop. By taking advantage of the large Field-like torque in our STOs, we develop a new radio-frequency detection scheme, more efficient than the state of the art Schottky diode, based on magnetization switching through the resonant and reversible expulsion of the vortex core. Finally, we show the first experimental observation of the electrical synchronization of two STOs connected directly in parallel or in series, or with an electrical delay line. In the synchronized state, we show a strong improvement of both the spectral coherence (by a factor 2) and the output power (by a factor 4, up to 1.6 μW). We also demonstrate, with an electrical delay line, the strong impact of the phase shift between the two STOs on the synchronized regime. These promising results open the way for the synchronization of STO arrays at zero field and without electrical delays.Ten years after their discovery, spin-torque oscillators have thus not yet revealed all their potential and promising applications could be soon targeted, in order to realize a spin logic circuit, bio-inspired spintronic devices and more classical rf-applications
Tzanidis, Ioannis. "Ultrawideband Low-Profile Arrays of Tightly Coupled Antenna Elements: Excitation, Termination and Feeding Methods." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1316439948.
Повний текст джерелаGarrido, Mauricio. "Quantum Optics in Coupled Quantum Dots." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1273589966.
Повний текст джерелаPatil, Anjali Narendra. "Delamination Detection in Concrete Using Disposable Impactors for Excitation." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3885.
Повний текст джерела陳志遠 and Chee-yuen George Chan. "Investigation of matrix effects on excitation conditions of dry inductively coupled plasma using laser ablation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42128687.
Повний текст джерелаChan, Chee-yuen George. "Investigation of matrix effects on excitation conditions of dry inductively coupled plasma using laser ablation." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42128687.
Повний текст джерелаSmith, Thomas Riddell. "Excitation processes within an inductively coupled plasma as a function of pressure and related studies." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184582.
Повний текст джерелаReeves, Kevin. "Dynamic-systems analysis of self-excitation associated with a capacitor-coupled substation (CCS) - induction machine system." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/5116.
Повний текст джерелаThe purpose of this thesis is therefore to establish the cause of SSR at the Meru-Petronet system, and other similar systems, and investigate various compensation techniques.
Hubert, Mickaël. "Relativistic coupled cluster theory for excited states at a general excitation rank : applications to diatomic molecules." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/2046/.
Повний текст джерелаThis thesis focuses on methodological developments of the theoretical evaluation of the quantum and relativistic energy of electronically excited states of an atom or a molecule. The wave-function method Coupled Cluster (CC) is currently one of the most accurate methods to calculate these states for many-body systems. The implementation presented is based on the many-body relativistic 4-component Dirac-Coulomb Hamiltonian and a Coupled Cluster wave function at arbitrary excitation rank. The excited states are evaluated using linear response theory by diagonalizing the Coupled Cluster Jacobian matrix. The work focuses on the evaluation of these second-quantized elements using a new commutator-based algorithm, and on its adaptation to a Dirac 4-component relativistic formalism. Finally, I present some applications of the code to challenging diatomic molecules
Soukup, Darin J. "A coupled local mode approach to laterally heterogeneous anisotropic media, volume scattering, and T-wave excitation /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/6847.
Повний текст джерелаCheung, Wai-kwong Andy, and 張偉光. "Investigation of probe insertion effects on plasma excitation conditions in direct sample insertion-inductively coupled plasmaatomic emission spectrometry." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45014747.
Повний текст джерелаCheung, Wai-kwong Andy. "Investigation of probe insertion effects on plasma excitation conditions in direct sample insertion-inductively coupled plasma atomic emission spectrometry /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31490955.
Повний текст джерелаJagau, Thomas-Christian [Verfasser]. "Higher-order molecular properties and excitation energies in single-reference and multireference coupled-cluster theory / Thomas-Christian Jagau." Mainz : Universitätsbibliothek Mainz, 2013. http://d-nb.info/1035840286/34.
Повний текст джерелаSamanta, Pradipta Kumar [Verfasser], and Andreas [Akademischer Betreuer] Köhn. "Excitation energies and response properties of molecules using internally contracted multireference coupled cluster methods / Pradipta Kumar Samanta ; Betreuer: Andreas Köhn." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2017. http://d-nb.info/1153008548/34.
Повний текст джерелаKottmann, Jakob Siegfried. "Coupled-Cluster in Real Space." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19357.
Повний текст джерелаIn this work algorithms for the computation of electronic correlation and excitation energies with the Coupled-Cluster method on adaptive grids are developed and implemented. The corresponding functions and operators are adaptively represented with multiresolution analysis allowing a basis-set independent description with controlled numerical accuracy. Equations for the coupled-cluster model are reformulated in a generalized framework independent of virtual orbitals and global basis-sets. For this, the amplitude weighted excitations into virtuals are replaced by excitations into n-electron functions which are determined by projected equations in the n-electron position space. The resulting equations can be represented diagrammatically analogous to basis-set dependent approaches with slightly adjusted rules of interpretation. Due to the singular Coulomb potential, the working equations are regularized with an explicitly correlated ansatz. Coupled-cluster singles with approximate doubles (CC2) and similar models are implemented for closed-shell systems and in regularized form into the MADNESS library (a general library for the representation of functions and operators with multiresolution analysis). With the presented approach electronic CC2 pair-correlation energies and excitation energies can be computed with definite numerical accuracy and without dependence on global basis sets, which is verified on small molecules.
Kurucu, Salur Riza. "A New Design Of Excitation Mechanism To Be Exploited By Modern Rf Excited Co2 Lasers." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605394/index.pdf.
Повний текст джерелаs progressed CO2 lasers on various power ranges. Though it could be used by a large variety of applications including RF plasma and RF heating, on the first occasion in order to define design considerations, this system is to be exploited by RF excited fast flow and RF excited slab CO2 laser constructions.
Frank, Marius Sebastian [Verfasser], Christof [Gutachter] Hättig, and Volker [Gutachter] Staemmler. "Implementation of coupled cluster excitation energies and gradients using pair natural orbitals / Marius Sebastian Frank ; Gutachter: Christof Hättig, Volker Staemmler ; Fakultät für Chemie und Biochemie." Bochum : Ruhr-Universität Bochum, 2021. http://d-nb.info/1240479395/34.
Повний текст джерелаBoztosun, Ismail. "Coupled-channels calculations for the scattering of deformed light heavy-ions : a challenge to the standard approach." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325373.
Повний текст джерелаHuiza, Juan Félix Pari. "Estudo do acoplamento dos canais diretos de reação nos sistemas 16,17,18O + 64Zn." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-14102010-135321/.
Повний текст джерелаExcitation functions for quasi-elastic scattering (elastic, inelastic and transfer) were measured for the 16O +64 Zn, 17O +64 Zn and 18O +64 Zn systems, at backward angles of 161º, in the laboratory reference system, and in the energy range between 30:0 and 46:0 MeV using steps of 0:5 and 1:0 MeV , for energies below and above the Coulomb barrier. Performing a derivative on experimental data we obtained the quasi-elastic barrier distributions for the three systems, which are equivalent to the fusion barrier distributions, and make evident the reaction mechanisms of the system. To obtain these data a good charge resolution \"Z\" of a gas proportional counter, E -E, was necessary and also the use of surface barrier detectors placed at forward angles, ±30º and -45167 for normalization. A theoretical analysis of the data was performed using the coupled reaction channel model CRC through the use of FRESCO [Thom 88] and CQUEL [Hagi 04] (a new version of CCFULL [Hagi 99]). To avoid the use of free parameters, in our calculations, we decided to use the real potential of the double-folding São Paulo Potencial [Cham 02], which describes physically the nucleus-nucleus interaction. It is based on Pauli non-locality and is characterized by the exchange of nucleons. The imaginary potential, responsible for the absorption of particles in a fusion process, was restricted to a very short range, and thus, it does not affect the quasi-elastic processes. In the theoretical analysis of the transfer excitation functions of one and two neutrons for the 17O+64Zn and 18O+64Zn systems, we obtained the spectroscopic information for some experimental states in 65Zn and 66Zn, which were used in the analysis of the excitation function and quasi-elastic barrier distributions for each system. The results obtained in these three systems are very interesting: the 16O +64 Zn system shows that the most important channels contributing to enhancement fusion cross section are the states 2+1 and 3-1 of the target [Huiz 07] (CQUEL), and the state 3-1 of the projectile (FRESCO). The 17O+64Zn system shows that the quadrupole and octupole excited states of the target, 2+ 1 and 3-1 , are strongly coupled to the elastic channel but it was necessary to couple the one neutron transfer channel in order to describe our data. Similarly, the 18O +64 Zn system confirmed that those two states of the target are strongly coupled to the two neutron transfer channel, but it was necessary to include in the coupling matrix the one neutron transfer channel. We verify that all these channels in the 18O +64 Zn describe the data and they in uence strongly the shape of the barrier distributions.
Simões, Rone Flávio. "Medidas das distribuições das barreiras de fusão para os sistemas 16,18O + 58,60Ni." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-18022014-153458/.
Повний текст джерелаExcitation functions for quasi-elastic scattering were measured with high precision with energy steps of 500 keV for the 16,18O + 56,60Ni systems. Fusion barrier distributions were extracted from the excitation functions. Coupled channel calculations were used in order to determine which channels are responsible for the structures observed in the experimental distributions. Two computation codes were used: CCFULL and FRESCO. Their results are similar. We compared Dfus with Dqe obtained with FRESCO and we have concluded that they are practically identical for all systems. This is a confirmation that the approximation Dfus = Dqe is reasonable in this mass region. The first conclusion with CCFULL code is that alpha stripping for the 16O + 58Ni system is the channel transfer most important at above barrier energies. However, the calculation with FRESCO showed that it has only minor importance. For the 16O + 60Ni system, the more expressive transfer channel is alpha pick-up. In the two other systems, 18O + 58,60Ni, we observed that one-neutron stripping has Strong influence on the barrier distributions. Beside the transfer channels, the target inelastic excitation is a very important reaction channel in all systems.
Janot, Alexander. "Quantum Condensates and Topological Bosons in Coupled Light-Matter Excitations." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-199239.
Повний текст джерелаNoga, Jozef, Stanislav Kedžuch, Ján Šimunek, and Seiichiro Ten-no. "Explicitly correlated coupled cluster F12 theory with single and double excitations." American Institite of Physics, 2008. http://hdl.handle.net/2237/12013.
Повний текст джерелаKiendl, Thomas [Verfasser]. "Low-energy excitations in strongly coupled superconductor-magnet hybrids / Thomas Kiendl." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1176638769/34.
Повний текст джерелаOhlsson, Sax Olof. "Spins and Giants : Fundamental Excitations in Weakly and Strongly Coupled ABJM Theory." Doctoral thesis, Uppsala universitet, Teoretisk fysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-151609.
Повний текст джерелаRust, Mike. "The Approximate Inclusion of Triple Excitations in EOM-type Quantum Chemical Methods." Scholarship @ Claremont, 2001. https://scholarship.claremont.edu/hmc_theses/135.
Повний текст джерелаComar, William D. Ph D. "ESTABLISHING AND MANIPULATING THE DIMERIC INTERFACE OF VISUAL/NON-VISUAL OPSINS." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron152882487417841.
Повний текст джерелаLuthra, Antriksh. "Mid-IR Plasmonics, Cavity Coupled Excitations, and IR Spectra of Individual Airborne Particulate Matter." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu148362252748271.
Повний текст джерелаFernique, François. "Collective plasmonic excitations in two- dimensional metamaterials based on near-field coupled metallic nanoparticles." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAE012/document.
Повний текст джерелаThe study of plasmonic properties is one of the fields of research currently very active. In particular, the ability to manipulate light at subwavelength scales makes this subject very appealing. Recently, several studies have shown that collective plasmons in two-dimensional meta-materials based on metallic nanoparticles behave similarly to electrons in crystals and share some of their properties. In this manuscript, we present a unified theory for describing the properties of such modes in regular arrays of arbitrary geometries constituted by near-field coupled spherical nanoparticles. In particular, we have evaluated the linewidths of these modes as well as their frequency shifts in order to discussed their experimental observabilities
Davison, Richard A. "Excitations in holographic quantum liquids." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:3b1db914-709e-41ec-ba7c-c968cb87b752.
Повний текст джерелаHuang, Ming-Hui. "Dynamic characteristics of slender suspension footbridges." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16450/1/Ming-Hui_Huang_Thesis.pdf.
Повний текст джерелаHuang, Ming-Hui. "Dynamic characteristics of slender suspension footbridges." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16450/.
Повний текст джерелаMerdan, Mohammad Ghanim Merdan. "Study of the excited states of the quantum antiferromagnets." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/study-of-the-excited-states-of-the-quantum-antiferromagnets(dfd01ec6-806c-464a-9b68-910217679c3c).html.
Повний текст джерелаOzdemir, Gokhan. "Response Of Isolated Structures Under Bi-directional Excitations Of Near-field Ground Motions." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12612039/index.pdf.
Повний текст джерелаRocha, Carlos Antonio da. "Medidas de seção de choque de fusão para os sistemas ANTPOT. 12 C + ANTPOT. 63, 65 CU." Universidade de São Paulo, 1987. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-01042014-093351/.
Повний текст джерелаIn this work we present cross-section measurements for nuclear fusion in the 12C+ 63,65 Cu system, at 12C energy range from 0.9 to 1.8 times the Coulomb barrier. In order to detect and to obtain the mass identification of the evaporation residues following the fusion process, the time of flight method was adopted in conjunction with an eletrostatic deflector capable of separating the evaporation residues from the beam particles. The limitation and advantadges of this method of measurement are discussed. The excitation functions for the above systems were analysed using the unidimensional barrier penetration model with different nuclear potentials. Theoretical fusion cross-section values obtained from this analysis were systematically smaller than our measured values, in the energy region below the Coulomb barrier. In order to discover which channel enhances the fusion cross-section in this region, a coupled channel calculation was performed, with the aid of CCFUS code. The experimental data for the above reactions were compared with the systems 12C+ 63,65 Cu, measured by our group. In this comparison, It was noted that the systems 12C+ 63,65 Cu have greater fusion cross section below the Coulomb barrier. This fact can be related to the static deformation of 12C. The comparison of velocity spectra of the evaporated residues for the two systems shows that 12C+63Cu has a strong reaction channel that was not present in the 12C+ 65Cu system.
Bouhafs, Nezha. "Excitation des hydrures d’azote par l’hydrogène atomique et moléculaire." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMLH15/document.
Повний текст джерелаObservation and study of interstellar molecular clouds require the knowledge of molecular data to derive the physical conditions (temperature, gas density, molecular abundance) of these media. Nitrogen hydrides are highly abundant species in the interstellar medium and they are found to be important reaction intermediates in the nitrogen chemistry. The interpretation of nitrogen hydrides observations from the HERSCHEL spatial observatory and the ALMA interferometer, requires accurate collisional rate coefficients of these molecules. The present thesis focuses on the determination of new rate coefficients for NH, NH2 and NH3 molecules in collision with Ne, H2 et H, respectively. Inelastic cross sections for the rotational excitation of all the studied systems have been computed with a close coupling method using the molecular dynamic codes MOLSCAT and HIBRIDON. The cross sections are then used to calculate the collisional rate coefficients for temperatures ranging from 5 to 200 K. The new rate coefficients were included in radiative transfer calculations in order to model the observed transitions of NH2 towards high-mass star-forming region W31C. We show that using the previously published rate coefficients instead of these new ones have a significant impact on the modeling, leading to important differences on the density, abundance and on the OPR of NH2. The new data will allow to put interesting constraints on the physical condition of the molecular cloud
Trippel, Richard [Verfasser], Robert [Akademischer Betreuer] Roth, and Achim [Akademischer Betreuer] Schwenk. "Collective Excitations with Chiral NN+3N Interactions from Coupled-Cluster and In-Medium SRG / Richard Trippel ; Robert Roth, Achim Schwenk." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/1122286414/34.
Повний текст джерелаJanot, Alexander [Verfasser], Bernd [Akademischer Betreuer] Rosenow, Bernd [Gutachter] Rosenow, and Ehud [Gutachter] Altman. "Quantum Condensates and Topological Bosons in Coupled Light-Matter Excitations / Alexander Janot ; Gutachter: Bernd Rosenow, Ehud Altman ; Betreuer: Bernd Rosenow." Leipzig : Universitätsbibliothek Leipzig, 2016. http://d-nb.info/1240398077/34.
Повний текст джерелаBricout, Marion. "Comportement du dioxyde d’uranium sous irradiation : effet couplé de l’endommagement nucléaire et des excitations électroniques." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASP064.
Повний текст джерелаDuring in-reactor operation, the nuclear fuel is exposed to the simultaneous radiation of fission fragments, alpha and beta decay, neutrons, etc. UO₂ fuel pellets are the site of a huge damage production, mainly due to the energy loss of fission products. At the atomic scale, low-energy particles lead to formation of collision cascade while the high-energy particles induce electronic excitation and ionisation. Defects such as cavities, dislocation lines and loops are produced in the fuel leading to a microstructural evolution. This evolution may then induce a swelling and/or a restructuration, which can affect the nuclear fuel integrity. Although ballistic and electronic-induced damages are separately well documented, the coupled effects between the two slowing-down processes are not well known.The aim of this study is to characterize these combined effects.Ion irradiations were conducted at the JANNus-Saclay and Orsay facilities with single and dual ion beams. Different complementary techniques were used to describe the microstructural evolution.Results show that both crystalline disorder and strain level are lower under dual-beam irradiation compared to the single one. The electronic energy deposition induce a decrease of point defects quantity as well as a transition from dislocation loops to lines. Some key parameters were highlighted during this study as the electronic excitation rate and the initial damage level.The observed phenomena on uranium dioxide led us to a better understanding of the UO₂ evolution under irradiation and more generally of the specific effects generated by dual-beam irradiations
Rocha, Rodrigo Tumolin [UNESP]. "On saturation phenomenon in energy harvesting based on nonlinear piezoelectric materials coupled to a portal frame foundation with ideal and non-ideal excitations." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143867.
Повний текст джерелаApproved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-13T13:55:19Z (GMT) No. of bitstreams: 1 tumolinrocha_r_dr_bauru.pdf: 13569204 bytes, checksum: 57c9cb53f7d15296a337d3d7544e5191 (MD5)
Made available in DSpace on 2016-09-13T13:55:19Z (GMT). No. of bitstreams: 1 tumolinrocha_r_dr_bauru.pdf: 13569204 bytes, checksum: 57c9cb53f7d15296a337d3d7544e5191 (MD5) Previous issue date: 2016-08-04
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Recentemente, o interesse e a pesquisa de coleta de energia têm aumentado substancialmente no meio técnico-científico. Com a grande demanda mundial por energia elétrica, muitos pesquisadores, no Brasil e no Mundo, têm concentrado seus esforços na busca de novas fontes de energia. Além disso, com os avanços da tecnologia, é possível utilizar dispositivos de baixo consumo de energia, que são, na maioria das vezes, alimentados por uma bateria, que são fontes de energia finita havendo a necessidade da recarga ou troca periodicamente, das mesmas. No processo de coleta de energia, a energia elétrica é obtida através da conversão de energia mecânica criada por uma fonte de vibração do meio ambiente através de um transdutor. Entre os mais comuns meios de transdução de energia, o uso de materiais piezoelétricos vêm sendo de grande interesse em meio a coleta de energia devido sua facilidade de aplicação e seu uso para coleta de energia em um amplo intervalo de frequências. Fontes de vibração do meio ambiente podem ser causadas em estruturas através do movimento de veículos, um trêm, ondas do mar e até o deslocamento de pessoas. Com isso, este trabalho tem como objetivo estudar a coleta de energia utilizando uma plataforma aporticada não-linear de dois graus de liberdade contendo um material piezoelétrico não-linear acoplado a uma de suas colunas e excitado externamente em sua base. A plataforma não-linear possui ressonância interna 2:1 entre seus modos de vibrar. A não-linearidade do material é considerada através de uma relação matemática não-linear. Além disso, este trabalho será separado em duas partes para a análise das excitações externas. Em sua primeira parte, considera-se uma força harmonica excitando sua base. Na segunda parte, será considerando um vibrador eletrodinâmico com saída harmônica. A metologia empregada para a realização das análises deste trabalho foram: utilizar o método de múltiplas escalas para buscar as melhores configurações dos parâmetros e encontrar fenômenos devido à ressonancia interna 2:1; em seguida foram realizadas excessivas simulações numéricas utilizando o método de Runge-Kutta de quarta e quinta ordem com passo variável buscando otimizar a coleta de energia através da variação de parâmetros, diagramas de bifurcação, expoente de lyapunov, FFTs e históricos no tempo e outros tipos de simulações. Em geral serão feitas duas comparações muito importantes. A influência da não-linearidade do material piezoelétrico e do uso da força harmonica e do vibrador eletrodinâmico na coleta de energia. Os resultados mostraram grande influência da não-linearidade do material piezoelétrico, e utilizando o vibrador foi possível ter um ganho considerável na estabilidade do sistema.
Recently, the interest and research about energy harvesting has been increasing substantially in the technical-scientific community. With the great world demand for electrical energy, many researchers, in Brazil and in the World, have concentrated their efforts to seek new energy sources. In addition, with the technological advances is possible to use low-power consumption devices, that are, most of time, powered by a battery, which are limited energy sources having the necessity of recharging or substituting them periodically. In the energy harvesting process, the electrical energy is obtained through the conversion of mechanical energy created by a vibrating source in the environment using a transducer. Among the most common energy transduction mean, the use of piezoelectric materials has been of great interest in the energy harvesting matter due to its ease of application and its use to harvest energy in a wide range of frequencies. Vibration sources in the environment may occur in structures by vehicle traffics, a train movement, sea waves and even people. With that, the objective of this work is to study the energy harvesting using a nonlinear two-degrees-of-freedom portal frame platform with a nonlinear piezoelectric material coupled to one of its columns and externally base-excited. The nonlinear platform possesses two-to-one internal resonance between its two vibration modes. The nonlinearities of the piezoelectric material is considered as a nonlinear mathematical relation. Moreover, this work is separated in two parts to the analysis of the external excitations. In the first part, a harmonic force base-exciting the system is considered. In the second part is considered an electro-dynamical shaker with harmonic output. The employed methodology to carry out the analysis of this work was: the application of the method of multiple scales to find the best configuration of the parameters, and to find some kind of phenomena due to the two-to-one internal resonance; in the following were carried out several numerical simulations using the method of Runge-Kutta of 4th and 5th order with variable step seeking to optimize the energy harvesting through parametrical variations, bifurcation diagrams, FFTs, time histories and other typos of simulations. In general, it will be done two much important comparisons: the influence of the nonlinearity of the piezoelectric material and the use of the harmonic force and the shaker to the energy harvesting. The results showed great influence of the nonlinearity of the material, and using the electro-dynamical device it was possible to have a considerably gain in the system stability.
Rocha, Rodrigo Tumolin. "On saturation phenomenon in energy harvesting based on nonlinear piezoelectric materials coupled to a portal frame foundation with ideal and non-ideal excitations /." Bauru, 2016. http://hdl.handle.net/11449/143867.
Повний текст джерелаBanca: Airton Nabarrete
Banca: Angelo Marcelo Tusset
Banca: Vinicius Piccirillo
Banca: Atila Madureira Bueno
Abstract: Recently, the interest and research about energy harvesting has been increasing substantially in the technical-scientific community. With the great world demand for electrical energy, many researchers, in Brazil and in the World, have concentrated their efforts to seek new energy sources. In addition, with the technological advances is possible to use low-power consumption devices, that are, most of time, powered by a battery, which are limited energy sources having the necessity of recharging or substituting them periodically. In the energy harvesting process, the electrical energy is obtained through the conversion of mechanical energy created by a vibrating source in the environment using a transducer. Among the most common energy transduction mean, the use of piezoelectric materials has been of great interest in the energy harvesting matter due to its ease of application and its use to harvest energy in a wide range of frequencies. Vibration sources in the environment may occur in structures by vehicle traffics, a train movement, sea waves and even people. With that, the objective of this work is to study the energy harvesting using a nonlinear two-degrees-of-freedom portal frame platform with a nonlinear piezoelectric material coupled to one of its columns and externally base-excited. The nonlinear platform possesses two-to-one internal resonance between its two vibration modes. The nonlinearities of the piezoelectric material is considered as a nonlinear mathematical r... (Complete abstract click electronic access below)
Resumo: Recentemente, o interesse e a pesquisa de coleta de energia têm aumentado substancialmente no meio técnico-científico. Com a grande demanda mundial por energia elétrica, muitos pesquisadores, no Brasil e no Mundo, têm concentrado seus esforços na busca de novas fontes de energia. Além disso, com os avanços da tecnologia, é possível utilizar dispositivos de baixo consumo de energia, que são, na maioria das vezes, alimentados por uma bateria, que são fontes de energia finita havendo a necessidade da recarga ou troca periodicamente, das mesmas. No processo de coleta de energia, a energia elétrica é obtida através da conversão de energia mecânica criada por uma fonte de vibração do meio ambiente através de um transdutor. Entre os mais comuns meios de transdução de energia, o uso de materiais piezoelétricos vêm sendo de grande interesse em meio a coleta de energia devido sua facilidade de aplicação e seu uso para coleta de energia em um amplo intervalo de frequências. Fontes de vibração do meio ambiente podem ser causadas em estruturas através do movimento de veículos, um trêm, ondas do mar e até o deslocamento de pessoas. Com isso, este trabalho tem como objetivo estudar a coleta de energia utilizando uma plataforma aporticada não-linear de dois graus de liberdade contendo um material piezoelétrico não-linear acoplado a uma de suas colunas e excitado externamente em sua base. A plataforma não-linear possui ressonância interna 2:1 entre seus modos de vibrar. A não-linearidade do... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor
Wang, Yuchen, Xiushan Zhu, Jie Zong, Kort Wiersma, Arturo Chavez-Pirson, Robert A. Norwood, and N. Peyghambarian. "SESAM Q-switched fiber laser at 1.2 mu m." IEEE, 2016. http://hdl.handle.net/10150/622787.
Повний текст джерелаNguyen, Tien Minh. "Dynamique non linéaire des systèmes mécaniques couplés: réduction de modèle et identification." Phd thesis, Ecole des Ponts ParisTech, 2007. http://pastel.archives-ouvertes.fr/pastel-00002994.
Повний текст джерелаLombana, Andrés Felipe. "Elaboration d'auto-assemblages supramoléculaires de Donneurs et Accepteurs d'électrons sur Au(111) et leur étude par microscopie à Effet Tunnel couplée à une excitation laser." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC069/document.
Повний текст джерелаWe present the 2D self-assembly of molecular electron Donors (D) and Acceptors (A) on Au(111) and their study by Light-Assisted Scanning Tunneling Microscopy (LA-STM). Firstly, hydrogen bonded supramolecular assemblies are elaborated from solutions. On one hand, a the self-assembly of a porphyrin derivative (D) show the relationship between the established hydrogen bonds and the obtained geometry. On the other hand, a PTCDI-melamine porous host network was used to template the growth of guest molecules within the pores. Host-guest systems are then elaborated using a thiolated porphyrin derivative and a polyoxometalate (POM) molecule. A surface infrared analysis (PM-IRRAS) shows that the network has different effects on the growth process and orientation angles of the two molecules.Secondly, we developed a LA-STM setup and we analysed a polymer/fullerene (PTB7/PC71BM) D/A molecular system. After the study of the photo-physical phenomena giving rise to the photo-current, we measured the current at opposite bias voltages DI=I(V+)-I(V-). We attribute this current to the photo-absorption of the molecules and to the electron transfer at the molecular D/A junctions which allows us to identify the active junctions on the surface with the nanometre resolution
Zekeng, Serge. "Diffusion Raman par les modes couples phonon-plasmon : application à GaAs dopé Si par implantation ionique : effet de la dose et du mode de recuit thermique." Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR13077.
Повний текст джерелаEl, Fallah Rawa. "Étude des interactions du Benzo(a)pyrène avec les trois fractions physiques de la matière organique du sol par matrices d'excitation et d'émission de fluorescence couplées à PARAFAC." Thesis, Perpignan, 2017. http://www.theses.fr/2017PERP0034/document.
Повний текст джерелаThe spectral properties of the fluorescent components of the organic matter of a natural soil were studied in the three physical fractions; humic substances, fulvic acid and humic acid, by the method of the excitation and fluorescence emission matrices coupled to the Parallel Factor Analysis (PARAFAC) algorithm. The spectral modifications of these components were studied (form and pseudo-concentrations) in the presence of a polycyclic aromatic hydrocarbon contaminant (benzo (a) pyrene (BaP), toxic and carcinogenic): (1) by varying the volumes of a pure solution of BaP in each fraction having the same concentration of organic matter, (2) by varying the concentrations of organic matter for fixed concentrations of BaP, which were followed over time. The results showed that the BaP influences the fluorophores present in the three fractions in a different way and clarified the type of interactions with one fraction or the other. On the other hand, a discussion was held on parameters for validating the number of components for the selection of PARAFAC models
Šikl, Tomáš. "Modelování dielektrických směrových odbočnic." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219120.
Повний текст джерелаBeckstein, Pascal. "Methodenentwicklung zur Simulation von Strömungen mit freier Oberfläche unter dem Einfluss elektromagnetischer Wechselfelder." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232474.
Повний текст джерела