The level structure of the even-even deformed nucleus 176Hf has been studied by means of the 174yb (a,2n) 176Hf reaction through y-ray singles, conversion electron and extensive prompt and delayed y-y coincidence measurements. The half-lives of the isomeric states a·t 1333 and 1559 keV have been measured as 9.5 and 9.8 usec, respectively. Besides the ground state rotational band, the following ten rotational bands have been established: two K=0+ bands at 1150 keV and 1293 keV, a K=2+ band at 1341.1 keV, a K=3+ band at 1577.3 keV, a K=2-octupole band at 1247.5 keV, two K=6+ bands of mixed neutron and proton character at 1333.1 keV and 1761.5 keV, a K=8- band at 1559.4 keV, a K=8- and/or 7- band at 1860.3 keV and a K=7-and/or 6- band at 1798.0 keV. The de-excitation of the high K states proceeds through either of the two isomers, and were studied by novel experimental techniques which involved pulsing the alpha beam. The intrinsic structure and decay properties of the states are understood in terms of the unified model. In some cases it has been necessary to make use of unpublished McMaster results from the single neutron and proton transfer reactions. / Thesis / Doctor of Philosophy (PhD)

This diploma thesis deals with the validation of spectral average cross-sections (SACS) of 55 Mn(n,2n)54 Mn, 90 Zr(n,2n)89 Zr, 127 I(n,2n)126 I reactions in well-defined LR-0 reactor spectrum. The measurement of SACS for selected reactions is of high interest because they are used for the practical reactor dosimetry. Various experiments for description of neutron field in reactor and detector characterization, which are necessary for validation, are described. The spectral average cross-sections are derived from Net Peak Areas of irradiated samples measured using a semiconductor high purity germanium detector. Obtained result were compared with MCNP6 calculations using ENDF/B-VII.0, ENDF/B-VII.1, JEFF-3.1, JEFF-3.2, JENDL-3.3, JENDL-4, ROSFOND-2010, CENDL-3.1 and IRDFF nuclear data libraries. Notable discrepancies were found in 90 Zr(n,2n)89 Zr and 127 I(n,2n)126 I reactions. This thesis also contains a theoretical basis for the interaction of neutrons with matter.

Dans l’histoire évolutive des végétaux, la polyploïdisation a été un phénomène récurrent qui a façonné les génomes, aurait contribué à l’avènement de grandes étapes évolutives et aurait favorisé la survie de nombreuses lignées lors de crises écologiques majeures. Le principal mécanisme d’apparition d’espèces polyploïdes est la polyploïdisation sexuelle, qui implique la formation de gamètes 2n résultant de modifications de la division méiotique. Récemment plusieurs mutants produisant des taux élevés de gamètes 2n ont été identifiés chez A. thaliana. Chez cette espèce, la perte de fonction du gène AtPS1 conduit à la mise en place de fuseaux parallèles en méiose II et celle du gène AtCYCA1;2/TAM à l’omission de la seconde division méiotique. L’objectif de cette thèse a été de déterminer des facteurs et mécanismes responsables de la formation de gamètes 2n, en utilisant le rosier comme modèle végétal. Ces travaux ont permis : (i) d’identifier un facteur abiotique, la température élevée, comme inducteur de production de forts taux de gamètes 2n, (ii) de montrer que la fenêtre de sensibilité à ce facteur est restreinte à la méiose et (iii) de révéler que ces gamètes 2n produits sont principalement issus de la mise en place de fuseaux parallèles en méiose II. Afin de déterminer les mécanismes moléculaires à l’origine de leur formation, deux gènes candidats, RhPS1 et RhCYCA1 ont été identifiés chez Rosa. L’analyse de leur expression a révélé : (i) en condition non inductible, leur forte expression dans les étamines au stade méiose et (ii) la répression rapide de leurs niveaux de transcrits en condition d’induction de gamètes 2n. La fonction méiotique du gène RhPS1 a été validée par complémentation du mutant atps1-1 d’A. thaliana et par l’obtention d’une lignée rosier transgénique p35S::ARNi-RhPS1. Compte tenu de ces résultats, l’étude de la polyploïdisation et de ses mécanismes peut désormais être replacée dans le contexte actuel de changement climatique. / In the evolutionary history of plants, polyploidization has been a recurring phenomenon that has shaped the genomes, might have contributed to the occurrence of major evolutionary step and might have facilitated the survival of many plant families during major ecological crises. The main mechanism of polyploidization is sexual polyploidization, which involves the formation of 2n gametes resulting from meiotic division changes. Recently, mutants highly producing 2n gametes have been isolated in A. thaliana. Loss of AtPS1 gene function leads to parallel spindles orientation in meiosis II and loss of AtCYCA1;2/TAM gene function leads to the omission of the second meiotic division. The aim of this PhD project was to identify factors and mechanisms responsible for the 2n gametes formation, using Rosa as a model. This work permitted to: (i) discover an abiotic factor, high temperature, that can induce a high production of 2n gametes, (ii) show that the sensitivity window to this factor is narrow and restricted to meiosis and (iii) reveal that 2n gamete production in inductive condition, results from parallel spindle orientation in meiosis II. To determine molecular mechanisms responsible for their formation, two candidate genes, RhPS1 and RhCYCA1 were identified in Rosa. Analysis of their expression revealed: (i) their high expression level in stamens at meiosis stage in non-inductive condition and (ii) the rapid repression of their transcript levels under inductive condition. Meiotic gene function of RhPS1 was validated by complementation of atps1-1 mutant and by generating a rose transgenic line p35S:: RNAi-RhPS1. According to these results, polyploidization and its mechanisms can now be replaced in the context of the current climate.

Misalignment in turbomachinery has been commonly known to produce twotimes- running-speed (2N) response. This project aimed to investigate the source of the 2N vibration response seen in misaligned vibrating machinery by simulating misalignment through a coupling. Three flexible disc-pack couplings (4-bolt, 6-bolt, and 8-bolt coupling) were modeled, and parallel and angular misalignments were simulated using a finite element program. The stiffness terms obtained from the coupling simulations had 1N, 2N, and 3N harmonic components. The 4-bolt coupling had large 1N reaction components under angular and parallel misalignment. The 6-bolt coupling model only had a 1N reaction component under angular misalignment, and both cases of parallel misalignment showed a strong 2N reaction component, larger than both the 1N and 3N components. The 8-bolt coupling model under angular misalignment produced large 1N reaction components. Under parallel misalignment, it produced 1N, 2N, and 3N components that were similar in magnitude. All the couplings behaved linearly in the range studied. A simple model predicted that the 2N frequency seen in the response is caused by the harmonic (1N) term in the stiffness. The amplitude of the 2N component in the response depends on the amplitude of the 1N term in the stiffness compared to the average value of the stiffness and the frequency ratio. The rotordynamic response of a parallel and angular misaligned system was completed in XLTRC2. When the frequency ratio was 0.5, the system response with the 4-bolt and 6-bolt coupling had a synchronous 1N component that was much larger than the 2N component. The response did not have a 2N component when the 8-bolt coupling was used but the response did have a 1.6N component that was considerably larger than the 1N component. When the frequency ratio was 2, the system response with the 4-bolt and 6-bolt coupling had a synchronous 1N component and a relatively small ½ frequency component. The response with the 8-bolt coupling had a 0.4N component that was larger than the 1N component. A 5-tilting pad journal bearing was also tested to better understand its behavior under misalignment because some experts attribute the 2N response to the nonlinear forces produced by bearings with high unit loads. The response of the 5-tilting pad bearing did not produce any 2N components while the bearing was subjected to unit loads of up to 34.5 bars.

The theory of local newforms has been studied for the group of \(PGL_n\) and recently \(PGSp_4\) and some other groups of small ranks. In this dissertation, we develop a newform theory for generic supercuspidal representations of \(SO_{2n+1}\) over non-Archimedean local fields with odd characteristic by defining a family of open compact subgroup \(K(p^m)\), \(m \geq 0\) (up to conjugacy) which are analogous to the groups \(\Gamma(p^m)\) in the classical theory of modular forms. We give lower bounds on the dimension of the fixed subspaces of \(K(p^m)\) in terms of the conductor of the generic representation, and give a conjectural description of the space of old forms. These results generalize the known cases for n = 1,2 by Casselman [4] and Roberts and Schmidt [23]. / Mathematics

Le confort acoustique des passagers à l’intérieur d’un véhicule est fonction des équipements embarqués notamment le Système de Ventilation d’Air (SVA). Un SVA est un système complexe et compact, composé de plusieurs éléments. L’interaction de l’écoulement d’air avec ces éléments est un facteur influant sur les phénomènes acoustiques générés. Le projet CEVAS (Conception d’Eléments de Ventilation d’Air Silencieux), piloté par l’équipementier Valeo, a pour ambition de développer un outil numérique d’aide à la conception des SVA. Dans le cadre de projet, un banc d’essai a été développé à l’UTC en coopération avec Valeo afin de caractériser par mesures acoustique et aéraulique les composants d’un SVA dans les mêmes conditions de fonctionnement que sur véhicule. L’instrumentation acoustique de ce banc permet la caractérisation multimodale des propriétés acoustiques passives et actives de l’élément testé. Dans un premier lieu, la composante passive, représentée par la matrice de diffusion, est mesurée par la méthode multi-sources. Par la suite, la composante active, représentative de l’interaction écoulement objet, est déduite des pressions modales rayonnées en amont et en aval. Les démarches de mesure et de post-traitement sont appliquées pour des éléments académiques et des composants industriels : diaphragme, association de deux diaphragmes, volets et associations volet et mur. / Passenger’s thermal comfort inside car cabin is mainly provided by the heating ventilation and air conditioning system (HVAC). The main part of HVAC modules is placed under the dash board. An HVAC module is a compact system composed of various elements which are subject to airflow. The interaction between airflow and these in-duct elements generates noise inside car cabin. Furthermore, the blower used to blow air inside the cabin must overcome the pressure generated by HVAC elements. Noise is created and its level is linked to flow and pressure. HVAC noise is an important issue for car makers and automotive suppliers wishing to reach passenger’s satisfaction. Furthermore, thermal-engine cars are more and more silent. Also hybrid and electric car sells are expanding around the world. HVAC noise became a main issue for automotive actors. Under CEVAS project, Valeo is aiming to develop a prediction tool to design HVAC systems providing sound quality data. Within CEVAS project the UTC is in charge of performing measurements on academic elements and industrial HVAC components : diaphragm, flaps,…

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A data centre can consist of a large group of networked servers and associated power distribution, networking, and cooling equipment, all that application consumes enormous amounts of energy as a small city, which are driving to a significant increase in energy inefficiency problems in data centre, and high operational costs. Also the massive amounts of computation power contained in these systems results in many interesting distributed systems and resource management problems. In recent years, research and technologies in electrical engineering and computer science have made fast progress in various fields. One of the most important fields is the energy consumption in data centre. In recent years the energy consumption of electronic devices in data centre, as reported by. Choa, Limb and Kimb, nearly 30000000 kWh of power in a year, may consume by a large data centre and cost its operator around £3,000,000 for electricity alone. Some of the UK sites consume more than this. In the UK data centre the total power required are amid 2-3TWh per year. Energy is the largest single component of operating costs for data centres, varying from 25-60%. Agreeing to many types of research, one of the largest losses and causes of data centre energy inefficiency power distribution is from the uninterruptible power supply (UPS). So a detailed study characterized the efficiencies of various types of UPSs under a variety of operating conditions, proposed an efficiency label for UPSs, also investigate challenges related to data centre efficiency, and how all new technologies can be used to simplify deployment, improve resource efficiency, and saving cost. Data centre energy consumption is an important and increasing concern for data centre managers and operators. Inefficient UPS systems can contribute to this concern with 15 percent or more of utility input going to electrical waste within the UPS itself. For that reason, maximizing energy efficiencies, and reduce the power consumption in a data centre has become an important issue in saving costs and reducing carbon footprint, and it is necessary to reduce the operational costs. This study attempts to answer the question of how can future UPS topology and technology improve the efficiency and reduce the cost of data centre. In order to study the impact of different UPS technologies and their operating efficiencies. A model for a medium size data centre is developed, and load schedules and worked diagrams were created to examine in detail and test the components of each of the UPS system topologies. The electrical infrastructure topology to be adopted is configured to ‘2N’ and ‘N+1’ redundancy configuration for each UPS systems technologies, where ‘N’ stands for the number of UPS modules that are required to supply power to data centre. This work done at RED engineering designs company. They are professionals for designing and construction of a new Tier III and Tier IV data centres. The aim of this work is to provide data centre managers with a clearer understanding of key factors and considerations involved in selecting the right UPS to meet present and future requirements.