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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.
31

Satellite Ground Station Cost/Performance Appraisal

Massey, David E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The proliferation of Low Earth Orbiting (LEO) science, earth resources and eventually global communications satellites either in orbit or planned, requires a much lower cost methodology for ground support. No longer is it economically feasible to consider a single, dedicated satellite tracking station to service a LEO spacecraft. An innovative approach is needed to lower the cost of LEO satellite data services thus contributing to the expansion of the commercial space market. This appraisal will cover the performance aspects needed for LEO tracking support and offer a unique and new solution to providing TT&C and payload services.
32

Reviewing Chanel : a catalogue raisonné and critical survey of the dress designs by Chanel published in British and French Vogue, 1916-1929

Holt, Alexia January 1997 (has links)
Founded on the premise that the existing literature on Gabrielle ‘Coco’ Chanel does not give a comprehensive, balanced and objective survey of the dress designs produced by the house from 1916-1929, the thesis ‘Reviewing Chanel’ provides a catalogue raisonné of the designs shown in British and French Vogue during this period. This representative sample of Chanel’s work facilitates the very necessary and overdue re-assessment of Chanel’s early career and contribution to twentieth century fashion. Part One of the Introduction includes a review of the existing literature on Chanel and explains the rationale behind the production of a catalogue of the dress designs reproduced in British and French Vogue. Part Two serves as the introduction to the twenty-eight essays which outline the principal developments in each of the dress design collections presented by the house between 1916-1929. Each essay provides an analytical summary of the key themes and developments of the collection and relates Chanel’s work to that of the other leading houses in Paris during this period.
33

Search for the Standard Model Higgs boson produced in association with a pair of top quarks and decaying into a bb-pair in the single lepton channel at sqrt{s} = 8 TeV with the ATLAS experiment at the LHC

Serkin, Leonid 03 August 2016 (has links)
No description available.
34

Investigation Into Adaptive Structure In Software-embedded Products From Cybernetic Perspective

Yurdakul, Ertugrul Emin 01 May 2007 (has links) (PDF)
This study investigates the concept of adaptivity in relation to the evolution of software and hence software embedded products. Whilst laying out the benefits of adaptivity in products, it discusses the potential future threats engendered by the actual change observed in the functionality principles of adaptive products. The discussion is based upon cybernetic theory which defines control technology in the 20th century anew. Accordingly, literature survey on cybernetic theory, evolution of software from conventional to adaptive structure is presented. The changes in the functionality principles of adaptive systems and the similarities that these changes show with living autonomous systems is also investigated. The roles of product and user are redefined in relation to changing control mechanisms. Then, the new direction that the conventional product-user relationship has taken with adaptive products is examined. Finally, the potential future threats this new direction might bring is discussed with the help of two control conflict situations.
35

The Role Of Design Attributes In Shaping Users

Gedikli, Damla 01 February 2011 (has links) (PDF)
Users evaluate and assign value to products regarding several factors, one of which is design attributes. The attributes can provide certain consequences, which can, in turn, serve to users&rsquo / desires or ultimate goals in life. Value is attributed regarding the desirability of the sequential chain of attributes, consequences and goals. Considering value creation for the users as designers&rsquo / main responsibility / they should focus on how these chains are shaped while designing products. This study mainly concentrates on this relation between design attributes, the consequences these attributes provide, and the ultimate goals of users these consequences satisfy. Three main types of consequence and user goals, which are together called as value types, are identified in the literature: pragmatic, experiential and symbolic. How these value types can be provided by design attributes is examined both with literature review and a research on users&rsquo / pre-purchase value assignment to portable digital audio players. The research on portable digital audio players is conducted using laddering technique. After the interviews with 30 respondents, the value types identified in the literature review as pragmatic, experiential and symbolic value are supported by the data / and and an extension is suggested within the subgroups of experiential value. The salient design attributes that are valued at pre-purchase, and outstanding relations between designed attributes, consequences and user goals are identified.
36

Preschool Children As A User Group: Design Considerations For Musical Toys

Suner, Sedef 01 February 2012 (has links) (PDF)
Early musical experiences are very important for social, cognitive and physical development of children, as well as their future musical competences. Preschools present this environment with various musical materials. However, suitability of these materials in terms of developmental needs of children and educational goals is questionable. The purpose of this study is to transfer knowledge from relevant literature to design considerations of musical toys for preschool children. Literature review was conducted to determine various aspects to be considered while designing musical toys by compiling knowledge from developmental psychology and pedagogy literature / governments
37

Stratégies de synthèse d'azafenestradiènes et d'azacyclooctatriènes / Strategies for the synthesis of azafenestradienes and azacyclooctatrienes

Siby, Acetou 17 February 2012 (has links)
Nous avons étudié des accès possibles à de deux nouvelles familles de molécules qui sont les azacyclooctatriènes et les [6.4.6.4] azafenestradiènes en utilisant une nouvelle méthodologie de synthèse : la réaction d’azaélectrocyclisation à huit électrons π, qui à notre connaissance n’a jamais été décrite à ce jour. Après quelques étapes de synthèse initiées par la réaction de cyclocarbopalladation 4-exo-dig, nous avons pu accéder à différents intermédiaires clés tels que les azatriènynes et les azatétraènes qui nous ont permis d’étudier la faisabilité de la réaction d’azaélectrocyclisation. Différents paramètres ont été étudiés, notamment les conditions de température, l’ajout de métaux de transition en quantité catalytique ainsi que l’introduction de groupements électroattracteurs sur les différentes positions du squellette de l’azocine. Cette étude nous a permis d’établir quelques paramètres utiles à la poursuite de la mise au point de la réaction d’azaélectrocyclisation. / We have studied possibles access to two new molecular families that are azacyclooctatrienes and [6.4.6.4]azafenestradienes by using a new synthesis methodology : the 8π azaelectrocylization which, for now has never been described to our knowledge. After few synthetic steps initiated by the 4-exo-dig cyclocarbopalladation, we have obtained different key intermediates as azatrienynes and azatetraenes in order to study the feasibility of the azaelectrocyclization. The influence of differents parameters have been studied in particular the temperature, catalytic addition of transition metal and the introduction of an electron-withdrawing group in different position of the azocine skeleton. By this study, we established some useful parameters to continue the understanding of azaelectrocyclization feasibility.
38

Självreglerat lärande och motivation i olika typer av idrotter: En jämförelse

Kamp, Patrik, Steneskog, Axel January 2020 (has links)
Självreglerat lärande är en metakognitiv process som visat sig främja idrottares prestation och utveckling. En förutsättning för denna process är att idrottare känner motivation till att utvecklas inom sin idrott. Hur självreglerat lärande och motivation korrelerar samt eventuella skillnader mellan lagidrottare och individuella idrottare avseende självreglerat lärande och motivation är dock relativt outforskade områden. Således var syftet med föreliggande studie att undersöka detta närmare. I studien användes ett teoretiskt ramverk baserat på Self-Regulated Learning (SRL) samt Self Determination Theory (SDT) för att undersöka dessa områden hos 102 tävlingsaktiva idrottare mellan 18-30 år (M = 23,71, SD = 3,77) i deras träningsvardag. Data samlades in genom två elektroniska självskattningsformulär: The Behavioral Regulation in Sport Questionnare (BRSQ-24) och Self-Regulated Learning-TT (SRL-TT). Variansanalyser genomfördes för att undersöka eventuella skillnader avseende SRL och motivationsform mellan respektive grupp. Korrelationsanalyser genomfördes för att undersöka sambanden mellan SRL och motivationsform.  Resultaten visade att individuella idrottare skattade en signifikant högre användning av samtliga SRL-strategier än lagidrottare, medan grupperna inte skiljde sig signifikant gällande motivationsform. Vidare var sambandet mellan autonom motivation och samtliga SRL-faser signifikant positivt för hela urvalet. Resultaten kan förklaras av att det inom individuella idrotter är mer naturligt att använda självreglerat lärande samt att idrottares motivationsform och i vilken utsträckning de använder sig av SRL-strategier korrelerar. Framtida forskning kan med fördel undersöka på vilket sätt idrottares motivationsform och SRL påverkar varandra.
39

Photo-physical Characterization of Donor-Acceptor Systems using Ultrafast Laser Spectroscopy

Alsam, Amani A. 11 1900 (has links)
In donor-acceptor systems, ultrafast interfacial charge transfer (CT), charge separation (CS) and charge recombination (CR), are among the key factors in determining the overall efficiency of the optoelectronic devices. In this regime, precise knowledge of the mechanisms of these processes on the femtosecond scale is urgently required. In this dissertation, using femtosecond transient absorption and mid-Infrared spectroscopies along with steady-state absorption and emission measurements, we are not only able to address the fundamental understanding of these ultrafast dynamical processes, but also control them at various inter- and intramolecular electron donor-electron acceptor systems. In the photoinduced intermolecular charge transfer systems, where donor and acceptor are separated from each other, three systems have been investigated; cationic poly[(9,9-di(3,3′-N,N′-trimethylammonium) propyl fluorenyl-2,7-diyl)-alt-co-(9,9-dioctyl-fluorenyl-2,7-diyl)] diiodide salt (PFN) conjugated polymer donor with 1,4-dicyanobenzene (DCB) acceptor, negatively charged porphyrin (POS) donor with positively charged (PFN) acceptor, and finally, positively charged (PFN) donor with negatively charged graphene carboxylate (GC) acceptor. Based on studying these three systems, we were able to explore some important factors and deriving forces including chemical structure, electrostatic interactions, energy band alignment, hydrogen bonding and solvents with different polarities and capabilities for hydrogen bonding that influence the rate and efficiency of the charge transfer at the interfaces of these donor-acceptor systems. For instance, unlike the conventional understanding of the key role of hydrogen bonding in promoting the charge-transfer process, our results reveal that the hydrogen-bonding increases the spacing between the donor and acceptor units which significantly hinders the charge-transfer process. On the other hand, in the photoinduced intramolecular charge transfer systems, where donor and acceptor are chemically attached to each other, we investigate the effects of conjugation length on photoinduced charge transfer in π-conjugated oligomers naphthalene diimide (NDI) end-capped oligo(phenylene ethynylene)s (PEn-NDI), and poly-(phenylene ethynylene) (PPE) donor backbone with (NDI) acceptor end-caps (PPE-NDI-n) systems. The results of femtosecond transient absorption and mid-IR spectroscopies show that the charge separation occurs on the 1-10 ps time scale with the rates decreasing as oligomer length increases in PEn-NDI system. In addition, in PPE-NDI-n system, the fluorescence quenching measurements indicate very efficient photoinduced electron transfer from the PPE backbone to the NDI end-groups, and the transfer efficiency increases with decreasing the number of units. Finally, the new physical insights reported in this thesis provide an understanding of several key variable components involved, thus paving the way toward the exploitation of efficient charge transfer at donor-acceptor interfaces, which is the key element and urgently required for optimal optoelectronic-device performance.
40

Nyhetssveket från TT : En kvantitativ innehållsanalys av TT:s rapportering från norr / The news betrayal from TT : A quantitative content analysis of TT's news reporting from the north

Nilsson, Felicia, Elebro, Rebecca January 2021 (has links)
Title: The news betrayal from TT – A quantitative content analysis of TT’s news reporting from the north In the year of 2013 TT-nyhetsbyrån closed down their three local editorial offices in north Sweden with a promise that the news coverage of Norrland would remain the same. In this study we aim to examine if, and how, the journalistic content has changed due to their centralization.  Based on theories of media and democracy, the commercialization of journalism and news evaluation, this study investigates different aspects of TT’s journalistic output such as news outlets, news topic, democratic value dimensions, framing, original reporting and sourcing.  The material of examination consists of a total of 199 articles which derive from Luleå, Umeå and Sundsvall. Further the material is spread out over two periods of time. More particularly five years before, and five years after the close down. We have employed a so-called synthetic week during both time intervals, meaning that you randomly select Monday one week, Tuesday the following week, and so forth.  The result of the quantitative study showed that TT’s news reporting about the municipalities has decreased in all the aspects that have been investigated. The analysis of the result, together with previous research and chosen theories, indicates that TT seems to have become more commercialized and audience-oriented, which may have affected how news is valued. From a democratic perspective it is problematic. As the largest news agency TT plays an important role in Swedish journalism, not least when editorial offices around the country reduce their own news coverage.

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