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Espaços Vetoriais TopológicosCavalcante, Wasthenny Vasconcelos 27 February 2015 (has links)
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Previous issue date: 2015-02-27 / In this work we investigate the concept of topological vector spaces and their properties.
In the rst chapter we present two sections of basic results and in the other
sections we present a more general study of such spaces. In the second chapter we
restrict ourselves to the real scalar eld and we study, in the context of locally convex
spaces, the Hahn-Banach and Banach-Alaoglu theorems. We also build the weak,
weak-star, of bounded convergence and of pointwise convergence topologies. Finally
we investigate the Theorem of Banach-Steinhauss, the Open Mapping Theorem and
the Closed Graph Theorem. / Neste trabalho, estudamos o conceito de espa cos vetoriais topol ogicos e suas propriedades.
No primeiro cap tulo, apresentamos duas se c~oes de resultados b asicos e,
nas demais se c~oes, apresentamos um estudo sobre tais espa cos de forma mais ampla.
No segundo cap tulo, restringimo-nos ao corpo dos reais e fazemos um estudo sobre
os espa cos localmente convexos, o Teorema de Hahn-Banach, o Teorema de Banach-
Alaoglu, constru mos as topologias fraca, fraca-estrela, da converg^encia limitada e da
converg^encia pontual. Por ultimo, estudamos o Teorema da Limita c~ao Uniforme, o Teorema
do Gr a co Fechado e o da Aplica c~ao Aberta no contexto mais geral dos espa cos
de Fr echet.
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Design of Inductive Power Transmission System for Low Power Application with Movable Receiver and Large Air GapKallel, Bilel 09 April 2019 (has links)
Inductive power transmission is very useful, not only for systems where energy transfer should take place in hazardous, humid and wet areas, but also for mobile and very small systems. It finds today a widespread use in several fields, such as industry, automotive, medicine and smart buildings. For a good efficiency and a high-power transmission, the sending and the receiving coils should be perfectly aligned and close to each other. A misalignment between the sender and the receiver becomes unavoidable especially for systems with movable parts.
This thesis aims to improve the transmitted power, the mutual inductance, the power at the load, and consequently the power transmission efficiency in case of lateral misalignment between the sending and receiving coils and at large coil-to-coil distance. For this purpose, we adopt a multi input single output (MISO) coil system able to orientate the issued magnetic field to the receiving coil by powering the neighbouring sending coils of the active ones with a weak current in the opposite direction. Furthermore, an analytical model of the used coils and an accurate three-dimensional model of the system have been developed to calculate the induced voltage, the induced current, and the equivalent mutual inductance. Both simulation and experimental results prove that the proposed multi-coil inductive system having an hexagonal arrangement and the sending coils, which have the half diameter of the receiving coil, is able to improve significantly the transmitted power in case of lateral misalignment and big air gap. The novel MISO system reaches better efficiency beginning with an air gap of 50% of the sending coil diameter, and a misalignment of 28% of the sending coil diameter. It reaches the double of the transmitted power of the conventional two-coil inductive system at 50 mm air gap (corresponding to 166% of the sending coil diameter) and at 10 mm lateral misalignment (corresponding to 33% of the sending coil diameter).
In order to improve the equivalent mutual inductance between the primary and secondary sides and to avoid energy losses, we propose a receiver detection method using the sending coils themselves as detectors. Thereby, only the sending coils, under the receiver, are activated and the others remain switched off. For that, the peak of the AC current of the sending coils, is measured and then compared to a detection threshold. The excitation strategy of the active sending coils is optimized corresponding to the receiving coil position. The novel excitation strategy increases the mutual inductance by 85% and the induced voltage by 13% at perfect alignment and by 30% and 10% respectively at 10 mm lateral misalignment, in comparison to the MISO system without a receiver detector and coil-excitation strategy.
In order to increase the transmitted power by resonance, different system topologies have been investigated, such as series-series SS, series-parallel SP, parallel-series PS, and parallel-parallel PP topologies for different levels of load impedance. The results show that a multi-coil inductive system with parallel-parallel PP topology realizes a higher transmitted power than the other topologies for both high and low load impedance values.
The proposed multi-coil inductive system is suitable for low-power systems, such as wireless sensors and biomedical implants, but can be also applied to higher range of power at a flexible position of the receiver. / Die induktive Energieübertragung ist interessant, nicht nur für Systeme, bei denen die Energieübertragung in rauen, feuchten und nassen Bereichen erfolgen soll, sondern auch für mobile und sehr kleine Systeme. Diese Art von Energieübertragung findet heute eine breite Anwendung in verschiedenen Bereichen, wie z.B. Industrie, Automobil, Medizin und intelligente Gebäude. Um
eine gute Effizienz und eine hohe Energieübertragungsleistung zu realisieren, sollten die Sende- und Empfangsspulen perfekt ausgerichtet und nahe beieinander sein. Insbesondere bei Systemen mit beweglichen Teilen ist jedoch eine Fehlausrichtung zwischen Sender und Empfänger unvermeidlich.
Diese Arbeit zielt darauf ab, die übertragene Leistung, die gegenseitige Induktivität, die Leistung an der Last und damit den Wirkungsgrad der Leistungsübertragung im Falle einer seitlichen Fehlausrichtung zwischen Sende- und Empfangsspule und bei großem Abstand von Spule zu Spule zu verbessern. Zu diesem Zweck wird ein Multi-Input Single-Output (MISO)-Spulensystem vorgeschlagen, das in der Lage ist, das ausgegebene Magnetfeld auf die Empfangsspule auszurichten, indem die benachbarten Spulen der aktiven Sendespulen mit einem schwachen Strom in der entgegengesetzten Richtung versorgt wird. Darüber hinaus wurde ein analytisches Modell für die verwendeten Spulen und ein genaues dreidimensionales Modell für das System entwickelt, um die induzierte Spannung, den induzierten Strom und die äquivalente gegenseitige Induktivität zu berechnen. Sowohl die Simulation als auch die experimentellen Ergebnisse belegen, dass das vorgeschlagene induktive Mehrfachspulensystem mit hexagonaler Anordnung und die Sendespulen, die den halben Durchmesser der Empfangsspule haben, in der Lage sind, die Sendeleistung bei lateraler Fehlausrichtung und großem Luftspalt deutlich zu verbessern. Das neuartige MISO-System erreicht einen besseren Wirkungsgrad, beginnend mit einem Luftspalt von 50% des Sendespulendurchmessers und einer Fehlausrichtung von 28% des Sendespulendurchmessers. Sie erreicht bei 50 mm Luftspalt (entspricht 166% des Sendespulendurchmessers) und bei 10 mm seitlichem Versatz (entspricht 33% des Sendespulendurchmessers) das Doppelte der Sendeleistung des herkömmlichen Zwei-Spulen-Induktivsystems.
Um die äquivalente gegenseitige Induktivität zwischen Primär- und Sekundärseite zu verbessern und Energieverluste zu vermeiden, schlagen wir ein Verfahren zur Detektion des Empfängers vor, bei dem die Sendespulen selbst als Detektoren verwendet werden. Dabei werden nur die Sendespulen unter dem Empfänger aktiviert und die anderen bleiben ausgeschaltet. Dazu wird der Scheitelwert des Wechselstroms der Sendespulen gemessen und mit einem vorgegebenem Schwellenwert verglichen. Die Anregungsstrategie der aktiven Spulen wird entsprechend der Position der Empfangsspule optimiert. Die neuartige Anregungsstrategie erhöht die gegenseitige Induktivität um 85% und die induzierte Spannung um 13% bei perfekter Ausrichtung und um 30% bzw. 10% bei 10 mm seitlichem Versatz, im Vergleich zum MISO-System ohne Empfängerdetektor und Spulenanregungsstrategie.
Um die übertragene Leistung durch Resonanz zu erhöhen, wurden verschiedene Systemtopologien untersucht, wie z.B. Serien-SS, Serien-Parallel-SP, Parallel-Series-PS und Parallel-Parallel-PP-Topologien für verschiedene Stufen der Lastimpedanz. Die Ergebnisse zeigen, dass ein MISO System mit parallel-paralleler PP-Topologie eine höhere Sendeleistung realisiert als die anderen Topologien für hohe und niedrige Last-Impedanzen.
Das vorgeschlagene induktive Mehrspulensystem eignet sich für Systeme mit geringer Leistung, wie drahtlose Sensoren und biomedizinische Implantate, kann aber auch flexibler Position des Empfängers in einen höheren Leistungsbereich angewendet werden.
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Compact Multi-Coil Inductive Power Transfer System with a Dynamic Receiver Position EstimationBouattour, Ghada 07 April 2022 (has links)
Inductive power transfer (IPT) systems with tolerance to the lateral misalignment are
advantageous for enhancing the transmitted power, usability and security of the system. In this
thesis, a misalignment tolerant multi-coil design is proposed to supply stationary and dynamic
battery-free wireless devices. A compact architecture composed of individually switchable 3
layers of printed coils arranged with overlap for excellent surface coverage. A hybrid architecture
based on three compact AC supply modules reduces the supply circuit complexity on the sending
Seite 2 von 4side. It detects the position of the receiver coil quickly, controls the activation of the transmitting
coils and estimates the next receiver position. The proposed architecture reduces the circuit
footprint by a factor of 62% compared to common architectures.
A transmitter coil activation strategy is proposed based on the detection of the transmitting coils
voltage and communication between sending side and receiving side to detect devices to supply
nature and position and to differentiate them from other conductive objects in the sending area
to the supplying security. The experimental results prove that the proposed architecture has a
good performance for different trajectories when the device speed does not exceed 15 mm/s.
Besides, the maximum detection time for the initial device position is about 1.6 s. The maximal
time interval to check the transmitter coils is around 0.7 s.:1. INTRODUCTION
2. THEORETICAL BACKGROUND
3. STATE OF THE ART OF MULTI-COIL IPT SYSTEMS
4. NOVEL DESIGN OF A MULTI-COIL IPT SYSTEM
5. MULTI-COIL ACTIVATION PROCEDURE
6. EXPERIMENTAL INVESTIGATIONS
7. CONCLUSION AND OUTLOOK / Induktive Energieübertragungssysteme (IPT) mit Toleranz gegenüber seitlichem Versatz sind
vorteilhaft, um die übertragene Leistung, die Nutzbarkeit und die Sicherheit des Systems zu
verbessern. In dieser Arbeit wird ein versatztolerantes Multispulen-Design vorgeschlagen, um
stationäre und dynamische batterielose drahtlose Geräte zu versorgen. Die kompakte Architektur
besteht aus 3 einzeln schaltbaren Schichten gedruckter Spulen, die überlappend angeordnet sind,
um eine hervorragende Oberflächenabdeckung zu gewährleisten. Eine hybride Architektur, die auf
drei kompakten AC-Versorgungsmodulen basiert, reduziert die Komplexität der
Versorgungsschaltung auf der Senderseite. Sie erkennt die Position der Empfängerspule schnell,
steuert die Aktivierung der Sendespulen und schätzt die nächste Empfängerposition. Die
vorgeschlagene Architektur reduziert den Platzbedarf der Schaltung um einen Faktor von 62 % im
Vergleich zu herkömmlichen Architekturen.
Es wird eine Aktivierungsstrategie für die Sendespulen vorgeschlagen, die auf der Erkennung der
Spannung der Sendespulen und der Kommunikation zwischen Sende- und Empfangsseite basiert,
um die Art und Position der zu versorgenden Geräte zu erkennen und sie von anderen leitfähigen
Objekten im Sendebereich zu unterscheiden. Die experimentellen Ergebnisse zeigen, dass die
vorgeschlagene Architektur eine gute Leistung für verschiedene Trajektorien hat, wenn die
Geschwindigkeit der Geräte 15 mm/s nicht überschreitet. Außerdem beträgt die maximale
Erkennungszeit für die anfängliche Geräteposition etwa 1,6 s. Das maximale Zeitintervall für die
Überprüfung der Senderspulen beträgt etwa 0,7 s.:1. INTRODUCTION
2. THEORETICAL BACKGROUND
3. STATE OF THE ART OF MULTI-COIL IPT SYSTEMS
4. NOVEL DESIGN OF A MULTI-COIL IPT SYSTEM
5. MULTI-COIL ACTIVATION PROCEDURE
6. EXPERIMENTAL INVESTIGATIONS
7. CONCLUSION AND OUTLOOK
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Characterization of Additive Manufacturing Constraints for Bio-Inspired, Graph-Based Topology OptimizationPalmer, Asa Edward Easton January 2021 (has links)
No description available.
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Cohomologies on sympletic quotients of locally Euclidean Frolicher spacesTshilombo, Mukinayi Hermenegilde 08 1900 (has links)
This thesis deals with cohomologies on the symplectic quotient of a Frölicher space which is locally diffeomorphic to a Euclidean Frölicher subspace of Rn of constant dimension equal to n. The symplectic reduction under consideration in this thesis is an extension of the
Marsden-Weinstein quotient (also called, the reduced space) well-known from the finite-dimensional smooth manifold case. That is, starting with a proper and free action of a Frölicher-Lie-group on a locally Euclidean Frölicher space of finite constant dimension, we
study the smooth structure and the topology induced on a small subspace of the orbit space. It is on this topological space that we will construct selected cohomologies such as : sheaf cohomology, Alexander-Spanier cohomology, singular cohomology, ~Cech cohomology and de Rham cohomology. Some natural questions that will be investigated are for instance: the impact of the symplectic structure on these di erent cohomologies; the cohomology that will
give a good description of the topology on the objects of category of Frölicher spaces; the extension of the de Rham cohomology theorem in order to establish an isomorphism between the five cohomologies.
Beside the algebraic, topological and geometric study of these new objects, the thesis contains a modern formalism of Hamiltonian mechanics on the reduced space under symplectic and Poisson structures. / Mathematical Sciences / D. Phil. (Mathematics)
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Cohomologies on sympletic quotients of locally Euclidean Frolicher spacesTshilombo, Mukinayi Hermenegilde 08 1900 (has links)
This thesis deals with cohomologies on the symplectic quotient of a Frölicher space which is locally diffeomorphic to a Euclidean Frölicher subspace of Rn of constant dimension equal to n. The symplectic reduction under consideration in this thesis is an extension of the
Marsden-Weinstein quotient (also called, the reduced space) well-known from the finite-dimensional smooth manifold case. That is, starting with a proper and free action of a Frölicher-Lie-group on a locally Euclidean Frölicher space of finite constant dimension, we
study the smooth structure and the topology induced on a small subspace of the orbit space. It is on this topological space that we will construct selected cohomologies such as : sheaf cohomology, Alexander-Spanier cohomology, singular cohomology, ~Cech cohomology and de Rham cohomology. Some natural questions that will be investigated are for instance: the impact of the symplectic structure on these di erent cohomologies; the cohomology that will
give a good description of the topology on the objects of category of Frölicher spaces; the extension of the de Rham cohomology theorem in order to establish an isomorphism between the five cohomologies.
Beside the algebraic, topological and geometric study of these new objects, the thesis contains a modern formalism of Hamiltonian mechanics on the reduced space under symplectic and Poisson structures. / Mathematical Sciences / D. Phil. (Mathematics)
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A non-conventional multilevel flying-capacitor converter topologyGulpinar, Feyzullah January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This research proposes state-of-the-art multilevel converter topologies and their
modulation strategies, the implementation of a conventional flying-capacitor converter
topology up to four-level, and a new four-level flying-capacitor H-Bridge converter
confi guration. The three phase version of this proposed four-level flying-capacitor
H-Bridge converter is given as well in this study. The highlighted advantages of the
proposed converter are as following: (1) the same blocking voltage for all switches
employed in the con figuration, (2) no capacitor midpoint connection is needed, (3)
reduced number of passive elements as compared to the conventional solution, (4)
reduced total dc source value by comparison with the conventional topology.
The proposed four-level capacitor-clamped H-Bridge converter can be utilized as
a multilevel inverter application in an electri fied railway system, or in hybrid electric
vehicles.
In addition to the implementation of the proposed topology in this research, its
experimental setup has been designed to validate the simulation results of the given
converter topologies.
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