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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.
101

Théorie des modèles d'expansions de corps valués : phénomènes de séparation / Model theory of expansions of valued fields : separation phenomena

Rioux, Romain 18 September 2017 (has links)
Cette thèse est consacrée à l'étude d'un point de vue modèle théorique de corps valués algébriquement clos enrichis d'un prédicat qui représente soit un sous-groupe multiplicatif soit un sous-corps. Nous donnons un résultat d'élimination partielle des quantificateurs pour les structures du type (M , G), où M est un corps valué algébriquement clos et où G un sous-groupe multiplicatif sur lequel la valuation est injective... / This thesis is dedicated to the model theoretic study of algebraically closed valued fields equipped with a additional unary predicate for either a multiplicative subgroup or a subfield.We give a result of relative quantifier elimination for structures of the kind (M , G), where M is an algebraically closed valued field and G is a multiplicative subgroup on wich the valuation is injective...
102

Ax-Schanuel type inequalities in differentially closed fields

Aslanyan, Vahagn January 2017 (has links)
In this thesis we study Ax-Schanuel type inequalities for abstract differential equations. A motivating example is the exponential differential equation. The Ax-Schanuel theorem states positivity of a predimension defined on its solutions. The notion of a predimension was introduced by Hrushovski in his work from the 1990s where he uses an amalgamation-with-predimension technique to refute Zilber's Trichotomy Conjecture. In the differential setting one can carry out a similar construction with the predimension given by Ax-Schanuel. In this way one constructs a limit structure whose theory turns out to be precisely the first-order theory of the exponential differential equation (this analysis is due to Kirby (for semiabelian varieties) and Crampin, and it is based on Zilber's work on pseudo-exponentiation). One says in this case that the inequality is adequate. Thus, by an Ax-Schanuel type inequality we mean a predimension inequality for a differential equation. Our main question is to understand for which differential equations one can find an adequate predimension inequality. We show that this can be done for linear differential equations with constant coefficients by generalising the Ax-Schanuel theorem. Further, the question turns out to be closely related to the problem of recovering the differential structure in reducts of differentially closed fields where we keep the field structure (which is quite an interesting problem in its own right). So we explore that question and establish some criteria for recovering the derivation of the field. We also show (under some assumptions) that when the derivation is definable in a reduct then the latter cannot satisfy a non-trivial adequate predimension inequality. Another example of a predimension inequality is the analogue of Ax-Schanuel for the differential equation of the modular j-function due to Pila and Tsimerman. We carry out a Hrushovski construction with that predimension and give an axiomatisation of the first-order theory of the strong Fraïssé limit. It will be the theory of the differential equation of j under the assumption of adequacy of the predimension. We also show that if a similar predimension inequality (not necessarily adequate) is known for a differential equation then the fibres of the latter have interesting model theoretic properties such as strong minimality and geometric triviality. This, in particular, gives a new proof for a theorem of Freitag and Scanlon stating that the differential equation of j defines a trivial strongly minimal set.
103

Groupes hyperboliques et logique du premier ordre / Hyperbolic groups and first-order logic

André, Simon 15 July 2019 (has links)
Deux groupes sont dits élémentairement équivalents s'ils satisfont les mêmes énoncés du premier ordre dans le langage des groupes. Aux environs de l'année 1945, Tarski posa la question suivante, connue désormais comme le problème de Tarski : les groupes libres non abéliens sont-ils élémentairement équivalents ? Une réponse positive à cette fameuse question fut apportée plus d'un demi-siècle plus tard par Sela, et en parallèle par Kharlampovich et Myasnikov, comme le point d'orgue de deux volumineuses séries de travaux. Dans la foulée, Sela généralisa aux groupes hyperboliques sans torsion, dont les groupes libres sont des représentants emblématiques, les méthodes de nature géométrique qu'il avait précédemment introduites à l'occasion de son travail sur le problème de Tarski. Les résultats rassemblés ici s'inscrivent dans cette lignée, en s'en démarquant toutefois dans la mesure où ils traitent des théories du premier ordre des groupes hyperboliques en présence de torsion. Dans un premier chapitre, on démontre, entre autres, que tout groupe de type fini qui est élémentairement équivalent à un groupe hyperbolique est lui-même hyperbolique. On démontre ensuite que les groupes virtuellement libres sont presque homogènes, ce qui signifie que deux éléments qui sont indiscernables du point de vue de la logique du premier ordre sont dans la même orbite sous l'action du groupes des automorphismes du groupe ambiant, à une indétermination finie près. Enfin, on donne une classification complète des groupes virtuellement libres de type fini du point de l'équivalence élémentaire à deux quantificateurs. / Two groups are said to be elementarily equivalent if they satisfy the same first-order sentences in the language of groups, that is the same mathematical statements whose variables are only interpreted as elements of a group. Around 1945, Tarski asked the following question : are non-abelian free groups elementarily equivalent? An affirmative answer to this famous Tarski's problem was given in 2006 by Sela and independently by Kharlampovich and Myasnikov, as the culmination of two voluminous series of papers. Then, Sela gave a classification of all finitely generated groups that are elementarily equivalent to a given torsion-free hyperbolic group. The results contained in the present thesis fall into this context and deal with first-order theories of hyperbolic groups with torsion. In the first chapter, we prove that any finitely generated group that is elementarily equivalent to a hyperbolic group is itself a hyperbolic group. Then, we prove that virtually free groups are almost homogeneous, meaning that elements are almost determined up to automorphism by their type, i.e. the first-order formulas they satisfy. In the last chapter, we give a complete classification of finitely generated virtually free groups up to elementary equivalence with two quantifiers.
104

Μια μπουλιανή γενίκευση της απειροστικής ανάλυσης με εφαρμογές στα ασαφή σύνολα / A boolean generalization of non standard analysis with applications to fuzzy sets

Μαρκάκης, Γεώργιος 06 May 2015 (has links)
Στη διατριβή αυτή θα ασχοληθούμε με την Μπουλιανή ανάλυση σαν μια κατ'ευθείαν γενίκευση της μη συμβατικής ανάλυσης του Robinson, δηλ. της θεωρίας των Υπεργινομένων και τις εφαρμογές της στη θεωρία των Ασαφών συνόλων. / --
105

Arguments and Adjuncts at the Syntax-Semantics Interface / Argumente und Adjunkte an der Syntax-Semantik-Schnittstelle

Schäfer, Roland 11 August 2008 (has links)
No description available.
106

Evolutionäre Referenzmodelle

Lehrmann, Sina 15 September 2014 (has links) (PDF)
Konzeptuelle Modelle sind zur Gestaltung und Steuerung von Informationssystemen ein akzeptiertes und weit verbreitetes Instrument. Sie werden sowohl zur Gestaltung der Organisationsstruktur als auch zur Entwicklung der unterstützenden IT-Systeme verwendet. Für diesen Aufgabenbereich existiert eine hohe Nachfrage nach externer Unterstützung, da spezifische Fachkenntnisse und Erfahrungen notwendig sind. In diesem Zusammenhang werden seit Jahrzehnten Ansätze zur Wiederverwendung in Wissenschaft und Praxis diskutiert. Die Akzeptanz und Verbreitung von explizit zur Wiederverwendung konstruierten Modellen (Referenzmodelle) bleiben jedoch deutlich hinter den Erwartungen zurück. Die vorliegende Arbeit trägt zur Untersuchung möglicher Ursachen für den ausbleibenden Erfolg von Referenzmodellen bei. Der Forschung liegt die Vermutung zugrunde, dass die Potentiale von Referenzmodellen nicht zufriedenstellend ausgeschöpft werden können, weil die existierenden bzw. verwendeten Modellierungsmethoden die theoretischen Anforderungen an die Wiederverwendung von modellhaft dargestellten Lösungen zur Unternehmensgestaltung nicht erfüllen. Die vorliegende Arbeit fasst neun Einzelpublikationen zum Themenbereich Evolutionäre Referenzmodelle zu einer kumulativen Dissertation zusammen. Es werden in einem argumentativdeduktiven Verfahren konstruktivistische Theorien zur systematischen Weiterentwicklung und Wiederverwendung konzeptueller Unternehmensmodelle untersucht. Die auf dieseWeise resultierende Erweiterung der allgemeinen Modelltheorie wurde ihrerseits argumentativ-konzeptionell mit Hilfe von semiformalen Argumentationsmodellen aufbereitet. Im Ergebnis werden ein theoretisches Rahmenwerk zur evolutionären Referenzmodellierung präsentiert und 23 konzeptionelle Anforderungen definiert, die eine gezielte Methodenentwicklung für die evolutionäre Referenzmodellierung steuern sollen.
107

News Propaganda in Poland : Mixed Methods Analysis of the Online News Coverage About the Media Law Proposal Lex TVN

Treichel, Patrycja January 2022 (has links)
The thesis investigates propaganda in the online news coverage about the media law proposal Lex TVN, committed to the Polish parliament in 2021. The mixed methods approach applied in the research is based on a novel analytical matrix combining the Propaganda Model theory (Herman & Chomsky, 1988) and modalities of propaganda techniques (Da San Martino et al., 2020). The main findings indicate that propaganda in the coverage about the Lex TVN is a cross-platform issue; that it occured in different forms, as: sources, critical content (flak) or expressions of ideological preferences; and that it was created using various propaganda techniques. Moreover, the analysis demonstrates that propaganda was used for several reasons: to attract attention of the readers; to increase the firm’s profit and popularity; to express the stance of the media brand towards the bill Lex TVN; and to criticize the current government. The study contributes to the field of Media and Communication Studies by using the novel analytical matrix that tests the applicability of the PM in a new geopolitical context, Poland, and adds to the academically unexplored research area of news propaganda in Polish media. Several topics for further studies are suggested: the analysis of propaganda in the news coverage published by the Polish state media brand TVPInfo; an investigation of the news reception in Poland and the ability of the Polish news readers to identify news propaganda; and lastly, studying potential positive effects of news propaganda in the Polish context.
108

Female Student-Athlete Golfers’ Use of Online Recruiting Platforms to Seek Scholarships: A Global Perspective

Dobele, Linda 01 May 2021 (has links)
The prospective student-athletes’ use of an online recruiting platform to seek college scholarships has become a norm. College coaches recruit prospective-student athletes often using tools like global personal contacts, on-site recruiting, and online recruiting platforms. Online recruiting platforms offer several services and vary in price. This study examines female student-athlete golfers’ use of the online recruiting platform to seek scholarships from a global perspective. Previous research suggests that prospective student-athletes prefer online recruiting platforms while college coaches often use other outlets which can lead to miscommunication and lost opportunities. The services, price, and usability of 20 sports online recruiting platforms in the United States were examined to find out what is offered to prospective-student athletes. Interviews of NCAA Division I collegiate coaches were conducted to examine the most common recruiting tools used by the coaches and their opinions of the use of online recruiting platforms.
109

Psychological adjustment to the onset of rheumatoid arthritis : a longitudinal evaluation of perceptions of, and adherence to, medication

Hughes, Lyndsay Dawn January 2012 (has links)
Rheumatoid arthritis (RA) is a chronic, progressive autoimmune disease causing inflammation of the synovium resulting in severe pain, joint disfigurement and disability as well as malaise, fatigue and a depressed immune system. Treatment consists of three broad phases; firstly, following diagnosis treatment is focussed on rapid reduction of pain and inflammation. Secondly, maintenance of quiescence is sought through medication. Finally, if disease activity remains high despite medication, escalation to anti-TNF α therapy is required to prevent permanent joint damage and disability. The primary course of treatment is prescription of disease modifying anti-rheumatic drugs (DMARDs) within 3 months of onset of symptoms. However, DMARDs can take 8-12 weeks to exhibit a noticeable benefit whereas unpleasant side effects can occur shortly after initiation. Also, DMARDs do not alleviate pain; therefore it is difficult for patients to attribute recovery to this medication. For these reasons, although it is imperative for future health and functioning to take DMARDs as prescribed, non-adherence is common at 30-50%. Non-adherence to treatment can be intentional, where a decision is made not to conform to the prescription, or unintentional which is often due to forgetting. To measure intentional non-adherence, a validated measure of adherence for rheumatoid arthritis was reduced through exploratory factor analysis from 19 items to 5 items by removing items that did not add to the explained variance of adherence. The CQR5 explained 53% of the variance in adherence and was shown to have a good fit to the data through confirmatory factor analysis. A discriminant function equation was generated that correctly identifies 88.5% of patients as high or low adherers and has high clinical utility due to the brevity for patients and unidimensionality for easy interpretation. The CQR5 was used throughout the programme of research to measure intentional non-adherence along with a separate measure of unintentional non-adherence. Four commonly used social cognition models of illness were measured in 227 RA patients to determine which had the best utility for predicting non-adherence to DMARDs. Patients were recruited to represent the three stages of illness including newly diagnosed, established on DMARD therapy and established with concurrent anti-TNF α therapy. Logistic regression analysis showed that the Self Regulatory Model best predicted intentional non-adherence as patients with perceptions of worse consequences of RA and longer disease duration were more likely to be highly adherent to DMARDs in cross-sectional analysis. In contrast, the Theory of Planned Behaviour better predicted patients who self-reported forgetting their DMARDs with patients with more confidence in being able to take their medications (Perceived Behavioural Control) being less likely to forget. 171 patients were successfully followed-up six months after baseline recruitment. The longitudinal results showed that the social cognition models differed for patients at different stages of the illness suggesting that their experience of living with rheumatoid arthritis influenced perceptions of their illness and medications. Newly diagnosed patients scored lower on factors measuring perceptions of disease chronicity and seriousness whereas patients that had escalated to anti-TNF α therapy scored higher on these factors. The newly diagnosed patients also showed more variability in the social cognition scores whereas the more established patients demonstrated stable models of illness. This supports Leventhal’s (1992) theory that illness representations will be regulated through integration of knowledge and experience of an illness. Structural equation modelling was used to establish the best predictors of intentional non-adherence at six month follow-up. In support of research in other chronic illnesses (Horne & Weinman, 2002; Niklas, Dunbar & Wild, 2010), the effect of perceptions of the consequences and chronicity of the illness on adherence are mediated by perceptions of the necessity of the medication. In addition, the impact of the emotional reaction to the illness on adherence to DMARDs is mediated by concerns about the medication. In addition, this study incorporated factors from the Theory of Planned Behaviour to explain medication adherence and found that the influence of friends and family impacts on the patient’s confidence to follow the prescription accurately which in turn as an effect on adherence to DMARDs. This large longitudinal study found that by combining factors from a number of social cognition models, it is possible to explain and predict intentional non-adherence and provides some evidence for best ways to intervene to improve adherence and prognosis. To provide a more comprehensive and clinically useful picture of non-adherence, a Cost of Illness study was carried which found that patients self-reporting low adherence to DMARDs also had significantly higher costs for this medication. This was caused by an increased incidence of Leflunamide prescribing for patients who often forget their medication and was maintained longitudinally. This association has not been previously reported in the literature and provides some evidence that non-adherence to DMARDs is having a concrete effect on the clinical management of patients. Finally, an SMS text message based reminder service designed to remind patients who self-report forgetting their medications was tested through a simulation study for the cost and likely benefit in health related quality of life using the health economic analysis of the longitudinal study and the results of a survey establishing the feasibility of implementing such a service in the rheumatology clinic. A sensitivity analysis testing the number of messages sent and the cost per message found that a reminder service for the sample of patients in this programme of research would cost between £1387.00 and £142.27 per year. This would equate to a cost per Quality Adjusted Life Year (QALY) gain of between £2889.58 and £296.40 by enabling patients to adhere more rigorously to their DMARD regimen. This programme of research is the first to test four commonly used social cognition models to predict adherence to DMARDs in a large, multi-centre longitudinal study of rheumatoid arthritis patients. Perceptions of the likely duration and consequences of the illness, as measured by the Illness Perceptions Questionnaire and the necessity of medications (measured by the Beliefs about Medications Questionnaire) along with self-efficacy (measured by the Theory of Planned Behaviour) explained 24% of the variance in intentional adherence over six months. The results show the importance of considering intentional and unintentional non-adherence separately as they appear to have different underlying mechanisms as well as patients in different phases of the illness as their experience influences their social cognition models of illness. A simple SMS based reminder service could act as a cue to action to reduce unintentional non-adherence whereas addressing issues surrounding maladaptive perceptions about the illness and the treatment could improve intentional non-adherence which has the potential to improve the prognosis and quality of life for patients as well as safe costs for the NHS.
110

VÝZNAM JIHOKOREJSKÝCH INVESTIC V ČR A NA SLOVENSKU V POSLEDNÍM DESETILETÍ / Significance of Korean Foreign Direct Investment in the Czech and Slovak Republic during the last Decade

Patráková, Lenka January 2011 (has links)
The main purpose of this study is to focus on Korean outward foreign direct investment (FDI) in the automotive industry of the Czech and Slovak Republic, and to analyze consequences of Hyundai Motors investment for the Czech national economy. In doing so, this study is divided into the three parts. First theoretical part is concentrated on examination of current trend of FDI flows, its impact on developing and host countries, and theories and models of FDI. Second part is focused on analysis of consequences of investment policy generally. Final part is analyzing Korean, Slovak and Czech automotive industry and the impact of Hyundai Motor Company investment decision for the Czech Republic

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