In der vorliegenden Arbeit wird die Optimierung des REXEBIS-Ladungsbrüters an der ISOLDE präsentiert. Die REXEBIS in der aktuellen Konfiguration erzeugt eine Elektronenstromdichte in der Fallenregion bei 2 T von 200A/cm² und wird bis zu ihren physikalischen Grenzen optimiert. Um diese Begrenzung zu überwinden wurde eine neue Elektronenkanone, die HEC²-Elektronenkanone, in Kooperation mit BNL konstruiert und an der TestEBIS in Betrieb genommen. Diese Elektronenkanone verspricht eine Elektronenstromdichte von mehr als 10 kA/cm² bei 5T, welche die Ladungsbrütungszeit entscheidend verkürzt. In dieser Dissertation werden neuartige Simulationstechniken vorgestellt, welche die Inbetriebnahme durch Untersuchung der Mechaniken von auftretenden Verlustströmen beschreiben. Dazu wird der Elektronenkollektor der TestEBIS nach Kompatibilität bezüglich der HEC²-Elektronenkanone, die nahe derer Designwerte betrieben wird, evaluiert. Die gewonnenen Erfahrungen von der Inbetriebnahme der HEC²-Elektronenkanone und den etablierten, numerischen Techniken führen zur Entwicklung einer kleineren hochkomprimierenden Elektronenkanone für medizinische Anwedungen, die MEDeGUN. Diese Elektronenkanone sollte einen qualitativ hochwertigen Elektronenstrahl generieren, welcher eine Elektronenstromdichte von 7.5 kA/cm² in der Fallenregion bei 5 T axialen Magnetfeld erzeugt. Eine EBIS/T, ausgestattet mit einer MEDeGUN, wird bezüglich Pulsfrequenz und bereitgestellten Ionenstrom zu Hochfrequenz-Therapiezentren der zweiten Generation kompatibel sein. / In this thesis the optimization of the REXEBIS charge breeder at the ISOLDE facility is presented. REXEBIS in its current state provides a current density of 200A/cm² inside the trapping region at 2 T and will be optimized to the physical limit of its design. To overcome this limit a new electron gun, the HEC² gun, was designed in collaboration with the BNL and is in commission at TestEBIS. This electron gun promises a current density of >10 kA/cm², which decreases the charge breeding time significantly. This thesis presents novel simulation techniques supporting the commissioning phase by explaining the sources of occurring loss current and, in addition, evaluate the currently installed collector for compatibility with the HEC² gun operating at its design limit. The experience gained from the commission of the HEC2 gun and the established numerical techniques lead to the development of a smaller high-compression electron gun for medical purposes, the MEDeGUN. This electron gun should provide a high-quality beam, which generates a calculated current density of 7.5 kA/cm² inside the trapping region immersed in a 5 T axial magnetic field. An EBIS/T equipped with a MEDeGUN will be compatible regarding the pulse frequency and deliver the mandatory ion current required for second generation therapy centers.

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The master thesis deals with the design of device used for gun prototypes testing purposes. It aims at electrical part of the design which controls a stepper motor which through mechanical gear initiates trigger of tested prototype periodically. The core of design consists of the DRV8711 integrated circuit which controls a stepper motor. The integrated circuit is using the microstepping driving technique. The main logic of designed device is controlled by PIC32 microcontroller unit which also communicates with PC through USB bus.

Hydroxyapatite coatings have been used as a barrier between a metal core of replacement and living tissue for long time in medicine. Plasma spray is a typical technology for preparation these coatings. This thesis concerns a new plasma spray technology with hybrid system of arc stabilization (WSP-H). Simultaneously it uses an innovative method of feeding the initial material in a form of water suspension (SPPS). The aim of this thesis was to produce water solutions of hydroxyapatite and make coatings with WSP-H. These coatings were characterized in terms of their morfology, chemical and phase composition. Their biocompatibility was tested by a cultivation and an analysis of RAW 264.7 and MG-63 cells. The coatings made by SPPS have a very rough surface which is suitable for biological application. The biocompatibility testing discovered that the coatings will by tolerated in a human body very well. This method of production of hydroxyapatite coatings could be a good replacement of older methods after a better optimalisation of the processing parameters and after reaching purity of coating.

The thesis is dealing with drilling deep holes. Theoretical part of thesis is focused on base knowledge of deep drilling. Experimental part deals with testing two different borers, with different cutting conditions and different purchase prize. Drilling was made into 1.2343 ESU material. Conclusion of this work is concept of purchase machinery for deep drilling.

This master thesis deals with the efficiency improvement proposal of the deburring technology of the edge of the holes intersection inside of the given part. In the introductory chapter it deals with the introduction of Česká zbrojovka a.s. company, where the creation of this thesis took place. The definition of the fire guns, some of the special products of the CZUB a.s. company and the description of the given part are following. The third chapter contains the description of the current manufacturing process. In the second part the proposals of the possible technologies are listed along with their current state. In the end a technical-economic evaluation is accomplished.

The initiation of high explosives (HEs) under shock loading lacks a comprehensive understanding: particularly at the particle scale. One common explanation is hot spot theory, which suggests that energy in the material resulting from the impact event is localized in a small area causing an increase in temperature that can lead to ignition. This study focuses on the response of HMX particles (a common HE) within a polymer matrix (Sylgard-184^®), a simplified example of a polymer bonded explosive (PBX). A light gas gun was used to load the samples at impact velocities ranging from 370 to 520 m/s. The impact events were visualized using X-ray phase contrast imaging (PCI) allowing real-time observation of the impact event. The experiments used three subsets of PBX samples: multiple particle (production grade and single crystal), drilled hole, and milled slot. Evidence of damage and deformation occurred in all of the sample types. While the necessary impact velocity for consistent hot spot formation leading to reactions was not reached, the damage (particularly cracking) that occurred provides a useful indication of where hot spots may occur when higher velocities are reached. With the multiple particle samples, evidence of cracking and debonding occurred throughout. One sample showed significant volume expansion due to possible reaction. The samples containing drilled holes demonstrated the expected pore collapse behavior at these velocities, as well as damage downstream from the holes under various two-hole arrangements. Milled slot samples were tested to simulate existing cracks in the HMX. These samples showed increased damage at the site of the milled slot, as well as unique cracking behavior in one of the samples.

In 1912 Hjalmar Söderberg wrote what came to be a Swedish classic, The serious game, about the two young lovers Lydia and Arvid and their failed attempts to be with each other. 1973 Gun-Britt Sundström responded with her own novel, For Lydia, that tells the same story but from Lydia´s point of view.  This essay discusses if the macro perspective, Sundström´s tendency in giving Lydia an agency, can be seen in the structure of the language, the micro perspective. To enable this, the essay has been using parts of the narratology theory founded in the 1960’s that was partly produced by Gérard Genette and supplemented by Mieke Bal. Looking at focalization (from what angle the story is told), it is possible to investigate what kind of information the reader can assimilate of Lydia and her progress. Susan Lanser defined feminist narratology and in accordance to her theory the essay examines the context and author of the novel to fully understand the writings. Sundström in a higher degree than Söderberg includes intern focalization when it comes to Lydia, which gives the reader more information about Lydia and her agency. Söderberg focalizes Arvid rather than Lydia which gives the reader the impression that Lydia acts selfish and unaccountable. Both novels arose in circumstances characterized by female emancipation and by regarding that, a more prominent picture of Sundström´s intention to make For Lydia a feministic response to The serious game can be seen. In conclusion, the essay shows that, the tendency of Sundström, to make a feministic response to Söderberg´s novel, can be seen even in the micro perspective of the language.

Every year children are unintentionally injured or killed due to finding an unattended firearm. Although research evaluating various approaches to teach safety skills shows that behavioral skills training and in situ training are effective, limited research exists evaluating small-scale simulation training in teaching safety skills to children. Furthermore, there is no research evaluating this approach with children with Autism Spectrum Disorder (ASD). This study evaluated the effectiveness of small-scale simulation training in teaching firearm safety to 5- to 6-year-old children with ASD. Simulation training was effective for one participant and in situ training was necessary for one participant. However, in situ training was not effective for the third participant.

Mass shootings are one of the most discussed issues in American society. While it is evident who the main victims are, the impact of such an event reaches far beyond the lives that were directly impacted. One of the main effects mass shootings have been found to have is a spike in gun sales (Wallace, 2015; Studert et. al., 2017 ; Turchan et. al., 2017). This finding has been found time and time again by academic and non-academic researchers, and it is one of the most commonly believed ideas regarding the effects of mass shootings (Aish & Keller, 2016). The current study builds on previous research to determine whether a Democratic Government has a moderating effect on the mass shootings - gun sales relationship. There are two main hypotheses. Hypothesis one is that mass shootings increase gun sales. Hypothesis two predicts that when Democrats are in power, the increase in gun sales following a mass shooting is higher than when Republicans are in power. This hypothesis comes from the idea that gun enthusiasts will not only fear attacks, but they will also fear changes in gun regulation when Democrats are in power (Adams & Daniel, 2017). To test this hypothesis, a Democratic Government variable was created, and it measured which party controls the Presidency, and holds majority at the House of Representatives, and the Senate. Using FBI background check information as a proxy for gun sales, OLS regressions determined hypothesis one did not have support, while hypothesis two was partially supported, meaning the interaction between a Democratic Government and mass shootings is relevant to gun sales. It is worth noting that this relationship went in the opposite direction than what was expected, since it was found that Democrats holding office actually lead to a decrease in gun sales following a mass shooting. An explanation for why this might be the case, and why the first hypothesis was not supported is presented. Study limitations and future research directions are also discussed.