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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.
1

Clips moléculaires à base de tétrathiafulvalène : Synthèse et reconnaissance de molécules neutres électrodéficientes / Molecular clips based on tetrathiafulvalene : Synthesis and recognition of electro-deficient neutral molecules

Cotelle, Yoann 09 October 2014 (has links)
Le tétrathiafulvalène (TTF) est l'une des molécules hétérocycliques les plus étudiées de ces quarante dernières années en raison de ses propriétés électroniques remarquables. En tant que donneur d’électrons, il a ainsi été associé à des molécules acceptrices d’électrons pour former des complexes de transfert de charge. Néanmoins, son intégration dans des architectures de type clips moléculaires reste pour l’instant limitée. Ce travail est dédié à la synthèse et aux caractérisations spectroscopiques et électrochimiques de clips moléculaires associant deux bras TTF articulés autour d’une plateforme rigidifiée de type glycolurile ou conformationnellement plus flexible avec le motif quinoxaline. Nous avons ainsi synthétisé des édifices moléculaires en forme de pince qui présentent une taille de cavité et un pouvoir donneur modulables. L’étude porte ensuite sur les propriétés de reconnaissance de molécules invitées neutres électrodéficientes planes (m-dinitrobenzène, TCNQ-F4, macrocycles de type bis-bipyridinium) ou tridimensionnelles (fullerène C60). Ces phénomènes de reconnaissance sont favorisés par l’établissement d’interactions de type donneur-accepteur. Nous présentons également la synthèse d’une architecture originale en forme de double pince avec l’objectif de pouvoir réaliser une double reconnaissance spécifique d’accepteurs d’électrons. Un autre domaine de la chimie supramoléculaire est abordé avec la mise en évidence en solution d’un phénomène d’agrégation de ces clips moléculaires, qui peut permettre d’envisager l’accès à des matériaux hautement auto-organisés à l’état solide. / No english summary
2

Polycyclic Aromatic Hydrocarbons with Corannulene Subunits

Yanney, Michael 11 May 2013 (has links)
The study of polycyclic aromatic hydrocarbons (PAHs) with curved surfaces, also known as buckybowls or fullerene fragments, represent an area which is under intense investigation by organic chemists and material scientists. This dissertation describes research that contributes to this field. The availability of multi-gram quantities of the smallest buckybowl, corannulene, has led to the synthesis of several larger systems with buckybowl subunits. Cyclotrimerization of corannulyne using palladium(0) as the catalyst is described. The resulting product, C60H24, is a highly nonplanar hydrocarbon with very interesting conformational dynamics. The X-ray crystallography of the cyclotrimer confirms the “twist” conformation with C1 symmetry. The cyclotrimer also shows three distinct corannulene bowls with very different inversion barriers as confirmed by both experiment and calculations. The bowl to bowl inversion of the corannulene bowl with the lowest inversion barrier results in pseudorotation of the cyclotrimer, which gives rise to a symmetrized 1H NMR spectrum exhibiting 12 distinct proton signals. 1H NMR line shape analysis gives an estimation of the inversion barrier at 8.5 – 8.6 kcal/mol. The tetrameric hydrocarbon C80H32 was synthesized through the Diels-Alder reaction of the cyclotrimer and 1,2-didehydrocorannulene. The six membered rings adjacent to the central ring in the cyclotrimer are activated enough to react with another corannulyne. The tetramer exhibits different conformational and optical absorption properties when compared to the cyclotrimer. The tetramer (C80H32), which is highly nonplanar and sterically congested, represents the largest fully characterized oligomer of corannulyne reported to date. This is also the first reported example of a cycloaddition reaction in which a corannulene subunit acts as a diene. A tripodal molecular receptor (C87H54O6) with three corannulene pincers and a cyclotriveratrylene tether was synthesized. The molecular receptor was evaluated by 1H NMR titration in toluene-d8 for its ability to bind fullerenes. The experiment demonstrates the formation of 1:1 inclusion complexes of the molecular receptor with fullerenes and provides the association constants of 1500 plus or minus 50 and 1180 plus or minus 30 M-1 for C60 and C70, respectively.
3

Ανάπτυξη mobile εφαρμογής για τον προγραμματισμό ιατρικών εξετάσεων με υποστήριξη από ευφυές σύστημα

Δημόπουλος, Σπυρίδων Κωνσταντίνος 05 February 2015 (has links)
Το θέμα της διπλωματικής αφορά τη δημιουργία μίας mobile εφαρμογής για προγραμματισμό ραντεβού με γιατρούς και ταυτόχρονα πρόταση γιατρού από ένα ευφυές σύστημα με βάση τη συλλογή συμπτωμάτων. Ο ασθενής έχει τη δυνατότητα να αναζητήσει γιατρούς που είναι καταχωρημένοι στο σύστημα με χρήση της έξυπνης κινητής συσκευής του. Τα κριτήρια αναζήτησης είναι η πόλη, η ειδικότητα ο τύπος της ασφάλισης (ιδιωτική ή δημόσια). Τα αποτελέσματα εμφανίζονται σε μία λίστα ή σε χάρτη. Τα αποτελέσματα ταξινομούνται με βάση την απόσταση της θέσης του χρήστη από το κάθε ιατρείο. Στο χάρτη ο χρήστης επιβλέπει όλα τα ιατρεία καθώς και τη θέση του. Στη λίστα παράλληλα με τις πληροφορίες κάθε ιατρού εμφανίζεται η ημερομηνία και η ώρα του επόμενου ελεύθερου ραντεβού του. Ο ασθενής επιλέγει έναν ιατρό από τη λίστα και μεταβαίνει στο προφίλ του ιατρού. Εκεί μαζί με τις πλήρεις πληροφορίες του ιατρού εμφανίζεται ένα ημερολόγιο με τα διαθέσιμα ραντεβού του ιατρού. Ο ασθενής επιλέγει το ραντεβού που τον ενδιαφέρει και μεταβαίνει στην φόρμα προγραμματισμού ραντεβού. Εκεί συμπληρώνει τα στοιχεία του και το λόγο της επίσκεψης και ολοκληρώνει το ραντεβού. Αν ο ασθενής δεν έχει αποφασίσει για την ειδκότητα που χρειάζεται μπορεί να επιλέξει τη συμβουλή του ευφυούς συστήματος. Μετά από μία σειρά διαδοχικών ερωτήσεων, γενικών στην αρχή και ειδικότερων στη συνέχεια, το ευφυές σύστημα κατευθύνει τον ασθενή προς τη σωστή ειδικότητα ή στο σύνολο ειδικοτήτων. Οι ερωτήσεις δεν είναι ίδιες για κάθε ασθενή αλλά οι πιο ειδικές πυροδοτούνται από ένα σύνολο κανόνων που βασίζονται στις απαντήσεις του ασθενή στις γενικότερες ερωτήσεις. Τα δεδομένα εισόδου του ευφυούς συστήματος είναι στη μορφή απαντήσεων σε ερωτήσεις κειμένου, επιλογή γραφικών ή προέρχονται τη χρήση των αισθητήρων της έξυπνης κινητής συσκευής. Η υλοποίηση περιλαμβάνει τη χρήση CLIPS για το ευφυές σύστημα, τη χρήση HTML5 και JavaScript για την mobile εφαρμογή και PHP/SQL για τη διαχείριση της βάσης των διαγνωστικών ερωτήσεων και των ιατρών. / The issue of the thesis concerns the creation of a mobile application for scheduling appointments with doctors and physicians as well as providing a proposal of an intelligent system based on the collection of symptoms. The patient has the opportunity to seek doctors who are registered in the system using smart mobile device. The search criteria are the city, specificity type of insurance (private or public). The results are displayed in a list or on a map. The results are sorted by the distance of the position of the user from each doctor's position. On the map the user oversees all surgeries and his position. In the list along with the information of each doctor, the date and time of the next free appointment is displayed. The patient chooses a physician from the list and proceeds to the profile the doctor. There, together with the complete information of the physician, the user gets a calendar of available appointments of the physician. The patient chooses the date of the appointment and moves to the appointment form. There the user fills in the data and the reason of the visit and submits the appointment. If the patient is not certain of the specificity of the doctor the user needs, the user can choose the advice of the intelligent system. After a series of consecutive queries, the general principle and specific then the intelligent system directs the patient to the correct specificity. The questions are not the same for every patient, but they are triggered by a specific set of rules based on the responses of the patient. The input to the intelligent system is in the form of answers to questions of text, graphics or input from sensors. The implementation involves the use of CLIPS for intelligent system, using HTML5 and JavaScript for mobile application and PHP / SQL to manage the database of diagnostic questions and doctors.
4

VITALmaths - Transforming learning experiences through mathematical video clips

Samson, Duncan, Linneweber-Lammerskitten, Helmut, Schäfer, Marc 20 March 2012 (has links) (PDF)
No description available.
5

VITALmaths - Transforming learning experiences through mathematical video clips

Samson, Duncan, Linneweber-Lammerskitten, Helmut, Schäfer, Marc 20 March 2012 (has links)
No description available.
6

Produktutveckling av bärskena för pendlade armaturer / Product development of support rail for pendant luminaries

Linde, Jens, Gille, Ludwig January 2019 (has links)
Purpose – The purpose of this thesis was to follow up and further develop an existing product at Fagerhult AB. The product is a support rail for pendant luminaires. The support rail facilitates the positioning of the luminaire when mounted in the ceiling. The problem with today’s support rail is that it doesn’t meet the requirements set by Fagerhult AB according to aesthetics and flexibility. The request is instead a support rail that takes less space, more aesthetically appealing and more flexible. Methodology – The thesis has followed a product development process, from pilot study until prototype. First thing was a time planning to establish milestones to see when different parts of the project were supposed to be done. Then a pilot study was made in terms of market research and a competitor analysis to get a more complete picture of the today’s market and also what the market wanted. From the pilot study a complete requirement specification was made together with the customer. By the requirement specification a concept generation started in terms of brainstorming and morphologic matrix. The concepts were screened through elimination matrices and together with Fagerhult AB. The final concept was chosen from four more worked through concepts. Those concepts have all been made in a CAD-environment, Solid Edge, and physical prototypes have partially been made to be evaluated in different areas. The prototypes were evaluated in aesthetics, installation friendliness and manufacturing cost. The final concept was developed into a working prototype. Results – Already from the beginning the final result was divided into three different areas, T-clips, rail and sliding block. The final prototype consisted of a T-clips which was made in two pieces, spring steel and sheet metal. This was to offer an installation friendly support rail and also to make an opportunity to hide the T-clips which was previously exposed. The rail was designed with integrated covers on the ends and the opportunity to fit the sliding block inside, this was made to make the support rail more aesthetic appealing and to make sure that focus was not taken from the luminaire. The sliding block was then developed to fit inside the rail and suspension was offered for the wire loop. That way the wire loop, which is attached to the sliding block, could be hidden inside the rail. This resulted in an even more hidden supporting rail. To maintain the target value for the supporting rail the material was kept in standard and to some extent the construction had elements of already existing functions. Restrictions – Because of the lack of time the thesis only dealt with the product development process until prototype. The prototype was partially made by the writers themselves because Fagerhult AB:s prototype workshop had been busy. Neither FEM-calculations nor simulations was made to verify and optimize functions on the prototype, also this because of time constraints. / Syfte - Syftet med detta arbete var att vidareutveckla en befintlig produkt hos Fagerhult AB. Produkten är en bärskena för pendlade armaturer. Bärskenan underlättar positionering av armaturen väl monterad i undertaket som den är anpassad för. Problemet med dagens bärskena är att den inte uppfyller de krav som Fagerhult AB ställer gällande estetik och flexibilitet. En bärskena som tar mindre plats, mer estetisk tilltalande och mer flexibel efterfrågas.           Metodik - Utförandet av arbetet har följt en produktutvecklingsprocess, från förstudie till prototyp. Först gjordes en tidsplanering för att upprätta milstolpar när olika delar i projektet bör vara klara. Sedan gjordes en förstudie i form av marknadsundersökning och konkurrensanalys för att få en mer komplett bild av hur marknaden såg ut i dagsläget samt vad marknaden ville ha. Utifrån förstudien sammanställdes en definitiv kravspecifikation tillsammans med kund. Med kravspecifikationens grund påbörjades konceptgenereringen i form av brainstorming och morfologisk matris. Koncepten sållades sedan genom elimineringsmatriser och tillsammans med Fagerhult. Det slutgiltiga konceptet valdes utifrån fyra mer genomarbetade koncept. Dessa koncept är uppritade i en CAD-miljö, Solid Edge, och till viss del är fysiska prototyper framtagna för att utvärderas i olika områden. De utvärderades i estetik, installationsvänlighet och tillverkningskostnad. Det slutgiltiga konceptet utvecklades till en funktionsduglig prototyp. Resultat - Det slutgiltiga resultatet hade från början delats upp i tre olika delområden, T-clips, skena och glidblock. Den slutgiltiga prototypen bestod av ett T-clips som var tvådelat i fjäderstål och tunnplåt. Detta för att erbjuda en installationsvänlig bärskena samt möjligheten att dölja T-clipset som förr exponerats. Skenan utformades med integrerade täcklock på ändarna samt möjligheten att placera glidblocket inuti skenan, detta för att få en mer estetiskt tilltalande bärskena samt att fokus inte skulle tas från belysningsarmaturen. Glidblocket utvecklades för placering inuti skenan samt erbjöds upphängning av vajeröglan. På så sätt kunde vajeröglan, som fästs i glidblocket, döljas inuti skenan. Detta resulterade i att bärskenan doldes ytterligare. För att bärskenan skulle bibehålla målpriset behölls standardmaterial och till viss del hade konstruktionen inslag av redan befintliga funktioner. Begränsningar – På grund av tidsbristen behandlade arbetet endast produktutvecklingsprocessen fram till funktionsprototyp. En prototyp författarna själva till viss del fick ta fram därför att Fagerhult AB:s prototypverkstad varit belastad. Varken simuleringar eller FEM-beräkningar har utförts på prototypen för att verifiera funktionerna och optimera, även detta på grund av tidsbrist.
7

Single Function Agents and their Negotiation Behavior in Expert Systems

Dunskus, Bertram V. 05 November 1999 (has links)
"A Single Function Agent (SiFA) is a software agent, with only one function, one point of view, and one target object on which to act. For example, an agent might be a critic (function) of material (target) from the point of view of cost. This research investigates the possibilities and implications of the SiFA concept, and analyzes the definition language, negotiation language and negotiation strategies of the agents. After defining a domain-independent set of agent types we investigated negotiation, analyzing which pairs/groups of agents have reason to communicate, and what the information passed between them should be, as well as what knowledge was needed to support the negotiation. A library for the CLIPS expert system shell was built, which allows development of SiFA based expert systems from domain independent templates. We will present two such systems, one as implemented for the domain of ceramic component material selection and the other (in development) for simple sailboat design. The effect of negotiation on the design process and the results are discussed, as well as directions for future research into SiFAs."
8

Utilisation d’agrafes chirurgicales dans le suivi de tumeurs hépatiques appliquée à des traitements de radiochirurgie stéréotaxique par CyberKnife

Petitclerc, Léonie 08 1900 (has links)
Des avancements récents dans le domaine de la radiothérapie stéréotaxique permettent à un nombre grandissant de patients de recevoir un traitement non-invasif pour le cancer du foie. L’une des méthodes utilisées consiste à suivre le mouvement de la tumeur à l’aide de marqueurs radio-opaques insérés dans le foie grâce au système de suivi de l’appareil de traitement CyberKnife. Or, l’insertion de ces marqueurs est parfois trop invasive pour certains patients souffrant de maladie du foie avancée. Ces patients ont souvent un historique de chirurgie qui permet d’utiliser les agrafes chirurgicales déjà présentes dans leur foie dans le but de suivre leur tumeur. Cette nouvelle approche au traitement des tumeurs du foie est investiguée dans cette étude afin d’en déterminer les paramètres optimaux pour une meilleure pratique thérapeutique. L’expérimentation sur fantôme anthropomorpique a permis de conclure que le contraste des agrafes dans leur milieu augmente lors de l’augmentation des paramètres d’imagerie (kilovoltage et milliampérage de l’appareil de radiographie). D’autre part, l’erreur commise par le système CyberKnife dans l’identification des agrafes pour le suivi a été mesurée comme étant supérieure à celle sur l’emplacement des marqueurs radiologiques de platine (environ 1 mm contre moins de 1 mm). Cette erreur est considérée comme acceptable dans le contexte de ce type de traitement particulier. Enfin, une analyse gamma de l’impact dosimétrique du suivi par agrafes a montré qu’il était approximativement équivalent à celui par marqueurs de platine. De ces observations on conclue que le traitement des tumeurs du foie avec suivi des agrafes chirurgicales est valide et peut être amélioré suivant certaines recommandations cliniques. / Recent progress in stereotactic body radiation therapy allows an ever larger number of people to receive non-invasive treatment for liver cancer. One of the methods that were developed involves tracking the tumor’s movements, using radio-opaque markers which are inserted into the liver of the patient, with the help of the tracking system of the CyberKnife. However, the insertion of these markers is sometimes too invasive for patients with poor liver condition. These patients often have a history of surgery which allows the tracking of surgical clips that are already present in the liver as a surrogate for the tumor. This new approach to treating liver cancer is investigated in the present study in order to identify the optimal parameters for a better practice of this therapy. An anthropomorphic phantom experiment lead to the conclusion that the clip contrast in the tissue increases with an increase of the two imaging parameters (kV and mA of the x-ray tube). In addition, the error that was made on the identification of the position of clips by the CyberKnife system was measured as being slightly superior to the error on platinum marker positions (approximately 1 mm vs less than 1 mm). This error is considered acceptable in the context of this particular type of treatment. Finally, a gamma analysis of the dosimetric impact of clip tracking shows that it is approximately equivalent to that of platinum marker tracking. From these observations, we conclude that the treatment of liver tumors using surgical clips is valid and can be improved following this study’s clinical recommendations.
9

Liquefaction assessment and flume modelling of the Merriespruit gold and Bafokeng platinum tailings

Papageorgiou, George January 2003 (has links)
1 v., various pagings + 1 computer disk, 4 3/4 in. Thesis (Ph.D.) -- University of the Witwatersrand, 2004. / AC 2018
10

A MTV no Brasil: a padronização da cultura na mídia eletrônica mundial. / MTV in Brazil: the standardization of the culture on the world electronic media.

Lusvarghi, Luiza Cristina 24 June 2002 (has links)
Lançada em 1990, a MTV Brasil representa o primeiro empreendimento de um grande grupo internacional de mídia no País - a americana Viacom Inc, a terceira maior empresa do mundo – a operar com um conceito similar às franquias de fast food. Inicialmente licenciada para o Grupo Abril, a marca introduz o conceito de canal segmentado de televisão no Brasil, apesar de ser anterior às transmissões a cabo. Em 1996, a holding adota uma estratégia de expansão mundial mais agressiva. É criada a MTV Brasil Ltda, uma parceria da Abril com a Viacom. Em 1999, a Rede MTV adota a filosofia Thinks Globally, Acts Locally, mais adequada ao seu projeto de expansão global. Em contrapartida, a afiliada brasileira, em sua luta para adequar-se ao mercado local, reformula sua política de programação e passa a privilegiar em sua grade os não-musicais. O formato da MTV Networks e sua forma de expansão fazem da rede um emblema do processo de aculturação imposto pela globalização, equilibrando modos de produção dos países em desenvolvimento com a alta tecnologia do "Mundo Rápido". A questão que emerge é a forma como o mercado brasileiro incorpora essa nova tecnologia, a partir da trajetória da MTV Brasil, e entender até que ponto a entrada de marcas estrangeiras no segmento pode contribuir para o desenvolvimento da mídia nacional. / Launched in 1990, MTV Brazil represents the first enterprise in our country of a big international media company – the American Viacom Inc, the third largest in the world – which operates similar to the fast food chains. The brand, initially just a license to Abril Group, introduces the segmentation media concept on TV channels, even before the introduction of cable TV in Brazil. In 1996, Viacom adopted aggressive global expansion plans. MTV Brazil Ltda is created in a partnership with Abril. After 1999, MTV Networks adopted the slogan Thinks Globally, Acts Locally appropriated to the new expansion strategy. On a counterpart, the Brazilian MTV franchisee reformulated the programmee policy, focusing the non-musical shows in the schedule, in an attempt to increase regional audience. MTV format and the way the network develops, became the brand MTV in one of the greatest symbols of the enculturation imposed by globalization, in the search for a balance between the primary productive manners in the renowned Third World, with the high technology of the "Speed World". The question that emerges is how Brazilian market embodies this new technology taking MTV's Brazil trajectory and analyzing the real contribution of international brands for Brazilian media segment.

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