Cette thèse traite de la reconstruction d'hypersurfaces au sein de champs de normales en dimension quelconque et trouve des applications dans l’analyse des empreintes digitales (lignes dermiques), des images satellites météorologiques (lieux de turbulence) et astrophysiques (bras de galaxies) ainsi que dans l’analyse stratigraphique des images sismiques (horizons). Les méthodes développées s’appuient sur la minimisation d’une équation aux dérivées partielles non linéaire reliant une hypersurface au pendage déduit d’un champ de normales. Elles prennent en compte des contraintes diverses telles que des points de passages, des frontières, des bornes et des discontinuités. La contribution principale de la thèse réside dans l’introduction d’un changement d’espace du pendage qui permet de reconstruire aussi bien des hypersurfaces exprimées sous des formes implicites dans les repères de définition des champs de normales que des horizons sismiques de manière rapide et interactive. Deux schémas de reconstruction d’horizons sismiques unidimensionnels présentant une discontinuité d’amplitude et de lieu inconnus sont également proposés. / This thesis deals with the reconstruction of hypersurfaces from a finite-dimensional normal vector field. Application scopes can be found in the analysis of fingerprints (epidermal ridges), meteorological images (eddies and cyclones), astrophysical images (galaxy arms) and in the stratigraphic analysis of seismic images (horizons). The hypersurfaces are obtained by solving a non-linear partial derivative equation relied on the local dip deduced from a normal vector field. Several constraints such as boundaries, bounds, points belonging to the hypersurface or discontinuities can be considered.The major contribution of this thesis consists in a local dip transformation which allows to reconstruct implicit hypersurfaces as well as seismic horizons by a fast and interactive method. Two schemes dedicated to the reconstruction of discontinuous one-dimensional seismic horizons are also proposed when the discontinuity location and jump are unknown.

In the recent years area organic photovoltaics is generating a lot of interests because whole process of synthesis and fabrication is less energy intensive process as well as it is cost effective compared to conventional inorganic Si based photovoltaic technology. This work mainly deals with the fabrication and optimization of device fabrication conditions for organic photovoltaic materials. In first part of the work, the solar cell fabrication conditions were optimized for the commonly used system P3HT – PCBM. The fabricated device was optimized for the solvents used for the active material, concentration of the active material solution, donor- acceptor ratio of the active material, annealing conditions of the active layer and the metal evaporation conditions for the cathode. All the optimization procedures were carried out in controlled atmosphere to minimize the environmental effect inference during fabrication of the solar cell devices. All the characterization was carried out at ambient conditions. The efficiency of the solar cell was improved from 0.009% to 6.2%. the environmental stability of the fabricated devices were carried out after encapsulating it with epoxy based resin in both ambient conditions as well as extreme conditions like 85% RH at 25°C inside the humidity chamber. It was observed that both the data matches well with each other indicating proper encapsulation required to safe guard the device for the better performance over the period of time. Second part of this work mainly deals with understanding the structure property relationship of thiophene based donor- acceptor- donor molecule 2,5-dithienyl-3,4-(1,8-naphthylene) cyclopentadienone (DTCPA), which is highly crystalline, low band gap organic molecule which absorbs over entire visible region of the solar spectra. DTCPA crystals of various morphologies were prepared by various recrystallization routes. It was observed that macro scale morphology of these crystals differs from each other. Also depending on the method of recrystallization sizes of the crystals also varies. All the recrystallized DTCPA shows strong orientation toward (001) direction. However, it was observed that lattice parameters of these crystals slightly differ from each other owing to the recrystallization methodology. These variations in crystal parameters are more than 0.02 which is significant. It was also observed that the crystallite sizes depend on the recrystallization routes. Slow evaporation of concentrated solution (SEC) grown crystals has the larger crystallite size of 170nm. It was observed that absorption range of these crystals slightly differ from each other owing to the change in the crystallite sizes and crystal parameters. Third part of this work deals with the fabrication and optimization of thermal evaporation process of DTCPA for photovoltaic applications. DTCPA is stable at higher temperatures as well as has sharp melting point which make it ideal candidate for thermal evaporation. In this work films of DTCPA were fabricated for various evaporation rates by thermal evaporation technique. Chemical integrity of the molecules upon evaporation is found to be intact as observed from FTIR spectroscopy. XRD shows that at lower (25 W/m2) as well as higher (40 W/m2) films are oriented to (001), (400) as well as (311) directions, at 30 W/m2 and 35 W/m2 there is a strong orientation towards (311) and (001) directions respectively. Photo luminescence studies indicate that there is strong 410 nm emission for films deposited at the power of 25 W/m2 and 40 W/m2. Microscopic studies confirm that morphology is dependent on the deposition rates as it changes with the change in deposition rate. This in turn reflects in the device characteristics of these films. It was observed that films deposited at high deposition rates show better device characteristics with high VOC and current density values. All these device fabrication and characterizations were carried out in ambient conditions. Fourth part of this work deals with P3HT - DTCPA composites which exhibit wide range of light absorption. It was observed that DTCPA act as nucleating centers for the P3HT molecules and increases crystallinity in the composite. Furthermore, DTCPA helps in exciton separation because of donor and acceptor moieties present in the molecule. It also helps in charge transportation because of its crystalline nature and further it induces molecular ordering in the P3HT matrix. The band diagram of P3HT- DTCPA suggests that the band edges of both materials are ideal for charge separation. In addition, crystalline nature of the DTCPA molecule helps in effective charge transportation. J-V characteristics shows that there is large built in potential in the devices from these blends leading to large Voc. Composites with lower DTCPA loadings show higher efficiency than with higher loadings. These devices were prepared in ambient conditions and needs to be optimized for obtaining better device properties. In the fifth part of the work two types of system were studied to understand the band edge matching on the photovoltaic properties, carbazole based copolymers and DTCPA based copolymers. In the case of carbazole based copolymers it was observed that by copolymerizing carbazole with thiophene based derivatives lowers the band gap and modifies the HOMO and LUMO levels for better suit for the photovoltaic device fabrication. It was observed that that is two orders of improvements in the efficiency by co polymerizing carbazole with benzothiodizole as improves the JSC and VOC. Also the copolymerization of carbazole with both benzothiodiazole and bithiophene results in better light harvesting as the optical band gap was lowered. In the case of DTCPA copolymers with DTBT and DHTBT as both are random copolymers the solubility was low as well as their HOMO band edge was mismatched with the PEDOT: PSS which is a hole transport layer. However, the alternate polymerization of DTCPA with DTBT improved the band edge matching and also the solubility. As a result there was tenfold improvement in the charge collection and hence the efficiency was improved from 0.02% to 2.4%. Many of the conducting polymers have good material property but poor filmability. In the sixth part of this work deals with fabrication of device quality films by alternate deposition technique like pulsed laser deposition. Two types of system were studied in this work (i) polypyrrole- MWCNT nanocomposites and (ii) Poly DTCPA polymer. In both the cases it was observed that chemical integrity of the polymer retained during ablation. PolyDTCPA films were fabricated by pulsed laser deposition by both IR (Nd-YAG) and UV (KrF) laser source. Morphological studies indicate that IR laser ablated films were particulate in nature whereas UV laser ablated films were grown as continuous layers as polyDTCPA absorbs better in UV region. As a result the IV characteristics indicate that IR laser ablated films are resistive in nature and UV laser ablated films are good rectifiers indicating the suitability of the process for fabrication of device quality films.

Cette thèse est consacrée à l’étude de la stabilisation directe et indirecte de différents systèmes d’équations d’ondes avec un contrôle frontière de type fractionnaire ou un contrôle local viscoélastique de type Kelvin-Voight. Nous considérons, d’abord, la stabilisation de l’équation d’ondes multidimensionnel avec un contrôle frontière fractionnaire au sens de Caputo. Sous des conditions géométriques optimales, nous établissons un taux de décroissance polynomial de l’énergie de système. Ensuite, nous nous intéressons à l’étude de la stabilisation d’un système de deux équations d’ondes couplées via les termes de vitesses, dont une seulement est amortie avec contrôle frontière de type fractionnaire au sens de Caputo. Nous montrons différents résultats de stabilités dans le cas 1-d et N-d. Finalement, nous étudions la stabilité d’un système de deux équations d’ondes couplées avec un seul amortissement viscoélastique localement distribué de type Kelvin-Voight. / This thesis is devoted to study the stabilization of the system of waves equations with one boundary fractional damping acting on apart of the boundary of the domain and the stabilization of a system of waves equations with locally viscoelastic damping of Kelvin-Voight type. First, we study the stability of the multidimensional wave equation with boundary fractional damping acting on a part of the boundary of the domain. Second, we study the stability of the system of coupled onedimensional wave equation with one fractional damping acting on a part of the boundary of the domain. Next, we study the stability of the system of coupled multi-dimensional wave equation with one fractional damping acting on a part of the boundary of the domain. Finally, we study the stability of the multidimensional waves equations with locally viscoelastic damping of Kelvin-Voight is applied for one equation around the boundary of the domain.

Le but de cette thèse est de définir une méthode d'optimisation de formes qui conjugue l'utilisation de la dérivée seconde de forme et la méthode des lignes de niveaux pour la représentation d'une forme.On considèrera d'abord deux cas plus simples : un cas d'optimisation paramétrique et un cas d'optimisation discrète.Ce travail est divisé en quatre parties.La première contient le matériel nécessaire à la compréhension de l'ensemble de la thèse.Le premier chapitre rappelle des résultats généraux d'optimisation, et notamment le fait que les méthodes d'ordre deux ont une convergence quadratique sous certaines hypothèses.Le deuxième chapitre répertorie différentes modélisations pour l'optimisation de formes, et le troisième se concentre sur l'optimisation paramétrique puis l'optimisation géométrique.Les quatrième et cinquième chapitres introduisent respectivement la méthode des lignes de niveaux (level-set) et la méthode des éléments-finis.La deuxième partie commence par les chapitres 6 et 7 qui détaillent des calculs de dérivée seconde dans le cas de l'optimisation paramétrique puis géométrique.Ces chapitres précisent aussi la structure et certaines propriétés de la dérivée seconde de forme.Le huitième chapitre traite du cas de l'optimisation discrète.Dans le neuvième chapitre on introduit différentes méthodes pour un calcul approché de la dérivée seconde, puis on définit un algorithme de second ordre dans un cadre général.Cela donne la possibilité de faire quelques premières simulations numériques dans le cas de l'optimisation paramétrique (Chapitre 6) et dans le cas de l'optimisation discrète (Chapitre 7).La troisième partie est consacrée à l'optimisation géométrique.Le dixième chapitre définit une nouvelle notion de dérivée de forme qui prend en compte le fait que l'évolution des formes par la méthode des lignes de niveaux, grâce à la résolution d'une équation eikonale, se fait toujours selon la normale.Cela permet de définir aussi une méthode d'ordre deux pour l'optimisation.Le onzième chapitre détaille l'approximation d'intégrales de surface et le douzième chapitre est consacré à des exemples numériques.La dernière partie concerne l'analyse numérique d'algorithmes d'optimisation de formes par la méthode des lignes de niveaux.Le Chapitre 13 détaille la version discrète d'un algorithme d'optimisation de formes.Le Chapitre 14 analyse les schémas numériques relatifs à la méthodes des lignes de niveaux.Enfin le dernier chapitre fait l'analyse numérique complète d'un exemple d'optimisation de formes en dimension un, avec une étude des vitesses de convergence / The main purpose of this thesis is the definition of a shape optimization method which combines second-order differentiationwith the representation of a shape by a level-set function. A second-order method is first designed for simple shape optimization problems : a thickness parametrization and a discrete optimization problem. This work is divided in four parts.The first one is bibliographical and contains different necessary backgrounds for the rest of the work. Chapter 1 presents the classical results for general optimization and notably the quadratic rate of convergence of second-order methods in well-suited cases. Chapter 2 is a review of the different modelings for shape optimization while Chapter 3 details two particular modelings : the thickness parametrization and the geometric modeling. The level-set method is presented in Chapter 4 and Chapter 5 recalls the basics of the finite element method.The second part opens with Chapter 6 and Chapter 7 which detail the calculation of second-order derivatives for the thickness parametrization and the geometric shape modeling. These chapters also focus on the particular structures of the second-order derivative. Then Chapter 8 is concerned with the computation of discrete derivatives for shape optimization. Finally Chapter 9 deals with different methods for approximating a second-order derivative and the definition of a second-order algorithm in a general modeling. It is also the occasion to make a few numerical experiments for the thickness (defined in Chapter 6) and the discrete (defined in Chapter 8) modelings.Then, the third part is devoted to the geometric modeling for shape optimization. It starts with the definition of a new framework for shape differentiation in Chapter 10 and a resulting second-order method. This new framework for shape derivatives deals with normal evolutions of a shape given by an eikonal equation like in the level-set method. Chapter 11 is dedicated to the numerical computation of shape derivatives and Chapter 12 contains different numerical experiments.Finally the last part of this work is about the numerical analysis of shape optimization algorithms based on the level-set method. Chapter 13 is concerned with a complete discretization of a shape optimization algorithm. Chapter 14 then analyses the numerical schemes for the level-set method, and the numerical error they may introduce. Finally Chapter 15 details completely a one-dimensional shape optimization example, with an error analysis on the rates of convergence

We study cellular automata as discrete dynamical systems and in particular investigate under which conditions two cellular automata are topologically conjugate. Based on work of McKinsey, Tarski, Pierce and Head we introduce derivative algebras to study the topological structure of sofic shifts in dimension one. This allows us to classify periodic cellular automata on sofic shifts up to topological conjugacy based on the structure of their periodic points. We also get new conjugacy invariants in the general case. Based on a construction by Hanf and Halmos, we construct a pair of non-homeomorphic subshifts whose disjoint sums with themselves are homeomorphic. From this we can construct two cellular automata on homeomorphic state spaces for which all points have minimal period two, which are, however, not topologically conjugate. We apply our methods to classify the 256 elementary cellular automata with radius one over the binary alphabet up to topological conjugacy. By means of linear algebra over the field with two elements and identities between Fibonacci-polynomials we show that every conjugacy between rule 90 and rule 150 cannot have only a finite number of local rules. Finally, we look at the sequences of finite dynamical systems obtained by restricting cellular automata to spatially periodic points. If these sequences are termwise conjugate, we call the cellular automata conjugate on all tori. We then study the invariants under this notion of isomorphism. By means of an appropriately defined entropy, we can show that surjectivity is such an invariant.

This diploma thesis deals with the legal regulation of derivatives contracts with respect to their economic nature. It provides a detailed view on the legislation regulating derivatives contracts in the legal order of the Czech Republic. Considering the interconnection of local derivatives markets, this diploma thesis pays attention to the legal regulation and standardization of derivatives contracts in foreign countries and at the international level. The first part of this thesis describes basic features of derivatives and proposes their typology. The aim of the following part is to evaluate the contemporary legal regulation of derivatives contracts in the Czech Republic. The rest of this thesis elaborates on foreign and international legal regulation of derivatives contracts. The main goal of this diploma thesis is to evaluate present the state of the regulation of derivatives contracts in the Czech Republic, asses to what degree it reflects their economic nature, and eventually, propose legal changes.

Na produção do etanol a etapa mais importante e crítica é a fermentação, por isso, há necessidade de focar a atenção ao processo e contaminações. Os contaminantes bacterianos de maior presença nessa etapa são os Lactobacillus. Com essa preocupação os objetivos deste trabalho são mostrar alternativas a redução desses contaminantes sendo eles no caldo ou no fermento (leveduras). Para isso amostras de caldo de cana-de-açúcar contaminados in vitro, individualmente, com sete diferentes espécies de Lactobacillus foram submetidas ao tratamento térmico visando confirmar a sensibilidade das mesmas à temperatura da água em ebulição. Amostras do caldo de cana-de-açúcar foram colocadas em uma cuba de clarificação com a água em ebulição. Foram retiradas amostras em diferentes tempos (0, 2, 3, 4 e 5 minutos) para que realizasse contagens (UFC/mL). Como já era esperado, as bactérias em questão se mostraram sensíveis à altas temperaturas não sobrevivendo por mais de 4 minutos. E com isso levantou-se a hipótese destas estarem presentes em dornas de fermentação devido à falhas de processamento (como uma clarificação ineficiente) e recontaminações posteriores. O projeto teve como objetivo também buscar uma alternativa ao tratamento ácido (ácido sulfúrico), utilizado como forma de descontaminação das leveduras (fermento). Foram utilizadas diferentes soluções alcoólicas (15, 20, 25, 30 e 35 % v/v) e em diferentes pH (2,5 e 6,0). Estas foram contaminadas, individualmente, com as mesmas sete diferentes espécies de Lactobacillus para verificação de sua sensibilidade ao etanol. Nos tempos (0, 30, 60, 90 e 120 minutos) foram retiradas amostras para contagens (UFC/mL). Os Lactobacillus se mostraram sensíveis ao etanol sendo mais evidente a concentrações maiores que 20% v/v. / In the ethanol production the most important and critical stage is the fermentation, therefore the necessity of focusing the attention to the process and contaminations. The contaminants of bigger presence in this stage are the Lactobacillus. With this concern the purpose of this work are shown alternatives to these contaminants. For that, samples of sugar cane broth contaminated in vitro, with seven different Lactobacillus species were subjected to the thermal treatment aiming to confirm the sensitivity of them at temperature of boiling water. Samples of sugar cane broth were placed in clarification vat with boiling water and were withdrawn in different times (0, 2, 3, 4 and 5 minutes) so that it carried out counting (UFC/mL), checking the sensitivity of microorganisms to temperature. As was expected, the bacteria in question were sensitive not survive for more than 4 minutes. And with that raised the possibility of they were present in fermentation tanks due to the failure of processing (like an inefficient clarification) and subsequent recontamination. The purpose of the project is also find an alternative to acid treatment (sulphuric acid), used as decontamination form of the yeast (leaven). Were used different alcoholic solutions (15, 20, 25, 30 and 35 % v/v) and in different pH (2,5 and 6,0). These were contaminated (separately) in laboratory with the same seven different lactobacillus genus for checking their sensitivity to ethanol. At times (0, 30, 60, 90 and 120 minutes) samples were withdrawn for counts (UFC / mL). The Lactobacillus were sensitive to ethanol, being more evident at 20% v / v.

<p>У&nbsp; докторској&nbsp; дисертацији&nbsp; је&nbsp; елаборирано&nbsp; истраживање&nbsp; које&nbsp; се&nbsp; односи&nbsp; на&nbsp; примену савремених технологија у настави математике на универзитетском нивоу. Истраживање се заснива&nbsp; на&nbsp; комбиновању&nbsp; различитих&nbsp; наставних&nbsp; метода,&nbsp; са&nbsp; циљем&nbsp; унапређења&nbsp; квалитета знања&nbsp; студената&nbsp; у&nbsp; области&nbsp; реалних&nbsp; функција&nbsp; и&nbsp; њихових&nbsp; особина.&nbsp; Бројна&nbsp; ранија истраживања&nbsp; бавила&nbsp; су&nbsp; се&nbsp; применом&nbsp; методе&nbsp; колаборативног&nbsp; рада&nbsp; у&nbsp; настави,&nbsp; као&nbsp; и имплементацијом&nbsp; савремене&nbsp; технологије&nbsp; у&nbsp; наставни&nbsp; процес.&nbsp; У&nbsp; докторској&nbsp; дисертацији описане&nbsp; су&nbsp; наставне&nbsp; методе&nbsp; које&nbsp; се&nbsp; заснивају&nbsp; на&nbsp; примени&nbsp; динамичког&nbsp; софтвера&nbsp; у испитивању&nbsp; особина&nbsp; функција,&nbsp; односно&nbsp; класа&nbsp; (фамилија)&nbsp; функција,&nbsp; комбиноване&nbsp; са методама колаборативног, односно индивидуалног рада студената. Коришћењем погодног динамичког&nbsp; софтвера,&nbsp; израђени&nbsp; су&nbsp; едукативни&nbsp; материјали&nbsp; који&nbsp; се&nbsp; могу&nbsp; користити&nbsp; у<br />настави.&nbsp; Спроведена&nbsp; су&nbsp; појединачна&nbsp; истраживања,&nbsp; која&nbsp; су&nbsp; имала&nbsp; за&nbsp; циљ&nbsp; утврђивање степена утицаја примене новог методског приступа на постигнућа&nbsp; студената у посматраној области. Резултати сваког од истраживања су статистички анализирани. Дата су закључна разматрања,&nbsp; која&nbsp; садрже&nbsp; дискусију&nbsp; о&nbsp; резултатима&nbsp; спроведених&nbsp; истраживања,&nbsp; као&nbsp; и смернице&nbsp; за&nbsp; имплементацију&nbsp; новог&nbsp; методског&nbsp; приступа&nbsp; у&nbsp; наставни&nbsp; процес&nbsp; и&nbsp; евентуална даља истраживања.</p> / <p>U&nbsp; doktorskoj&nbsp; disertaciji&nbsp; je&nbsp; elaborirano&nbsp; istraživanje&nbsp; koje&nbsp; se&nbsp; odnosi&nbsp; na&nbsp; primenu savremenih tehnologija u nastavi matematike na univerzitetskom nivou. Istraživanje se zasniva&nbsp; na&nbsp; kombinovanju&nbsp; različitih&nbsp; nastavnih&nbsp; metoda,&nbsp; sa&nbsp; ciljem&nbsp; unapređenja&nbsp; kvaliteta znanja&nbsp; studenata&nbsp; u&nbsp; oblasti&nbsp; realnih&nbsp; funkcija&nbsp; i&nbsp; njihovih&nbsp; osobina.&nbsp; Brojna&nbsp; ranija istraživanja&nbsp; bavila&nbsp; su&nbsp; se&nbsp; primenom&nbsp; metode&nbsp; kolaborativnog&nbsp; rada&nbsp; u&nbsp; nastavi,&nbsp; kao&nbsp; i implementacijom&nbsp; savremene&nbsp; tehnologije&nbsp; u&nbsp; nastavni&nbsp; proces.&nbsp; U&nbsp; doktorskoj&nbsp; disertaciji opisane&nbsp; su&nbsp; nastavne&nbsp; metode&nbsp; koje&nbsp; se&nbsp; zasnivaju&nbsp; na&nbsp; primeni&nbsp; dinamičkog&nbsp; softvera&nbsp; u ispitivanju&nbsp; osobina&nbsp; funkcija,&nbsp; odnosno&nbsp; klasa&nbsp; (familija)&nbsp; funkcija,&nbsp; kombinovane&nbsp; sa metodama kolaborativnog, odnosno individualnog rada studenata. Korišćenjem pogodnog dinamičkog&nbsp; softvera,&nbsp; izrađeni&nbsp; su&nbsp; edukativni&nbsp; materijali&nbsp; koji&nbsp; se&nbsp; mogu&nbsp; koristiti&nbsp; u<br />nastavi.&nbsp; Sprovedena&nbsp; su&nbsp; pojedinačna&nbsp; istraživanja,&nbsp; koja&nbsp; su&nbsp; imala&nbsp; za&nbsp; cilj&nbsp; utvrđivanje stepena uticaja primene novog metodskog pristupa na postignuća&nbsp; studenata u posmatranoj oblasti. Rezultati svakog od istraživanja su statistički analizirani. Data su zaključna razmatranja,&nbsp; koja&nbsp; sadrže&nbsp; diskusiju&nbsp; o&nbsp; rezultatima&nbsp; sprovedenih&nbsp; istraživanja,&nbsp; kao&nbsp; i smernice&nbsp; za&nbsp; implementaciju&nbsp; novog&nbsp; metodskog&nbsp; pristupa&nbsp; u&nbsp; nastavni&nbsp; proces&nbsp; i&nbsp; eventualna dalja istraživanja.</p> / <p>In&nbsp; the&nbsp; doctoral thesis,&nbsp; a&nbsp; research&nbsp; on&nbsp; the&nbsp; application&nbsp; of&nbsp; modern&nbsp; technologies&nbsp; in&nbsp; teaching mathematics at the university level is elaborated. The research is based on the combination of different teaching methods, with the aim of improving the quality of&nbsp; students&#39; knowledge of real functions and their properties. Numerous previous research was carried out using the method of collaborative teaching work in teaching,&nbsp; as well as the implementation of modern technology in the&nbsp; teaching&nbsp; process.&nbsp; In&nbsp; the&nbsp; doctoral thesis,&nbsp; teaching&nbsp; methods&nbsp; are&nbsp; described&nbsp; based&nbsp; on&nbsp; the application of dynamic software in the examination of the properties of functions, i.e. classes (families) of functions, combined with methods of collaborative, or individual work of students.By&nbsp; using&nbsp; suitable&nbsp; dynamic&nbsp; software, educational&nbsp; materials&nbsp; that&nbsp; can&nbsp; be&nbsp; used&nbsp; in&nbsp; teaching&nbsp; are created. Individual research was conducted, aimed at determining the degree of impact of the application&nbsp; of&nbsp; a&nbsp; new didactic approach&nbsp; on&nbsp; students&#39;&nbsp; achievements&nbsp; in&nbsp; the&nbsp; observed&nbsp; field. The results of each study were statistically analyzed. Final conclusions are provided, which contain a discussion of the results of the conducted research, as well as guidelines for the implementation of the new didactic approach in the teaching process and possible further research.</p>

Plusieurs initiatives d’origines européenne et nationale ont contribué à l’émergence d’un nouveau concept en droit d’auteur : l’œuvre transformatrice. La récurrence et la persistance des débats en la matière prouvent que ce concept ne traduit pas qu’un phénomène conjoncturel. Ces raisons conduisent en conséquence à lui consacrer une étude afin de déterminer la pertinence de l’admission de ce concept en droit d’auteur. L’étude débute par le constat que certains auteurs travaillent en s’adossant volontairement à une ou plusieurs œuvres originelles créées par autrui, qu’ils intègrent à leur processus créatif, aboutissant ainsi à la création d'une œuvre nouvelle. Ces pratiques d’emprunt créatif à l’œuvre d’autrui ont désormais pris une dimension particulière. Celle-ci s’explique d’une part par le développement du numérique. D’autre part, une partie du public, soit les destinataires des œuvres, souhaite participer activement à la création et revendique le droit d’utiliser les œuvres d’autrui comme autant de moyens d’expression et de création. Le législateur a certes envisagé l’hypothèse dans laquelle une œuvre nouvelle procède d'une œuvre préexistante au travers de la catégorie légale des œuvres composites. Cependant, les dispositions éparses qui lui sont consacrées souffrent d’une terminologie et d’un régime imprécis qui n’ont jamais fait l’objet d’une étude juridique approfondie. L’émergence du concept d’œuvre transformatrice illustre l’importance théorique et pratique de remettre en cause cette catégorie légale des œuvres composites. Aussi, la délimitation du concept suppose, dans un premier temps, une nécessaire remise en cause des catégories traditionnelles qui constituent les piliers du droit d'auteur, ainsi que les impératifs auxquels la constitution de ce monopole doit répondre. Cette lecture renouvelée aboutit à circonscrire la notion fonctionnelle d’œuvre transformatrice. Loin de se cantonner à proposer une nouvelle version de l’œuvre originelle, l’auteur de l’œuvre transformatrice exprime une opinion sur l’œuvre d’autrui, en induisant un décalage avec celle-ci. Bien souvent, il a réalisé son œuvre sans l’autorisation de l’auteur de l’œuvre originelle, et leurs droits entrent alors en conflit. Dans un second temps, l’étude s’attelle à appréhender ce conflit de droits. Le droit positif s’avère limité, de sorte qu’il faut affiner l’analyse juridique du lien unissant ces deux auteurs en l’enrichissant de la comparaison avec des mécanismes extérieurs au droit d’auteur, et d’autres issus du droit comparé. En définitive, c’est par le mécanisme de l’exception au droit d’auteur que l’on trouvera le moyen de concilier de manière pérenne les droits de l’auteur originel et ceux de l’auteur de l’œuvre transformatrice. / Transformative work is a new concept in copyright law that is emerging from several recent initiatives across Europe. The recurring debate on this concept indicates that it is not short-lived and highlights the need for a strategy to define a suitable legal framework. The purpose of this study is to assess the relevance of including the concept of transformative works in French and European Union copyright law. The starting point is authors’ integration of original works created by third parties in their creative process so as to generate new pieces of work. These practices are increasing in occurrence, with the rise of the digital age being one explanation of their prevalence. Furthermore, the public appreciates the value of these works and wishes to maintain the right to use third party works as a means of creative expression. The legislator has envisaged categorising new work inspired from pre-existing work as derivative and composite work. Nevertheless, the scarce arrangements that have been developed lack a proper framework and a detailed legal study has yet to be undertaken. The emergence of the concept of transformative work highlights the practical and theoretical need to challenge the legal definition of derivative and composite work. Far from offering a new derived version of the original piece of work, the author of a transformative work expresses an opinion on the third party work, by inserting a differentiating element. Therefore, the format of expression and content justify the legal analysis between the author of the original piece of work and the author of the transformative work. As such, framing the concept involves in the first instance, questioning the traditional pillars of copyright law and their requirements. This new understudy leads to the framing of the definition of transformative work. Secondly, this study focusses on how several copyright laws can co-exist. The content of positive law is limited and therefore, the study helps develop the concept of transformative work by comparing external mechanisms of both copyright and comparative law.In conclusion, incorporating transformative work into copyright law is based on the exception mechanism of copyright law.

In this thesis we apply neural networks as nonparametric and nonlinear methods to the Central European stock markets returns (Czech, Polish, Hungarian and German) modelling. In the first two chapters we define prediction task and link the classical econometric analysis to neural networks. We also present optimization methods which will be used in the tests, conjugate gradient, Levenberg-Marquardt, and evolutionary search method. Further on, we present statistical methods for comparing the predictive accuracy of the non-nested models, as well as economic significance measures. In the empirical tests we first show the power of neural networks on Mackey-Glass chaotic time series followed by real-world data of the daily and weekly returns of mentioned stock exchanges for the 2000:2006 period. We find neural networks to have significantly lower prediction error than classical models for daily DAX series, weekly PX50 and BUX series. The lags of time-series were used, and also cross-country predictability has been tested, but the results were not significantly different. We also achieved economic significance of predictions with both daily and weekly PX-50, BUX and DAX with 60% accuracy of prediction. Finally we use neural network to learn Black-Scholes model and compared the pricing errors of...