Dissertations / Theses: 'Galileo'

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Nevina, Nicoletta <1964&gt. "Le avventure dantesche del giovane Galileo Galilei." Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/9402.

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Il lavoro affronta un'analisi degli scritti letterari di Galileo Galilei, meno conosciuti e certamente oscurati dai grandi trattati scientifici e si concentra specificatamente sulle due lezioni dantesche tenute all'Accademia fiorentina tra il 1588 ed il 1589

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Rivera, Victor Samuel. "Pitagorismo y legibilidad del mundo en Galileo Galilei." Pontificia Universidad Católica del Perú - Departamento de Humanidades, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/113190.

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Dorn, Matthias. "Das problem der Autonomie der Naturwissenschaften bei Galilei /." Stuttgart : F. Steiner, 2000. http://catalogue.bnf.fr/ark:/12148/cb38996157k.

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Beretta, Francesco. "Galilée devant le tribunal de l'Inquisition : une relecture des sources /." Fribourg (Suisse) : [s. n.], 1998. http://catalogue.bnf.fr/ark:/12148/cb371553984.

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Hagberg, Stephen C. "Science and the interpretation of Scripture Galileo's approach /." Theological Research Exchange Network (TREN), 1989. http://www.tren.com.

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Heichele, Thomas. "Die galileische Kosmologie - neuzeitliches Weltbild? : Wissenschaft zwischen Tradition und Moderne /." München : Akad. Verl, 2008. http://d-nb.info/990355551/04.

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Soares, Jerry Luiz. "A defesa do copernicanismo por Galileu Galilei." Universidade Federal do Amazonas, 2013. http://tede.ufam.edu.br/handle/tede/3721.

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Made available in DSpace on 2015-04-22T22:18:27Z (GMT). No. of bitstreams: 1 Jerry Luiz Soares.pdf: 672406 bytes, checksum: e88bbef6ba318d131d840409b6860292 (MD5) Previous issue date: 2013-07-18
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Galileo Galilei supported Nicolaus Copernicus astronomic theory, from which the former has attracted philosophical as well theological consequences. The celestial discoveries made possible with the usage of spyglasses allowed Galileo to challenge some of the aristotelic principles of cosmology and to break up the limits imposed to astronomy as hypothetical discipline which would aim just to "save the phenomena".
Galileu Galilei defendeu a teoria astronômica de Nicolau Copérnico, e dela extraiu consequências filosóficas e teológicas. As descobertas celestes com a utilização da luneta permitiram a Galileu questionar alguns princípios da cosmologia aristotélica, e romper os limites impostos à Astronomia, enquanto disciplina hipotética que teria como objetivo tão somente "salvar os fenômenos".

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Oliveira, Elvis Alves de. "Receptor Galileo em software." Instituto Tecnológico de Aeronáutica, 2009. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1114.

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O Galileo será o primeiro sistema de navegação global por satélite da União Européia. Além de disponibilizar dois sinais de acesso livre o Galileo irá oferecer serviços para diferentes segmentos tais como: aplicações comerciais; serviços de busca e resgate; serviços governamentais; e segurança de vidas. Tais serviços, baseados em uma constelação GPS (Global Positioning System) não são possíveis hoje. O objetivo deste estudo é a implementação de um receptor em software (Software Defined Radio - SDR) para o sinal Galileo E1-B com enfoque na geração deste sinal e nas etapas de aquisição e rastreamento. Algumas características da antena receptora, do hardware do estágio de entrada (Front-End) e considerações sobre a digitalização do sinal E1-B são descritas assim como as características dos blocos que compõem as etapas de aquisição e de rastreamento. Através destas etapas o sinal espalhado espectralmente é demodulado e os bits de navegação são recuperados.O Galileo ainda está em sua fase de implementação. Diante disto, foi necessário um trabalho extensivo de pesquisa objetivando o levantamento de suas principais características, dando enfoque ao sinal E1-B. Este sinal utiliza uma nova técnica de modulação aplicada à navegação, denominada BOC (Binary Offset Carrier), alterando assim algumas características da estrutura de processamento de um receptor GNSS convencional. Esta nova técnica utiliza uma subportadora que divide o espectro em dois lóbulos principais com um nulo na freqüência de portadora permitindo a coexistência espectral com sinais GNSS que operem na mesma freqüência de portadora do sinal E1-B além de permitir o rastreamento do sinal em ambientes com baixa relação portadora-densidade de ruído (C/No) devido ao estreitamento da função de autocorrelação.

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Degryse, Lucette. "Écriture et communication dans l'oeuvre de Galilée : étude rhétorique de la première journée du dialogue de 1632." Lille 3, 1995. http://www.theses.fr/1995LIL30009.

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L'oeuvre de Galilée (1564-1642) est abordée dans une perspective littéraire autour de deux axes principaux : le genre dialogique et les enjeux de l'écriture. L'accent est mis sur l'argumentation et les atouts du style habilement exploités pour la rendre plus séduisante. Dans la première partie, l'histoire du dialogue avant Galilée vise à éclairer les motivations d'un tel choix littéraire chez le savant décidé à livrer au public son audacieuse défense du copernicianisme. On assiste d'ailleurs à une extension du potentiel expressif de ce genre, grâce au subterfuge de la théatralisation, où s'expriment brillamment les talents de l'écrivain. La deuxième partie s'attache essentiellement aux procédés stylistiques à l'oeuvre dans la "Première journée". À partir de quelques enquêtes linguistiques, l'étude porte successivement sur dénotation et connotation, concepts modernes derrière lesquels se profile la distinction aristotélicienne entre logos, ethos et pathos. La réflexion s'oriente enfin vers les formes de littérarité que l'écrivain Galilée met au service de l'ambitieux message du savant. C'est ce lien puissant entre écriture et "forma mentis" nouvelle qui nous suggère de mettre l'accent sur l'admirable rhétorique du dialogue. Brio du style et du raisonnement, mouvement de la plume et de la pensée pour une oeuvre suspendue entre l'univers de la science et celui de l'art, qui se détache majestueusement de l'esthétisme pré-baroque
Galileo 's work is tackled in a literary perspective aroun two main lines of study : the dialogical genre and the stakes of style. The emphasis is put upon the argumentation and assets of qualities of style, skillfully exploited in order to make it more attractive. In the first part, the history of the dialogue before galileo aims at throwing light on the motivations of such a literary choice for the scholar determined to put forward to the public his bold defence of copernicanism. Besides, we can witness and extension of the expressive potential of the genre, thanks to the subterfuge of theatralisation in which the raconter 's talents can express themselves brilliantly. The second part is mainly devoted to the figures of speech used in the first day. From a few linguistic researches, the study deals successively with denotation and connotation, modern concepts behind which emerges the aristotelian difference between logos, ethos and pathos. The reflection eventually directs itself toward the literary forms which galileo, as a writer, puts at the service of the scientist's ambitious message. It is this powerful link between style and "forma mentis" which suggest to us to put the emphasis on the dialogue's admirable rhetoric. Brilliancy of the style and of reflection strokes of pen and thought for a work hanging between the world of science and art, which is majestically brought out of pre-baroque aestheticism

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Garcia, Stéphane. "Élie Diodati et Galilée : naissance d'un réseau scientifique dans l'Europe du XVIIe siècle /." Firenze : L. S. Olschki, 2004. http://catalogue.bnf.fr/ark:/12148/cb399618794.

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Bensoussan, Denis. "GNSS and Galileo Liability Aspects." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=93845.

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In the next coming years global satellite navigation systems (GNSS) will make part of our daily life, as the world is becoming "GNSS-dependant in the same way that it has become Internet-dependant". Indeed, more than ten years folowing the opening up to civilians of satellite-based navigation systems initially designed for military purposes, civil satellite navigation applications are becoming more and more numerous. The potential benefits have proven enormous in terms of transport safety and efficiency as well as for non-transport-related industries.
Dans les toutes prochaines années, les systèmes globaux de navigation par satellite (GNSS) feront partie intégrante de notre vie quotidienne. En effet, un peu plus de dix ans après la libéralisation de l'accès des civils aux systèmes de navigation par satellite initialement conçus à des fins militaires, les applications civiles permises par la navigation par satellite sont de plus en plus nombreuses et les bénéfices potentiels sont énormes en matière de sécurité et d'efficacité des transports comme pour d'autres secteurs et industries. fr

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Ortega, Espluga Lorenzo. "Signal optimization for Galileo evolution." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0118.

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Les systèmes mondiaux de navigation par satellite (GNSS) sont de plus en plus présents dansnotre vie quotidienne. Des nouveaux utilisateurs émergent avec des besoins opérationnelssupplémentaires, ce qui implique une évolution constante des systèmes de navigation actuels.Dans le cadre de Galileo (système GNSS européen) et en particulier dans Galileo E1 OpenService (OS), l’addition d’un nouveau signal d’acquisition pourrait contribuer à améliorer larésilience dans la phase d’acquisition et à réduire le temps pour géo-localiser notre récepteur(TTFF). La conception d'un nouveau signal GNSS est toujours un compromis entre plusieursfigures de mérite. Les plus pertinents sont la précision de la position, la sensibilité de récepteur etle TTFF. Cependant, si l’on considère que la phase d’acquisition du signal le principal objectif, lasensibilité et le TTFF ont une pertinence plus grande. Compte tenu de ce qui précède, dans cettethèse, il est présenté la conception conjointe d'un signal GNSS avec la structure de message afinde proposer un nouveau signal Galileo de deuxième génération, qui offre bonne sensibilité derécepteur ainsi que une réduction dans le TTFF. Plusieurs aspects ont été abordés afin deconcevoir la nouvelle composante de signal. Premièrement, la définition de la modulation doitprendre en compte la compatibilité des fréquences radioélectriques afin de provoquer un niveaude brouillage acceptable dans la bande. De plus, la modulation devrait fournir de bonnespropriétés de corrélation et une bonne résistance contre les multi trajets afin d'améliorer lasensibilité du récepteur. Deuxièmement, le choix du nouveau code PRN est également crucialpour faciliter la phase d’acquisition. Un critère de modélisation basé sur une fonction de coûtpondéré est utilisé pour évaluer la performance des codes PRN. Cette fonction de coût considèredifférent facteurs telles que l'autocorrélation, la corrélation croisée et la densité spectrale depuissance. Troisièmement, une conception conjointe entre la structure de message et le schémade codage de canal peut fournir à la fois une réduction du TTFF et une amélioration de larésilience des données décodées. Alors, une nouvelle méthode de conception de la structure demessage et du schéma de codage de canal pour le nouveau signal est proposée. Cette méthodefournit les instructions pour concevoir une structure de message dont le schéma de codage decanal est caractérisé pour les propriétés full diversity, maximum distance separable et ratecompatibility. Le codage de canal est essentiel pour améliorer les performances de démodulationde données, en particulier dans les environnements très obstrué ou avec d’interférences.Cependant, ce processus peut être très sensible au calcul correct de l'entrée du décodeur. Desaméliorations significatives ont été obtenues en considérant «soft » décodeurs, via le calcul deslog-likelihood ratio (LLR). Malheureusement, la connaissance complète des informations d'état ducanal (CSI) était généralement prise en compte, ce qui est rarement le cas dans des scénariosréels. Dans cette thèse, nous fournissons de nouvelles méthodes pour calculer desapproximations linéaires du LLR, sous les canaux de fading et interférence, en considérantcertaine information statistique sur le CSI. Finalement, transmettre un nouveau signal dans lamême fréquence porteuse et en utilisant le même amplificateur de puissance (HPA) génère descontraintes dans les méthodes de multiplexage, car une enveloppe constante ou quasi constanteest nécessaire pour réduire les distorsions non linéaires. Également, la conception dumultiplexage devrait offrir une efficacité énergétique élevée afin de ne pas gaspiller l'énergietransmis du satellite. Considérant le précédent, dans cette thèse, nous évaluons différentesméthodes de multiplexage, qui cherchent l’intégration de un nouveau signal binaire dans la bandeGalileo E1
Global Navigation Satellite System (GNSS) are present in our daily lives. Moreover, new users areemerging with further operation needs involving a constant evolution of the current navigationsystems. In the current framework of Galileo (GNSS European system) and especially within theGalileo E1 Open Service (OS), adding a new acquisition aiding signal could contribute to providehigher resilience at the acquisition phase, as well as to reduce the time to first fix (TTFF).Designing a new GNSS signal is always a trade-off between several performance figures of merit.The most relevant are the position accuracy, the sensitivity and the TTFF. However, if oneconsiders that the signal acquisition phase is the goal to design, the sensitivity and the TTFF havea higher relevance. Considering that, in this thesis it is presented the joint design of a GNSS signaland the message structure to propose a new Galileo 2nd generation signal, which provides ahigher sensitivity in the receiver and reduce the TTFF. Several aspects have been addressed inorder to design a new signal component. Firstly, the spreading modulation definition must considerthe radio frequency compatibility in order to cause acceptable level of interference inside the band.Moreover, the spreading modulation should provide good correlation properties and goodresistance against the multipath in order to enhance the receiver sensitivity and to reduce theTTFF. Secondly, the choice of the new PRN code is also crucial in order to ease the acquisitionphase. A simple model criterion based on a weighted cost function is used to evaluate the PRNcodes performance. This weighted cost function takes into account different figures of merit suchas the autocorrelation, the cross-correlation and the power spectral density. Thirdly, the design ofthe channel coding scheme is always connected with the structure of the message. A joint designbetween the message structure and the channel coding scheme can provide both, reducing theTTFF and an enhancement of the resilience of the decoded data. In this this, a new method to codesign the message structure and the channel coding scheme for the new G2G signal isproposed. This method provides the guideline to design a message structure whose the channelcoding scheme is characterized by the full diversity, the Maximum Distance Separable (MDS) andthe rate compatible properties. The channel coding is essential in order to enhance the datademodulation performance, especially in harsh environments. However, this process can be verysensitive to the correct computation of the decoder input. Significant improvements were obtainedby considering soft inputs channel decoders, through the Log Likelihood Ratio LLRs computation.However, the complete knowledge of the channel state information (CSI) was usually considered,which it is infrequently in real scenarios. In this thesis, we provide new methods to compute LLRlinear approximations, under the jamming and the block fading channels, considering somestatistical CSI. Finally, to transmit a new signal in the same carrier frequency and using the sameHigh Power Amplifier (HPA) generates constraints in the multiplexing design, since a constant orquasi constant envelope is needed in order to decrease the non-linear distortions. Moreover, themultiplexing design should provide high power efficiency to not waste the transmitted satellitepower. Considering the precedent, in this thesis, we evaluate different multiplexing methods,which search to integrate a new binary signal in the Galileo E1 band while enhancing thetransmitted power efficiency. Besides that, even if the work is focused on the Galileo E1, many ofthe concepts and methodologies can be easily extended to any GNSS signal

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Чернюк, Євген Олегович. "Оцінка точності супутникової системи GALILEO." Thesis, Національний авіаційний університет, 2020. http://er.nau.edu.ua/handle/NAU/41857.

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Робота публікується згідно наказу ректора від 21.01.2020 р. №008/од "Про перевірку кваліфікаційних робіт на академічний плагіат 2019-2020р.р. навчальному році" . Керівник проекту: доцент, к. т. н. Погурельський Олексій Сергійович
Станом на початок 2020 року в світі функціонує 4 глобальних навігаційні супутникові системи. Кожна з них є реалізацією складної в технічному і затратної в фінансовому плані задачі. Глобальна супутникова навігаційна система це не лише сузір’я супутників але і складна наземна інфраструктура розподілених по земній поверхні станцій моніторингу та спостереження, прийому та завантаження спеціальної службової інформації, головний та резервний центри управління. Через цю складність реалізувати перші системи вдалося потужним країнам, чий військовий бюджет осилив цей тягар: Сполученим Штатам Америки (система GPS), Радянському Союзу на початковому етапі і Російській Федерації на завершальному (система ГЛОНАСС), а також Китайській Народній Республіці (система BeiDou). [2, 3, 11] Спільним у створенні цих систем була мета – забезпечення потреб військової сфери у високоточному глобальному сервісу позиціонування та наведення. Широке розповсюдження технологій супутникової навігації в цивільній сфері було лише похідною від тих можливостей які забезпечили розгорнуті системи військовим. Розвиток і основні віхи в становленні систем глобального позиціонування були пов’язані з політичним протистоянням на світовій арені. Як наслідок, на сьогоднішній день можна констатувати факт наявності надзвичайно зручних і ефективних засобів для глобального позиціонування, які при цьому не надають жодних гарантій цивільним користувачам на наявність і доступність своїх сигналів і сервісів у майбутньому. [4, 11, 12] Створення і розгортання глобальної навігаційної супутникової системи повністю цивільного призначення значно відрізняє на цьому тлі європейський проект Galileo. Він пройшов складний шлях від ідеї і загальної концепції до свого нинішнього етапу, коли система стоїть на порозі повноцінного функціонування з досягнутою номінальною кількістю космічних апаратів. Орієнтована на потреби цивільних і перш за все авіаційних користувачів, система Galileo забезпечуватиме доступ до сигналів високоточної навігації на комерційній основі зі збереженням безкоштовних відкритих сервісів. [5,19] Поточна стадія функціонування системи Galileo дозволяє планувати і виконувати комплексні дослідження її характеристик в режимі одно системної обробки даних та у сполучені з даними від інших існуючих систем. Завдяки організації довготривалого моніторингу з’являється можливість відслідковувати еволюційні зміни, які відбуватимуться в системі разом з нарощуванням кількості супутників на орбіті. Ці задачі можуть бути продовженням результатів одержаних в цій роботі, присвяченій оцінці точності глобальної навігаційної супутникової системи Galileo.

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Coada, Paul, and Erkut Kaya. "Implementing Erlang/OTP on Intel Galileo." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177510.

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The Intel Galileo, inspired by the well-known Arduino board, is a development board with many possibilities because of its strength. The Galileo is has an Intel processor capable of running GNU/Linux and can be connected to the internet, which opens up the possibility to be controlled remotely. The programming language that comes with the Intel Galileo is the same as for the Arduino development boards, and is therefore very limited and does not utilize the Galileo’s entire strength. Our aim with this project is to integrate a more suitable programming language; a language that can make better use of the relatively powerful processor to control the components of the board. The programming language of choice is Erlang, and the reason is obvious. Erlang can be described as a process-oriented programming language based on the functional programming paradigm and its power in concurrency. The result of the project was the successful integration of a complete version of GNU/Linux on the board and the cross-compilation of Erlang/OTP onto the board. Having Erlang running on the system opens up many possibilities for future work, amongst all: creating Erlang programs for the Intel Galileo, integrating an effective API, and measuring the pros and cons of using Erlang on an Intel Galileo.
Intel Galileo är ett utvecklingskort som bygger på Arduinos succe. Den kommer med en kraftigare processor jämfort med Arduino Uno, och den har möjlighet att kunna köra GNU/Linux. Den har också en port för att kunna kopplas till internet och på så sätt kommunicera med andra enheter. Programmeringsspråket som rekommenderas för Intel Galileo är densamma som används för Arduinos utvecklingskort. Det finns däremot en möjlighet att kunna kombinera utvecklingskortet med ett programmeringsspråk som kan erbjuda mer funktionalitet och fortfarande vara enkelt. Vårt val hamnade på Erlang för den är ett funktionellt språk och har möjlighet att hantera olika processer. Tanken är att kunna behandla olika komponenter kopplade till utvecklingskortet som processer, som kan kommunicera med andra komponenter och med internet. Projektarbetet bestod av att undersöka ifall det är möjligt att kunna kombinera Erlang/OTP med Intel Galileon samt skriva en guide för hur implementeringen gick till. Att kombinera de två var lyckat och det öppnar upp möjligheter för fortsätta arbeten och försök.

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Zhi, Chen, and Zhang Qishan. "Analysis of Galileo and GPS systems." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/606699.

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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
This paper describes key points in the field of Galileo application abroad spacecraft and normal vehicles. On the basis of ephemeris of Galileo constellation, the mathematic model and procession are given in high dynamic signal environment, the digital simulation is also completed, the results are statistics and analyzed and presented. On the topic of navigation satellite constellation orbit and visibility, the paper presents the Galileo frame system, time system, navigation satellite orbit elements, constellation structure, and GDOP calculation. The users include low dynamic as well as high dynamic spacecraft. The analysis for relevant GPS is also showed. About the navigation signal structure, main points are Galileo system working frequency, including E5, E6 and L1 frequency spans, the modulation and navigation data, ets. At the same time, this paper compares Galileo with GPS. On the aspect of signal communication link, Dopplar frequency shift and power level calculation are present as well as compare with GPS system.

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Teeling, Michael J. "Geology of Galileo Regio quadrangle, Ganymede." Kansas State University, 1987. http://hdl.handle.net/2097/18557.

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Marzo, Llorca Mar. "The transposon Galileo in the Drosophila genus." Doctoral thesis, Universitat Autònoma de Barcelona, 2011. http://hdl.handle.net/10803/83991.

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Els elements transposables (TEs) són seqüències repetitives amb el tret definitori de canviar la seva posició al genoma. Ocupen fraccions importants dels genomes eucariotes, y, tot i que solen considerar-se paràsits genètics, també s'especula amb la possibilitat de que tinguessin alguna funció cel·lular que encara ens és desconeguda. Tot i així, sembla evident que tenen un paper important com facilitadors de l'evolució, ja que generen variabilitat al genoma de l'hoste. El TE Galileo està implicat en la generació de reordenacions cromosòmiques adaptatives naturals a l'espècie Drosophila buzzatii, en la que hauria generat variabilitat amb valor adaptatiu per a l'hoste. A més, tots els elements Galileo trobats en treballs anteriors eren defectius – composats bàsicament d'estructures similars a la dels elements Foldback – i no es van poder establir relacions d'homologia amb ninguna seqüència coneguda. Amb aquest rerefons, en aquesta tesi es va plantejar caracteritzar l'element genètic mòbil Galileo en diferents espècies de Drosophila i analitzar la seva dinàmica evolutiva. D'aquesta forma, en una primera fase es van buscar elements Galileo complets en diferents espècies del gènere Drosophila: D. buzzatii, D. mojavensis, D. virilis, D. willitoni, D. ananassae, D. pseudoobscura i D. persimilis, fent servir tant mètodes bioinformàtics com experimentals (depenent de si el genoma analitzat estava seqüenciat o no). Les còpies trobades presenten llargues Repeticions Invertides Terminals (TIR) de fins a 1,2 Kb, una elevada identitat amb seqüències de Galileo descrites anteriorment i, a més, contenen una zona codificant que ha permès classificar Galileo com a membre de la superfamília de l'element P. Posteriorment, mitjançant anàlisis filogenètiques, hem trobat l'existència de subfamílies de Galileo en tres espècies (D. buzzatii, D. mojavensis, D. virilis) i evidència d'activitat transposicional recent (D. willitoni, D. ananassae, D. pseudoobscura, D. persimilis i D. mojavensis). En una segona fase de la tesi, hem dut a terme experiments amb part de la proteïna que es codifica a Galileo i hem comprovat que interacciona amb les TIR de Galileo, confirmant que aquesta seqüència és la responsable de la reacció de transposició. Finalment, hem analitzat en detall la diversitat de Galileo al genoma de D. mojavensis i hem detectat una diversitat estructural molt important, on l'intercanvi de seqüències entre elements pareix força freqüent per l'evolució dels TEs.
Los elementos transponibles (TEs) son secuencias repetitivas cuya característica definitoria es la capacidad de cambiar de posición en el genoma. Ocupan fracciones muy importantes de los genomas de eucariotas, y aunque se suelen considerar parásitos genéticos, también se especula con la posibilidad de que pudieran tener alguna función celular que aún nos es desconocida. No obstante, parece evidente que tienen un papel importante como facilitadores de la evolución, al generar variabilidad en el genoma del huésped. El TE Galileo está implicado en la generación de reordenaciones cromosómicas adaptativas naturales en la especie Drosophila buzzatii, con lo que habría generado variabilidad adaptativa para el huésped. Además, todos los elementos Galileo encontrados en trabajos anteriores eran defectivos – compuestos básicamente de estructuras similares a las de los elementos Foldback – y no se pudieron establecer relaciones de homología con ninguna secuencia conocida. Con este trasfondo, en esta tesis se planteó caracterizar el elemento genético móvil Galileo en diferentes especies de Drosophila y analizar su dinámica evolutiva. De esta manera, en una primera fase se buscaron elementos Galileo completos en en diferentes especies del género Drosophila: D. buzzatii, D. mojavensis, D. virilis, D. willitoni, D. ananassae, D. pseudoobscura y D. persimilis, utilizando métodos tanto bioinformáticos como experimentales (dependiendo de si el genoma analizado estaba secuenciado o no). Las copias encontradas presentan largas Repeticiones Invertidas Terminals (TIR) de hasta 1,2 Kb, una elevada identidad con secuencias de Galileo descritas con anterioridad y, además, contienen una zona codificante que ha permitido clasificar Galileo como miembro de la superfamilia del elemento P. Posteriormente, mediante análisis filogenéticos, hemos encontrado la existencia de subfamilias de Galileo en tres especies (D. buzzatii, D. mojavensis, D. virilis) y evidencias de actividad transposicional reciente (D. willitoni, D. ananassae, D. pseudoobscura, D. persimilis y D. mojavensis). En una segunda fase de la tesis, hemos llevado a cabo experimentos con parte de la proteína que codifica Galileo y hemos comprobado que interacciona con las TIR de Galileo, confirmando que esta secuencia es la responsable de la reacción de transposición. Finalmente, hemos analizado en detalle la diversidad de Galileo en el genoma de D. mojavensis y hemos detectado una diversidad estructural muy importante, lo que sugiere que el intercambio de secuencias entre elementos podría ser bastante frecuente para la evolución de los TEs.
Transposable elements (TE) are repetitive sequences whose ability to change their location in the genome defines them. They made up a important proportion of the eukaryotic genomes, and although they are often considered as genetic parasites, it has been also argued that they might have some still unknown cellular function. Nevertheless, it is clear that they play a role as drivers of their host evolution, due to the fact that TEs generate genetic variability. The TE Galileo is involved in the generation of adaptive chromosomal rearrangements in natural populations of Drosophila buzzatii, indicating that it would be a driver of adaptation in its host. Moreover, all Galileo elements found in previous works were incomplete – mainly composed by Foldback-like structures – and homology relationships could not be established with any known sequence. With this background, this thesis was proposed to characterise the mobile genetic element Galileo in different Drosophila species and analyse its evolutionary dynamics. Thus, in a first phase we searched for complete copies of Galileo in different species of the Drosophila genus: D. buzzatii, D. mojavensis, D. virilis, D. willitoni, D. ananassae, D. pseudoobscura and D. persimilis, using both bioinformatic and experimental methods (depending on whether the analysed genome was available or not). The copies found present long TIR (up to 1.2 Kb), high sequence identity with previously found Galileo sequences and, moreover, they harbour coding sequences that have allowed the classification of Galileo as a member of the P-element superfamily. Subsequently, by means of phylogenetic analyses, we have found that there are Galileo subfamilies in three different species (D. buzzatii, D. mojavensis, D. virilis) and evidence of recent transpositional activity (in D. willitoni, D. ananassae, D. pseudoobscura, D. persimilis and D. mojavensis). In a second phase of the thesis, we have conducted experiments with part of the Galileo protein and detected specific binding to the Galileo TIR, confirming that this sequence is responsible for the transposition reaction. Finally, we have thoroughly studied the Galileo variability in the D. mojavensis genome and found a striking structural variation, suggesting that the exchange of sequences among different Galileo copies might be quite common and important for TEs evolution.

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18

Carlsson, Daniel, and Johan Johansson. "Utvärdering av Galileo GNSS med statisk mätning." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78691.

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Galileo är ett Global Navigation Satellite System (GNSS) som används för positionering. Förutom Galileo finns även Global Positioning System (GPS) och Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) vilka är de idag enda fullt operativa systemen. Galileo som är under utveckling har i april år 2020 26 satelliter i bruk och förväntas vara fullt operativt under 2020 med en konstellation av 30 satelliter. Vid statisk mätning används GNSS-teknik där minst två mottagare samlar observationer samtidigt under långa sessioner där positionen erhålls med efterberäkning. Syftet med denna studie var att undersöka huruvida Galileo genom statisk mätning kan tillföra lägre mätosäkerhet i olika GNSS-konstellationer tillsammans med GPS och GLONASS. Tvångscentrering utfördes över två kända positioner med mätning över två dagar på totalt 12 timmar. I efterberäkningen delades sessionerna in i 45 minuters observationer över fyra sessioner. Fem olika konstellationer av GNSS jämfördes: GPS, GPS och Galileo, GPS och GLONASS, Galileo och till sist där alla tre system användes ihop. Resultatet visade på en god precision med en lägesosäkerhet något större än förväntat. Session 1 fick högst värde på 4,7 cm från stompunkten. Lägst värde fick session 4 på 1,1 cm. Standardosäkerheten var däremot låg för alla konstellationer i sessionerna. Slutsatsen är att Galileo och GPS fick som enskilda konstellationer ett likvärdigt resultat för standardosäkerheten med statisk mätning. I gemensamma GNSS-konstellationer förbättras mätosäkerheter och indikerar även att användning av Galileo ger en förbättring i kombination med GPS och GLONASS.
Galileo is a new Global Navigation Satellite System (GNSS) which is still under development and is expected to be fully operational in 2020. Besides Galileo there are also the Global Positioning System (GPS) and the Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) which are the only fully operational systems as of April 2020. The purpose of this study was to evaluate whether Galileo can provide better measurement accuracy in different GNSS constellations together with GPS and GLONASS through static surveying. Many scientific studies of Galileo GNSS have been done recently, and since additional satellites have become available the accuracy of the system has been increasing. This study uses static surveying method in order to evaluate Galileo’s positioning accuracy. Measurements over two known positions was done with post calculations to remove sources of error. The study shows that Galileo and GPS obtained as individual constellations an equivalent result, and in joint GNSS constellations Galileo shows improvements in combination with GPS and GLONASS.

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Berggren, Anna. "Inledande försökt till mätning med Europas navigeringssystem Galileo." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-138994.

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Europe is presently building up a satellite navigation system of their own, Galileo. Unlike the American system, GPS, and the Russian system, Glonass, Galileo will be a civilian system. It will be independent from, but interoperable with both GPS and Glonass. After many delays have enough satellites been launched and placed in orbit to make it possible to start up Galileo’s initial services during December 2016. This study gives an account of the construction and development of the Galileo system. During two weeks in the spring 2016 experimental RTK measurements were made with Galileo combined with GPS where the satellite corrections were distributed from Lantmäteriet’s (the Swedish mapping, cadastral and land registration authority’s) supportsystem for satellite positioning, SWEPOS. The measurements were carried out with singlestation RTK towards a SWEPOS reference station at Mosebacke on Södermalm in Stockholm. The rover was placed over a fixed point about 1.2 km from the reference station.The purpose of the study was to determine if it was possible in the spring 2016 to make any measurements with Galileo and to see what Galileo can add to RTK measurements combined with GPS in SWEPOS. During the spring 2016 it was not possible to make any measurements with only Galileo satellites due to the fact that there were too few satellites in orbit. The results from the measurements indicate that combining Galileo and GPS could be positive for network RTK in SWEPOS. The part of achieved fixed solutions increases, the average time until fixed solution is achieved shortens and the space vehicle geometry (PDOP) gets a better value when combining GPS and Galileo. It is however too soon to say anything certain about the influence of Galileo on the position uncertainty.
Europa håller på att bygga upp ett eget satellitnavigeringssystem, Galileo. Till skillnad från det amerikanska systemet GPS är Galileo ett civilt system som kommer att vara oberoende av, men kompatibelt med, GPS och den ryska motsvarigheten Glonass. Efter stora förseningar har nu tillräckligt många satelliter placerats i omloppsbana så att det kan vara möjligt att starta upp Galileos tidiga tjänster (initial services) under december 2016. Detta arbete belyser Galileos uppbyggnad och utveckling. Under våren 2016 gjordes testmätningar med Galileo kombinerat med GPS där korrigeringsdata erhölls från Lantmäteriets stödsystem SWEPOS. Mätningarna gjordes med enkelstations-RTK mot SWEPOS referensstation Mosebacke på Södermalm i Stockholmöver en punkt belägen ca 1,2 km från Mosebacke. Syftet var att se om det under våren 2016 gick att göra mätningar mot Galileo och undersöka vad Galileo skulle tillföra RTK-mätning tillsammans med GPS i SWEPOS. Det var inte möjligt under våren 2016 att utföra mätningar mot enbart Galileo då det vid tidpunkten för mätningarna inte fanns tillräckligt många satelliter i omloppsbana. Resultaten från mätningarna i denna studie tyder på att Galileo tillför bättre satellittäckning vid RTK-mätning tillsammans med GPS, andelen fixlösningar ökar, tiden till att fixlösning erhålles blir kortare och satellitgeometrin blir bättre. Det ärdäremot för tidigt att med säkerhet uttala sig om Galileos påverkan på positionsosäkerheten, både i plan och höjd.

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20

Ledohowski, Lea J. (Lea Joel), and James J. Perrine. "Galileo Lofts : a real estate development feasibility study." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33184.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2005.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (leaves 176-179).
In August 2004, a development proposal titled "Galileo Lofts at MIT: Housing and Urban Park" was submitted to the Cambridge Redevelopment Authority for the provision of new housing and a public park on Parcel 7, in Kendall Square, Cambridge, MA. This study is a feasibility analysis of the development proposal. A market analysis and a marketability study were conducted to determine the appropriateness of the proposal for the East Cambridge, Kendall Square market. Demographic analysis identified two primary submarkets: 1) Cambridge Condo Submarket (i.e. demand for the location); 2) Loft Product Submarket (i.e. demand for the product type). To analyze supply and pricing, transaction data for the sale of condominiums within a one-mile radius of the proposed site, and data for the sale of comparable loft condominiums in the Greater Boston Area, were downloaded. Tests performed include descriptive statistics, regression analysis, and attribution analysis. A capital budget was estimated and a development model created to determine the financial feasibility of the proposal. Results indicated that the demand for residential products in the East Cambridge neighborhood priced for the "entry-level buyer" (i.e. up to $550,000) was not being met by current levels of supply, and it was predicted that demand for products priced at the entry-level would continue.
(cont.) It was also illustrated that demand for "luxury" products does exist in East Cambridge, but that the luxury consumer has demonstrated a preference for properties with high-end amenities and water adjacency. The Feasibility Analysis concluded that the proposed project is not viable in financial terms. It was suggested that the original proposal is not ideally suited to capture the demand in either the entry-level or luxury markets. The primary observations were that the planned residential units are too large to target the entry level buyer, and that the location, lack of amenities and rental townhouses at the ground level are expected to be problematic in the pursuit of the "luxury" buyer. It was recommended that the developers reduce the unit sizes in order to satisfy the requirements of the primary target market and redistribute the affordable rental units within the building to avoid a potential problem with marketability and management. These changes, however, would not be sufficient to turn the proposed Galileo Lofts at MIT into a financially viable project because 40% of the units are required to be affordable, and these units cost $180,000 more to produce than they would generate in sales revenue. Other relief would be needed: some suggestions are given.
by Lea J. Ledohowski and James J. Perrine.
S.M.

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21

MALARA, IVAN GIUSEPPE. "GALILEO: CREATION AND COSMOGONY. A STUDY ON THE INTERPLAY BETWEEN GALILEO'S SCIENCE OF MOTION AND THE CREATION THEME." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/851519.

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The relationship between science and theology in Galileo’s work is usually studied with reference to the Copernican letters and the so-called ‘Galileo affair,’ ended with Galileo’s abjuration in 1633. This dissertation tackles the same subject, but from a different angle. Galileo’s approach to the creation theme does indeed allow us to inquiry into the relationship between science and theology while keeping Biblical exegesis and Galileo’s trial on the background. The dissertation is divided into two parts: (1) “Creation,” and (2) “Cosmogony.” In the first part, a series of primary sources are considered (Benedetto Castelli’s letter to Galileo of April the 1st, 1607; a few unpublished folios from the reportationes of Muzio Vitelleschi’s course on natural philosophy held at the Roman College in 1589-90; some passages of Galileo’s Juvenilia) which help us gauge, albeit indirectly, Galileo’s attitude toward the possibility of demonstrating creatio de novo (the beginning of the world) and creatio ex nihilo (the existential dependence of creatures on God). Although some initial supporters of Galileo sought to demonstrate creatio de novo through his definition of motion, he never welcomed their attempt. He probably agreed with Castelli that the demonstration of creatio de novo was beyond the reach of his science and, in general, of human knowledge (a position that, for the sake of convenience, I have referred to as ‘agnosticism’). As regards creation out of nothing, at Galileo’s time this notion was usually treated in light of a metaphysical understanding of the relationship between God and creatures – a relationship which entailed an understanding of God as primum ens (first being). This notion is also used in the Juvenilia, namely, a series of pages reporting standard arguments of Scholastic philosophy, which Galileo copied from other sources. I have interpreted the total absence of the idea of God as primum ens in the original writings of Galileo as a sign that Galileo was not interested in the problem of creatio ex nihilo, nor did he consider its metaphysical solution. In the second part, I have argued that Galileo was interested in the cosmogony problem, namely, he tried to understand how God imposed order on the primeval chaotic universe. Cosmogony was refuted in the Aristotelian tradition on the basis that motion and gravity cannot be conceived of out-side the orderly framework of the universe. In this view, mechanics leans on cosmology, and vice versa. Galileo separates the two, but through cosmogony he tries to reconcile his cosmological views (initially geocentric, then heliocentric) with his understandings of motion and gravity. Thanks to Copernicus, he is able to ‘mathematize’ the cosmogony problem. Thus, the solution to this problem becomes an important scientific task, one that allows Galileo to advocate the relevance of his science on a universal scale.

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22

Calemme, Angelo. "La modernidad política clásica y la filosofía experimental." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/402515.

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El presente trabajo establece los siguientes puntos fundamentales: 1) que la elaboración ontológica galileana del concepto metafísico de una naturaleza independiente y de un pensamiento automático y objetivo de las cosas ha revolucionado de una manera histórica la cultura institucional y popular de los siglos XVI y XVII, orientando un nuevo horizonte de sentido; 2) que en su totalidad la revolución de Galileo tuvo su primer y crucial desarrollo en la propagación, académica y urbana, de una mera opinión, que, en un momento dado, se convirtió, en un primer momento en convicción política y luego en saber social; 3) que el galileismo, basado en el consenso que fue capaz de determinar en tomo suyo, llegó a organizar la lucha política de los innovadores contra las autoridades tradicionales en el campo de la ciencia; 4) que el alcance político-filosófico de la ciencia galileana del movimiento se remonta al valor performativo de sus palabras y a lo tecnológico de sus objetos; que, sobre todo después de la síntesis newtoniana, el galileísmo se ha convertido en el símbolo de la modernidad clásica no tanto sobre la base de sus descubrimientos, en parte erróneos, sino por causa de la definición físico-matemática de la naturaleza y por la elección decisiva del objeto técnico como organon del conocimiento. La presente tesis se estructura en tres capítulos que a través de los textos mismos se cortocircuitan en torno al mito científico galileano de la independencia de la naturaleza con respecto a Dios, a la salida de Dios de la escena del mundo y a la concepción de la historia como un avance tecnológico del conocimiento, tres concepciones fundamentales de las que la filosofía experimental no puede prescindir. A través de esta operación, la primera parte del primer capítulo, propondrá una mirada sobre el joven Galileo; es decir, sobre la primera fase de su pensamiento. Observaremos aquí que Galileo, aun manteniendo a grandes rasgos su peripatetismo hasta el 1602/1604, empezó a sentir a partir de 1590/1595 una cierta impaciencia y disgusto ante la autoridad de Aristóteles; que lo llevaron lenta pero firmemente a despegarse de manera crítica de la ontología tradicional, integrando progresivamente la astronomía de Copérnico con una nueva concepción del movimiento y de la estructura de la materia derivada del estudio simultáneo sobre la estática e hidrostática de Arquímedes y el atomismo democríteo. En los primeros pasos de los Juvenilia, del De motu, de las Mecaniche y, sobre todo, en el periodo comprendido entre 1602/07, mostraremos que, independientemente de la construcción del telescopio, Galilei esbozó ya las piedras angulares de la física sublunar en un sistema heliocéntrico. En la segunda parte del primer capítulo hemos llamado la atención sobre el período de incubación del Sidereus Nuncius, en el que Galileo pasó de la elaboración de un realismo platónico a la elaboración de un realismo telescópico, con el que fue finalmente posible para él ver con sus propios ojos lo que antes de 1610 era sólo una cuestión de opinión y simpatía. En el segundo capítulo, analizamos, a partir de lo dicho anteriormente, el cambio en la filosofía experimental sucesivo al 1616, es decir, desde su fase crítica a la controversia, a través de las obras de la madurez. En el tercer capítulo hemos dado una mayor contextualización a lo que hemos expuesto en los dos primeros capítulos y, a través de las obras publicadas por los peripatéticos contra la filosofía de Galileo, acentuamo los efectos políticos de la verdad con la que Galileo, en la disputa contra los aristotélicos, trazó los contornos finales de la Nueva ciencia y con ellos la “modernidad clásica”.
In order to start a genealogy of the strong sciences demonstrates the following points: 1) the Galileian metaphysical concepts of the nature’s independence and of technological object, revolutionized historically the European culture of the XVI-XVII centuries and opened a new horizon of sense; 2) the development of the galileian nature’s philosophy from mere opinion to public conviction and from political conviction to scientific knowledge; 3) the galileism by common consent organized and identified political struggle of the innovators against the traditional authorities on science; 4) they political and philosophical importance of the galileian science is due to the performative and technological value of its words and objects; galileism, expecially after the Newtonian synthesis, became the symbol of the classical modernity not because of his discoveries but thanks to the physical-mathematical definition of the nature and to the revaluation of the technical object as instrument (organon) for knowledge. Thesis is structured of three chapters that, on the basis of the literary sources, show how Galileo invented the nature’s scientific mith of independence from history knowledge and the concept of knowledge’s history as progress. In the first chapter was possible discover the Galileo’s thought beyond the traditional approaches and studied the juvenile works, where we observe that the young Galileo, despite being an Aristotelian until 1602/1604, already from 1590/1595 started to express intolerance to Aristotele’s authority. This intolerance led him away critically from the traditional ontology in Juvenilia, in De motu and Mecaniche and, specially between 1602 and 1607, integrated Copernico’s astronomy with Archimedean hydrostatic and democritean materialism and defined the principles of his new physic in a heliocentric system. In the second half of the first chapter, Galileo moved from platonic realism to telescopic realism that allowed him to see with his own eyes what, before 1616, was only a opinion and sympathy. In the second chapter we analyzed the turning of exsperimental philosophy after 1615, from the critical phase to the polemic one. In the third chapter through the historical analysis of the peripatetic’s works, we pointed out the political of Galileo’s philosophy and how Galileo outlined the modernity.

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23

Rebeyrol, Emilie. "Optimisation des signaux et de la charge utile Galileo." Phd thesis, Télécom ParisTech, 2007. http://pastel.archives-ouvertes.fr/pastel-00004315.

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Le système de positionnement Galileo est un nouveau système de navigation par satellite en cours de développement pour l'Union Européenne, qui devrait être opérationnel en 2013. Tout en fournissant un service de positionnement autonome, Galileo sera interopérable avec les systèmes de navigation par satellite déjà existants comme le système américain GPS (Global Positioning System). En effet, un utilisateur pourra, avec un récepteur compatible, obtenir une position quelque soit le système utilisé. De plus, Galileo a pour objectif de garantir la disponibilité de certains services tels que le service commercial (CS) par exemple ou le service public réglementé (PRS). Mais Galileo fournit aussi, avec le service Sécurité de la vie (SOL), un message d'intégrité permettant de déterminer si l'information satellite est fiable, afin de l'utiliser pour des applications critiques telles que le transport aérien, maritime ou terrestre. Afin de fournir une position, une synchronisation et une information d'intégrité précises, en accord avec les besoins des utilisateurs, le système Galileo doit posséder des signaux et une architecture performants. L'étude de la conception de ces signaux, leur génération et leurs performances constitue le coeur de cette thèse. En effet, l'objectif principal de ce travail est l'optimisation de la charge utile et des signaux Galileo afin d'obtenir les meilleures performances possibles du point de vue du récepteur. Une analyse complète du système Galileo, de la charge utile au récepteur est d'abord effectuée. Elle montre que des distorsions peuvent affecter les signaux pendant leur génération, leur propagation et leur traitement dans le récepteur. Ces distorsions, dues aux instabilités d'horloges, aux non-linéarités de l'amplificateur, aux filtrages ou aux trajets multiples (multitrajets), réduisent la performance des signaux, en particulier lors de la poursuite du code ou lors de la poursuite de la phase de la porteuse. Pour éviter ces distorsions ou pour réduire leur impact, les signaux Galileo doivent présenter certaines propriétés, comme une enveloppe constante ou une large bande par exemple. Il est donc important d'analyser ces contraintes pour la conception d'une charge utile et de signaux performants. Une étude est ensuite menée afin de déterminer si les signaux Galileo proposés par la GJU (Galileo Joint Undertaking), en particulier en bande E5 et E1(E1-L1-E2), présentent ces propriétés et ainsi vérifient les contraintes de conception. La modulation Interplex et la modulation ALTBOC (Alternate Binary Offset Carrier) sont les solutions proposées pour multiplexer, respectivement, les signaux E1 et E5. Les expressions théoriques et les performances de ces modulations sont analysées afin de montrer qu'elles transmettent les signaux avec une enveloppe constante permettant de réduire les distorsions dues aux non-linéarités de l'amplificateur. Récemment, de nouvelles formes d'onde ont été proposées pour transmettre le signal " Open Service " de Galileo en bande E1, toujours avec l'objectif d'obtenir de meilleures performances. Ces nouveaux signaux sont basés sur la combinaison linéaire d'un signal BOC(1,1) avec un signal " Binary Coded Symbol (BCS) " ou avec une autre sous porteuse BOC. Ces signaux sont alors appelés Composite BCS (CBCS) ou Composite BOC (CBOC). Ces nouveaux signaux, conçus afin de réduire l'impact des multitrajets sur les performances, sont étudiés tout au long de la chaîne de transmission afin de contrôler s'ils vérifient les contraintes de conception et s'ils peuvent être transmis avec la modulation Interplex. Leurs performances sont aussi évaluées et comparées à celle du signal BOC(1,1), grâce à des observables qui caractérisent les performances en réception. Ces observables sont la fonction d'autocorrélation, la densité spectrale de puissance, le coefficient d'isolation spectrale et l'enveloppe d'erreur due aux trajets multiples. Pour terminer, des simulations permettent d'évaluer l'influence des distorsions dues aux équipements de la charge utile et du récepteur, sur les signaux Galileo et sur leur performance en réception, sont présentées. En particulier, l'influence des horloges, des amplificateurs et des filtres est évaluée grâce notamment au calcul de l'erreur de phase dans la boucle de poursuite du récepteur.

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Chavagnieux, Cédric. "Développement d'un récepteur hybride GPS/GALILEO en environnement réel." Mémoire, École de technologie supérieure, 2007. http://espace.etsmtl.ca/564/1/CHAVAGNIEUX_C%C3%A9dric.pdf.

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Ces travaux sont liés au projet Software Defined Navigator (SDN) du laboratoire LACIME de l'ÉTS. L'objectif est de créer une plate-forme de recherche pour la conception de systèmes de navigation par satellites utilisant les systèmes GPS et Galileo. Le développement d'un récepteur hybride GPS/Galileo dans un environnement réel s'inscrit dans la première phase du projet. Développé dans Matlab-Simulink, le simulateur se compose de deux modules: le module de génération de signaux GPS L1C et Galileo E1, et le récepteur GPS/Galileo. Dans ce rapport, on retrouve la présentation et l'implémentation du module de génération de signaux, comprenant l'ajout d'un générateur de constellation et la prise en compte de trajectoires réalistes. L'architecture du récepteur hybride GPS/Galileo et sa validation en simulation sont présentées par la suite. Finalement, l'utilisation d'un générateur de signaux GPS L1 certifié (le simulateur GSS7700) permet de valider le fonctionnement de la partie GPS du récepteur hybride.

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Chavagnieux, Cédric. "Développement d'un récepteur hybride GPS/GALILEO en environnement réel /." Thèse, Montréal : École de technologie supérieure, 2007. http://proquest.umi.com/pqdweb?did=1459906831&sid=1&Fmt=2&clientId=46962&RQT=309&VName=PQD.

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Thèse (M.Ing) -- École de technologie supérieure, Montréal, 2007.
"Mémoire présenté à l'École de technologie supérieure comme exigence partielle à l'obtention de la maîtrise en génie électrique." CaQMUQET Bibliogr. : f. [176]-178. Également disponible en version électronique. CaQMUQET

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Dion, Arnaud. "Récepteur de navigation reconfigurable pour applications spatiales." Thesis, Toulouse, ISAE, 2014. http://www.theses.fr/2014ESAE0032/document.

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L’orbite d’un satellite autour de la terre est perturbée en permanence par différents facteurs, tels que la variation du champ gravitationnel et la pression du vent solaire. La dérive de la position du satellite peut compromettre la mission, voire mener à une collision ou à une chute dans l’atmosphère. Les opérations de maintien à poste consistent donc à effectuer une mesure précise de la trajectoire du satellite puis à utiliser ses propulseurs pour corriger sa dérive. La solution classique de mesure de position est basée sur des radars au sol. Ce dispositif est couteux et ne permet pas d’avoir la position du satellite en permanence : les corrections de trajectoires se font donc de façon espacées dans le temps.Un système de positionnement et de navigation autonome utilisant les constellations de satellites de navigation, appelées Global Navigation Satellite System (GNSS), permettrait une réduction importante des coûts de conception et de maintenance opérationnelle. Plusieurs études ont été menées en ce sens et les premiers systèmes de navigation, basés sur des récepteurs GPS, voient le jour. Un récepteur en mesure de traiter plusieurs systèmes de navigation, tel que GPS et Galileo, permettrait d’obtenir une meilleure disponibilité de service. En effet, le système Galileo est conçu pour être compatible avec le système GPS,tant en terme de signaux émis que de données de navigation. La connaissance permanente de la position permettrait alors de réaliser un contrôle asservit du maintien à poste.Dans un premier temps, nous avons défini quelles seront les spécifications d’un récepteur spatial multi-mission.En effet, les contraintes pesant sur un tel récepteur sont différentes de celles d’un récepteur situé à la surface de la Terre. L’analyse de ces contraintes, ainsi que des performances demandées à un système de positionnement, est donc nécessaire afin de déterminer les spécifications du futur récepteur. Il existe peu d’études sur le sujet. Certaines d’entre elles sont classées secret industriel, d’autres présentent, à notre avis,un biais d’analyse qui fausse la détermination des spécifications.Nous avons donc modélisé le système : orbites des satellites GNSS et des satellites récepteurs, liaison radiofréquence. Certains paramètres de cette liaison ne sont pas donnés dans les documents de spécifications ou les documents constructeurs. De plus, les données théoriques disponibles ne sont pas toujours pertinentes pour une modélisation réaliste. Nous avons donc dû estimer ces paramètres en utilisant des données disponibles.Le modèle a été ensuite utilisé afin de simuler divers scenarii représentatifs de futures missions. Après avoir défini des critères d’analyse, les spécifications ont été déterminées à partir des résultats des simulations.Le calcul d’une position par un système de navigation par satellite se déroule en trois phases principales.Pour chacune de ces phases, il existe plusieurs algorithmes possibles, présentant des caractéristiques différentes de performance, de taille de circuit ou de charge de calcul. L’essor de nouvelles applications basées sur la navigation entraine également le développement de nouveaux algorithmes adaptés.Nous présentons le principe permettant la détermination d’une position, puis les signaux de navigation GPS et Galileo. A partir de la structure des signaux, nous expliquons les phases de la démodulation et de la localisation. Grâce à l’utilisation des constellations GPS et Galileo, les algorithmes standards permettent d’atteindre les performances nécessaires pour des applications spatiales. Ces algorithmes nécessitent néanmoins d’être adaptés ; ainsi certaines parties ont été conçues spécifiquement. Afin de valider les choix d’algorithmes, et les paramètres liés aux spécifications, nous avons simulés les différentes phases de fonctionnement du récepteur en utilisant des signaux GPS réels.Pour terminer, les retombées et perspectives sont exposées dans la conclusion
The orbit of a satellite around the earth is constantly disturbed by various factors, such as variations in the gravitational field and the solar wind pressure. The drift of the satellite position can compromise the mission, and even lead to a crash or a fall in the atmosphere. The station-keeping operations therefore consist in performing an accurate measurement of the satellite trajectory and then in using its thrusters to correct the drift. The conventional solution is to measure the position with the help of a ground based radar. This solution is expensive and does not allow to have the satellite position permanently: the trajectory corrections are therefore in frequent. A positioning and autonomous navigation system using constellations of navigation satellites, called Global Navigation Satellite System (GNSS), allows a significant reduction in design and operational maintenance costs. Several studies have been conducted in this direction and the first navigation systems based on GPS receivers, are emerging. A receiver capable of processing multiple navigation systems, such as GPS and Galileo, would provide a better service availability. Indeed, Galileo is designed to be compatible with GPS, both in terms of signals and navigation data. Continuous knowledge of the position would then allow a closed loop control of the station keeping. Initially, we defined what the specifications of a multi-mission space receiver are. Indeed, the constraints on such a receiver are different from those for a receiver located on the surface of the Earth. The analysis of these constraints, and the performance required of a positioning system, is necessary to determine the specifications of the future receiver. There are few studies on the subject. Some of them are classified; others have, in our view, an analytical bias that distorts the determination of specifications. So we modeled the system: GNSS and receivers satellite orbits, radio frequency link. Some parameters of this link are not given in the specification or manufacturers documents. Moreover, the available theoretical data are not always relevant for realistic modeling. So we had to assess those parameters using the available data. The model was then used to simulate various scenarios representing future missions. After defining analysis criteria, specifications were determined from the simulation results. Calculating a position of a satellite navigation system involves three main phases. For each phase, there are several possible algorithms, with different performance characteristics, the circuit size or the computation load. The development of new applications based on navigation also drives the development of new adapted algorithms. We present the principle for determining a position, as well as GPS and Galileo navigation signals. From the signal structure, we explain the phases of the demodulation and localization. Through the use of GPS and Galileo constellations, standard algorithms achieve the performance required for space applications. However, these algorithms need to be adapted, thus some parts were specifically designed. In order to validate the choice of algorithms and parameters, we have simulated the various operating phases of the receiver using real GPS signals. Finally, impact and prospects are discussed in the conclusion

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Acurio, Armas Andrea E. "Coevolutionary analysis of the transposon Galileo in the genus Drosophila." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/285742.

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La asociación entre un parásito y un hospedador ofrece una excelente oportunidad para el estudio de tazas de especiación y evolución. La base para dichos estudios sólo puede ser enfocada mediante el análisis de filogenético de la asociación parásito-hospedador. Los elementos transponibles son secuencias cortas de ADN que se comportan como parásitos intragenómicos. Ellos son transmitidos verticalmente a través de las generaciones, aunque la transferencia horizontal ha sido propuesta como un paso esencial en su dinámica evolutiva a largo plazo. Galileo es un miembro de la Superfamilia P de transposones de ADN. Galileo fue inicialmente descubierto en Drosophila buzzatii, en donde es responsable de la generación de tres inversiones cromosómicas y subsecuentemente reportado en especies cercanas y en seis genomas secuenciados de Drosophila. En este estudio se ha ejecutado una búsqueda exhaustiva del transposon Galileo en 234 muestras de 133 especies de los géneros Drosophila, Scaptodrosophila, Scaptomyza and Zaprionus con muestras provenientes de ocho regiones zoo-geográficas. Para detectar Galileo se realizaron búsquedas bioinformáticas y experimentales mediante PCR + clonación de la región más conservada de la transposasa. Galileo fue detectado en 152 muestras de 51 especies de Drosophila de los subgéneros Sophophora, Drosophila y Siphlodora. Simultáneamente, la filogenia de 174 especies de Drosophilidae (que incluye todas las especies en las que se realizó la búsqueda de Galileo) se construyó con secuencias parciales de cuatro genes: SinA, ND2, COI y COII. Los resultados son consistentes con una antigua coevolución de Galileo en el género Drosophila. Galileo ha sido encontrado en especies de los subgéneros Sophophora, Drosophila and Siphlodora, que divergieron hace ca. 40-57 millones de años. Un hecho interesante es que Galileo fue detectado en varias poblaciones del subgénero Sophophora de Asia, en donde se piensa ha tenido su origen el ancestro de dicho subgénero. En comparaciones de ambas filogenias, de las especies y Galileo se han encontrado: 1) ocurrencia discontinua (distribución parcheada) entre 31 grupos de especies, 2) incongruencias entre las topologías de los árboles filogenéticos de las especies hospedadoras y Galileo, 3) en el último caso, la divergencia las secuencias de Galileo fue más pequeña entre los genes de las especies hospedadoras, y 4) una señal biogeográfica en la filogenia de Galileo. Los resultados encontrados en este estudio sugieren que el transposon Galileo estuvo presente en el ancestro común más reciente del subgénero Sophophora. La invasión de Galileo en el subgénero Drosophila y Siphlodora puede ser datada en ca. 40-56 Ma, cuando estos clados se separaron. Dentro de su hospedador, Galileo ha sido mayoritariamente transmitido verticalmente con pérdidas estocásticas y propagaciones horizontales antiguas.
Host-parasite assemblages offer exciting possibilities for the comparative study of rates of speciation and evolution. The basis for such studies can only be approached from a phylogenetic analysis of host-parasite association. Transposable elements are short DNA sequences that behave as intragenomic parasites. They are vertically transmitted through many generations, although horizontal transfer has been proposed as an essential step in their long-term evolutionary dynamics. Galileo is a member of the P superfamily of DNA transposons. It was initially discovered in Drosophila buzzatii, where it is responsible for the generation of three chromosomal inversions, and subsequently reported in closely related species and in six Drosophila genomes sequenced. Here in a thorough search of the Galileo transposon has been carried out in 234 samples of 133 species from the genera Drosophila, Scaptodrosophila, Scaptomyza and Zaprionus. The samples come from eight zoo-geographical regions. In order to detect Galileo, in silico BLAST searches and experimental searches by PCR + cloning of the most conserved region of the TPase were performed. Galileo was unequivocally detected in 152 samples of 51 Drosophila species from the subgenera Sophophora, Drosophila and Siphlodora. Simultaneously, the phylogeny of 174 Drosophilid species (including all taxa in which Galileo was searched) was inferred from partial coding sequences of four genes: SinA, ND2, COI and COII. The results are consistent with an ancient coevolution of Galileo in the genus Drosophila. Galileo has been found in species of the subgenera Sophophora, Drosophila and Siphlodora, that diverged ca. 40-57 million years ago. An interesting fact is that Galileo was detected in several populations of the subgenus Sophophora from Asia, where it is thought the ancestor of Sophophora has its origin. In comparisons of both, the Drosophila species and Galileo transposon phylogenies, it was found: 1) discontinuous occurrence of Galileo across 31 species groups (patchy distribution), 2) incongruence between host and TE tree topologies, 3) in the latter case, divergence between Galileo sequences was smaller than between genes of the host species, and 4) a bio-geographical signal in the Galileo phylogeny. These results found herein suggest that the Galileo transposon was present in the most recent common ancestor of the Sophophora subgenus. The invasion of Galileo in the subgenera Drosophila and Siphlodora could be dated at ca. 40-56 Mya, when this clades split. Inside its host, Galileo has been mostly vertically transmitted with stochastic losses and occasional ancient horizontal spreads.

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Murugan, Deepak. "Design of a Voltage Controlled Oscillator for Galileo/GPS Receiver." Thesis, Linköpings universitet, Institutionen för systemteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76279.

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The main aim of this thesis is to implement a voltage-controlled oscillator for a Galileo/GPS receiver with a center frequency of 1.5 GHz in 150 nm CMOS process. As the designed VCO has to be integrated in a phase locked loop, VCO gain is selected high enough for the PLL to lock even with process variations. A new state of art architecture called double harmonic tuned VCO is selected and designed for this GPS application. It uses a complex combination of inductors and capacitors to reduce phase-noise of the VCO by suppressing second harmonic oscillations in the tail node of VCO. The designed VCO shows significant improvement in phase-noise performance compared to a normal LC tank VCO by reducing phase-noise around 4 dBc/Hz. The VCO has a phase-noise of -128 dBc/Hz at 1 MHz offset from center frequency with a power consumption of 5 mW and a tuning range of about 257 MHz for a 1 V tuning voltage range.

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Guilbert, Alize. "Optimal GPS/GALILEO GBAS methodologies with an application to troposphere." Phd thesis, Toulouse, INPT, 2016. http://oatao.univ-toulouse.fr/16120/1/Guilbert.pdf.

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In the Civil Aviation domain, research activities aim to improve airspace capacity and efficiency whilst meeting stringent safety targets. These goals are met by improving performance of existing services whilst also expanding the services provided through the development of new Navigation Aids. One such developmental axe is the provision of safer, more reliable approach and landing operations in all weather conditions. The Global Navigation Satellite System (GNSS) has been identified as a key technology in providing navigation services to civil aviation users [1] [2] thanks to its global coverage and accuracy. The GNSS concept includes the provision of an integrity monitoring function by an augmentation system to the core constellations. This is needed to meet the required performances which cannot be met by the stand-alone constellations. One of the three augmentation systems developed within civil aviation is the GBAS (Ground Based Augmentation System) and is currently standardized by the ICAO to provide precision approach navigation services down to Cat I using the GPS or GLONASS constellations [3]. Studies on-going with the objective to extend the GBAS concept to support Cat II/III precision approach operations with GPS L1 C/A, however some difficulties have arisen regarding ionospheric monitoring. With the deployment of Galileo and Beidou alongside the modernization of GPS and GLONASS, it is envisaged that the GNSS future will be multi-constellation (MC) and multi-frequency (MF). European research activities have focused on the use of GPS and Galileo. The MC/MF GBAS concept should lead to many improvements such as a better modelling of atmospheric effects but several challenges must be resolved before the potential benefits may be realized. Indeed, this PhD has addressed two key topics relating to GBAS, the provision of corrections data within the MC/MF GBAS concept and the impact of tropospheric biases on both the SC/SF and MC/MF GBAS concepts. Due to the tight constraints on GBAS ground to air communications link, the VDB unit, a novel approach is needed. One of the proposals discussed in the PhD project for an updated GBAS VDB message structure is to separate message types for corrections with different transmission rates. Then, this PhD argues that atmospheric modelling with regards to the troposphere has been neglected in light of the ionospheric monitoring difficulties and must be revisited for both nominal and anomalous scenarios. The thesis focuses on how to compute the worst case differential tropospheric delay offline in order to characterize the threat model before extending previous work on bounding this threat in order to protect the airborne GBAS user. In the scope of MC/MF GBAS development, an alternative approach was needed. Therefore, in this PhD project, Numerical Weather Models (NWMs) are used to assess fully the worst case horizontal component of the troposphere. An innovative worst case horizontal tropospheric gradient search methodology is used to determine the induced ranging biases impacting aircraft performing Cat II/III precision approaches with GBAS. This provides as an output a worst case bias as a function of elevation for two European regions.The vertical component is also modelled by statistical analysis by comparing the truth data to the GBAS standardized model for vertical tropospheric correction up to the height of the aircraft. A model of the total uncorrected differential bias is generated which must be incorporated within the nominal GBAS protection levels. In order to bound the impact of the troposphere on the positioning error and by maintaining the goal of low data transmission, different solutions have been developed which remain conservative by assuming that ranging biases conspire in the worst possible way. Through these techniques, it has been shown that a minimum of 3 parameters may be used to characterize a region’s model.

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Ehm, Henning J. "Galileo/GPS single shot radio receiver architectures for mobile stations /." Tönning [u.a.] : Der Andere Verlag, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016401619&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Dodge, Michael. "Global navigation satellite systems (GNSS) and the GPS-Galileo agreement." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=106582.

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The law of global navigation satellite systems is a nascent, yet growing academic field. The subject matter it studies, GNSS, has been and is becoming ever-more important in the modern world, both for transportation, as well as for commerce. Indeed, globalization has seen billions of euros in trade associated with both nautical and aviation shipping, and this trend is likely to grow larger with the passage of time. Additionally, the nations of the world are fast realizing the potential of GNSS to make their aviation industries more robust and efficient, with integration of GNSS into air traffic management certain to increase the number of aircraft in flight at any given time, decrease the separation between such craft, and allow for safer takeoffs and landings, as well as improve flight in areas whose terrain has traditionally been quite challenging for contemporary navigational aids. In 2004, the United States and the European Community signed an Agreement intended to ensure radio compatibility and interoperability between the U.S. Global Positioning System and the upcoming Galileo GNSS. This collaboration should enable continued and rapid growth of commerce and navigation improvements to aviation, but several of its provisions are poorly, if at all, defined. As a result, this thesis attempts to elaborate the nature and meaning behind the 2004 Agreement, while also serving to illuminate current legal theories concerning the liability regimes that accompany GNSS.
Le droit des systèmes de positionnement par satellites (GNSS) est une nouvelle matière académique qui est en train de se développer. Le GNSS devient de plus en plus important dans le monde d'aujourd'hui tant pour le transport que pour le commerce. La mondialisation a contribué à la croissance du transport des biens par voies maritime et aérienne, et cette tendance ne pourrait qu'augmenter. Les pays du monde se rendent de plus en plus compte des possibilités d'usage du GNSS pour renforcer leurs industries aériennes en employant le GNSS dans la gestion du trafic aérien afin d'augmenter la capacité du ciel en réduisant la distance séparant les aéronefs, de rendre plus sécuritaires les décollages et les atterrissages, et de faciliter l'aviation dans des zones où la technologie contemporaine a prouvé insuffisante. En 2004, les États-Unis et l'Union Européenne ont signé un accord qui assure la radio-compatibilité et l'interopérabilité du système GNSS américain et son équivalent européen, Galileo. Cette collaboration devrait contribuer à une croissance continue du commerce et de l'aviation. Par contre, plusieurs dispositions dans l'accord sont mal ou pas du tout définies. Cette mémoire cherche donc à élaborer la nature ainsi que le sens à donner à l'accord de 2004, tout en exposant les théories juridiques contemporaines concernant la responsabilité juridique pour GNSS.

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Farah, Ashraf Mohamed Ahmed. "GPS/Galileo simulation for reduced dynamic LEO satellite orbit determination." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/11288/.

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Global Navigation Satellite Systems (GNSS) have an endless number of applications in industry, science, military, transportation and recreation & sports. Two systems are currently in operation namely GPS (the USA Global Positioning System) and GLONASS (the Russian GLObal NAvigation Satellite System), and a third is planned, the European satellite navigation system GALILEO. The potential performance improvements achievable through combining these systems could be significant and expectations are high. Computer software can be used to simulate the overall process of GNSS (signal transmission and reception) and produce realistic simulated GNSS measurements. Using such simulated measurements, current and future GNSS systems and possible new applications of GNSS can be investigated. Thus data simulation is the perfect research tool in GNSS fields. Oceanography, is one application of GNSS, which requires position determination with a high accuracy. LEO satellites are used to measure the precise height of the sea surface for studying the dynamics of the world's oceans. Achieving maximum benefit from the altimetric data collected by LEO satellites requires a radial orbit accuracy of 10 cm, or better. It is in determining this orbit where GNSS may be utilised. GPS already delivers high quality position information for LEO satellite orbits such as Topex/Poseidon (1992- present). However LEO satellite orbits determination can still benefit from using GPS combined with GALILEO as there will be more visible satellites and a higher quality of measurements. Investigation of LEO satellite orbit determination using GPS or GALILEO or both systems requires GPS and GALILEO measurements. Due to the lack of real GALILEO measurements, as the system is still in development, the simulation of GPS and GALILEO measurements is required. In order to generate realistic simulated GPS and GALILEO data, the errors, which predominate in GNSS measurements, must be accurately modelled. During this research, it has been shown that it is possible to generate realistic simulated GPS data through the more realistic simulation of the ionospheric, tropospheric and multipath delays. Models with a high spatial resolution have been implemented to simulate the real behaviour of the ionosphere and troposphere. The behaviour of the resulting simulated GPS data is shown to follow the behaviour of real GPS data with a strong agreement. It has also been possible to generate GALILEO simulated data through modifying the simulation software using the GALELEO Design technical specifications. The potential impact of using GPS and GALILEO on LEO satellite orbit determination could be investigated on Topex/Poseidon mission which real GPS data was available from the beginning of this study. The performance of GPS, GALILEO, combined GPS/GALILEO and combined GPS-modernised/GALELEO constellations have been investigated in relation to the reduced dynamic orbit determination of the LEO satellite Topex/Poseidon. It can be concluded that the GALILEO constellation will provide high quality real time LEO satellite orbits compared with GPS. GALELEO constellation will provide slightly better quality real time LEO satellite orbits over the combined GPS-present/GALELEO constellation. However the best quality real time LEO satellite orbits will result from the combined GPS-modernised/GALILEO constellation.

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Temple, Thomas J. (Thomas John). "Autonomous error bounding of position estimates from GPS and Galileo." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37884.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.
Includes bibliographical references (p. 79-81).
In safety-of-life applications of satellite-based navigation, such as the guided approach and landing of an aircraft, the most important question is whether the navigation error is tolerable. Although differentially corrected GPS is accurate enough for the task most of the time, anomalous measurement errors can create situations where the navigation error is intolerably large. Detection of such situations is referred to as integrity monitoring. Due to the non:stationary nature of the error sources, it is impossible to predetermine an adequate error-bound with the required confidence. Since the errors at the airplane can be different from the errors at reference stations, integrity can't be assured by ground monitoring. It is therefore necessary for the receiver on the airplane to autonomously assess the integrity of the position estimate in real-time. In the presence of multiple errors it is possible for a set of measurements to remain self-consistent despite containing errors. This is the primary reason why GPS has been unable to provide adequate integrity for aircraft approach. When the Galileo system become operational, there will be many more independent measurements. The more measurements that are available, the more unlikely it becomes that the errors happen to be self-consistent by chance. This thesis will quantify this relationship.
(CONT.) In particular, we determine the maximum level of navigation error at a given probability as a function of the redundancy and consistency of the measurements. Rather than approach this problem with statistical tests in mind, we approach this as a machine learning problem in which we empirically determine an optimal mapping from the measurements to an error bound. In so doing we will examine a broader class of tests than has been considered before. With a sufficiently large and demanding training data, this approach provides error-bounding functions that meet even the strictest integrity requirements of precision approaches. We determine the optimal error-bounding function and show that in a GPS + Galileo constellation, it can meet the requirements of Category I, II and III precision approach-a feat that has proven difficult for GPS alone. This function is shown to underestimate the level of error at a rate of less than 10-7 per snapshot regardless of the pseudorange error distribution. This corresponds to a rate of missed detection of less than 10-9 for all approach categorizations. At the same time, in a 54 satellite constellation, the level of availability for Category I precision approaches availability exceeds 99.999%. For Category II and III precision approaches, it can provide availability exceeding 99.9% with either a 60 satellite constellation, or with a modest improvement over existing LAAS corrections.
by Thomas J. Temple.
S.M.

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Toluc, Ahmet Bayram. "Multi-GNSS Precise Point Positioning Using GPS, GLONASS and Galileo." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471490165.

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Ortiz, Centeno Modesto Abundio. "La nueva concepción de objetividad ontológica en la ciencia galileana." Master's thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/6525.

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Se toma en cuenta que en la investigación de la naturaleza se supone el postulado denominado “realismo ontológico” que define el enfoque de la investigación fundamentalmente como realista. Se muestra que en las investigaciones de la naturaleza realizadas por Galileo subyace de hecho el postulado del realismo ontológico; por ello y por el hecho de que tal postulado, por sus raíces presocráticas, presenta un carácter materialista, el enfoque de la actividad científica galileana fue de hecho realista materialista. El postulado del realismo ontológico materialista, o mecanicista en sentido lato, señala que hay un mundo exterior que existe independientemente del sujeto cognoscente y que es material. Este postulado supone a su vez un concepto general de objetividad ontológica mecanicista según el cual la objetividad es una condición de la materia en sí misma y no lo pone el sujeto cognoscente. Pero, para hacer frente al racionalismo esencialista que identifica propiedades primarias con entes, se distingue dos sentidos o dimensiones diferentes de objetividad ontológica: dimensión propia y dimensión derivada. Esta distinción es paralela a dos niveles de realidad con estatus ontológico distinto: elemental (primario) y compuesto (secundario). En dimensión propia la objetividad se aplica en el dominio de los elementos a los que se reduce la materia corpórea en última instancia y algunos de cuyos rasgos básicos, en la versión final galileana, son: indivisibles y no extensos, tal vez sin consistencia alguna, análogos a puntos geométricos, plenos, no vacíos. De elementos con tales condiciones se dice, entonces, que son objetivos en sentido ontológico propio. La dimensión derivada del concepto de objetividad ontológica se aplica en el dominio de las propiedades de objetos materiales, entre las que Galileo considera la forma, cantidad de materia y movimiento mecánico fundamentalmente; de tales propiedades se dice que son objetivas en sentido ontológico derivado. En ninguna de las dos dimensiones se ha encontrado que Galileo haya salido del esquema mecanicista. Cuando tuvo la necesidad de fundamentar la matematización de la naturaleza (posibilidad de la física matemática) estimó que no era necesario salir del marco ontológico mecanicista, sino que consideró suficiente una concepción realista de las teorías de tipo semántico. En tal intención, postuló la existencia de “propiedades matemáticas” en los cuerpos (propiedades mecánicas o primarias) y consideró un puente semántico entre estas propiedades materiales (no conceptuales) con estatuto ontológico derivado y los conceptos e ideas de la ciencia matemática, estos últimos son así objetos conceptuales con significado fáctico. De modo que no fue necesario postular en la naturaleza material la existencia de entidades ideales (objetos matemáticos) con estatus ontológico primario. Se complementa este estudio con una breve consideración semántica intuitiva orientada a enfatizar el carácter complejo y sistémico del concepto de objetividad ontológica.
Tesis

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Lollini, Emanuele. "Modello termico dello spacecraft Galileo e valutazione delle accelerazioni non gravitazionali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18515/.

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Il seguente elaborato di tesi ha lo scopo di valutare le accelerazioni non gravitazionali dello spacecraft Galileo causate dalla radiazione termica emessa principalmente dai due RTG di cui è dotato il veicolo. Verranno presentate brevemente la missione Galileo e le caratteristiche del veicolo spaziale che sarà protagonista di questo studio, seguirà una trattazione della teoria delle radiazioni e infine si procederà con lo sviluppo del modello termico dello spacecraft. Le dimensioni ufficiali di Galileo sono state ricavate dalla riproduzione pubblicata in NASA 3D Resources dal Jet Propulsion Laboratory, grazie alla quale è stato possibile generarne una geometria semplificata tramite Solidworks. Per lo studio della radiazione termica anisotropa ci si è serviti del software COMSOL multiphysics. Oltre alla configurazione che prevede gli RTG come unica fonte di calore del sistema, sono state considerate altre soluzioni come la presenza della radiazione solare e il calore generato dall’energia elettrica utilizzata dalle apparecchiature contenute nel BUS. Grazie a questo modello è possibile generare grafici che mostrano esplicitamente come avviene la propagazione della radiazione termica e calcolare accuratamente la spinta provocata da questa radiazione anisotropa.

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Garcia, Peña Axel Javier. "Optimization of demodulation performance of the GPS and GALILEO navigation messages." Phd thesis, Toulouse, INPT, 2010. http://oatao.univ-toulouse.fr/12022/1/garcia_pena_partie_1_sur_2.pdf.

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The demodulation performance achieved by any of the existing GPS signals, L1 C/A, L2C or L5, is satisfactory in open environments where the available C/N0 is quite high. However, in indoor/urban environments, the C/N0 level of the received signal is often very low and suffers fast variations which can further affect the GNSS messages demodulation. Therefore, since the mass-market applications being designed nowadays are aimed at these environments, it is necessary to study and to search alternative demodulation/decoding methods which improve the GNSS messages demodulation performance in these environments. Moreover, new GNSS signals recently developed, such as GPS L1C and GALILEO E1, must also be considered. These signals aim at providing satellite navigation positioning service in any kind of environment, giving special attention to indoor and urban environments. Therefore, the demodulation performances of the new GNSS signals as they are defined in the current public documents is also analysed. Moreover, new GALILEO E1 message structures are proposed and analysed in order to optimize the demodulation performance as well as the quantity of broadcasted information. Therefore, the main goal of this dissertation is to analyse and to improve the demodulation performance of the current open GNSS signals, specifically in indoor and urban environments, and to propose new navigation message structures for GALILEO E1. A detailed structure of this dissertation sections is given next. First, the subject of this thesis is introduced, original contributions are highlighted, and the outline of the report is presented. Second, this dissertation begins by a description of the current structure of the different analysed GNSS signals, paying special attention to the navigation message structure, implemented channel code and their decoding techniques. In the third section, two types of transmission channel models are presented for two different types of environments. On one hand, an AWGN channel is used to model the signal transmission in an open environments. On the other hand, the choice of a specific mobile channel, the Perez-Fontan channel model, is chosen to model the signal transmission in an urban environment. In the fourth section, a tentative to make a binary prediction of the broadcasted satellite ephemeris of the GPS L1 C/A navigation message is presented. The prediction is attempted using the GPS L1 C/A almanacs data, a long term orbital prediction program provided by TAS-F, and some signal processing methods: spectral estimation, the PRONY method, and a neural network. In the fifth section, improvements to the GPS L2C and GPS L5 navigation message demodulation performance are brought by using their channel codes in a non-traditional way. Two methods are inspected. The first method consists in sharing information between the message inner and outer channel codes in order to correct more received words. The second method consists in using the ephemeris data probabilities in order to improve the traditional Viterbi decoding. In the sixth section, the GPS L1C and GALILEO E1 Open Service demodulation performance is analysed in different environments. First, a brief study of the structure of both signals to determine the received C/N0 in an AWGN channel is presented. Second, their demodulation performance is analysed through simulations in different environments, with different receiver speeds and signal carrier phase estimation techniques.

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Sauriol, Bruno. "Mise en oeuvre en temps réel d'un récepteur hybride GPS-GALILEO." Mémoire, École de technologie supérieure, 2008. http://espace.etsmtl.ca/103/1/SAURIOL_Bruno.pdf.

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Le début du 21e siècle marque un tournant au niveau de la radionavigation par satellite. Parmi les événements importants, mentionnons l'avènement de Galileo, le tout nouveau système de positionnement de l'Union européenne, ainsi que la modernisation du GPS {Global Positioning System) des États-Unis. On prévoit que ces systèmes, regroupés sous l'acronyme GNSS {Global Navigation Satellite System), mettront à la disposition des utilisateurs civils une très grande quantité de signaux vers les années 2015, ceci permettant un positionnement d'une précision et d'une fiabilité sans précédent. Or, tout ce potentiel ne sera obtenu que par l'intégration des signaux GNSS, une tâche pouvant s'avérer très complexe compte tenu des technologies limitées de recherche et de développement (R&D) actuellement employées par l'industrie. Ce mémoire présente la mise en oeuvre en temps réel d'un récepteur de navigation par satellite GNSS hybride (GPS et Galileo). Ce projet, basé sur un FPGA {Field-Programmable Gâte Array), constitue une avance technologique face aux procédés actuellement employés par l'industrie, qui sont coûteux et peu flexibles. Ceci pennettrait donc d'offrir une solution intéressante aux problèmes d'intégration des signaux GNSS. Le récepteur de navigation a été développé afin de démoduler les signaux GPS et Galileo en bande de fréquence Ll (1575,42 MHz). L'architecture système demeure toutefois très flexible et permettrait bientôt de démoduler des signaux en bande L2 (1227,6 MHz) et L5 (1176,45 MHz), par exemple. Le récepteur a été mis en oeuvre via l'élaborafion de trois principales sections, soit la tête radiofréquence (RF), les canaux de démodulation en fréquence intermédiaire (IF) et la solufion de navigation en bande de base. L'architecture, principalement numérique, a été judicieusement développée de manière à permettre l'intégration de plus de 50 canaux de démodulation au sein d'un même FPGA. De plus, l'utilisation d'un ordinateur personnel (PC) afin de calculer la solufion de navigation a permis d'obtenir des performances encore jamais égalées, permettant une fréquence de mise à jour de la posifion de 1 kHz en temps réel. Le récepteur développé a été validé de plusieurs façons, que ce soit par simulation en temps réel à l'aide d'un simulateur de constellation GNSS, ou encore directement à l'extérieur grâce à de vrais signaux GPS et Galileo. Les performances du récepteur ont aussi été étudiées, ce qui a permis de déterminer une précision de 2,2 m RMS horizontalement et de 4,5 m RMS verticalement au niveau du positionnement à l'aide du GPS seulement. De plus, un temps de démarrage de moins de 16 s a pu être mesuré ainsi qu'une capacité de poursuivre les signaux jusqu'à un ratio C/No de 30 dB Hz. Or, toutes ces caractéristiques sont similaires aux récepteurs de navigation que l'on retrouve présentement sur le marché, ce qui indique un très bon fonctionnement pour un premier prototype.

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Andries, Stephanie. "The Global Navigation Satellite System (GNSS) and the European Galileo program /." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30283.

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The Global Navigation Satellite System (GNSS) is the main element of the CNS/ATM system elaborated by the International Civil Aviation Organization (ICAO).
The US GPS and Russian GLONASS are the two existing systems. Both of them were created by the military.
Europe is currently developing a civil navigation satellite system: Galileo.
This thesis will present some legal issues of the GNSS discussed in the framework of ICAO: sovereignty of States, universal accessibility, continuity and quality of the service, cost recovery and financing, certification and liability.
It will also present some legal issues due to the creation of the European Galileo program. The financing, organizational framework, certification and liability will be examined. Finally, ICAO's Charter on the Rights and Obligations of States Relating to GNSS Services will be considered.

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Sauriol, Bruno. "Mise en oeuvre en temps réel d'un récepteur hybride GPS-GALILEO /." Thèse, Montréal : École de technologie supérieure, 2008. http://proquest.umi.com/pqdweb?did=1472139201&sid=6&Fmt=2&clientId=46962&RQT=309&VName=PQD.

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Thèse (M. Ing.) -- École de technologie supérieure, Montréal, 2008.
"par Sauriol, Bruno" -- p. de t. "Mémoire présenté à l'École de technologie supérieure comme exigence partielle à l'obtention de la maîtrise en génie électrique." CaQMUQET CaQMUQET Bibliogr. : f. [302]-308. Également disponible en version électronique. CaQMUQET

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Kemeny, Maximilian Alexander. "“A Certain Correspondence”: The Unification of Motion from Galileo to Huygens." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15733.

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In this work, I focus on one of Galileo's concepts which was neither mathematically nor empirically derived, but instead based on a fundamental intuition regarding the nature of motion: that all mechanical phenomena can be treated in the same way, using the same mathematical and conceptual apparatus. This was Galileo's concept of 'correspondence', and I follow it from its origins at the turn of the 17th century through Thomas Harriot, Marin Mersenne and ultimately to Christiaan Huygens. At the centre of the concept of correspondence was that phenomena which looked similar really were the same; they were separate instances of the same fundamental processes. Hanging chains and projectile trajectories did not form the same curve by coincidence; they formed the same curve because both were produced by the same competition between vertical and horizontal tendencies. Correspondences were one of the major motivating and legitimising factors behind both Galileo and Huygens' desire to treat all of nature mathematically. This conceptual structure justified their treatment of all of mechanics as mathematically the same. Harriot and Mersenne's roles in this story are to show how contemporaries of Galileo could approach the same topic in drastically different ways. Unlike Huygens, neither Harriot nor Mersenne understood the concept of correspondences. While Galileo and Huygens relied crucially on correspondences to understand natural phenomena, both Harriot and Mersenne were able to achieve many important results in mechanics without it. This work is the biography of a concept; one that is contingent, constructed, frequently fruitful but not a historical or scientific necessity.

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Rezende, Evaldo Pereira de. "A noção de inércia em Galileu Galilei." reponame:Repositório Institucional da UnB, 2018. http://repositorio.unb.br/handle/10482/33843.

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Dissertação (mestrado)—Universidade de Brasília,Instituto de Ciências Humanas, Programa de Pós-Graduação em Filosofia, 2018.
O presente trabalho visa analisar o desenvolvimento da noção de inércia em Galileu, tratando-se, portanto, de uma investigação que remonta às origens históricas para, então, realizar análises filosóficas. Dessa maneira, busca-se compreender as concepções aristotélicas acerca do movimento, imprescindíveis para que se possa refletir sobre a relação entre movimento e causalidade. Na sequência, procura-se apresentar os principais pensadores posteriores a Aristóteles cujas ideias contribuíram para o desenvolvimento científico que possibilitou a revolução copernicana e, consequentemente, a concepção galileana de inércia. Os escritos principais de Galileu são analisados, nomeadamente o Diálogo sobre os dois máximos sistemas do mundo e os Discorsi, obras nas quais o pesquisador italiano desenvolve de forma mais acurada a sua visão concernente ao movimento inercial. Por fim, apresenta-se uma discussão contemporânea relativa ao tema, a saber, se Galileu teria defendido uma inércia linear ou circular.
The present work aims to analyze the development of the notion of inertia in Galileo, dealing, therefore, with a investigation that goes back to historical origins to then carry out philosophical analysis. In this way, it seeks out to understand the Aristotelian conceptions concerning movement, which are indispensable so that we can reflect about the relationship between movement and causality. In the sequence, one looks for to present the main thinkers later to Aristotle whose ideas contributed for the scientific development that made possible the Copernican revolution and, consequently, the Galilean conception of inertia. We analyze the main writings of Galileo, namely the Dialogue Concerning the Two Chief World Systems and the Discorsi, works in which the Italian researcher develops more accurately his vision concerning the inertial movement. Lastly, it presents a contemporary discussion on the subject, namely whether Galileo would have defended a linear or a conception of circular inertia.

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Loizou, John. "An assessment of the autonomous integrity monitoring performance of a combined GPS/Galileo Satellite Navigation System, and its impact on the case for the development of Galileo." Thesis, Cranfield University, 2004. http://hdl.handle.net/1826/1604.

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In 1999 Europe, through the European Commission and the European Space Agency, began detailed definition of a second generation Global Navigation Satellite System (GNSS). This GNSS development programme, known as “Galileo”, was intended to both complement and compete against the existing US Global Positioning System (GPS). Unlike GPS, Galileo is intended to be privately financed, following the initial development investment from the EC and ESA, which implies that Galileo should provide some revenue-earning services. From its earliest inception, the basis of these services has been assumed to be through the provision of Signal Integrity through an Integrity Flag broadcast through the Galileo system– a service which GPS cannot provide without some external system augmentation. This thesis undertakes a critical evaluation of the value of this integrity system in Galileo. This thesis has two parts. The first demonstrates that the conditions required to attract adequate private finance to the Galileo programme are incompatible with the system architecture derived from the early Galileo system studies and taken forward into the system early deployment phase, which includes an Integrity system within Galileo. The second part of this thesis aims to demonstrate that receivers which can combine the signals from GPS and Galileo may offer a free Integrity service which meet the needs of the majority of users, possibly up to the standards required for aviation precision approach. A novel Receiver Autonomous Integrity Monitoring (RAIM) technique is described, using an Errors in Variables/Total Least Squares approach to the detection of inconsistencies in an over-determined set of GNSS signal measurements. The mathematical basis for this technique is presented, along with results which compare the simulated performance of receivers using this algorithm against the expected performance of Galileo’s internal integrity determination system.

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Delgado, Héctor Manuel. "Indivisibles, correspondances et controverses : Cavalieri, Galilée, Toricelli, Guldin." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAP002.

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Santos, Max Luiz de Oliveira. "Experimento de Galileu do plano inclinado em sala de aula." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/4461.

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Made available in DSpace on 2016-06-02T20:02:55Z (GMT). No. of bitstreams: 1 6218.pdf: 2066679 bytes, checksum: a483fcd437c369b1bdc99a248f67b970 (MD5) Previous issue date: 2014-06-14
This work aims to make a suited reconstruction from the classic experiment of the inclined plane, attributed to Galileo Galilei. The intention is to apply it to high school classes, claiming that it might motivate these students to learn concepts related to physics, and should be able to better understand the subjective nature of what is behind the science and its construction process. It is intended to perform the experiment and guide the activities in order that the activities that students can better understand scientific knowledge as a result of human construction, as well as its inherent limitations, realizing that the science development is based on model making and experimentation, among others, which can be modified along the time. The discussion and investigation of the assumptions made by the great physicist, in the elaboration of the theory of falling bodies, and their validity, may result in rich discussions of scientific development. Students may discuss the possibility of adoption and acceptance of misconceptions in science, and what implications these have for the development of scientific theories. The work analyzes the measurement of time of ball bearings on the inclined plane, evaluating the primitive methods that Galileo could have used to reach its conclusions regarding this type of movement. The dissertation also approaches modern methods, as for example, the measurements of falling objects using a tape recorder of a microcomputer, and finally both time measurement procedures are discussing emphasizing historical and modern discussion of both forms, comparing historical and modern aspects in the development of science. Performed activities, finalize the work with the results of the project and its completion, prospects of continuity, assessing the feasibility of its use as an educational product that can serve as a tool in the process of teaching and learning in high school and used by other teachers in other contexts.
Este trabalho objetiva fazer uma reprodução adaptada do experimento clássico do plano inclinado, atribuído a Galileu Galilei. A intenção é a criação de situações de aprendizagem para serem aplicadas em turmas do ensino médio, pretendendo que as mesmas possam vir a ser um elemento motivador para que estes alunos aprendam conceitos ligados à física, bem como tenham condições de melhor perceber o caráter subjetivo que existe por trás da ciência e do seu processo de construção. Pretende-se com a realização do experimento, e com o direcionamento dado às atividades, que os estudantes possam melhor visualizar o conhecimento científico como fruto de uma construção humana, bem como suas limitações intrínsecas, percebendo que este se solidifica baseado na construção de modelos e hipóteses, que são modificados com o decorrer do tempo. A discussão e averiguação das hipóteses feitas pelo grande físico, na elaboração da teoria da queda dos corpos, bem como a validade das mesmas, poderá ser fruto de ricas discussões sobre o desenvolvimento científico. Os alunos poderão discutir sobre a possibilidade da adoção e aceitação de ideias equivocadas na ciência e as implicações que as mesmas teriam para a elaboração das teorias científicas. O trabalho pretende analisar a medição dos tempos de rolamentos de esferas sobre o plano inclinado, avaliando os métodos que Galileu poderia ter utilizado para efetuá-los e suas conclusões a respeito deste tipo de movimento, bem como fazer uma releitura apresentando métodos mais modernos, como por exemplo, a medição destes tempos com o gravador de som de um microcomputador, e a posterior discussão sobre ambas as formas, confrontando aspectos históricos e modernos na elaboração da ciência. Aplicadas as atividades, finalizaremos o trabalho com os resultados do projeto, e sua conclusão, perspectivas de continuidade, avaliando a viabilidade de sua utilização como um produto educacional que possa servir como ferramenta no processo de ensino aprendizagem em nível médio e utilizado por outros professores em outros contextos.

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Rey-Ubago, Beatriz del. "The emerging GNSS : Galileo, the European alternative to the Global Positioning System." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=78212.

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The Global Satellite Navigation System (GNSS), the core of the International Civil Aviation Organization (ICAO) Communication, Navigation, Surveillance/Air Traffic Management concept is capable of supporting future aviation needs. The implementation of this revolutionary technology however remains overshadowed by a series of complex institutional and legal issues. The extraterritorial control and ownership of existing GNSS systems coupled with the dual character of this technology poses a serious threat to the concept of national sovereignty as traditionally understood. This is further aggravated by the fact that there exists only one de facto GNSS signal provider, thus placed in a position to impose its own conditions without reference to the requirements of the rest of the world.
In an attempt to secure both European political independence and a fair share in the global GNSS market Europe has decided to play an active role by launching Galileo, an autonomous global constellation under the control of civil authorities scheduled to be operational by 2008.
The present thesis analyses the desirability of a suitable legal and institutional GNSS framework to achieve universal acceptance of the GNSS. However, in the context of the present status quo it is unrealistic to expect that the only GNSS signal provider surrender its nationally procured system under the umbrella of an international instrument. National security concerns and industrial policy goals underlie this tendency. The present situation may turn different when the incumbent GPS faces the competition of Galileo, an alternative civil system willing to offer firm legal guarantees of service performance albeit in exchange for a fee. The entire viability of this theory remains however dependent upon the European capability of defining a successful business case for Galileo.

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Lau, Ki Yuen Lawrence. "Phase multipath modelling and mitigation in multiple frequency GPS and Galileo positioning." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1445732/.

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Multipath is the main error source in short- to medium-baseline GNSS (Global Navigation Satellite System) relative positioning. So, in order to achieve the highest possible accuracy, multipath errors must be modelled and/or mitigated. A new era in GNSS positioning is on the horizon. GPS modernisation is being undertaken, which will provide an unencrypted civil signal (L2C) on the L2 frequency and the signal power of the L2 signal will be increased. Also an additional signal, the so-called L5, will be available on GPS Block IIF satellites scheduled for launch beginning in mid- 2006. Furthermore, the European GNSS, named Galileo, is being developed to provide four carrier frequencies and its Full Operational Capability (FOC) is scheduled to be in 2008, but more likely in 2010. This study identifies and models the factors causing phase multipath errors and investigates some possible phase multipath mitigation techniques using the multiple frequency data that modernised GPS and Galileo will offer. A GNSS data simulator has been developed to generate multipath contaminated data using a phase multipath model based on ray tracing. All known geometrical and physical factors have been taken into account and are described in detail. The model has been validated with real data collected in two experiments with reflectors of different materials. A GNSS data processor has been developed for this validation and for subsequent analyses. The results show good agreement (i.e. similar amplitude and frequency) with real multipath from a steel panel (planar reflector) and fairly good agreement (i.e. similar amplitude with slight different frequency) with real multipath from a lake (dynamic irregular reflector). They show that the multipath model has the potential to correct phase multipath errors in cases where the exact geometry of the reflection process and the nature of the reflector are known. Some of the characteristics of phase multipath and the sensitivities of simulated GNSS measurements to the factors causing multipath are investigated and described. Multipath mitigation through averaging based on the least squares process and standard outlier detection technique using multiple frequency GPS, Galileo, and integrated GPS and Galileo data have been investigated. Since multiple frequency GPS and Galileo data are not yet available, all data has been generated by the GNSS data simulator described in the foregoing. It was found that standard outlier detection techniques were not sufficiently robust to tackle the frequency-dependent multipath errors because they could not handle the worst case scenario when multiple frequency multipath errors from a particular satellite were all in-phase. Therefore a cocktail multiple outlier detection algorithm has been proposed and tested. Results show that a combination of more satellites, more frequencies and the cocktail multiple outlier algorithm can substantially mitigate multipath errors and so improve positioning accuracy.

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Leksell, Torbjörn. "A Comparison of Smartphone GPSL1 and Galileo E1-B/C Spoofing Resilience." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292950.

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Location-based services have grown in importance as smartphones, and location-based applications have become an integral part of everyday life. While Global Navigation Satellite Systems (GNSSs) provide the most accurate position determination, open service GNSS signals remain unprotected and susceptible to spoofing attacks. Previous work within the domain highlighted this issue, with many smartphone receivers shown susceptible to GPS L1 spoofing, suggesting that their resilience experiments should be extended to include other GNSS signals in the future. Given that multi-GNSS receivers now have become the norm in smartphones, this thesis investigates whether smartphone GNSS receiver spoofing resilience depends on the type of signal; by conducting a series of comparative spoofing experiments involving GPS L1 and Galileo E1-B/C signals. To conduct the experiments, we developed a Galileo E1-B/C signal simulator that, together with the open-source GPS-SDR-SIM signal simulator, was the basis for conducting a series of experiments designed to identify the potential presence of anti-spoofing measures. The result of our experiments indicates that smartphone multi-GNSS receivers were significantly more resilient towards Galileo E1-B/C spoofing attacks, often accepting GPS L1 signals with significant position, time, and data errors, while refusing to accept corresponding Galileo E1-B/C signals. While we never observed cases of E1-B/C signals being accepted while rejecting GPS L1 signals, external factors limited the scope of the investigation and do not allow a generalized conclusion. As such, to deepen our understanding of these issues and how they relate to the development of anti-spoofing measures and trust in different signals, it is essential to extend this research to include more devices and other GNSS signals.
Positionstjänster har växt i betydelse allteftersom smarttelefoner och positionsapplikationer har blivit en integral del av våran vardag. Även om satellitpositionering utger det mest precisa och vedertagna positionsbestämningen av tillgängliga positionstjänser så är de publika satellitnavigeringssignalarna oskyddade och sårbara för förfalskningsattacker. Tidigare forskning inom området har evaluerat dessa sårbarheter och visat att ett betydande antal smarttelefoner var sårbara för GPS-L1 förfalskningsattacker och att denna forskning borde utökas i framtiden allteftersom satellitnavigeringsmottagare med förmåga att mottaga olika satellitsignaler integreras i smarttelefoner. Givet att en majoritet av nya smarttelefoner nu integrerar denna typ av mottagare så utvärderar detta arbete hur sårbarheten mot förfalskningsattacker beror på typ av satellitsignal genom en komparativ jämförelse av sårbarhet mellan GPS-L1 och den nyare Galileo E1-B/C signalen. För att genomföra utvärderingen så utvecklade vi en Galileo E1-B/C signalsimulator som tillsammans med GPS-L1 signalsimulatorn (GPS-SDR-SIM) utgjorde grunden för en serie av experiment designade för att identifiera och utvärdera sårbarheter och potentiella motåtgärder i smarttelefoner. Våra resultat indikerar att smarttelefoner är betydligt mer sårbara for GPS-L1 forfalskningsattacker då de accepterade GPS-L1 signaler med betydande position, tid, och datafel medans motsvarande Galileo E1-B/C signaler ej accepterades. Trots resultaten så är det viktigt att inte dra för starka slutsatser då underlaget var kraftigt begränsat givet rådande omständigheter (Covid), som gjorde det svårt/omöjligt att på ett säkert sätt samla volontärer med olika smarttelefoner för våra experiment. Därav så är det viktigt att i framtiden utöka arbetet med ett större underlag och fler signaltyper.

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49

Drossart, Pierre. "Etude par spectroscopie infrarouge de l'atmosphère de Jupiter : de Voyager à Galileo." Paris 11, 1985. http://www.theses.fr/1985PA112158.

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Cette thèse réunit des travaux de spectroscopie infrarouge sur l’atmosphère de Jupiter. Les spectres de l’instrument IRIS de Voyager 1 ont été analysés à 5 microns à l’aide d’un calcul numérique de spectres synthétiques. Les abondances moléculaires de PH₃, CH₃D, GeH₄ et H₂O ont été mesurées. Des variations d’abondance de plusieurs constituants ont été mesurées sur les spectres Voyager pour H₂O et à partir d’instruments au sol pour PH₃ et C₂H₂. L’interprétation de ces variations pourrait être différente pour chacune des molécules: H₂O condensable varierait en fonction des mouvements convectifs verticaux. PH₃ en raison de variations des conditions convectives et chimiques équilibrant sa production et sa destruction et C₂H₂ en raison des variations de l’éclairement UV ou des précipitations de particules chargées dans l’atmosphère. Ce travail consiste aussi en une préparation des observations par l’instrument NIMS de la sonde Galileo (en orbite autour de Jupiter en 1989) et un calcul prévisionnel des spectres observables par NIMS est effectué à 5 à 3 microns. En conclusion sont présentées les théories de la dynamique de Jupiter en concurrence à l’heure actuelle et un projet de calcul numérique de la convention sphérique qui pourrait être adapté à Jupiter
This work is devoted to the study of the atmosphere of Jupiter by infrared spectroscopy. Spectra of the instrument IRIS on Voyager 1 are analyzed at 5 microns by comparison to synthetic spectra. The molecular abundances of PH₃, CH₃D, GeH₄and H₂O are derived. Variations in the abundances of several constituents are measured from the Voyager spectra for H₂O and from ground-based instruments for PH₃ and C₂H₂. The interpretation of these variations could be different for each molecule H₂O , which is condensable, could vary with the convective vertical motions of the atmosphere, PH₃ by chemical and convective variations, which equilibrate its production and its destruction and C₂H₂ by the variations of the UV insolation or by the precipitation of charged particules in the stratosphere. This work is also a preparation to the observations by the NIMS instrument of Galileo (in orbit around Jupiter in 1989), by a calculation of the spectra observable at 5 and 3 microns. In conclusion, several theories of the dynamics of Jupiter are presented, with a project of numerical simulation of the spherical convection, which could be adapted to Jupiter

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50

Arora, Balwinder Singh. "Evaluation of ambiguity success rates based on multi-frequency GPS and Galileo." Thesis, Curtin University, 2012. http://hdl.handle.net/20.500.11937/500.

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The precise positioning applications have long been carried out using dual frequency carrier phase and code observables from the Global Positioning System (GPS). The carrier phase observables are very precise in comparison to the code ones, the reason phase observables play an important role in precise geodetic applications. The carrier phase observables can have precision of about 3 millimeters. However the precision of the estimated parameter of interest, say the receiver position, depends upon the correct resolution of integer ambiguities present in the carrier phase observables. Significant contributions have been made in the last couple of decades towards integer ambiguity estimation to make precise positioning applications possible, using GPS carrier phase and code data from geodetic receivers.Precise positioning applications have been successful in the past, but at the cost of time taken to correctly resolve the integer ambiguities. This delay in integer ambiguity estimation is caused due to the presence of various propagation and hardware related effects present in the observables of GPS or in that case, any other Global Navigation System. The propagation errors related to the atmosphere are significant for medium to long baseline lengths. Among the atmospheric errors, the ionosphere is found to have profound effect on the process of integer ambiguity estimation. With the aid of permanent reference networks, corrections for ionosphere could be interpolated and further transferred to the user with an aim to enhance users ambiguity resolution and fulfill the aim of an efficient and reliable precise positioning.With the advancement of Global Navigation Satellite Systems (GNSS) several of the limiting factors which degrade users ambiguity resolution are seen to be met. The relatively poor precision of the code data in comparison to the phase data, is foreseen to improve for third GPS frequency, also called as GPS L5. Also most of the frequencies on Galileo system would have improved code precision.The ionosphere which has been a major blockade in fast integer ambiguity resolution, for long baseline lengths, would also benefit in a multi-frequency, multi-GNSS scenario. Since a GNSS model, in which the ionosphere is considered unknown and estimated, gains strength with addition of a frequency. The addition of L5 on GPS and availability of up to four frequencies on Galileo system would strengthen the GNSS model which would be beneficial when ionosphere is parameterized for estimation. This study aims at understanding the above mentioned and other possible benefits of the future GPS and Galileo system.The benefits that the future GPS and Galileo can bring to precise applications can be evaluated in terms of correct resolution of integer ambiguities present in the carrier phase data and further by understanding the contribution of the ambiguity resolution towards improvement of fixed-precision of the parameters of interest. The correct resolution of ambiguities was judged by computing the probability of correct integer bootstrap along with LAMBDA decorrelation method. The decorrelation of the ambiguity Variance Covariance matrix resulted the probability of Integer Bootstrap to correspond to lower bounds for the probability of Integer Least Square. The ambiguities were considered to be successfully resolved only after a minimum of 0.999 probability could be obtained from Integer Bootstrap. While all the ambiguities collectively contributed to give 0.999 Ambiguity Success Rate (ASR) it was termed as full Ambiguity Resolution (AR). In scenarios when full AR took large number of epochs to give 0.999 ASR, only a subset of ambiguities were fixed which met the 0.999 ASR criteria. This approach is known as Partial AR (PAR). PAR solution was accepted only when the resolved subset of ambiguities could contribute to give a minimum value of fixed-precision for the parameters of interest. Since this research involves future GPS and Galileo system, GNSS observables, real or simulated were not used. Instead simulations were done based on model assumptions, that is the functional and the stochastic model.This research work focuses on understanding the benefits of multi-frequency GPS and Galileo to its core. This was done by planning multiple scenarios of GNSS frequencies, GNSS combinations, atmospheric considerations, latitudinal variations and baseline orientations. With the aid of this multiple scenario simulation, an estimate for time taken for successful AR and the fixed-precision of parameters of interest obtained after successful AR could be computed for a range of possible situations. When a multi-GNSS scenario consisting of future GPS and Galileo was considered, there have been challenges while a mathematical model for multi-GNSS was being formed. The design of the multi-GNSS mathematical model accounted for the Inter System Biases (ISB’s) which surface while different GNSS systems use the same reference satellite. While a rank defect between the ISB’s and the ionosphere was detected, it was mitigated by choosing an appropriate S-Basis. To make the simulation software robust and realistic, accounting for setting and rising satellites and change of reference satellite was implemented. With the above considerations a multi-GNSS, multi-frequency simulation software was developed in MATLAB programming language. The results have been obtained based on assumption in the functional and stochastic models. In real practice unmodelled errors have an impact on ASR and time to fix the integer ambiguities to its correct solution due to multipath , insufficient knowledge of the stochastic model, etcetera.Presented below are some of the important findings of this study.The Geometry Free model does not gain strength with the addition of satellites. Since with addition of a satellite a receiver-satellite range is added to the unknowns. Also for a combined GPS and Galileo system, the Geometry Free model does not have a coupling parameter in the unknowns, say troposphere or receiver coordinates. Hence while the mathematical model is formed, from a single system to a combined system, the model does not gain strength. Hence a multi-GNSS constellation would not help to reduce the time-to-fix integer ambiguities for a Geometry Free model.The permanent reference networks can benefit from an integrated GPS and Galileo system. The precision of the ionospheric estimates with a permanent network could reach 2cm instantaneously, almost any time of the day by using quadruple frequency (L1pE1q, L5pE5aq, L2,E5b) GPS and Galileo combined system with the aid of PAR.While the user aims at performing relative positioning using a permanent network, the benefits from a combined GPS and Galileo system are immense. For a user with low-end single frequency receiver, for short baseline lengths ( 10Km), obtaining its receiver positions with 2cm precision for north- and east-components and 6cm precision for the up-component would be possible instantaneously using a combined GPS and Galileo. While the user is equipped with ionospheric corrections from the network, all the ambiguities could be resolved in a short time with a combined GPS and Galileo quadruple frequency system (L1pE1q, L5pE5aq, L2,E5b). The findings from this simulation study shows that, while ionosphere corrections are given to the user, all the ambiguities could be successfully resolved (full AR) within 20 epochs (1 second sampling) by using quadruple frequency from an integrated GPS and Galileo system.

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Dissertations / Theses on the topic 'Galileo'

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