Dissertations / Theses: 'Moduli TEG'

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Turchi, Andrea. "Progettazione e sperimentazione di un sistema di cogenerazione statica di energia elettrica tramite celle ad effetto Seebeck." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10263/.

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Il tema della presente tesi è lo studio di progettazione e sperimentazione di un generatore termoelettrico, privo di parti in movimento, sfruttando il fenomeno dell’effetto Seebeck. La prima parte offre una panoramica introduttiva riguardo i moduli TEG e i loro possibili campi di applicazione. La seconda parte riassume le equazioni fisiche alla base del fenomeno e lo stato dell’arte della generazione termoelettrica, focalizzando l’attenzione sulle caldaie a biomassa. Nella terza parte è analizzato il procedimento progettuale dell’impianto. Partendo da un analisi comparativa di soluzioni esistenti e dall’obbiettivo di ottenere la massima efficienza dei moduli TEG si è arrivati alla determinazione dei vincoli dimensionali dei componenti direttamente interessati da scambi termodinamici. La quarta parte illustra la struttura del prototipo finale dedicato al laboratorio, la sua messa in servizio e il primo collaudo dell’impianto. I risultati ottenuti dai test sono il primo passo verso l’ottimizzazione del generatore termoelettrico che potrà quindi essere studio di un’interessante campagna sperimentale.

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2

Hendricks, Rahzia. "The use of in vitro assays to screen for endocrine modulation." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_5859_1259070342.

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&nbsp Aspalathus linearis (A. linearis), commonly known as Rooibos tea or Red bush tea and amellia sinensis (C. sinensis) or Black tea are beverages that are consumed throughout theworld. These teas possess antioxidant, immunomodulating and anti-cancer actions. The aim of this study was to use in vitro assays to screen Rooibos and Black tea for endocrine modulation. The immune modulating effects of Rooibos and Black tea were investigated using an in vitro whole blood culture (WBC) assay. Unstimulated WBCs treated with Rooibos tea secreted higher levels of IL-6, IL-10 and IFN&gamma than cultures treated with DMSO control. Rooibos treatment of stimulated WBCs resulted in higher IL-6, lower IL-10 and no effect on IFN&gamma secretion compared to DMSO treated stimulated WBC. Black tea treatment of stimulated WBC resulted in decreased IL-6, IL-10 and IFN&gamma secretion compared to the DMSO treated stimulated WBC. Extracts of Rooibos and Black tea were assessed for phytoestrogens using quantitative estrogen ELISAs. Both teas contain phytoestrogens. The quantitative ELISAs showed that Rooibos tea contained significantly lower estrone (E1), estradiol (E2) and estriol (E3) levels than Black tea. The effects of Rooibos and Black tea on proliferation of the estrogen dependant MCF-7 cell line was determined to further characterise the phytoestrogenic properties of the teas. Both Rooibos and Black tea extracts caused a significant inhibition of MCF-7 proliferation. This study shows that Rooibos tea and Black tea are beverages that can either stimulate or suppress the immune system. Also, both teas contain significant levels of phytoestrogens as determined by quantitative ELISAs. The current study confirms previous reports showing inhibition of growth in breast cancer cell lines by phytoestrogens. The findings extend related observations on the anti-carcinogenic potential of the two teas.

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3

Thompson, Megan Elizabeth Dove. "Fabrication and Testing of a Heat Exchanger Module for Thermoelectric Power Generation in an Automobile Exhaust System." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19233.

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Thermoelectric generators (TEGs) are currently a topic of interest in the field of energy harvesting for automobiles. In applying TEGs to the outside of the exhaust tailpipe of a vehicle, the difference in temperature between the hot exhaust gases and the automobile coolant can be used to generate a small amount of electrical power to be used in the vehicle. The amount of power is anticipated to be a few hundred watts based on the temperatures expected and the properties of the materials for the TEG. This study focuses on developing efficient heat exchanger modules for the cold side of the TEG through the analysis of experimental data. The experimental set up mimics conditions that were previously used in a computational fluid dynamics (CFD) model. This model tested several different geometries of cold side sections for the heat exchanger at standard coolant and exhaust temperatures for a typical car. The test section uses the same temperatures as the CFD model, but the geometry is a 1/5th scaled down model compared to an full-size engine and was fabricated using a metal-based rapid prototyping process. The temperatures from the CFD model are validated through thermocouple measurements, which provide the distribution of the temperatures across the TEG. All of these measurements are compared to the CFD model for trends and temperatures to ensure that the model is accurate. Two cold side geometries, a baseline geometry and an impingement geometry, are compared to determine which will produce the greater temperature gradient across the TEG. Master of Science

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Wanjau, Caroline. "Influence of a bleaching agent on stained direct composite resins." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7590_1260255840.

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Offenbacher, Carolina, and Ellen Thornström. "Ionospheric Models for GNSS Measurements." Thesis, KTH, Fastigheter och byggande, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277711.

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There is an increasing demand for higher precision when using Global Navigation Satellite Systems, GNSS, for positioning. The measurement uncertainty depends on multiple factors and one of them is the ionosphere. Due to the ionosphere being ionized and contains free electrons, satellite signals that propagates the ionosphere will be affected by the total electron content, TEC. There is no way to reduce the errors caused by the ionosphere for single frequency measuring, but it can be done for dual frequencies. The objective for this study was to compare different websites modeling results for disturbance on ground and ionospheric turbulence. Three websites were used in the comparison: Swedish SWEPOS, Norwegian seSolstorm and German IMPC. Due to different content on the websites, SWEPOS was compared with seSolstorm and IMPC was compared to seSolstorm on five different dates. In total 10 comparisons were made. The websites were evaluated on four criteria, designed from the point of view of a land surveyor: user friendliness, graphical representation, knowledge requirement and mobile website adaptation. Each criterion was graded on a scale from 1–5, where 5 was considered the best. The study showed that the modeling results from the websites differed and that the difference can not only be explained by different graphical representation or scales for measure. The results for the evaluation and grading of the websites where as follows: SWEPOS 16, seSolstorm 13 and IMPC 12. This makes SWEPOS the best suited website to use for a land surveyor. Vid positionsbestämning finns det ett behov av högre precision vid användandet av Global Navigation Satellite Systems, GNSS. Mätosäkerheten beror av ett flertal faktorer och en av dem är jonosfären. Tack vare att jonosfären är joniserad och innehåller fria elektroner kommer satellitsignaler som färdas genom jonosfären att påverkas av det totala elektroninnehållet, TEC. Det finns idag inget sätt för enkel frekvensmätning att eliminera den mätosäkerhet som uppstår till följd av jonosfäriska störningar, däremot är det möjligt att modellera för dessa störningar då två frekvenser används. Målet för denna studie var att jämföra olika webbplatsers modelleringsresultat för störningar på marknivå och för jonosfärisk turbulens. Tre webbplatser användes i jämförelsen: svenska SWEPOS, norska seSolstorm och tyska IMPC. På grund av att hemsidorna hade olika innehåll gällande modelleringar jämfördes SWEPOS med seSolstorm, medan IMPC jämfördes med seSolstorm. Totalt gjordes 10 jämförelser för fem olika datum. Webbplatserna utvärderades utifrån fyra kriterier vilka var utformade utifrån en mätteknikers synvinkel: användarvänlighet, grafisk representation, kunskapsbehov och mobil webbplatsanpassning. Varje kriterium betygsattes på en skala från 1–5, där 5 ansågs vara det bästa. Studien visade att modelleringsresultaten från webbplatserna skilde sig åt och att skillnaden inte kunde förklaras med olika grafiska framställningar eller skalstorlek. Resultaten för utvärdering och betygsättning av webbplatserna var följande: SWEPOS 16, seSolstorm 13 och IMPC 12. Detta gjorde SWEPOS till den bäst lämpade webbplatsen att använda för en mättekniker.

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JOE, MIJEOM. "Stage-Structured Tag-Return and Capture-Recapture Models." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010412-160147.

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Ecologists and conservation biologists have had an increasing interest in landscapeecology, fragmentation and meta-population structures and dynamics for endangered or threatened species of wildlife (Nichols et al. 1992).They have realized the need for parameter estimates to use in the multi-state models;and have tried estimation of transitionprobabilities among stages using tag-return and capture-recapture models. Thesetransition probabilities are composed of survival and movement rates andcan only be estimated separately when an additional assumption is made(Brownie et al. 1993) that movement occurs at the end of theinterval between time + 1.We generalize this workto allow different movement patterns in the intervalfor multiple tag-recovery and capture-recapture experiments. With methods of separating survival and movement rates in multi-state tag-return and capture-recapture models,we develop multi-state fishery tag return models with potential forfisheries that have multiple sites or patches with movement possible between sites. We build on models developed by Brownie et al. (1985), Pollock et al. (1991, 1995), Hoenig et al. (1998 a, b), and Hearn et al. (1998) on twice-a-year tagging for single state models.These methods allow the estimation of patch-specific natural and fishingmortality rates and movement rates between patches. We then develop multi-state fishery tag-return and capture-recapture models with potential forfisheries that have multiple sites or patches withmovement possible between sites when taggingtakes place twice a year.These methods allow the estimation of patch-specific reporting, natural and fishing mortality rates, and movement rates between patcheswith movement time following a uniform distribution for two special cases: (1) a two-site tag-return fisheries model;(2) a two-site model with capture-recapture catch and releasesampling in a marine reserve closed to regular fishing and the more usual tag-return sampling in the fishery area, since marine reserves which provide a refuge from fishing are gaining in popularity as a tool of fisheries management, but their effectiveness needs to beevaluated. We present small simulation studies andcompare the Relative Bias and Relative Standard Errors (RES) of estimatesas well as the correlations between estimates.

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Coogle, John J. "Applying Hierarchical Tag-Topic Models to Stack Overflow." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5713.

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Stack Overflow is a question and answer site for programming questions. It has become one of the most widely used resources for programmers, with many programmers accessing the site multiple times per day. A threat to the continued success of Stack Overflow is the ability to efficiently search the site. Existing research suggests that the inability to find certain questions results inunanswered questions, long delays in answering questions, or questions which are unable to be found by future visitors to the site. Further research suggests that questions with poor tag quality are particularly vulnerable to these issues.In this thesis, two approaches are considered for improving tag quality and search efficiency: automatic tag recommendations for question authors, and organizing the existing set of tags in a hierarchy from general to specific for Stack Overflow readers. A hierarchical organization is proposed for it's ability to assist exploratory searches of the site.L2H, a hierarchical tag topic model, is a particularly interesting solution to these approaches because it can address both approaches with the same model. L2H is evaluated in detail on several proposed evaluation criteria to gauge it's fitness for addressing these search challenges on Stack Overflow.

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Opuwari, Chinyerum Sylvia. "Effect of tea and herbal infusions on mammalian reproduction and fertility." Thesis, University of the Western Cape, 2013. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9358_1380809535.

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Camellia sinensis (tea) and Aspalathus linearis (rooibos) may improve reproductive function owing to their antioxidant properties. To test this hypothesis, male and female rats were given 2% and 5% green tea (Gt), black tea (Bt), unfermented rooibos (Ur) or fermented rooibos (Fr) as sole source of drinking for 52 and 21 days respectively. Control rats received tap water. In addition, TM3 Leydig cells were exposed to 0.025, 0.05, 0.1 and 0.5 % aqueous extracts of green tea, black tea, unfermented and fermented rooibos for 24h. In vitro analysis of tea and the herbal infusion revealed the phenolic property and antioxidant capacity (FRAP) in the order Gt &gt Bt &gt Ur &gt Fr. Camellia sinensis and Aspalathus linearis revealed no significant effect on serum antioxidant capacity (p &gt 0.05) and lipid peroxidation (MDA) in the kidney or liver in both male and female rats and in the testes of the male rats (p &gt 0.05). In addition, the antioxidant levels were maintained in the testes, liver and kidneys in both the male and female rats. In the male rats, no significant alterations were observed in body weight gain, liver and reproductive organs weight, and serum testosterone (p &gt 0.05). Only, 5% green tea significantly increased testosterone level (p &lt 0.05). Seminiferous tubules displayed complete spermatogenesis with abundant sperm in the lumen in all treated groups. However, a significant decrease in diameter and germinal epithelial height of these tubules were observed (p &lt 0.05). In the epididymides, epithelial height of caput region showed a significant increase (p &lt 0.01), while the cauda region was increased by Camellia sinensis but decreased by Aspalathus linearis. Sperm concentration improved significantly by green tea and unfermented rooibos (p &lt 0.05), while black tea and fermented rooibos produced a non significant effect (p &gt 0.05). Sperm viability was enhanced in all treatment groups (p &lt 0.05). Furthermore, green tea, black tea and unfermented rooibos significantly improved the motility of rat sperm (p &lt 0.05) fermented rooibos tended to improve it (p &gt 0.05). In addition, green tea, black tea and fermented rooibos enhanced acrosome reaction (p &lt 0.05). Creatinine activity was significantly higher in rats treated with black tea, unfermented rooibos or fermented rooibos (p &lt 0.05), green tea tended to increase it (p &gt 0.05) reflecting the significant increased kidney weight in the treatment groups at high concentrations. Liver markers, ALT and AST, decreased significantly in all treated groups (p &lt 0.05), except in 5% fermented rooibos where a significant increase in AST level was observed (p &lt 0.01). In the female rats, the body weight gain, and reproductive organs weight was no affected (p &gt 0.05). However, 5% fermented rooibos reduced the ovarian weight (p &lt 0.05), while 5% unfermented rooibos significantly increased the uterine weight (p &lt 0.05). Liver weight increased significantly by black tea and unfermented rooibos (p &lt 0.05) while the kidney weight increased significantly by 5% black tea (p &lt 0.05). No significant effect was observed in the level of FSH produced, on the other hand, Camellia sinensis significantly lowered the level of LH (p &lt 0.05), while Aspalathus linearis had no effect (p &gt 0.05). Creatinine activity was enhanced significantly only by 5% fermented rooibos (p &lt 0.05). Liver markers, ALT and AST were reduced in most treated groups except in fermented rooibos where an increase was observed. In addition, histological sections revealed no obvious alteration in the ovaries, uteri, kidneys and liver of all treated female rats. Camellia sinensis and Aspalathus linearis significantly reduced the level of testosterone produced in TM3 Leydig cells under stimulated conditions in vitro (p&lt 0.05). Furthermore, both plants maintained the viability and morphology of the cells. However, at 0.5% of either plant extracts, a significant decrease in the viability (p &lt 0.05) and altered morphology of the TM3 Leydig cells was observed. In conclusion, Camellia sinensis and Aspalathus linearis significantly improved certain sperm function which might be attributed to their high level of antioxidant activity. However, the prolonged exposure of both plant extracts might result in subtle structural changes in the male reproductive system and impair kidney function. In addition, fermented rooibos at high concentration may also impair the functions of the liver. In vitro, both plants were shown to possess anti-androgenic property on TM3 Leydig cells. Furthermore, both Camellia sinensis and Aspalathus linearis may be classified as weak phytoestrogens due to the changes in the weight of the uterus and ovaries observed.

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Schrinner, Martin. "Mean-field view on geodynamo models." Doctoral thesis, [S.l.] : [s.n.], 2005. http://webdoc.sub.gwdg.de/diss/2005/schrinner.

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Pillay, Sarosha. "Exploring the sensory compatibility of ten children with autism and their mothers." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1658_1272845563.

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Children with autism typically present with sensory processing difficulties that affect their ability to relate to people. This qualitative study focused on exploring the sensory processing of children with autism and their mothers, using a frame of reference of sensory integration theory. The purpose of the study was to help mothers gain knowledge and understanding into their own sensory processing so that they could develop a better understanding of their child&rsquo s sensory processing in order to facilitate better mother-child relationships. An evaluation tool, the Sensory Profiles by Dunn (1999) and the Adolescent/Adult Sensory Profile by Brown &amp Dunn (2002) was used as the instrument for gathering information on sensory processing. The population consisted of ten sets of mothers and their children with autism who attend Vera School for Learners with Autism. The Sensory&nbsp rofiles was completed to investigate the phenomenological issues regarding the sensory modulation aspects of the parent-child relationship. Each mother received individual feedback on their own and their child&rsquo s sensory processing. Two focus groups were then conducted with the mothers to determine the value of the information gained from the&nbsp rofiles. Data consisted of two audio taped feedback from the focus group. Data was analysed for emerging themes. The three major themes that emerged were, (a) You realize&nbsp ow similar you are to your child, (b) I also have needs (c) They walk away and leave you with this wreck of a child. The findings of the study suggest that an understanding of&nbsp ensory processing can influence the mother-child relationship positively.

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Krachey, Matthew James. "Hierarchical Bayesian application to instantaneous rates tag-return models." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-08182009-100250/.

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Natural mortality has always been a challenging quantity to estimate in harvested populations. The most common approaches to estimation include a regression model based on life history parameters and more recently tag-return models. In recent years, Bayesian methods have been increasingly implemented in ecological models due to their ability to handle increased model complexity and auxiliary datasets. In this dissertation, I explore the implementation of Bayesian methods to analyze tag-return data focusing on natural mortality. Chapter 1 is focused on the addition of two components to the tag-return model framework: random effects and auxiliary data. Auxiliary information on the instantaneous rate of natural mortality is provided through Hoenig's equation relating lifespan to natural mortality, and also implemented through a hierarchical prior. A simulation study validates the performance of the model while an analysis of the classic Cayuga Lake trout dataset demonstrates its use. Chapter 2 adds a change-point allowing for the estimation of two levels of natural mortality and the timing of the discrete-time shift in mortality. Analysis is focused on a Chesapeake Bay striped bass tagging dataset of fish tagged at six years of age and older from 1991-2002. Results show the ability to account for shift in timing. Contrasting with Jiang et al.'s study on the same striped bass dataset, the timing of the change-point was different between the two studies, likely because the Jiang study assumed a fixed tag-reporting probability of 0.43 whereas estimates seem to indicate it may be closer to 0.3. Chapter 3 introduces a change-point allowing for a shift in the tag-reporting probability while assuming a constant natural mortality rate. High reward tags are included in a subset of the data time-series to improve estimation. A factorial simulation design was used to investigate the model performance with different reporting rate and high reward tag scenarios. In general, the model performed very well with little bias except in the case of no high-reward tags. The model performed surprisingly well in a six year study. The results suggest the importance of high reporting rates and/ or auxiliary data sources such as high reward tags.

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Bergeron, Alison. "Characterization of the Tet-On Grb 7 and Tet-On 14-3-3 sigma mouse models." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97101.

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ErbB2 is overexpressed and amplified in about 30% of all breast tumors and is correlated with poor patient prognosis. ErbB2 knock in mouse models mimic the amplification in chromosome 11 (human chromosome 17q21-25) comprising of ErbB2 and Grb7 and a deletion in chromosome 4 (human chromosome 1p35-36) including 14-3-3σ seen in human breast cancers. Grb7 is an adaptor protein known to regulate cell migration and transcription by interacting with a cell migration protein FAK and a transcription factor protein FHL2. Grb7 overexpression has been linked to an increase in metastasis and poor patient outcome. 14-3-3σ is negative cell cycle protein that is upregulated by p53. Interestingly, 14-3-3σ has a role in down regulating ErbB2 expression by sequestering EGR2 from the nucleus to the cytoplasm. These results suggest that 14-3-3σ deletion and Grb7 overexpression in ErbB2 tumors represents an interesting target to study as its deletion may be a targeted event in the development of ErbB2 tumors.To elucidate the role of Grb7 and 14-3-3σ I generated a mouse model utilizing the Tet-On mouse model system whereby these two proteins are overexpressed in the mouse mammary epithelium. Through this study we confirmed successful localized overexpression of both Grb7 and 14-3-3σ in the mouse mammary gland epithelium. Further, we were able to confirm that individual expression of both Grb7 and 14-3-3σ lead to a ductal outgrowth defect during mammary gland development. These observations confirm that Grb7 and 14-3-3σ both play a role in mouse mammary gland development. ErbB2 est au-dessus d'exprimer et d'amplifier dans environ 30% de toutes les tumeurs de sein et est corrélé avec le pronostic patient pauvre. Le coup en ErbB2 dans des modèles de souris imitent l'amplification en chromosome 11 (chromosome humain 17q21-25) comportant d'ErbB2 et de Grb7 et une suppression en chromosome 4 (chromosome humain 1p35-36) comprenant le  14-3-3σ vu dans les cancers du sein humains. Grb7 est une protéine d'adapteur connue pour régler la migration et la transcription de cellules par l'interaction avec une protéine FAK de migration de cellules et une protéine FHL2 de facteur de transcription. Grb7 au-dessus d'expression a été lié à une augmentation de métastase et de résultats patients pauvres. Le  14-3-3σ est une protéine négative de cycle de cellules qui upregulated par p53. Intéressant, 14-3-3σ a un rôle en réglant vers le bas l'expression ErbB2 en séquestrant EGR2 du noyau au cytoplasme. Ces résultats suggèrent que la suppression 14-3-3σ et le Grb7 au-dessus de l'expression dans les tumeurs ErbB2 représente une cible intéressante pour étudier pendant que sa suppression peut être un événement visé dans le développement des tumeurs ErbB2. Ces résultats suggèrent que la suppression 14-3-3σ et le Grb7 au-dessus de l'expression dans les tumeurs ErbB2 représente une cible intéressante pour étudier pendant que sa suppression peut être un événement visé dans le développement des tumeurs ErbB2. Pour élucider le rôle de Grb7 et de 14-3-3 j'ai produit d'une utilisation de modèle de souris Tet-Sur le système modèle de souris par lequel ces deux protéines soient plus de exprimées dans l'épithélium mammaire de souris. Par cette étude nous avons confirmé réussi localisé au-dessus de l'expression de Grb7 et de 14-3-3σ dans l'épithélium de glande mammaire de souris. De plus, nous pouvions confirmer que l'expression individuelle des deux Grb7 et le  14-3-3 mènent à un défaut ductal de conséquence pendant le développement de glande mammaire. Ces observations confirment que Grb7 et 14-3-3σ les deux jeu un rôle dans le développement de glande mammaire de souris.

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Berks, Richard. "In vitro models of TEL/AML1-positive acute lymphoblastic leukaemia." Thesis, University of York, 2012. http://etheses.whiterose.ac.uk/3160/.

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Acute lymphoblastic leukaemia (ALL) is the most common cancer in children, and is characterised by the proliferation of immature lymphoid cells in the bone marrow. The fusion gene TEL/AML1, generated by the chromosome translocation t(12;21), is the most common single genetic aberration in B-lineage ALL, and is formed from the transcription factors TEL and AML1 (coded for by the genes ETV6 and RUNX1, respectively). However, it is still not clear how the presence of TEL/AML1 causes the development of leukaemia. In addition, the importance of a common secondary mutation in TEL/AML1+ leukaemia, the loss of the untranslocated ETV6 allele, is still subject to debate. The role of TEL/AML1 in malignant haematopoiesis has been previously studied in a variety of models, include in vivo mouse models, in vitro TEL/AML1+ cell lines, and ex vivo patient samples. Each of these models has contributed great amounts to our knowledge about TEL/AML1+ leukaemia; however, each type of model has its disadvantages. Here, a new model is presented which aims to complement these other models, based upon human embryonic stem cells (hESCs) expressing a TEL/AML1 transgene. These transgenic hESCs were shown to be capable of multipotent haematopoietic development, including towards B lymphocytes. The consequence of the loss of TEL in TEL/AML1+ leukaemia is not fully known. Here I provide two insights into this frequent secondary mutation. Firstly, a gene expression microarray revealed the transcriptional role of TEL and illuminated how its loss might contribute to progression of TEL/AML1+ leukaemia. Secondly, the functional role of TEL in proliferation and apoptosis was further investigated, which provided further insight about the clonal evolution of TEL/AML1+ leukaemia. In addition, new discoveries were made of potential partners for heterodimeric transcription factor complexes and targets for TEL repression, which provide new avenues for future studies. Taken together, the data presented in this thesis provides the basis for renewed study into TEL/AML1+ leukaemia which could address remaining questions about the disease.

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14

Dolo, Gilbert. "Difficulties encountered by the grade ten township learners with respect to the concept of electricity." Thesis, University of Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_2597_1398428972.

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The purpose of this study was to investigate the difficulties encountered by the grade ten township learners with respect to the concept of electricity. More specifically, the study attempted to explore the learners&rsquo scientific knowledge by investigating their conceptions or alternative conceptions about electricity the influence of learners&rsquo age, career interests and gender issues on their conceptions of electricity and the effectiveness of concept mapping (a pedagogic tool designed by Novak in the 1970s) in facilitating the learners&rsquo understanding of electricity. The study was premised on socio-cultural constructivism as well as meaningful learning as espoused by Ausubel (1968). A Pre-Test-Post-Test Control Group Design was adopted in the study in which two comparable groups were used. The data was analyzed using both qualitative and quantitative research methods and the instruments that were used included a conception of electricity (COET) (originally adopted and administered in the Western Cape, Northern Cape provinces and in Norway in 1999 for the purpose of Science and Technology Literacy Project (STLP) with the hope that their reliability and validity was guaranteed) selected learner interviews and evaluation forms. The summary of findings has suggested that the Grade ten learners held misconceptions about the concept of electricity even after they were exposed to intervention that included concept mapping. In terms of the gender issues, there was no significant difference in performance between the boys and girls though the females outperformed their male counterparts at both groups. The underachievement of the older learners compared to the younger ones has also surfaced and that is against expectation since a number of studies carried out earlier (see Ogunniyi (1999)) have already corroborated such findings. With respect to career interests, what the learners indicated as their future dreams, i.e. what they intend to do and become, seems to have been influenced their performance at the pre- and post-test stages.

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15

Mejia, Fernandez Cristhian Jesús. "“Modelo para el reconocimiento de patrones en formularios”." Universidad Mayor de San Andrés. Programa Cybertesis BOLIVIA, 2008. http://www.cybertesis.umsa.bo:8080/umsa/2008/mejia_fc/html/index-frames.html.

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La presente Tesis de Grado “Modelo Para el Reconocimiento de Patrones en Formularios” surge debido a problemas académicos, principalmente durante la corrección de lo que son exámenes de opción múltiple y mas allá para la valoración de datos que se encuentran en test psicológicos y encuestas. La presente Tesis plantea resolver dichos problemas con la construcción de una herramienta que permita reconocer aquellas características que se presentan en un formulario de tipo test (exámenes, tests psicológicos, encuestas etc.), de tal forma de proporcionar a los desarrolladores de software esta herramienta para la construcción de sistemas acordes a las necesidades del usuario. Para el reconocimiento de los patrones en los diferentes tipos de formularios se estudio lo que es el procesamiento de imágenes ya que estas se obtendrán a partir de imágenes digitalizadas por un escáner, y formulas matemática para la ubicación de los patrones que se procesaran con dicha técnica. Para el desarrollo de la herramienta se utiliza la metodología de desarrollo Programación Extrema, la cual tiene un desarrollo incremental y evolutivo, permitiendo al usuario proponer cambios al software a bajo costo, a lo largo del desarrollo del proyecto, esta metodología permite el desarrollo de un software de calidad, de manera eficiente y ágil.

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Taylor, John E. "COTS software decision support models for USPACOM's Theater Engagement Plan (TEP)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA384595.

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Thesis (M.S. in Systems Engineering) Naval Postgraduate School, Sept. 2000. Thesis advisor(s): Powell, James R.; Buettner, Raymond R. "September 2000." Includes bibliographical references (p. 139-141). Also available in print.

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Cochran, Jordon T. "Ten propositions regarding cyberpower /." Maxwell AFB, Ala. : School of Advanced Air and Space Studies, 2008. https://www.afresearch.org/skins/RIMS/display.aspx?moduleid=be0e99f3-fc56-4ccb-8dfe-670c0822a153&mode=user&action=downloadpaper&objectid=69da47d8-1f38-4cdc-a382-b376ad030dba&rs=PublishedSearch.

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18

Herold, Matthias. "Tropical orbit spaces and moduli spaces of tropical curves." Phd thesis, Université de Strasbourg, 2011. http://tel.archives-ouvertes.fr/tel-00550370.

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Un principal résultat de la thèse est une preuve conceptionnelle du fait que le nombre pondéré de courbes tropicales de degré et genre donnés qui passent par le bon nombre de points en position générale dans $\RR^2$ (resp., qui passent par le bon nombre de points en position générale dans $ \RR^r $ et représentent un point fixé dans l'espace de modules de courbes tropicales abstraites de genre g ) ne dépend pas du choix de points. Un autre principal résultat est un nouveau théorème de correspondance entre les cycles tropicaux plans et les courbes algébriques elliptiques planes.

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Burel, Guillaume. "Bonnes démonstrations en déduction modulo." Phd thesis, Université Henri Poincaré - Nancy I, 2009. http://tel.archives-ouvertes.fr/tel-00372596.

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Cette thèse étudie comment l'intégration du calcul dans les démonstrations peut les simplifier. Nous nous intéressons pour cela à la déduction modulo et à la surdéduction, deux formalismes proches dans lesquels le calcul est incorporé dans les démonstrations via un système de réécriture. Pour améliorer la recherche mécanisée de démonstration, nous considérons trois critères de simplicité. L'admissibilité des coupures permet de restreindre l'espace de recherche des démonstrations, mais elle n'est pas toujours assurée en déduction modulo. Nous définissons une procédure qui complète le système de réécriture pour, au final, admettre les coupures. Au passage, nous montrons comment transformer toute théorie pour l'intégrer à la partie calculatoire des démonstrations. Nous montrons ensuite comment la déduction modulo permet de réduire arbitrairement la taille des démonstrations, en transférant des étapes de déduction dans le calcul. En particulier, nous appliquons ceci à l'arithmétique d'ordre supérieur pour démontrer que les réductions de taille qui sont possibles en augmentant l'ordre dans lequel on se place disparaissent si on travaille en déduction modulo. Suite à ce dernier résultat, nous avons recherchés quels sont les systèmes d'ordre supérieur pouvant être simulés au premier ordre, en déduction modulo. Nous nous sommes intéressés aux systèmes de type purs et nous montrons comment ils peuvent être encodés en surdéduction, ce qui offre de nouvelles perspectives concernant leur normalisation et la recherche de démonstration dans ceux-ci. Nous développons également une méthodologie qui permet d'utiliser la surdéduction pour spécifier des systèmes de déduction.

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Waterhouse, Lynn. "Partial Year Tagging Models: Accounting for Changing Tag Visibility and Delayed Mixing." W&M ScholarWorks, 2010. https://scholarworks.wm.edu/etd/1539617896.

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Dube, Admire. "The design, preparation and evaluation of Artemisia Afra and placebos in tea bag dosage form suitable for use in clinical trials." Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_2915_1188480959.

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Artemisia Afra, a popular South African traditional herbal medicine is commonly administered as a tea infusion of the leaves. However, clinical trials proving it safety and efficacy are lacking mainly due to the absence of good quality dosage forms and credible placebos for the plant. The objectives of this study were to prepare a standardized preparation of the plant leaves and freeze-dried aqueous extract powder of the leaves, in a tea bag dosage form and to design and prepare credible placebos for these plant materials.

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22

Jiang, Honghua. "Age-Dependent Tag Return Models for Estimating Fishing Mortality, Natural Mortality and Selectivity." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-09072005-085405/.

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We extend the instantaneous rates formulation of fisheries tag return models to allow for age-dependence of fishing mortality rates in Chapter 1. This is important in many applications where tagged fish vary over a large range of ages (and sizes). We focus on a model based on assuming selectivity by age is constant over years and that above a certain age selectivity is fixed at 1. We show that it is possible to allow natural mortality, M, to vary by age and year. We allow for incomplete mixing of tagged fish and for fisheries to be pulse, continuous or continuous over part of the year. We focus on the case where all or most age classes are tagged each year. We investigate model identifiability and how well parameters can be estimated using analytic and simulation methods. Results show that some models with the tag reporting rate estimated are singular or near-singular. The age-length key method commonly used for age specification may produce substantial errors in converting size to age, especially for the older fish. To reduce such errors, in Chapter 2 we propose two alternative sampling designs to the standard one of tagging all age classes: one where only age 1 fish are tagged, another where both age 1 and age 2 fish are tagged. Catch-and-release fisheries have become very important to the management of overexploited recreational fish stocks. Tag return studies where the tag is removed regardless of fish disposition have been used to assess the effectiveness of restoration efforts for these catch-and-release fisheries. In Chapter 3, we extend the instantaneous rate formulation of tag return models introduced in Chapter 1 to catch-and-release tagging studies. We illustrate the methods using multiple age class tag return data on striped bass (Morone saxatilis) from the Maryland Department of Natural Resources (MDNR). We found evidence that M is age dependent and that M has increased since 1999 possibly due to an outbreak of the disease (mycobacteriosis) in striped bass in the Chesapeake Bay.

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Wichers, Sacha. "Verification of numerical models for hydrothermal plume water through field measurements at TAG." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/39173.

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Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering; and the Woods Hole Oceanographic Institution), 2005. Includes bibliographical references (p. 63-65). Hydrothermal vents discharge superheated, mineral rich water into our oceans, thereby providing a habitat for exotic chemosynthetic biological communities. Hydrothermal fluids are convected upwards until they cool and reach density equilibrium, at which point they advect laterally with the current. The neutrally buoyant plume layer can have length scales on the order of several kilometers, and it therefore provides the best means to detect the presence of vent fields on the seafloor, which typically have length scales on the order of a few meters. This thesis uses field measurements of the velocity, temperature and particulate anomalies associated with the TAG hydrothermal plume to demonstrate that tidal currents exert a strong impact on the plume shape, and to provide new constraints on the thermal power of the TAG hydrothermal system. The results show that the power output of the TAG system is on the order of 6000 MW, which is up to two orders of magnitude greater than previous estimates, and that there is considerably more entrainment than had previously been assumed. by Sacha Wichers. S.M.

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Beyhom, Amine. "Systématique modale." Paris 4, 2003. https://hal.archives-ouvertes.fr/tel-01511710.

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L'auteur passe en revue, en première partie (sur trois), les différentes théories du maqâm ayant eu cours au XXe siècle : ces théories suivent deux pistes apparemment inconciliables - d'un côté une fixation des intervalles utilisés en musique arabe dans un système d'accordage pythagoricien, de l'autre une représentation de ces mêmes intervalles en multiples du quart de ton. L'auteur, constatant que ces intervalles sont fluctuants selon les régions, les modes, ou encore l'esthétique musicale de chaque interprète, arrive à la conclusion que cette dernière approximation constitue un compromis acceptable entre précision et pratique : la deuxième partie consiste en une théorisation de la " systématique modale " ainsi que par des études complémentaires, y compris statistiques, sur la méta-structure du mode ; deux études particulières concernent les systèmes pentatoniques et les systèmes heptatoniques en multiples de demi-ton. Quelques fondamentaux de la musique (par exemple les causes d'existence de l'heptatonisme et du pentatonisme) reçoivent un nouvel éclairage à la suite des résultats de cette deuxième partie. En troisième partie, l'auteur aborde plus particulièrement la systématique du maqâm : à l'aide des tableaux synoptiques des échelles modales de la musique arabe relevées dans la littérature et rangées et commentées selon la méthode théorique mise au point en deuxième partie, l'auteur effectue une première synthèse incorporant les genres et les échelles de la musique arabe - cette démarche permet de faire ressortir des critères spécifiques (et implicites) inhérents à la musique du maqâm, et non repérées par d'autres méthodes d'analyse : elle permet aussi d'identifier des échelles alternatives, satisfaisant à ces critères, et non-constatées dans la pratique musicale traditionnelle. La systématique modale est une théorie qui n'en est qu'à ses débuts : plusieurs applications complémentaires, dans le domaine du maqâm ou des musiques du monde, sont prévues ; les Annexes à la troisième partie comportent un tableau exhaustif des 685 échelles heptatoniques paradigmatiques (générant chacune sept aspects par décalage de la tonique) " réalistes " (dans un ambitus d'intervalles allant du demi-ton au ton et demi) et constituant un réservoir modal ainsi qu'une méthode de rangement des échelles modales favorisant des études comparatives, notamment avec la musique de l'Inde ou la musique grecque ancienne Modal systematics is a new theory of modal music based on a model inspired by maqâm theories of the 2Oth century: the author expands the quarter-tone representation of modal structure developed mainly by Erlanger (1930ies) and integrates it into a global combinatory theory which allows numerous theoretical projections. The intervals of modal music are considered to be approximate multiples of the quarter-tone interval, within a range from one semi-tone to one and a half tone. Specific studies of pentatonic and heptatonic systems are carried, and a general model of scale generation is proposed in the thesis; the model brings new explanations of some fundamentals of music, particularly concerning the constitution of pentatonic and heptatonic scales: synoptical tables of modal scales of Arabic music are included, allowing further exploration of maqâm structure; a number of intrinsic criteria of the building of the arabic scales, never described before in specialised literature (to the knowledge of the author), are discovered using the modal systematics method - this specific research uses a combined genre-scale approach allowed by the modal systematics theory. Complementary studies of the maqâm by the method emphasize the possibilities of traditional modulation and present new, alternative scales, for composers. The appendix proposes an exhaustive list of potential modal combinations of musical intervals (4795 modal scales), allowing a comparative study between different types of music. The theory of modal systematics still has many domains to explore, including specific characteristics of maqâm music and extensions to other musics of the world: it may be used in such various domains as ancient Greek music, Indian music or even music with less obvious connection to Arabic maqâm ; the model based on quarter-tone approximation can also be extended to 1/8 tone or any other integral division of the octave

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Hříbalová, Pavlína. "Testování Fed modelu." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-73882.

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Diploma Thesis focuses on Fed Model testing and its credibility on market data. The research is based on Gordon Model and Capital Asset Pricing Model (CAPM), it explains, what the basic features of the Fed Model are and describes its derivation from Gordon Model. The Thesis shows possible Fed Model limitation. It uses the US market, Great Britain and Germany 1979 -- 2011 data to demonstrate validity of the model. Eventually possible reasons of Fed Model development in period 2002 -- 2011 are presented.

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26

Li, Jinhui. "Regulation of NFkappaB-Mediated Inflammation By Green Tea in Obese Models of Nonalcoholic Steatohepatitis." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492088369370696.

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27

Borges, Antônio Carlos. "Expressão de um fragmento da Miosina Va inibe o crescimento de tumores de melanoma induzidos em modelo animal." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/17/17136/tde-10022012-135441/.

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A miosina Va é uma proteína motora envolvida no transporte e posicionamento de vesículas, organelas e mRNA. Além disso, postulou-se que a miosina-Va atua no seqüestro do fator pró-apoptótico, Bmf, no citoesqueleto de actina. Pesquisas realizadas em nosso laboratório demonstraram que um fragmento da miosina Va (MVaf), que corresponde ao sítio ligante de DLC2-Bmf, é capaz de induzir intensa apoptose em células de melanoma e de carcinoma in vitro. O presente trabalho teve por objetivo principal avaliar o potencial do MVaf como agente antitumoral, através de abordagens de terapia gênica em modelo animal. Foram geradas linhagens estabilizadas e com expressão controlada pelo sistema Tet-ON onde a expressão de EGFP ou EGFP-MVaf é induzida com a adição de doxiciclina. Essas linhagens foram testadas quanto à porcentagem de morte por apoptose e ativação de caspases. Tumores foram induzidos em camundongos C57BL/6 por inoculação subcutânea de células tumorigênicas positivas ou não para a expressão de EGFP-MVaf. Também foram utilizadas linhagens de fibroblasto embrionário murino selvagem (MEFs WT) e nocautes para os fatores Bim/Bmf e Bax/Bak (MEFsBim-/-,Bmf-/-; MEFsBax-/-,Bak-/-) para estudos do mecanismo de ação do fragmento da miosina Va. Observou-se que a adição de butirato de sódio potencializa a expressão de EGFP-MVaf e, conseqüentemente, o efeito pró-apoptótico desse fragmento e que essas células são mais sensíveis aos quimioterápicos etoposídeo e taxol, apresentando maior susceptibilidade à apoptose. Verificou-se que a expressão de EGFP-MVaf em células de tumores de melanoma induzidos em camundongos C57BL/6J dificulta o crescimento desses tumores. Quanto ao estudo com MEFs, observou-se que células nocautes para os fatores pró-apoptóticos Bim/Bmf e Bax/Bak são menos susceptíveis à morte induzida pelo fragmento da miosina Va. Indução da expressão de MVaf desencadeia a liberação da proteína proapoptótica Smac (fusionada ao repórter fluorescente Cherry) do espaço intermembranas da mitocôndria para o citoplasma sugerindo que a morte apoptótica induzida por MVaf requer a permeabilização da membrana mitocondrial externa (MOMP). Concluindo, os dados apresentados aqui nos permitem propor o MVaf como uma molécula promissora para o desenvolvimento de novas abordagens terapêuticas contra o câncer. Myosin Va is a motor protein involved in the transport and positioning of vesicles, organelles and mRNA. Additionally, myosin-Va has been implicated in the sequestering of a proapoptotic factor, Bmf, to the actin cytoskeleton. Research in our laboratory demonstrated that a fragment of myosin Va (MVaf), which corresponds to the binding site of DLC2-Bmf, is capable to induce intense apoptosis in melanoma and carcinoma cells in vitro. Here, our goal was to assess the potential of MVaf as antitumor agent, through gene therapy approaches in animal models. We generated Tet-ON controlled B16-F10 melanoma cells whose expression of EGFP or EGFP-MVaf is induced with the addition of doxycycline. These cells were tested for apoptotic death and activation of caspases, and were used to induce tumors in C57BL/6J mice by subcutaneous inoculation. We also used cell lines of murine embryonic fibroblasts, wild-type (MEFs WT) and knockouts for the proapoptotic proteins Bim/Bmf or Bax/Bak (MEFsBim-/-,Bmf-/-, MEFsBax-/-,Bak-/-), to study the mechanism by which MVaf induces apoptosis. We observed that addition of sodium butyrate to the cultures enhances the EGFP-MVaf expression and, consequently, the pro-apoptotic effect of this fragment. Treated cells were more sensitive to the chemotherapeutic drugs etoposide and taxol, showing a higher susceptibility to apoptosis. Moreover, in vivo induction of EGFP-MVaf expression retards growth of B16-F10 melanoma tumors in mouse model. As for the study with MEFs, we observed that cells knockout for the proapoptotic factors Bim/Bmf or Bax/Bak are less susceptible to death induced by MVaf than wild-type MEFs. Accordingly, we showed that MVaf expression triggers release of the proapoptotic protein Smac (tagged with the fluorescent protein Cherry) supporting the involvement of the mitochondrial outer membrane permeabilization (MOMP) in the MVaf-induced apoptotic death response. In conclusion, these data lead us to propose MVaf as a promising molecule for the development of new therapeutic approaches against cancer.

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Houtmann, Clément. "Représentation et interaction des preuves en superdéduction modulo." Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00553219.

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Cette thèse propose et étudie de nouveaux systèmes déductifs mêlant calculs et déductions. La déduction modulo est un premier formalisme qui traduit un pouvoir calculatoire grâce à un système de réécriture. Nous présentons un paradigme dual appelé superdéduction qui traduit un pouvoir déductif par de nouvelles inférences. Ces pouvoirs calculatoires et déductifs modifient la représentation des preuves et leur interaction par les processus d'élimination des coupures. La normalisation forte ou l'admissibilité des coupures ne sont plus garanties et apparaissent alors comme des propriétés intrinsèques des théories représentées sous forme de systèmes de réécriture. Nous démontrons que certains critères permeent d'assurer ces propriétés, notamment en définissant un langage de termes de preuve pour la superdéduction et en étudiant la permutabilité des inférences en calcul des séquents classique. Notre attention est focalisée sur les calculs des séquents classiques et la représentation des preuves dans de tels systèmes. D'autres formalismes connexes sont envisagés, notamment les réseaux de preuve et le focusing. Nous comparons cette dernière approe à la superdéduction, ce qui nous amène à proposer une refonte du paradigme de superdéduction basée sur un système de multifocusing pour la logique classique. Nous en montrons les effets bénéfiques en démontrant la complétude des systèmes déductifs obtenus.

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29

Rebolledo, Marusia. "Module supersingulier et points rationnels des courbes modulaires." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00008022.

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Nous étudions ici le groupe libre engendré par les classes d'isomorphisme de courbes elliptiques supersingulières en caractéristique $p$ appelé module supersingulier. Nous le comparons à d'autres modules de Hecke : l'homologie de la courbe modulaire $X_0(p)$ et l'ensemble des formes modulaires de poids $2$ et de niveau $p$. Nous donnons des interprétations et des applications des formules de Gross et Gross-Kudla concernant les fonctions L de formes modulaires. Les liens entre le module supersingulier et la géométrie de $X_0(p)$ nous permettent d'appliquer ces résultats à l'étude des points rationnels de certaines courbes modulaires. Reprenant une méthode de Momose et Parent, nous déterminons notamment un ensemble infini de nombres premiers $p$ pour lesquels le quotient de $X_0(p^r)$ ($r\geq 2$) par l'opérateur d'Atkin-Lehner n'a pour points rationnels que les pointes et les points CM.

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30

Rebolledo-Dhuin, Marusia. "Module supersingulier et points rationnels des courbes modulaires." Paris 6, 2004. https://tel.archives-ouvertes.fr/tel-00008022.

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31

Johansson, Emma. "Bilayer Discs - Fundamental Investigations and Applications of Nanosized Membrane Models." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8200.

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32

Nahon, Fabrice. "Preuve par induction dans le calcul des séquents modulo." Phd thesis, Université Henri Poincaré - Nancy I, 2007. http://tel.archives-ouvertes.fr/tel-00259803.

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Nous présentons une méthode originale de recherche de preuve par récurrence utilisant la surréduction. Elle a la particularité d'être fondée sur la déduction modulo et d'utiliser la surréduction pour sélectionner à la fois les variables de récurrence et les schémas d'instanciation. Elle donne également la possibilité de traduire directement toute dérivation effectuée avec succès en une preuve dans le calcul des séquents modulo. La correction et la complétude réfutationnelle de la méthode sont démontrées en théorie de la preuve. Nous étendons ensuite cette première approche aux théories de réécriture équationnelles constituées d'un système de réécriture R et d'un ensemble E d'égalités. A partir du moment où le système de réécriture équationnel (R,E) possède de bonnes propriétés de terminaison et de complétude suffisante, et si on suppose également que E préserve les constructeurs, la surréduction au niveau des positions les plus profondes où apparaît un symbole défini s'effectue uniquement à l'aide d'unificateurs qui sont également des substitutions constructeurs. Ceci est particulièrement intéressant dans le cas des théories associatives, ou associatives commutatives, pour lesquelles notre système de recherche de preuve a été raffiné.

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33

Teng, Long [Verfasser]. "Modelling of Credit Risk and Correlation Risk: Time-Dependent and Stochastic Correlation Models / Long Teng." Wuppertal : Universitätsbibliothek Wuppertal, 2015. http://d-nb.info/1081328908/34.

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Oliveira, Jéssica dos Santos de. "Classificador para auxílio ao diagnóstico de TEA baseado em um modelo computacional de atenção visual." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/100/100131/tde-01022018-100042/.

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O Transtorno do Espectro do Autismo (TEA) é um transtorno do neurodesenvolvimento que afeta principalmente as habilidades de interação social dos indivíduos. Para auxiliar no diagnóstico, estudos têm utilizado técnicas de rastreamento de olhar, mas, em geral, os sinais são interpretados manualmente ou a automatização considera somente alguns dos indícios que podem definir a presença do TEA em indivíduos. O presente projeto visa a preencher esta lacuna, propondo utilizar os dados do rastreamento do olhar para o desenvolvimento de um modelo de atenção visual para TEA e para Desenvolvimento Típico (DT). A partir desses modelos, é construído um classificador que visará auxiliar no diagnóstico do TEA. Para alcançar o objetivo proposto, foram realizadas as seguintes etapas: revisão bibliográfica, aprovação do comitê de ética, definição do modelo de atenção visual, implementação do modelo, análise e publicação dos resultados. Os métodos foram testados com técnica de validação cruzada e construção de curva ROC. Os resultados mostraram que o modelo de atenção visual desenvolvido é capaz de prever a atenção visual do grupo TEA e do grupo DT, e que o método para classificação desenvolvido consegue classificar um indivíduo com TEA com média de 90\\% de precisão e 83\\% de especificidade, atingindo no melhor resultado 96\\% de precisão e 93\\% de especificidade. Espera-se que o método possa ser utilizado por profissionais da área de saúde e que sirva de base também para outras aplicações Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that affects mainly social interaction skills of individuals. In order to aid the diagnosis, studies have used eye-tracking techniques, but, in general, the signals are interpreted manually or the automation considers only some of the evidence that may define the presence of the ASD in individuals considering eye-tracking signals. This project aims at contributing to this challenge, processing data provided from eye-tracking based on a visual attention model for ASD and Typical Development (TD). From this model its build a classifier that will aid ASD diagnosis. To achieve the proposed goal, the following steps were performed: literature review, approval of the ethics committee, definition of a visual attention model, model implementation, analysis and publication of results. The methods were tested with cross-validation technique and ROC curve construction. The results showed that the developed model is able to predict visual attention of the TEA group and the DT group, and that the developed training method can classify an individual with TEA with an average of 90\\% of precision and 83\\% of specificity. In the best result was achive 96\\% of accuracy and 93\\% of specificity. It is expected that the method can be used by health professionals and also serve as a basis for other applications

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35

Jaeger, Laurence. "L'evaluation du risque dans le systeme des transports routiers par le developpement du modele tag." Strasbourg 1, 1998. http://www.theses.fr/1998STR1EC03.

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La problematique de la these consiste a modeliser et a evaluer le risque dans le systeme des transports routiers en france. Le developpement du modele tag (transports routiers, accidents, gravite) permet de mesurer l'incidence des facteurs multiples et varies qui interagissent sur le risque routier. L'objectif principal du premier chapitre est d'elaborer un cadre methodologique pour la conception et la realisation d'un modele explicatif de l'insecurite routiere. Le modele tag repose sur quatre categories d'indicateurs du risque routier en france : une mesure de l'exposition au risque, une mesure du risque comportemental et technologique, la frequence des accidents et le taux de gravite. La difficulte a ce stade est de disposer d'une mesure de l'exposition au risque. Ainsi, l'absence d'un systeme de recueil d'information sur l'activite du secteur des transports routiers nous contraint a elaborer dans le second chapitre une methodologie originale. Nous evaluons, sur une base mensuelle entre 1957 et 1993, le nombre de kilometres effectues sur le reseau routier francais par l'ensemble des vehicules. L'objectif principal du troisieme chapitre consiste d'une part a representer le systeme dans sa globalite de facon a identifier les facteurs qui influent sur le bilan routier et d'autre part a reconstituer les series statistiques retranscrivant au mieux les differents phenomenes. Le quatrieme chapitre constitue donc le volet principal de ce travail de recherche. Ce chapitre presente l'ensemble des resultats obtenus par l'estimation du modele tag sur la periode de janvier 1956 a decembre 1993. Nous exposons, dans un premier temps, la formulation econometrique retenue. Nous evaluons, dans un deuxieme temps, l'impact des facteurs identifies precedemment sur l'exposition au risque et sur le risque comportemental et technologique. Nous presentons et interpretons, dans un troisieme temps, les resultats de l'estimation complete du modele tag The problems of the thesis consist in modelling and evaluating the risk in the system of the road transport in france. The development of model tag (road transport, accidents, gravity) evaluates the incidence of the multiple and varied factors which interact on the road risk. The principal objective of the first chapter is to work out a methodological framework for the conception and the realization of an explanatory model of the road insecurity. Model tag rests on four categories of indicators of the road risk in france : a measurement of the exposure to the risk, a measurement of the behavioral and technological risk, the frequency of the accidents and the rate of gravity. The difficulty is to have a measurement of the exposure to the risk. Thus, the absence of a system of information's collection on the activity of the road transport sector us constrained to work out in the second chapter an original methodology. We evaluate, on a monthly basis between 1957 and 1993, the number of kilometers carried out on the french road network by the whole of the vehicles. The objective of the third chapter consists in on the one hand representing the system as a whole in order to identify the factors which influence the road assessment and on the other hand to reconstitute the statistical series. The fourth chapter thus constitutes the principal section of this research project. This chapter presents the whole of the results obtained by the estimate of model tag over the period from january 1956 to december 1993. We expose, initially, the econometric formulation selected. We evaluate, in the second time, the impact of the factors identified previously on the exposure to the risk and on the behavioral and technological risk. We analyse, in the third time, the results of the complete estimate of model tag

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Kopaniszen, Malgorzata. "Protective effect of green tea polyphenols on dinitrobenzene sulphonicacid (DNBS)-induced colitis in mice." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40687466.

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Khodabandelou, Ghazaleh. "Mining Intentional Process Models." Phd thesis, Université Panthéon-Sorbonne - Paris I, 2014. http://tel.archives-ouvertes.fr/tel-01010756.

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Jusqu'à présent, les techniques de fouille de processus ont modélisé les processus en termes des séquences de tâches qui se produisent lors de l'exécution d'un processus. Cependant, les recherches en modélisation du processus et de guidance ont montrée que de nombreux problèmes, tels que le manque de flexibilité ou d'adaptation, sont résolus plus efficacement lorsque les intentions sont explicitement spécifiées. Cette thèse présente une nouvelle approche de fouille de processus, appelée Map Miner méthode (MMM). Cette méthode est conçue pour automatiser la construction d'un modèle de processus intentionnel à partir des traces d'activités des utilisateurs. MMM utilise les modèles de Markov cachés pour modéliser la relation entre les activités des utilisateurs et leurs stratégies (i.e., les différentes façons d'atteindre des intentions). La méthode comprend également deux algorithmes spécifiquement développés pour déterminer les intentions des utilisateurs et construire le modèle de processus intentionnel de la Carte. MMM peut construire le modèle de processus de la Carte avec différents niveaux de précision (pseudo-Carte et le modèle du processus de la carte) par rapport au formalisme du métamodèle de Map. L'ensemble de la méthode proposée a été appliqué et validé sur des ensembles de données pratiques, dans une expérience à grande échelle, sur les traces d'événements des développeurs de Eclipse UDC.

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Maicu, Maria Christina. "Optimisation of retention of mangiferin in Cyclopia subteranata during preparation for drying and storage of green honeybush and development of NIR spectroscopy calibration models for rapid quantification of mangiferin and xanthone contents /." Link to the online version, 2008. http://hdl.handle.net/10019/780.

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Couchot, Francois. "Anneaux de valuation et anneaux à type de module borné." Habilitation à diriger des recherches, Université de Caen, 2008. http://tel.archives-ouvertes.fr/tel-00881621.

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Ce mémoire est une présentation des travaux que l'auteur a réalisé en théorie des aneaux et des modules. Plus précisément l'auteur s'est consacré à l'étude des anneaux commutatifs arithmétiques et plus particulièrement aux anneaux de valuation (non nécessairement intègres). Le résultat le plus remaquable est la démonstration du théorème qui dit que tout annean local à type de module borné est un anneau de valuation presque maximal. Sont aussi présentés des résultats sur la localisation des modules injectifs et sur les enveloppes pure-injectives de certains modules.

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Braibant, Thomas. "Algèbres de Kleene, réécriture modulo AC et circuits en coq." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00683661.

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Cette thèse décrit trois travaux de formalisation en Coq. Le premier chapitre s'intéresse à l'implémentation d'une procédure de décision efficace pour les algèbres de Kleene, pour lesquelles le modèle des langages réguliers est initial : il est possible de décider la théorie équationelle des algèbres de Kleene via la construction et la comparaison d'automates finis. Le second chapitre est consacré à la définition de tactiques pour la réécriture modulo associativité et commutativité en utilisant deux composants : une procédure de décision réflexive pour l'égalité modulo AC, ainsi qu'un greffon OCaml implémentant le filtrage modulo AC. Le dernier chapitre esquisse une formalisation des circuits digitaux via un plongement profond utilisant les types dépendants de Coq ; on s'intéresse ensuite à prouver la correction totale de circuits paramétriques.

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Bonnet, Jacques. "Analyses structure fonction du module de déubiquitination du complexe SAGA." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00870969.

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Pour faciliter l'initiation de la transcription par l'ARN Polymérase II, le complexe co-activateur de la transcription SAGA possède une activité d'acétylation des histones H3 et une activité de déubiquitination des histones H2B, catalysée chez l'homme par l'enzyme USP22. Mon travail de thèse a porté sur l'étude de la régulation de cette activité de déubiquitination.Au sein de SAGA, USP22 interagit fortement avec trois protéines pour former un module structural appelé module de déubiquitination (DUBm). Nous avons montré que la formation d'un tel module était requise pour activer USP22. D'autre part, deux sous-unités du DUBm humain, ATXN7 et ATXN7L3, contiennent un domaine SCA7. Nos résultats montrent que le repliement structural adopté par ces deux doigts de zinc n'avait pas encore été décrit. Nous avons démontré que le domaine SCA7 de ATXN7 peut interagir avec un nucléosome in vitro et que cette interaction participe à la régulation fine de l'activité de déubiquitination de SAGA. Nous proposons qu'en interagissant avec le nucléosome, le domaine SCA7 de Sgf73 ou de ATXN7 pourrait positionner le DUBm de façon optimale par rapport à son substrat.

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Pham, Trong-Ton. "MODELE DE GRAPHE ET MODELE DE LANGUE POUR LA RECONNAISSANCE DE SCENES VISUELLES." Phd thesis, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00599927.

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Nous présentons une nouvelle méthode pour exploiter la relation entre différents niveaux de représentation d'image afin de compléter le modèle de graphe visuel. Le modèle de graphe visuel est une extension du modèle de langue classique en recherche d'information. Nous utilisons des régions d'images et des points d'intérêts (associées automatiquement à des concepts visuels), ainsi que des relations entre ces concepts, lors de la construction de la représentation sous forme de graphe. Les résultats obtenus sur catégorisation de la collection RobotVision de la compétition d'ImageCLEF 2009 et la collection STOIC-101 montrent que (a) la procédure de l'induction automatique des concepts d'une image est efficace, et (b) l'utilisation des relations spatiales entre deux niveaux de représentation, en plus de concepts, permet d'améliorer le taux de reconnaissance.

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Amez, Lucy. "Tag based Bayesian latent class models for movies : economic theory reaches out to big data science." Thesis, London Metropolitan University, 2017. http://repository.londonmet.ac.uk/1263/.

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For the past 50 years, cultural economics has developed as an independent research specialism. At its core are the creative industries and the peculiar economics associated with them, central to which is a tension that arises from the notion that creative goods need to be experienced before an assessment can be made about the utility they deliver to the consumer. In this they differ from the standard private good that forms the basis of demand theory in economic textbooks, in which utility is known ex ante. Furthermore, creative goods are typically complex in composition and subject to heterogeneous and shifting consumer preferences. In response to this, models of linear optimization, rational addiction and Bayesian learning have been applied to better understand consumer decision- making, belief formation and revision. While valuable, these approaches do not lend themselves to forming verifiable hypothesis for the critical reason that they by-pass an essential aspect of creative products: namely, that of novelty. In contrast, computer sciences, and more specifically recommender theory, embrace creative products as a study object. Being items of online transactions, users of creative products share opinions on a massive scale and in doing so generate a flow of data driven research. Not limited by the multiple assumptions made in economic theory, data analysts deal with this type of commodity in a less constrained way, incorporating the variety of item characteristics, as well as their co-use by agents. They apply statistical techniques supporting big data, such as clustering, latent class analysis or singular value decomposition. This thesis is drawn from both disciplines, comparing models, methods and data sets. Based upon movie consumption, the work contrasts bottom-up versus top-down approaches, individual versus collective data, distance measures versus the utility-based comparisons. Rooted in Bayesian latent class models, a synthesis is formed, supported by the random utility theory and recommender algorithm methods. The Bayesian approach makes explicit the experience good nature of creative goods by formulating the prior uncertainty of users towards both movie features and preferences. The latent class method, thus, infers the heterogeneous aspect of preferences, while its dynamic variant- the latent Markov model - gets around one of the main paradoxes in studying creative products: how to analyse taste dynamics when confronted with a good that is novel at each decision point. Generated by mainly movie-user-rating and movie-user-tag triplets, collected from the Movielens recommender system and made available as open data for research by the GroupLens research team, this study of preference patterns formation for creative goods is drawn from individual level data.

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Nepali, Anjeev. "County Level Population Estimation Using Knowledge-Based Image Classification and Regression Models." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc30498/.

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This paper presents methods and results of county-level population estimation using Landsat Thematic Mapper (TM) images of Denton County and Collin County in Texas. Landsat TM images acquired in March 2000 were classified into residential and non-residential classes using maximum likelihood classification and knowledge-based classification methods. Accuracy assessment results from the classified image produced using knowledge-based classification and traditional supervised classification (maximum likelihood classification) methods suggest that knowledge-based classification is more effective than traditional supervised classification methods. Furthermore, using randomly selected samples of census block groups, ordinary least squares (OLS) and geographically weighted regression (GWR) models were created for total population estimation. The overall accuracy of the models is over 96% at the county level. The results also suggest that underestimation normally occurs in block groups with high population density, whereas overestimation occurs in block groups with low population density.

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Bouhalli, Nadia. "Etude et intégration de convertisseurs multicellulaires parallèles entrelacés et magnétiquement couplés." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2009. http://tel.archives-ouvertes.fr/tel-00554341.

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L'apparition de convertisseurs multicellulaires parallèles entrelacés et magnétiquement couplés a conduit ces dernières années à améliorer les performances des convertisseurs (densité de puissance, efficacité, dynamique,...). Il existe plusieurs topologies d'entrelacement qui utilisent des Transformateurs Interphases. L'objectif principal de cette étude est de trouver parmi ces topologies celles qui sont les mieux adaptées à un contexte d'intégration d'électronique de puissance pour minimiser la taille et réduire les pertes. Une première étape de modélisation a permis d'effectuer une étude comparative de quelques topologies. Un procédé de permutation des phases d'alimentation a été présenté afin de réduire les ondulations du courant de phases et les pertes ohmiques. Les résultats obtenus valident qualitativement l'avantage de la solution retenue par rapport à la solution standard. Enfin, la réalisation pratique d'un prototype de convertisseur modulaire utilisant des Transformateurs Inter-phases est abordé. Il s'agit d'un régulateur chargé d'alimenter les microprocesseurs (1,2V/100A) (Voltage Regulator Module (VRM)) à 5 modules. Les résultats expérimentaux montrent l'avantage de l'utilisation des Transformateurs Inter-phases par rapport à la solution classique.

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Habarulema, John Bosco. "A contribution to TEC modelling over Southern Africa using GPS data." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1005241.

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Modelling ionospheric total electron content (TEC) is an important area of interest for radio wave propagation, geodesy, surveying, the understanding of space weather dynamics and error correction in relation to Global Navigation Satellite Systems (GNNS) applications. With the utilisation of improved ionosonde technology coupled with the use of GNSS, the response of technological systems due to changes in the ionosphere during both quiet and disturbed conditions can be historically inferred. TEC values are usually derived from GNSS measurements using mathematically intensive algorithms. However, the techniques used to estimate these TEC values depend heavily on the availability of near-real time GNSS data, and therefore, are sometimes unable to generate complete datasets. This thesis investigated possibilities for the modelling of TEC values derived from the South African Global Positioning System (GPS)receiver network using linear regression methods and artificial neural networks (NNs). GPS TEC values were derived using the Adjusted Spherical Harmonic Analysis (ASHA) algorithm. Considering TEC and the factors that influence its variability as “dependent and independent variables” respectively, the capabilities of linear regression methods and NNs for TEC modelling were first investigated using a small dataset from two GPS receiver stations. NN and regression models were separately developed and used to reproduce TEC fluctuations at different stations not included in the models’ development. For this purpose, TEC was modelled as a function of diurnal variation, seasonal variation, solar and magnetic activities. Comparative analysis showed that NN models provide predictions of GPS TEC that were an improvement on those predicted by the regression models developed. A separate study to empirically investigate the effects of solar wind on GPS TEC was carried out. Quantitative results indicated that solar wind does not have a significant influence on TEC variability. The final TEC simulation model developed makes use of the NN technique to find the relationship between historical TEC data variations and factors that are known to influence TEC variability (such as solar and magnetic activities, diurnal and seasonal variations and the geographical locations of the respective GPS stations) for the purposes of regional TEC modelling and mapping. The NN technique in conjunction with interpolation and extrapolation methods makes it possible to construct ionospheric TEC maps and to analyse the spatial and temporal TEC behaviour over Southern Africa. For independent validation, modelled TEC values were compared to ionosonde TEC and the International Reference Ionosphere (IRI) generated TEC values during both quiet and disturbed conditions. This thesis provides a comprehensive guide on the development of TEC models for predicting ionospheric variability over the South African region, and forms a significant contribution to ionospheric modelling efforts in Africa.

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Vienney, Mathieu. "Construction de (phi,gamma)-modules en caractéristique p." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2012. http://tel.archives-ouvertes.fr/tel-00763785.

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Cette thèse est constituée de deux parties indépendantes, étudiant deux aspects de la théorie des (φ,Γ)-modules en caractéristique p. La première partie porte sur l'étude de la réduction modulo p des représentations cristallines irréductibles de dimension deux. Nous donnons, pour des poids k ≤ p², un calcul explicite de la réduction de V(k,a) pour a dans un disque fermé centré en zéro, généralisant ainsi des résultats déjà connus pour k ≤ 2p. En particulier, nous calculons le plus grand rayon possible pour ce disque, et montrons que dans certains cas, la réduction qui est constante à l'intérieur du disque change sur son bord. Dans la seconde partie, nous nous intéressons aux représentations d'un sous-groupe de Borel de GL[indice]2(Q[indice]p) sur un corps de caractéristique p, et en particulier à celles qui sont lisses, irréductibles et admettent un caractère central. Une méthode pour construire de telles représentations à partir de (φ,Γ)-modules irréductibles a été décrite par Colmez dans sa construction de la correspondance de Langlands p-adique. Après avoir donné un cadre un peu plus général dans lequel la construction de Colmez fonctionne encore, nous classifions les représentations irréductibles du Borel, prouvant que la construction précédente permet d'obtenir toutes les représentations de dimension infinie. Lorsque le corps des coefficients est fini, ou algébriquement clos, nous disposons d'une interprétation galoisienne des (φ,Γ)-modules irréductibles, et la classification précédente permet alors d'obtenir une correspondance entre ces représentations du Borel et des représentations galoisiennes modulaires.

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Longuevergne, D. "Etude et test d'un module accélérateur supraconducteur pour le projet Spiral2." Phd thesis, Université Paris Sud - Paris XI, 2009. http://tel.archives-ouvertes.fr/tel-00448271.

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Le projet SPIRAL2, en phase de construction au GANIL à Caen, viendra augmenter les capacités de production et d'accélération de l'actuelle installation SPIRAL. Cette extension consiste en la construction d'une zone de production d'isotopes radioactifs associée à un accélérateur linéaire supraconducteur. Ce dernier permet l'accélération de faisceaux de deutons de 5 mA à 40 MeV ainsi que d'une grande variété d'ions (protons, deutons, ions ayant un rapport charge/masse de 1/3) jusqu'à une énergie de 14.5 MeV/u et un courant de 1 mA. Le taux de fission visé (~ 1014 fissions/s) ainsi que cette grande polyvalence d'accélération sont rendus possible grâce à l'utilisation de la technologie supraconductrice. L'étude, la conception et l'intégration des modules accélérateurs supraconducteurs de la partie haute énergie ont été effectuées à l'Institut de Physique Nucléaire d'Orsay (IPNO). Le travail de thèse présenté ici s'inscrit dans ce contexte. Dans un premier temps, les cavités accélératrices supraconductrices de type quart-d'onde ont été validées et caractérisées d'un point de vue électromagnétique et mécanique en cryostat de qualification (-269 °C). Par la suite, un module accélérateur totalement équipé a été qualifié en configuration dite « machine ». Des études plus spécifiques ont également été menées sur l'effet 100K, les microphonies et la caractérisation du système d'accord en fréquence par plongeur mobile, système novateur pour les cavités supraconductrices. La validation des performances du module accélérateur à travers ce travail de thèse a donné lieu au lancement de la phase de fabrication des cavités accélératrices et des cryomodules.

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Gibert, Claude. "Analyse modale non-linéaire expérimentale." Phd thesis, Ecole Centrale de Lyon, 2001. http://tel.archives-ouvertes.fr/tel-00591587.

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L'introduction de l'analyse modale dans le cadre de structures mécaniques non-linéaires semble paradoxale, car le domaine d'application des nombreuses méthodes regroupées sous ce terme, est limité aux systèmes qui peuvent être considérés comme linéaires. Cependant, l'obtention de bases modales par ces méthodes très répandues, est d'une très grande utilité dans le domaine de l'ingénierie à plusieurs égards : caractérisation dynamique des structures, prédiction des réponses, sous-structuration, recalage de modèles... La notion de mode de vibration a été étendue, dans les années 1960, à une certaine classe de systèmes non-linéaires. Les modes des systèmes linéaires sont alors un cas particulier des modes normaux non-linéaires définis comme des mouvements possédant des propriétés particulières et dont l'existence a été démontrée. Depuis, de nombreux développements, le plus souvent analytiques, ont été effectués dans l'étude des systèmes dynamiques à l'aide des modes normaux non-linéaires. Les structures réelles exhibent souvent des comportements non-linéaires et peuvent donc poser certains problèmes de modélisation et d'analyse. Il nous a semblé opportun de rechercher l'intérêt, les possibilités d'application et l'efficacité de méthodes basées sur des notions modales étendues au cas non-linéaire dans un contexte expérimental et industriel. Dans le cadre de ce travail, des méthodes de calcul des modes non-linéaires sont évaluées sur des modèles numériques de structures. Des techniques d'identification des modes non-linéaires dans le domaine fréquentiel sont proposées, appliquées à des cas expérimentaux puis industriels, sur lesquels auront été effectués des tests vibratoires adéquats. Nous montrons quelques possibilités dans le domaine de l'analyse expérimentale des structures vibrantes basée sur des notions modales non-linéaires.

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Mercat, Christian. "Holomorphie discrete et modele d'ising." Strasbourg 1, 1998. https://tel.archives-ouvertes.fr/tel-00001851.

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Ma these generalise la notion de criticalite pour le modele d'ising en dimension 2. J'y definis une nouvelle notion d'holomorphie discrete sur une decomposition cellulaire d'une surface de riemann. Le modele d'ising converge, a imite thermodynamique vers une theorie conforme continue, quand la limite est prise sur un reseau (carre, triangulaire), pres de la temperature critique. J'etends cette criticalite a des decompositions cellulaires generales et je decompose le spineur en parties holomorphes et anti-holomorphes discretes, analogues discrets des blocs conformes. On definit une equation de cauchy-riemann discrete sur le double d'une decomposition cellulaire. Des theoremes classiques sont encore transposables : harmonicite, base des differentielles, pole, theoreme des residus. Il y a des differences, le produit point par point ne preserve pas l'holomorphie, les poles sont d'ordre un, l'espace des formes holomorphes est de dimension double du genre. Une carte est semi-critique si d'une fonction holomorphe discrete f et d'une carte locale plate z on peut faire une 1-forme fdz et critique si fdz est holomorphe. Cette classe contient les reseaux mais bien plus. Une suite convergente de fonctions holomorphes discretes sur une suite convergente de cartes critiques a pour limite une fonction holomorphe sur la surface de riemann. Dans le cas des reseaux triangulaires et carres, on demontre que la criticalite statistique d'ising equivaut a notre criticalite pour une structure conforme reliee aux constantes d'interaction. On definit une equation de dirac sans masse, l'existence d'une solution equivaut a la criticalite. Le spineur de dirac permet alors de decomposer le fermion d'ising en une partie holomorphe et une partie antiholomorphe.

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Dissertations / Theses on the topic 'Moduli TEG'

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