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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

Translation of Heterogeneous High-level Models to Lower Level Design Languages

Jackson, Brian Aliston 04 May 2005 (has links)
Proceeding from a specification, one develops an abstract mathematical model of a system, or portion of a system. This model of a system is validated to insure that the specification is interpreted accurately and to explore different algorithms for implementing the system behavior. We use the words "portion of a system," because only rarely are systems designed wholly using a purely top-down approach. Commonly, the design approach is a mixture of top-down and bottom-up. But even in this mixed approach, top-down techniques are critical to the development of new, advanced system features and improving the performance of existing system components. An example of this style of design tools and environments is Ptolemy II. Ptolemy II is a high-level modeling tool created at UC-Berkeley. It supports heterogeneous and homogeneous modeling, simulation, and design of concurrent systems. High-level modeling of such embedded systems as digital electronics, hardware, and software can be effectively represented. The bottom-up design approach exploits design reuse to achieve the productivity necessary to build complex systems. Historically, chip design companies have always reused designs in going from one product generation to another, but the efficiency of bottom-up design is enhanced by the use of IP (Intellectual Property) cores that a company can buy from an outside source. Design libraries are useful for system design and are an example of IP cores. A sound methodology to translate Ptolemy models to SystemC models would have a very beneficial effect on the CAD/EDA industry. Ptolemy II is written in Java and its high-level designs, or abstract graph models, are represented as XML documents. Ptolemy's major emphasis is on the methodology for defining and producing embedded software together with the system in which it is embedded. SystemC is written in C++, and its industrial use is gaining momentum due to its ability to represent functionality, communication, software, and hardware at various levels of abstraction. SystemC produces synthesizable code. A methodology to convert Ptolemy models to synthesizable SystemC code would be the technical epitome of a hybrid between top-down and bottom-up design styles and methodologies. Such a methodology would enable system designers to obtain fast design exploration, efficient IP-reuse, and validation. Ptolemy has various components and models of computation. A model of computation dictates how components interact between other components. SystemC has its own models of computation and design libraries. XML and Perl are both powerful tools by themselves, and we use these tools in this research to create a sound methodology for translating Ptolemy models (high-level of abstraction) to synthesizable SystemC code (low-level of abstraction), i.e.: code which can serve as input to hardware tools. / Ph. D.
32

Preparation of hydrocortisone nanosuspension through a bottom-up nanoprecipitation technique using microfluidic reactors.

Ali, Hany S.M., York, Peter, Blagden, Nicholas 22 June 2009 (has links)
No / In this work, the possibility of bottom-up creation of a relatively stable aqueous hydrocortisone nanosuspension using microfluidic reactors was examined. The first part of the work involved a study of the parameters of the microfluidic precipitation process that affect the size of generated drug particles. These parameters included flow rates of drug solution and antisolvent, microfluidic channel diameters, microreactors inlet angles and drug concentrations. The experimental results revealed that hydrocortisone nano-sized dispersions in the range of 80¿450nm were obtained and the mean particle size could be changed by modifying the experimental parameters and design of microreactors. The second part of the work studied the possibility of preparing a hydrocortisone nanosuspension using microfluidic reactors. The nano-sized particles generated from a microreactor were rapidly introduced into an aqueous solution of stabilizers stirred at high speed with a propeller mixer. A tangential flow filtration system was then used to concentrate the prepared nanosuspension. The nanosuspension produced was then characterized using photon correlation spectroscopy (PCS), Zeta potential measurement, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and X-ray analysis. Results showed that a narrowsized nanosuspension composed of amorphous spherical particles with a mean particle size of 500±64 nm, a polydispersity index of 0.21±0.026 and a zeta potential of ¿18±2.84mVwas obtained. Physical stability studies showed that the hydrocortisone nanosuspension remained homogeneous with slight increase in mean particle size and polydispersity index over a 3-month period.
33

Från top down till bottom up : - Att förklara och utvärdera psykosocialt arbete inom hälso- och sjukvården

Landpers, Håkan January 2010 (has links)
Today, activities funded with public funds needs to present relevant and reliable information which shows the results obtained. Requirements increase in welfare activities to be run based on scientific, empirical knowledge. This applies particularly to social work. The social work is, however, poorly researched in areas such as knowledge of interventions in the content, context and effects. One way to evidence-base social work can be to conduct regular and qualified assessments. To evaluate, however, is complex, and knowledge of the evaluations are deficient in those who plan and execute them. The overall aim of this study was to conduct a systematic literature review to identify key evaluation models to the psychosocial work in health care services. A further aim was to develop an evaluation design for the psychosocial work of kuratorsenheten, Falun Hospital. The evaluation models are presented in the paper based on categories of “top down” and “bottom up ", and" other models ". With the help of some key concepts for the evaluation of social work, the conclusion of the meta-theory of critical realism, conducted the study analysis. The results show that the models relevant to the evaluation of psychosocial work in the health services are mainly oriented towards a bottom up perspective. The models are process evaluations, user-oriented models, stakeholder assessments, self assessments, and goals - performance evaluations. The evaluation design of kuratorsenheten also presents a number of elements in the psychosocial work which is central to document, for the opportunity to explain, evaluate and develop the business forward.
34

Läs- och skrivinlärning via dator hos elever i årskurs 1

Bjuggren, Maja, Carlsson, Jenny, Nordenberger, Linda January 2011 (has links)
Den formella läs- och skrivundervisningen i Sverige inleds i årskurs 1. Hur läs- och skrivundervisning bedrivs kan skilja sig åt mellan olika klasser. Trageton (2005) har utvecklat en läs- och skrivinlärningsmetod där inlärningen sker via dator. Syftet med föreliggande studie var att undersöka och utvärdera hur ett antal läs-, skriv- och språkförmågor påverkas av Tragetons läs- och skrivinlärningsmetod via dator jämfört med traditionell läs- och skrivinlärning. I studien deltog totalt 26 elever i årskurs 1 på en skola i Östergötland. Datorklassen utgjordes av 13 elever i en klass med läs- och skrivinlärning via dator. Kontrollgruppen utgjordes av 13 elever i en klass med traditionellt läs- och skrivinlärningssätt. Grupperna testades med ett flertal läs-, skriv- och språktest på hösten och våren. Resultaten visade att datorklassen hade fler antal deltagare som kvalificerade sig för testning av läsning på samtliga nivåer. Resultaten på skrivtest visade att kontrollgruppen hade bättre läsbarhet av handstil medan datorklassen var bättre på skriftligt berättande på dator. Resultaten indikerar att båda inlärningssätten har effekt på läs- och skrivinlärningen hos elever i årskurs 1 och att vart och ett av inlärningssätten stärker olika förmågor inom läsning och skrivning. / Formal literacy education in Sweden begins in first grade. How reading and writing education is conducted may differ between classes. Trageton (2005) has developed a literacy learning method in which the computer plays a significant role. The aim of this study was to examine and evaluate how a number of literacy and language abilities are affected by computer based literacy learning developed by Trageton, compared to traditional literacy learning. In the present study, 26 students in first grade from a school in Östergötland participated. The computer based group consisted of 13 students who attended a class in which computer based literacy learning was used. The control group consisted of 13 students who attended a class in which traditional literacy learning was used. A number of literacy and language tests were administrated in both fall and spring time. The results showed that more participants in the computer based group, than in the control group, qualified for reading tests at all levels. The results in the writing test showed that the control group performed better in handwriting while the computer based group performed better in written narratives on the computer. The results of the present study indicate that both literacy learning methods have an effect on reading and writing skills in students in first grade. The results also indicate that each of the learning methods improve various reading and writing skills.
35

Atenção visual bottom-up guiada por otimização via algoritmos genéticos. / Attention-oriented bottom-up visual optimization via genetic algorithms.

PEREIRA, Eanes Torres. 31 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-31T14:31:59Z No. of bitstreams: 1 EANES TORRES PEREIRA - DISSERTAÇÃO PPGCC 2007..pdf: 4422108 bytes, checksum: 9b27a661074ca88e823ffb0472a68502 (MD5) / Made available in DSpace on 2018-07-31T14:31:59Z (GMT). No. of bitstreams: 1 EANES TORRES PEREIRA - DISSERTAÇÃO PPGCC 2007..pdf: 4422108 bytes, checksum: 9b27a661074ca88e823ffb0472a68502 (MD5) Previous issue date: 2007-03 / A atenção visual é um mecanismo biologicamente inspirado, o qual corresponde à habilidade de selecionar e processar somente as regiões mais relevantes de uma cena visual. Para fins didáticos, a atenção visual pode ser dividida em duas categorias principais: bottom-up e top-down. A atenção visual bottom-up guia o foco de atenção a partir de características primitivas (como descontinuidades de intensidade em diferentes escalas e orientações) computadas diretamente na imagem,sem qualquer informação contextual. A atenção visual top-down, por outro lado, realiza uma busca por regiões de interesse a partir de características de alto nível, especificadas na forma de conhecimento prévio na forma ou modelos sobre o que se está buscando na cena. A principal questão de pesquisa que procuramos responder nessa dissertação é a seguinte: como seria possível agregar algum comportamento de alto nível a um mecanismo típico de atenção visual bottom-up (guiando dessa forma o foco de atenção para classes de regiões pré-estabelecidas)? O modelo mais conhecido de atenção visual bottom-up utiliza vários mapas de características primitivas para formar um mapa de saliência, o qual indica a importância do ponto de vista atencional das diferentes regiões de uma cena. Nesse trabalho, atribuímos pesos aos mapas de características e desenvolvemos um processo de otimização baseado em algoritmos genéticos simulados em uma grade computacional. Foram realizados experimentos com quatro classes de objetos (carros, faces de pessoas, objetos genéricos e pistolas). Os resultados utilizando atenção bottom-up com otimização foram comparados com os resultados de um mecanismo sem otimização de pesos e com um sistema existente que implementa o difundido modelo de atenção visual proposto por Itti et al. [Itti et al., 1998]. Os resultados mostraram ganhos de até 30% utilizando-se a abordagem proposta. Desta forma, este trabalho mostra que a atenção visual pode ser guiada para regiões pré-definidas, podendo ser utilizada como parte de sistemas de detecção de objetos. / Visual attention is a biologically inspired mechanism, which corresponds to the ability of selecting and processing only the most relevant regions of a visual scene. For didactic purposes, visual attention can be divided into two main categories: bottom-up and top down. Bottom-up visual attention guides the attention focus by using primitive visual features (such as discontinuities in intensity across different scales and orientations) computed directly from the input image,without the need of any context information. Top-down visual attention, on the other side, performs a search for interest regions from higher-level features, specified in the form of previous knowledge or models about what is being sought in the scene. Themain research question that we intended to answer in this dissertation was the following: how it would be possible to incorporate some higher-level be haviour into a typical bottom-up visual attention mechanism (thus guiding the attention focus to pre-established classes of objects)? The most known bottom-up visual attention model uses several primitive feature maps to form a saliency map, which indicates the importance of the different scene regions. In this work, we assigned weights to the feature maps and developed an optimization process based on genetic algorithms running on a computational grid. Experiments involving four object classes (cars, human faces, generic objects and pistols)have been performed. The results of the optimized bottom-up mechanism have been compared with the results of a mechanism not using optimized weights and with an existing system that implemented the well known visual attention mechanism proposed by Itti et al. [Itti et al., 1998]. The results have shown an improvement of up to 30% when using the optimized mechanism. Thus,this work shows that visual attention can indeed be guided towards pre-defined regions and can be used as part of object detection systems.
36

ANÁLISE DAS ESTRATÉGIAS BOTTOM-UP EM LIVROS DIDÁTICOS DE PORTUGUÊS PARA ESTRANGEIROS SEGUNDO A TEORIA DA ATIVIDADE / ANALYSIS OF BOTTOM-UP STRATEGIES IN PORTUGUESE FOR FOREIGNERS TEXTBOOKS ACCORDING TO ACTIVITY THEORY

Pinto, Cândida Martins 12 February 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aims at investigating how authors of Portuguese for foreigners textbooks work with the reading ability in relation to the use of the bottom-up strategies. In order to verify how the relation between reading ability and linguistic competence works, I have decided to analyze the reading sections of four Portuguese for foreigners textbooks that are been used nowadays and which contains the teacher s book. First of all and within this context, the methodology of data analysis was based on Leontiev s version of Activity Theory (1977), for the purpose of identifying what actions are developed by the student during the activity of learning Portuguese and checking whether these actions may become operations. Secondly, it was found theoretical support in Richter s Holistic Model (2004, 2005) as a way to describe the reading tasks of those textbooks and elaborate a model of a standard class. This model which was based on an interactive reading teaching and applied to a complex spiral vision, was compared to the corpus of this study, to verify what material would be closer to the ideal one for internalization of specific formal items. The study theoretical support was centered in the following aspects: textbook as a genre; Vygotsky s social-interactionist teaching, emphasizing key-concepts as mediation, internalization and zone of proximal development; Activity Theory, textbook according to Activity Theory; reading and cognition and reading models. The results suggest a tendency of the authors of the analyzed corpus to consider the bottom-up strategies as irrelevant ones for the student to construct the meaning of the text. / Este trabalho tem como objetivo investigar como autores de livros didáticos de português para estrangeiros trabalham a habilidade de leitura no que se refere ao uso das estratégias bottom-up. A fim de verificar como se dá a relação entre habilidade de leitura e competência lingüística, escolhi analisar as seções de leitura de quatro livros didáticos de Português para estrangeiros que possuem livros do professor e estão sendo usados atualmente em sala de aula. Nesse contexto, a metodologia de análise dos dados foi pautada, primeiramente, na Teoria da Atividade na versão de Leontiev (1977), procurando identificar quais são as ações desenvolvidas pelo aluno durante a atividade de aprender Português e se essas ações podem vir a se transformar em operações. Em um segundo momento, buscou-se sedimentação teórica no Modelo Holístico de Richter (2004, 2005), como forma de descrever as tarefas de leitura dos livros e de elaborar um modelo de aula padrão. Esse modelo, embasado a favor de um ensino de leitura interativo, aplicado a uma visão em espiral de complexidade, foi cotejado com o corpus deste estudo, no intuito de verificar qual material estaria mais próximo do ideal para a internalização de itens formais específicos. A fundamentação teórica foi centrada nos seguintes aspectos: livro didático visto como um gênero textual; ensino sócio-interacionista de Vygotsky, ressaltando conceitos-chave como mediação, internalização e zona de desenvolvimento proximal; Teoria da Atividade, livro didático segundo a Teoria da Atividade; leitura, cognição e modelos de leitura. Os resultados obtidos sugerem uma tendência dos autores do corpus analisado a considerar as estratégias bottomup irrelevantes para que o aluno construa o significado do texto.
37

I amSMARTerdam : Revaluating the Smart City concept through the world's most bottom-up Smart City

van den Boogaard, Lucas January 2018 (has links)
Smart Cities are, while hot-and-happening, in the field of urban planning, also a source of confusionand debate. While many argue against the technology-driven and top-down nature of the Smart Citymodel, the bottom-up component is often appointed as the deciding factor in the determinationwhether a Smart City can be successful and contributing to its set goals, or rather resulting in an effortharming the city and its citizens in the long run. This thesis set out to explore the bottom-upcomponent in one of the most revered and most bottom-up Smart Cities of the world, Amsterdam.Remarkably, the research has proven that Amsterdam Smart City, even though it is often seen as oneof the good examples, suffers from the same issues. Its initiatives are an amalgamation of subjectsthat hardly seem to fit under the smart narrative as propagated by Amsterdam Smart City and hardlyany initiatives can be considered truly bottom-up. If one of the prime examples fails to adhere to itsown standards, what does this mean for the concept of smart cities?
38

Görandets rationaliteter. : En kvalitativ studie i vilka rationaliteter som ligger till grund för det politiska handlandet. / The rationalities of doing. : A qualitative study regarding which rationalities constitutes the basis of political action.

Westerholm, Märtha January 2018 (has links)
This bottom-up study argue that making of social politics occurs in the meeting between the citizen and the representative of state. In order to generate a deeper understanding of the production of politics, the aim of this study was to identify expressed motivators and arguments in relation to a specific policy, which would unveil the underlying rationalities of actions taken by the specific actors. The policy was introduced in the Växjö municipality in June of 2017 and has changed the benefit distributed by the social services for immigrants waiting to start an employment program through an employment bureau into a loan.  In-depth interviews study, a total of 9 interviews have been undertaken with; decision-making politicians, public officials working with the policy and service users who have been affected by the policy. The data was processed and analyzed according to themes and to theory on rationality. The results showed that the main rationality forming the actions of politicians and public officials was linked to their ambition of upholding an efficient use of resources for the benefit of municipality economy. The main rationality behind the actions of the service users was to obtain autonomi in their life. An important goal for both parties was that the service users should become self-sustaining. Furthemore, the politicians and public officials clamied the responsibility for goal-fullfilment to realy on the individuals and not on the municipality. In addition, the results of this study has revealed that the way that politicians and public officials´ view immigrants, has affected the framing of the policy, deriving from a paternalistic understanding. Service users in the study expressed eagerness and high motivation towards starting employment. However, service users in this study viewed the loan as a hindrance rather than a support towards accomplishing the goal of employment, thus becoming autonomic.
39

Le développement de l’ambidextrie contextuelle à l’aide d’un outil de gestion : étude de cas exploratoire du Fab Lab interne chez Renault / The development of contextual ambidexterity through a management tool : exploratory case study of Renault's internal Fab Lab

Lo, Amadou 04 December 2015 (has links)
Cette thèse a pour objectif de mieux comprendre et d’accompagner les stratégies d’innovation des entreprises face aux défis liés à l’intensification de la dynamique et des changements de l’environnement économique. Or, afin de survivre à ces rythmes économiques, la littérature préconise aux organisations de concilier leurs activités d’exploitation et leurs activités d’exploration de façon concomitante. Dans ce cadre, notre travail étudie spécifiquement une stratégie d’innovation conférant une importance particulière aux initiatives des individus dans les activités d’exploration : l’ambidextrie contextuelle. Simultanément, notre recherche examine un objet de recherche jusque là inédit dans le milieu académique : le Fab Lab d’entreprise (ou Fab Lab interne). A la croisée des chemins de ces deux sujets, cette thèse pose la question du développement de l’ambidextrie contextuelle à l’aide d’un Fab Lab d’entreprise.L’étude de cas menée au sein de l’une des premières structures à développer cette pratique de Fab Lab d’entreprise – le Groupe Renault – définit cet outil de gestion comme une quasi-structure propice au développement de l’ambidextrie contextuelle. Elle présente ensuite le pilotage à mener afin de développer l’ambidextrie contextuelle à l’aide d’un Fab Lab d’entreprise. / This thesis aims to better understand and support corporate innovation strategies to help them coping with the challenges associated with the intensification of the dynamics and changes in the economic environment. However, in order to survive these economic rhythms, previous research recommends organizations to reconcile their exploitation and their exploration activities, concomitantly. In this context, our work specifically examines an innovation strategy giving particular attention to the initiatives of individuals in exploration activities : contextual ambidexterity. Simultaneously, our research examines an object of research previously unreleased in academic studies : the corporate Fab Lab (or internal Fab Lab). At the crossroads of these two subjects, this thesis raises the question of the development of contextual ambidexterity through a corporate Fab Lab. Our case study is conducted in Renault Group, one of the first structures to develop this practice of corporate Fab Lab. Our analysis permits to define this management tool as a quasi-structure conducive to the development of contextual ambidexterity. It then presents the guidance to lead in the objective of developing contextual ambidexterity through a corporate Fab Lab.
40

Synthesis of Metallic Nanowires Using Integrated DNA Molecules as Templates

Erler, Christiane 23 March 2010 (has links)
The DNA double helix is inherently a nanoscale wire-like object, possessing a 2 nm diameter as well as a remarkable capability for molecular recognition and the interaction with other chemical compounds, thus making it an attractive material for biologically driven assembly of artificial nanostructures. In this work methods for the construction of functional electronic networks from single DNA molecules are presented. For this, (i) the generation of patterns of distinct interconnects between micro-fabricated contact pads are explored by stretching end-specifically thiol-functionalized, single-tethered DNA molecules using hydrodynamic flow as well as an electric field-induced thermal flow. (ii) These networks then serve as a template for a selective in-situ photoinduced nucleation and growth of platinum clusters of 4 nm diameter along the DNA molecules. In the synthesis exclusively platinum ions from an aqueous platinum nitrate solution bonded electrostatically to the backbone of the immobilized DNA can be reduced upon irradiation with UV light, while background metallization is inhibited. Furthermore, the metallization scheme is applied to DNA nanotubes and another photochemical deposition process is used to tune the interparticle gap space in a discontinuous platinum cluster chain to form conducting nanowires. The "process toolbox'' presented in this work offers a versatile alternative for the hierarchical patterning and incorporation of biotemplated nanomaterials into micro-/nanofabrication schemes. / Ein doppelhelikaler DNA-Strang besitzt mit seinem hohen Aspektverhältnis von Natur aus Ähnlichkeit mit einem Kabel. Zusammen mit seinen einzigartigen Selbstassemblierungseigenschaften sowie der Fähigkeit, mit einer Vielzahl von chemischen Stoffen eine Verbindung einzugehen, macht dies ihn zu einem aussichtsreichen Baumaterial für den Aufbau von künstlichen Nanostrukturen. In dieser Arbeit werden deshalb verschiedene Methoden für den Bau von elektronischen Schaltkreisen aus einzelnen DNA-Strängen demonstriert. Dazu wird (i) die Herstellung von Verdrahtungsmustern zwischen lithographisch gefertigten Kontaktstrukturen untersucht. Endständig mit Thiolgruppen funktionalisierte DNA-Moleküle, die an nur einem Ende mit der Oberfläche verknüpft sind, werden mittels Strömung oder eines elektrothermisch induzierten Flusses zwischen Elektroden gespannt. (ii) Diese Netzwerke dienen im Weiteren als Vorlage für ein selektives, lichtinduziertes Wachstum von Platinpartikeln mit Durchmessern von 4 nm lokal entlang der DNA-Moleküle. Dabei werden unter UV-Bestrahlung nur solche Platinionen reduziert, die aus einer Platinnitrat-Lösung elektrostatisch an die immobilisierte DNA angebunden haben. Partikelwachstum in der umgebenden Lösung wird weitgehend verhindert. Darüber hinaus wird dieses Verfahren auch auf DNA-Nanoröhren angewendet und ein weiterer photochemischer Abscheideprozess eingesetzt, um unterbrochene Clusterkettern zusammenzuwachsen, mit dem Ziel, elektrisch leitfähige Nanodrähte zu erhalten. Die vorgestellten Verfahren stellen eine vielseitige Alternative zu herkömmlichen, hierarchischen Fabrikationsschemen der Mikro- und Nanotechnologie dar.

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