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Pneumatic drives are an integral part of many machinery, with high demands on their reliability. Unfortunately, they sometimes fail, either due to improper production or assembly at the factory or by gradual degradation of moving parts and sealing elements during operation. Current diagnostic methods do not allow localization or identification of the type of damage and do not allow the operator to make a qualified decision. This work deals with the use of acoustic emission for these purposes. On PB type cylinders manufactured by Poličské strojírny a.s., a methodology is introduced which leads to the direct identification or at least localization of selected defects. By implementing this methodology in the final inspection of the production plant, the percentage of exposed pieces of waste will be increased, thus preventing accidents of these faulty pieces during operation.

Fenomenet ledarskap har sedan länge intresserat forskare från en mängd olika discipliner. Främst har fokus varit på att finna ett allmängiltigt normerande grundrecept utifrån rationella ansatser. Trots en stor mängd vetenskapliga studier, främst baserade på kvantitativt underlag, återstår frågor av mellanmänsklig natur. I sökandet efter det goda och konstruktiva ledarskapet har forskningen den senaste tiden allt mer intresserat sig för fenomenet tillit. Den här studien syftar till att skapa en djupare förståelse för faktorer som bidrar med tillit i ledarskaps sammanhang. I synnerhet berör frågeställningarna vilka faktorer som påverkar tillit i ledarskapet och i organisationer. Främst används beteendeperspektiv som förklaringsmodell. Som underlag för vidare antaganden tolkas empiri från intervjuer. Studien påvisar flera samband mellan redovisade teorier och empiri. Men det finns också flera diskrepanser. Resultatet anger att ett antal faktorer främjar tillit mellan chef och medarbetare. Dialog och återkoppling framträder exempelvis som två viktiga faktorer. Omvänt påverkar s.k. låt-gå ledarskap eller icke-ledarskap medarbetarna och effekten destruktivt. Det framhålls också betydelsen av att organisationen signalerar en tillåtande kultur, att det är tillåtet att göra misstag. Samt att den enskilda chefen har förmåga att skydda medarbetaren från negativ respons. Vidare konstateras också att de vedertagna normativa och rationellt välregisserade teorierna ofta skiljer sig från de tillfrågades mer turbulenta realitet. I intervjuerna framkommer ett samstämmigt behov av att chefer skall tillföra struktur och spelregler. Den kontext som presenteras i studien antas begränsa chefers handlingsförmåga att praktisera de välbeforskade kvantitativa teorierna. Studien påvisar också att konsekvensbedömningar av förväntad respons påverkar medarbetares initiativ. Det är i överenstämmelse med teorin, men där är perspektivet ofta inriktat på relationen chef och medarbetare. Studien indikerar istället att det framförallt är konsekvensbedömningar gentemot kollegor som styr medarbetarnas beteende. Sammantaget påvisar studien att tillit ären viktig faktor i det goda ledarskapet, om än inte den allena saliggörande. Snarare än att vara en enskild agens är tillit en del av en syntes. Utifrån studiens utfall rekommenderas att ytterligare underlag samlas in kring chefers verklighet, för att närmare förstå hur de vedertagnateorierna kan användas praktiskt. Vidare förordas ytterligare undersökningar gällande kollegors inverkan på tillit och beteende. / The phenomenon “leadership” has interested researchers from a variety of disciplines for a long time. The main focus has been on finding a normative and universal formula based on rational approaches. Despite a large number of scientific studies, mainly based on quantitative data, questions about the impact of interpersonal relations remain. In the search for the good and constructive leadership, research has recently become increasingly interested in the phenomenon “trust”. This study aims to create a deeper understanding of factors that contribute to trust in a leadership context. In particular issues concerning which factors that affect trust in organizations and in leadership. Behavioral perspectives are mainly used as the explanatory model. As a basis for further assumptions empirical data from interviews are interpreted. The study demonstrates several connections between theories and empirical data. But there are also several discrepancies. The results indicate that a number of factors promote trust between manager and employees, e.g. dialogue and feedback appear to be important. Conversely, “laissez-faire” or “non-leadership” impact employees and organizational effect in a destructive way. The importance of the organization signaling a tolerant culture is also emphasized, that it is permissible to make mistakes. It’s also vital that managers have the ability to protect the employee from negative feedback. Furthermore, it is also stated that the most common normative and rational theories often differ from the more turbulent reality of the respondents. The results also show that there is a need from managers to add structure and rules within the organizations. The context presented in the study is assumed to affect managers' ability to practice the well-researched quantitative theories. The study also shows that consequence assessments of expected response affects initiatives. This is in line with theory, but the perspective is usually focused on the relationship between manager and employee. Instead, the study indicates that it is primarily impact assessments between colleagues that govern employees' behavior. In summary, the study shows that trust is an important factor in constructive leadership, although not the only prevailing one. Rather than being a single agent, trust is a part of a synthesis. Based on the results of the study, it is recommended that further data is collected regarding managers' reality, in order to better understand how the well researched quantitative theories can be used in practice. Furthermore, more studies of how colleagues impact trust and behavior are advocated, in order to verify the interpretations.

The thesis summarizes the basic knowledge of Wirebonding. It also closely studying the various influences on the final shape, strength and reliability of the bonds. In the experimental part are found the optimal settings of various wire bonders. For wire bonder TPT HB-10 are found the optimal settings for different types of surfaces, which were contacted.

Bc. Veronika Turková Improvement of nonconformities control system Master´s thesis, Institute of metrology and quality assurance, Brno University of technology This thesis deals with the issue of improving the management system of nonconformities control in a company ALSTOM Power, s.r.o. ALSTOM Group, the Division of boilers production, located in Brno. This thesis contains an analysis of current status of nonconformities control process and designs a new nonconformity control process using a new internal database for resolving of nonconformities. These measures should deal with the efficiency of the management of nonconformities process and reduce current company pains.

The presented innovative magnetic testing method utilises the fact, that each commercially available electromagnet can not only be used as an actuator, but also comprises internal sensor functions. This allows a huge application variety in the fields of non-destructive testing and condition monitoring of electromagnetic systems during production and within the application in the field.

Significant and influential sociologist Max Weber was one of the earliest scientists to conduct studies and establish a definition of a sect. The main characteristic of a sect is a religious and rebellious movement that defies the current and ruling societal norms and values. The study examines three focal points through a qualitative method with a deductive approach; how research defines sects, psychological factors that encourage an individual to pursue a membership and the recruitment process.Using empirical data collected from two documentaries; Jonestown: Terror in the jungle and Wild Wild Country, a total of 9 hours 19 minutes of empirical data have been processed in order to critically review sects. Results demonstrated that members who seek out sects come from a wide range of social classes and backgrounds. The common denominator is the pursuit of safety, love and community in a bid to fulfill a void and feelings of meaningless brought on by hard times. Previous members of sects describe a wide range of factors, such as marital problems, a modernized world, war, poverty and racial tensions. The weakened state of the individual during difficult times is used and exploited by members of a sect in order to attract a new member.

This work developed a novel experiment in order to determine the operational effects on a Lithium-ion battery (LIB) when a test resulting in non-catastrophic damage is performed. Accepted industry standards were used as a basis to develop a nail penetration test that would puncture a cell approximately halfway through during normal cycling at a rate of 1C, then allow the cell to continue cycling to determine how its operation was affected. The cells under test continued cycling after the punctures, showing that the experiment would be able to provide useful information on the topic. The experiment was found to be successful in simulating the operation of a cell in an abusive environment, such as those seen in electric vehicles and aerospace applications.<div><br></div><div>The results of these experiments showed that a sharp increase in temperature is observed immediately after the puncture, similar to cells that underwent tests with full penetrations. The temperatures then slowly decreased during the first few cycles after the puncture as the generated heat was dissipated through convection. The experiments also showed that it is possible for a LIB under test to continue operating for a short time after being punctured. However, the capacity and useful life of the cells were greatly reduced. The initial capacity of each cell decreased by approximately 11% after the initial impact, then continued decreasing at an accelerated rate during the ensuing cycling. The lifetime of the cells was also greatly reduced, with each cell reaching its end of life within approximately 15-75 cycles after the punctures. An analysis of the incremental capacity curves of the cells indicated that accelerated aging occurred due to both a loss of active material and a loss of lithium inventory. The information gained from the experiments gives insight into the operation of cells that experience abusive environments and will be useful in designing improved control systems, as well as promoting the development of more robust testing and safety standards for different types of cells.<br></div>

Non-destructive testing is of great value in cases where a structure's future is investigated to find out what the best measure is. It is not always the best solution to demolish and build new. Many structures can be repaired and function several more years. In this thesis the main goal is to investigate some different non-destructive techniques and learn more about difficulties and strengths. The test subjects will be a cast T-beam in a laboratory environment as well as a case study of a railway bridge in Abisko.   The different testing equipment being used in this thesis is a covermeter, a rebound hammer and ultrasonic pulse velocity. For both the T-beam and the bridge the results are overall very good. The covermeter is proven to be both easy to use and very reliable and the ultrasonic pulse velocity was more to learn about and more difficult but is giving very good results as well.   Conclusions after the thesis project is that it requires a lot of experience of the user and time to make non-destructive testing useful and competitive in the society. Getting all the pieces together it is a powerful tool that hopefully is a sustainable asset in the future, regarding both economic and environmental issues.

L'évaluation et le contrôle non destructifs (E.C.N.D.) des matériaux et des structures sont une problématique industrielle très importante dans les domaines du transport, de l'aéronautique et du spatial, et dans le milieu médical. La thermographie infrarouge active est une technique d'E.C.N.D qui consiste à apporter une excitation extérieure afin d'entraîner une élévation de température dans le matériau, puis à évaluer le champ de température résultant à la surface. Cependant, les excitateurs thermiques utilisés (lampes flash, halogènes, lasers) agissent uniquement sur la surface du matériau. Plusieurs systèmes de conversion d'énergie peuvent en revanche mener à l'apparition de sources volumiques : on peut citer en particulier les phénomènes de thermo-acoustique, de thermo-induction, de thermomécanique ou de thermochimie. Par exemple, une excitation par ondes ultrasonores peut entraîner des sources thermiques volumiques si le matériau est viscoélastique ou s'il y a présence de défaut. La reconstruction de ces sources est donc la première étape permettant de remonter aux paramètres responsables de l'échauffement. Caractériser une source thermique consiste à reconstruire sa géométrie et la puissance qu'elle génère. Cependant, l'identification de sources thermiques volumiques par la mesure des champs de température de surface est un problème mathématiquement mal posé. Le caractère diffusif de la température en est le principal responsable. Dans ce travail, la reconstruction 3D des sources volumiques à partir du champ de température résultant à la surface, mesuré par InfraRouge, est étudié. Tout d'abord, une analyse du problème physique permet de spécifier les limites de la reconstruction. En particulier, un critère sur la résolution spatiale atteignable est défini et une limitation de reconstruction pour les sources en profondeur est mise en lumière. Ensuite, une méthode de reconstruction par approche probabiliste est proposée et comparée aux méthodes d'inversions existantes. Le temps d'exécution et la sensibilité au bruit de mesure sont étudiés pour chacune de ces méthodes. Des applications numériques et expérimentales seront enfin présentées pour illustrer les résultats. / Non Destructive Testing (N.D.T.) of materials and structures is a very important industrial issue in the fields of transport, aeronautics and space and in the medical domain. Active infrared thermography is a N.D.T. method that consists in providing an external excitation to cause an elevation of temperature field in the material and then to evaluate the resulting temperature field at the surface. However, thermal exciters used (flash lamps, halogen, lasers) act only on the surface of the sample. Several energy conversion systems can on the other hand lead to the generation of volumetric sources: the phenomena of thermo-acoustic, thermo-induction, thermomechanic or thermochemistry can be cited. For example, ultrasonic waves can generate volumetric heat sources if the material is viscoelastic or if there is a defect. The reconstruction of these sources is the first step for the quantification of parameters responsible of the heating. Characterizing a heat source means reconstructing its geometry and the power it generates. For example, a defect in a structure and / or the viscoelasticity of a material can be detected and quantified by this technique if it acts directly on temperature field. However, identification of volumetric heat sources from surface temperature fields is a mathematical ill-posed problem. The diffusive nature of the temperature is the main cause. In this work, the 3D reconstruction of the volumetric heat sources from the resulting surface temperature field, measured by InfraRed, is studied. First, an analysis of the physical problem enables to specify the limits of the reconstruction. In particular, a criterion on achievable spatial resolution is defined and a reconstruction limitation for in-depth sources is highlighted. Then, a probabilistic approach for the reconstruction is proposed and compared to existing inverse methods. The computation time and noise sensitivity are studied for each of these methods. Numerical and experimental applications will thus be presented to illustrate the results.