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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

Concerning the transition of learning : A case study of the LMS and e-learning situation at university department level

Rådemar, Joakim January 2016 (has links)
Uppsala University (UU) is a complex institution, which combines geographically disparate campuses, as well as distance education programs and metropolitan sites for international students. Like many other universities, UU is currently reviewing its e­learning and Learning Management Systems (LMS) situation. In effect, signalling the desire for a strategic change in the future management of learning and teaching arrangement. This thesis analyzes UU’s strategic position and current drivers of change from a LMS and e­learning perspective. Conclusions drawn on the results suggests both retarding and accelerating measure for effective LMS and e­learning engagement. The author contend that adoption of a LMS systems is likely to enhance an e­learning situation if engaged with indicated drivers of change. Illuminating potential LMS transition process, including summation for the upcoming transition.
32

Performance Evaluation Of Vapour Compression System With Environment Friendly Refrigerant Mixtures

Nannaware, Ajay S 08 1900 (has links) (PDF)
No description available.
33

Novo modelo de coeficiente de atividade : F-SAC

Gerber, Renan Pereira January 2012 (has links)
Atualmente, pelo menos para fins de engenharia, os modelos preditivos de maior sucesso para coeficientes de atividade são os baseados em grupos funcionais, tais como UNIFAC e suas variantes. Enquanto esses modelos requerem grandes quantidades de dados experimentais, os baseados em COSMO-RS (COnductor-like Screening MOdel - for Real Solvents) requerem a calibração de um pequeno conjunto de parâmetros universais. No entanto, a precisão requerida por tarefas de engenharia, tais como a otimização de sistemas de separação, é maior do que a obtida por esta última categoria de modelos. Assim, um novo modelo é proposto neste trabalho, aqui chamado de F-SAC (Functional-Segment Activity Coefficient). Este novo modelo também é baseado no conceito de grupos funcionais, mas a energia de interação entre os grupos vem da teoria COSMO-RS. No presente trabalho, foram consideradas apenas misturas em que não há formação de ligação de hidrogênio ou quando esta pôde ser assumida negligenciável. Assim, foram necessários apenas três parâmetros para descrever cada grupo funcional. A princípio, uma vez ajustados os parâmetros de cada grupo, estes funcionariam para descrever a interação para qualquer par de grupos. Esta é a principal vantagem do modelo proposto. O número de parâmetros do modelo cresce proporcionalmente ao número de grupos funcionais, enquanto que no UNIFAC o número de parâmetros de interação cresce proporcionalmente ao quadrado do número de grupos. Para o banco de dados experimentais de coeficientes de atividade em diluição infinita considerado, a correlação do F-SAC apresentou um erro médio absoluto de 0,07 unidades de ln, enquanto que os modelos UNIFAC (Do) e COSMO-SAC apresentaram, respectivamente, erros de 0,12 e 0,21. O F-SAC foi também avaliado para mais de 1000 misturas binárias de um soluto dissolvido em líquido iônico com dados disponíveis na literatura. O modelo apresentou uma boa correlação aos dados experimentais, com erro médio absoluto de 0,17 unidades de ln, similar ao apresentado pelas misturas orgânicas. O poder de predição do novo modelo foi avaliado utilizando dados de equilíbrio líquido-vapor não considerados no procedimento de ajuste do modelo. Uma ótima concordância com os dados experimentais foi possível em toda a faixa de composição, bem como na predição de azeótropos. Esses resultados demonstram o potencial do modelo proposto. / At present, at least for engineering purposes, the most successful predictive models for activity coefficients are those based on functional groups, such as UNIFAC and its variants. While these models require large amounts of experimental data, the ones based on COSMO-RS require the calibration of a small set of universal parameters. However, the resolution required by engineering tasks, such as the optimization of separation systems, is higher than that obtained by COSMO-RS models. Thus, in this work a novel Functional-Segment Activity Coefficient (F-SAC) model is proposed. This new model is also based on the concept of functional groups, but the interaction energy between groups comes from the COSMO-RS theory. In this study, we considered only mixtures where there is no formation of hydrogen bonds or when they could be assumed negligible. Then, only three parameters were required to describe each functional group. In principle, once the parameters for each functional group are properly calibrated, they should work to describe the interactions with any other group. This is the main advantage of the proposed model, the number of model parameters grows linearly with the number of functional groups, whereas in UNIFAC the number of interaction parameters exhibit quadratic growth with respect to the number of groups. For the experimental database of infinite dilution activity coefficients considered, the correlation of F-SAC have shown a mean absolute error of 0.07 ln-unit. The UNIFAC (Do) and COSMO-SAC models presented errors of 0.12 and 0.21, respectively. F-SAC was also evaluated for more than 1000 binary mixtures of solute in ionic liquid with data available in the literature. Again, the model have shown good correlation to the experimental data, with mean absolute error of 0.17 ln-unit, similar to the performance with the organic mixtures. The predictive strength of the model was assessed by using vaporliquid equilibrium data not considered in the model fitting process. Very good agreement with experimental data was possible over the entire composition range, as well as in the prediction of azeotropes. These results demonstrate the potential of the proposed method.
34

Vapor-liquid-equilibria of fuel-nitrogen systems at engine-like conditions measured with Raman spectroscopy in micro capillaries

Klima, Tobias C., Braeuer, Andreas S. 21 December 2020 (has links)
A fuel, here ethanol or decane, and nitrogen are fed at elevated pressure and temperature through a micro capillary of fused silica. The flow inside the capillary is characterized by alternating liquid- and vapor-phase segments that accommodate to thermodynamic equilibrium at the set temperature and pressure. The composition of the equilibrated liquid or vapor segments is measured in situ and remotely inside the micro capillary by Raman spectroscopy. Temperature-composition (Tx) vapor-liquid equilibria were measured for pressures between 3 MPa and 8 MPa and up to the highest mixture critical temperature of 593 K in this pressure range. Comparison to the scarce literature data for these conditions and to the GERG-2008 model, resembling the conditions in IC-engines at the time of injection, is shown.
35

CROSS-PLATFORM FORCE FIELD DEVELOPMENT BASED ON FORCE-SMOOTHED POTENTIAL MODELS

Razavi, Seyed Mostafa 15 July 2020 (has links)
No description available.
36

EVALUATING COSMO-RS FOR VAPOR LIQUID EQUILIBRIUM AND TURBOMOLE FOR IDEAL GAS PROPERTIES

Gazawi, Ayman January 2007 (has links)
No description available.
37

Negotiating Space: Exploring the Rhetorical Potential of Open Source Software

Beerline, Nora 16 May 2011 (has links)
No description available.
38

Online teaching practices : Sociomaterial matters in higher education settings / Undervisningspraktiker online : Ett sociomateriellt perspektiv på högre utbildning

Bolldén, Karin January 2015 (has links)
The aim of this study was to describe and analyse online teaching practices in the Swedish higher education context. The study had an online ethnographic approach and was based on empirical data on the teaching in two university courses. The study rested primarily on observational data but interviews and available documents also formed the basis for analysis. Empirical data were analysed with a perspective of practice theory – a perspective within a sociomaterial account. The results showed that online teaching was characterised by an embodied sociomaterial practice. The teacher’s body could be understood as both multiple and closely interwoven with technology. Furthermore, the teacher’s body was used in the teaching situation to reduce technological complexity but also, along with other forms of materiality, to prefigure what kind of teaching would take place. Teacher interventions in online environments could furthermore be understood as relational to both technology (that is the virtual material arrangement) and teachers’ doings and sayings (that is the teaching practice). Teacher interventions were aimed at making the arrangement intelligible for the students. The study showed that teacher interventions arranged both students and information and communication technology (ICT) in order to make them work as a teaching practice. The teaching practice that emerged was characterised as an interplay between virtual materiality and social practice, where asymmetricrelations between teachers and the ICT prevailed. / Syftet med föreliggande studie var att beskriva och analysera undervisningspraktiker online i svensk högre utbildningskontext. Studien har en onlineetnografisk ansats och baseras på empiriska data av undervisningen i två kurser på universitetsnivå. Studien stödjer sig främst på observationsdata men även intervjuer och dokumentstudier ligger som grund för analysen. Empiriska data har analyserats med ett praktikteoretiskt perspektiv – ett perspektiv inom sociomateriell teoribildning. Resultatet visar att undervisning online kännetecknas av en förkroppsligad sociomateriell praktik. Lärarkroppen kan förstås som både multipel och tätt sammanvävd med teknologi. Vidare används lärarkroppen i undervisningssituationen för att reducera komplexitet men även för att, tillsammans med annan materialitet, prefigurera vad det är för typ av undervisning som kommer att utspela sig. Vidare kan lärarinterventioner i onlinemiljöer förstås som relationella till både tekniken (det vill säga det virtuellt materiella arrangemanget) och lärares göranden och säganden (det vill säga undervisningspraktiken). Lärarinterventioner syftar till att göra arrangemanget begripligt för studenterna. Studien visar att lärarinterventionerna arrangerar både studenter och informations- och kommunikationsteknologi (IKT) i syfte att få dem att fungera som en undervisningspraktik. Den undervisningspraktik som uppstår är inte given på förhand utan emergent. Den karaktäriseras av ett samspel mellan virtuell materialitet och social praktik där asymmetriska relationer mellan lärare och IKT råder.
39

Sistemática para o desenvolvimento de diretrizes no design de interfaces gráficas em tablet PCs voltadas a usuários típicos

Kulpa, Cínthia Costa January 2017 (has links)
A evolução das tecnologias móveis ampliou significativamente a possibilidade de inclusão digital das pessoas com deficiências em geral, permitindo a interação sem as barreiras de espaço e tempo. Dentre estas novas tecnologias está o tablet PC, considerado atualmente a tecnologia móvel mais implementada em instituições de ensino do mundo, devido à sua ampla capacidade de interatividade, flexibilidade, mobilidade, navegação pelos Ambientes Virtuais de Aprendizagem (AVAs), e acessibilidade de diferentes perfis de usuários. Entretanto, a maioria dos usuários com baixa visão (BV) tem encontrado dificuldades em navegar nos AVAs por meio desta tecnologia, tendo que fazer uso de Tecnologias Assistivas voltadas para os cegos. Muito embora as diretrizes utilizadas para a construção destas Interfaces Gráficas do Usuário (GUIs) baseiem-se nos preceitos do W3C e do Design Universal, este fato pode prejudicar sua condição, gerar frustração e, consequentemente, resultar na sua exclusão digital. Com isso, o objetivo desta pesquisa é melhorar as condições de usabilidade dos AVAs no tablet PC, através de uma sistemática estruturada que forneça diretrizes capazes de orientar os desenvolvedores a criarem GUIs pensando no usuário com BV. A metodologia utilizada baseou-se no AVA Moodle como cenário de uso para o estudo de caso, foi realizada em três etapas que incluíram especialistas web, assim como usuários com BV, levando ao desenvolvimento da sistemática. Como resultado final da sua validação, tem-se um Guia de Diretrizes voltado para a construção de GUIs acessíveis aos usuários com BV, no tablet PC. Conclui-se que esta sistemática possibilita ao desenvolvedor agrupar e conceber suas próprias recomendações, em forma de guia de diretrizes, capazes de orientá-lo no incremento de interfaces voltadas especificamente para um usuário típico definido, independente do cenário de uso estabelecido. Refletindo, desta forma, na garantia e qualidade de acesso deste usuário, e permitindo a melhoria do processo de implementação de projetos pelo desenvolvedor. / The evolution of mobile technologies has significantly broadened the digital inclusion possibility for persons with general disabilities, by providing interaction with no space and time barrier constraints. Among these new technologies, the Tablet PCs are currently deemed the most widely implemented mobile technology in teaching institutions worldwide due to their wide capacity of interactivity, flexibility, mobility, browsing through Virtual Learning Environments (VLEs), and accessibility to different user profiles However, most Low Vision (LV) users have faced difficulties to browse through VLEs by means of this technology and must resort to Assistive Technologies aimed at blind persons. Although the guidelines employed for the construction of those Graphic User Interfaces (GUIs) are founded on the precepts of W3C and Universal Design, this fact may harm their condition, generate frustration and, consequently, result in their digital exclusion. This way, the objective of this research is to improve the VLE usability conditions on Tablet PCs through a structured systematic to provide guidelines capable of instructing developers to create GUIs with LV users in mind. The methodology employed is based on the VLE Moodle as the scenery used for the case study, was carried out in three stages and included Web experts as well as LV users, leading to the development of the systematic. As an end result of its validation, there is a Guidelines Guide aimed at the construction of GUIs that are accessible to LV users on Tablet PCs. It has been concluded that this systematic allows developers to group up and conceive their own recommendations in the form of a guidelines guide that are capable of instructing them in incrementing interfaces specifically aimed at a defined typical users regardless of the established scenery of use. This way, it would reflect as an access guarantee and quality for those users, and allow for improvements to the project implementation process by developers.
40

Worthy Worlds: A Case Study of the Pedagogy, Design, and Execution of Two University Courses in Second Life

Fekete, Daniel James 28 November 2012 (has links)
With increasing access to powerful computer processing and broadband Internet connectivity, persistent immersive worlds like Second Life are being adopted for use as virtual learning environments. The flexibility of these spaces, however, offers little innate direction for educators in terms of design and pedagogy considerations, creating a space for research, shared experience, and possibly the development of “best practices” literature. This multiple-case study explores the unique affordances of immersive environments for distance education with reference to the design, pedagogy, and student experience of two university-accredited courses taught entirely “in-world” on the Second Life platform.

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