O objetivo deste trabalho é desenvolver um modelo conceitual de um sistema transmissor de pulsos eletromagnéticos de banda ultra-larga, capaz de realizar o controle da formação do feixe irradiado de forma totalmente eletrônica. Para isso, é proposto um sistema formado por quatro canais iguais e independentes, sendo que cada um é formado por um controlador de atraso programável, com o qual se pode ajustar a defasagem temporal entre os pulsos de cada canal, um gerador de pulso, capaz de sintetizar a quinta derivada do pulso Gaussiano a partir de uma nova proposta de topologia, e um arranjo de antenas do tipo planar de abertura exponencial conhecida como antena Vivaldi. O sistema proposto é apoiado por modelos matemáticos e simulações elétricas post-layout com variação dos parâmetros por Monte Carlo com os programas LTSpice 4 e Microwind 2.6, utilizando as regras de processo padrão CMOS 180nm e eletromagnética tridimensional com o uso do programa CST Microwave 2011. Os resultados obtidos nas simulações, comparados com propostas anteriores, indicam que realmente houve o controle da formação do feixe irradiado cujo lóbulo principal teve uma magnitude média de 11dBi com uma largura angular do feixe de 33º x 38º e possibilidade de variar os ângulos azimutal e de elevação de -15º a 9º e -18º a 6º, respectivamente, para uma frequência central de 6GHz. O pulso utilizado para estimular as antenas foi o pulso Gaussiano em sua quinta ordem de derivação, que teve como resultados médios de simulação uma amplitude de 90mVpp, uma largura de pulso de 370ps a uma taxa de repetição de 100MHz e uma frequência central de 6GHz. / This work aims to develop a conceptual model of the new Ultra Wide-band fifth-order derivative Gaussian pulse transmitter with Vivaldi antenna array for beamforming using the technique of timed-array. It is proposed a system formed by four equal and independent channels, each of which is formed by a programmable delay controller in which one can adjust the delay time between pulses of each channel, a pulse generator, capable to synthesize the fifth derivative of a Gaussian pulse using a new topology, and a planar Vivaldi antenna. The proposed system was supported by mathematical models and post-layout electrical simulations with parameters variation by Monte Carlo in programs LTSpice 4 and MicroWind 2.6 using the CMOS 180nm Standard process rules and using three-dimensional electromagnetic program CST Microwave 2011. The simulation results indicated that there was indeed control on the beam formation irradiated whose main lobe has an average magnitude of 11dBi with an angular width of the beam 33 x 38 (degrees square) and possibility of varying the angles of azimuth and elevation from -15 to 9 degrees and -18 to 6 degrees, respectively, at a center frequency of 6GHz. The pulse used to stimulate the antennas was the fifth order Gaussian one, which had the average results of a simulation 90mVpp amplitude, a pulse width 370ps to a 100MHz repetition rate and a center frequency of 6 GHz..

O objetivo deste trabalho é desenvolver um modelo conceitual de um sistema transmissor de pulsos eletromagnéticos de banda ultra-larga, capaz de realizar o controle da formação do feixe irradiado de forma totalmente eletrônica. Para isso, é proposto um sistema formado por quatro canais iguais e independentes, sendo que cada um é formado por um controlador de atraso programável, com o qual se pode ajustar a defasagem temporal entre os pulsos de cada canal, um gerador de pulso, capaz de sintetizar a quinta derivada do pulso Gaussiano a partir de uma nova proposta de topologia, e um arranjo de antenas do tipo planar de abertura exponencial conhecida como antena Vivaldi. O sistema proposto é apoiado por modelos matemáticos e simulações elétricas post-layout com variação dos parâmetros por Monte Carlo com os programas LTSpice 4 e Microwind 2.6, utilizando as regras de processo padrão CMOS 180nm e eletromagnética tridimensional com o uso do programa CST Microwave 2011. Os resultados obtidos nas simulações, comparados com propostas anteriores, indicam que realmente houve o controle da formação do feixe irradiado cujo lóbulo principal teve uma magnitude média de 11dBi com uma largura angular do feixe de 33º x 38º e possibilidade de variar os ângulos azimutal e de elevação de -15º a 9º e -18º a 6º, respectivamente, para uma frequência central de 6GHz. O pulso utilizado para estimular as antenas foi o pulso Gaussiano em sua quinta ordem de derivação, que teve como resultados médios de simulação uma amplitude de 90mVpp, uma largura de pulso de 370ps a uma taxa de repetição de 100MHz e uma frequência central de 6GHz. / This work aims to develop a conceptual model of the new Ultra Wide-band fifth-order derivative Gaussian pulse transmitter with Vivaldi antenna array for beamforming using the technique of timed-array. It is proposed a system formed by four equal and independent channels, each of which is formed by a programmable delay controller in which one can adjust the delay time between pulses of each channel, a pulse generator, capable to synthesize the fifth derivative of a Gaussian pulse using a new topology, and a planar Vivaldi antenna. The proposed system was supported by mathematical models and post-layout electrical simulations with parameters variation by Monte Carlo in programs LTSpice 4 and MicroWind 2.6 using the CMOS 180nm Standard process rules and using three-dimensional electromagnetic program CST Microwave 2011. The simulation results indicated that there was indeed control on the beam formation irradiated whose main lobe has an average magnitude of 11dBi with an angular width of the beam 33 x 38 (degrees square) and possibility of varying the angles of azimuth and elevation from -15 to 9 degrees and -18 to 6 degrees, respectively, at a center frequency of 6GHz. The pulse used to stimulate the antennas was the fifth order Gaussian one, which had the average results of a simulation 90mVpp amplitude, a pulse width 370ps to a 100MHz repetition rate and a center frequency of 6 GHz..

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.

Quellenforschung an Musikhandschriften der SLUB ist immer ein Erlebnis. Auch auf scheinbar ausgetretenen Pfaden ist mit Überraschungen zu rechnen ...

Factual evidence concerning the ancestry of the clarinet has been a perpetual topic of debate among musicologists and organologists. Scholars have widely agreed that the clarinet, first documented in 1710, emerged from the baroque invention of the chalumeau (invented circa 1690), which in itself was an improvement upon the recorder. Considering the chalumeau's short lifespan as the predominant single reed instrument in the early eighteenth century, the chalumeau inspired a monumental amount of literature that includes vocal and instrumental genres written by distinguished composers. Vivaldi is considered to be the most significant composer that wrote for both clarinet and chalumeau; he wrote for both instruments simultaneously throughout his life whereas his contemporaries seemingly replaced the chalumeau with the clarinet. This project will discuss Vivaldi's proximity to the chalumeau and the clarinet and will provide an in-depth analysis of relevant works by the composer to determine how he, unlike his contemporaries, treated the chalumeau and the clarinet as separate and equally viable instruments. Following a brief history of the chalumeau and clarinet in Italy and a relevant biography of Vivaldi (Ch. 2), this document will discuss the integral Vivaldi compositions that include clarinet and chalumeau and the role of the clarinet or chalumeau in each work (Ch. 3). Chapter 4 solves the mystery of why Vivaldi continued to compose for the chalumeau while his contemporaries replaced the chalumeau with the clarinet.

The aim of this thesis was to identification with the principles of logical evaluation of the position of stations on the Internet. Read up on the localization algorithm called Vivaldi with adaptive time step and subsequently to its implementation in the operating system GNU/Linux CentOS distribution. Do one's homework the PlanetLab experimental network (http://www.planet-lab.org/). At selected stations from the network transfer created by the application and verify its function on the real servers located at various places around the globe and assess the accuracy achieved by estimating the distance between stations on the PlanetLab network. In this scope of activity, the application was created to measure the delay prediction using Vivaldi algorithm with adaptive time step which is on principle of operation a client-server where the client performs the steps of the algorithm, Vivaldi and the server only listens, collects the resulting data Vivaldi algorithm and stores them neatly file. Furthermore, the application was developed for direct measurement of the delay, which also functions as a client-server. These applications have been transferred to the selected nodes from the PlanetLab experimental network. Subsequently, these nodes were running, to carry out the necessary measurements. The resulting values were work into tables of using Microsoft Excel. These values were then compared with direct measurements and competitive positioning by the King. Vivaldi localization methods with adaptive time step and the King, were compared based on calculated estimates of both real estate errors and measurement using distribution function of the relative errors of both methods. All this information was evaluated to compare accuracy of both the localization methods and direct measurements.

Studies of variation form generally overlook the works of Antonio Vivaldi due to the lack of sufficient bibliographic resources and assumptions downplaying the significance of Vivaldi's variation sets. This study, however, argues that Vivaldi's sets represent innovative contributions to the hm It begins by cataloguing the twenty instrumental variation sets published in the &st critical edition of Vivaidits works (Milan: Ricordi, 1947-72). It then examines the sequence of vatiations and manner of conclusion in each set, issues crucial to the reception of variation form ever since late eighteenth-century writers such as Koch and Vogler expanded discussions of variation technique to address variation sets as a musical farm. Vivakli's examples are compared to those by Corelli, Rarneau, and Handel, highlighting Vivaldi's greater emphasis on coherent progressions and f'lrm conclusions. Additionally, reeent chronological studies are combined to propose that Vivaldi was among the first composers to use variation form h solo concertos.

Thesis (D.M.)--Northwestern University, 1998. / Source: Dissertation Abstracts International, Volume: 63-12, Section: A, page: 4142. Adviser: Richard Alderson.

The work deals with the issues of network coordinate systems. The first chapter is devoted to a brief analysis of this systems and requirements placed on them. Furthermore, it deals with features of Vivaldi algorithm and its three versions: a centralized algorithm, algorithm with constant and adaptive time step. Subsequently it describes the GNP system and eash step of Nelder-Mead method for nodes localization. Next to it a developed simulation library is presented with its own graphical user interface for testing of these algorithms, which is capable of handling RTT responses database amongst individual IP network members. Simulations performed on data from PlanetLab network are evaluated in the conclusion.

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