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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.
261

Association rule mining for query expansion in textual information retrieval

Zuo, Jin January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
262

Feasibility of business expansion in the seed industry

Lukach, Sarah Elizabeth January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / The landscape of the United States seed industry has changed substantially over the last 100 years. In the mid-1930s, there were 115 active seed corn companies marketing seed in the United States. By the 1980s, there were 303 hybrid seed corn companies and in 2016 there were 140 active hybrid seed corn companies in the United States. As the seed industry continues to evolve, so will the logistics and methods of which seed is sold to farm customers. The purpose of this thesis is to analyze and determine if a seed business expansion provides a positive net present value and rate of return for the management based on the capital costs of the investment and estimated income opportunities. Based on historical information of the existing business and the new market territory opportunities, a ten year projected cash flow was estimated to provide a basis for the net present value and internal rate of return analysis. Sensitivity analysis was applied to different variables in the cash flow model to identify variables of risk and the impact on the projected cash flow and net present value analysis. The projected cash flow model and net present value analysis provides management a basis for the decision to expand their existing business. The conclusion of the net present value and internal rate of return analysis was that the expansion of the seed business was profitable under most sensitivity scenarios. Recommendations were made for additional research that could be performed to maximize and diversify the business’s product offerings and net income.
263

Meze pro existenci lichých a jednoznačných expanderů / Bounds on existence of odd and unique expanders

Hlásek, Filip January 2016 (has links)
We study the existence of expander graphs with a focus on odd and unique expanders. The main goal is to describe configurations of arguments for which there is no infinite family of expanders. The most imporant result is that for every graph there is a nonempty subset of at most half of its vertices, such that every other vertex is connected at least twice to the subset or not connected to the subset at all. It follows that certain classes of unique expanders cannot exist. On the other hand we present some configurations for which there are families of expanders. Powered by TCPDF (www.tcpdf.org)
264

Resilient Power Grid Expansion with Renewable Energy Integration and Storage System

Alsuhaim, Bader Mansour, Alsuhaim, Bader Mansour January 2016 (has links)
A resilient power grid system is important to ensure the delivery of power to consumers while minimizing the cost of new technologies. Due to the increase of electricity consumption and CO2 emission, renewable energies and energy storage system are a compelling alternative. We started to identify decisions that need to be made, and parameters associated to model a power grid system expansion plan. Then, we investigated a utility company demand for the next 15 years. Also, we identified their current resources, and used that as a starting point. Then, we formulated an optimization model for a power grid expansion with different types of renewable energies, such as solar and wind, to meet the demand and minimize the cost of installation; as well as, a battery storage system (Lithium-ion) that is considered to come up with an optimal solution of a resilient power grid. Moreover, uncertainties of renewables are considered in the model, and robust optimization formulation is used to model them. Existing coal facilities are considered as a part of the model as well, and this part is designed on the optimization model in a way that would help decrease the use of such facilities and still manage them to meet demand. Numerical experiments are performed on several scenarios, and compared to what the utility company has forecasted in terms of cost, and renewable energies integration.A resilient power grid system is important to ensure the delivery of power to consumers while minimizing the cost of new technologies. Due to the increase of electricity consumption and CO2 emission, renewable energies and energy storage system are a compelling alternative. We started to identify decisions that need to be made, and parameters associated to model a power grid system expansion plan. Then, we investigated a utility company demand for the next 15 years. Also, we identified their current resources, and used that as a starting point. Then, we formulated an optimization model for a power grid expansion with different types of renewable energies, such as solar and wind, to meet the demand and minimize the cost of installation; as well as, a battery storage system (Lithium-ion) that is considered to come up with an optimal solution of a resilient power grid. Moreover, uncertainties of renewables are considered in the model, and robust optimization formulation is used to model them. Existing coal facilities are considered as a part of the model as well, and this part is designed on the optimization model in a way that would help decrease the use of such facilities and still manage them to meet demand. Numerical experiments are performed on several scenarios, and compared to what the utility company has forecasted in terms of cost, and renewable energies integration.
265

Laminin 521 maintains differentiation potential of mouse and human satellite cell-derived myoblasts during long-term culture expansion

Penton, Christopher M., Badarinarayana, Vasudeo, Prisco, Joy, Powers, Elaine, Pincus, Mark, Allen, Ronald E., August, Paul R. 13 December 2016 (has links)
Background: Large-scale expansion of myogenic progenitors is necessary to support the development of high-throughput cellular assays in vitro and to advance genetic engineering approaches necessary to develop cellular therapies for rare muscle diseases. However, optimization has not been performed in order to maintain the differentiation capacity of myogenic cells undergoing long-term cell culture. Multiple extracellular matrices have been utilized for myogenic cell studies, but it remains unclear how different matrices influence long-term myogenic activity in culture. To address this challenge, we have evaluated multiple extracellular matrices in myogenic studies over long-term expansion. Methods: We evaluated the consequence of propagating mouse and human myogenic stem cell progenitors on various extracellular matrices to determine if they could enhance long-term myogenic potential. For the first time reported, we comprehensively examine the effect of physiologically relevant laminins, laminin 211 and laminin 521, compared to traditionally utilized ECMs (e.g., laminin 111, gelatin, and Matrigel) to assess their capacity to preserve myogenic differentiation potential. Results: Laminin 521 supported increased proliferation in early phases of expansion and was the only substrate facilitating high-level fusion following eight passages in mouse myoblast cell cultures. In human myoblast cell cultures, laminin 521 supported increased proliferation during expansion and superior differentiation with myotube hypertrophy. Counterintuitively however, laminin 211, the native laminin isoform in resting skeletal muscle, resulted in low proliferation and poor differentiation in mouse and human cultures. Matrigel performed excellent in short-term mouse studies but showed high amounts of variability following long-term expansion. Conclusions: These results demonstrate laminin 521 is a superior substrate for both short-term and long-term myogenic cell culture applications compared to other commonly utilized substrates. Since Matrigel cannot be used for clinical applications, we propose that laminin 521 could possibly be employed in the future to provide myoblasts for cellular therapy directed clinical studies.
266

Stav a výhled pozice Islandu ve světové ekonomice / Iceland´s position and its future in world economy

Ramešová, Andrea January 2009 (has links)
The dissertation considers the situation of Iceland in the global economic system in context of worldwide financial crisis that affected their economy in 2008. The beginning of the thesis describes the theory of financial crises "by emphasis on the systemic model". The second part of the diploma concerns the Icelandic financial crisis and its cause and behaviour. The third section is about the effect and impact to Icelandic economy and describes stabilization measures of the government, financial help from International Monetary Fund, potential entry into the European Union and Icesave affair between Iceland, Great Britain and the Netherlands. In conclusion the Icelandic economy is compared with Irish economy during financial crisis.
267

Enriched elasto-plastic beam model / Modele de poutre elasto-platique enrichi

Corre, Grégoire 19 April 2018 (has links)
Ce travail s'inscrit dans le cadre d'un partenariat scientifique entre le Laboratoire Navier et la société STRAINS. Convaincue du besoin de renouveler les méthodes actuelles de calcul de structures, STRAINS développe un nouveau logiciel dédié à l'analyse des ouvrages d'art. Dans ce contexte, cette thèse propose de nouveaux outils pour l'analyse des structures élancées. Le modèle élastique de poutre d'ordre supérieur développé par cite{Ferradi2016} est d'abord adapté au cas des déformations imposées, permettant ainsi au modèle de représenter un grand nombre de phénomènes physiques tels que le fluage, la précontrainte ou les chargements thermiques. Différents exemples viennent souligner la précision numérique du modèle ainsi que ses performances en temps de calcul. Le modèle est également étendu au cadre de la théorie de la plasticité. Considérant les déformations plastiques comme des déformations imposées, les résultats précédemment obtenus sont utilisés pour développer une nouvelle cinématique d'ordre supérieur. Enfin, un nouvel élément de poutre élastoplastique pour le béton armé est proposé. Le béton est décrit grâce au modèle élastoplastique et les ferraillages sont modélisés par des éléments barres à une dimension. Cette méthode permet une description précise du comportement du béton et une représentation fidèle des renforcements. La validité des calculs est évaluée par des considérations de dissipation énergétique / This thesis work is presented in the framework of a scientific partnership between Laboratoire Navier and the french start-up STRAINS. Believing in the need for new methodologies in structural analysis, STRAINS is developing a new software dedicated to the structural analysis of bridges. In this context, this work suggests new tools for the analysis of slender structures.The higher-order elastic beam element developed by cite{Ferradi2016} is first extended to the case of eigenstrains, enabling the model to deal with various physical phenomena such as creep, prestress or thermal loads. An enriched kinematics is used to capture the local response of the structure. Different examples highlight the local accuracy of the model and its fast computational performances. The model is also extended to plasticity in small perturbations. Considering the plastic strains developing in the structure as eigenstrains, the previous works are used to derive a higher-order elastoplastic kinematics.Finally, a new elastoplastic beam element for reinforced concrete is suggested. The concrete material is described by using the elastoplastic beam model developed previously while steel rebars are modeled by one dimensional bar elements. This method enables a fine local description of the concrete behavior and an accurate representation of the reinforcement. The validity of computations is assessed thanks to energy considerations
268

Etude des dérégulations de l'épissage alternatif du pré-ARN messager de la troponine T cardiaque humaine associées aux dystrophies myotoniques de types 1 et 2 et des caractéristiques du facteur d'épissage MBNL1 impliqué dans ces pathologies / Study of human cardiac Troponin T pre-mRNA alternative splicing misregulation linked to myotonic dystrophies of type 1 and 2 and characteristics of the MBNL1 splicing factor involved in these pathologies

Vautrin, Audrey 18 November 2011 (has links)
Les amplifications de répétitions de triplets CTG dans le gène DMPK humain sont à l'origine de la dystrophie myotonique de type 1 ou DM1. Les répétitions CUG présentes dans les ARNm DMPK séquestrent le facteur d'épissage MBNL1 au sein de foci nucléaires et dérégulent l'épissage des pré-ARNm cibles de MBNL1. Par ailleurs, 9 isoformes de MBNL1, produites par épissage alternative, coexistent dans les cellules. Dans un premier temps nous avons recherché quels exons constitutifs ou alternatifs étaient requis pour la reconnaissance des ARN, la régulation de l'épissage et la localisation cellulaire de MBNL1. Nous avons ensuite entrepris de rechercher par l'approche SELEX les séquences de haute affinité pour MBNL1. Nous avons ainsi identifié une séquence conservée de 12 nucléotides de long, contenant un seul motif de fixation pour MBNL1 et adoptant une structuration tige-boucle particulière. L'importance de cette structuration a été confirmée par l'existence de mutants compensatoires au sein des ARN sélectionnés. Finalement nous avons étudié les mécanismes de régulation de l'inclusion de l'exon 5 du pré-ARNm de la troponine T cardiaque humaine (hcTNT). Une approche in cellulo nous a permis d'identifier les séquences minimales requises pour la régulation de l'épissage en conditions normales et en présence des répétitions CUG. Au sein de ces séquences nous avons identifié 6 nouveaux sites MBNL1 dont nous avons montré l'importance fonctionnelle in cellulo et in vitro. Nous avons également mis en évidence l'implication d'autres séquences régulatrices dans la régulation de l'inclusion de l'exon 5 du pré-ARNm hcTNT et un rôle de la protéine hnRNP H dans ces régulations. L'ensemble de ces données apportent de nouveaux éléments d'information importants pour la compréhension de la DM1 / Amplifications of CTG motifs in the human DMPK gene are responsible for Myotonic Dystrophy of type 1. The resulting CUG repeats in pre-mRNAs capture the MBNL1 splicing factor, leading to mis-regulation of MBNL1 pre-mRNA targets. Due to the recent discovery of MBNL1 and its numerous isoforms (9) resulting from alternative splicing, little is known on how MBNL1 regulates splicing and how a decreased level of available MBNL1 generates splicing miss-regulations. First, we defined which of the MBNL1 alternative and constitutive exons are required for: i) RNA binding, ii) splicing activity and, iii) MBNL1 sub-cellular localization. Second, for a more precise definition of the MBNL1 RNA binding properties, we performed SELEX experiments using a library of RNA stem-loop structures containing a 18-nt long randomized sequence. Its leads to the identification of 12-nt long sequence adopting a peculiar stem-loop structure, whose importance for MBNL1 binding was revealed by its preservation by compensatory base-pair mutations. Finally, based on the above data, we studied the mechanisms involved in regulation of hcTNT exon 5 splicing. By in cellulo assays, we defined the hcTNT pre-mRNA region required for both normal inclusion and for the trans-dominant effect of CUG repeats. Within this region, we identified six new potential MBNL1 sites and demonstrated their functional role by in vitro and in cellulo assays. We also identified several additional splicing regulatory elements involved in normal and CUG-deregulated exon 5 inclusion and already showed a role of hnRNP H in splicing regulation. Altogether, our data bring new information important for understanding the pathology
269

Asymptotics of Implied Volatility in the Gatheral Model

Tewolde, Finnan, Zhang, Jiahui January 2019 (has links)
The double-mean-reverting model by Gatheral is motivated by empirical dynamics of the variance of the stock price. No closed-form solution for European option exists in the above model. We study the behaviour of the implied volatility with respect to the logarithmic strike price and maturity near expiry and at-the-money. Using the method by Pagliarani and Pascucci, we calculate explicitly the first few terms of the asymptotic expansion of the implied volatility within a parabolic region.
270

Avaliação da influência da expansão rápida da maxila sobre a recidiva do apinhamento ântero-superior em casos tratados ortodonticamente com extrações de pré-molares / Evaluation of the influence of rapid maxillary expansion on the relapse of maxillary anterior crowding in cases ortodontically treated with premolar extraction

Martins, Patrícia Paschoal 17 January 2007 (has links)
A estabilidade a longo prazo do tratamento ortodôntico é o objetivo dos ortodontistas na busca do sucesso dos casos clínicos. Desta forma o presente estudo objetivou avaliar retrospectivamente a influência da expansão rápida da maxila na estabilidade pós-contenção do alinhamento dos dentes ântero-superiores, em casos tratados com extração de pré-molares. A amostra foi constituída de 60 pacientes de ambos os gêneros, com más oclusões de Classe I e Classe II, tratados com extrações de 4 pré-molares, utilizando-se a mecânica de Edgewise. A amostra foi dividida em dois grupos, de acordo com o protocolo de tratamento, sendo o Grupo 1 composto por 30 pacientes (14 do gênero masculino e 1 do gênero feminino), com idade inicial média de 13,55 anos (d.p.= ± 1,58 anos), tratados ortodonticamente com extrações de quatro pré-molares. O Grupo 2 apresentou 30 pacientes (9 do gênero masculino e 21 do gênero feminino), com idade inicial média de 13,98 anos (d.p.= ± 2,61 anos), tratados ortodonticamente com expansão rápida da maxila e posteriormente mecânica corretiva com extrações de quatro pré-molares ou dois pré-molares superiores. Foram avaliados os modelos de estudo referentes às fases inicial (T1), final (T2) e pós-contenção (T3) de cada paciente, medindo-se o de Little, as distâncias intercaninos, interpré-molares, intermolares, o comprimento e o perímetro do arco. A análise estatística dos dados foi realizada pela análise de variância (ANOVA) a um critério para avaliação intragrupos entre as três fases. O teste de Tukey foi aplicado nas variáveis que apresentaram resultados estatisticamente significantes. A comparação intergrupos foi realizada pelo teste t independente. O teste de Pearson foi utilizado para correlacionar o Índice de Irregularidade de Little às demais variáveis estudadas. Os resultados evidenciaram que o Índice de Irregularidade de Little apresentou 9,40% de recidiva para o grupo 1 e 13,57% para o grupo 2. Não ocorreu diferença estatisticamente significante entre os grupos na recidiva das distâncias intercaninos, interpré-molares e intermolares, no comprimento e no perímetro do arco. Entretanto, o grupo 2 apresentou maior quantidade de recidiva na quantidade de apinhamento ântero-superior em relação ao grupo 1. Portanto, houve influência da expansão rápida da maxila na estabilidade do alinhamento dos incisivos superiores. / The long-term stability of orthodontic treatment is the objective of orthodontists in the search for success in clinical cases. Thus, the present retrospective study evaluated the influence of rapid maxillary expansion on the post-retention stability of alignment of maxillary anterior teeth in patients treated with premolar extraction. The sample was composed of 60 patients of both genders, with Class I and Class II malocclusions, treated by extraction of 4 premolars and edgewise mechanics. The sample was divided into two groups according to the treatment protocol. Group 1 comprised 30 patients (14 males and 16 females), with initial mean age 13.55 years (s.d. = ± 1.58 years), orthodontically treated by extraction of four premolars. Group 2 included 30 patients (9 males and 21 females), with initial mean age 13.98 years (s.d. = ± 2.61 years), orthodontically treated by rapid maxillary expansion followed by corrective mechanics with extraction of four premolars or two maxillary premolars. Dental casts obtained from all patients at initial (T1), final (T2) and postretention stages (T3) were assessed by measurements of the Little irregularity index, intercanine, interpremolar and intermolar distances, and length and perimeter of the maxillary arch. Statistical analysis of data was performed by one-way analysis of variance (ANOVA) for evaluation within groups among the three stages. The Tukey test was applied for the variables presenting statistically significant outcomes. Comparison between groups was performed by the independent t test. The Pearson test was used to correlate the Little irregularity index to the other study variables. The results demonstrated that the Little irregularity index presented 9.40% of relapse for Group 1 and 13.57% for Group 2. There was no statistically significant difference between groups as to the relapse in intercanine, interpremolar or intermolar distance, length and perimeter of the maxillary arch. However, Group 2 exhibited greater relapse in the amount of maxillary anterior crowding compared to Group 1. Thus, rapid maxillary expansion influenced the stability of alignment of maxillary incisors.

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