La compréhension et la modélisation d'un contact lubrifié en présence de texturation nécessitent une description physique très fine pour comprendre les analyses contradictoires et pour expliquer les résultats très différents en termes de performance présentes dans la littérature internationale. De nombreuses études théoriques et expérimentales ont montré que la texturation des surfaces pourrait améliorer les caractéristiques tribologiques des contacts. La capacité de charge, le coefficient de frottement et la résistance à l'usure sont les principales caractéristiques susceptibles d'être améliorées. La texturation de surface fait appel à de nombreux paramètres géométriques, qui peuvent agir de façon très différente selon le contact. Enfin, les phénomènes supposés expliquer l'apport de la texturation ne font pas l'unanimité dans la communauté scientifique. Ainsi, les différentes contradictions font que ce domaine de recherche est en pleine évolution.Dans ce contexte scientifique, l'objectif principal de cette thèse est de conduire, à travers une étude théorique et numérique approfondie, vers une meilleure compréhension des effets induits par la texturation dans un contact lubrifié. Les paramètres géométriques, essentiels par rapport aux phénomènes physiques générés, font l'objet d'une analyse étendue. Les éléments théoriques obtenus à travers cette étude permettront une optimisation opérationnelle de tous types de dispositifs fonctionnant dans un milieu lubrifié. Parmi ces nombreuses applications, la butée en régime hydrodynamique a été choisie afin d'illustrer la pertinence des résultats de nos recherches. / Understanding and modeling a lubricated contact in the presence of surface textures requires a refined physical description in order to comprehend and explain the contradicting results that are currently presented in international literature. An increasing number of theoretical and experimental studies have shown that surface texturing could improve the tribological properties of lubricated or even dry contacts. The load-carrying capacity, the friction coefficient or the wear resistance are the main characteristics that can be improved through texturing. Nevertheless, the lubrication mechanisms that might explain these effects are still the subject of debate within the scientific community. These various contradictions have lead to a significant development of this particular field of research. In this scientific context, the main objective of this thesis is to lead, by means of a thorough numerical and theoretical analysis, towards a better understanding of the physical effects induced by surface texturing in lubricated contacts. The geometrical parameters, which are essential with regard to the generated effects, are submitted to a detailed investigation that also takes into account the influence of the operating conditions (surface speed, viscosity, ambient pressure etc.). The theoretical conclusions obtained throughout this investigation should lead to an improvement in texture design and should allow an optimization of most devices operating in lubricated conditions. Among these various applications, the hydrodynamic thrust bearing has been chosen in order to illustrate the relevance of our findings.

The objective of this thesis is to investigate how the onboard battery of a quadcopter can be charged through manual rotation of its motors, while understanding the resulting aerodynamical forces acting on the rotors during hover, as well as considering the changes in thrust capabilities when the electronic and structural design are altered. A theoretical approach using the momentum theory will present a general understanding of rotor performance whilst describing the correlation between rotor parameters, thrust and mechanical power. Furthermore, the idea of using the motors as generators are put under study to investigate their electrical output and utilize them to recharge the battery. This is done using the counter electromotive force equation, and a sequence of other equations that will present numerical data of actual manual work converted into electrical power. Resulting in the required time to manually recharge the quadcopter subsequently sustaining hover flight for three minutes. It is concluded in this report that manual recharging of the battery using the motors as generators is possible, as well as maintaining its flying ability in case of added weight. Although not deemed practical in commercial use, it is a new methodology with the intention to develop a sustainable quadcopter further expanding its practical applications in both aviation industry and human aid.

Task of this diploma thesis is to design service lift which is driven by unordinary mechanism using thrust chain. Main parts of this diploma are design and description of main construction parts, strength analysis and drive design.

Le roulement est un élément essentiel dans la conception des machines tournantes. À l'échelle industrielle, sa défaillance peut avoir de coûteuses conséquences. La maintenance prédictive sert à minimiser les coûts d'entretien et à prévenir de l'état de fatigue du composant mécanique. Dans ce cadre, nous proposons une étude de l'endommagement par fatigue de contact de roulement appliquée au cas des butées à billes. Cette étude se structure en deux axes : numérique et expérimental. Le premier consiste à établir une modélisation numérique tridimensionnelle dynamique du passage cyclique d'une bille sur une bande de roulement en présence d'un indent, en utilisant la méthode des éléments finis. L'estimation de l'évolution de la taille d'un défaut d'écaillage initié en surface en fonction des cycles de chargement est effectuée. Ces résultats sont en adéquation avec les essais en laboratoire effectués dans les mêmes conditions à l'aide d'un banc d'essais de fatigue dédié aux butées à billes. Le deuxième axe consiste à déterminer un indicateur vibratoire utilisant l'analyse modale et permettant d'estimer le niveau d'endommagement de la butée à billes in situ en présence d'indent. La technique développée dans ces travaux permet de suivre l'évolution des valeurs de l'amortissement modal en fonction des cycles de vie, évolution déterminée à partir des essais en modes statique et dynamique. Cette étude contribuera à l'estimation de la durée de vie résiduelle du composant mécanique après apparition d'un écaillage en surface, en utilisant la méthode des éléments finis et en prenant compte de l'état d'endommagement de la structure. / The bearing is an essential element in the design of rotating machines. In an industrial context, bearing failure can have extremely costly consequences. Predictive maintenance minimizes the intervention costs and warns about the state of fatigue of the mechanical component. In this frame, we propose a study of the rolling contact fatigue damage applied to thrust ball bearings. This study is twofold: numerical and experimental. The first axis consists in establishing a dynamic three-dimensional numerical model of the cyclic shift of a ball on a running surface in the presence of an indent, using the finite element method. An estimation of the size evolution of a surface initiated spall depending on loading cycles is also performed. These results are consistent with laboratory tests executed in the same conditions using a fatigue test rig dedicated to ball bearings. The second axis consists in determining a vibratory indicator using modal analysis to estimate the on-line structural damage level of the ball bearing in the presence of an indent. The technique developed in this work enables monitoring the evolution of the modal damping values based on the life cycles determined from tests in static and dynamic modes. This study will contribute to estimate the residual life of the mechanical component after onset of a spall using the finite element method and accounting for the structural damage state.

This diploma thesis deal with project of servis lift drive by special mechanism using thrust chain. There are designed and descrobed the most importana construction unit of servis lift in the this thesis. The calculation as tha static for the main part sof the lift are included in the constructional analysis. The most attention is pay to drive, which is consist of eletric motor, clech, gearbox, break and imposition of sprocket wheel.

This diploma thesis deals with axial thrust existence in a double suction pump rotor. Axial thrust appears especially in low flow rates modes. The aim of this work is finding information about this issue and deriving mathematical model of calculation which will be subsequently applied on experimental data received from double suction pump measurement in laboratory. It is important to examine the whole dynamics of axial thrust development and find its cause of formation in measured double suction pump.

This diploma thesis discusses the issue of the fluid flow instabilities due to rotating discs. It also deals with the calculation of axial force in centrifugal pumps and pressure distribution on cover and support disc of the impeller. Computational simulation of rotating disc is presented with the aim of capturing flow instabilities. Next computational simulation focuses on modelling a gap between the support disc (rotor) and the stator part of the pump for three different geometries, where axial force, pressure distribution on the support disc and loss torque are calculated for each of three models. Obtained results are then compared with the experiment in the conclusion

I den här dokumentanalysen har offentliga verksamheters medarbetar- och ledarpolicys analyserats i syfte att genom en kvalitativ innehållsanalys undersöka hur tillit och styrning uttrycks i policy. Utifrån syftet togs två forskningsfrågor fram: 1) Om och i så fall på vilket sätt är tillit synligt i dessa policys? 2) Vem är chefen och vem är medarbetaren i dessa dokument? För att besvara syftet analyserades 15 policys från kommuner, regioner och statliga verksamheter. Resultatet visar att tillit är synligt genom att verksamheterna utgår från kärnverksamheterna och att medarbetarens kompetenser lyfts fram som viktiga verktyg för att nå nöjda kunder och leverera en bra välfärd. Enlig policyerna är medarbetarna professionella genom att vara en ansvarstagande medskapare som är rak och tydlig med sina medarbetare och har kunden i centrum. Ledaren i verksamheterna är lyhörda genom tydlighet i sin kommunikation, de är måluppfyllare och möjliggörare samtidigt som de agerar som förebilder för sina medarbetare och har tillit till deras förmågor. / In this document analysis, public sector employees and management policies have been analyzed in order to investigate how trust and leadership are expressed in policy through a qualitative content analysis. Based on the purpose, two research questions were raised: 1) If and if so, in what way is thrustbased leadership visible in these policies? 2) Who is the manager and who is the co-worker in these documents? To answer the purpose, 15 different policies from municipalities, regions and government agencies were analyzed. The result shows that trust is visible through the fact that the operations are based on the core operations and the co-workers skills are highlighted as important tools for reaching satisfied customers and delivering good welfare. In accordance with the policies, the co-workers are professional by being a responsible co-creator who is straightforward and clear with their coworkers and has the customer at the center. The leaders are responsive in the operations and clear in their communication, they are goal fulfillers and enablers while at the same time acting as role models for their employees and having confidence in their abilities.

The aim of this thesis is to design a service lift according to given parameters, which is actuated by a special mechanism featuring a thrust chain. The opening of the thesis presents basic categorization of lifts. Following chapters are dealing with the design of the lift itself, including selection of components and functional calculation according to ČSN EN 81-1. The final part contains technical comparison with hydraulic lifts. Relevant technical drawings are also part of the thesis.

Bakgrund Volleyboll är en fysiskt ansträngande idrott som framför allt ställer höga krav på utövarens explosivitet, snabbhet och styrka, där behovet av förmågorna varierar beroende på spelarposition. Med beaktande av den begränsade mängd studier som undersöker olika prestationsförmågor mellan spelarpositioner hos kvinnliga volleybollspelare finns det ett behov av ytterligare studier som undersöker dessa aspekter. Syfte Undersökningens primära syfte var att statistiskt analysera fysiska prestationsförmågor under säsong hos kvinnliga volleybollspelare på semi-elitnivå med målet att identifiera lämpliga tester för populationen. Det sekundära syftet var att kartlägga och beskriva de fysiska prestationsförmågorna hos populationen. Metod Tvärsnittsundersökning med kvantitativ ansats. Datainsamlingen bestod av fem fältbaserade fysiska tester samt tre maximala styrketester. Tio (n=10) aktiva kvinnliga volleybollspelare på semi-elitnivå deltog i undersökningen. Resultat I analysen noterades vissa signifikanta korrelationer mellan testerna. 3 RM Squat korrelerade statistiskt med Vertikal Hoppförmåga (r= 0,668, p= 0,035) samt 3 RM Hip Thrust (r= 0,721, p= 0,019). 3 RM Hip Thrust korrelerade inte mot något av hopptesterna. För Standing Long Jump (SLJ) noterades ingen signifikant korrelation mot övriga tester. Ett starkt signifikant samband konstaterades mellan Sittande Stöt Med Medicinboll (SMBT) och 3 RM Bänkpress (r= 0,775, p= 0,008). RAST och Beep-testet korrelerade signifikant mot varandra (r= 0,690, p= 0,040), dock inte mot övriga tester. I kartläggningen noterades skillnader i prestationsförmåga hos populationen, där de största skillnaderna observerades hos centerspelarna i styrketesterna och VJT.  Slutsats VJT och 3 RM Squat tycks vara de mest lämpliga testerna för utvärdering av hopp och styrkeförmåga hos kvinnliga volleybollspelare under säsong. Även SMBT och 3 RM Bänkpress verkar vara lämpliga test för utvärdering av prestationsförmåga för övre extremiteterna. RAST-testet var inte ett användbart test för populationen, Beep-testet kan dock användas för att kartlägga konditionsnivån. Med beaktning till resultatet av undersökningen förefaller kartläggning av kvinnliga volleybollspelares prestationsförmågor under säsong genom lämpliga tester vara viktigt för att kunna identifiera skillnader i prestationsförmågor mellan olika spelarpositioner och inom samma spelarposition. / Background Volleyball is a physically demanding sport which puts a high demand on the player's anaerobic, speed, and muscular capabilities, where the requirement for these capabilities is dependant on the player's position. Considering the small number of studies examining physical capabilities in various player positions in female volleyball, more studies examining these aspects are needed.  Aim The primary aim of the study was to statistically analyze physical capabilities during the season in female volleyball players at the sub-elite level to identify appropriate tests for the population. The secondary aim was to map and describe the physical capabilities of the population. Method A Cross-sectional study with a quantitative approach was conducted. The subjects performed five field-based physical tests and three maximal muscular tests. Ten (n=10) female volleyball players at the sub-elite level participated in the study. Results Significant correlations were noted between some of the tests. 3 RM Squat correlated significantly with Vertical Jump Test (VJT) (r= 0,668, p= 0,035) and 3 RM Hip Thrust (r= 0,721, p= 0,019). 3 RM Hip Thrust did not correlate with any of the jump tests. No significant correlation was noted between the Standing Long Jump (SLJ) and other tests. A strong correlation was observed between the Seated Medicine Ball Toss Test (SMBT) and 3 RM Bench press (r= 0,775, p= 0,008). The RAST and Beep-test correlated significantly but not against any other test. (r= 0,690, p= 0,040). Differences in physical capabilities were observed in the mapping, where the largest differences were noted in the middle-blocker position for the maximum strength tests and VJT. Conclusion VJT and 3 RM Squat seem to be the most appropriate tests for evaluating jump and strength capabilities in the lower extremities. In addition, the SMBT and 3 RM Bench press both seem to be appropriate tests for evaluating performance in the upper extremities. The RAST-test does not seem to be a useful test for the population, the Beep-test however can be used to evaluate aerobic performance. Based on the findings of this study, mapping physical capabilities in female volleyball players through appropriate tests during the season seems to be important in order to detect differences in physical capabilities between player positions and within player positions.