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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.
141

On Microscopic Traffic Models, Intersections and Fundamental Diagrams

McGregor, Geoffrey 07 May 2013 (has links)
We design an Ordinary Delay Differential Equation model for car to car interaction with switching between four distinct force terms including "free acceleration'', "follow acceleration'', "follow braking'', and aggressive driving''. We calibrate this model by recreating a real experiment on spontaneous formation of traffic jams. Once simulations of our model match those of the experiment we develop a model of both intersections using traffic lights, and intersections using roundabouts. Using our calibrated car interaction model we compare traffic light versus roundabout efficiencies in both flux and fuel consumption. We also use simulation results to extract information relevant to macroscopic traffic models. A relationship between flux and density known as The Fundamental Diagram is derived, and we discuss a technique for comparing microscopic to macroscopic models. / Graduate / 0405 / gmcgrego@uvic.ca
142

Development of Greenhouse Gas Mitigation Options for Albertas Energy Sector

Subramanyam, Veena 11 1900 (has links)
Alberta is the third largest economy in Canada and is expected to grow significantly in the coming decade. The energy sector plays a major role in Albertas economy. The objective of this research is to develop various greenhouse gas (GHG) mitigations scenarios in the energy demand and supply sectors for the Province of Alberta. This is done through an energy-environment planning and forecasting tool called Long Range Energy Alternative Planning system model (LEAP). By using LEAP, a sankey diagram for energy and emission flows for the Province of Alberta has been developed. A reference case also called as business-as-usual scenario was developed for a study period of 25 years (2005-2030). The GHG mitigation scenarios encompassed various demand and supply side scenarios. In the energy conversion sector, mitigation scenarios for renewable power generation and inclusion of supercritical, ultra-supercritical and integrated gasification combined cycle (IGCC) plants were investigated. In the oil and gas sector, GHG mitigation scenarios with carbon capture and sequestration (CCS) option were considered. In Albertas residential and commercial sector 4-6 MT of CO2 equivalents per year of GHG mitigation could be achieved with efficiency improvement. In the industrial sector up to 40 MT of CO2 equivalents per year of GHG reduction could be achieved with efficiency improvement. In the energy conversion sector large GHG mitigation potential lies in the oil and gas sector and also in power plants with carbon capture and storage (CCS) option. The total GHG mitigation possible in the supply side option is between 20 70 MT CO2 equivalents per year. / Engineering Management
143

Quantifying system reliability in rail transportation in an aging fleet environment

Conradie, Pieter Daniel Francois 03 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In recent years, the management of physical assets has become increasingly important, even more so, in asset intensive organisations. This research work presents an overall approach to quantify reliability of rolling stock assets in the rail environment. The current maintenance management system in the case studied is over-reliant on cancellations and delays as reliability measure. The objectives of this study were, therefore, to develop a scientific approach to quantify the reliability of the rolling stock fleet and to develop a maintenance planning model based on system reliability. The research methodology followed made use of failure statistics, failure distributions and the interdependence of different systems to determine the impact of component failures on the overall system reliability. This could then be used to determine the reliability of individual train sets in order to better understand their performance. The reliability measure could be used for predicting component and train set failures as well as to better understand the contribution of maintenance towards reliability, hence the term Reliability Based Maintenance. The model, validated with real data, illustrates how the reliability measure can be used to determine maintenance intervals of different train sets. Based on the results, recommendations are made in relation to future planning of the maintenance strategy. / AFRIKAANSE OPSOMMING: Die bestuur van fisiese bates het in die afgelope tyd meer belangrik geword, veral in organisasies wat afhanklik is van hulle fisiese bates. Hierdie navorsing stel ‘n metode voor wat die betroubaarheid van rollende materiaal bates in die spoor bedryf kwantifiseer deur gebruik te maak van falingstatistiek. In die huidige instandhouding bestuurstelsel van die gevallestudie word daar te veel gesteun op kansellasies en vertragings van treine as ‘n betroubaarheids meting. Daarom was die doelwitte van die navorsing om ‘n wetenskaplike benadering te ontwikkel om betroubaarheid van rollende materiaal the kwantifiseer, en om ‘n instandhouding beplannings model voor te stel, gebaseer op sisteem betroubaarheid. Die navorsingsmetodologie is gebaseer op falingstatistieke, falingverspreidings, en die interafhanklikheid van stelsels word gebruik om die invloed van komponent falings op die betroubaarheid van die totale stelsel te bepaal. Hierdie benadering word dan gebruik om die betroubaarheid van individuele treinstelle en die werksverrigting van individuele trainstelle te bepaal. Hierdie instandhouding meting kan gebruik word om falings van komponente en treinstelle te voorspel, asook om die bydrae van instandhouding tot betroubaarheid beter te verstaan, daarom genoem Betroubaarheids Gebaseerde Instandhouding. Dit is ook geïllustreer hoe die betroubaarheid meting gebruik kan word om instandhouding intervalle te bepaal. Die betroubaarheid model is met werklike data gevalideer en aanbevelings word gemaak hoe om betroubaarheid te gebruik om die toekomstige beplanning van instandhouding te doen.
144

Figurální myšlení o filmu: teorie a praxe / Figural Thinking: Theory and Practice

Žilová, Jana January 2015 (has links)
! ! Dissertation Abstract ! ! This research presents examination of the figural theory as established by Jean-François Lyotard in his work Discourse, figure (1971). Figural theory groundwork proved to be underpinned within the psychoanalytical framework as in the classical dreamwork and concept of transitional space as elaborated by D. Winnicott. We argue that the specific figural intermediary space defines a type of space that allows the image and the viewer to explore the individuation processes, as established by G. Simondon (1992) and thus create potential new series of the image which instigate and challenge new perceptive patterns of the viewer. Figural backdrop has been detected within the work of Gilles Deleuze, precisely in Logic of Sensation (1981) where Deleuze examines the diagrammatic system. As a result of the in-depth exploration of Lyotardian poetic transgressions as we have applied on the film intertitles we have proved a presence of a specific mobile integral title. This type of inter title brings forth the coalescence of text-image that resurfaces the image's resources. The pictorial transgression was examined on the example of Nicolas Roeg's color- events in Don't Look Now 1973 and the cinematic transgression was explored on the example of William Kentridge' s video work Automatic...
145

Matrix representation for partitions and Mock Theta functions

Bagatini, Alessandro January 2016 (has links)
Neste trabalho, com base em representações por matrizes de duas linhas para alguns tipos de partição (algumas já conhecidas e outras novas), identificamos propriedades sugeridas por classificá-las de acordo com a soma dos elementos de sua segunda linha. Esta soma sempre fornece alguma propriedade da partição relacionada. Se considerarmos versões sem sinal de algumas funções Mock Theta, seu termo geral pode ser interpretado como função geradora para algum tipo de partição com restrições. Para retornar aos coeficientes originais, é possível definir um peso para cada matriz e depois somá-las para contá-los. Uma representação análoga para essas partições nos permite observar propriedades sobre elas, novamente por meio de uma classificação referente à soma dos seu elementos da segunda linha. Esta seriação é feita por meio de tabelas criadas pelo software matemático Maple, as quais nos sugerem padrões e identidades relacionadas com outros tipos de partições conhecidas e, muitas vezes, encontrando uma fórmula fechada para contá-las. Tendo as conjecturas obtidas, elas são provadas por meio de bijeções entre conjuntos ou por contagem. / In this work, based on representations by matrices of two lines for some kind of partition (some already known and other new ones), we identify properties suggested by classifying them according to the sum of its second line. This sum always provides some properties of the related partition. If we consider unsigned versions of some Mock Theta Functions, its general term can be interpreted as generating function for some kind of partition with restrictions. To come back to the original coefficients, you can set a weight for each array and so add them to evaluate the coefficients. An analogous representation for partitions allows us to observe properties, again by classificating them according to the sum of its elements on the second row. This classification is made by means of tables created by mathematical software Maple, which suggest patterns, identities related to other known types of partitions and often, finding a closed formula to count them. Having established conjectured identities, all are proved by bijections between sets or counting methods.
146

Možnosti využití metody kritické cesty

Doležalová, Jana January 2012 (has links)
No description available.
147

Sestavení diagramu syntézy pro stanovení optimální hustoty lesních odvozních cest a jeho aplikace na zadaném gravitační území

Kostka, Michal January 2013 (has links)
No description available.
148

A geometria presente em alguns livros didáticos dos anos finais do ensino fundamental / The geometry in the textbooks of final years of elementary school

Godoy, Juliana Samora [UNESP] 24 February 2016 (has links)
Submitted by JULIANA SAMORA GODOY null (julianasamoragodoy@yahoo.com.br) on 2016-04-06T02:04:38Z No. of bitstreams: 1 Dissertação Juliana.pdf: 2181882 bytes, checksum: 52a7dd3d2f66b95b45706db6b3d17b45 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-07T18:07:27Z (GMT) No. of bitstreams: 1 godoy_js_me_rcla.pdf: 2181882 bytes, checksum: 52a7dd3d2f66b95b45706db6b3d17b45 (MD5) / Made available in DSpace on 2016-04-07T18:07:27Z (GMT). No. of bitstreams: 1 godoy_js_me_rcla.pdf: 2181882 bytes, checksum: 52a7dd3d2f66b95b45706db6b3d17b45 (MD5) Previous issue date: 2016-02-24 / Esta pesquisa tem seu foco na Geometria presente alguns livros didáticos de Matemática, sendo a pergunta diretriz do trabalho: “Como fazer da leitura geométrica dos diagramas uma metodologia de análise para a Geometria presente nos livros didáticos de Matemática?”. O objetivo principal do trabalho é fazer da leitura geométrica dos diagramas uma metodologia de análise dos conteúdos de Geometria existentes em alguns livros didáticos. A coleta de dados se baseia em três coleções de livros didáticos de Matemática dos anos finais do Ensino Fundamental. A análise dos dados é realizada principalmente com base na teoria de leitura geométrica, desenvolvida por Dietiker e Brakoniecki (2014). Essa teoria diz respeito à negociação de significados entre o leitor e o texto escrito, ou seja, é a compreensão que quem está realizando a leitura desenvolve sobre os diagramas. É uma pesquisa de cunho qualitativo. Tem como temas para a análise de dados: a identificação dos diferentes tipos de signos existentes nos diagramas dos livros didáticos analisados, bem como o estudo de propriedades métricas e topológicas de alguns conteúdos presentes nesses livros e a utilização de representações mentais de conceitos geométricos. Os diferentes tipos de signos são identificados de acordo com a teoria dos Signos de Peirce (1931), podendo ser indicadores, ícones ou símbolos, dependendo da definição assumida no texto e também do possível entendimento do leitor. Em meu trabalho, fica evidente que nos anos iniciais do Ensino Fundamental II, principalmente, os autores das coleções de livros didáticos utilizam com frequência os indicadores para introduzir o assunto dos capítulos, e ao aprofundarem tais assuntos passam a se utilizar de ícones e depois formalizam conceitos utilizando-se de símbolos. O estudo de propriedades métricas e topológicas é pautado em Borges (2005), no qual há a assimilação de propriedades métricas com a parte quantitativa dos diagramas, e das propriedades topológicas com a parte qualitativa dos diagramas. Como resultado dessa análise, destaco que as propriedades métricas estão sendo mais utilizadas se comparadas com as propriedades topológicas, pois os autores, de modo geral, se utilizam de diversas marcações nas figuras para exemplificar uma ideia, focando assim nas propriedades métricas das figuras. Por último, o estudo de representações mentais é pautado em alguns autores, como por exemplo, Galperin (1989), que trata destas representações como sendo um processo que se constrói ao longo dos anos escolares. Esse processo de construção de representações mentais é evidenciado com o estudo dos livros, uma vez que tais representações começam a ser necessárias nos livros dos anos finais do Ensino Fundamental. A partir dessas análises, concluo que uma leitura geométrica é repleta de negociações de significados entre o texto e o que o leitor assume dos mesmos, já que são essas negociações que dão suporte para o entendimento do conteúdo. Destaco que ao fazer uma leitura multidimensional dos diagramas, é possível identificar quase todas as suas características relevantes, pois não olhamos especificamente para uma única classificação ou uma única dimensão de leitura, mas sim para grande parte das informações do diagrama, compondo assim a leitura geométrica. / This research focuses on geometry of Mathematics textbooks, and the main question of this work is: "How to read the geometric diagrams a methodology for this geometry in textbooks of mathematics?". The main objective of this study is to make the reading of the geometric diagrams a methodology of analysis of geometry issues in some textbooks. Data collection is based on three collections of textbooks of Mathematics of Primary Education II. The data were obtained from three collections of Mathematics textbooks of Secondary School. Data analysis was made mainly based on theory of geometric reading developed by Dietiker and Brakoniecki (2014). This theory concerns the negotiation of meanings between the reader and the written text, in other words, is the understanding that the reader develops abaout the diagrams. It is a qualitative research which have as themes for data analysis: the identification of the different types of signs in the diagrams of the textbooks analyzed, and the study of metric and topological properties of some contents present in these books and the use of mental representations of geometric concepts. The different types of signs are identified according to the theory of Signs of Peirce (1931), may be indicators, icons or symbols, depending on the assumed definition text and also the possible reader's understanding. In this study is evident that mainly in the early years of Second school, the authors of the textbooks collections often use the indicators to introduce the subject of the chapters, and when deepen such matters come to be used icons and then formalize concepts using symbols. The study of metric and topological properties is guided by Borges (2005), in which there is assimilation from metric properties with the quantitative part of the diagrams and, from the topological properties with the qualitative part of diagrams. As a result of this analysis, we emphasize that the metric properties are being used more as compared with the topological properties, since the authors, in general, use several tags in the figures to illustrate an idea, thus focusing on the metric properties of the figures. Finally, the study of mental representations is guided by some authors, such as Galperin (1989), which deals with these representations as a process that is developed over the school years. This process is evidenced by the study books, since such representations will be necessary in the books of the final years of Secondary school. Based on this analysis, we concluded that a geometric reading is full of negotiations of meaning between the text and what the reader assumes from the same, as are these negotiations that support the understanding of the content. I emphasize that when making a multidimensional reading of diagrams, it is possible to identify almost all the relevant characteristics, for not specifically look at a single classification or a single dimension of reading, but for a big part of the diagram information, composing of this way the geometric reading.
149

Transições de fases estruturais do sistema PZT, estudados por espectroscopia no infravermelho

Paes, César [UNESP] 15 December 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-12-15Bitstream added on 2014-06-13T19:12:25Z : No. of bitstreams: 1 paes_c_me_ilha.pdf: 1124164 bytes, checksum: b30843e958a40bb7c8b7ff4142f19d31 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho tem como objetivo estudar, através de investigações de espectros no infravermelho (FTIR), as transições de fases estruturais do sistema ferroelétrico titanato zirconato de chumbo, PbZr1-xTixO3 (PZT) no Contorno de Fase Morfotrópico (Morphotropic Phase Boundary, conhecido como MPB), região em que as propriedades elétricas desse material são máximas. Foram analisadas as soluções sólidas PbZr0,53Ti0,47O3 e PbZr0,54Ti0,46O3, que à temperatura ambiente encontram-se no interior do MPB e PbZr0,55Ti0,45O3, composição no limite da região do MPB, entre a fase monoclínica e a fase romboédrica, região ainda não bem definida e sob intensa investigação. Estudos estão centrados na freqüência e na meia largura dos modos stretching nos octaedros (BO6) da estrutura perovskita (ABO3) em função da temperatura. Anomalias encontradas para amostras com 47 e 46 mol % de PbTiO3 sugerem as transições da fase monoclínica de baixa para alta temperatura ( LT M F ? HT M F ), da fase monoclínica de alta temperatura para a coexistência da fase monoclínica com a fase tetragonal ( M F ? M F + T F ), e da coexistência da fase monoclínica com a tetragonal para a fase cúbica ( M F + T F ? C F ). Na amostra com 45 mol % de PbTiO3 foram encontradas anomalias que podem também estar associadas às transições de fases, mas que não foram possíveis de serem identificadas nas fases envolvidas. / The present work studies, through investigations of the spectra in infrared (FTIR), the transitions of structural phases of the ferroelectric system lead zirconate titanate, PbZr1- xTixO3 (PZT), in the Morphotropic Phase Boundary (MPB), region where the electrical properties of this material are at its maxiumun. We analyzed the solid solutions PbZr0,53Ti0,47O3 and PbZr0,54Ti0,46O3, which at room temperature are found within the MPB and also the composition PbZr0,55Ti0,45O3, that is located on the limit of the MPB - between the monoclinic and the rhombohedral phases - a not-yet defined region under intense investigation. Studies are concentrating on frequency and half width of the stretching modes in octahedrons (BO6) of the perovskite structure (ABO3) regarding temperature. Anomalies found in samples with 47 and 46 mol % of PbTiO3 suggest transitions in the monoclinic phase from low to high temperature ( LT M F ? HT M F ), from monoclinic phase of high temperature to the coexistence between the monoclinic phase with the tetragonal phase ( M F ? M F + T F ), and the coexistence between the monoclinic phase with tetragonal for the cubic phase ( M F + T F ? C F ). In the sample with 45 % mol of PbTiO3 we have found anomalies that can also be associated with phase transitions. Such transitions have not been possible to identify during the stages of this work.
150

Transições de fases estruturais do sistema PZT, estudados por espectroscopia no infravermelho /

Paes, César. January 2006 (has links)
Orientador: Eudes Borges de Araújo / Banca: Victor Ciro Solano Reynoso / Banca: Sebastião William da Silva / Resumo: O presente trabalho tem como objetivo estudar, através de investigações de espectros no infravermelho (FTIR), as transições de fases estruturais do sistema ferroelétrico titanato zirconato de chumbo, PbZr1-xTixO3 (PZT) no Contorno de Fase Morfotrópico (Morphotropic Phase Boundary, conhecido como MPB), região em que as propriedades elétricas desse material são máximas. Foram analisadas as soluções sólidas PbZr0,53Ti0,47O3 e PbZr0,54Ti0,46O3, que à temperatura ambiente encontram-se no interior do MPB e PbZr0,55Ti0,45O3, composição no limite da região do MPB, entre a fase monoclínica e a fase romboédrica, região ainda não bem definida e sob intensa investigação. Estudos estão centrados na freqüência e na meia largura dos modos stretching nos octaedros (BO6) da estrutura perovskita (ABO3) em função da temperatura. Anomalias encontradas para amostras com 47 e 46 mol % de PbTiO3 sugerem as transições da fase monoclínica de baixa para alta temperatura ( LT M F ? HT M F ), da fase monoclínica de alta temperatura para a coexistência da fase monoclínica com a fase tetragonal ( M F ? M F + T F ), e da coexistência da fase monoclínica com a tetragonal para a fase cúbica ( M F + T F ? C F ). Na amostra com 45 mol % de PbTiO3 foram encontradas anomalias que podem também estar associadas às transições de fases, mas que não foram possíveis de serem identificadas nas fases envolvidas. / Abstract: The present work studies, through investigations of the spectra in infrared (FTIR), the transitions of structural phases of the ferroelectric system lead zirconate titanate, PbZr1- xTixO3 (PZT), in the Morphotropic Phase Boundary (MPB), region where the electrical properties of this material are at its maxiumun. We analyzed the solid solutions PbZr0,53Ti0,47O3 and PbZr0,54Ti0,46O3, which at room temperature are found within the MPB and also the composition PbZr0,55Ti0,45O3, that is located on the limit of the MPB - between the monoclinic and the rhombohedral phases - a not-yet defined region under intense investigation. Studies are concentrating on frequency and half width of the stretching modes in octahedrons (BO6) of the perovskite structure (ABO3) regarding temperature. Anomalies found in samples with 47 and 46 mol % of PbTiO3 suggest transitions in the monoclinic phase from low to high temperature ( LT M F ? HT M F ), from monoclinic phase of high temperature to the coexistence between the monoclinic phase with the tetragonal phase ( M F ? M F + T F ), and the coexistence between the monoclinic phase with tetragonal for the cubic phase ( M F + T F ? C F ). In the sample with 45 % mol of PbTiO3 we have found anomalies that can also be associated with phase transitions. Such transitions have not been possible to identify during the stages of this work. / Mestre

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