Dissertations / Theses on the topic 'MHD'
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Paulovčák, Ján. "Sledování pohybu v MHD." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2017. http://www.nusl.cz/ntk/nusl-363878.
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This master’s thesis is dedicated to user’s movement tracking in public transport, as well as to optimize route planning. In the first part, author presents information related to graph theory and graph theory algorithms, including Breadth-First Search, Djikstra’s algorithm and A*. In the second part of this thesis, author describes the design of server and mobile application including description of routing process and how individual parts works.
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Jírová, Viktorie. "Netradiční systém MHD - TVR." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-75363.
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This Master's Thesis deals with unconventional systems od public transport - TVR. The first part describes the theoretical foundation for the installation and functioning the public transport counting the technical requirements. The second part deals with unconventional systems, so called Tramways on tyres, which is run by two models - system Translohr and TVR. The Master's Thesis is focused on the economical and technical evaluation of each types of the public transport, mainly of the TVR, which is operated only in two cities over the world.
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Kriške, Petr. "Anamorfní mapy v MHD." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226227.
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This diploma thesis is focused on creating schematic maps and their using in public transport system. It describes methods of making and individual variations of these maps. Further, the thesis is trying to evaluate and classify the available czech and world cartographic works with this content. Based on this analysis are proposed the new alternative solutions of schematic map in public transport in Nový Jičín.
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GIANTESIO, Giulia. "MHD stagnation-point flow." Doctoral thesis, Università degli studi di Ferrara, 2013. http://hdl.handle.net/11392/2388856.
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The flow near a stagnation-point is a fundamental topic in fluid dynamics and it has
been studied by several researches during the past decades because of its relevant
applications.
In this Thesis we investigate the influence of the electromagnetic field on the
stagnation-point flow of a Newtonian or a micropolar fluid. To this end we consider
three types of such a motion: plane orthogonal, plane oblique and three-dimensional.
We take into consideration a fluid which moves towards a flat surface.
We descrive several situations which are relevant from a physical point of view when
an external uniform or not uniform electromagnetic field is impressed.
Actually, we have prove that if the external magnetic field is uniform and the induced
magnetic field is neglected, then the stagnation-point flow exists if, and only, if
the external magnetic field has some suitable directions. Further, we compute the
induced magnetic field in the other cases.
We prove also that if the external magnetic field is not uniform and it is parallel to
the velocity at infinity then the three-dimensional stagnation-point flow is possible
if and only if it is axisymmetric.
In all the cases here considered, the MHD PDEs which govern the motion are
reduced to a system of nonlinear ODEs. These boundary values problems are then
integrated numerically and some graphics and tables are furnished in order to show
the behaviour of the solution near the obstacle.
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Cerfon, Antoine Julien. "Analytic calculations of MHD equilibria and of MHD stability boundaries in fusion plasmas." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/76494.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references.
In this work, two separate aspects of ideal MHD theory are considered. In the first part, analytic solutions to the Grad-Shafranov equation (GSE) are presented, for two families of source functions: functions which are linear in the flux function T , and functions which are quadratic in T. The solutions are both simple and very versatile, since they describe equilibria in standard tokamaks, spherical tokamaks, spheromaks, and field reversed configurations. They allow arbitrary aspect ratio, elongation, and triangularity as well as a plasma surface that can be smooth or possess a double or single null divertor X-point. The solutions can also be used to evaluate the equilibrium beta limit in a tokamak and spherical tokamak in which a separatrix moves onto the inner surface of the plasma. In the second part, the reliability of the ideal MHD energy principle in fusion grade plasmas is assessed. Six models are introduced, which are constructed to better describe plasma collisonality regimes for which the approximations of ideal MHD are not justified. General 3-D quadratic energy relations are derived for each of these six models, and compared with the ideal MHD energy principle. Stability comparison theorems are presented. The main conclusion can be summarized in two points. (1) In systems with ergodic magnetic field lines, ideal MHD accurately predicts marginal stability, even in fusion grade plasmas. (2) In closed field line geometries, however, the ideal MHD predictions must be modified. Indeed, it is found that in collisionless plasmas, the marginal stability condition for MHD modes is inherently incompressible for ion distribution functions that depend only on total energy. The absence of compressibility stabilization is then due to wave particle resonances. An illustration of the vanishing of plasma compressibility stabilization in closed line systems is given by studying the particular case of the hard-core Z-pinch.
by Antoine Julien Cerfon.
Ph.D.
6
Trophime, Christophe. "Modélisation numérique du couplage magnétohydrodynamique (MHD) fort : application à la propulsion MHD navale." Grenoble INPG, 1995. https://hal.archives-ouvertes.fr/tel-01340645.
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Nous présentons un code numérique 3D de simulation des phénomènes magnétohydrodynamiques. Le problème électromagnétique est traité par la méthode des éléments finis. Les équations de Navier-Stokes pour les fluides incompressibles en régime permanent sont résolues à l’aide de la méthode des Volumes Finis. Le couplage de ces deux méthodes est réalisé par des procédures d’interpolation pour le calcul des forces de Laplace et du champ de vitesse. Le code est appliqué à différents problèmes M. H. D. Ces exemples permettent de valider et de mettre en évidence les situations de couplage M. H. D. Traitées par notre programme. Enfin la modélisation de la propulsion navale M. H. D. Est abordée. Elle concerne à la fois les systèmes à conduction et à induction. Une attention particulière est portée au couplage entre l’écoulement et les forces électromagnétiques dans les deux casWe present a 3D numerical simulation code for MHD phenomena. The electromagnetic problem is treated by the finite element method. Navier-Stokes equations for incompressible fluid in steady state are solved using the Finite Volumes method. The coupling of these two methods is performed by interpolation procedures for calculating the Laplace forces and the velocity field. The code is applied to different MHD problems. These examples validate and highlight coupling MHD situations, processed by our program. Finally the modeling of naval MHD propulsion is discussed. It relates to both systems conduction and induction. Particular attention is paid to the coupling between flow and electromagnetic forces in both cases
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Gerbeth, Gunter, Willi Witke, Horst Langenbrunner, and Sven Eckert. "MHD Turbulence: Use of gas bubbles as local tracers in Liquid Metal MHD Flows." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32058.
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Gerbeth, Gunter, Willi Witke, Horst Langenbrunner, and Sven Eckert. "MHD Turbulence: Use of gas bubbles as local tracers in Liquid Metal MHD Flows." Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22032.
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Taylor, Matthew Graham George Thaddeus. "MHD modelling of space plasmas." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342232.
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Tam, Kuan V. "MHD simulations of coronal heating." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6373.
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The problem of heating the solar corona requires the conversion of magnetic energy into thermal energy. Presently, there are two promising mechanisms for heating the solar corona: wave heating and nanoflare heating. In this thesis, we consider nanoflare heating only. Previous modelling has shown that the kink instability can trigger energy release and heating in large scale loops, as the field rapidly relaxes to a lower energy state under the Taylor relaxation theory. Two distinct experiments were developed to understand the coronal heating problem: the avalanche effect within a multiple loop system, and the importance of thermal conduction and optically thin radiation during the evolution of the kinked-unstable coronal magnetic field. The first experiment showed that a kink-unstable thread can also destabilise nearby threads under some conditions. The second experiment showed that the inclusion of thermal conduction and optically thin radiation causes significant change to the internal energy of the coronal loop. After the initial instability occurs, there is continual heating throughout the relaxation process. Our simulation results show that the data is consistent with observation values, and the relaxation process can take over 200 seconds to reach the final relaxed state. The inclusion of both effects perhaps provides a more realistic and rapid heating experiment compared to previous investigations.
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Fernandes, Tiago. "Instabilidades MHD no Tokamak TCABR." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-03062016-155509/.
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Este trabalho descreve o estudo das instabilidades magneto-hidro-dinâmicas (MHD) comumente observadas nas descargas elétricas de plasma no tokamak TCABR, do Instituto de Física da USP. Dois diagnósticos principais foram empregados para observar essas instabilidades: um conjunto poloidal de 24 bobinas magnéticas (bobinas de Mirnov) colocadas próximas à borda do plasma e um medidor de emissões na faixa do Ultra Violeta e de raios X moles com 20 canais (sistema SXR), cujo circuito de condicionamento de sinais foi aprimorado como parte deste trabalho. Esses diagnósticos foram escolhidos porque fornecem informações complementares, uma vez que o sistema SXR observa a parte central da coluna de plasma, enquanto as bobinas de Mirnov detectam as instabilidades MHD na região mais externa da coluna. As informações coletadas por esses diagnósticos foram submetidas à análise espectral com resolução temporal e espacial, possibilitando determinar a evolução das características espectrais e espaciais das instabilidades MHD observadas. Essas análises revelaram que durante a etapa inicial da formação do plasma (quando a corrente de plasma ainda está aumentando) ilhas magnéticas com números de onda decrescente, identificadas como sendo modos kink de borda, são detectadas nas bobinas de Mirnov. Após a formação do plasma, quando os parâmetros de equilíbrio estão relativamente estáveis (platô), oscilações são detectadas tanto nas bobinas de Mirnov quanto no sistema de SXR, indicando a presença de instabilidades MHD em toda a coluna de plasma. Em geral as oscilações medidas nas bobinas de Mirnov tem baixa amplitude e correspondem a pequenas ilhas magnéticas que foram identificadas como sendo modos de ruptura (modos tearing). Por outro lado, as instabilidades na região central foram identificadas como dentes de serra, que correspondem a relaxações periódicas da região interna à superfície magnética com fator de segurança q=1 e que são acompanhadas de oscilações precursoras, cuja amplitude depende da fase do ciclo de relaxação. Devido à essa modulação de amplitude, aparecem picos de frequência satélite nos espectrogramas dos sinais do SXR. Além disso, devido ao fato dos ciclos de relaxação não serem sinusoidais, os harmônicos da frequência de relaxação também aparecem nesses espectrogramas. No entanto, em muitas descargas do TCABR, a intensidade das oscilações medidas nas bobinas de Mirnov aumentam significativamente durante o platô, com efeitos sobre a frequência de todas as instabilidades MHD, até mesmo sobre os dentes de serra localizados na região central da coluna. Em todos os casos, observou-se que durante o platô a frequência das ilhas magnéticas coincide com a frequência das oscilações precursoras do dente de serra, apesar de serem duas instabilidades distintas, localizadas em posições radiais muito diferentes. Essa coincidência de frequências possibilitou descrever a evolução em frequência de todas as oscilações detectadas em diversos diagnósticos com base em apenas duas frequências básicas: a dos ciclos de relaxação dente de serra e a das ilhas magnéticas.This work describes the study of magneto-hydro-dynamic instabilities (MHD) commonly observed in plasma discharges in tokamak TCABR (at Instituto de Física da USP). Two main diagnostics were employed to observe these instabilities: a poloidal set of 24 magnetic coils (Mirnov coils) placed near the plasma border and a detector of emissions in the Ultra Violet and soft X-ray range with 20 channels (SXR system) which improvement of the signal conditioning circuit was done as part of this work. These diagnostics were chosen because they provide complementary information, since the SXR system measures the central part of the plasma column, while the Mirnov coils detect the MHD instabilities in the outer part of the column. The information collected by these diagnoses was submitted to spectral analysis with temporal and spatial resolution, making it possible to determine the evolution of the spectral and spatial characteristics of the observed MHD instabilities. These analyzes revealed that during the initial stage of the plasma formation (when the plasma current is still increasing) magnetic islands with decreasing wave numbers, identified as edge kink modes, are detected in the Mirnov coils. After the plasma formation, when the equilibrium parameters are relatively flat (plateau), oscillations are detected in both Mirnov coils and SXR system, indicating the presence of MHD instability in the whole plasma column. In general, the fluctuations measured by the Mirnov coils have low amplitude corresponding to small magnetic islands, which were identified as tearing modes. On the other hand, the instabilities at the central region were identified as sawteeth oscillations that correspond to periodic relaxations in the internal region of the magnetic surface with safety factor q = 1 and that are accompanied by precursor oscillations which amplitude depends on the phase of the relaxation cycles. Due to this amplitude modulation, frequency satellite peaks appear in the spectrograms of the SXR signals. Furthermore, due to the fact that relaxation cycles are not sinusoidal, harmonics of the relaxation frequency also appear in the spectrograms. However, in many TCABR discharges, the intensity of the oscillations measured by the Mirnov coils increase significantly during the plateau, with affects the frequency of all MHD instabilities, even over the sawteeth in the central region of the column. In all cases, it was observed that during the plateau the frequency of the magnetic islands coincides with the frequency of the sawtooth precursors, although they are two different instabilities located in separated radial positions. This coincidence of frequencies allowed describing the frequency evolution of all measured oscillations by considering only two basic frequencies: the cycles of sawtooth relaxation and the magnetic islands.
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Barker, Bryn Nicole. "Stability of MHD Shock Waves." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8437.
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This thesis focuses on the study of spectral stability of planar shock waves in 2-dimensional magnetohydrodynamics. We begin with a numerical approach, computing the Lopatinski determinant and Evans function with the goal of determining if there are parameters for which viscous waves are unstable and the corresponding inviscid waves are stable. We also begin developing a method to obtain an explicit, analytical representation of the Evans function. We demonstrate the capabilities of this method with compressible Navier-Stokes and extend our results to 2-D MHD. Finally, using compressible Navier-Stokes again, we derive an energy estimate as a first step in improving the bound on possible roots of the Evans function.
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Tůma, Jan. "Mobilní asistent pro cestování MHD." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2017. http://www.nusl.cz/ntk/nusl-363875.
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This thesis is a documentation covering complete design and implementation of a mobile public transportation assistant for Brno. The resulting solution consists of a mobile application and a server part. The mobile application allow user with actual position of public transport vehicles and positon of smart device navigate and determine optimal route. The server part includes web service for client-server communication.
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Martinkovič, David. "Analýza MHD Prahy a Singapuru." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-3657.
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Práce se zabývá analýzou a srovnáním Městského hromadného systému v Praze a Singapuru. Ukazuje na problémy a jejich možné řešení použítím určitých specifických rysů srovnávaných systémů. Analýza se týká integrovaného systému, jízdného, dopravních prostředků a jejich provozu.
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Dostálová, Pavla. "MHD Olomouc v kontextu IDSOK." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-17043.
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The thesis deals with problem of urban mass transportation. Theoretical part is focused on mass transportation. The thesis contains delimination of area - Olomoucky Region - and its mass transportation - integrated transport system "IDSOK". The main part of the thesis deals with Urban Mass Transportation in Olomouc. There are analyzed selected problems of urban mass transportation as comfort, adherence to time tables, new tram traces routing - operating expenses of trams and buses - and communication with passengers.
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Siegerová, Lucie. "Srovnání MHD vybraných evropských měst." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-142237.
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The Diploma Thesis is focused on description of public transport systems in Prague, London and Vienna and their final comparison. Theoretical part is describing development of transport, means of transport, system of tariffs etc. In practical part both systems are detaily described and final comparision.
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Pontin, David. "The nature of 3D magnetic reconnection." Thesis, University of St Andrews, 2004. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723688.
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Carter, Ben. "MHD Modes in Structured Magnetic Waveguides." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486546.
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In this Thesis the theoretical aspects of MHD wave modes in structured magnetic fields are studied. In particular the complication of a simple magnetic tube to include a transitionallayer and also to include twist is investigated. Solar observations have shown that the magnetic field on the Sun is far from simple and that wave guides occur in a vast array of different structures. More recent interpretations of observations have also indicated at a sub-structure to magnetic flux tubes for which current instruments do not yet have the resolution to image directly. It is proposed that such a flux tube could contain a sub-structure modelled by a magnetic cylinder in the form ofa magnetic core and magnetic annulus. The dispersion relations are found for a purely straight configuration and also for the case when the magnetic field is twisted. The modes of oscillation are investigated with specific attention given to the effect ofthe additional layer and to that of the twist on the existing modes. It is found that the change iJ? geometry of the magnetic flux tube has a marked effect on both the existence and on the phase speed of different modes. The introduction of an annulus layer increases the number of surface modes that exist and an applied twist gives rise to an infinite set of body modes and also transforms the behaviour of the surface modes, now having a dual nature - body or surface depending on wavelength. Short and long wav'e1ength analytical solutions are· sought providing further insight into the role ofmagnetic structuring in a flux tube.
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Bohan, Matthew Tanguy. "MHD Models of Relativistic Magnetic Reconnection." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521444.
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Daum, Patrick. "Global MHD Simulation of Magnetospheric Phenomena." Thesis, Lancaster University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531686.
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King, Damian Bryan. "MHD waves in the solar corona." Thesis, University of Warwick, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443312.
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Homem, Miguel Stone de Terra. "Steady state MHD : waves and instabilities." Thesis, University of Sheffield, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408368.
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Pribyl, Patrick A. "Measured MHD equilibrium in Alcator C." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14881.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 204-206.
by Patrick A. Pribyl.
Ph.D.
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Wei, Xing. "Rotating MHD in a spherical shell." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611253.
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Pizur, Jaroslav. "Klasifikace linek MHD z GNSS dat." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442529.
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The subject of this thesis is digitalization of bus transportation. The input is represented by a sequence of GNSS data which are transformed to the OpenStreetMap format. Doing so, it is enriched by the information OpenStreetMap format provides and it gains its positional advantages as well. Then this thesis deals with ways by which one can detect bus lines from this general sequence of GNSS coordinates. A bus line is recognized as a repeating trajectory, which satisfies criteria derived from its expectable or defined characteristics. A few clustering solutions are proposed and tested for their performance. On the basis of this testing, there is one solution chosen as the best performing one, to be the proposed solution of this thesis. The overall output will therefore be formed by automatic mapping of bus lines with no theoretical area limit and with minimum manual intervention needed. It lays the foundations for various intelligent real-time processes to be implemented as well as allowing for infrastructure to be processed for the statistics purposes or urban planning.
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Nečas, František. "Projekt zavedení MHD v České Třebové." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-16468.
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Masters thesis creates project of public transport in Česká Třebová. Confronts the current situation in the city with its needs and taking account of the planned solution to the traffic situation creates new and better project.
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Kameníčková, Andrea. "Srovnání MHD v Praze a Sydney." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-125103.
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The Diploma Thesis is focused on description of public transport systems in Prague and Sydney and their final comparison. Theoretical part is describing development of transport, transport infrastructure, public transport priority, system of tariffs, means of transport etc. In practical part both systems are described in detail with focus on organization and functionality. Final comparison is focused on confrontation from many points of view to capture the most of identical or different aspects.
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Sato, Masahiko. "Nonlinear MHD Phenomena of Cylindrical Tokamaks." Kyoto University, 2003. http://hdl.handle.net/2433/148651.
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Kyoto University (京都大学)0048
新制・課程博士
博士(エネルギー科学)
甲第10333号
エネ博第69号
新制||エネ||20(附属図書館)
UT51-2003-H754
京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻
(主査)教授 前川 孝, 教授 近藤 克己, 助教授 浜口 智志
学位規則第4条第1項該当
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Udrea, Bogdan. "An advanced implicit solver for MHD /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/10003.
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Del, Zanna Luca. "MHD flows in the solar atmosphere." Thesis, University of St Andrews, 1997. http://hdl.handle.net/10023/14075.
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In this thesis, different aspects of the physics of flows in the solar atmosphere are examined. These are described by means of the set of (ideal) magnetohydrodynamics (MHD) and throughout the thesis there is a progressive refinement in the mathematical methods to solve these equations. First, an analysis of symmetric MHD equilibria is presented and the difficulties that are found in solving the steady equations, both analytically and numerically, are discussed in detail. A novel method to find exact solutions in the incompressible case is presented and families of solutions are given in different geometries. Then, attention is turned to flows in coronal magnetic structures, namely quiescent prominences (closed fieldlines) and polar plumes (open fieldlines), and MHD models for these structures are developed by following two different methods: for the former a semi- analytic approach while for the latter a linearisation through a low β assumption. In the prominence model, the effects of a subsonic flow along the fieldlines supporting the structure are studied and the results are compared both with a previous static model and with the observed flow speeds. For the plume model, flows are supposed to be transonic along the open fieldlines and their behaviour is studied for different distributions of temperature, density and magnetic flux. However, here the main goal is to demonstrate that coronal plumes are essentially magnetic features and some results of the model are compared with observations. Finally, a time dependent MHD code in spherical coordinates is presented. The aim is to study the interaction of the solar wind with the large scale coronal magnetic structures and the propagation of MHD waves. As a test in 1-D, simulations of the dynamic response of a spherically symmetric extended corona to changes at the outer pressure are studied, following a previous analytic work.
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Flint, Christopher Robert. "Computational Methods of Lattice Boltzmann Mhd." W&M ScholarWorks, 2017. https://scholarworks.wm.edu/etd/1530192360.
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Lattice Boltzmann (LB) Methods are a somewhat novel approach to Computational Fluid Dynamics (CFD) simulations. These methods simulate Navier-Stokes and magnetohydrodynamics (MHD) equations on the mesoscopic (quasi-kinetic) scale by solving for a statistical distribution of particles rather than attempting to solve the nonlinear macroscopic equations directly. These LB methods allow for a highly parallelizable code since one replaces the difficult nonlinear convective derivatives of MHD by simple linear advection on a lattice. New developments in LB have significantly extended the numerical stability limits of its applicability. These developments include multiple relaxation times (MRT) in the collision operators, maximizing entropy to ensure positive definiteness in the distribution functions, as well as large eddy simulations of MHD turbulence. Improving the limits of this highly parallelizable simulation method allows it to become an ideal candidate for simulating various fluid and plasma problems; improving both the speed of the simulation and the spatial grid resolution of the LB algorithms on today's high performance supercomputers. Some of these LB extensions are discussed and tested against various problems in magnetized plasmas.
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Straka, Radomír. "RFID identifikace zastávek MHD pro nevidomé." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219841.
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The aim of this master’s thesis is to design a device for identification of bus stops for blind people. In the beginning the work describes information about the RFID system, characterizes each part of this system, mutual communication of its components and evaluates possibilities of RFID communication frequency bands. Subsequently the work describes the block diagram of the device and the circuit scheme of each block. Work concentrates on a selection of circuit components for the RFID transceiver, the voice module, the control module and choose a suitable transponder to place it on metal constructions. Control programs are also described. PCB design of each board, partlists and source codes are in the appendices of this master’s thesis.
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Velsh, Marina. "Design městského mobiliáře pro zastávku MHD." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-255790.
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This work is dedicated to development of city furniture (station shed, bench, litter box). The first part contains the analysis of city furniture (historical, technical and design). Second part is dedicated to the design decision in particular. The main goal was to contemplate the design of station shed, which will be totally defending from bad weather; bench design, which would be impossible to be used as a ‘bed for homeless’; litter box, which would be aesthetically matching the shed and the bench. Additional task was to contemplate canopies of various sizes, enabling the city to install same type of canopies regardless of the size. The suggested design has been influenced by aesthetics, ergonomics, technology and other important aspects of industrial design.
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Olynyk, Geoffrey Michael. "Radiation asymmetry and MHD activity in rapid shutdowns on Alcator C-Mod." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/86421.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references.
Disruptions, the sudden termination of tokamak fusion plasmas by instabilities, have the potential to cause severe material wall damage to large tokamaks like ITER.e mitigation of disruption damage is an essential part of any fusion reactor system. Massive gas injection (MGI) rapid shutdown is a technique in which large amounts of noble gas are injected into the plasma in order to safely radiate the plasma energy evenly over the entire plasma-facing first wall. However, it has been observed that this energy is not radiated evenly: it can have significant asymmetries, which could cause melting in large devices even in the case of a successful rapid shutdown. The first rapid shutdown experiments using multiple gas injectors on any tokamak were conducted on Alcator C-Mod. A dedicated toroidal array of fast ultraviolet photodiodes was installed in order to diagnose toroidal radiation asymmetries during the thermal quench (TQ). It is found that the radiation asymmetry is controlled by a low-n brightness mode in the TQ phase of rapid shutdowns. is mode sometimes rotates, and the rate of rotation sets the integrated radiation asymmetry in the TQ. It is proposed that this brightness feature is caused by the transport of energy from the hot plasma core to the radiative edge by the MHD flow at one phase of an n = 1 global MHD mode. is phenomenology is confirmed by extended MHD simulation using the NIMROD code. An exponentially growing n = 1 magnetic mode is observed during the pre-TQ phase of MGI rapid shutdowns; the saturation of this mode marks the beginning of the thermal quench. It is proposed that this mode is a magnetic island caused by a radiative tearing mode; the predicted growth rate is compared to the predictions of analytic theory. It is proposed that this mode is a magnetic island then couples to other global n = 1 MHD modes, causing the energy transport during the TQ. An important implication of this result is that simply adding more gas injectors cannot guarantee a symmetric rapid shutdown: the asymmetry is controlled by the behavior of the core MHD activity during the TQ. the implications of this rotating radiation asymmetry during the TQ of MGI rapid shutdown for the beryllium wall of ITER are discussed.
by Geoffrey Michael Olynyk.
Ph. D.
35
Schmittdiel, D. (David) 1978. "Investigation of Alfvén eigenmodes in Alcator C-Mod using active MHD spectroscopy." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/17044.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 2003.Includes bibliographical references (119-121).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Alfvén eigenmodes that exist in the shear Alfvén continuum of toroidal magnetic fusion devices may be important for the confinement of energetic particles, particularly fusion-born alpha particles in burning plasma experiments. Interaction between these energetic particles and weakly damped toroidal Alfvén eigenmodes (TAE's) may cause anomalous particle transport leading to incomplete thermalization and possible first wall damage. These consequences must be avoided in next step burning plasma devices and thus an investigation into the stability of TAE's in present machines un- der reactor-like conditions is essential. Measurement of the damping rate of TAE's will provide insight into this area of research. The investigation of TAE's on Alcator C-Mod is accomplished by employing the recently completed Active MHD Spectroscopy system. Antennas mounted inside the C-Mod vacuum vessel are driven by a high power amplifier in the TAE range of frequencies and excite modes inside the plasma. Magnetic fluctuation diagnostics provide the plasma response to this excitation. The damping rate is then calculated from the complex transfer function between the antenna current and plasma response signals.
by David Anthony Schmittdiel.
S.M.
36
Kleimann, Jens. "MHD-Modellierung der Dynamik der solaren Korona." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976561352.
Full text
37
Stasyszyn, Federico Andrés. "MHD numerical simulations in a cosmological context." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-131385.
Full text
38
Mistrangelo, Chiara. "Three-dimensional MHD flow in sudden expansions." Karlsruhe : FZKA, 2005. http://bibliothek.fzk.de/zb/berichte/FZKA7201.pdf.
Full text
39
Clack, Christopher. "Nonlinear Resonant MHD Waves in Solar Plasmas." Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522061.
Full text
40
Giagkiozis, Ioannis. "Axisymmetric MHD modes in twisted magnetic fields." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/19956/.
Full textAbstract:
Vortex flows in the solar atmosphere may contribute significantly to the energy flux requirements for heating the quiet Sun atmosphere. This thesis presents evidence that the expected number of vortices in the solar photosphere is significantly larger than estimated and most importantly their lifetime is, in the mean, much shorter than previously believed. This suggests that vortex flows are highly dynamic and that their formation and dissolution is highly temporally localised. The measurements and statistics that support this evidence were made possible by use of an automated vortex identification approach which allowed for a much larger sample. In fact the number of identified vortices is several orders of magnitude larger compared with the latest research on the subject. Given that vortices in the solar photosphere can introduce magnetic twist, a pertinent question then is: "How would that magnetic twist affect axisymmetric MHD modes?". Part of this thesis visits this question and the theoretical models used offer interesting answers. Firstly, even for weak magnetic twist the long wavelength cut-off for the sausage mode that is present in models without magnetic twist, is removed! It is shown that magnetic twist naturally couples axisymmetric Alfven waves with sausage waves. A coupling that results, among other things, in sausage waves exhibiting Doppler signatures similar to these expected to be observed in Alfven waves. These modes can also be excited by a larger variety of drivers compared to the pure sausage and axisymmetric Alfven waves. Something that makes them more pertinent to the question of energy propagation than their pure cousins (sausage and Alfven waves). Lastly, a calculation is presented, for the first time, of a dispersion relation for resonantly damped axisymmetric modes, in the spectrum of the Alfven continuum and also an approximation is presented of the damping time in the long wavelength limit. It is shown that the damping times can be comparable to that observed for the kink mode in the case that there is no magnetic twist.
41
Chahine, Robert. "MHD simulations of the Reversed Field Pinch." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC056/document.
Full textAbstract:
La dynamique des plasmas de fusion par confinement magnétique dans la configuration Reversed Field Pinch (RFP) est ´étudiée en utilisant la description magnétohydrodynamique (MHD) incompressible. Une méthode pseudo-spectrale et une technique de pénalisation en volume sont utilisées pour résoudre le système d’équations dans un cylindre. Les simulations numériques montrent que la pression joue un rôle important dans la dynamique des RFP et ne peut pas être négligée. Ainsi, ß n’est plus le paramètre principal pour décrire la dynamique des RFPs mais plutôt ß’ ∇, un nouveau paramètre qui équivaut le rapport du module de gradient de pression et le module de la force de Lorentz. A un autre niveau, l’effet du changement de la section poloïdale du RFP sur la dynamique est étudié. Les simulations des écoulements RFP ayant le même nombre de Lundquist et des sections différentes (circulaire et elliptique), montrent une grande différence dans les spectres et la diffusion turbulente radiale. Finalement, les écoulements RFP sont utilisés pour étudier l’effet dynamo. Les résultats obtenus montrent que les écoulements RFP sont capables d’amplifier un champ magnétique passif qui aura une tendance à être plus non-linéaire que le champ magnétique du RFP dans les régimes turbulentsThe dynamics of magnetic fusion plasmas in the Reversed Field Pinch (RFP) configuration are studied using an incompressible magnetohydrodynamics (MHD) description. A pseudospectral method combined with a volume penalization method are used to resolve the governing equations in a straight cylinder. Numerical simulations show that the pressure effects on the RFP dynamics cannot be neglected, and thus the _ parameter is not adequate to characterize the importance of pressure in the dynamics. A new parameter, _0r , which is the ratio of the pressure gradient’s magnitude to the Lorentz force’s magnitude, is proposed to be the proper parameter to describe the RFP dynamics. Another investigated influence on the RFP dynamics is the shaping of the poloidal cross-section. Simulations of flows with the same Lundquist number and different cross-sections (circular and elliptic) show a clear change in the spectral behaviour, as well as in the radial turbulent diffusion. Finally, the RFP flows are used to study the dynamo effect. Numerical results show that RFP flows are capable of amplifying a seed magnetic field, which will have tendency to be more nonlinear than the RFP magnetic field in the turbulent regime
42
McCormick, David S. "Existence and uniqueness theory for MHD systems." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/66955/.
Full textAbstract:
This thesis establishes the existence and uniqueness of solutions to certain systems of equations connected to magnetohydrodynamics (MHD). The models have potential applications to the method of magnetic relaxation introduced by Moffatt (J. Fluid. Mech. 159, 359-378, 1985) to construct stationary Euler ows with non-trivial topology. Firstly, we prove existence, uniqueness and regularity of weak solutions of a coupled parabolic-elliptic model in 2D, and existence of weak solutions in 3D; we consider the standard equations of MHD with the advective terms removed from the velocity equation. Despite the apparent simplicity of the model, the proof in 2D requires results that are at the limit of what is available, including elliptic regularity in L1 and a strengthened form of the Ladyzhenskaya inequality ||f||L3≤c||f||1/2 L2,∞||∇f||1/2 L2 Secondly, we establish the local-in-time existence and uniqueness of strong solutions in Hs for s>n=2 to the viscous, non-resistive MHD equations in Rn, n = 2; 3, as well as for a related model where the advection terms are removed from the velocity equation (the above parabolic-elliptic system with zero resistivity). The uniform bounds required for proving existence are established by means of a new estimate, which is a partial generalisation of the commutator estimate of Kato & Ponce (Comm. Pure Appl. Math. 41(7), 891-907, 1988). Finally, we generalise the results of the previous chapter to prove the localin-time existence of strong solutions in the Besov space Bn/2 2;1 (ℝn) to the viscous, non-resistive MHD equations in ℝn.
43
Peyrou, Bruno. "Modélisation MHD d'un arc de foudroiement d'aéronef." Rouen, 2012. http://www.theses.fr/2012ROUES042.
Full textAbstract:
Cette thèse s'inscrit dans l'étude du foudroiement d'un aéronef que mène l'ONERA depuis plusieurs années. L'étude est centrée uniquement sur la modélisation de l'arc et son évolution lorsqu'une impulsion de courant intense le traverse. L'interaction de l'arc foudre avec la structure n'est pas étudiée à ce stade. L'arc est assimilé à un cylindre, cela permet de ramener le problème à une résolution des grandeurs physiques sur un rayon de l'arc. Le modèle est basé sur une modélisation magnétohydrodynamique qui comprend un modèle hydrodynamique, un modèle de transfert radiatif et un modèle pour l'électromagnétisme. Il est montré que le plasma dans ce type d'arc peut être considéré à l'équilibre thermodynamique local sauf au tout premier instant ou dans les zones très étroites en périphérie de l'arc. Le solveur CHARME de l'ONERA est utilisé pour résoudre les équations de la mécanique des fluides dans lesquelles sont pris en compte le terme source de quantité de mouvement lié à la force de Laplace et les termes sources d'énergie liés à l'effet Joule et au rayonnement. La résolution de l'équation de transfert radiatif est réalisée par l'approximation géométrique P1 couplée à une approximation spectrale sur les coefficients d'absorption qui sont nivelés sur 11 bandes fréquentielles par la moyenne de Rosseland. L'électromagnétisme est résolu dans l'approximation des régimes quasi statiques magnétiques. L'étude paramétrique montre que le rayonnement, au travers de l'absorption dans les zones périphériques de l'arc, est le mécanisme principal d'expansion du canal de l'arc. La force de Laplace augmente de plus du double la pression au coeur du canal lorsque les courants dépassent 100 kA. Les effets inductifs n'ont pas une incidence forte sur l'hydrodynamique du canal. Au niveau aéronautique, ce modèle montre que : - un foudroiement au sol est majorant par rapport à un en altitude, - la forme d'onde de courant A génère des arcs représentatifs de la foudre, - l'effet Joule et la pression dans l'arc évoluent respectivement de façon quadratique et non linéaire avec le courantThis work concerns the study of an electric arc of the lightning strike of an aircraft during current pulse. The study is narrowed to a one dimensional geometry, without interaction between the arc and the fuselage of the aircraft. The magnetohydrodynamic model is based on the hypothesis of a plasma at local thermal equilibrium, of a compressible fluid and of a quasi static electromagnetic field. The study is composed of two main parts. In a first step the hypothesis of the model are studied; their influence on the dynamic of the channel of the arc is enlightened. It is shown that the modeling of the arc during a current pulse has to take into account the Laplace force, the Neumann induction in order to simulate the inductive effects, the whole radiative transfer (emission and absorption); the Lorentz induction can be neglected. The second part treats of the evolution of the arc during the current pulse in several configurations. In this part, the effects of the altitude on the expansion of the arc are studied; it is shown that the higher the aircraft is struck, the less powerful the thermal and mechanic constraint is. The non linear growth of the constraint (Joule effect and pressure) on the material with the increase of maximum current is also shown. Then, current waves of different types are studied and we show that the constraints are really close for the same currrent level whatever the form of the current wave. Finally, the study of a current impulse taking place after a continuous current lightning arc is led. From it, we show that the constraint on the fuselage is weaker in this configuration, both because of the quicker growth of the channel radius and the weaker pressure
44
Kargina, Elena. "Porovnání MHD v Moskvě a v Praze." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-75506.
Full textAbstract:
The paper deals with the description and analysis of public transport in major cities of the Russian Federation and the Czech Republic - Prague and Moscow. Attention is devoted mainly to the state, plans and prospects of development, investment and crime. Very interesting part is the history of public transportation in both cities. Based on the information gathered, the adequacy of public transport for both cities, the size of transport companies, financing of public transport have been evaluated. Chapter plans and prospects informes about the planned construction of new metro lines in Prague and Moscow, which will help to improve infrastructure in the suburban areas of mentioned cities.
45
Štambergová, Kristina. "Srovnání MHD v Praze a San Franciscu." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-125096.
Full textAbstract:
The theorethical part contains a description of city public transit, its importance and history, priorities used in city public transit, tariff system, integrated transport systems and vehicles used in city public transit. The public transit systems in both cities are introduced and compared from several points of view in the practical part. The cities compared are Prague and San Francisco.
46
Fiala, Michal. "Terminál pro testování datových přenosů vozidel MHD." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220911.
Full textAbstract:
This term paper deals with subject of wireless communication of city rail transport cars. In this paper are described individual modules for transmission and receiving of data containing communication between city rail transport cars and measures of siding switches. Then there are discussed possibilities of design of system for testing functionality of transmitting and receiving modules and the system is consequently designed. There are also described communication principles and protocol used for wireless communication and MODBUS protocol used for communication over RS-485 serial line. In the end was the system manufactured, completed and equipped with necessary software.
47
Neretti, Gabriele <1980>. "Diagnostic techniques for EHD and MHD interaction." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1796/1/Neretti_Gabriele_tesi.pdf.
Full textAbstract:
The impact of plasma technologies is growing both in the academic and in the industrial fields. Nowadays, a great interest is focused in plasma applications
in aeronautics and astronautics domains.
Plasma actuators based on the Magneto-Hydro-Dynamic (MHD) and Electro-
Hydro-Dynamic (EHD) interactions are potentially able to suitably modify
the fluid-dynamics characteristics around a flying body without utilizing
moving parts. This could lead to the control of an aircraft with negligible
response time, more reliability and improvements of the performance. In
order to study the aforementioned interactions, a series of experiments and
a wide number of diagnostic techniques have been utilized.
The EHD interaction, realized by means of a Dielectric Barrier Discharge
(DBD) actuator, and its impact on the boundary layer have been evaluated
by means of two different experiments.
In the first one a three phase multi-electrode flat panel actuator is used. Different
external flow velocities (from 1 to 20m/s) and different values of the
supplied voltage and frequency have been considered. Moreover a change of
the phase sequence has been done to verify the influence of the electric field
existing between successive phases.
Measurements of the induced speed had shown the effect of the supply voltage
and the frequency, and the phase order in the momentum transfer phenomenon.
Gains in velocity, inside the boundary layer, of about 5m/s have
been obtained. Spectroscopic measurements allowed to determine the rotational
and the vibrational temperature of the plasma which lie in the range
of 320 ÷ 440°K and of 3000 ÷ 3900°K respectively. A deviation from thermodynamic
equilibrium had been found.
The second EHD experiment is realized on a single electrode pair DBD actuator
driven by nano-pulses superimposed to a DC or an AC bias. This
new supply system separates the plasma formation mechanism from the acceleration
action on the fluid, leading to an higher degree of the control of
the process. Both the voltage and the frequency of the nano-pulses and the
amplitude and the waveform of the bias have been varied during the experiment.
Plasma jets and vortex behavior had been observed by means of fast Schlieren
imaging. This allowed a deeper understanding of the EHD interaction process.
A velocity increase in the boundary layer of about 2m/s had been
measured.
Thrust measurements have been performed by means of a scales and compared
with experimental data reported in the literature. For similar voltage
amplitudes thrust larger than those of the literature, had been observed.
Surface charge measurements led to realize a modified DBD actuator able to obtain similar performances when compared with that of other experiments.
However in this case a DC bias replacing the AC bias had been used.
MHD interaction experiments had been carried out in a hypersonic wind
tunnel in argon with a flow of Mach 6. Before the MHD experiments a
thermal, fluid-dynamic and plasma characterization of the hypersonic argon
plasma flow have been done.
The electron temperature and the electron number density had been determined
by means of emission spectroscopy and microwave absorption measurements.
A deviation from thermodynamic equilibrium had been observed.
The electron number density showed to be frozen at the stagnation region
condition in the expansion through the nozzle.
MHD experiments have been performed using two axial symmetric test bodies.
Similar magnetic configurations were used. Permanent magnets inserted
into the test body allowed to generate inside the plasma azimuthal currents
around the conical shape of the body. These Faraday currents are responsible
of the MHD body force which acts against the flow.
The MHD interaction process has been observed by means of fast imaging,
pressure and electrical measurements. Images showed bright rings due to the
Faraday currents heating and exciting the plasma particles.
Pressure measurements showed increases of the pressure in the regions where
the MHD interaction is large. The pressure is 10 to 15% larger than when
the MHD interaction process is silent.
Finally by means of electrostatic probes mounted flush on the test body lateral
surface Hall fields of about 500V/m had been measured. These results
have been used for the validation of a numerical MHD code.
48
Neretti, Gabriele <1980>. "Diagnostic techniques for EHD and MHD interaction." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1796/.
Full textAbstract:
The impact of plasma technologies is growing both in the academic and in the industrial fields. Nowadays, a great interest is focused in plasma applications
in aeronautics and astronautics domains.
Plasma actuators based on the Magneto-Hydro-Dynamic (MHD) and Electro-
Hydro-Dynamic (EHD) interactions are potentially able to suitably modify
the fluid-dynamics characteristics around a flying body without utilizing
moving parts. This could lead to the control of an aircraft with negligible
response time, more reliability and improvements of the performance. In
order to study the aforementioned interactions, a series of experiments and
a wide number of diagnostic techniques have been utilized.
The EHD interaction, realized by means of a Dielectric Barrier Discharge
(DBD) actuator, and its impact on the boundary layer have been evaluated
by means of two different experiments.
In the first one a three phase multi-electrode flat panel actuator is used. Different
external flow velocities (from 1 to 20m/s) and different values of the
supplied voltage and frequency have been considered. Moreover a change of
the phase sequence has been done to verify the influence of the electric field
existing between successive phases.
Measurements of the induced speed had shown the effect of the supply voltage
and the frequency, and the phase order in the momentum transfer phenomenon.
Gains in velocity, inside the boundary layer, of about 5m/s have
been obtained. Spectroscopic measurements allowed to determine the rotational
and the vibrational temperature of the plasma which lie in the range
of 320 ÷ 440°K and of 3000 ÷ 3900°K respectively. A deviation from thermodynamic
equilibrium had been found.
The second EHD experiment is realized on a single electrode pair DBD actuator
driven by nano-pulses superimposed to a DC or an AC bias. This
new supply system separates the plasma formation mechanism from the acceleration
action on the fluid, leading to an higher degree of the control of
the process. Both the voltage and the frequency of the nano-pulses and the
amplitude and the waveform of the bias have been varied during the experiment.
Plasma jets and vortex behavior had been observed by means of fast Schlieren
imaging. This allowed a deeper understanding of the EHD interaction process.
A velocity increase in the boundary layer of about 2m/s had been
measured.
Thrust measurements have been performed by means of a scales and compared
with experimental data reported in the literature. For similar voltage
amplitudes thrust larger than those of the literature, had been observed.
Surface charge measurements led to realize a modified DBD actuator able to obtain similar performances when compared with that of other experiments.
However in this case a DC bias replacing the AC bias had been used.
MHD interaction experiments had been carried out in a hypersonic wind
tunnel in argon with a flow of Mach 6. Before the MHD experiments a
thermal, fluid-dynamic and plasma characterization of the hypersonic argon
plasma flow have been done.
The electron temperature and the electron number density had been determined
by means of emission spectroscopy and microwave absorption measurements.
A deviation from thermodynamic equilibrium had been observed.
The electron number density showed to be frozen at the stagnation region
condition in the expansion through the nozzle.
MHD experiments have been performed using two axial symmetric test bodies.
Similar magnetic configurations were used. Permanent magnets inserted
into the test body allowed to generate inside the plasma azimuthal currents
around the conical shape of the body. These Faraday currents are responsible
of the MHD body force which acts against the flow.
The MHD interaction process has been observed by means of fast imaging,
pressure and electrical measurements. Images showed bright rings due to the
Faraday currents heating and exciting the plasma particles.
Pressure measurements showed increases of the pressure in the regions where
the MHD interaction is large. The pressure is 10 to 15% larger than when
the MHD interaction process is silent.
Finally by means of electrostatic probes mounted flush on the test body lateral
surface Hall fields of about 500V/m had been measured. These results
have been used for the validation of a numerical MHD code.
49
Granciu, Veronica Maria <1982>. "Diagnostic Techniques for MHD in Hypersonic Flows." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2312/1/Granciu_Veronica_Maria_Tesi.pdf.
Full text
50
Granciu, Veronica Maria <1982>. "Diagnostic Techniques for MHD in Hypersonic Flows." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2312/.
Full text