Dissertations / Theses on the topic 'Excitation rates'
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Thorn, Penny Anne, and penny thorn@flinders edu au. "Electronic State Excitations in the Water Molecule by Collisions with Low Energy Electrons." Flinders University. Chemistry, Physics and Earth Sciences, 2008. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20080714.112505.
Full textBerejny, Philippe. "Excitation et ionisation multiphotoniques du xénon et des mélanges Kr - Xe. Etude du transfert d'énergie depuis l'état Kr2* [1u (3P1)]." Toulouse 3, 1993. http://www.theses.fr/1993TOU30193.
Full textLämsä, Karri. "GABAA receptor-mediated excitation in the hippocampus of adult and newborn rats." Helsinki : University of Helsinki, 2000. http://ethesis.helsinki.fi/julkaisut/mat/bioti/vk/lamsa/.
Full textSriratanaban, Chana. "Improved excitation techniques for fixed and variable rate CELP-based speech coding." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/843285/.
Full textKerfant, Benoît-Gilles. "Rôle des microtubules dans le couplage excitation-contraction de cardiomyocytes sains et hypertrophiés." Montpellier 2, 2002. http://www.theses.fr/2002MON20104.
Full textTurnidge, Martin Laurence. "Vibrational energy transfer at low temperatures and the use of infrared laser excitation for trace detection." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337427.
Full textDufour, Claude. "Interprétation du spectre électronique des monohalogénures de cuivre : transferts rotationnels induits par collisions inélastiques entre la molécule CaF (A2[Pi]) et les gaz rares." Lille 1, 1987. http://www.theses.fr/1987LIL10082.
Full textBouhafs, Nezha. "Excitation des hydrures d’azote par l’hydrogène atomique et moléculaire." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMLH15/document.
Full textObservation 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
Moutard, Pascal. "Dynamique et spectroscopie d'états atomiques ou moléculaires de gaz rares, obtenus par excitation à un ou plusieurs photons, simultanés ou séquentiels." Lyon 1, 1986. http://www.theses.fr/1986LYO10089.
Full textMark, Joshua F. "Analytical and Experimental Vibration Analysis of Variable Update Rate Waveform Generation." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1323882417.
Full textFernique, François. "Collective plasmonic excitations in two- dimensional metamaterials based on near-field coupled metallic nanoparticles." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAE012/document.
Full textThe 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
Ščerba, Andrius. "Asinchroninių generatorių tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110602_120403-93988.
Full textThe present work presents an experimental research of a three-phase induction generator which was connected using separate excitation and self-excitation schemes under various loads. The results of the research and the calculations are provided and analyzed. The research results obtained from the separately excited induction generator show that its energetic indicators are not significantly lower than the provided motor indicators. When the rated current In = 4,7 A flows through the windings of the generator, its released active power P2 = 2,6 kW is greater than the rated motor power Pn = 2,2 kW by 18,18 %. The research on a self-excited induction generator with a constant revolution speed (n = const) and capacity of its capacitors (C = const) shows that the energetic indicators of this generator are of significantly lower values than the provided motor indicators. When the load of the generator is increased, its phase voltage decreases rather rapidly. The maximum load current I1 = 2,68 A of the generator was measured under the following conditions: the rotational speed n = 2000 min-1 = const and the capacity of the capacitors C = 120 μF = const. The results showed that it was 43 % less than the rated motor current. Therefore, it can be concluded that a self-excited induction generator will not be exploited to its full capacity. The carried out research shows that it is possible to increase the load of a self-excited induction generator by increasing its voltage. It is... [to full text]
Moutard, Pascal. "Dynamique et spectroscopie d'états atomiques ou moléculaires de gaz rares, obtenus par excitation à un ou plusieurs photons, simultanés ou séquentiels." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375998980.
Full textRadouani, Abdelhak. "Réaction des atomes métastables de gaz rares (Ar*(3p2,0), Kr*(3p2) et Xe*(3p2)) avec le silane." Grenoble 1, 1986. http://www.theses.fr/1986GRE10143.
Full textBenmaamar, Ramla. "Role of neuropeptide Y and its receptors in the development of epileptogenesis in mice and rats." Université Louis Pasteur (Strasbourg) (1971-2008), 2003. http://www.theses.fr/2003STR13007.
Full textSebai, Sihem. "Synthèse et caractérisation de polyphosphates (Li/Na/K)(Y,La,Ln)(PO3)4 (Ln=Eu³⁺,Sm³⁺). Etude des propriétés de luminescence sous excitation VUV-UV." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC067/document.
Full textThis work is devoted to the development of phosphors based on polyphosphates of alkaline and rare earth ions, stoichiometric or activated with Eu3+ and Sm3+ ions, considered as light emitters under VUV excitation. These materials, with formula LixNa1-xY1-yEuy(PO3)4 (x = 0; 0.25; 0.5; 0.75; 1 and 0.01 ≤ y ≤ 1), LixNa1-xLa(PO3)4 : 5 % Eu3+ (x = 0; 0.1; 0.2; 0.8; 0.9; 1), NaxK1-xLa(PO3)4 : 5 % Eu3+ (x = 0; 0.1; 0.2; 0.8; 0.9; 1) and LixNa1-xSm(PO3)4 (x = 0; 0.5; 1), were synthesized in the solid state and characterized mainly by X-ray diffraction, infrared and Raman spectroscopies and thermal analysis. Physical-chemical and optical analyses, in particular using the Eu3+ ion as a structural probe, show that the cross-substitution of Li+, Na+ and K+ alkaline ions is possible only in a relatively small proportion, which is linked to the differences in crystallographic structures of these materials. The analysis of the Eu3+ ion spectroscopic data according to Judd and Ofelt theory confirms the close link between optical and structural properties in these materials. Excitation spectra are characterized by an intense band localized in the VUV domain, respectively due to the charge transfer mechanism Y3+-O2- and Eu3+-O2- for the Eu3+ doped yttrium materials and to the 4f-5d inter-configuration for the Sm3+ concentrated materials. Materials concentrated in Eu3+ and Sm3+ ions emit intense red and orange fluorescence respectively, demonstrating the absence of concentration quenching
Wang, Jing. "A Study of Limited-Diffraction Array Beam and Steered Plane Wave Imaging." University of Toledo / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1146240142.
Full textBeaulieu, Nathan. "Propriétés électroniques et magnétiques sous excitation laser femtoseconde, du Gd monocristallin aux alliages ferrimagnétiques." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00953656.
Full textJabbour, Georges. "Etude des excimères de krypton et de xénon par TALIF : applications aux décharges à barrière diélectrique dans le krypton." Toulouse 3, 2009. http://thesesups.ups-tlse.fr/697/.
Full textThis work deals about the study of reactionnal mechanisms of krypton excimers forming and the influence of the temperature on the formation of krypton and xenon excimers. These studies can account for the phenomena involved in a more complex (micro-discharges). The most recent experiments of the mechanisms of the formation of excimers (involve the study) of the fluorescence induced via the absorption of two (photons laser) (TALIF). This excitation technique permits to selectively populate the first two excited states of krypton and xenon from which are created the excimers emitting UVL radiation (excitation spectroscopy). The study of temporal LVU emissions of krypton was performed after selective settlement, either from the first metastable state Kr5s [3/2]o2 or from the first resonant state Kr5s [3/2]o1. The contribution of each of these statements in UVL emissions depending on pressure has been determined. The process leading to the formation of excimers was identified. The reaction rates of disappearance of resonant and metastable states caused by the collision of three body, was measured as the radiative lifetime of the excimer Kr2 (A1u). A transfer, from the resonant state towards the metastable state was highlighted. This enabled us to complete the kinetic patterns obtained in the group in previous studies. This study under selective excitation was followed by studying the influence of temperature on the formation of excimer krypton and xenon. It led to the determination of laws of constants variation of disappearance of the first metastable states of these gases depending on temperature. They show unambiguously that the reaction constants vary greatly depending on temperature. This is the basis of new data obtained for the first time in selective excitation. Spectroscopic and temporal studies conducted in selective excitation in krypton, permitted to interpret the measurements in a micro-discharge by the team. The electrical measurements are compared to those made in other rare gases in previous studies. The temporal and spectroscopic measurements were analyzed from those produced by laser-induced fluorescence
Ledru, Gérald. "Formation des excimères et exciplexes de gaz rares corrélés à l'état métastable Xe(3P2) peuplé sélectivement : application aux exciplexes KrXe dans une décharge à barrières diélectriques." Toulouse 3, 2005. http://www.theses.fr/2005TOU30132.
Full textThis concerns the study of formation and decay processes of Xe2 excimers and KrXe exciplexes corraled to the xenon 6s states. The elementaries processes leading to the VUV radiation emission have been study by populating selectively the 6s states of xénon ; these same emission were then observed in dielectrics barriers discharge. In order to study the reactional mechanisms under selective excitation, a new dye laser, pumped with a pulsed YAG, wich delivers 10 mJ in UV was used. This new excitation source made it possible to selectively populate the first two excited states of xenon from which are created the excimers emtting VUV radiation (excitation's spectroscopy). We could study the contribution of each one of these states in VUV emission versus the pressure (emission's spectroscopy). The temporal analysis of the luminescence carried out by populating the first resonant and metastable states enabled us to identify the processes leading to excimers formation and VUV radiation emission. A transfer from the resonant state towards the metastable state was highlighted and the transfer's constant has been determinated. This enabled us to supplement the kinetics schemes obtained in the team in former studies. This study under selective excitation continued in krypton-xenon mixtures by initially populating the two first excited states of xenon. Undes these conditions the emissions observed can come either from Xe2 molecule or KrXe molecule according to the partials pressures of the two gases. Spectroscopic and temporal measurements enabled us to identify the mixture's conditions in which the exciplexes KrXe emissions are observable. .
Merbahi, Nofel. "Luminescence de l'argon et du xénon dans les décharges à barrières diélectriques mono-filamentaires : analyses électriques et cinétique." Toulouse 3, 2004. http://www.theses.fr/2004TOU30261.
Full textAtmospheric pressure dielectric barrier discharge are more and more used in industry, in particular for ozone generation, surface treatment, material deposit, treatment of pollutants, production of ultraviolet radiation in excimer lamps, etc… At such high pressures, these discharges are generally filamentary, but under certain particular conditions they can be homogeneous. However, the reasons of the transition from one type to another are still badly known. Contrarily to the filament discharges, the homogeneous ones have been widely studied. So, for a better understanding of the behavior of filament discharges in rare gases, a new experimental device was designed in order to carry out the electrical and spectroscopic temporal analysis of a monofilament. The present study deals with pure argon and xenon. The temporal evolutions of both the current flowing through and the voltage drop across the micro-discharge, were calculated by using a macroscopic dynamic electrical model. The injected electric power as well as the ignition voltage was then deduced for various conditions. The establishment of the discharge was recorded: different phases namely, the initial electronic avalanche, followed by the positive streamer and then the formation of the cathode layer were clearly illustrated by short exposure-time snapshots in the visible range. .
Quichaud, Viviane. "Etude des processus elementaires : de synthese de la molecule no, en post-decharge en ecoulement, de collisions titane-gaz rares, titane-molecules, par perturbation laser resolue en temps." Paris 6, 1987. http://www.theses.fr/1987PA066135.
Full textCheng, Jiqi. "A Study of Wave Propagation and Limited-Diffraction Beams for Medical Imaging." University of Toledo / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1133820434.
Full textGofas, Salas Elena. "Manipulation of the illumination of an Adaptive Optics Flood Illumination Ophthalmoscope for functional imaging of the retina in-vivo High loop rate adaptive optics flood illumination ophthalmoscope with structured illumination capability In vivo near-infrared autofluorescence imaging of retinal pigment epithelial cells with 757 nm excitation." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS195.
Full textAs the only transparent optical window of our body, the eye gives a unique access to the observation of neural and vascular networks. Today however, a new era is opening up for high-resolution imaging, which should no longer be limited to giving access to tissue structures, but may also tackle their functions. In fact, biomarkers for the functioning of the whole human body can be found in retinal imaging. Neurodegenerative diseases (Parkinson's, Alzheimer's) or arterial hypertension could thus be diagnosed early by high precision imaging of the retina. In my thesis work, I intended to show how the full-field ophthalmoscope, associated to imaging modalities adjusting geometrical settings of the illumination, could contribute to research on the retina. To achieve this ambitious goal, we modified the full-field ophthalmoscope built at the National Hospital Center of Quinze-Vingts with a specific image processing and two new instruments inspired by full-field microscopy. We have integrated these instruments into the illumination path of the ophthalmoscope to manipulate the geometry of the retinal illumination. These new implementations allow us to make use of more advanced imaging techniques, such as dark field imaging or noninvasive near infrared angiography. These imaging modalities have been exploited to image the retina functionally. We focused mainly on the light coupling function of photoreceptors and on blood perfusion
Steveler, Émilie. "Etude des mécanismes de photoluminescence dans les nitrures et oxydes de silicium dopés aux terres rares (Er, Nd)." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0109/document.
Full textThis thesis is devoted to the study of radiative transitions in rare-earth (Er, Nd) doped silicon oxide and silicon nitride thin films. The optical characterization of thin films prepared by thermal evaporation is based on photoluminescence spectroscopy. In this work, we investigate indirect excitation processes of Er3+ and Nd3+ ions in silicon based materials. In silicon nitride and silicon oxinitride, an energy transfer leading to the indirect excitation of Er3+ ions is demonstrated. For amorphous samples, the sensitization of Er3+ ions is attributed to localized electronic states in the matrix bandgap. For samples annealed at high temperature, silicon nanocrystals play a major role in the indirect excitation of erbium. In silicon oxide thin films, we evidences that both direct and indirect excitation processes of Nd3+ ions occur. For amorphous samples, indirect excitation occurs thanks to localized electronic states in the matrix bandgap. For samples annealed at temperatures above 1000 °C, silicon nanocrystals are sensitizers of Nd3+ ions. Results suggest that indirect excitation thank to localized states in the matrix bandgap could be more efficient than indirect excitation thanks to silicon nanocrystals
Huang, Ming-Hui. "Dynamic characteristics of slender suspension footbridges." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16450/.
Full textZhang, Jiaxiang. "Single- and entangled-photon emission from strain tunable quantum dots devices." Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-177579.
Full textLÓPEZ, ORTIZ Javier del Cristo. "Estudo de propriedades magnéticas e excitações de spins em materiais ferromagnéticos e antiferromagnéticos." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/16560.
Full textMade available in DSpace on 2016-04-14T16:39:36Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese_final_biblioteca.pdf: 10701235 bytes, checksum: 1af9d6bb745e78ea9fe6b261b7baa59c (MD5) Previous issue date: 2015-05-08
Nesta tese tratamos teoricamente algumas propriedades magnéticas e excita c~oes de spins em materiais ferromagn eticos e antiferromagn eticos com o objetivo de interpretar as medidas e observa c~oes experimentais. Usamos a formula c~ao de ondas de spins de Holstein-Primako para investigar propriedades da din^amica de propaga c~ao de ondas de spins no material ferrimagn etico YIG e tamb em no sistema antiferromagn etico FeF2. Para cada um deles, desenvolvemos modelos te oricos que permitiram ajustar as rela c~oes de dispers~ao de ondas de spins medidas experimentalmente nesses. Al em disso, investigamos a renormaliza c~ao da energia de m agnons usando o formalismo das fun c~oes de Green de dois tempos dependentes da temperatura de Bogoliubov-Tyablikov. A aplica c~ao para o YIG, permitiu calcular as varia c~oes da rela c~ao de dispers~ao para m agnons com a temperatura. Tamb em se investigou a renormaliza c~ao da energia de m agnons no sistema FeF2, mas esta vez considerando uma aproxima c~ao do tipo RPA1. Na renormaliza c~ao da energia foram consideradas duas contribui c~oes: exchange isotr opica tipo Heisenberg e anisotropia uniaxial. Em nossas considera c~oes, foi inclu da a depend^encia com a temperatura da anisotropia uniaxial que permitiu estimar o campo critico de transi c~ao de spin- op para o limite de estabilidade da fase antiferromagn etica. Tamb em, foi feito um estudo te orico e experimental da anisotropia magneto cristalina do material antiferromagn etico RbMnF3, baseado nas intera c~oes de campo cristalino e intera c~ao de spin- orbita, com o objetivo de calcular a varia c~ao com a temperatura do campo de spin- op. As ondas de spins em YIG foram estudadas em mais detalhes calculando as taxas de relaxa c~ao por processos de espalhamento de 3-m agnons e 4-m agnons. Igualmente foram estimadas empregando campos magn eticos intensos da ordem de 102 kOe. Finalmente, estudamos propriedades t ermicas de transporte de m agnons em YIG submetido a campos magn eticos intensos. Calculamos o calor 1Random Phase Approximation especi co de m agnons e a condutividade t ermica em baixas temperaturas e campos magn eticos externos intensos para serem comparados com as medidas experimentais encontrando um bom acordo entre teoria e experimento [145]
In this thesis we theoretically treat some magnetic properties and excitations of spins in ferromagnetic and antiferromagnetic materials in order to interpret measurements and experimental observations. We use the formulation of quantization of spin waves of Holstein-Primako to investigate properties of the spin wave propagation dynamics in the ferrimagnetic material YIG and also in the antiferromagnetic system FeF2. For each of them, we have developed theoretical models to adjust the dispersion relations of spin waves measured experimentally in these systems. In addition, we investigated the magnon energy renormalization using the formalism of two-time temperature dependent Green's functions of Bogoliubov-Tyablikov. The application for the YIG allowed calculate the variation of the dispersion relation for magnons with temperature. We also investigate the magnon energy renormalization in the system FeF2, but this time considering an approximation of the RPA type. In the energy renormalization were considered two contributions: exchange isotropic Heisenberg and uniaxial anisotropy type. In our calculations the temperature dependence of the uniaxial anisotropy eld allows estimating the critical spin- op transition for the antiferromagnetic phase stability limit. Also, we have undertaken a theoretical and experimental study of the magneto crystalline anisotropy of the antiferromagnetic material RbMnF3, based on the crystal eld interactions and spin-orbit interaction, in order to calculate the variation with temperature of the eld spin- op. The spin waves in YIG were studied in more detail calculating the relaxation rate due to 3-magnons and 4-magnons scattering processes considering strong magnetic elds of hundreds of kOe. Finally, we have studied thermal transport properties of magnons in YIG subject to intense magnetic elds. We have, calculate of the speci c heat and thermal conductivity of magnons at low temperatures and high elds to compare with the experimental measurements nding a good agreement between theory and experiment [145].
Cunin, Bernard. "Etude et realisation d'un modulateur parametrique a double bande laterale fonctionnant a 10 ghz : application a la detection d'impulsions lumineuses breves." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13127.
Full textVivona, Marilena. "Radiation hardening of rare-earth doped fiber amplifiers." Thesis, Saint-Etienne, 2013. http://www.theses.fr/2013STET4008.
Full textThis thesis is devoted to the study of the radiation response of optical amplifiers based on Er/Yb doped fibers. These devices operating at 1.5 µm are conceived for space applications and contextually the evaluation of their performance in such harsh environment becomes of crucial importance. Two treatments, the H2-loading and the Ce-doping of the fiber core, are investigated as radiation hardening solutions. A spectroscopic study has been associated, in order to improve the knowledge of the physical mechanisms responsible for the signal degradation and the action of the hardening solutions. The thesis is organized in three parts. Part I deals with a general description of the Rare-Earth (RE)-doped fibers, with the introduction of some basic concepts of the RE-ion physics and their interaction with the host matrix material (phosphosilicate glass). The state-of-art of the radiation effects on the optical fibers, particularly the RE- doped fibers, is also overviewed. Part II describes the samples (fiber fabrication, geometry and chemical compositions), and the used experimental techniques, including a short discussion on the related theoretical background. Part III describes the main results; firstly, the active tests, performed on the RE-doped fiber as part of an optical amplifier, demonstrate that the Ce-codoping and H2-load have a key-role in the limitation of the radiation induced losses. Then, the spectroscopic analysis of the phosphosilicate glass (Raman study) and of the RE-ions (stationary and time-resolved luminescence) show a stabilization effect due to the two treatments, leading to a preservation of the high efficiency of the physical system under study
Astruc, Jean-Pierre. "Transfert d'électron entre atomes excités et molécules dans une expérience en jets croisés avec fluorescence résolue dans le temps." Paris 13, 1987. http://www.theses.fr/1987PA132020.
Full textSiegert, Wolfgang. "Local Lyapunov exponents : sublimiting growth rates of linear differential systems with random parameter excitation /." 2007. http://www.gbv.de/dms/ilmenau/toc/56082517X.PDF.
Full textShin-YiHuang and 黃馨儀. "R&D of High Frame-Rate Multiphoton Excitation Microscopy." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/73216599677933041641.
Full text國立成功大學
工程科學系
104
The invention of ultrafast-laser provides various applications for multiphoton microscopy in biomedical field. Recently, the resolution and frame rate of microscopy have great improvements. Confocal microscopy increases the 3D image contrast. The high speed scanning tools provide faster frame rate. In this research, we build a high temporal and spatial resolution multiphoton microscope based on high-speed 2D scanning method and we hope to increase frame rate for imaging cell dynamics. We adopt resonant galvanometer whose resonant frequency is 8 kHz to achieve rapid scanning speed in order to replace the traditional galvanometer. The system combines with the pixel clock board with the frequency ranges from 7.5 MHz to 15 MHz that contains scanning information of resonant galvanometer. Due to the fast sampling rate, we utilize FlexRIO which contains field-programmable gate array (FPGA) chip and high-speed data acquisition module to collect signal from galvanometers and to trigger photomultiplier tubes (PMT) to receive fluorescence signal. We use LabVIEW programming language of National Instruments (NI) to design overall system to process analog and digital signals, system parameters, and display images.
"A robust low bit rate quad-band excitation LSP vocoder." Chinese University of Hong Kong, 1994. http://library.cuhk.edu.hk/record=b5888223.
Full textThesis (M.Phil.)--Chinese University of Hong Kong, 1994.
Includes bibliographical references (leaves 103-108).
Chapter Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Speech production --- p.2
Chapter 1.2 --- Low bit rate speech coding --- p.4
Chapter Chapter 2 --- Speech analysis & synthesis --- p.8
Chapter 2.1 --- Linear prediction of speech signal --- p.8
Chapter 2.2 --- LPC vocoder --- p.11
Chapter 2.2.1 --- Pitch and voiced/unvoiced decision --- p.11
Chapter 2.2.2 --- Spectral envelope representation --- p.15
Chapter 2.3 --- Excitation --- p.16
Chapter 2.3.1 --- Regular pulse excitation and Multipulse excitation --- p.16
Chapter 2.3.2 --- Coded excitation and vector sum excitation --- p.19
Chapter 2.4 --- Multiband excitation --- p.22
Chapter 2.5 --- Multiband excitation vocoder --- p.25
Chapter Chapter 3 --- Dual-band and Quad-band excitation --- p.31
Chapter 3.1 --- Dual-band excitation --- p.31
Chapter 3.2 --- Quad-band excitation --- p.37
Chapter 3.3 --- Parameters determination --- p.41
Chapter 3.3.1 --- Pitch detection --- p.41
Chapter 3.3.2 --- Voiced/unvoiced pattern generation --- p.43
Chapter 3.4 --- Excitation generation --- p.47
Chapter Chapter 4 --- A low bit rate Quad-Band Excitation LSP Vocoder --- p.51
Chapter 4.1 --- Architecture of QBELSP vocoder --- p.51
Chapter 4.2 --- Coding of excitation parameters --- p.58
Chapter 4.2.1 --- Coding of pitch value --- p.58
Chapter 4.2.2 --- Coding of voiced/unvoiced pattern --- p.60
Chapter 4.3 --- Spectral envelope estimation and coding --- p.62
Chapter 4.3.1 --- Spectral envelope & the gain value --- p.62
Chapter 4.3.2 --- Line Spectral Pairs (LSP) --- p.63
Chapter 4.3.3 --- Coding of LSP frequencies --- p.68
Chapter 4.3.4 --- Coding of gain value --- p.77
Chapter Chapter 5 --- Performance evaluation --- p.80
Chapter 5.1 --- Spectral analysis --- p.80
Chapter 5.2 --- Subjective listening test --- p.93
Chapter 5.2.1 --- Mean Opinion Score (MOS) --- p.93
Chapter 5.2.2 --- Diagnostic Rhyme Test (DRT) --- p.96
Chapter Chapter 6 --- Conclusions and discussions --- p.99
References --- p.103
Appendix A Subroutine of pitch detection --- p.A-I - A-III
Appendix B Subroutine of voiced/unvoiced decision --- p.B-I - B-V
Appendix C Subroutine of LPC coefficients calculation using Durbin's recursive method --- p.C-I - C-II
Appendix D Subroutine of LSP calculation using Chebyshev Polynomials --- p.D-I - D-III
Appendix E Single syllable word pairs for Diagnostic Rhyme Test --- p.E-I
"Traumatic Brain Injury Induces Rapid Enhancement of Cortical Excitability in Juvenile Rats." Master's thesis, 2014. http://hdl.handle.net/2286/R.I.25879.
Full textDissertation/Thesis
Masters Thesis Biology 2014
SHiu, Shiou-Jr, and 徐秀枝. "Transmission Rate Enhancement of Disk Drive System Subjected to Base Excitation at Different Inclined Angles." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/16913159168573670674.
Full text大同大學
機械工程學系(所)
96
Due to the progress of information technology, multimedia information products need high performance promotion and improvement. The storage device of computer information product becomes a basic equipment nowadays. It brings convenience (e.g. ATM, Pronunciation service system, Easy card automated system, etc) to our life. Industry computer plays an important role in the business. The computer not only has simple function, but also controls the whole operation flows in the factory. Hence, it can not be interrupted or crashed during the operation. And the computer must have high storage system with security and stability. Therefore an anti-vibration mounting is needed unlike the personal computer. The mounting protect the data transmission to avoid date lost from interrupted or crashed by external power or vibration of machine operating. This thesis is to investigate the effect of the transmission efficiency when the disk system (hard disk) is reading at acclivitous angle. The performance of transmission efficiency has been noted when the disk system subjected by the vibration at different inclined angles. The method can be discussed into two parts. Firstly, compare with different angle, different vibration level, and different vibration rate, the transmission efficiency has good results when it is 160Hz, any angles, Isolator 20A. Secondly, the transmission efficiency has better effect when it is 160Hz , at any angle, complex Isolator 8A40A at different angle, different vibration level, different vibration rate comparability with different complex Isolator. At last, comparing with different angle, different vibration level different vibration rate, different Isolator VS different angle, different vibration level, different vibration rate, different complex Isolator, the best transmission efficiency is 160Hz, at any angle, complex Isolator 8A40A.
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