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The development of both experimental and diagnostic equipment to assist with simulating the mechanical effects of cold X-ray deposition is covered by this work. This thesis reviews the various experimental techniques suitable for conducting the electromagnetic launch of flyer plates and the chosen technique is developed into a fully functional experimental facility. The development of a bespoke 1-dimensional computer model is also described in the text. A novel current distribution measurement technique is also fully described. This new diagnostic approach will allow the variation of the current across the width of a large conductor to be easily determined which is something not previously demonstrated.

Gas bearings in oil-free micro-turbomachinery for process gas applications and for power generation (< 400 kW) must offer adequate load capacity and thermal stability, reliable rotordynamic performance at high speeds and temperatures, low power losses and minimal maintenance costs. The metal mesh foil bearing (MMFB) is a promising foil bearing technology offering inexpensive manufacturing cost, large inherent material energy dissipation mechanism, and custom-tailored stiffness and damping properties. This dissertation presents predictions and measurements of the dynamic forced performance of various high speed and high temperature MMFBs. MMFB forced performance depends mainly on its elastic support structure, consisting of arcuate metal mesh pads and a smooth top foil. The analysis models the top foil as a 2D finite element (FE) shell supported uniformly by a metal mesh under-layer. The solution of the structural FE model coupled with a gas film model, governed by the Reynolds equation, delivers the pressure distribution over the top foil and thus the load reaction. A perturbation analysis further renders the dynamic stiffness and damping coefficients for the bearing. The static and dynamic performance predictions are validated against limited published experimental data. A one-to-one comparison of the static and dynamic forced performance characteristics of a MMFB against a Generation I bump foil bearing (BFB) of similar size, with a slenderness ratio L/D=1.04, showcases the comparative performance of MMFB against a commercially available gas foil bearing design. The measurements of rotor lift-off speed and drag friction at start-up and airborne conditions are conducted for rotor speeds up to 70 krpm and under identical specific loads (W/LD =0.06 to 0.26 bar). The dynamic force coefficients of the bearings are estimated, in a ‘floating bearing’ type test rig, while floating atop a journal spinning to speeds as high as 50 krpm and with controlled static loads (22 N) applied in the vertical direction. The parameter identification is conducted in the frequency range of 200-400 Hz first, and then up to 600 Hz using higher load capacity shakers. A finite element rotordynamic program (XLTRC2) models a hollow rotor and two MMFBs supporting it and predict the synchronous rotor response for known imbalances. The predictions agree well with the ambient temperature rotor response measurements. Extensive rotor response measurements and rotor and bearing temperature measurements, with a coil heater warming up to 200 ºC and placed inside the hollow rotor, reveal the importance of adequate thermal management. The database of high speed high temperature performance measurements and the development of a predictive tool will aid in the design and deployment of MMFBs in commercial high-speed turbomachinery. The work presented in the dissertation is a cornerstone for future analytical developments and further testing of practical MMFBs.

Geo-data visualization has always been an important tool in the urban planning process. Recent trends in geo-information technology are, however, offering additional opportunities for the development of new visualization tools. In parallel, developments have also taken place in the field of urban planning, which has evolved from the rational planning model towards a more strategic planning process with a greater emphasis on collaboration and inclusiveness. This study investigates how an innovative geo-data visualisation tool can be used to develop more inclusive and participatory planning processes, and it tests this approach by means of a case study in Tripoli, Lebanon. The study compared two geo-data visualization techniques regarding their potential for an increased involvement of different types of stakeholders in the urban planning processes: The first technique employed coloured printed transparency maps of the present land-use and the 2000-2020 Master Plan, both geo-referenced to a mosaic of QuickBird satellite imagery used to assist the participant’s orientation. The second technique was the Lenticular Foil Display (LFD) using the so-called flip effect, also based on the geo-coding of the same three “layers”. By tilting this product the observer was easily able to interpret the changes between present and planned state. The LFD technology is particularly useful for true-3D (auto-stereoscopic) viewing. Statistical evaluations of questionnaires concerning sociological and perception-scientific aspects revealed interesting details regarding the role of the new visualization method in the participatory city planning process. The result of the interviews revealed that all stakeholders were readily able to participate in the planning process and to contribute their ideas by sketch-map drawing and writing, using the LFD technology. Regarding the possibilities to stimulate the participation of different stakeholders in the planning process, the LFD was found to be more effective than the conventional approach using transparencies overlaid over orthophotos. Non-experts, in particular, preferred the LFD technology to the transparent overlays which were, however, the preferred approach for the professionals and experts familiar with Master Plan map-reading. One conclusion of the present study is that an efficient participatory urban-planning process should explicitly consider the level of map-reading skills of the stakeholders. Geo-data visualization products like the Multi-Flip-LFDs and other innovative approaches offer possibilities to improve stakeholder participation. The monograph closes by making concrete suggestions for further research into the development and optimization of LFDs.

In this study, procedures were developed to produce ultra-clean, ultra-thin target foils and to remove x-ray interference from electron bremsstrahlung and low energy K-shell x-rays from contaminant elements.

Geo-data visualization has always been an important tool in the urban planning process. Recent trends in geo-information technology are, however, offering additional opportunities for the development of new visualization tools. In parallel, developments have also taken place in the field of urban planning, which has evolved from the rational planning model towards a more strategic planning process with a greater emphasis on collaboration and inclusiveness. This study investigates how an innovative geo-data visualisation tool can be used to develop more inclusive and participatory planning processes, and it tests this approach by means of a case study in Tripoli, Lebanon. The study compared two geo-data visualization techniques regarding their potential for an increased involvement of different types of stakeholders in the urban planning processes: The first technique employed coloured printed transparency maps of the present land-use and the 2000-2020 Master Plan, both geo-referenced to a mosaic of QuickBird satellite imagery used to assist the participant’s orientation. The second technique was the Lenticular Foil Display (LFD) using the so-called flip effect, also based on the geo-coding of the same three “layers”. By tilting this product the observer was easily able to interpret the changes between present and planned state. The LFD technology is particularly useful for true-3D (auto-stereoscopic) viewing. Statistical evaluations of questionnaires concerning sociological and perception-scientific aspects revealed interesting details regarding the role of the new visualization method in the participatory city planning process. The result of the interviews revealed that all stakeholders were readily able to participate in the planning process and to contribute their ideas by sketch-map drawing and writing, using the LFD technology. Regarding the possibilities to stimulate the participation of different stakeholders in the planning process, the LFD was found to be more effective than the conventional approach using transparencies overlaid over orthophotos. Non-experts, in particular, preferred the LFD technology to the transparent overlays which were, however, the preferred approach for the professionals and experts familiar with Master Plan map-reading. One conclusion of the present study is that an efficient participatory urban-planning process should explicitly consider the level of map-reading skills of the stakeholders. Geo-data visualization products like the Multi-Flip-LFDs and other innovative approaches offer possibilities to improve stakeholder participation. The monograph closes by making concrete suggestions for further research into the development and optimization of LFDs.

The aim of this project was to, based on a given idea, develop and evaluate a method for measuring residual stress in thin PVD coatings. AlCrN was deposited, by PVD, on thin circular samples of stainless steel foil and the radius of the emerged curvature was measured using an optical profilometer. From the radius data the residual stress in the coating of each sample was calculated. The foil samples examined were of two different thicknesses, 0.3 mm and 0.5 mm. With the parameters of the project the foils of 0.3 mm were found most suitable. Furthermore, the method was compared to an already established method where depositions are made on thicker substrates, which are then ground to an appropriate thickness. A correlation factor between the two methods was calculated and found to be 0.91 ± 0.28. Finally, the possibility of adapting the method in running production was investigated. Cost and time analyses were conducted and both supported the applicability of the method. / Projektets syfte var att utveckla och utvärdera en metod för att mäta restspänningar i tunna PVD-beläggningar utifrån en redan befintlig idé. Tunna cirkulära prover av rostfritt stål belades med AlCrN genom PVD och radien på den utböjning som uppstod mättes med en optisk profilometer. Restspänningen bestämdes sedan utifrån den uppmätta radien. Folier av två olika tjocklekar, 0,3 mm och 0,5 mm, utvärderades. Med de processparametrar som användes i projektet visades att folien med tjocklek 0,3 mm var den bäst lämpade. Metoden jämfördes även med en etablerad metod där tjocka substrat beläggs och sedan slipas ned till lämplig tjocklek. En korrelationsfaktor som relaterar de två metoderna bestämdes till 0,91 ± 0,28. Slutligen undersöktes möjligheterna att använda metoden i löpande produktion. Kostnads- och tidsanalyser utfördes och resultaten stödjer metodens användbarhet.

Wall-Couture is a project within the textile design field, which aims to explore methods for surface design in digitally printed wallpaper. Through a practice based working method, textile after-treatment techniques have been used to manipulate digitally printed wallpaper with hand-painted motives. Practices borrowed from haute couture have influenced the working method. The result is a range of design examples displaying various expressions of the techniques. The project shows that several surface materials could be applied in ways that enhance tactility and visual depth to digitally printed wallpaper, and also that methods from craftsmanship could be use to design contemporary wallpaper. The combination of techniques increases the designer’s opportunities to design wallpaper by using alternative approaches to material and surfaces. The work also strives to higher the value of handicraft, decoration and ornamentation in the design field. Another value is to strengthen the position of digital printing in the textile industry; the work encourages technical progress for creating digital print in combination with surface treatments.

Approved for public release; distribution is unlimited / A three dimensional analysis of the intensity distribution of backward optical transition radiation has been performed. The effects of variations in electron energy and beam divergence and on material properties such as dielectric permittivities and the resultant coherence length upon the angular distribution and polarization of optical transition radiation has been investigated. A surprising observation important to the use of optical transition radiation as a diagnostic tool for high energy electron beams is the behavior of the perpendicular component of the intensity. In contrast to low energies where the parallel component dominates, at electron energies above 200 MeV, the perpendicular component dominates. This requires the use of a polarization filter to diagnose particle beam properties at high energies. / http://archive.org/details/threedimensional00long / Lieutenant, United States Navy

The generalized data which are presented in this thesis are the culmination of the determination of the foil depression factor using oblate spheroidal coordinates.