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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.
161

Encoding information structure in Yucatec Maya : on the interplay of prosody and syntax

Kügler, Frank, Skopeteas, Stavros, Verhoeven, Elisabeth January 2007 (has links)
The aim of this paper is to outline the means for encoding information structure in Yucatec Maya. Yucatec Maya is a tone language, displaying a three-fold opposition in the tonal realization of syllables. From the morpho-syntactic point of view, the grammar of Yucatec Maya contains morphological (topic affixes, morphological marking of out-of-focus predicates) and syntactic (designated positions) means to uniquely specify syntactic constructions for their information structure. After a descriptive overview of these phenomena, we present experimental evidence which reveals the impact of the nonavailability of prosodic alternatives on the choice of syntactic constructions in language production.
162

Initial-boundary value problems in fluid dynamics modeling

Zhao, Kun 31 August 2009 (has links)
This thesis is devoted to studies of initial-boundary value problems (IBVPs) for systems of partial differential equations (PDEs) arising from fluid mechanics modeling, especially for the compressible Euler equations with frictional damping, the Boussinesq equations, the Cahn-Hilliard equations and the incompressible density-dependent Navier-Stokes equations. The emphasis of this thesis is to understand the influences to the qualitative behavior of solutions caused by boundary effects and various dissipative mechanisms including damping, viscosity and heat diffusion.
163

Professionellas uppfattning om användbarheten av en checklista (Check: IRK) för initial riskbedömning av riskfaktorer för kriminalitet / How professional find the usability of a checklist (Check: IRK) for initial risk assessment of risk factors for criminal behavior

Rehnvall, Malin, Strand, Johanna January 2014 (has links)
Check: IRK (Initial Riskbedömning för Kriminalitet) är en nyutvecklad evidensbaserad checklista tänkt att användas av professionella i initiala bedömningar för att identifiera riskfaktorer för kriminalitet hos ungdomar och vuxna med risk för långvarigt kriminellt beteende. Syftet med vår studie var att i en första pilottestning ta reda på hur professionella inom polis och socialtjänst uppfattar användbarheten av Check: IRK. Via en webbenkätundersökning besvarade 21 respondenter, varav 6 män och 15 kvinnor mellan 26-47 år (M=36 år, SD=6,70) på frågor gällande innehåll, tillämpning och utbildning i Check: IRK. Studiens data analyserades med Z-test och resultaten indikerar att utifrån innehåll, tillämpning och utbildning i checklistan så uppfattar professionella inom polis och socialtjänst Check: IRK som användbar i sitt arbete. / Check: IRK is a newly developed evidence-based checklist designed to be used by professionals in the initial assessment to identify risk factors for criminality in adolescents and adults at risk of long-term criminal behavior. The current pilot study investigated how professionals within the police and social services perceived the usefulness of Check: IRK. Through a web survey 21 respondents including 6 men and 15 women between the age of 26-47 years (M=36 years, SD=6,70) answered questions regarding the content, implementation and training of the Check: IRK. Data were analyzed using Z-test and the results indicated that professionals within the police and social services find the Check: IRK to be useful in their daily work.
164

Do Innovative Firms Leave More Money on the Table?

Wigren, Anna, Rådman, Tobias January 2021 (has links)
This study examines the relationship between firm innovation and Initial Public Offering (IPO) underpricing in the Swedish stock market by examining 287 firms that went public on the Nasdaq OMX Stockholm and Nasdaq First North during the years 2010 – 2020. An OLS regression model is utilized to analyze the relationship between underpricing, measured as the initial returns, and firm innovation, measured as patents and Research and Development (R&D). The average initial returns for the sample were (+8,16 %) showing that IPOs are, on average, underpriced in the Swedish stock market. While the connection between patents and underpricing was negligible, the results indicated that firms that reported R&D expenditures separately, specifying how much of their expenditures were spent on R&D, experienced a small decrease in IPO underpricing. Also, a slightly larger decrease in IPO underpricing was found for the firms that both had patents and reported their IPO expenditures separately. Thus, these results indicate that firms with a higher level of innovation are “leaving less money on the table”.
165

Convergence Properties for Different Null Space Bases When Solving the Initial Margin Optimization Problem Using CMA-ES / Konvergens för olika nollrumsrepresentationer vid optimering av inital margin med CMA-ES

Barnholdt, Jacob, Carlsson, Filip January 2020 (has links)
This thesis evaluates how the evolutionary algorithm CMA-ES (Covariance Matrix Adaption Evolution Strategy) can be used for optimizing the total initial margin for a network of banks trading bilateral OTC derivatives. The algorithm is a stochastic method for optimization of non-linear and, but not limited to, non-convex functions. The algorithm searches for an optimum by generating normally distributed samples and iteratively updating the mean and covariance matrix of the search distribution using the best candidate solutions in the sampled population. In this thesis, feasible solutions are represented by the null space obtained from the constraint of keeping all banks' market exposure unchanged throughout the optimization, and the generated samples for each iteration correspond to linear combinations of the base vectors spanning this null space. In particular, this thesis investigates how different representations of this null space affect the convergence speed of the algorithm. By applying the algorithm to problems of varying sizes, using several different null space representations coming from different matrix decomposition methods, it is found that as long as an orthonormal representation is used it does not matter which matrix decomposition method it comes from. This is found to be because, given any orthonormal null space representation, the algorithm will at start generate a rotationally invariant sample space in its search for the optimal solution, independent of the specific null space representation. If the representation is not orthogonal, the initial sample will in contrast be in the shape of an ellipsoid and thus biased in certain directions, which in general affects the performance negatively. A non-orthonormal representation can converge faster in specific optimization problems, if the direction of the solution is known in advance and the sample space is pointed towards that direction. However, the benefit of this aspect is limited in a realistic scenario and an orthonormal representation is recommended. Furthermore, as it is shown that different orthonormal representations perform equally, it is implied that other characteristics can be considered when deciding which matrix decomposition method to use; such as the importance of fast computation or desire for a sparse representation. / Denna avhandling utvärderar hur CMA-ES (Covariance Matrix Adaption Evolution Strategy) kan användas för att optimera en total "initial margin" för ett nätverk av banker som handlar bilaterala OTC derivat. Algoritmen är en stokastisk metod för optimering av icke-linjära och, men inte enbart, icke-konvexa funktioner. Algoritmen söker efter ett optimum genom att generera normalfördelade utfall och iterativt uppdatera medelvärdet och kovariansmatrisen för sök-fördelningen med hjälp av de bästa lösningarna i varje iteration. I detta arbete representeras tillåtna lösningar till problemet av nollrummet från bivillkoret att alla bankers marknadsexponering ska vara oförändrade genom optimeringen och de genererade utfallen består av slumpade linjärkombinationer av nollrummets basvektorer. I synnerhet undersöks hur olika representationer av nollrummet påverkar konvergenshastigheten för algoritmen. Algoritmen har applicerats med flera olika nollrumsrepresentationer, framtagna genom olika matrisfaktoriseringsmetoder, och det kan konstateras att så länge nollrummsrepresentationen är ortonormal är valet av faktoreringsmetod obetydlig. Detta då användande av orthornormala nollrumsrpresentationer i algoritmen leder till en initialt symmetrisk, rotationsmässigt invariant, sökning efter den optimala lösningen. Om representationen inte är ortogonal kommer det resulterande sökområdet i varje iteration att ha formen av en ellipsoid och sålunda viktas i vissa riktningar, vilket i allmänhet påverkar prestandan negativt. Emellertid kan en icke-ortonormal representation konvergera snabbare i specifika scenarier, givet att lösningens riktning är känd i förväg och sökområdet kan pekas mot den riktningen. Vidare, eftersom det har visats att olika ortonormala representationer konvergerar lika fort, innebär resultatet att andra egenskaper kan beaktas vid val av matrisfaktoriseringsmetod, såsom vikten av snabb beräkning eller önskan om en gles representation.
166

Initial Token Offerings, Friend or Foe? : A qualitative study of capital procurement using initial token offerings / Kapitalanskaffning och kryptovalutor : En kvalitativ studie av kapitalanskaffning med initial token offerings

Gileborg, Robin January 2018 (has links)
This thesis investigates the emerging phenomenon of Initial Token Offerings, which is a tool for capital procurement for ventures being built using token ecosystems within their products. Through a series of interviews with representatives from venture capital, blockchain specialized venture capital, investors, and academia, the author connects the sentiments held by those representatives to the existing literature of behavioral economics. The sentiments expressed mainly focus on: the role of regulations; the development of investors during capital procurement; and the potential for experimentation in the field of token economies. The thesis discusses the implications of the technologies and potential future outcomes. The author also raises the question of whether this is the first non-regulated financial ecosystem that could provide an interesting perspective for behavioral economists as future research is done on the effects of regulations. / Den här uppsatsen undersöker det nya fenomenet Intial Token Offerings, ett verktyg för kapitalanskaffning för bolag som bygger produkter med en kryptografisk token ekonomi som en del av sin plattform. Genom en serie intervjuer med representanter från riskkapital, blockkedjespecialiserat riskkapital, investerare och forskare försöker författaren koppla de koncept och tendenser som tas upp i intervjuerna till fältet beteendeekonomi. The koncept som tog upps består till största del av: den roll regulatoriska aspekter kan spela; utvecklingen av investerarens roll vid kapitalanskaffning; och vikten av fortsatt experimentation gällande finansieringsmodeller inom krypografiska tillgångar och plattformar. Uppsatsen diskuterar också implikationer och möjliga framtida resultat. Författaren lyfter också frågan om kryptografiska tillgångar ger forskare en unik möjlighet att studera effekterna av individers tendenser och regulatorisk påverkan ur ett beteendeekonomiskt perspektiv.
167

Generic Distractions and Strata of Hilbert Schemes Defined by the Castelnuovo-Mumford Regularity

Anna-Rose G Wolff (13166886) 28 July 2022 (has links)
<p>Consider the standard graded polynomial ring in $n$ variables over a field $k$ and fix the Hilbert function of a homogeneous ideal. In the nineties Bigatti, Hulett, and Pardue showed that the Hilbert scheme consisting of all the homogeneous ideals with such a Hilbert function contains an extremal point which simultaneously maximizes all the graded Betti numbers. Such a point is the unique lexsegment ideal associated to the fixed Hilbert function.</p> <p> For such a scheme, we consider the individual strata defined by all ideals with Castelnuovo-Mumford regularity bounded above by <em>m</em>. In 1997 Mall showed that when <em>k </em>is of characteristic 0 there exists an ideal in each nonempty strata with maximal possible Betti numbers among the ideals of the strata. In chapter 4 of this thesis we provide a new construction of Mall's ideal, extend the result to fields of any characteristic, and show that these ideals have other extremal properties. For example, Mall's ideals satisfy an equation similar to Green's hyperplane section theorem.</p> <p> The key technical component needed to extend the results of Mall is discussed in Chapter 3. This component is the construction of a new invariant called the distraction-generic initial ideal. Given a homogeneous ideal <em>I C S</em> we construct the associated distraction-generic initial ideal, D-gin<sub><</sub> (<em>I</em>), by iteratively computing initial ideals and general distractions. The result is a monomial ideal that is strongly stable in any characteristic and which has many properties analogous to the generic initial ideal of <em>I</em>.</p>
168

Reverse engineering of heavy-ion collisions : unraveling initial conditions from anisotropic flow data / Rétro-ingénierie des collisions d'ions lourds : contraindre l’état 
initial à partir des données de flot anisotrope

Retinskaya, Ekaterina 10 June 2014 (has links)
La physique des collisions d'ions lourds réunit deux domaines : la physique nucléaire et la physique des particules. Les progrès expérimentaux de ces dernières années donne l'opportunité d'étudier la nouvelle matière créée dans les collisions d'ions lourds qui s'appelle le plasma de quarks et de gluons.L'état initial de deux ions qui se collisionnent est affecté par les fluctuations créées par les fonctions d'ondes des nucléons. Ces fluctuations provoquent l'anisotropie de moments de la matière hadronique observée par les détecteurs. Le système créé dans une collision se comporte comme un fluide, donc l'état initial est connecté avec l'état final par l'évolution hydrodynamique. L’hydrodynamique relativiste est utilisée pour décrire l'évolution du fluide créé dans les collisions d'ions lourds. Nos résultats combinés avec les données expérimentales permettent de contraindre l'etat initial donc de faire la «rétro-ingénierie» des collisions d'ions lourds.L'observable qui caractérise l'anisotropie des moments est le flot anisotrope v_n. On présente les premières mesures du premier coefficient de la distribution de Fourier v_1 pour l'accélérateur LHC. v_1 s'appelle le flot dirigé. On effectue aussi les premiers calculs de v_1 à partir de l’hydrodynamique visqueuse. On trouve que v_1 est moins dépendent de la viscosité que les coefficients v_2 et v_3 qui sont respectivement les flots elliptique et triangulaire. On présente aussi les prédictions de v_1 pour l'accélérateur RHIC. Ces résultats ont été confirmés plus tard par les mesures de v_1 par RHIC. On propose aussi deux méthodes pour contraindre les modèles d’état initial: avec les données de v_1 et les données de v_2 et v_3. Ces méthodes donnent l'unique possibilité de contraindre les modèles Monte Carlo d'état initial. A la fin de cette thèse on montre les perspectives de ce domaine et on étudie les corrélations entre les plans des évènements qui ont été mesurées récemment et qui pourraient faire la lumière sur les fluctuations de l'état initial. / Ultra-Relativistic heavy-ion physics is a promising field of high energy physics connecting two fields: nuclear physics and elementary particle physics. Experimental achievements of the last years have provided an opportunity to study the properties of a new state of matter created in heavy-ion collisions called quark-gluon plasma. The initial state of two colliding nuclei is affected by fluctuations coming from wave- functions of nucleons. These fluctuations lead to the momentum anisotropy of the hadronic matter which is observed by the detectors. The system created in the collision behaves like a fluid, so the initial state is connected to the final state via hydrodynamic evolution. In this thesis we model the evolution with relativistic viscous hydrodynamics. Our results, combined with experimental data, give non trivial constraints on the initial state, thus achieving "reverse engineering" of the heavy-ion collisions. The observable which characterizes the momentum anisotropy is the anisotropic flow vn. We present the first measurements of the first harmonic of the anisotropic flow called directed flow v1 in Pb-Pb collisions at the LHC. We then perform the first viscous hydrodynamic modeling of directed flow and show that it is less sensitive to viscosity than higher harmonics. Comparison of these experimental data with the modeling allows to extract the values of the dipole asymmetry of the initial state, which provides constraints on the models of initial states. A prediction for directed flow v1 in Au-Au collisions is also made for RHIC. We then perform a similar modeling of the second and third harmonics of the anisotropic flow, called respectively elliptic v2 and triangular v3 flow. A combined analysis of the elliptic and triangular flow data compared with viscous hydrodynamic calculations allows us to put constraints on initial ellipticity and triangularity of the system. These constraints are then used as a filter for different models of initial state. At the end of this thesis, we show perspectives in the studies of the initial state which are opened by recent measurements of event-plane correlations which could shed light on the initial state fluctuations.
169

Etude des mécanismes d'adressage et de positionnement de l'ankyrine G et de la protéine kinase CK2 au segment initial de l'axone / Identification of the mecanisms regulating the trafficking and positioning of ankyrin G and protein kinase CK2 at the axon initial segment

Hien, Yéri Esther 16 July 2014 (has links)
Le segment initial de l'axone (SIA) joue un rôle dans la maintenance de la polarité neuronale et dans l'initiation du potentiel d'action. Il se construit autour de l'ankyrine G (ankG) qui relie les protéines membranaires au cytosquelette d'actine et de microtubules. Cette structure est dynamiquement régulée par des kinases. S'il a été clairement établi que l'ankG est cruciale à la formation et à la maintenance du SIA, les mécanismes responsables de sa concentration dans la partie proximale de l'axone restent encore inconnus. Il en est de même pour la protéine kinase CK2 qui régule l'interaction entre l'ankG et les canaux sodiques (Nav1). Dans un premier temps, nous avons montré, par des approches de mutagénèse, que le domaine serine-rich (SR), notamment ses 73 premiers acides aminés, porte l'information nécessaire à l'entrée de l'ankG dans l'axone. Mais ce domaine n'est pas suffisant pour le confiner dans la partie proximale de l'axone, cette propriété est portée par le domaine Tail. En plus de la coopération de ces domaines, nous avons aussi observé que l'adressage de l'ankG est régulé par les kinases Cdk5 et PKC. Dans un second temps, nous avons montré que l'accumulation de la CK2 au SIA dépend de l'expression des Nav1. L'existence d'un complexe formé par les Nav1 et la CK2 serait donc importante au recrutement de la protéine kinase CK2 au SIA. En outre, le développement des anticorps phosphospécifiques nous a permis de monter que les Nav1 sont phosphorylés in vivo au niveau de leur motif de liaison à l'ankG. L'ensemble de nos résultats ouvre de nouvelles perspectives dans la compréhension de la formation du SIA et des mécanismes de régulation qui peuvent être associés. / The axon initial segment (AIS) is responsible for both the maintenance of neuronal polarity and the generation of action potentials. The scaffolding protein ankyrin G (ankG) is specifically expressed in the AIS where it links transmembrane proteins to the subjacent actin and microtubule cytosqueletons. Moreover, the AIS is dynamically regulated by kinases. Although, it has been clearly established that ankG directs AIS assembly and maintenance, the mechanisms regulating ankG proper transport and tethering remain unclear. Another AIS component, the protein kinase CK2 is also playing an important role via the phosphorylation of the ankG-binding motif (ABM) on sodium channels (Nav1) to strengthen their interaction with ankG. But, the mechanism regulating its targeting and anchoring to the AIS remain still unknown. Here, we report that the first 73 residues of the serine-rich domain are necessary for the targeting of ankG to the axon and the tail domain for the proper positioning along the proximal axon. We also observed that ankG axonal localization is modulated by post-translational modifications. Using phosphospecific antibodies and inhibition/depletion approaches, we also provide evidence that the ABM of Nav1 are phosphorylated in vivo and that CK2 accumulation at the AIS depends on Nav1 expression, with which they form tight complexes. This suggests that CK2-mediated phosphorylation participates in Nav1 clustering in vivo and that its specific localization at the AIS is dependent on Nav1 expression. Altogether, our results open new perspectives in understanding the formation of AIS and regulatory mechanisms that may be involved.
170

A política pública de formação de professores na prática pedagógica do professor iniciante de Educação Física do Município de Lajeado

Rocha, Leandro Oliveira January 2014 (has links)
O presente estudo, de natureza qualitativa, tematiza a política pública e tem como problema de pesquisa: como a política pública de formação de professores vigente é concretizada no trabalho docente do professor iniciante de Educação Física da Educação Básica de Lajeado? Trata-se de uma etnografia realizada em três escolas do município de Lajeado/RS com três professores iniciantes de Educação Física. Visando compreender os efeitos da política pública de formação de professores no trabalho docente e nas práticas pedagógicas dos colaboradores da pesquisa, foi descrito o cotidiano de trabalho desses professores e analisado suas concepções acerca da formação inicial, da docência e do trabalho na escola, bem como os aprendizados construídos nesses primeiros anos de suas vidas profissionais. O trabalho de campo teve duração de seis meses e possibilitou a construção de quatro categorias de análise, que emergiram, principalmente, dos registros das observações, diálogos e entrevistas semiestruturadas realizadas com os colaboradores e da revisão de literatura acerca dos aspectos que constituem o problema de pesquisa. As discussões e interpretações suscitadas pela análise permitiram compreender que a política pública de formação de professores influencia o contexto social mais amplo e a singularidade dos processos formativos. Desse modo, suas influencia atingem os entornos da profissão docente, a formação inicial e as expectativas profissionais desses professores iniciantes. No entanto, partindo do entendimento sobre problema público e que um dos propósitos da política pública de formação de professores é melhorar a qualidade da Educação Básica, foi possível identificar que essa meta não é concretizada no trabalho docente dos professores colaboradores. Isso porque a identidade docente construída na formação inicial e almejada pela política pública de formação de professores contrasta com a singularidade da cultura escolar das escolas pesquisadas, ou seja, as relações estabelecidas na escola, com outros professores e com as equipes diretivas, tornam-se mais significativas. Tal contraste, mobiliza o isolamento e individualismo dos professores colaboradores, bem como a falta de acompanhamento e retro informação. Os efeitos desse quadro são práticas educativas desconectado da propostas da escola, sem planejamento coletivo nem colegialidade e a forma como as aulas de Educação Física vão, aos poucos, perdendo sua eficácia pedagógica. Ao observar a ineficiência dos atuais programas políticos que constituem a política pública de formação de professores, em vistas ao aumento da qualidade da Educação Básica, ao final do estudo são indicadas três proposições com o intuito de reverter esse quadro. Tais proposições, devem ser compreendidas como possibilidades de fomentar pequenas comunidades de aprendizagem na escola, auxiliar o professor iniciante e contribuir na construção de identidades docentes marcadas pela resiliência e rigorosidade metódica; bem como concretizar a melhoria da qualidade da Educação Básica e, como isso, resgatar o caráter identitário da política pública: promover transformações sociais para o bem social. / The current qualitative study focuses on public policy and the research problem which is how current public policy of teacher formation is carried out during teaching activity performed by Physical Education initial teachers in Elementary Schools of Lajeado. The ethnographic study was carried out with three Physical Education initial teachers. In order to understand the effects of public policy for teacher’s training in teaching and pedagogical activities of those teachers, their daily activities were described and their conceptions about initial training, teaching, school work as well as learning constructed in the first years of professional life were analyzed. The six months field study allowed the presentation of four categories of analysis which mainly emerged from the records of observations, dialogs, and semi-structured interviews carried out with teachers and theory review on aspects that make up the research problem. Through discussions and interpretations raised by analysis it was possible to understand that the public policy of teacher’s formation influences a broader social context and the uniqueness of formation processes. Such influence thus affects the environment of teaching activity, the initial training and professional expectations of initial teachers. From the assumption that public problems to be faced by public policy of teacher training is to improve the quality of Elementary Education, it was found out that such goal is not achieved by the study group teachers. It results from teacher’s identity built on initial training and desired by public policy for teacher formation which contrasts with the uniqueness of school culture of surveyed schools, i.e. relations established in schools with other teachers and with the policy teams become more meaningful. Such contrast leads to isolation and individualism of teachers as well as the lack of monitoring and retro information. The effects of such panorama are educational practices disconnected from school proposal, no collective planning or discussion by teacher’s board, and Physical Education classes gradually losing pedagogical effectiveness. While observing the inefficiency of current political programs that constitute the public policy of teacher’s formation regarding to public problem previously identified, three propositions to reverse such scenery are presented at the end of study. Such propositions must be understood as possibilities of promoting small school learning communities, assisting initial teachers and contributing for the construction of teacher’s identity marked by precise and enforced methodology as well as contribute for the improvement of Elementary Education quality besides converting to identity intensification of public policy which is to promote social changes for the social welfare.

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