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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

Modélisation et contrôle avancé pour les centrales de turbinage de moyenne et haute chute / Modeling and advanced control for medium and high head hydraulic turbines

Mesnage, Hugo 07 June 2017 (has links)
L'intégration des énergies renouvelable à l'échelle du réseau provoque de nouveaux paradigmes : la première et plus importante modification provient du fait que la puissance électrique produite n'est plus maîtrisée mais dépendante de l'incontinence des sources renouvelables. Cette irrégularité de la production par rapport à la consommation nécessite le stockage de l'énergie lorsqu'elle est produite afin de la mettre à disposition pour plus tard. Les sites de transfert d'énergie par pompage (STEP), ou centrales de turbinage-pompage, sont, par leur vitesse d'action, capacité de stockage et aspect respectueux de l'environnement, les principaux organes capable de satisfaire cette demande grandissante en stockage d'énergie à l'échelle du réseau.Durant cette thèse, le problème de modélisation et d'asservissement des régimes transitoires de ces sites est considéré du point de vue du groupe turbine : soit une turbine au sein d'un circuit hydraulique, quel est son comportement dynamique, et quelle méthode de contrôle permet d'assurer les meilleurs performances possibles du point de vue du temps de réponse et de la stabilité.Le manuscrit s'articule alors autour de quatre chapitres : le premier a pour but d'introduire plus finement les problématiques ainsi que la dynamique de ces sites. Le deuxième chapitre présente une méthode originale basée sur une étude graphique d'une modélisation simplifiée du système de turbinage au sein d'une conduite linéaire à section constante. Cette partie permet d'établir le temps minimum d'action de ces centrales de façon dépendante des performances de l'actionneur et de la topologie du site. Le troisième chapitre contient la principale contribution de ces travaux en terme de régulation d'un site de turbinage pompage : on y propose une régulation linéaire du circuit hydraulique dans lequel se fait l'écoulement de l'eau à travers l'utilisation d'un actionneur non-linéaire : la turbine. Enfin, afin de traiter des séquences particulière, le quatrième et dernier chapitre propose d'établir des trajectoires compatibles avec la dynamique et les contraintes issues de l'usage d'une turbine. Les trajectoires alors calculées permettent une plus grande maîtrise des phénomènes grâce à l'usage d'une fonction d'optimisation bien choisie et d'un retour d'état prédictif à horizon fini. / The integration of renewables at the scale of the network causes new paradigms: the first and most important change is the fact that the electrical power is no longer under control but dependent of the incontinence of renewable sources. This irregularity of production over consumption requires the storage of energy when it is produced to make it available for later. Pump storage plant (PSP) or turbine-pump equiped plants, are by their speed of action, storage capacity and environmentally respectful aspect, the main organs able to satisfy this growing demand energy storage across the network.During this thesis, the modeling problem and enslavement of transients of these sites is considered from the perspective of the turbine group: given a turbine in a hydraulic circuit, what is its dynamic behavior, and what control method ensures the best performances from the standpoint of the response time and stability.The manuscript is then structured around four chapters: the first, aims to introduce more finely issues and a mathematical representation of th dynamic of these sites. The second chapter presents an original method based on a graphic study of a simplified model of the turbine system placed along a linear and constant section penstock. This section establishes the minimum time of action of these plants dependently of the actuator performance and topology of the site. The third chapter contains the main contribution of this work in terms of regulation of a pump storage site: it proposes a linear regulation of the hydraulic circuit in which is the flow of water through the use of a non-linear actuator: the turbine. Finally, to address particular sequences, the fourth and final chapter proposes establishing trajectories compatible with the dynamics and constraints resulting from the use of a turbine. Then the computed trajectories allow greater control of the phenomena through the use of a well chosen optimization function and a predictive with finite horizon state feedback.
32

Multi-variate Process Models for Predicting Site-specific Microstructure and Properties of Inconel 706 Forgings.

Senanayake, Nishan M. January 2022 (has links)
No description available.
33

Betalsystem på webben för utvecklaren / Payment online for the developer

Elwing, Malin January 2009 (has links)
<p><p>Rapporten tar upp och behandlar ämnet betalväxlar utifrån en utvecklares perspektiv. Två företag som varit i eller nära inpå processen att utveckla en webbshop har intervjuats och jämförts med utbudet hos ett antal olika betalväxlar. Intervjuerna har visat ett resultat som är mycket troligt att man som ny utvecklare kommer i kontakt med i början. Positionen kan då vara både som utvecklare eller som ägare till webbshoppen. Det gick även att konstatera att det fanns ett antal betalväxlar lämpade för olika kunskapsnivåer. Professionell hjälp i form av råd och implementation måste inte tvunget vara en nödvändighet för att man ska kunna sätta upp en relativt avancerad webbshop.</p></p> / <p><p>This report deals with online Payment Service Providers (PSPs) from the developer's point of view. Two companies that were in or in close connection to the process of developing a web shop were interviewed and compared to the suppöy of payment options at a number of different payment PSPs. The interviews has shown a result which is probable that a new developer will get in contact with in the beginning. The position could be either as a web developer or as an owner of a web shop. It was also possible to establish that there were a number of PSPs suitable for different levels of knowledge within the field. Professional help such as advices and implementation is not necessary in order to be able to set up a relatively advanced web shop.</p></p>
34

Lysosomal network proteins as biomarkers and therapeutic targets in neurodegenerative disease

Boman, Andrea January 2015 (has links)
The pre-symptomatic stage of neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) occurs several decades before the clinical onset. Changes in the lysosomal network, i.e. the autophagosomal, endosomal and lysosomal vesicular system, are among the first alterations observed. There are currently no treatments to slow or cure neurodegenerative diseases, and there is a great need for discovery of treatment targets in cellular pathways where pathology pre-dates the neuronal death. It is also crucial to be able to diagnose neurodegenerative diseases earlier, both to enable early intervention treatment and aid in selecting clinical trial populations before the patient has widespread pathology. This thesis aims at investigating the potential of lysosomal network proteins as biomarkers and therapeutic targets in neurodegenerative disease. A targeted search for lysosomal network proteins was performed in cerebrospinal fluid (CSF) from AD patients, and seven proteins: early endosomal antigen 1 (EEA1), lysosomal-associated membrane proteins 1 and 2 (LAMP-1, LAMP-2), lysozyme, microtubule-associated protein 1 light chain 3 (LC3), Rab3 and Rab7, were elevated. The levels of EEA1, LAMP-1, LAMP-2, LC3, lysozyme and Rab3 were also measured in CSF from parkinsonian syndrome patients: PD, clinically diagnosed 4-repeat tauopathy, pathologically confirmed corticobasal degeneration (CBD) and pathologically confirmed progressive supranuclear palsy (PSP) patients. LAMP-1 and LAMP-2 were decreased in PD. LC3 and lysozyme levels were increased in 4-repeat tauopathy patients. EEA1 was decreased and lysozyme increased in PSP, and LAMP-1, LAMP-2, LC3 and lysozyme were increased in CBD. The lysosomal network proteins had different CSF protein profiles in all the parkinsonian syndromes, as well as in AD. It should be emphasized that only a select few of the lysosomal network proteins were observed to be changed, rather than a general change in lysosomal network proteins, which implicates the involvement of these seven proteins in specific pathological processes. The most interesting candidates, LAMP-2 and lysozyme, were selected for further study for their involvement in the pathology of AD. Lysozyme was found to co-localise with Aβ plaques in AD patients and overexpression prolonged survival and improved the activity in a Drosophila model of AD. Lysozyme was found to alter the aggregation pathway of Aβ1-42, to counteract the formation of toxic Aβ species and to protect from Aβ1-42 induced cell toxicity. Aβ1-42 in turn was found to increase the expression of lysozyme in both neuronal and glial cells. These data suggest that lysozyme levels rise in AD as a compensatory response which is protective against Aβ associated toxicity. LAMP-2 mRNA and protein were found increased in brain areas relevant for AD pathology and various cellular models showed complex involvement of LAMP-2 in Aβ related pathology, with extensive crosstalk between LAMP-2 and Aβ. Exposure to oligomeric Aβ1-42 caused an upregulation of LAMP-2 and in turn, overexpression of LAMP-2 caused a reduction in secreted levels of Aβ1-42, as well as changing the generation pattern of Aβ and affecting clearance and secretion of Aβ1-42. These data indicate that the increased levels of LAMP-2 in AD could be an attempt to regulate Aβ generation and secretion. In summary, this thesis reports that utilising lysosomal network proteins as biomarkers and novel therapeutic targets for neurodegenerative diseases holds great promise.
35

Ženy v současné české politice / Women in Nowadays Czech Politics

BEDNÁŘOVÁ, Kateřina January 2013 (has links)
This paper track about past and present status of woman in society and politics. We can read about history fight for women's rights in Czech and worldwide scale. After apprize of the history, we take a look at perception of gender and feminism. Then we will focus on main part of this thesis - representation of women in politics. We will do research how are woman represented at all levels of politics and do analyze of election to house of parliament in 2010. This include comparisons women at candidates to women elected into the political party. There were related campaign of political party ?Public Affairs? and we will try to figure out, if this campaing do not encourage traditional stereotypes how to perceive women in society. There were used inerview with woman contributors of this political campaing to obtain this information. There is very clear conclusion that politicians (Mgr. Karolína Peak, ThDr. Kateřina Klasnová, Ing. Lenka Andrýsová) do not see this billboard and calendar campaign as wrong move and all agree, that for unknown small politics party it was good opportunity how to make it visible.
36

Identificando dificuldades e benefícios do uso do PSP apoiado por ferramentas de 3ª. geração

Montebelo, Renan Polo 22 May 2008 (has links)
Made available in DSpace on 2016-06-02T19:05:47Z (GMT). No. of bitstreams: 1 3388.pdf: 1949798 bytes, checksum: 1a2073d52b18588ac8cb15ca66beb5d9 (MD5) Previous issue date: 2008-05-22 / Universidade Federal de Sao Carlos / Background: The Personal Software ProcessTM (PSP) is a methodology that can be used by software developers to improve the predictability, the productivity and the quality of their personal work. However, the great number of activities and metrics involved in the PSP makes its application very laborious and difficult. Several PSP supporting tools have been proposed in order to make its application more feasible, and such tools evolved as more experiments were conducted with the PSP. There are now three generations of PSP supporting tools, whereas third generation supporting tools are characterized by being able to collect and analyze Software Engineering metrics automatically and unobtrusively. Objective: This study s objective is to determine the difficulties and benefits of using third generation tools to support the PSP application. Method: The GQM paradigm was used to set up two Case Studies, one being in the academic environment with undergraduate students and another in a small software development company. Both case studies featured the PSP application supported by third generation tools. Results: Results show that third generation supporting tools have some advantages over previous generations tools, especially in the coding phase. However, third generation tools have limited PSP activities support and introduce new adoption problems. Conclusion: For a successful long-term PSP application, it is necessary that the supporting tools are completely adapted and integrated in the developers work environment, with both second and third generations tools characteristics. / Cenário: O Personal Software ProcessTM (PSP) é uma metodologia que pode ser usada por desenvolvedores de software para melhorar a previsibilidade, a produtividade e a qualidade de seu trabalho pessoal. No entanto, a grande quantidade de atividades e métricas envolvidas no PSP torna a sua aplicação bastante trabalhosa e difícil. Várias ferramentas de apoio foram propostas com o intuito de facilitar a aplicação da metodologia, sendo que tais ferramentas evoluíram à medida que estudos sobre a aplicação do PSP eram realizados. Assim, existem hoje três gerações de ferramentas de apoio ao PSP, sendo que as ferramentas de 3ª geração caracterizam-se por coletar e analisar métricas de Engenharia de Software automaticamente, sem a necessidade de intervenção direta do desenvolvedor. Objetivo: O objetivo deste trabalho é determinar as dificuldades e os benefícios do uso de ferramentas de 3ª geração para o apoio à aplicação do PSP. Método: Utilizando o paradigma GQM, foram elaborados dois estudos de caso, sendo um em ambiente acadêmico e outro em uma pequena empresa de desenvolvimento de software. Ambos os estudos de caso envolveram a aplicação do PSP com o apoio de ferramentas de 3ª geração. Resultados: Os resultados mostram que ferramentas de 3ª geração apresentam algumas vantagens em relação às ferramentas de gerações anteriores, especialmente na fase de codificação. No entanto, tais ferramentas apóiam um número limitado de atividades do PSP, além de introduzirem novos problemas de adoção. Conclusão: Para que a aplicação do PSP tenha sucesso em longo prazo é necessário que a ferramenta de apoio seja completamente adaptada e integrada ao ambiente de trabalho do desenvolvedor, apresentando tanto características de ferramentas de 2ª quanto de 3ª gerações.
37

Betalsystem på webben för utvecklaren / Payment online for the developer

Elwing, Malin January 2009 (has links)
Rapporten tar upp och behandlar ämnet betalväxlar utifrån en utvecklares perspektiv. Två företag som varit i eller nära inpå processen att utveckla en webbshop har intervjuats och jämförts med utbudet hos ett antal olika betalväxlar. Intervjuerna har visat ett resultat som är mycket troligt att man som ny utvecklare kommer i kontakt med i början. Positionen kan då vara både som utvecklare eller som ägare till webbshoppen. Det gick även att konstatera att det fanns ett antal betalväxlar lämpade för olika kunskapsnivåer. Professionell hjälp i form av råd och implementation måste inte tvunget vara en nödvändighet för att man ska kunna sätta upp en relativt avancerad webbshop. / This report deals with online Payment Service Providers (PSPs) from the developer's point of view. Two companies that were in or in close connection to the process of developing a web shop were interviewed and compared to the suppöy of payment options at a number of different payment PSPs. The interviews has shown a result which is probable that a new developer will get in contact with in the beginning. The position could be either as a web developer or as an owner of a web shop. It was also possible to establish that there were a number of PSPs suitable for different levels of knowledge within the field. Professional help such as advices and implementation is not necessary in order to be able to set up a relatively advanced web shop.
38

Semantic Segmentation of Iron Pellets as a Cloud Service

Christopher, Rosenvall January 2020 (has links)
This master’s thesis evaluates automatic data annotation and machine learning predictions of iron ore pellets using tools provided by Amazon Web Services (AWS) in the cloud. The main tool in focus is Amazon SageMaker which is capable of automatic data annotation as well as building, training and deploying machine learning models quickly. Three different models was trained using SageMakers built in semantic segmentation algorithm, PSP, FCN and DeepLabV3. The dataset used for training and evaluation contains 180 images of iron ore pellets collected from LKAB’s experimental blast furnace in Luleå, Sweden. The Amazon Web Services solution for automatic annotation was shown to be of no use when annotating microscopic images of iron ore pellets. Ilastik which is an interactive learning and segmentation toolkit showed far superiority for the task at hand. Out of the three trained networks Fully-Convolutional Network (FCN) performed best looking at inference and training times, it was the quickest network to train and performed within 1% worse than the fastest in regard to inference time. The Fully-Convolutional Network had an average accuracy of 85.8% on the dataset, where both PSP &amp; DeepLabV3 was showing similar performance. From the results in this thesis it was concluded that there are benefits of running deep neural networks as a cloud service for analysis and management ofiron ore pellets.
39

The prevalence of musculoskeletal disorders among dentists in KwaZulu- Natal

Moodley, Rajeshree January 2013 (has links)
Magister Chirurgiae Dentium (MChD) / Occupational hazards are common among many professions and dentistry is no exception. Occupational hazards include percutaneous injuries, inhalation of noxious chemicals, noise and musculoskeletal disorders (MSD). Despite the fact that MSD have been documented to be very prevalent among dentists in various countries, there is a paucity of literature from South Africa. Aim The aim of the present study was to determine the prevalence of musculoskeletal disorders among the dentists in KwaZulu-Natal (KZN), South Africa and to identify risk factors associated with it. The study was a cross-sectional, descriptive one and questionnaires were used to elicit information regarding socio-demographic details, medical history, work history and work-related posture information from dentists based in KwaZulu-Natal. A convenience sample of all qualified dentists in this region who were registered members of the South African Dental Association (SADA) was used. Results One hundred and nine dentists responded to the questionnaire. The response rate was 31%. The majority were male; a third aged between 30 - 39 years and the ratio of females to males was 1:3. Almost all the dentists reported pain in the neck, lower back and shoulder. Less than a quarter of the dentists in KZN reported hand pain, numbness in the hands and a tingling sensation in the hands. More than three quarters reported that they had no negative effects when performing restorative work and scaling and polishing, but 3.1% reported having extreme levels of pain. The most common working position reported was the 2 0' clock position. Nearly three quarters rotated their necks while performing clinical dentistry and a third tilted their shoulders towards their dominant hand. There was no relationship between Body Mass Index (BMI) and whether respondents treated patients while seated or standing and neither was there a relationship between pain in the lower back and BMI. There was a strong association between pain in the neck while performing clinical work and the number of years in practice confounded by age. When compared to other countries the prevalence of MSD is very high. The highest occurrence was for neck, back and shoulder pain. Avoiding these injuries is critical and self-recognition is important in either preventing further injuries or in increasing severity of the condition. The findings of this study suggests that it may be valuable to include ergonomic work practice in the training of dentists and dentists should be involved in a proper exercise routine which should include stretching and weight training to prevent injuries. Regular breaks should be taken to perform stretching exercises in-between the management of patients in order to reduce the risk of MSD.
40

Nitrogen nutrition of Alexandrium tamarense : using δ¹⁵N to track nitrogen source used for growth

Smith, Christa Belle 03 September 2009 (has links)
Alexandrium tamarense is a harmful algal species that can produce saxitoxins, a suite of powerful neurotoxins that bioaccumulate up the food chain and can have severe economic and health impacts. With harmful algal blooms increasing temporally and spatially, it is important for us to understand the relationship between harmful algal blooms and nutrients, particularly nitrogen from anthropogenic sources. To this end, the stable nitrogen isotopic composition (δ¹⁵N) of medium nitrate, algal cells and toxin in both nitrogen-replete and nitrogen-limited batch cultures of A. tamarense were measured in order to assess the potential for using the δ¹⁵N of the toxin as a tracer of the nitrogen source used for growth. A. tamarense cells grown under nitrate-replete conditions were depleted by 1.5‰ relative to the growth medium, and saxitoxin was depleted by 1.5‰ relative to the whole cells. Under nitrate-limiting conditions, the isotopic difference between cells and saxitoxin changed as nitrate in the growth medium was depleted, indicating uncoupling of toxin synthesis and cell growth rates under changing external nutrient conditions. Determination of the absolute magnitude of the isotopic differences between the medium nitrate and either the cells or the saxitoxin was confounded by 1) using two different nitrate sources – one nitrate source was used to grow the inoculum and a different nitrate source was used for the experimental medium - with different ‰ values and 2) the presence of an unidentified, isotopically-light, nitrogen blank in the low-nitrate medium samples. I conclude that STX nitrogen isotope values have the potential to be used as nitrogen source indicators. However, overall fractionation between whole cells and STX is unknown due to the uncoupling between cell growth and STX synthesis observed during my nitrogen-limited experiment. Based on previous research on cell growth and toxin production dynamics under different nutrient regimes, it is also reasonable to assume that the observed results here may differ if a different nitrogen source was utilized by the cells for STX production. Further research could include isotope analysis of cultures grown on different nitrogen sources, such as ammonium and urea; isotopic analysis of additional compounds, such as amino acids; or use of additional stable isotopes, such as C or O. / text

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