Cette thèse s’inscrit dans le contexte de l’ANR ISABEAU (Innovating for Structural Adhesive Bonding Evaluation and Analysis with Ultrasounds, associant des physico-chimistes et des acousticiens) et cherche à apporter des connaissances nouvelles sur l’évaluation par ultrasons du niveau d’adhésion d’un collage structural par ondes de Lamb. La première partie porte sur l’aspect cohésif et particulièrement sur l’influence du paramètre de réticulation de réseaux époxys sur les courbes de dispersion des ondes de Lamb. La deuxième partie est consacrée à la caractérisation de niveaux d’adhésion dans une structure bicouche Aluminium Epoxy en tenant compte aussi bien des aspects cohésifs qu’adhésifs. Des échantillons à niveau d’adhésion connus et maîtrisés sont réalisés avec l’aide de physico-chimistes, où l’époxy est partiellement ou totalement réticulé, et où l’interface substrat adhésif a subit différents traitements chimiques et/ou mécaniques. Les résultats expérimentaux sont confrontés à ceux issus du modèle rhéologique de Jones résolu par éléments finis. Enfin, la troisième partie porte sur l’étude d’un assemblage tricouche Aluminium/Epoxy/Aluminium et cherche à qualifier différents niveaux d’adhésion à l’aide du modèle de Jones par ondes guidées et également par l’étude des fréquences de coupure des modes verticaux de la structure. / This thesis is in the context of the ANR ISABEAU (Innovating for Structural Adhesive Bonding Evaluation and Analysis with Ultrasounds, with the association of physico-chemists and acousticians) and seeks to bring new knowledge of the ultrasonic evaluation of the level of adhesion of structural bonding using Lamb waves. The first part focuses on the cohesive aspect, in particular on the influence of the crosslinking parameter of the polymer on the Lamb waves dispersion curves. The second part is dedicated to the evaluation of the adhesion level of a bi-layer Aluminum Epoxy taking into account the both cohesive and adhesive aspects. Samples of controlled and known adhesion levels are manufactured with the help of physico-chemists, where the crosslinking of the epoxy is partial or total, and the interface substrate-adhesive have been treated chemically and/or mechanically. The experimental results are compared to those obtained from a predictive model based on the rheological model of Jones solved by finite elements method. Finally, the third part focuses on the study of tri-layers Aluminum/Epoxy/Aluminum, looking for the qualification of different levels of adhesion with the Jones model using guided waves as well as the cut-off frequencies of the structure.

Les transducteurs ultrasonores font l'objet de nombreux développements en contrôle non-destructif (CND) industriel. Utilisé ponctuellement et périodiquement, le CND ultrasonore permet d'établir des diagnostics sur la santé des matériaux. La caractérisation ultrasonore en temps réel constitue un outil de surveillance de l'évolution des propriétés physiques lors de la fabrication des matériaux composites. Dans ce contexte, des études sont menées au LOMC pour optimiser le procédé de fabrication des matériaux composites par RTM (Resin Transfer Molding) afin d’améliorer la qualité du produit. Ce travail de thèse consiste à développer des méthodes ultrasonores pour le suivi des propriétés viscoélastiques d’un composite pendant la phase de production. Les propriétés viscoélastiques sont étudiées à l’aide de modèles théoriques, de simulations numériques et de résultats expérimentaux. Des études de calibration ont été menées afin d’étudier les facteurs d’influence sur le suivi de propriétés ultrasonores lors de la mise en oeuvre d’un procédé RTM. Le suivi des paramètres viscoélastiques de résines époxy est effectué dans un premier temps à basse température au cours d'une polymérisation isotherme et d’une post-cuisson. Ensuite, une approche basée sur la méthode de caractérisation en émission/transmission a été développée afin d’étudier le comportement à haute température. La modélisation de la réponse électroacoustique par série de Debye (DSM) a été effectuée en se basant sur des approches analytiques. L’utilisation des transducteurs multiéléments permet la localisation et le dimensionnement de défauts lors du déplacement de fibres de carbone dans une résine liquide, entre des moules. / The developments based on ultrasonic transducers are nowadays numerous in the industrial non-destructive testing (NDT). Used punctually and periodically, the ultrasonic NDT is used for health diagnostics of materials. Ultrasonic characterization in real time allows a physical properties monitoring during the manufacturing of composite materials. In this context, studies are conducted in LOMC in view to optimize the manufacturing process of composite materials using RTM (Resin Transfer Molding) in order to improve the product quality. This work consists to develop ultrasonic methods for the monitoring of viscoelastic properties during the production phase of composites. The viscoelastic properties are studied using theoretical models, numerical simulations and experimental measurements. Calibration studies were carried out to study the influencing factors on the monitoring of ultrasonic properties during the RTM process. The monitoring of viscoelastic parameters of epoxy resins is performed in a first time at low temperature during an isothermal polymerization and a post-curing. Then, an approach based on the transmission mode characterization was developed to study high-temperature behavior. Based on analytical approaches, the electroacoustic response was simulated by Debye series method (DSM). The use of phased array transducers was investigated for the location and sizing of defects during the movement of the carbon fiber in a liquid resin between the molds.

This thesis is about assessment of a bridge construction influenced by fire accident. The bridge is situated at the highway D46 beyond the town Držovice. Within this construction research, there will be mentioned diagnostic methods – A non- destructive method (Ultrasonic pulse method and hardness tests) and destructive methods (borehole and tear off tests). For find out in which way was the concrete of the bridge damaged and hurt while facing a high temperature of fire, there were taken samples, which were analyzed by physical and chemical test. We can analyze composition and microstructure of the concrete. The result of this tests will be evaluated, and the actions of a remediation will be suggested.

Dans le cadre de ses actions de R&D sur la caractérisation non destructive, le CEA dispose d’un système d'imagerie photonique de haute énergie. Ce dispositif, unique en France, permet de réaliser des radiographies et des tomographies sur des objets de grands volumes, tels que des colis de déchets radioactifs. Le Laboratoire de Mesures Nucléaires, qui mène les projets de recherche sur cette installation, a engagé une évolution majeure du système en lançant l'approvisionnement d'une nouvelle source X d'énergie augmentée et d'un banc mécanique de positionnement d'une capacité de 5 tonnes afin de pouvoir caractériser des objets de grande épaisseur : jusqu'à 140 cm de béton. Les travaux qui ont fait l'objet de cette thèse s'inscrivent dans ce contexte de caractérisation et de mise en service du nouveau tomographe, qui permet la mise en place de nouvelles modalités d'examen telles que la tomographie bi-énergie.La première partie de la thèse consiste en une étude approfondie des performances du nouveau tomographe en termes de capacité de pénétration et de résolution spatiale. Elle concerne à la fois la source X et le système de détection. La source X est un accélérateur linéaire Saturne reconditionné pour atteindre des énergies comprises entre 15 et 20 MeV pour des débits de dose supérieurs à 100 Gy/min. Les caractéristiques attendues de cette source sont évaluées par simulation : spectres, taches focales et débits de dose. En parallèle, la recherche d'un système de détection adapté conduit à mettre en compétition trois détecteurs : une série de semi-conducteurs CdTe non jointifs, une caméra linéaire à scintillateur CdWO4 segmenté et des écrans horizontaux de CsI filmés par des caméras bas bruit. Tous trois font l'objet d'une analyse par comptage de quanta (Quantum Accounting Diagram) permettant de mettre en lumière les qualités et limites de chacun à travers l'évaluation et la comparaison d'indicateurs complémentaires de leurs performances : efficacité quantique de détection, rapport signal sur bruit, résolution spatiale et gamme dynamique. Cette étude théorique est complétée, corrigée et validée par des campagnes de mesures expérimentales et permet finalement de prévoir les performances attendues avec l'accélérateur Saturne, et ainsi définir le meilleur détecteur pour l'imagerie des objets ciblés.La seconde partie de la thèse concerne le développement d'une nouvelle méthode de caractérisation des matériaux par tomographie bi-énergie afin d’identifier au mieux le numéro atomique effectif du matériau et sa densité. L'état de l'art sur les techniques actuelles fait ressortir une méthode potentiellement intéressante pour les besoins de la caractérisation de colis de déchets nucléaires : la décomposition en double effet. Initialement développée pour l'imagerie de plus basse énergie, elle a été adaptée à la gamme d’énergie du tomographe en modifiant les interactions photon-matière prises en compte dans le procédé. La méthode a été testée et validée sur des simulations d'examens tomographiques obtenues avec le code de simulation MODHERATO.Il ressort de ces travaux de thèse que le nouveau système d'imagerie du CEA Cadarache devrait être en mesure à la fois d'accueillir et caractériser des objets massifs avec une qualité d'image satisfaisante et une résolution spatiale submillimétrique, mais également de mettre en œuvre des examens de tomographie bi-énergie permettant d'évaluer le numéro atomique et la densité des matériaux composant les objets examinés. / As part of its research and development activities on non-destructive characterisation, CEA utilizes a high-energy photonic imaging system. This instrument, unique in France, allows radiographic and tomographic analyses on large objects (e.g., nuclear waste drums). The "Laboratoire de Mesures Nucléaires", responsible for running research projects in the facility, has launched a major upgrade of the system by providing a new higher energy X-ray source and a new mechanical bench possessing a 5 t load, which allows the characterisation of thick objects (up to 140 cm concrete thickness). This PhD thesis concerns the characterisation and commissioning of the new computed tomography (CT) system and introduces new examination modalities, such as dual-energy CT.The first part of the thesis is a comprehensive study of the performance of the upgraded CT system, specifically regarding penetration capacity and spatial resolution and concerning both the X-ray source and the detection system. The X-ray source is a linear accelerator called Saturne, which has been repackaged to reach energies between 15 and 20 MeV with dose rates greater than 100 Gy/min. Simulation is used to assess the expected features of this source: spectra, focal spots and dose rates. Parallel comparison among three detectors -a series of non-abutting CdTe semiconductor sensors, a linear camera with segmented CdWO4 scintillators and horizontal screens of CsI filmed by low noise cameras - assessed the most suitable detection system. All three detection systems are studied using a quantum accounting analysis that highlights potentials and limitations of each system and enables measurement of complementary indicators of their performance: detector quantum efficiency, signal to noise ratio, spatial resolution and dynamic range. This theoretical study is completed, corrected and validated by experimental measurement campaigns. This extensive study predicts the expected performance when combined with the Saturne accelerator, allowing selection of the most appropriate detector for the imaging of large objects.The second part of the thesis concerns the development of a new method for the characterisation of materials by dual-energy CT, allowing a better assessment of the effective atomic number and the density of the material. The state of the art of current techniques highlights the potential interesting method for the characterising nuclear waste: the double effect decomposition. Initially developed for lower energy X-ray imaging, it has been adapted to match the energy range of the CT system by adapting the photon/matter interactions taken into account in the process. The method has been tested and validated on tomographic simulations obtained with the simulation code MODHERATO.This PhD work has shown that the new CT system of the CEA Cadarache has the potential to characterise massive objects with a satisfactory image quality and milli-scale spatial resolution. It also opens opportunities for the execution of dual-energy CT evaluations allowing the assessment of the atomic number and density of materials composing the examined objects.

Les travaux réalisés dans le cadre de cette thèse ont consisté en la réalisation d'un système de détection non destructif assisté par cavité d'atomes piégés sur réseau optique pour l'amélioration de la stabilité d'une horloge optique au strontium. La caractérisation de ce système dans son fonctionnement en régime classique, dans lequel les atomes piégés diffusent suffisamment peu de photons pour ne pas être expulsés du piège durant la détection, a mis en évidence des améliorations significatives en termes de rapport signal à bruit avec un gain d'un facteur cent en comparaison avec le système précédent de détection par fluorescence. Les gains en termes de stabilité par réduction de l'effet Dick restent cependant à concrétiser.Pour la réalisation du régime quantique, dans lequel moins d'un photon est diffusé par atome durant la détection, des idées nouvelles et des changements significatifs ont du être opérés sur le système et un travail théorique conséquent a été entrepris afin de déterminer la stratégie permettant une amélioration de la stabilité par réduction du bruit de projection quantique par mesure sans démolition de la cohérence de l'état interne atomique.J'y ai également aborder l'étude des effets des collisions chaudes des atomes de strontium piégés avec les particules du fond de vide résiduel, permettant une amélioration de l'exactitude de l'horloge. Cette thèse rapporte en particulier la première mesure expérimentale du déplacement de la fréquence de transition d'horloge due à ces collisions ainsi que son étude théorique. / The work achieved in the frame of this PhD training consisted in the implementation of a cavity enhanced non destructive detection system of atoms trapped in an optical lattice aiming at improving the stability of an optical strontium clock.The characterization of the system in its classical regime, for which a sufficiently low number of photons are scattered per atom to avoid expelling them off the trap, highlighted significant improvements in term of signal to noise ratio, with gain factor around 100 compared with the previously used fluorescence scheme. Yet, gains in terms of stability via Dick effect reduction still have to be demonstrated.Regarding the quantum regime, for which less than one photon is scattered per atom over the detection, new ideas and significant changes have been carried out on the system and a theoretical study was has been undertaken to determine the strategy for the improvement of the clock stability by quantum projection noise reduction via quantum non demolition measurement.It was as well the opportunity to study the effect of the hot collisions between the trapped strontium atoms and the residual vacuum background gas particles, allowing for the improvement of the clock uncertainty. This work reports in particular on the first measurement of strontium clock hot collisions shifts as well as its theoretical study.

Problemformulering: Hur beskriver medarbetare destruktivt ledarskap? Syfte: Studiens syfte är att beskriva destruktivt ledarskap utifrån ettmedarbetarperspektiv. Metod: Studien följer en deduktiv ansats och bygger på en kvalitativforskningsstrategi, studiens empiriska material har insamlats genomsemistrukturerade intervjuer samt bearbetats och tolkats med utgångspunkt i enkvalitativ innehållsanalys. Slutsats: Medarbetare beskriver destruktivt ledarskap som ett stort problem vilketmedför en rad allvarliga konsekvenser som därmed bör tas på allvar. Det framgårockså tydligt att medarbetares upplevelser och perspektiv är betydande för förståelsenav fenomenet destruktivt ledarskap och därför bör beaktas i större utsträckning ipraktiken. Vi kan även konstatera att organisationers sätt att hantera destruktivtledarskap riskerar att förvärra konsekvenserna för medarbetare och klienter. / Research question: How do employees describe destructive leadership? Purpose: The purpose of this study is to describe destructive leadership from anemployee perspective. Method: The study follows a deductive approach and is based on a qualitativeresearch strategy, the empirical material of the study has been collected throughsemi-structured interviews and processed and interpreted on the basis of a qualitativecontent analysis. Conclusion: Employees describe destructive leadership as a major problem whichbrings a series of serious consequences that should be taken seriously. It also appearsthat the employees experiences and perspective is significant for the understanding ofthe phenomenon of destructive leadership and therefore should be taken intoconsideration on a larger scale in practice. We can also state that the organization’sapproach to cope with destructive leadership risks worsening the consequences foremployees and clients.

The aim of this thesis is a complex evaluation of reinforcement in reinforced concrete construction and its comparation with contract documents. In the next step we will calculate static reviews for each part of the construction. In case that some of the parts will fail this review, we will have to project such a solution that the construction wont get damaged from excessive load. In the end we will make an all in all evaluation of the examination and the construction.

<p>Recently, energy storage systems have become more focused towards sustainable energy sources like LIBs due to attractive attributes like high energy density and volumetric density which make them extremely competitive compared to other energy sources for many portable and non-portable applications (smartphones, eVTOLs, stationary storage systems, electric vehicle and so on). Longer cycling stability, capacitance retentive power, lower self-discharge rate and high voltage window are qualitative features in LIB. Even though LIBs are rechargeable energy storage systems, all cells decay and degrade over time causing capacity and power fade due to a number of factors such as manufacturing defects, usage outside the normal operating conditions, and other abuse conditions like overcharge, over-discharge and indentation. This work presents a systematic investigation of several off-nominal conditions which are typically observed in LIBs such as overcharge, over-discharge, nail indentation, periodic overcharge, and over-discharge in order to form a comparative analysis on the effect of each of these conditions on cycle life aging, morphological changes on the cell components and also to evaluate potential internal short circuit (ISC) mechanisms. The cell failure mechanism induced by each condition and its negative impact on the electrochemical performance has been rigorously analyzed in this work based on the proper protocols. The correlation of the galvanostatic performance with the morphological change of the individual electrodes was also scrutinized under SEM and EDS to demarcate the severity of the defect into Li-ion cells. The practical off-nominal condition analysis of LIB will pave the way for more reliable cell functioning and recommendations to be considered to effectively analyze these off-nominal conditions. The analysis was divided into two parts; 1) curve-based analysis which included capacity fade, internal resistance, Incremental & Differential capacity analysis and EIS analysis 2) disassembly-based analysis which consisted of post-mortem visual inspection, morphology-based analysis using electron microscopy and composition analysis. From the capacity fade and IR evolution study, it was observed that periodic off-nominal conditions exhibited the highest rate of capacity fade and the greatest increase in DC internal resistance consistently. The least rate of capacity loss was shown by overcharged and no defect cells and a similar trend for DCIR values as well indicating that there was a positive correlation between capacity fade and internal resistance evolution. From the EIS study a slightly different trend was observed with the overcharged cell exhibiting the highest ohmic resistance and the no defect cell XV </p> <p>the least indicating ORI as an aging mechanism in overcharged and periodic overcharge/over-discharged cells. Another interesting observation was that the highest change in change transfer resistance was shown by over-discharged cell followed by nail-indented and overcharged cells and the least for cells subjected to periodic off-nominal conditions. This was attributed to a large amount of delamination caused by particle cracking in no defect cells causing LAM in these cells, lithium plating in Overcharged, copper current collector dissolution in over-discharged cells which resulted in LLI as the primary aging mechanism in these cells. This was further confirmed by ICA-DVA curve analysis at various capacity fades, postmortem inspection and SEM-EDS analysis. The periodic overcharged cells underwent a combination of degradation mechanisms including LAM from delamination, LLI through lithium deposition on the separators and Contact loss due to electrolyte vaporization causing active material adhesion on the separator and vice versa. The last degradation mechanism exacerbated the rate of increase of internal resistance by blocking pathways for Li+ ion diffusion. To summarize, while no defect and nail-indented cells exhibited primarily one aging mechanism (ORI) other cells exhibited a combination of degradation modes and the decoupling of these modes became increasingly indistinguishable for the cells subjected to periodic off-nominal conditions. Interestingly, no manifestation of soft or hard Internal short circuits was observed in the tested cells. However, it should be noted that for the periodic overcharged cells which underwent excessive lithium plating on the separators and charring of electrodes, dendrite formation could potentially have caused ISC upon further cycling. This cements the fact that periodic off-nominal conditions exacerbate the possibility of sudden failures and accelerate degradation in Li-ion cells. </p>

Bakgrund: Självskadebeteende är ett ökande fenomen bland världens ungdomar. Det har visat sig vara fler flickor än pojkar som självskadar. Psykisk ohälsa är en individuell uppfattning och därmed svår att definiera men det resulterar ofta i ett stort personligt lidande där en ständig kamp mellan gott och ont, lust och lidande pågår inom människan. Sjuksköterskan ska främja hälsa och lindra lidande och ett negativt bemötande har visats kunna förvärra ett självskadebeteende. Många med ett självskadebeteende har bemötts med kritik och känt skam över sitt beteende. Syfte: Syftet med denna studie var att belysa tonårsflickors upplevelser av bakomliggande orsaker till självskadebeteendet. Metod: Använd metod var kvalitativ innehållsanalys med induktiv ansats. Resultat: Ur analysen framträdde två kategorier: Utsatt för övergrepp och Känslostormarnas våld med fyra underkategorier Konklusion: Studien visar att övergrepp och känslostormar var bakomliggande orsaker och att flickorna hade svårigheter att hantera detta på egen hand. Sjuksköterskans svårigheter att bemöta tonårsflickorna med självskadebeteende kan relateras till kunskapsbrist. Studiens syfte uppnåddes då tonårsflickornas upplevelser av bakomliggande orsaker till självskadebeteendet belysts i resultatet, vilket kan ge ökad förståelse för sjuksköterskor i framtida vårdmöten. / Background: Self-destructive behavior is a growing phenomenon amongst teenagers in the world. It has proven to be more girls than boys who self-harm. Psychological illness is an individual perception and thus difficult to define but often results in a great personal suffering, where a constant struggle between good and evil, desire and suffering is going on within the person. A nurse shall promote health and alleviate suffering, and a negative attitude has been shown to worsen the self-destructive behavior. Many of the people with a self-harm behavior has been met with criticism and felt ashamed of their behavior. Aim: The aim of his study was to shed light on teenage girls’ experience of underlying causes of the self-destructive behavior.  Method: The used method was a qualitative content analysis with an inductive approach.. Results: From the analysis of the data material emerged two categories emerged: The victim of abuse and the violence of emotional storms with four subcategories. Conclusion: The study shows that abuse and emotional storms were the underlying causes and that the girls had difficulties to handle this on their own. Nurses have difficulties to meet teenage girls with a self-destructive behavior related to their lack of knowledge. The study's aim was achieved when the teenage girls' experience of what is behind the self-harm was highlighted in the results which may increase understanding of nurses in future treatment sessions.

A snapshot of the current state of the business world is given, followed by the proposition that people are the root cause of the problems therein. Mutual influence between individual and organisation is depicted. The corporate psychopath is identified as being especially problematic. Therefore measures to prevent the recruitment of psychopaths into organisations will be studied. The objectives of this research report are: • To establish whether South African organisations are aware of the problems caused by psychopaths. • To establish what screening processes are in place in South African organisations to identify psychopaths. • To suggest additional measures that would prevent the recruitment of psychopaths into organisations.