The main task of this work is to provide a contribution to help a more deep understanding on the operation of the asymmetrical twophase induction motor with return for applications in places where a possibility of a two-phase network feeding exists. important contributions where obtained with the help of a time domain dynamic model for symmetrical and asymmetrical two-phase machines developed as part of this work. With such contributions it was possible to show that a threephase induction motor can work as a two-phase asymmetrical induction motor with return through a phase or neutral conductor, without the need of some starting devices, such as, centrifugal switch and capacitors. this was proved through load and no-load tests and by way of comparisons between theoretical and experimental results. Hence, with such a work, we are seeking for the revitalization of the asymmetrical two-phase induction motor theory, a machine that presents a non-uniform magnetomotive force and electromagnetic torque. / O objetivo principal deste trabalho é fornecer uma contribuição que ajudará no entendimento com maior profundidade sobre o funcionamento do motor de indução bifásico assimétrico com retorno para aplicações em locais onde exista a possibilidade de uma rede de alimentação bifásica. As contribuições mais importantes foram obtidas com o auxílio do modelo dinâmico no domínio do tempo para máquinas bifásicas simétricas e assimétricas desenvolvido neste trabalho. Através das contribuições obtidas foi possível mostrar que um motor de indução trifásico pode funcionar como motor de indução bifásico assimétrico com retorno pela fase ou pelo neutro, sem que o mesmo necessite de determinados componentes de partida, tais como, chave centrifuga e capacitores. isto ficou provado através dos ensaios a vazio e com carga e também por intermédio das comparações entre os resultados teóricos e experimentais. Com isto procurou-se revitalizar a teoria do motor de indução bifásico assimétrico com retorno, que possui força magnetomotriz e torque eletromagnético não uniforme. / Doutor em Ciências

Purpose: The purpose of the study is to investigate whether executives can earn abnormal return by purchasing their own stocks and establish an understanding of possible aspects. Method: In order to observe if abnormal return exists on insider buy-transactions, a method triangulation with deductive approach has been made. An event study has been adopted to measure the transaction events. In addition, CAAR has been calculated with aid of a model. These values go through a significance test in order to support the hypothesis.  Theory: The study is grounded on the efficient market hypothesis, information asymmetry, behavioural finance and signalling. Furthermore, previous research has been adopted to support the study.  Conclusion: The results of the study show that executives for growth companies can profit from abnormal returns. / Syfte: Syftet med studien är att studera om personer i ledande ställning profiterar vid insynsförvärv av aktier samt skapa en djupare förståelse kring möjliga underliggande faktorer. Metod: För att studera om det uppstår abnorm avkastning vid insynsförvärv har en metodtriangulering med deduktiv ansats behandlats. Eventstudie har använts för att mäta transaktions händelserna. Vidare beräknas CAAR med hjälp av en modell. Dessa kommer sedan att signifikanstestas för att stödja hypoteserna.  Teori: Teorier som behandlas i denna studie är den effektiva marknadshypotesen, informationsasymmetrin, beteendebaserad finansiering och signaleringshypotesen. Vidare behandlas tidigare forskningar som ger stöd till studien. Slutsats: Resultaten för studien påvisar att personer i ledande ställning för tillväxtföretag kan profitera på abnorm avkastning.

According to former brain surgeon, Nils Simonson, Swedish schools are wasting their students’ time by using teaching methods that lead to poor memorization, namely reading and listening as separate activities. He instead suggests that the students use methods that lead to better memorization. The study described in this rendering focuses on two of Simonson’s suggestions – discussion and peer teaching. This work accounts for a study, in which Swedish 8 thgrade English students were working in asymmetrical pairs, i.e. pairs composed by students on different levels of achievement. The study was aimed at finding an answer to the thesis question of whether working in asymmetrical pairs led to a larger or smaller improvement, on a final grammar test, than the improvement of the rest of the students in the class, who were working individually, and thus formed a control group for the study. The result was that the students in three out of four asymmetrical pairs improved their results more than the control group. Since one of the students in the fourth asymmetrical pair had been absent, they had only been working together during half the period of the study. This probably explains why their improvement was only on the same level as the improvement of the students in the control group. The answer to the thesis question is therefore that working in asymmetrical pairs led to better results on the final grammar test, than working individually. If the results of the participating students are divided into different groups, we also find that the students with the lowest results on the initial grammar test were those who improved their results the most, which could possibly be explained by a better room for improvement. Due to the short time range of the study, it was limited to one class, and the generalizability of the study is hence very low. However, it could potentially serve as a pilot study for larger research projects. My main idea of future research is thus to expand the study to a larger number of students. It would also be interesting to incorporate students on all levels of achievement into a similar research project. This work incorporates predominant teaching science theory, such as socio-cultural theories, and influential second language acquisition theory, such as the input hypothesis, the output hypothesis and focus on form instruction.

Les origines de la zone Franc remontent à l’époque coloniale. Imposée à sa création par la France, cette zone monétaire, au contraire des autres zones historiquement comparables comme la zone sterling, survivra à la période de décolonisation. Dans son évolution, la zone Franc va même, par la suite, se muer en une zone monétaire acceptée par les pays africains membres devenus entretemps indépendants. Sa configuration géographique connaîtra aussi des changements dus aux retraits et aux adhésions qu’elle a suscités au fil du temps. Aujourd’hui, deux caractéristiques majeures au moins semblent marquer la zone Franc : tout d’abord sa longévité ensuite une fixité absolue du taux de change (depuis plus d’un demi siècle, les francs CFA ont été dévalués une seule fois !).L’objectif de la présente thèse est d’examiner si cette pérennité relative que connaît la zone Franc actuelle s’explique par l’une au moins des théories connues des zones monétaires optimales. Dans l’ensemble, il ressort au terme de ce travail qu’au-delà des effets controversés liés aux mécanismes de fonctionnement de la zone Franc, que celle-ci n’est pas une zone monétaire optimale au vu des critères appliqués. Cependant, elle peut sinon le devenir, du moins s’en rapprocher si les économies africaines membres s’engagent dans la voie des réformes structurelles et monétaires qui s’imposent dans une perspective de développement endogène. / The origin of the Franc zone goes back to the colonial period. Imposed by FRANCE at its creation, this monetary area has survived into its post colonial period unlike say, the sterling zone. In its evolution, the Franc zone has even become an accepted monetary zone to its African members who in the meantime had become independent. Its geographical configuration has also undergone changes resulting from withdrawals and applications for membership into it as time went on. Today, two major characteristics have apparently marked the Franc zone : at first, its durability followed by the absolute fixidity of its exchange rates (CFA franc was devalued only once for over half a century !). The objective of the present theses is to examine whether this relative perennity can be explained by at least one of the theories known in optimal monetary areas. Taken as a whole, it would appear at the end of this work that beyond the controversial effects related to the working mechanisms of the Franc area in view of the criteria applied. That is not to say it can not become one because the probability exists that it can approach it if the economies of African member countries undergo structural and monetary reforms which are a must within the perspective of an endogenous development.

L’objectif de cette thèse est, d’une part, de proposer une amélioration des méthodes d’estimation des cuvettes d’affaissement et des méthodes d’évaluation des dommages susceptibles de se produire sous leurs effets et de l’autre, de développer des outils basés sur ces méthodes pour étudier les affaissements et les dommages sur des cas pratiques. L’étude de l'influence de la topographie sur les cuvettes d'affaissement dans des conditions d’exploitation simplifiées grâce à des modèles numériques avec des profondeurs d'exploitation et des pentes du sol variables a permis de proposer une nouvelle fonction d’influence basée sur une densité de probabilité normale asymétrique lorsque la surface du sol est non-plane. Une modélisation simplifiée des habitations en maçonnerie sous la forme de deux modèles de structures bidimensionnels croisés, alignés avec les axes d’inertie de la structure étudiée et dans lesquels la méthode des déplacements est mise en œuvre pour calculer les efforts internes et les déformations sous l’effet de déplacements imposées des fondations. Ces modèles simplifiés dont les caractéristiques géométriques et mécaniques sont définis pour chaque type de bâtiment étudié permettent d’estimer les efforts appliqués à chaque bâtiment d’une ville exposée à un affaissement de terrain et de fournir de nouveaux critères d’évaluation des dommages prenant en compte davantage d’informations que les méthodes habituelles. Une estimation des dommages dans la ville de Joeuf sur la base des nouvelles méthodes proposées, tant pour le calcul de l’affaissement que pour l’estimation des dommages, a été réalisée / The objective of this thesis is to improve the methods of subsidence computation and building damage evaluation, and to develop some tools based on these methods to study the mining subsidence and building damage cases in Lorraine. By investigating the topography influence on subsidence under simplified mining conditions, and using numerical models with varying mining depths and ground surface angles, a new influence function method, which is based on a probability density function of a skew normal distribution, to simulate the element subsidence, was firstly developed and can be used to compute the mining subsidence caused by the excavation under non-flat surface. Then, plane framed structural models were chosen to study the mechanical behavior of 3D buildings. For each building, two plane models located in the vertical sections passing through the principle inertia axes of the building’s projective polygon were considered. Their geometry and mechanical characteristics were chosen according to the construction type and used materials of the building under consideration. Then, by using the matrix displacement method with some modifications, the internal forces and displacements for the entire structure could be computed. The achieved internal forces could then be compared to damage grade criteria to determine the extent of building damage.Finally, by using the improved methods of subsidence computation and building damage evaluation, a real case application was performed in Joeuf city (France). The subsidence was computed and applied to the defined structural models as support displacements, and then the damage extents of the buildings in Joeuf were predicted

In resonant earthed distribution systems, the capacitive current of the system is compensated by grounding via a arc suppression coil. The level of fault current is then very small and independent on the fault location which greatly complicates the rapid finding of the fault site. At this moment there is no method to be used to directly locate the site of a single-phase fault in the distribution network, new methods and solutions are being constantly sought to address the shortcomings of the existent localization methods. The diploma thesis deals with the design of a universal software tool that allows to apply a new method of locating an asymmetric fault in the distribution network. The tool is created in a MATLAB environment and utilizes the negative sequence voltage measured on the low-voltage sides of the distribution transformers and the negative sequence current measured behind the power transformer. By using the proposed tool, it is possible to read the parameters of any part of the distribution system that the user enters together with the measured values of the voltage and current into the initialization file. After the specified network parameters are loaded, a numerical model is created, which is then used for the method. In the work is described in detail the way of entering the parameters of the network into the initialization file, the method of automatic assembling of the numerical model based on the entered data and the possibility of customizing the calculation parameters. At the end of the thesis, the functionality of the proposed software tool is verified on data from simulation of the test network.

Induction machines convert more than 55% of electrical energy into various other forms in industrial and domestic environments. Improved performance, especially by reduction of losses in induction machines hence can significantly reduce consumption of electricity. Many design and control methods are adopted to make induction machines work more efficiently, however certain design compromises are inevitable, such as skewing the rotor to improve the magnetic noise and torque characteristics increase the cross current losses considerably in a cage rotor, degrading the efficiency of the motor. Crosscurrent losses are the dominating stray losses which are dependent on several factors among them are percentage skew and the contact resistance between the rotor bars and laminations. It is shown in this thesis that implementing a design change which has non-skewed asymmetrical distribution of rotor slots can serve the same purpose as skewing i.e., reduction of the magnetic noise, thereby avoiding the negative effects of skewing the rotor slots especially by reducing the cross-current losses. Two design ethodologies to introduce asymmetry in rotor slots are proposed and the key performance characteristics like torque ripple, radial air gap forces are computed both numerically and analytically. Radial forces obtained from the finite element method are coupled to the analytical tool forcalculating the magnetic noise. A spectral method to calculate and separate the radial forces into vibration modes and their respective frequencies is proposed and validated for a standard 4-pole induction motor. The influence of rotor slot number, eccentricity and skew on radial forces and magnetic noise are studied using finite element method in order to understand the vibrational and acoustic behavior of the machine, especially for identifying their sources. The validated methods on standard motors are applied for investigating the asymmetrical rotor slot machines. Radial air gap forces and magnetic noise spectra are computed for the novel dual and sinusoidal symmetrical rotors and compared with the standard symmetrical rotor. The results obtained showed reduced radial forces and magnetic noise in asymmetrical rotors, both for the eccentric and noneccentric cases. Based on the results obtained some guide lines for designing  asymmetrical rotor slots are established. Magnitudes of the harmful modes of vibration observed in the eccentric rotors, which usually occur in reality, are considerably reduced in asymmetrical rotors showing lower sound intensity levels produced by asymmetrical rotors. The noise level from mode-2 vibration in a 4-pole standard 15 kW motor running with 25% static eccentricity is decreased by about 6 dB, compared to the standard rotors. Hence improved performance can be achieved by removing skew which reduces cross current losses and by employing asymmetrical rotor slots same noise level can be maintained or can be even lowered. / QC 20110221

Problemområdet som det här examensarbetet undersöker är frekvensen av överbelastningsskador inom ishockey genom en casestudie med ishockeyklubben ’Malmö Redhawks’. Tidigare forskning har visat att det finns en samband mellan asymmetrisk effektutveckling och överbelastningsskador i andra sporter och den nuvarande studien avser att förtydliga dess roll inom ishockey. Syftet med studien är att undersöka om det finns ett samband mellan asymmetrisk effektutveckling vid tävlingsprestation och frekvensen av överbelastningsskador inom ishockey, och föreslå strategier gällande hur man kan minska skadefrekvensen genom preventivt arbete. Forskningsfrågorna som ligger till grund för studien är: ”Hur har asymmetrisk effektutveckling påverkat de överbelastningsskador som inträffat under säsongen?”; och ”Vilka fysiologiska faktorer är relevanta när man utvecklar riktlinjer för skadepreventivt arbetet med överbelastningsskador inom ishockey?”. För att undersöka syftet genomfördes en sammanställning av tillgänglig empiri från säsongens matcher genom kvantitativ metod som sedan analyserades statistiskt i SPSS genom variansanalysen ’ANOVA’. Resultaten visar att det på gruppnivå inte finns en signifikant korrelation mellan effektutveckling (F=2,554, sig.=0,11), asymmetri (F=0,003, sig.=0,96) och överbelastningsskador. Det finns inte heller någon påvisbar trend när man undersöker skadetillfällena på matchnivå, och en mer komplett förklaringsmodell behöver undersökas i framtida forskningsprojekt med större omfattning. Slutsatsen är att det inte går att använda de generella riktlinjerna för att uppskatta atleters risk för överbelastningsskador. Det finns dock underlag i den tidigare forskningen för att anta att individuella riktlinjer har en relevans vid skadepreventivt arbete inom ishockey som en atlets nuläge kan jämföras med för att belysa avvikelser. Mer forskning krävs för att fastställa vilka fysiologiska faktorer som är relevanta för ishockey och hur idrotten förhåller sig till den tidigare forskningen inom området. / There has been speculations in the scientific community that the frequency of overuse injuries in ice hockey can be attributed in part to asymmetrical power development. Research has shown a correlation between more than ten percent asymmetrical power development and increased injury frequency in several other sports. This phenomenon will be examined through a case study with the elite ice hockey team ‘Malmö Redhawks’. The purpose of this study is to examine if there is a significant correlation between the occurrence of asymmetrical differences and the frequency of overuse injuries in ice hockey, and propose strategies for injury prevention. A quantitative method was used to summarize the empirical data from the previous season, which was then analysed through an ‘ANOVA’ test of variance. The results of the study shows that there is no significant correlation between power development (F=2,554, sig.=0,11), asymmetry (F=0,003, sig.=0,96) and injury frequency at the group level. There is no clear tendencies when examining the individual games either. The conclusion is that general guidelines are rough instruments for assessing an athletes risk of overuse injury in ice hockey. There is some basis in the scientific community for assuming that individual guidelines could be effective as injury prevention, but more research is needed to determine its correlations and which physiological variables that are relevant.

La jonction tunnel magnétique (JTM) commutée par la couple de transfert de spin (STT) a été considérée comme un candidat prometteur pour la prochaine génération de mémoires non-volatiles et de circuits logiques, car elle fournit une solution pour surmonter le goulet d'étranglement de l'augmentation de puissance statique causée par la mise à l'échelle de la technologie CMOS. Cependant, sa commercialisation est limitée par la fiabilité faible, qui se détériore gravement avec la réduction de la taille du dispositif. Cette thèse porte sur l'étude de la fiabilité des circuits basés sur JTM. Tout d'abord, un modèle compact de JTM incluant les problèmes principaux de fiabilité est proposé et validé par la comparaison avec des données expérimentales. Sur la base de ce modèle précis, la fiabilité des circuits typiques est analysée et une méthodologie d'optimisation de la fiabilité est proposée. Enfin, le comportement de commutation stochastique est utilisé dans certaines nouvelles conceptions d'applications classiques. / Spin transfer torque magnetic tunnel junction (STT-MTJ) has been considered as a promising candidate for next generation of non-volatile memories and logic circuits, because it provides a perfect solution to overcome the bottleneck of increasing static power caused by CMOS technology scaling. However, its commercialization is limited by the poor reliability, which deteriorates severely with device scaling down. This thesis focuses on the reliability investigation of MTJ based non-volatile circuits. Firstly, a compact model of MTJ including main reliability issues is proposed and validated by the comparison with experimental data. Based on this accurate model, the reliability of typical circuits is analyzed and reliability optimization methodology is proposed. Finally, the stochastic switching behavior is utilized in some new designs of conventional applications.

CHARLES UNIVERSITY FACULTY OF SOCIAL SCIENCES Institute of Political Studies Department of Geopolitical Studies Master's Thesis Unconventional power of small states: a comparative case study of Lithuania and Taiwan (ROC) Abstract: The hypotheses of the leading international relations theories, especially realism, face fundamental criticism for not explaining the behavior of some small states, who lack material power but play an effective and influential role in the international arena. To fill in this oversight, the contemporary discourse of small states challenges the resource-based understandings of power and seeks new avenues to explain how some small states succeed in "punching above their weight." Most recently, Dr. Tom Long (2017) synthesized previous academic researches and proposed that the small state's power can be best understood as originating in three categories: derivative, collective, and particular-intrinsic. This thesis aims to contribute to the argument that small states can possess unconventional power to advance their influence and achieve their national interests. It uses Dr. Tom Long's three categories of unconventional power, as a basis for the comparative case study of Taiwan and Lithuania - two small states that have notoriously challenge the notion of "how a small state should...