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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The City, The Girls, The Composer…The Phenomenon: Influences on the Performance of Vivaldi’s Bassoon Concertos at The Ospedale della Pietà

Duda, Cynthia M. 05 October 2009 (has links)
No description available.
22

Noch mehr Vivaldi: Ein Bericht

Delius, Nikolaus 18 October 2007 (has links)
Quellenforschung an Musikhandschriften der SLUB ist immer ein Erlebnis. Auch auf scheinbar ausgetretenen Pfaden ist mit Überraschungen zu rechnen ...
23

Vivaldi entdecken: Ein Fund und seine Vorgeschichte

Stockigt, Janice B. 06 October 2006 (has links)
Wie erwähnt (SLUB-Kurier 2005/4), hat die Musikhistorikerin Dr. Janice B. Stockigt, Mitglied der Australian Academy of the Humanities und der Faculty of Music der University of Melbourne (Kurzporträt in SLUB-Kurier 2001/4), letztes Jahr im historischen Musikalienbestand der SLUB den wohl wichtigsten Vivaldi-Fund seit 75 Jahren gemacht. Im Folgenden informiert Jan Stockigt selber über die Genese ihrer Entdeckung. Im März 2006 war der Bericht ertmals in Symposium The Newsletter of the Australian Academy of the Humantities erschienen. Die Übersetzung aus dem Englischen fertigte K.W. Geck an.
24

Das Glück des Geduldigen

Talbot, Michael 23 March 2012 (has links) (PDF)
Es ist fast eine Binsenweisheit, dass die besten Entdeckungen die am wenigsten erwarteten sind. Sie sind nämlich eher Nebenprodukt als eigentliches Ziel. Das Aufkommen elektronischer Datenbanken hat die Wahrscheinlichkeit immens vervielfacht, dass jemand, der die Zeit und Geduld hat, eine Weile vor einem Computerbildschirm zu sitzen, solche zufälligen Entdeckungen macht. Die in Kooperation mit der Bayerischen Staatsbibliothek München und der Staatsbibliothek zu Berlin – Preußischer Kulturbesitz – betriebene Datenbank von RISM (der Internationalen Organisation für die Beschreibung und den zentralen Nachweis von Musikquellen) hat kürzlich ein zusätzliches Rechercheinstrument erhalten – eine Incipitsuche. Dieses unglaublich starke und nutzerfreundliche Hilfsmittel ermöglicht es, durch Eingabe einer kurzen Buchstabenfolge, die für die Anfangsnoten einer Komposition steht, in Sekundenschnelle herauszufinden, ob zu einem Werk ein „Zwilling“ vorhanden ist – zugeordnet entweder demselben, einem anderen oder gar keinem Komponisten.
25

Algoritmus Vivaldi pro nalezení pozice stanice v Internetu / Vivaldi algorithm for Internet nodes localization

Handl, Tomáš January 2009 (has links)
Diploma thesis deals with usage of artificial coordinate systems used for localization of a station on the internet and prediction of delay between the stations. There are described and compared basic properties of centralized and decentralized algorithms providing station localization on the internet and RTT prediction. More in depth are presented main representatives of both types of algorithms such as GNP, IDMAPS or Lighthouse. Central part of thesis is aimed at getting to know Vivaldi distributed algorithm. Basic principle of the algorithm for constant and variable time step, using two dimensional coordinate system with 3rd parameter height, is here outlined. Further more implementation of this algorithm as a library Vivaldi-lib in the environment of Java is implemented. Part of the thesis are simulations of behaviour of this algorithm for both variations realized on artificial networks and data obtained from PlanetLab experimental network, using simulation created program VIVALDIMONITOR.
26

Das Glück des Geduldigen: Neues Licht auf zwei Vivaldi-Manuskripte in der SLUB

Talbot, Michael 23 March 2012 (has links)
Es ist fast eine Binsenweisheit, dass die besten Entdeckungen die am wenigsten erwarteten sind. Sie sind nämlich eher Nebenprodukt als eigentliches Ziel. Das Aufkommen elektronischer Datenbanken hat die Wahrscheinlichkeit immens vervielfacht, dass jemand, der die Zeit und Geduld hat, eine Weile vor einem Computerbildschirm zu sitzen, solche zufälligen Entdeckungen macht. Die in Kooperation mit der Bayerischen Staatsbibliothek München und der Staatsbibliothek zu Berlin – Preußischer Kulturbesitz – betriebene Datenbank von RISM (der Internationalen Organisation für die Beschreibung und den zentralen Nachweis von Musikquellen) hat kürzlich ein zusätzliches Rechercheinstrument erhalten – eine Incipitsuche. Dieses unglaublich starke und nutzerfreundliche Hilfsmittel ermöglicht es, durch Eingabe einer kurzen Buchstabenfolge, die für die Anfangsnoten einer Komposition steht, in Sekundenschnelle herauszufinden, ob zu einem Werk ein „Zwilling“ vorhanden ist – zugeordnet entweder demselben, einem anderen oder gar keinem Komponisten.
27

Dual-polarized fully-metallic Vivaldi antenna array in a triangular lattice / Dubbelpolariserad helmetallisk Vivaldi-antennuppsättning i ett triangulärt gitter

Orgeira Alvarez, Omar January 2022 (has links)
New mobile communication generations need electromagnetic sensors capable of steering their high-directive beams towards the users. Conventional base stations use square lattice phased arrays to accomplish this task. These arrays are composed of a large number of radiating elements to achieve the required high directivity and scanning capabilities. These systems are of high complexity and cost because after each element there is a large electronic chain. Therefore, it is of high interest to reduce the element count in the aperture of the array while maintaining its performance. Instead of using a square lattice to place the radiating elements, a triangular lattice can be used. It is proven that a triangular lattice optimally samples the aperture and reduces the element count by up to a 15.5%, hence reducing the cost and complexity of the complete antenna system. However, dual-polarized Vivaldi elements do not conform naturally to this kind of lattice and, consequently, they have not been thoroughly studied in the literature despite this well-known advantage. In this work, a novel dual-polarized fully-metallic Vivaldi element is presented. Also, the feeding network for this element is designed in the form of a suspended stripline. This technology presents low loss in comparison with a conventional stripline or microstrip. The radiating elements can be manufactured in a single piece, and they are easily integrated with the stripline feeding by just placing one on top of the other. An infinite array analysis, i.e. unit cell analysis, was performed to show the correct performance of the triangular lattice array and the proposed dual-polarized Vivaldi antenna design. A good matching was achieved over the entire band from 6 to 15 GHz for all the scanning planes and up to 60◦ scanning angle. The active element patterns show the good behaviour of the array, i.e. the absence of scan blindness and grating lobes. Finally, the unit cell analysis is compared to a finite 11×11 array for verification. / Nya generationer av mobilkommunikation behöver elektromagnetiska sensorer som kan styra sin högriktade signalenergi mot användarna. Konventionella basstationer använder kvadratiska gitterfasuppsättningar. Dessa arrayer är sammansatta av ett stort antal strålningselement för att uppnå den erforderliga höga riktningsförmågan och avsökningskapaciteten. Dessa system är av hög komplexitet och kostnad eftersom det efter varje element finns en lång elektronisk kedja. Därför är det av stort intresse att minska antalet element i arrayens apertur samtidigt som dess prestanda bibehålls. Istället för att använda ett kvadratiskt gitter för att placera de strålande elementen, kan ett triangulärt gitter användas. Det är bevisat att ett triangulärt gitter optimalt samplar aperturen och minskar elementantalet med upp till 15.5%, vilket minskar kostnaden och komplexiteten för hela antennsystemet. Dubbelpolariserade Vivaldi-element överensstämmer dock inte naturligt med denna typ av triangulära symmetri och följaktligen har de inte studerats grundligt i litteraturen trots denna välkända fördel. I detta arbete presenteras ett nytt dubbelpolariserat fullt metalliskt Vivaldi-element. Matningsnätverket för detta element är också utformat i form av en upphängd stripline. Denna metod ger låga förluster i jämförelse med en konventionell stripline eller mikrostrip. En oändlig array-analys, d.v.s. enhetscell, utfördes för att visa den korrekta prestandan för den triangulära gittermatrisen. En bra matchning uppnåddes över hela bandet från 6 till 15 GHz för alla skanningsplan och upp till 60° utstyrningsvinkel. Aktiva elementstrålnings diagrammet visar konfigurationens lovande egenskaper, d.v.s. ingen skanningsblindhet eller gallerlober. Slutligen jämförs enhetscellanalysen med en ändlig 11x11 array för verifiering.
28

Substrate integrated waveguide antenna systems

Salem Hesari, Sara 29 January 2019 (has links)
Due to high demand for planar structures with low loss, a considerable amount of research has been done to the design of substrate integrated waveguide (SIW) components in the mm-wave and microwave range. SIW has many advantages in comparison to conventional waveguides and microstrip lines, such as compact and planar structure, ease of fabrication, low radiation loss, high power handling ability and low cost which makes it a very promising technology for current and future systems operating in K-band and above. Therefore, all the work presented in this dissertation focuses on SIW technology. Five di erent antenna systems are proposed to verify the advantages of using SIW technology. First, a novel K-band end- re SIW circularly polarized (CP) antenna system on a single layer printed-circuit board is proposed. A high gain SIW H-plane horn and a Vivaldi antenna are developed to produce two orthogonal polarizations in the plane of the substrate. CP antennas have become very popular because of their unique characteristics and their applications in satellites, radars and wireless communications. Second, a K-band front-end system for tracking applications is presented. The circuit comprises an antenna array of two Vivaldi antennas, a frequency-selective power combiner, and two frequency-selective SIW crossovers, which eliminate the need for subsequent ltering. The integration of monopulse systems in planar, printed circuit SIW technology combined with the added bene ts of ltering functions is of great importance to the antennas and propagation community. Third, a phased array antenna system consisting of 24 radiating element is designed as feed system for reflector antennas in radio astronomy applications. A Ku-band antipodal dipole antenna with wide bandwidth, low cross-polarization and wide beamwidth is suggested as the radiating element. Forth, four di erent right-angled power dividers including in-phase and out-of-phase dividers as feed systems for antenna arrays are introduced. TE10 - to - TEq0 mode transducers are used for obtaining two, three, and four output dividers with phase control ability at K- and Ka-band. This feature is practical, for instance, when designing tracking systems since they are employed to obtain controllable phase distributions over the output ports. Fifth, a Ku-band beam steering antenna system which is applicable to use for wireless communications, radar systems, and also 5G applications is proposed. This antenna system uses variable reflection-type phase shifters which electrically steer the beam over a 50-degree scan range. Therefore, the SIW technology's reliability and also promising behavior in the microwave frequency range is proven for di erent applications. / Graduate
29

UWB Antennas for Wall Penetrating Radar Systems

Javashvili, Otar January 2009 (has links)
<p>Basic properties and new design principles of ultra wideband Vivaldi antennas are presentedand discussed in this paper. The focus will be on the modeling of Vivaldi antenna design curves, by which it is constructed; its simulation results, realization and the measurements.</p><p>According to the aim of this research the discussion starts with the review of the previous researches done for Vivaldi antennas. Introductory part of the report also contains the problem description for the current project and the classification of the goals to be achieved. As a theoretical review, the discussion initiates with the definitions anddescription of basic parameters of the antennas and covers a short presentation of UWBpulse-based radar system. The attention will be focused on UWB signals behavior and characterization, their propagation principles and basic troubles stands nowadays. As anapplication the wall penetrating Radar systems will be considered. The major part of thereport holds on the investigation of the design principles of Vivaldi Antenna andoptimization of the key parameters for achieving the best performance for radar. Theending part of the report shows the simulations and measurement results and theircomparisons following with conclusions/discussions.</p><p>The report will be supportive for the antenna designers, who work for UWB systems andparticularly for Vivaldi antennas, as long as there are showing up detailed descriptions ofVivaldi antenna characteristics depending on its shape and substrate properties. The modelfor designing Vivaldi antennas, given in this project, can successfully be applied for almostall the cases used in practice nowadays.</p>
30

UWB Antennas for Wall Penetrating Radar Systems

Javashvili, Otar January 2009 (has links)
Basic properties and new design principles of ultra wideband Vivaldi antennas are presentedand discussed in this paper. The focus will be on the modeling of Vivaldi antenna design curves, by which it is constructed; its simulation results, realization and the measurements. According to the aim of this research the discussion starts with the review of the previous researches done for Vivaldi antennas. Introductory part of the report also contains the problem description for the current project and the classification of the goals to be achieved. As a theoretical review, the discussion initiates with the definitions anddescription of basic parameters of the antennas and covers a short presentation of UWBpulse-based radar system. The attention will be focused on UWB signals behavior and characterization, their propagation principles and basic troubles stands nowadays. As anapplication the wall penetrating Radar systems will be considered. The major part of thereport holds on the investigation of the design principles of Vivaldi Antenna andoptimization of the key parameters for achieving the best performance for radar. Theending part of the report shows the simulations and measurement results and theircomparisons following with conclusions/discussions. The report will be supportive for the antenna designers, who work for UWB systems andparticularly for Vivaldi antennas, as long as there are showing up detailed descriptions ofVivaldi antenna characteristics depending on its shape and substrate properties. The modelfor designing Vivaldi antennas, given in this project, can successfully be applied for almostall the cases used in practice nowadays.

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