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Dissertations / Theses on the topic 'Electrodynamic'
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Deckert, Dirk-André. "Electrodynamic absorber theory." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-114215.
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Chang, Chung-Jen. "Electrodynamic behavior of PMG-Delta." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA283930.
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Endacott, Christopher John. "Studies on electrodynamic crop spraying." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47423.
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Carlson, Andrew F. "Optimal orbit maneuvers with electrodynamic tethers." Thesis, Monterey, Calif. : Naval Postgraduate School, 2006. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Sep%5FCarlson.pdf.
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Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, June 2006.<br>Thesis Advisor(s): Ross, I. Michael ; Danielson, Don A. "June 2006." Description based on title screen as viewed on November 7, 2007. Includes bibliographical references (p. 65-67). Also available in print.
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Barraclough, Timothy Luke. "The electrodynamic response of unconventional superconductors." Thesis, University of Birmingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433702.
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Deux, Jean-Marie A. "Kinetic modeling of electrodynamic space tethers." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32451.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005.<br>Includes bibliographical references (p. 190-193).<br>Electrodynamic space tethers provide propellant-less orbit boosting and de-orbiting of Low Earth Orbit (LEO) satellites. On the one hand, when driven by a current, their interaction with the Earth's magnetic field creates a thrusting Lorentz force. On the other hand, current can be collected from the ionospheric electrons, which also creates a drag. Although the principle is simple, one theoretical issue still has to be addressed: How much current is collected in realistic LEO conditions by a tether of a given section and potential ? The current theories of current collection fail to explain in-space experimental results and previous kinetic modeling was limited from the computational and physical standpoints: wake partly outside the simulation domain, artificial ion/electron mass ratios, single tether, etc. In the present work we improve our computational techniques and physical model to simulate the tether interaction with the ionosphere. We built a full PIC code which allows to study realistic configurations with the 3V modelling of plasma-probe interactions in external and self-induced magnetic fields. The model uses real electron-ion mass ratio and can simulate domains larger than the wake created in a flowing plasma, thanks to the implementation of a Fast Poisson Solver. Multiwire modelling is available as well to study the interference and efficiency of parallel tether array configurations. The theory of current collection has then been further developed, by showing the existence of electron trapping around the probe, and evaluating the consequences on current collection. This analysis was supported and discussed through several simulations ran with the PIC code.<br>(cont.) We will present results of kinetic studies of current collection for different tether bias, shapes and configurations, including orbit visualizations and statistical diagnostics. Our numerical results will be compared to existing theories of current collection by a moving wire in the OML regime [4]. Eventually, results outside this restricted regime, which are not predicted accurately by any theory, will be discussed.<br>by Jean-Marie A. Deux.<br>S.M.
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Lechelon, Mathias. "Long-range electrodynamic interactions among biomolecules." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0469/document.
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L’étude des organismes vivants, la biologie, s’étend sur de nombreux domaines et notamment s’applique à comprendre le fonctionnement des êtres vivants. Les organismes les plus complexes comme les êtres Humains possèdent plusieurs niveaux d’organisation : ils sont constitués successivement d’organes, de tissus, de cellules, de biomolécules. On trouve plusieurs types de biomolécules dont les protéines, qui sont comme des minuscules outils qui permettent aux cellules de vivre et d’interagir avec leur environnement. Pour cela, les protéines doivent entrer en contact les unes avec les autres de manière très précise et déterminée. Cette thèse teste l’existence de forces électrodynamiques de longue portée qui leur permettraient d’interagir de manière rapide et guidée, via l’étude de l’absorption ou l’émission de ce type d’onde par des protéines, puis la diffusion de ces protéines en solution pour observer leur comportement<br>The study of living organisms, biology, extends over many fields and in particular, applies to understanding the functioning of living beings. The most complex organisms, such as human beings, have several levels of organization: they are made up successively of organs, tissues, cells, and biomolecules. There are several types of biomolecules including proteins, which are like tiny tools that allow cells to live and interact with their environment. To do this, proteins must come into contact with each other in a very precise and determined way. This thesis tests the existence of long-range electrodynamic forces which would allow them to interact in a rapid and guided way, by studying the absorption or emission of this type of wave by proteins, then the diffusion of these proteins in solution to observe their behavior
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Martini, Luca. "Real-time control of an Electrodynamic Shaker." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10080/.
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Questa tesi è essenzialmente focalizzata sullo sviluppo di un sistema di controllo in tempo reale per uno Shaker Elettrodinamico usato per riprodurre profili di vibrazione ambientale registrati in contesti reali e di interesse per il recupero di energia. Grazie all'utilizzo di uno shaker elettrodinamico è quindi possibile riprodurre scenari di vibrazione reale in laboratorio e valutare più agevolmente le prestazioni dei trasduttori meccanici. Tuttavia, è richiesto un controllo dello Shaker non solo in termini di stabilità ma anche per garantire l'esatta riproduzione del segnale registrato nel contesto reale. In questa tesi, si è scelto di sviluppare un controllo adattivo nel dominio del tempo per garantire la corretta riproduzione del profilo di accelerazione desiderato. L'algoritmo è stato poi implementato sul sistema di prototipazione rapida dSPACE DS1104 basata su microprocessore PowerPC. La natura adattiva dell'algoritmo proposto permette di identificare cambiamenti nella risposta dinamica del sistema, e di regolare di conseguenza i parametri del controllore. Il controllo del sistema è stato ottenuto anteponendo al sistema un filtro adattivo la cui funzione di trasferimento viene continuamente adattata per rappresentare al meglio la funzione di trasferimento inversa del sistema da controllare. Esperimenti in laboratorio confermano l'efficacia del controllo nella riproduzione di segnali reali e in tipici test di sweep frequenziale.
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Caccavano, Adam. "Optics and Spectroscopy in Massive Electrodynamic Theory." Thesis, Portland State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1549591.
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<p> The kinematics and dynamics for plane wave optics are derived for a massive electrodynamic field by utilizing Proca's theory. Atomic spectroscopy is also examined, with the focus on the 21 cm radiation due to the hyperfine structure of hydrogen. The modifications to Snell's Law, the Fresnel formulas, and the 21 cm radiation are shown to reduce to the familiar expressions in the limit of zero photon mass.</p>
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Macdonald, H. M. "Analysis and control of an electrodynamic shaker." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1353.
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Rahi, Sahand Jamal. "Scattering theory approach to electrodynamic Casimir forces." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62652.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2010.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 117-123).<br>We give a comprehensive presentation of methods for calculating the Casimir force to arbitrary accuracy, for any number of objects, arbitrary shapes, susceptibility functions, and separations. The technique is applicable to objects immersed in media other than vacuum, nonzero temperatures, and spatial arrangements in which one object is enclosed in another. Our method combines each object's classical electromagnetic scattering amplitude with universal translation matrices, which convert between the bases used to calculate scattering for each object, but are otherwise independent of the details of the individual objects. The method is illustrated by rederiving the Lifshitz formula for infinite half spaces, by demonstrating the Casimir-Polder to van der Waals cross-over, and by computing the Casimir interaction energy of two infinite, parallel, perfect metal cylinders either inside or outside one another. Furthermore, it is used to obtain recent results: the Casimir energies of i) a sphere or ii) a cylinder opposite a plate, all with finite permittivity and permeability, to leading order at large separation, iii) a parabolic cylinder opposite a plate, both representing perfect metal boundaries, and iv) a sphere or spheroid inside a cavity, where both the inside object and the cavity walls have realistic material properties. We also examine whether electrodynamic Casimir forces can lead to stable levitation. Neglecting permeabilities, we find that any equilibrium position of objects subject to such forces is unstable if the permittivities of all objects are higher or lower than that of the enveloping medium; the former being the generic case for ordinary materials in vacuum.<br>by Sahand Jamal Rahi.<br>Ph.D.
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Petrovskyi, Mykhailo Vasylovych, Михайло Васильович Петровський, and Михаил Васильевич Петровский. "Electrodynamic properties of defects in photonic crystals." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/64229.
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Now the electrodynamic systems of terahertz range devices are being improved due to the rapid development of synthetic material media possessing the property of periodicity in several directions which are call photonic crystals. The implementation of field interaction of photonic crystals with electron beams or dielectric waveguides is based on the formation of linear disturbances of their periodicity, these disturbances having strongly expressed waveguide properties.
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McDowall, Stephen R. "An electrodynamic inverse problem in chiral media /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/5768.
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Caccavano, Adam. "Optics and Spectroscopy in Massive Electrodynamic Theory." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1485.
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The kinematics and dynamics for plane wave optics are derived for a massive electrodynamic field by utilizing Proca's theory. Atomic spectroscopy is also examined, with the focus on the 21 cm radiation due to the hyperfine structure of hydrogen. The modifications to Snell's Law, the Fresnel formulas, and the 21 cm radiation are shown to reduce to the familiar expressions in the limit of zero photon mass.
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Musso, Andrea. "Losses in electrodynamic transient in superconducting Rutherford cables." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12875/.
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The implementation of a continuum model for the simulation of interstrand coupling currents and the corresponding AC losses in superconducting Rutherford cables, due to electrodynamic transients, is performed. To obtain the necessary level of detail, the electrical model takes into account possible longitudinal variations of the contact conductance. A convergence study is performed to derive the minimum number of mesh elements required. The model is validated comparing loss values per cable twist pitch with the ones obtained through analytical formulae present in literature; an excellent agreement is found. Conclusions are drawn regarding the choice of the boundary conditions and the minimum length of the cable sample, to simulate the behavior of real long cables. In order to suppress losses, a resistive core is inserted in the cable and this strategy is implemented in the model. Induced currents and losses distributions in cables with core are derived and compared with the uncored case; conclusions are drawn about the choice of core width, placement and electrical resistance, to maximize its effect. The model presented is suitable to simulate cables behavior with or without core and subjected to uniform time-varying magnetic fields, considering different geometrical and electrical characteristic.
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Prance, H. "Quantum electrodynamic duality in superconducting weak link circuits." Thesis, University of Sussex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370437.
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Rosenberg, Max. "Comparative Analysis of Electrodynamic Toroidal Radiation Shielding Configurations." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1963.
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Beyond the protective confines of Earth's atmosphere and magnetosphere, spacecraft are subject to constant bombardment by high-energy charged particles originating from our Sun in the form of Solar Particle Events (SPEs), and from outside the solar system in the form of Galactic Cosmic Rays (GCRs). The harm these particles do can be reduced or mitigated outright through radiation shielding. Because protons and other charged particles comprise most of these radiation particles, strong magnetic fields could be generated around spacecraft to deflect incoming charged radiation particles. This thesis investigates the performance of specific configurations of toroidal superconducting solenoids to generate magnetic fields that deflect incoming energetic protons via the Lorentz force. Bulk material shielding configurations using various thicknesses of liquid water are similarly investigated, as are combination shielding configurations combining the best-performing toroidal shielding configurations with a small bulk material shield surrounding the spacecraft.
The water shielding configurations tested included shields of uniform thicknesses from 1 cm to 10 cm surrounding an Apollo CSM-sized cylindrical candidate spacecraft. Water shielding was found to be very effective at reducing the SPE dose, from a 86\% reduction at 1 cm of water to a 94\% reduction at 10 cm. However water shielding was found to be minimally effective against the much higher energy Galactic Cosmic Ray protons, with no dose reduction at 1 cm and a paltry 1\% reduction at 10 cm.
The toroidal shielding geometric configurations tested consisted of either 5 or 10 primary toroidal shields surrounding the candidate spacecraft, as was the addition of smaller nested toroidal shields inside the primary toroids and of toroids on the spacecraft's endcaps. The magnetic field strengths tested were 1.7 Tesla, 8.5 Tesla, and 17 Tesla. The best geometric configurations of electrodynamic shielding consisted of 5 primary toroidal shields, 5 total nested shields placed inside the primary toroids, and 2 total shields on the spacecraft's endcaps. The second best geometric configuration consisted of 10 primary toroidal shields plus two total endcap shields. These configurations at 1.7 Tesla reduced the SPE dose by 87\% and 87\%, and reduced the GCR dose by 11\% and 10\%. At 17 Tesla, these configurations both reduced the SPE dose by 90\%, and reduced the GCR dose by 76\% and 61\%. Combining these two configurations with a 1 cm-thick shield of water improved performance against SPE protons to 95\% and 93\% at 1.7 Tesla, and a 97\% and 96\% reduction at 17 Tesla. GCR dose reductions decreased slightly.
Passive material shielding was found capable of providing substantial protection against SPE protons, but was minimally effective against GCR protons without very thick shielding. Electrodynamic shielding, at magnetic field strengths of 1.7 Tesla, was found to be similarly effective against SPE protons, and marginally more effective against GCR protons. Combining the best toroidal shielding configurations, at magnetic field strengths of 1.7 Tesla, with water shielding yielded high protection against SPE protons, but still marginal protection against GCR protons. Increasing the magnetic field strength to 17 Tesla was found to provide very high protection against SPE protons, and to significantly reduce the radiation dose from GCR protons. Of all shielding configurations tested, only those electrodynamic configurations with magnetic fields of 17 Tesla were able to reduce the GCR dose by more than half.
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Bitzer, Matthew Scott. "Optimal Electrodynamic Tether Phasing and Orbit-Raising Maneuvers." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32766.
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We present optimal solutions for a point-mass electrodynamic tether (EDT) performing phasing and orbit-raising maneuvers. An EDT is a conductive tether on the order of 20 km in length and uses a Lorentz force to provide propellantless thrust. We develop the optimal equations of motion using Pontryagin's Minimum Principle. We find numerical solutions using a global, stochastic optimization method called Adaptive Simulated Annealing. The method uses Markov chains and the system's cost function to narrow down the search space. Newton's Method brings the error in the residual to below a specific tolerance. We compare the EDT solutions to similar constant-thrust solutions and investigate the patterns in the solution space. The EDT phasing maneuver has invariance properties similar to constant-thrust phasing maneuvers. Analyzing the solution space reveals that the EDT is faster at performing phasing maneuvers but slower at performing orbit-raising maneuvers than constant-thrust spacecraft. Also several bifurcation lines occur in the solution spaces for all maneuvers studied.<br>Master of Science
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ROTH, II RICHARD ALLAN II. "PERFORMANCE AND MODELING OF ULTRALINEAR ELECTRODYNAMIC ACTUATOR SYSTEMS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085751811.
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Fitzpatrick, Michele. "Electrodynamic driver for the space thermoacoustic refrigerator (STAR)." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23204.
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Approved for public release; distribution is unlimited<br>The objective of the STAR project is to test and space qualify a new continuous cycle cryogenic refrigeration system for cooling of sensors and electronics which is based upon the newly discovered thermoacoustic heat pumping effect. The new refrigerator has no sliding seals, a cycle frequency of about 300 hz, and uses acoustic resonance to enhance the overall power density and efficiency. This thesis is concerned specifically with the design and testing of the electrodynamic transducer which is responsible for the electro-acoustic power conversion. A computer model of the driver/resonator system is presented along with the techniques for measurement of the electrical and mechanical parameters used as input for the model. A final driver design (including dimensional drawings) utilizing a modified JBL 2450J neodymium-iron-boron compression driver and associated leak tight electrical feed-throughs, microphone, accelerometer, pressure gage, pressure housing, and resonator interface is provided. Keywords: Electrodynamic loudspeaker, Thermoacoustic refrigerator<br>http://archive.org/details/electrodynamicdr00fitz<br>Lieutenant, United States Coast Guard
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Darnley, Richard Vincent Bernard. "Electrodynamic guiding and deceleration of polar diatomic molecules." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/8640.
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This thesis reports on the properties of an alternating gradient guide and decelerator for heavy polar diatomic molecules, 179Yb19F and 40Ca19F, in the ground ro-vibrational and electronic state. A study of clustering was undertaken pointing to a link between cluster formation and the molecular beam intensity. A cold (-3 K) supersonic beam of CaF molecules was developed for these experiments. We studied the guiding properties of the Stark decelerator over a wide range of parameters. encompassing different voltages, molecular beam speeds and species. Transmission of molecules through the decelerator was compared with various theoretical predictions, and agreement was found only when a full 3-dimensional finite-element map of the electrostatic field of the lenses was considered. A localized strengthening of the defocusing force was found at the entrance and exit of the lenses. This defocusing field gradient, brought oil by the nonzero longitudinal gradient in the fringe fields, is an inherent property of our two-electrode lens design. A better, four-electrode lens geometry is suggested. A universal scaling, applicable to harmonic lenses, was found. This allowed direct comparison between all the experimental and simulated transmission data, and worked remarkably well even when anharmonic and fringe field effects were significant. Some residual discrepancies remain to be understood. YbF molecules have been decelerated, demonstrating an increased loss in kinetic energy (13cA) over previous published results, and for the first time, we have decelerated (accelerated) CaF demonstrating a 10% loss (gain) in kinetic energy. The deceleration data agree with the expected energy loss, and also demonstrate the effect of longitudinal bunching. We have observed and understood a further loss of transmission when molecules are strongly decelerated. This is due to a decrease of the confining potential in the axial direction. The proposed 4-electrode decelerator is expected to produce more decelerated molecules.
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Mantellato, Riccardo. "Investigation of Deorbiting Systems using Passive Electrodynamic Propulsion." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424284.
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In the last decade, the continuous and alarming growth of space debris prompted many space agencies all over the world to adopt debris mitigation strategies. Present guidelines indicate the need to deorbit new satellites launched into low Earth orbit (LEO) within 25 years from their end of life. At present, a space-proven technology suitable to carry out a complete deorbit utilizes classical chemical propulsion. However, a deorbit
maneuver by means of chemical rocket strongly affects the satellite propulsion budget, thus limiting the operational life of the satellite. These issues bring the need to develop innovative deorbiting technologies. One of these consists in using electrodynamic tethers that, through its interaction with the Earth ionosphere and magnetic field, can take advantage of Lorentz forces for deorbiting. Previous studies have shown the effectiveness of such a technology to deorbit LEO satellites from different altitudes and inclinations in a relatively short time. This work addresses some of the issues of deorbit systems based on electrodynamic tether systems. First, a passive elastic-viscous damping device installed at the attachment point of the tether to the spacecraft is studied to damp the low and yet continuous injection of energy into the system produced by
Lorentz forces that, in the long run, can bring the tether to instability. Second, the issues related to the in-orbit deployment of a tape-shaped tether from a non-tumbling spacecraft are attacked to find simple and
effective solutions. The chosen strategy is to deploy a tethered tip mass following a pre-determined flight path fed forward to a linear proportional-derivative closed-loop control operated by a brake system mounted on
the deployer reel. Lastly, an optimization process for bare electrodynamic tether systems has been developed. The analysis focuses on the deorbiting performances of electrodynamic tether systems from LEO high ranking hot spot regions (e.g., sun-synchronous orbits), and includes a realistic mass budget of a deorbiting system suitable for small satellites.<br>La continua ed allarmante crescita del numero di detriti spaziali avvenuta negli ultimi dieci anni ha spinto le agenzie spaziali di tutto il mondo ad adottare specifiche strategie di mitigazione. Le attuali linee guida internazionali indicano la necessità di far deorbitare i nuovi satelliti lanciati in orbita terrestre bassa (LEO) entro 25 anni dalla fine della loro vita operativa. Attualmente, i sistemi basati sulla propulsione chimica costituiscono l'unica tecnologia spaziale collaudata adatta ad effettuare un deorbiting completo di un satellite. Tuttavia, l'utilizzo di razzi per una manovra deorbitante richiede un considerevole quantitativo di propellente, andando ad influenzare fortemente il budget di massa del satellite, limitandone così la vita operativa. Ciò porta alla necessità di sviluppare tecnologie innovative per il rientro a fine vita di satelliti. Una di queste consiste nell'utilizzo di fili elettrodinamici che, attraverso l'interazione con la ionosfera e il campo magnetico terrestre, sfruttano le forze di Lorentz per effettuare il rientro. Studi precedenti hanno dimostrato l'efficacia di tale tecnologia per il deorbiting di satellite in LEO da diverse altezze e inclinazioni orbitali in un tempo relativamente breve. Questo lavoro di tesi affronta alcuni dei problemi caratteristici dei sistemi di deorbiting basati su sistemi a filo elettrodinamico. Innanzitutto, è stato studiato l'impiego di un sistema viscoelastico passivo da installare in corrisponenza dell'interfaccia
tra filo e satellite. Questo sistema è stato ideato per smorzare il flusso di energia prodotto dalle forze di Lorentz che continuamente entra nel sistema e che, a lungo andare, può portare il tether all'instabilità dinamica. In secondo luogo, si è affrontato il problema relativo al dispiegamento in orbita di un filo a forma di nastro (tape tethers) da un veicolo spaziale il cui assetto è noto. La strategia scelta è quella di
dispiegare dal satellite-base un sub-satellite seguendo una traiettoria predefinita, facendo uso di un sistema di controllo in retroazione lineare proporzionale-derivativo operato da un impianto frenante montato sull'albero del sottosistema di dispiegamento. Infine, è stato sviluppato un processo di ottimizzazione per sistemi a filo elettrodinamico. L'analisi si concentra sulle prestazioni dei sistemi elettrodinamici per il deorbiting di satelliti di piccola taglia (Small Satellites) da orbite LEO appartenenti a regioni sensibili (ad esempio, le orbite polari eliosincrone). Il processo di ottimizzazione è anche in grado di fornire un mass budget realistico del sistema di rientro.
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Lea, Stephen Nicholas. "Measurements of quantum-electrodynamic effects in highly-ionised atoms." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302897.
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Karshenas, Amir Masood. "Random vibration and shock control of an electrodynamic shaker." Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/1170.
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Berlin, Shaena R. (Shaena Rochel). "An electrodynamic balance (EDB) for extraterrestrial cloud formation studies." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90650.
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Thesis: S.M. in Atmospheric Sciences, Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2014.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 42-48).<br>Ice clouds scatter and absorb solar radiation, affecting atmospheric and surface temperatures (Gettelman et al., 2012). On Mars, where ice contained in clouds makes up a large portion of total atmospheric water vapor, ice clouds also alter the planetary water budget (Maltagliati et al., 2011; Rafkin et al., 2013). Thus, it is important for climate models to be able to accurately predict the conditions under which ice clouds can form. Typical Martian temperatures at cloud-formation height range from -150-200 K (Trainer, Toon, & Tolbert, 2009). Heterogeneous deposition nucleation is thought to be the dominant freezing mechanism on Mars due to the abundance of mineral dust to serve as ice nuclei (IN) (Mdittanen et al., 2005). The parameters for such nucleation are not well characterized at such low temperatures (Trainer et al., 2009). Previous experimental studies have investigated the relative humidity required for deposition nucleation within the Martian temperature range. However, most studies took place on bulk aerosol samples, did not use mineral dusts analogous to Martian dust, or were constrained by particle lifetime and temperature limits. In this project, we re-purpose a single-particle instrument and set it up to perform experiments for more precise ice nucleation data under Martian atmospheric conditions. We use an electrodynamic balance (EDB) to levitate individual particles with diameters around 10 pm. We calculate the size of the particle and changes in size based on the holding voltages. The system can be cooled to 200 K in its current configuration, and the relative humidity and atmospheric constituents can be controlled by adding gas. To test the EDB, we perform validation experiments. We investigate deliquescence and efflorescence on salts at room temperature and 0 'C. We modify the cooling system, thermocouples, and relative humidity sensors and begin freezing experiments with Arizona Test Dust (ATD) and with Mojave Mars Simulant (MMS) dust. We investigate water uptake on MMS particles and find it to be non-hygroscopic but wettable, uptaking monolayers of water between 65-95% relative humidity. From 200 K to 220 K, MMS does not nucleate up to 115% RHice, suggesting that higher supersaturations are needed for ice clouds to form; some Martian cloud modelers should revisit the critical supersaturation parameterization. Future work will improve the EDB and use it to examine phase functions and light scattering.<br>by Shaena R. Berlin.<br>S.M. in Atmospheric Sciences
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Bidin, Abdul Rahman. "Electrodynamic sensors and neural networks for electrical charge tomography." Thesis, Sheffield Hallam University, 1993. http://shura.shu.ac.uk/19355/.
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This research into the feasibility of imaging particulate processes using electrical charge tomography investigates four techniques: the multi-sensing of electrical charge in a cross-section, a neural network based classifier for flow regime identification, cross correlation based velocity determination and spectral analysis of electrodynamic signals. A single charged-particle model is developed to simulate the induction effect on a sensor by a charge. The spatial representation of the voltage induced onto sixteen sensors, placed on the boundary of a circular pipe, gives a flow distribution profile over the cross-section. A two charged-particle model is developed to simulate the electrodynamic effect of two particles on a tomographic sensor configuration. As in the single particle model, a spatial representation of the voltages induced onto the sensors is presented. This voltage profile is due to the combined effects of position and charge of the two particles. A multi-particle model is developed to predict the voltage profile of several flow regimes: full, annular, core, half and stratified. The model is extended to provide the loading and concentration of a given flow. A measurement system is constructed consisting of sixteen sensors equally spaced around the boundary of a circular 100mm pipe. Measurements on a bead drop system are designed to verify the single particle model. A sand flow system, consisting mainly of 300 micron sized particles, is used for measurements of the induced voltages due to different flow regimes. The latter are created artificially by using baffles of different shapes that obstruct the sand flow. The voltage profile from the sixteen sensors gives spatial information about the flow regime. These voltage profiles are normalised into patterns that are presented to a Kohonen neural network for classification. Two regime classification between well differentiated regimes gives an accuracy of identification of 95%. This is expanded to provide classification of three regimes with more variability in the input patterns giving success rates between 50% to 70%. A power spectral density analysis of the measured electrodynamic signals gives observable features for particle characterisation during flow. In full flow, with no baffles obstructing the sand flow, a consistently high frequency spectra of 550Hz is observed. At flow rates above 0.540 kgs-1, the frequency spectra shifts to a lower range of 200Hz. In obstructed flow, such as in stratified regime, an inhomogeneous phase is inferred from the drop in frequency of the power spectra at relatively low flowrates (0.36kgs-1). These results suggest a relationship between the observed spectra and the phenomenon of clustering of particles at higher concentrations. The potential of electrodynamic spectroscopy for particle characterisation in terms of size distribution is discussed. Knowledge of flow regime voltage profile, regime identification and concentration provided a basis for an empirically based image reconstruction algorithm. Finally the achievements of the thesis are discussed and suggestions made for further work.
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Aghdaei, Sara. "Electrodynamic droplet actuation for lab on a chip system." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/177577/.
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This work presents the development of electrowetting on dielectric and liquid dielectrophoresis as a platform for chemistry, biochemistry and biophysics. These techniques, typically performed on a single planar surface offer flexibility for interfacing with liquid handling instruments and performing biological experimentation with easy access for visualisation. Technology for manipulating and mixing small volumes of liquid in microfluidic devices is also crucially important in chemical and biological protocols and Lab on a Chip devices and systems. The electrodynamic techniques developed here have rapid droplet translation speeds and bring small droplets into contact where inertial dynamics achieve rapid mixing upon coalescence. In this work materials and fabrication processes for both electrowetting on dielectric and liquid dielectrophoresis technology have been developed and refined. The frequency, voltage and contact angle dependent behaviour of both techniques have been measured using two parallel coplanar electrodes. The frequency dependencies of electrowetting and dielectrophoretic liquid actuation indicate that these effects are high and low-frequency limits, respectively, of a complex set of forces. An electrowetting based particle mixer was developed using a custom made electrode array and the effect of varying voltage and frequency on droplet mixing was examined, with the highest efficiency mixing being achieved at 1 kHz and 110 V in about 0.55 seconds. A composite electrodynamic technique was used to develop a reliable method for the formation of artificial lipid bilayers within microfluidic platforms for measuring basic biophysical aspects of cell membranes, for biosensing and drug discovery applications. Formation of artificial bilayer lipid membranes (BLMs) was demonstrated at the interface of aqueous droplets submerged in an organic solvent-lipid phase using the liquid dielectrophoresis methods developed in this project to control the droplet movement and bring multiple droplets into contact without coalescence. This technique provides a flexible, reconfigurable method for forming, disassembling and reforming BLMs within a microsystem under simple electronic control. BLM formation was shown to be extremely reliable and the BLMs formed were stable (with lifetimes of up to 20 hours) and therefore were suitable for electrophysiological analysis. This system was used to assess whether nanoparticle-membrane contact leads to perturbation of the membrane structure. The conductance of artificial membranes was monitored following exposure to nanoparticles using this droplet BLM system. It was demonstrated that the presence of nanoparticles with diameters between 50 and 500 nm can damage proteinfree membranes at particle concentrations in the femtomolar range. The effects of particle size and surface chemistry were also investigated. It was shown that a large number of nanoparticles can translocate across a membrane, even when the surface coverage is relatively low, indicating that nanoparticles can exhibit significant cytotoxic effects
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Cohen, Mark D. Seinfeld John H. Flagan Richard C. "Studies of concentrated electrolyte solutions using the electrodynamic balance /." Diss., Pasadena, Calif. : California Institute of Technology, 1987. http://resolver.caltech.edu/CaltechETD:etd-03202008-105002.
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Brohede, Ulrika. "Drug Diffusion and Nano Excipient Formation Studied by Electrodynamic Methods." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7818.
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Pomarnacki, Raimondas. "Investigation of the electrodynamic retard devices using parallel computer systems." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20120106_101019-38158.
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An analysis using numerical methods can calculate electrical and construction characteristics parameters of microwave devices quite accurately. However, numerical methods require a lot of computation resources and time for calculations to be made. Rapid perfection of the computer technologies and software with implementation of the numerical methods has laid down the conditions to the rapid design of the microwave devices using computers.<br>Disertacijoje nagrinėjamos mikrobangų įtaisų analizės ir sintezės proble-mos, taikant lygiagrečiąsias kompiuterines sistemas. Pagrindiniai tyrimo objektai yra daugialaidės mikrojuostelinės linijos ir meandrinės mikrojuostelinės vėlinimo linijos. Šie objektai leidžia perduoti, sinchronizuoti bei vėlinti siunčiamus signalus ir yra neatsiejama dalis daugelio mikrobangų prietaisų. Jų operatyvi ir tiksli analizė bei sintezė sąlygoja įtaisų kūrimo spartinimą. Pagrindinis disertacijos tikslas – sukurti lygiagrečiąsias metodikas ir algoritmus, skirtus sparčiai ir tiksliai atlikti minėtų linijų analizę ir sintezę. Sukurtų algoritmų ir metodikų taikymo sritis – mikrobangų įtaisų modeliavimo ir automatizuoto projektavimo progra-minė įranga.
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Ajangnay, Martino Ojwok Ajang. "Adaptive shock control of an electrodynamic shaker with nonlinear loads." Thesis, Heriot-Watt University, 2004. http://hdl.handle.net/10399/368.
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Dalley, James. "The electrodynamic entrapment and manipulation of microparticles for environmental analysis." Thesis, University of Hertfordshire, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431940.
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Ferry, Jean-Benoît 1979. "Electron collection by an electrodynamic bare tether at high potential." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/82762.
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Widmann, John F. "Chemical reaction and thermodynamic studies of microparticles using electrodynamic balances /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9873.
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Lembke, Torbjörn A. "Design and analysis of a novel low loss homopolar electrodynamic bearing." Doctoral thesis, KTH, School of Electrical Engineering (EES), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-185.
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<p>A novel homopolar electrodynamic bearing, together with a suitable permanent magnet drive, have been developed for high-speed applications where low losses and high reliability are essential and exclude the use of ball bearings, and yet where active magnetic bearings offer a too complex system solution. Considered applications are small turbomolecular vacuum pumps, and maintenance free flywheels for energy storage in remote telecom and satellite systems. Other upcoming areas where these bearings offer interesting technical and economic solutions are compressors for fuel cells and heat pumps, applications which normally suffer from short bearing lifetime.</p><p>Unlike active magnetic bearings, forces are produced in electrodynamic bearings without any control electronics, thanks to stabilizing eddy currents induced by permanent magnets. In the novel homopolar concept eddy current losses are reduced to a minimum using a homopolar design with ring magnets instead of multipole or Halbach arrays.</p><p>Currents and forces are simulated using steady state 3D-FEM analysis, which can take velocity into account using an implemented Minkowski transform. From these results an analytical model has been developed, and the results are compared. The results are converted into useful rotordynamic data that is easily understood by machine engineers.</p><p>The bearing has been experimentally tested in a rebuilt turbomolecular vacuum pump up to 90,000 rpm. Bearing forces have been accurately measured on a specially designed spring suspended scales, in which the bearing rotor is powered with the permanent magnet drive. Comparison of measured data with results from the 3D-FEM analysis shows excellent agreement.</p>
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Lembke, Torbjörn A. "Design and analysis of a novel low loss homopolar electrodynamic bearing /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-185.
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Eriksson, Tobias J. R. "Development of piezoelectric and electrodynamic flexural transducers for air-coupled ultrasonics." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/91284/.
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Phased array ultrasound transducers could offer significant benefits over single element transducers in flow metering technology. By steering the ultrasonic beam transmitted through the flow, a single pair of phased array transducers have the potential to replace several pairs of traditional single element transducers. A first step in researching the potential for phased array transducers in flow meters is to investigate a suitable array element. Flexural ultrasound transducers use the bending modes in a thin plate to generate ultrasound waves in low impedance media, such as liquids and gases. The behaviour of piezoelectric flexural transducers was studied using theoretical modelling, finite element (FE) modelling and experimental techniques. Some focus was put on characterising the passive layer of the transducer, which was shown to be largely responsible for the flexural behaviour. That is, the dimensions of the passive layer largely determined the resonance frequencies of the flexural vibration modes of the transducer. Also, the viability of flexural transducers for flow applications was assessed. A new method of constructing air-coupled ultrasound phased array transducers was suggested. A 3 x 3 array was constructed and tested. The individual elements of the array behaved as single element flexural transducers, but the system as a whole could be improved to allow for better beam shaping. A novel electrodynamic flexural transducer (EDFT) for air-coupled ultrasonic transduction without use of piezoelectric materials was proposed, developed and experimentally tested. The transducer combines the contactless coupling method used by electromagnetic acoustic transducers (EMATs) with the flexural vibration modes of a thin plate to transmit and receive ultrasound waves in air. The output pressure of the transducers was high, with SPLs over 100 dB, but the sensitivity was low compared to piezoelectric transducers.
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MacLachlan, Amy Jane. "Control, manipulation and exploitation of electromagnetic radiation using complex electrodynamic structures." Thesis, University of Strathclyde, 2015. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=26567.
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Wang, Joseph Jiong. "Electrodynamic interactions between charged space systems and the ionospheric plasma environment." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13895.
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Dudek, David Robert. "Single particle, high temperature, gas-solid reactions in an electrodynamic balance." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/39089.
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Holmström, Caroline. "Modeling and Compensation of Nonlinear Distortion in High Efficient Electrodynamic Loudspeakers." Thesis, Luleå tekniska universitet, Signaler och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81219.
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Loudspeakers transform electrical energy into acoustic waves but most of the electrical energy is lost as heat. It is possible to increase the electro-acoustic efficiency by changing the electrical, mechanical or acoustical design of the loudspeaker but with these changes come unwanted side effects. An efficient loudspeaker exhibits strongly nonlinear behavior, but the nonlinear effects can be reduced by the means of implementing an algorithm on a digital signal processor. This is of great interest for Axis Communications since it makes it possible to increase the efficiency in their products without loss of sound quality. The purpose of this thesis was to investigate nonlinear distortion in high efficient electrodynamic loudspeakers using a simulation software, COMSOL Multiphysics, and to model the nonlinear response of the loudspeaker behavior. The simulations were conducted in order to get an understanding of the nonlinear behavior but also to estimate data for the theoretical model. Further, a nonlinear model describing the voice coil excursion was investigated with the purpose of constructing a nonlinear filter able to reduce nonlinear distortion. The result of the simulation showed it was possible to estimate the force factor as a function of voice coil displacement and that it also should be possible, according to the magnetic fields and streamlines, to obtain the function that describes the voice coil inductance from the same simulation of the loudspeaker. The numerical implementation of the voice coil excursion showed the voice coil was operating in the wrong domain when it was driven with a real input signal. Hence, the Volterra series need further work before a nonlinear filter can be derived.
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Musso, Andrea <1991>. "Analysis of electrodynamic transients in High Temperature Superconducting tapes and coils." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9687/1/Musso_PhD_Thesis.pdf.
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This thesis deals with the losses generated during electrodynamic transients in second generation High Temperature Superconductors (HTS). The various aspects are first investigated at the conductor level and then extended to coils wound with such tapes.
Two numerical models are presented to investigate losses in coated conductors due to a combination of an AC transport current and an AC magnetic field. The first model implements a FEM analysis based on the H-formulation, while the second one implements an integral analysis based on the A-V formulation. Furthermore, a methodology is presented to determine the influence of the configuration of the voltage measurement circuit on the AC losses measured in tapes, calculating a corrective factor to be applied to the experimental results.
Then, an electromagnetic methodology and a post-processing technique for the acquired signals are developed to measure the AC losses in different tapes. The method does not involve the use of lock-in amplifiers and has some advantages over traditional techniques.
Whereupon, the defect-irrelevant behaviour of a no-insulation (NI) HTS coil in a pancake-wound configuration, in which some defects are intentionally inserted at desired locations, is verified. The results of the experiments carried out at different temperatures are treated to determine the parameters of a simple equivalent circuit.
Secondly, the electrical characteristics of two HTS coils in a layer-wound configuration, with and without insulation and having almost identical geometric parameters, are compared. The distinct electric field profiles acquired during tests are explained by the use of an equivalent lumped parameter circuit, which allows to derive the current distribution between the turns.
Finally, the same layer-wound coils are supplied with an AC current and their power dissipation is measured experimentally. The measurements are discussed and correlated with the results obtained through two models which can describe the different power dissipation mechanisms involved.
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Curreli, Davide. "Analysis, simulation and testing of advanced electrodynamic systems for space propulsion." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3421628.
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Helicon plasma sources are an attractive means of plasma production in advanced applications of space propulsion thanks to their high ionization efficiency. By means of a compact helicon source, it is possible to enhance the performances of a small propulsive apparatus from a range of almost negligible values (few micro-Newton of thrust and few tens of seconds of specific impulse) to a range useful for many applications (thrust of milli-Newton and 1000s seconds of specific impulse). However, the design of such a system is complicated by the great inter-correlations between the involved parameters, and by the complex physical mechanisms involved. Moreover, thruster operation involve physical regimes which are not common in industrial plasma sources. In this research program, helicon physics has been deeply analyzed in a innovative way, not limiting the study to helicon wave analysis with dielctric tensors, but recognizing that the electromagnetic wave propagation must be closely related to macroscopic transport. An equilibrium theory of an helicon discharge has been derived, where both the plasma-wave local coupling of the RF antenna field with the plasma, and the transport of plasma species at the macroscopic level, are considered. The theory has been practically implemented on a code and validated with experiments in Laboratory. The theory has allowed to close the correlations between the design parameters and to identify preliminary design configurations of helicon thrusters.<br>Grazie alla loro elevata efficienza, le sorgenti al plasma di tipo helicon sono un attraente mezzo di produzione di plasma per applicazioni avanzate di propulsione spaziale. Per mezzo di una compatta sorgente helicon, è possibile incrementare le prestazioni di un piccolo apparato propulsivo, da un range di valori pressoché trascurabili (pochi micro-Newton di spinta e qualche decina di secondi di impulso specifico) ad un range utile per molte applicazioni (spinta del milli-Newton e migliaia di secondi di impulso specifico). Tuttavia il design di un tale sistema è complicato dalla grande inter-correlazione tra i parametri coinvolti, e dai complessi meccanismi fisici coinvolti. Inoltre il regime operativo del thruster avviene in regimi fisici non comuni per plasmi di sorgenti industriali. In questo programma di ricerca la fisica fondamentale degli helicon è stata attentamente studiata, non limitando le analisi al problema di accoppiamento d'onda con tensore dielettrico, ma riconoscendo che il problema elettromagnetico è strettamente connesso al traporto macroscopico. E' stata sviluppata una teoria dell'equilibrio di una scarica helicon, dove sono tenuti in considerazione sia l'accoppiamento locale plasma-onda del campo RF (radiofrequenza) dell'antenna con il plasma, che il trasporto delle specie di plasma a livello macroscopico. La teoria è stata implementata in un codice e validata con esperimenti in Laboratorio. La teoria ha permesso di chiudere le correlazioni fra i parametri di design e di identificare delle configurazioni preliminari di propulsori helicon.
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Branch, Jane Varpu. "Transport studies of the integer and fractional quantum Hall effects." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276529.
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Jentschura, Ulrich [Verfasser]. "Quantum Electrodynamic Bound-State Calculations and Large-Order Perturbation Theory / Ulrich Jentschura." Aachen : Shaker, 2003. http://d-nb.info/1174514426/34.
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Storm, Markus Erasmus. "The application of electrodynamic levitation in magnetic bearings / by Markus E. Storm." Thesis, North-West University, 2006. http://hdl.handle.net/10394/65.
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Currently the MBMC (Magnetic Bearing, Modelling and Control) research group in the School
of Electrical, Electronic and Computer Engineering of the North-West University is developing a
Magnetic Bearing research laboratory. The aim is to ascertain a proper knowledge and
understanding of magnetic bearings for development and implementation in industry. Magnetic
levitation can be realised through using either EMS (Electromagnetic Suspension) which
functions on attracting forces or EDS (Electrodynamic Suspension) that functions on repulsive
forces. Since all the research done by the MBMC research group were until now focused on
EMS AMBs (Active Magnetic bearings) there was a need to also explore the possibilities of an
EDS implementation.
The project objectives are the design and verification of a vertically suspended EDS magnetic
bearing laboratory model. Different possible methods of EDS exist and by studying each the
most promising alternative was selected, the Inductrack technique. A combination of a special
high grade permanent magnet arrangement, the Halbach array, and a unique conducting track
construction forms the Inductrack concept. This method uses electrodynamic interaction between
a moving Halbach array and a close-packed array of coils consisting of shorted electrical circuits
to attain levitation. The lnductrack technique must be revised into a circular implementation to
realize a functioning magnetic bearing since the method was developed for magnetically
levitated trains.
This involves altering the linear Halbach array and conducting track into circular elements with
the same levitation characteristics. Since exceptionally little literature could be found on this
specific implementation it was decided that the project will not entail the physical building of a
demonstration model. However, the focus of the project was to create a sound design foundation
and to veri@ the applicability of the design in magnetic bearings. Attaining this knowledge
involved the all the design phases of a laboratory demonstration model except that the model was not physically built and implemented. The revised design was verified by analytical calculations, MATLAB@ simulations and
comparing the system parameters with a linear Inductrack scale model. The circular Halbach
array implementation was verified by using two different FEM (Finite Element Method)
software packages and performing several 2D and 3D simulations. The magnets should be
specially assembled into the circular array through a complex process due to the immense
strength of the magnets. Since no information is available on this, the process was uniquely
developed through using a FEM analysis to determine the forces present between the permanent
magnets within the array during the assembly process. An assembly model was developed and
the assembly process simulated in the CAD software package SOLIDWORKS@ to eliminate
any interference.
A mechanical design was performed on the different model parts and was used to combine the
assembly and demonstration model. This was done by using analytical calculations and
incorporating a stress and strain analysis with SOLIDWORKS@a nd COSMOSX~~~SASf@ter. t he
different design sections of the project were completed a design review board meeting was held.
The purpose of this meeting was to evaluate and verify the different aspects of the project and to
obtain inputs where possible improvements could be made. Due to the diversity of the project
(including electrical to mechanical aspects) members from both disciplines constituted the
review panel. The design was approved by the review panel with minor implementation
recommendations.<br>Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2006.
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Davila-Smith, Luciana C. "Permanent dipole moments and damping in nonlinear optics : a quantum electrodynamic description." Thesis, University of East Anglia, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323293.
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Erickson, Daniel S. "Fabrication and cost analysis of screen-printed electrodynamic shields for solar applications." Thesis, Boston University, 2013. https://hdl.handle.net/2144/21148.
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Thesis (M.Sc.Eng.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.<br>Electrodynamic Shields (EDS) have been targeted as a technology to help mitigate degradation of power output caused by dust deposition on various solar collectors. Though printed circuit board based EDS prototypes have shown promising dust removal efficiencies, an inexpensive method of transparent EDS fabrication must be realized before the EDS technology is adopted by the solar industry. Development of a screen-printing process is presented as a scalable, low-cost method of EDS fabrication. The process is established using a silver-based ink on borosilicate glass substrates and then adapted to incorporate transparent conductive PEDOT:PSS and ITO nanoparticle solutions. Successful EDS prototypes are characterized and integrated with photovoltaic cells and second surface mirrored substrates. Removal efficiencies of the screen-printed EDS are tested by measuring the restoration in specular reflection and transmission in integrated EDS-mirror and EDSPV modules after dust depositions. Finally, a cost analysis of the EDS screen-printing process is performed in order to predict the economic viability of the EDS technology when used in conjunction with solar collecting technologies.<br>2031-01-01
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Jentschura, Ulrich D. [Verfasser]. "Quantum Electrodynamic Bound-State Calculations and Large-Order Perturbation Theory / Ulrich Jentschura." Aachen : Shaker, 2003. http://nbn-resolving.de/urn:nbn:de:101:1-2018123004421660355078.
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Wilder, Frederick Durand. "The Non-Linear Electrodynamic Coupling Between the Solar Wind, Magnetosphere and Ionosphere." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/26586.
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The polar electric potential imposed on the ionosphere by coupling between the earthâ s magnetosphere and the solar wind has been shown to have a non-linear response to the interplanetary electric field (IEF). This dissertation presents an empirical study of this polar cap potential saturation phenomenon. First, the saturation of the reverse convection potential under northward is demonstrated using bin-averaged SuperDARN data. Then, the saturation reverse convection potential is shown to saturate at a higher value at higher solar wind plasma beta. The reverse convection flow velocity is then compared with cross-polar cap flows under southward IMF under summer, winter and equinox conditions. It is demonstrated that the reverse convection flow exhibits the opposite seasonal behavior to cross polar cap flow under southward IMF. Then, an interhemispheric case study is performed to provide an explanation for the seasonal behavior of the reverse convection potential. It is found using DMSP particle precipitation data that the reverse convection cells in the winter circulate at least partially on closed field lines. Finally, SuperDARN and DMSP data are merged to provide polar cap potential measurements for a statistical study of polar cap potential saturation under southward IMF. It is found that the extent of polar cap potential saturation increases with increasing Alfvenic Mach number, and has no significant relation to Alfven wing transmission coefficient or solar wind dynamic pressure.<br>Ph. D.