Abstract Deinococcus radiodurans is highly resistant to radiation when it grown in tryptone-glucose-yeast extraxt (TGY) medium. It oxidized glucose slowly mainly by the pentose phosphate pathway (PPP) and showed little glycolytic Embden-Meyerhof pathway (EMP) activity. The addition of 10 µM Mn(II) into the stationary phase cultures, could induced new round of cell division (Mn-CD effect) and the EMP activity. Glucose metabolized by Mn-CD cells at a EMP:PPP=6:1 ratio. In analyzing the metabolites for DNA repair, we found that after the addition of Mn(II) , the concentrations of PPP metabolites such as insione monophosphate (IMP)¡Buridine monophosphate (UMP) and NAD (nicotine adenine dinucleotide) were greatly reduced. This event is also occurred when replacing the glucose by fructose, sodium acetate, or removing glucose from the TGY culture medium. Besides, we also found that the TGY and TFY grown cells contained more PPP metabolites than those of TAY and TY cells. This finding suggested that glucose and fructose were metabolized by the PPP pathway in D. radiodurans. Finally, the concentrations of IMP¡BUMP and NAD in the cells were greatly decreased after UV irradiation. This indicated that these metabolites were probably employed to repair the DNA damage causing by UV irradiation.

Induction machines are the most widely used type of electrical machines because of their robustness, simplicity, and relatively low cost. However, the small airgap in the induction machine makes them more susceptible to Unbalanced Magnetic Pull (UMP). This is because the magnitude of the UMP is a function of the degree of eccentricity, which is the ratio between the length of misalignment and the mean airgap length. The bearing-related failure accounts for approximately 41% of the total failures of induction machines; the percentages of bearing-related failure would be higher for applications in a harsher environment. In this thesis, the UMP caused by rotor eccentricity is investigated, because a small degree of rotor eccentricity is unavoidable due to the manufacturing tolerance and 80% of the mechanical faults could cause rotor eccentricity in electrical machines. When the rotor is not at the centre of the stator, the eccentric rotor causes an uneven airgap around the rotor, in which the magnetic permeance with the higher harmonics content will be created. The magnetomotive force (MMF) produces additional pole-pair ±1 magnetic flux around the airgap. The interaction between each magnetic flux with its pole pair ±1 magnetic flux produces UMP. As only the magnetic flux that crosses the airgap causes UMP, the magnetic flux is categorised into magnetising flux and airgap leakage flux, because both types of flux possess different characteristics at a different rotor slip. As the airgap leakage flux is difficult to calculate analytically, an empirical method is proposed to estimate the UMP caused by the airgap leakage flux. Then, the UMP caused by the magnetising flux can also be estimated by using the empirical method. The parameters for the empirical method can be found by using either the FEA or the experimental results. The damping effect of the magnetising flux in a parallel connected rotor bar is discussed and a damping coefficient is introduced to explain this scenario. The damping coefficient can also be used to calculate the UMP in a steady state analysis. UMP comparisons between the cage rotor and wound rotor induction machines are made. The wound rotor has a much higher UMP because the pole-specific wound rotor could not damp the additional pole pair ±1 magnetic flux. Therefore, a damper winding at the stator slot is also proposed in order to damp the UMP by producing a counteracting flux. In addition, analytical equations have also been derived for different scenarios, such as static eccentricity, dynamic eccentricity, axial-varying eccentricity, and skew rotor bars. Finite Element Analysis (FEA) and experimental work are used to demonstrate the derived analytical equation. Furthermore, the power losses caused by the rotor eccentricity are investigated. Iron losses, copper losses, and frictional loss are discussed and compared with both the analytical equation and the FEA results. In order to reduce the UMP in the induction machines, the two proposed methods are the slip control method and damper windings topology. The slip control method utilises the non-linearity characteristic of the UMP at different rotor slip. To find the optimum operating slip with the lowest UMP, the UMP/Torque ratio is introduced. The characteristics of the UMP/Torque ratio varies with the type and design of the induction machines. However, this method is only applicable when the machine is lightly loaded, because the magnetising flux is limited by the capped terminal voltage and the core saturation of the machine. For the damper winding topology, a circulating current flowing in the damper winding could produce a counteracting flux to damp the UMP. The proposed damper windings configuration is only suitable for the induction machine with an even pole pair number. Finally, comparisons between both UMP reduction methods are made.

Comment un parti de gouvernement, comme l’UMP, qui se revendique comme moderne, professionnalisé et désidéologisé, parvient-il à mobiliser à grande échelle ? Au croisement d’une sociologie des partis et des mobilisations politiques, cette thèse est dédiée à l’étude de la genèse et des effets de la campagne de recrutement menée par la direction sarkozyste de l’UMP de 2004 à 2008, qui a fait usage d’une rhétorique modernisatrice et de pratiques managériales. Elle montre que la « modernisation managériale », en tant qu’idéologie institutionnelle, a constitué un ressort essentiel de cette mobilisation. Ce résultat ne peut se comprendre indépendamment de la sociographie des « nouveaux adhérents », qui, comparés aux membres de formations fondatrices de l’UMP appartiennent davantage aux milieux entrepreneuriaux. L’engagement de ces nouveaux entrants à l’identité et aux attentes distinctes a suscité une résistance infrapolitique de la part des anciens et a eu des effets paradoxaux sur l’institution (conflictualisation des relations internes, réactivation des identités gaullistes et libérales et idéologisation des membres). Au niveau théorique, ce travail plaide pour l’usage d’une approche culturelle des institutions partisanes qui apparaît paradoxalement la plus à même de rendre compte des logiques qui conduisent certains partis de gouvernement à apparaître de plus en plus comme des entreprises rationnelles. / How does a party of government, such as the UMP, which defines itself as modern, professionalized and without ideology, achieve to mobilize widely? At the intersection of a sociology of parties and political mobilization, this study is dedicated to the analysis of the genesis and the effects of the campaign of recruitment which was introduced by Sarkozy’s direction at the UMP from 2004 to 2008 and used a rhetoric of modernity and managerial tools. It shows that the “managerial modernization”, as an institutional ideology, was an essential condition for this mobilization. This result cannot be understood independently to a sociography of the “new” members, who, compared to the members of the former right parties, belong to entrepreneurial groups. The commitment of these new members, whose identity and expectation differ from the members of former parties, caused an infrapolitical resistance of these ones and had paradoxical effects on the institution (an increase of internal tensions, a reactivation of the gaullist and liberal identity and a renewal of member’s ideology). At a theoretical level, this study pleads for a cultural approach of partisan institutions which is paradoxically able to explain the logics that lead parties of government to appear as rational enterprises. Keywords: political parties, mobilization, UMP, commitment, activism, organizational modernization, management, ideology, culture, identity.

Wind energy has been the fastest emerging renewable energy source over the last decade. The overriding provisos to minimise greenhouse emissions and increasing concerns regarding energy security have been the major inducements for many countries to make a resolute transition to new and non-conventional power sources. Direct-drive systems for wind turbines are potentially a more reliable alternative to gearbox driven systems. Gearboxes are liable to significant accumulated fatigue torque loading with relatively high maintenance costs. It is with this in mind that the primary focus of this research is on direct-drive wind turbines. Generators in direct-drive wind turbines tend to be of large diameter and heavier due to the support structure required to maintain as small air-gap as possible between the stationary and rotating parts of the generator. Permanent magnet generators (PMGs) are the most common type to be used within direct-drive wind turbines nowadays. Generators and other drive-train components in wind turbines experience significant varying loads, which may lead to a bearing failure. These varying loads can lead to misalignment within the drivetrain producing eccentricity between the generator rotor and stator. Rotor eccentricity generates a magnetic force referred to as Unbalanced Magnetic Pull (UMP). The induced UMP for the same rotor eccentricity is much higher in PMGs than induction generators because of the higher permanent magnet magnetic field. UMP is an important issue requiring further research. A part of this study provides a more detailed treatment of UMP under varying rotor eccentricity regimes for various permanent magnet machine topologies. The effect of UMP in direct-drive PMGs on the lifetime of the main bearing is a topic that requires more research aimed at proposing design improvements and solutions. The hope being that the availability of such solutions can be applied to practical reductions in operating costs. In brief, identification of the root causes of failure and impacts on component lifetime remain a subject of research. Establishing analytical tools for studying the impact of UMP on component lifetime in direct drive wind turbines and identifying the prospects for air gap winding machines using single bearing configuration are the two key areas for further research. Firstly, this research aims to establish the relationship between bearing forces and different types of eccentricities and UMP in direct drive machines. It is intended to use such models for predicting bearing wear and fatigue. Secondly, this research aims to establish the analytical tools for studying static, dynamic and tilting eccentricity in air-gap winding direct drive generators. Such tools are used to increase the understanding of the dynamics of direct drive PM generators. The final step of this study is using a multi-body simulation software (SIMPACK) to initiate investigations and comparison by providing assessments of electromagnetic interaction and internal drive-train loading for four possible designs for a proposed 5MW direct-drive wind turbine in response to the loads normally seen by a wind turbine. The four designs include: (a) iron-cored PM direct-drive generator supported by two main bearings, (b) airgap winding PM direct-drive generator supported by two main bearings, (c) iron-cored PM direct-drive generator supported by a single main bearing, (d) airgap winding PM direct-drive generator supported by a single main bearing. An aero-elastic simulation code (HAWC2) is used to extract the hub loads for different wind speeds corresponding to the normal operation of the wind turbine. The dynamic eccentricity and its influence on the electromagnetic interaction and consequential effects on bearing loading for all four designs is examined to determine the most optimal support structural configuration for a direct-drive system. In summary, the main aim of this thesis is studying the effect of different types of rotor eccentricities in different types of direct drive PMGs on the main bearing arrangements. The results show that static rotor eccentricity has the maximum impact compared to the other types of eccentricities. The main result of an eccentricity is the induced UMP which applies directly as an extra force on the bearings. The influence of UMP on bearing wear is studied. This influence is found to be significant in PM machines and should be considered when designing the bearing stiffness. A 20% static rotor eccentricity in a PM machine is found to induce an UMP that roughly equals third the total weight of the machine. A single bearing design for a direct-drive wind turbine is proposed and compared with a conventional two-bearing design. The results show that the Iron-cored PM direct-drive generator supported by two main bearings design and airgap winding PM direct-drive generator supported by a single main bearing design have advantages over the other two designs in this study.

This study is among the first to provide insight into the assessment of the Swedish central bank’s (Riksbank) three unconventional monetary policies (UMPs) and their influence on Swedish commercial banks. The three UMPs include forward guidance (FG), quantitative easing (QE) and negative interest rate policy (repo rate). Riksbank introduced the UMPs in order to revive inflation and support Sweden’s economic recovery. The banks’ ability to certainly forecast their operations is highly dependent on the communication availed by the Riksbank on its expected future monetary policies through FG. QE is paramount because this is when commercial banks sell government bonds to the Riksbank. Repo rate determines interest rates set by banks. Four indicators (uncertainty, government bond yields, bank interest rates, borrowing and lending) were used in this study to investigate the perception of the commercial banks on the three UMPs. There are limited studies on Swedish banks’ perception of the UMPs which leaves a research gap in this area.Previous studies indicate that dominant banks in terms of asset shares and deposits are more sensitive to monetary policy shocks. The four dominant commercial banks studied include: Nordea, Handelsbanken, Swedbank and Skandinaviska Enskilda Banken. This thesis considers the evidence of the results from previous empirical studies. Empirical material for this study was collected through semi-structured interviews from respondents by the Riksbank and the four commercial banks. A deductive approach was used to interpret the information collected.Our results presents various perceptions of the dominant commercial banks on the three UMPs in relation to the four indicators. Some commercial banks perceived the increased transparency and clarity during the increased FG to have reduced their uncertainty. Other banks perceived that FG had increased their uncertainty. They questioned the credibility of the FG since they could not predict Riksbank’s monetary policies with the FG availed. In regards to the perception of QE on uncertainty, an increased signalling channel during QE implementation had resulted in a decline of their uncertainty since they were experiencing a surplus of liquidity in the banking sector. However, they stated other factors that increased market volatility during QE. The increased market volatility during QE increased their uncertainty. The four commercial banks agreed that the demand for government bonds increased while the yields of the government bonds declined. They perceived these changes to have been influenced by QE. The commercial banks’ lending, deposit and interbank interest rates have declined systematically correlating the trend of the declining repo rate. The four banks experienced a decline in their average net interest income, an improved flow of credit through higher lending volumes and stable lending margins to households and firms. Commercial banks perceived these changes to have resulted from the declining market interest rates because of the negative repo rate.Riksbank can use this study to assess the effectiveness of its UMPs on commercial banks based on the perception of the employees from these respective banks. This study discusses implications of the findings for commercial banks and the Riksbank, as well as academics in the realm of implementations and influences of UMPs.

Hydropower research is often perceived to be an old and exhausted field of study but with ageing equipment and the need for more intermittent operation caused by an increased share of other renewable energy sources new challenges lie ahead. The main focus of this dissertation are the electromagnetic forces resulting from nonuniform air gap flux, whether it be caused by rotor eccentricity or a faulty field winding. Results are predominantly obtained from measurements on an experimental generator and numerical simulations. With the computational capacity available today it is possible to numerically analyse physical phenomena that previously could only be studied with analytical tools. Numerical models can also be expanded to encompass more than one aspect of generator operation in coupled field-circuit models without model complexity surpassing computer capability. Three studies of unbalanced magnetic pull, UMP, in synchronous salient pole generators constitute the main part of this thesis. The first is a study of how parallel stator circuits affect the unbalanced magnetic pull caused by rotor eccentricity. Depending on the relationship between the geometry of the separate circuits and the direction of the eccentricity it was found that parallel circuits could reduce the UMP substantially. Secondly, an investigation of the effect of damper winding configuration on UMP was performed. The results showed that damper winding resistivity and the distance between the damper bars in a pole determine the effectiveness of the damper winding in reducing the UMP. Simulations of a production machine indicate that the reduction can be substantial from damper windings with low resistivity. The third study analyses the consequences of field winding interturn short circuits. Apart from a resulting rotating unbalanced magnetic pull it is found that the unaffected poles with the same polarity as the affected pole experience an increase in flux density. In a fourth article a new stand still frequency response, SSFR, test method including measurements of damper winding voltage and current is presented. It is found that the identified models are capable of predicting the stator to damper transfer function both with and without the damper winding measurements included.

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Submitted by Paulo Gustavo Grahl (pgrahl@fgvmail.br) on 2013-10-18T05:32:44Z No. of bitstreams: 1 DoutoradoPG_final.pdf: 23501670 bytes, checksum: 55b15051b9acc69ac74e639efe776fae (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2013-10-28T18:22:53Z (GMT) No. of bitstreams: 1 DoutoradoPG_final.pdf: 23501670 bytes, checksum: 55b15051b9acc69ac74e639efe776fae (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2013-10-29T18:24:15Z (GMT) No. of bitstreams: 1 DoutoradoPG_final.pdf: 23501670 bytes, checksum: 55b15051b9acc69ac74e639efe776fae (MD5) / Made available in DSpace on 2013-10-29T18:25:35Z (GMT). No. of bitstreams: 1 DoutoradoPG_final.pdf: 23501670 bytes, checksum: 55b15051b9acc69ac74e639efe776fae (MD5) Previous issue date: 2012-12-22 / Esta dissertação concentra-se nos processos estocásticos espaciais definidos em um reticulado, os chamados modelos do tipo Cliff & Ord. Minha contribuição nesta tese consiste em utilizar aproximações de Edgeworth e saddlepoint para investigar as propriedades em amostras finitas do teste para detectar a presença de dependência espacial em modelos SAR (autoregressivo espacial), e propor uma nova classe de modelos econométricos espaciais na qual os parâmetros que afetam a estrutura da média são distintos dos parâmetros presentes na estrutura da variância do processo. Isto permite uma interpretação mais clara dos parâmetros do modelo, além de generalizar uma proposta de taxonomia feita por Anselin (2003). Eu proponho um estimador para os parâmetros do modelo e derivo a distribuição assintótica do estimador. O modelo sugerido na dissertação fornece uma interpretação interessante ao modelo SARAR, bastante comum na literatura. A investigação das propriedades em amostras finitas dos testes expande com relação a literatura permitindo que a matriz de vizinhança do processo espacial seja uma função não-linear do parâmetro de dependência espacial. A utilização de aproximações ao invés de simulações (mais comum na literatura), permite uma maneira fácil de comparar as propriedades dos testes com diferentes matrizes de vizinhança e corrigir o tamanho ao comparar a potência dos testes. Eu obtenho teste invariante ótimo que é também localmente uniformemente mais potente (LUMPI). Construo o envelope de potência para o teste LUMPI e mostro que ele é virtualmente UMP, pois a potência do teste está muito próxima ao envelope (considerando as estruturas espaciais definidas na dissertação). Eu sugiro um procedimento prático para construir um teste que tem boa potência em uma gama de situações onde talvez o teste LUMPI não tenha boas propriedades. Eu concluo que a potência do teste aumenta com o tamanho da amostra e com o parâmetro de dependência espacial (o que está de acordo com a literatura). Entretanto, disputo a visão consensual que a potência do teste diminui a medida que a matriz de vizinhança fica mais densa. Isto reflete um erro de medida comum na literatura, pois a distância estatística entre a hipótese nula e a alternativa varia muito com a estrutura da matriz. Fazendo a correção, concluo que a potência do teste aumenta com a distância da alternativa à nula, como esperado. / This dissertation focus on spatial stochastic process on a lattice (Cliff & Ord--type of models). My contribution consists of using Edgeworth and saddlepoint series to investigate small sample size and power properties of tests for detecting spatial dependence in spatial autoregressive (SAR) stochastic processes, and proposing a new class of spatial econometric models where the spatial dependence parameters that enter the mean structure are different from the ones in the covariance structure. This allows a clearer interpretation of models' parameters and generalizes the set of local and global models suggested by Anselin (2003) as an alternative to the traditional Cliff & Ord models. I propose an estimation procedure for the model's parameters and derive the asymptotic distribution of the parameters' estimators. The suggested model provides some insights on the structure of the commonly used mixed regressive, spatial autoregressive model with spatial autoregressive disturbances (SARAR). The study of the small sample properties of tests to detect spatial dependence expands on the existing literature by allowing the neighborhood structure to be a nonlinear function of the spatial dependence parameter. The use of series approximations instead of the often used Monte Carlo simulation allows a simple way to compare test properties across different neighborhood structures and to correct for size when comparing power. I obtain the power envelope for testing the presence of spatial dependence in the SAR process using the optimal invariant test statistic, which is also locally uniformly most powerful invariant (LUMPI). I have found that the LUMPI test is virtually UMP since its power is very close to the power envelope. I suggest a practical procedure to build a test that, while not UMP, retain good power properties in a wider range for the spatial parameter when compared to the LUMPI test. I find that power increases with sample size and with the spatial dependence parameter -- which agrees with the literature. However, I call into question the consensus view that power decreases as the spatial weight matrix becomes more densely connected. This finding in the literature reflects an error of measure because the hypothesis being compared are at very different statistical distance from the null. After adjusting for this, the power is larger for alternative hypothesis further away from the null -- as one would expect.