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

O ressurgimento do sujeito pela escrita autobiográfica: o caso de Nikola Tesla (1856-1943) / The resurgence of the subject by autobiographical writing: the case of Nikola Tesla (1856-1943)

Lima, Aline Alves 17 March 2017 (has links)
Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-04-11T20:15:10Z No. of bitstreams: 2 Dissertação - Aline Alves Lima - 2017.pdf: 1715140 bytes, checksum: 001fef1bb24d58a2ed8a84ea441e8d3b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-04-12T14:32:24Z (GMT) No. of bitstreams: 2 Dissertação - Aline Alves Lima - 2017.pdf: 1715140 bytes, checksum: 001fef1bb24d58a2ed8a84ea441e8d3b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-12T14:32:25Z (GMT). No. of bitstreams: 2 Dissertação - Aline Alves Lima - 2017.pdf: 1715140 bytes, checksum: 001fef1bb24d58a2ed8a84ea441e8d3b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This dissertation investigates the status of autobiographical writing for Nikola Tesla (1856- 1943). Not the dawn of the twentieth century, this Serbian-American inventor threw himself into the autobiographical enterprise. In it is present Tesla's eagerness for recognition as a "great inventor" who he believed to be. Its trajectory was characterized by the passage of the glorious moment that it experienced in the scientific community to the process of ostracism in which it was. His decline was not only financial or professional, but especially existential, since his time was what made sense to his life. Convinced of the excellence of his work, Nikola Tesla built an autobiography project, conceived as a concept of perception of the importance of his inventions to the world. For him, only the ideal inventors, who participate that the class of "exceptionally privileged class" would guard the world from eminent destruction. The autobiography was used as a model for Tesla to transform a conception of people, altering the existing world and turning it into an ideal place where its actualization is not more serious through writing, but through its inventions, its main purpose would consist of Safeguard a humanity from the catastrophe. The autobiographical writing was perceived by Nikola Tesla as a resource to transform the existing world, and to resurface as an ideal inventor. / Essa dissertação investiga o estatuto da escrita autobiográfica para Nikola Tesla (1856-1943). No alvorecer do século XX, esse inventor sérvio-estadunidense se lançou ao empreendimento autobiográfico. Nele é presente a ânsia de Tesla por um reconhecimento enquanto o “grande inventor” que acreditava ser. Sua trajetória foi caracterizada pela passagem do momento glorioso que experimentou na comunidade científica ao processo de ostracismo no qual se encontrava, no momento da escrita. Seu declínio não foi apenas financeiro ou profissional, mas sobretudo existencial, já que seu ofício era o que fornecia sentido para sua vida. Convicto da excelência de seu trabalho, Nikola Tesla construiu um projeto autobiográfico destinado a alterar as concepções correntes responsáveis por impossibilitar a percepção da importância de suas invenções para o mundo. Para ele, só os inventores ideais, que participavam do que denomina de “ classe excepcionalmente privilegiada” resguardaria o mundo da destruição eminente. A autobiografia foi utilizada como meio para Tesla transformar a concepção das pessoas, alterando o mundo existente e o transformando em um lugar ideal aonde sua atuação não mais seria por meio da escrita, mas sim através de suas invenções, cuja principal finalidade consistiria em resguardar a humanidade da catástrofe. A escrita autobiográfica foi percebida por Nikola Tesla como recurso para ele transformar o mundo existente, e ressurgir enquanto um inventor ideal
22

Bezdrátový přenos výkonu / Wireless transfer of energy

Varga, David January 2011 (has links)
ork tie together on first project, in which the was designed apparatus for tests wireless transmission energy. Antenna was synthesized and theoretically optimized for experimental operation, in which the will performed series measuring. In first part is practical description of realization proposal. It consists of circuital solution, proposal measuring workplace and mechanical construction with illustration photographs of arrangement. Second part includes results of performed measuring. These measuring will divided by three basic groups: in first group will by testing feature one’s antennae, in second group will series transmission measuring power gain, and in third group will photographed shape of field, and comparison with simple simulation finite difference method. Third part summarises results from measuring, and prepares consecutive balancing visualisation project, which is of thematic bent on chosen aspects theoretical hypothesis and effected experiments.
23

Nikola Tesla e os estudos do Raio X: releitura de uma história quase apagada

Souza, Aroldo Quinto de 26 October 2016 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-12-02T13:27:56Z No. of bitstreams: 1 Aroldo Quinto de Souza.pdf: 3320273 bytes, checksum: f5070aee946a5c26406bb0fde711b0d2 (MD5) / Made available in DSpace on 2016-12-02T13:27:56Z (GMT). No. of bitstreams: 1 Aroldo Quinto de Souza.pdf: 3320273 bytes, checksum: f5070aee946a5c26406bb0fde711b0d2 (MD5) Previous issue date: 2016-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The period from the late nineteenth century and early twentieth century, It was marked, among other things, by enable the widespread use of electricity and the discovery of the use of radiation. The Croatian inventor naturalized American Nikola Tesla developed a prominent role in both areas. With this research, we intend to contribute to the studies about Nikola Tesla and his work, the intention that his name again to be among the great scientists of his time, unlinked it from the esoteric sphere, with which it is so often associated and understanding why this association.. This thesis was developed in intention to accompany the discovery and development in applications of X-rays, emphasizing the contributions that Tesla developed for this area of science. His contributions to the discovery of the radiation will be analyzed, as well as the equipment developed by him for this purpose. From this research, it was possible to analyze how has the discovery, communication and reception by the scientific community and the ordinary people of the Information that X-rays could be used to photograph the inside of the human body, and risks associated with their use inconsequential / O período compreendido entre o final do século XIX e início do século XX, foi marcado, entre outras coisas, por possibilitar o uso em larga escala da eletricidade e pela descoberta do uso das radiações. O inventor croata naturalizado americano Nikola Tesla, desenvolveu um papel de destaque em ambas as áreas. Com esta pesquisa, pretendemos contribuir para os estudos sobre Nikola Tesla e sua obra, na intenção de que seu nome volte a figurar entre os grandes cientistas do seu tempo, desvinculando-o da esfera esotérica, com a qual, é tão comumente associado, entendendo o porquê desta associação. Esta tese foi desenvolvida no intuito de acompanhar a descoberta e evolução nas aplicações dos raios X, dando ênfase às contribuições que Tesla desenvolveu para esta área da ciência. Serão analisadas suas contribuições para a descoberta das radiações, bem como os equipamentos desenvolvidos por ele para este fim. A partir desta pesquisa, foi possível analisar como se deu a descoberta, a comunicação e a recepção pela comunidade científica e pelas pessoas comuns da informação de que, os raios X poderiam ser utilizados para fotografar o interior do corpo humano, além dos riscos associados à sua utilização inconsequente
24

Conception d'un système de cogénération solaire applique à l'habitat, associant un concentrateur miniature et une turbine de telsa / Design of a solar cogeneration system applied to the habitat, involving a miniature concentrator and a Tesla turbine

Jourdan, Arnaud 08 November 2013 (has links)
La responsabilité de notre activité dans les récentes et parfois brutales modifications climatiques est avérée. Maîtrise de la demande en énergie et énergies renouvelables apparaissent comme les deux solutions pour remédier à cette catastrophe. Dans ce travail, nous nous intéressons à la cogénération appliquée aux bâtiments résidentiels. Deux zones géographiques sont concernées, l'Afrique de l'Ouest et la France. Il n'existe pas de système de cogénération solaire de très faible puissance (< 10 kWe). La solution envisagée dans ce travail consiste à produire de la chaleur à environ 150 °C et un rendement supérieur à 50 %, de l'utiliser ensuite dans un ORC pour produire électricité et chaleur à basse température. Le système complet doit être résistant et à bas coût. Or pour atteindre ces performances, la concentration solaire est obligatoire. Une partie de ce travail consiste donc au développement d'un panneau à concentration solaire qui répond à ces deux contraintes thermiques, mais aussi au fait d'être robuste, fiable et facilement intégrable à l'enveloppe d'un bâtiment. Dans ce cadre, la technologie cylindro-parabolique a été retenue, adaptée et miniaturisée. En ce qui concerne la partie thermodynamique, le verrou technologique se trouve principalement dans le groupe turboalternateur. L'objet de la seconde partie de cette thèse consiste ainsi à la conception d'un organe de détente également robuste, nécessitant qu'une maintenance simplifiée et réalisable par les équipes de SIREA. La turbine Tesla, brevetée en 1913 par Nikola Tesla, devrait satisfaire à ce cahier des charges. Sa particularité est qu'à l'opposée des autres turbines, son rotor ne possède pas d'aubage, mais seulement des disques parallèles. Son fonctionnement est basé sur l'adhésion du fluide aux surfaces des disques. / The responsibility of our activity in the recent and sometimes brutal climate changes is recognized. Energy demand management and renewable energies appear as two solutions to overcome this disaster. In this work, we focus on combined heat and power applied to residential buildings. Two geographical areas are concerned, West Africa and France. For the moment, no system of very low power (< 10 kWe) solar cogeneration exists. In this work, considered solution consists to produce heat at 150 °C and with an efficiency greater than 50 %, then to use it in an ORC for producing electricity and low temperature heat. The whole system has to be resistant and low-cost. But to reach those performances with solar radiation, concentration is necessary. The first part of this thesis is to elaborate a solar concentrating panel which answer to these two thermal constraints. The new solar panel must be robust, reliable and easily integrable on the building envelope. In this context, parabolic trough is adopted, adapted and miniaturised. Regarding the thermodynamic part, technological lock is found mainly in the turbogenerator. The purpose of the second part of this thesis consists of the design of a an expansion equipement, requiring simplified maintenance and achievable by the team of Sirea. The Tesla turbine, patented in 1913 by Nikola Tesla, should satisfy this specification. Its characteristic is that the opposite other conventional turbines, the rotor is not bladed or vaned, only parallel disks. Fluid exerts shear stress on the disk surfaces resulting in a torque at the shaft.
25

Secure and Privacy-Preserving Decentralized Wi-Fi Aware Service Discovery Architecture / En Wi-Fi Aware -Decentraliserad säker serviceupptäcktsarkitektur i mobilt ad-hoc-nätverk

Wang, Jiahao January 2022 (has links)
In modern Mobile Ad hoc Networks (MANETs), service discovery is a major component for mobile devices to exchange data and find available services. However, service discovery architectures developed and adopted by the industry either are not appropriate for MANETs or cannot provide security and privacy protection to clients. Service discovery architectures could be either directory-based or directory-less. Both of the two types of architectures suffer from certain security or privacy issues: The directory-based architecture requires a directory server to facilitate communication between service providers and users, which makes the directory server a single point of failure and may harm users’ privacy if the directory server is honestbut- curious; the directory-less architecture solves these two problems but without a trusted directory, the Denial of Service (DoS) attacks can be easily performed on all entities in the system since the mutual authentication between entities consumes significant computational resource. Wi-Fi Aware, a recently introduced Wi-Fi-based connectivity, allows MANETs nodes to discover and connect directly to each other without any infrastructure. Moreover, the size of the message transmitted in this process is large enough (around 255 bytes) for security and privacy protection. So in this thesis, we implemented a Wi-Fi Aware-based decentralized secure service discovery system that allows the clients to directly discover nearby service providers and provide mutual authentication between them without a directory server. In our system we leverage several schemes, including bloom filter, Timed Efficient Stream Loss- Tolerant Authentication (TESLA), and client puzzle. A set of experiments are carried out for the evaluation of the implemented system. The evaluation results show that our system meets most of the security requirements of service discovery architectures with acceptable processing delays. / I moderna moblie ad hoc -nätverk (MANETs) är service discovery en huvudkomponent för noder för att utbyta data och hitta andras tjänster. Men serviceupptäcktsarkitekturerna som utvecklats och antagits av branschen är antingen inte lämpliga i MANET eller kan inte ge kunderna säkerhet och integritetsskydd. service discovery-arkitekturer är katalogbaserade eller kataloglösa. Båda de två arkitekturerna lider av vissa säkerhetseller sekretessproblem: Den katalogbaserade arkitekturen kräver att katalogservern underlättar kommunikationen mellan tjänsteleverantörer och användare, vilket gör katalogservern till en enda felpunkt och kan skada användarnas integritet om katalogservern är ärlig-men-nyfiken; Den kataloglösa arkitekturen löser dessa två problem men utan en pålitlig katalog kan Denial of Service (DoS) -attacker enkelt utföras på alla enheter i systemet eftersom den ömsesidiga autentiseringen mellan enheter förbrukar massor av beräkningsresurser. Nyligen, med den nyaWi-Fi-funktionen som kallas WiFi-Aware cite wifiaware, kan MANET-noder upptäcka och ansluta direkt till varandra utan någon annan typ av anslutning mellan dem . Dessutom är storleken på meddelandet som överförs i denna process tillräckligt stor (cirka 255 byte) för säkerhetsautentisering. Så i denna avhandling implementerade vi ett Wi-Fi Aware-baserat Decentralized Secure service discovery-system som gör att klienterna direkt kan upptäcka närliggande tjänsteleverantörer och tillhandahålla ömsesidig autentisering mellan dem utan en katalogserver. I vårt system används flera system för att skydda vårt system från ovanstående säkerhets- och integritetsfrågor, bland annat blomfilter, Timed Efficient Stream Loss-Tolerant Authentication (TESLA) och klientpussel. En uppsättning utvärderingsförsök utförs för det implementerade systemet. Utvärderingsresultaten visar att vårt system uppfyller de flesta säkerhetskraven för service discovery -arkitekturer med en acceptabel bearbetningsfördröjning.
26

Development of proton magnetic resonance spectroscopy in human heart at 3 Tesla

Rial Franco, B. January 2010 (has links)
Cardiovascular magnetic resonance imaging (MRI) is a well established technique in clinical cardiology. Different MRI sequences are routinely used to assess cardiac anatomy, function, viability and other parameters that aid diagnosing cardiac disease. Conversely, cardiac magnetic resonance spectroscopy (MRS), the only available method for a non-invasive study of human cardiac metabolism, has not evolved into a clinical tool yet. The combination of both techniques holds great potential to gain insight into the causality of cardiomyopathy diseases or other medical conditions with high cardiovascular risk profile, like diabetes or obesity and improve the clinical management of cardiac diseases. Nowadays, high field clinical MR systems have the great potential of improving the low spatial and temporal resolution and reproducibility of MRS. The aim of this thesis was to develop and implement a cardiac 1H-MRS method at 3 T that can be applied in clinical routine for the assessment of creatine and lipid levels in the human myocardium. The methodological developments to advance cardiac MRS are presented first. A robust 1H-MRS method comprising an optimized single-voxel technique, phased-array coil combination routine, optimized water suppression, breath-hold averaging and post-processing methods were developed. First, reproducibility and feasibility of the method were validated in vivo by acquiring 1H-MRS of the liver in almost one hundred healthy subjects. Subsequently, myocardial lipids levels were obtained in healthy volunteers by single breath-hold 1H-MRS triggered to mid-diastole, showing good reproducibility in an acquisition time less than 12 s. The good spectral resolution achieved using this method was demonstrated by the ability to differentiate for the first time two pools of myocardial lipids in spectra from the septum of patients with suspected myocardial lipid excess. Finally, creatine levels for healthy volunteers were investigated using multiple breath-hold acquisitions. Thus, this study shows the practicality and feasibility to incorporate this rapid cardiac 1H-MRS method into clinical studies of the human myocardium.
27

Artificiell intelligens (AI), självkörande fordon och lagöverträdelser : Kan någon hållas straffrättsligt ansvarig?

Larsson, Daniel January 2016 (has links)
Eftersom det under de senaste åren skett en explosionsartad utveckling av deep learning och AI är det av intresse att utreda hur det svenska straffrättssystemet klarar av denna teknikutveckling. Frågan uppstår om vem som ska hållas straffrättsligt ansvarig när AI begår lagöverträdelser. Det finns, så vitt jag har funnit, ytterst lite skrivet om just denna problematik. Jag strävar emellertid inte efter att besvara hur problemen med AI ska lösas överlag eftersom detta skulle blir alldeles för omfattande för denna uppsats. Istället kommer frågan om vem som kan hållas straffrättsligt ansvarig när AI begår lagöverträdelser att utredas genom två fiktiva exempel om vållande till annans död. I var sitt exemplen har två självkörande fordon, ett som kräver mänsklig övervakning samt ett som saknar både ratt och pedaler, krockat med en annan trafikant.  De potentiella gärningsmännen i exemplen är det självkörande fordons AI som inte bromsar, den fysiska personen i fordonet som aktiverar autopiloten och sedan inte själv bromsar, och någon person i det företag som tillverkar eller säljer det självkörande fordonet. Varje gärningsman måste begå en egen otillåten gärning eftersom det annars skulle bli vikarierande ansvar, dvs. att någon döms för någon annans gärning. Uppsatsen behandlar bl.a. underlåtenhet och företagaransvar.
28

Spark Gap

Cox-Richard, Lillian 01 January 2008 (has links)
"Spark Gap" is an invisible electrical force made visible in spaces between things. This usually describes the space of air between two conductors; a non-conductive gap in an otherwise complete electric circuit, across which a quick luminous disruptive electrical discharge occurs. This interstitial space is the distance between two ideas, arced with a running leap. The arc can also be the difference between two things, a gap that becomes apparent only when the two are held in close proximity. In my thesis exhibition, "Spark Gap," a sea urchin shaped orb sits atop a tower of ladders. The orb is broken into five sections and reassembled, each fault line occurring along the perfect zigzag line of its cellular structure. On the floor, there is a linen shag rug, marked as if struck by lightning. This exhibition is named for an interstitial charge, arcing across distance or difference. But this charge is also found in intersections and similarities. Imagine the friction created by rubbing together the circles of a Venn diagram: the overlapping section would begin to spark. It is in these gaps and overlaps that I find the impetus for my work.
29

Production of Sleptons in e¯e¯-Collisions / Produktion von Sleptonen in e¯e¯-Kollisionen

Wagner, Alexander January 2008 (has links) (PDF)
Supersymmetry is currently the best motivated extension of the Standard Model and will be subject to extensive studies in the upcoming generation of colliders. The e-e- mode would be a straight forward extension to the currently planed International Linear Collider, planned to operate in e+e- mode. The low background in this mode may prove advantageous in the study of CP- and Lepton Flavour Violtation. In this work a CP sensitive observable based on transverse beam polarisation is introduced and the impact of neutralino mixing on the total cross section in cas of non-vanishing CP-violtating phases is studied in representative scenarios including non-GUT scenarios. Additionally, the mixing of sleptons is studied in the context of LFV, an analytical approximation is developed, and possible background free measurements of these effects are investigated. / Supersymmetrie ist derzeit die bestmotivierte Erweiterung des Standardmodells und wird in der nächsten Generation von Beschleunigern intensiv studiert werden. Der e-e- Modus des geplanten International Linear Collider, welcher zunächst im e+e- Modus betrieben werden soll, stellt hier eine direkte Erweiterung da, die durch ihren niedrigen Untergrund vorteilhaft für das Studium CP- und Lepton Flavour verletzender Effekte sein kann. In dieser Arbeit wird eine CP sensitive Observable basierend auf transversaler Strahlpolarisation vorgestellt sowie der Einfluss der Neutralinomischung auf den totalen wirkungsquerschnitt im Falle nichtverschwindender CP-verletztender Phasen in repräsentativen Szenarien, auch non-GUT-Szenarien, untersucht. Ferner wird die Mischung der Sleptonen im Kontext von Lepton-Flavour-Verletzung näher beleuchtet, eine analytische Näherung entwickelt und die möglicherweise Untergrundfreie Messung dieser Effekte untersucht.
30

Mesure de glutamate cérébral chez l'homme et le petit animal par spectroscopie RMN in vivo, application à la maladie de Parkinson

Kickler, Nils 30 June 2006 (has links) (PDF)
Ce travail a eu comme objectif de mettre en place des techniques de spectroscopie RMN du proton optimisées pour la détection du glutamate cérébral afin d'étudier des changements éventuels du métabolisme glutamatergique dans la maladie de Parkinson. En vue d'une application chez le patient, une approche de filtrage à double quanta et une méthode liée à la spectroscopie bi-dimensionnelle ont été évaluées à 3 Tesla sur un imageur corps entier. Une étude incluant dix patients atteints par la maladie de Parkinson idiopathique et dix volontaires sains a ensuite été réalisée, utilisant une méthode liée à la spectroscopie bi-dimensionelle et ciblant le noyau lenticulaire (putamen et globus pallidum). Aucun changement significatif du glutamate total (intra- et extracellulaire) n'a pu être mis en évidence comparant le patient sous traitement par levodopa (L-DOPA) ou ayant temporairement interrompu son traitement et le volontaire sain. Une tendance à la diminution de la creatine/phosphocreatine a été observée chez le patient. En vue d'une étude complémentaire sur le modèle animal, la méthode mise en œuvre chez le patient a été évaluée chez le rat à 7 Tesla. Une étude sur le rat traité par 6-hydroxydopamine (6-OHDA) a ensuite été réalisée, utilisant une séquence PRESS standard à un temps d'écho de 136 ms et ciblant le striatum. Sur le même animal, des spectres avant traitement à la 6-OHDA, après traitement et suivant une injection de levodopa ont été acquis. Aucun changement de glutamate n'a pu être mis en évidence, alors qu'une tendance à la réduction de la choline suivant le traitement à la 6-OHDA était observée. Nos résultats indiquent que les changements du métabolisme glutamatergique, ayant lieu dans le cadre de la maladie de Parkinson qui ont été mis en évidence dans le modèle 6-OHDA par d'autres méthodes, ne sont pas reflétés par des changements des concentrations du glutamate total mesuré par RMN in vivo.

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