Origami, the Japanese art of paper folding, has been used previously to inspire engineering solutions for compact, deployable designs. Action origami, the subset of origami dealing with models designed to move, is a previously unexplored area for engineering design solutions that are deployable and have additional motion in the deployed state. A literature review of origami in engineering is performed, resulting in seven key areas of technical origami literature from a wide variety of disciplines. Spherical mechanisms are identified as the method by which most action origami models achieve complicated motion while remaining flat-foldable. The subset of action origami whose motion originates from spherical mechanisms is termed "kinematic origami''. Action origami is found to contain large coupled systems of spherical mechanisms. All possible action origami models are classified by their spherical mechanism structure, resulting in eight possible categories. Viewing action origami as spherical mechanisms allows the use of established equations for kinematic analysis. Several kinematic origami categories are used to demonstrate a method for the position analysis of coupled systems of spherical mechanisms. Input-output angle relationships and coupler link motions are obtained for a single spherical mechanism, two spherical mechanisms coupled together, and four spherical mechanisms coupled in a loop arrangement. This lays a groundwork from which it is possible to create compact, deployable mechanisms with motion in the deployed state.

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Most tilting pad journal bearing dynamic characteristics estimation methodologies assume perfect shaft tracking by the pads. In other words, they neglect pivot friction. In case of pads having point or line contact that operate under most normal load conditions, the pad tilting is due to a rocking motion which is not greatly influenced by friction. Hence this simplifying assumption might be acceptable. Heavier loading conditions, such as those typically encountered in gearboxes, demand the use of spherical pivots to avoid pivot failure. The spherical pivot is very attractive for this reason, but the tilting motion is rather a sliding action that must occur in the precision ball socket. A valid concern exists for verifying the soundness of assumed shaft tracking by the pads of such bearings. A "fixed test bearing, floating shaft" type of test rig previously built for determining the dynamic characteristics of bearings was accordingly modified to facilitate the testing of shaft tracking for a spherical pivot bearing. This thesis describes the modifications carried out on the rig. The special instrumentation and data acquisition systems implemented to observe the minute pad motion are also discussed. Some preliminary results of the tests are presented for various loading conditions. They show excellent shaft tracking by the pads. More detailed testing and analysis of data is required to fully understand the pad motion and tracking ability of the spherical pivot design. / Master of Science

La caractérisation et l’étude de l’homogénéisation temps réel d’un mélange de produits liquides ou solides présente une opération clé pour de nombreux domaines industriels.Dans le présent travail, nous proposons un modèle de capteur acoustique sphérique miniaturisé et autonome, adapté à des fonctions de caractérisations en ligne des milieux hétérogènes de différentes natures. Ce capteur a la possibilité d’être dispersé dans un système dynamique en constituant un réseau de capteurs géo-localisables permettant une cartographie des propriétés recherchées du milieu. Sa forme sphérique creuse nous offre la possibilité de loger une électronique programmable pour gérer son fonctionnement par unité ou dans un réseau de capteurs identifiés par codage.D’un point de vu mécanique, le résonateur proposé est assemblé à partir de deux demi-sphères faites d'un matériau approprié (Plexiglas dans le cadre de notre étude), le capteur est mis en résonance à l’aide d’un élément piézo-électrique déposé entre les deux demi-sphères ayant la forme d'un anneau.Après une validation expérimentale du système en adoptant le principe de la trilatération, une étude sur l’atténuation et la vitesse de propagation de l’onde acoustique a été effectuée dans différentes solutions à 35 °C; eau, glucose, huile de colza, lait, gel laitier et grain de caillé en suspension (différente taille). / The characterization and the study of real-time homogenization of a mixture of liquid and solid products present a key operation for many industrial sectors.In this work, we propose a model of spherical acoustic sensor miniaturized and autonomous adapted to different functions of characterization online of heterogeneous media of various kinds. This sensor has the ability to be dispersed in a dynamic system by creating a network of geo-localization for mapping desired properties of the medium. Its spherical hollow shape gives us the opportunity to accommodate a programmable electronic for managing its function as a unit or in a sensor network identified by coding.From a mechanical point of view, the proposed resonator is assembled from two hemi-spheres made of a suitable material (Plexiglas in our study), the sensor is brought into resonance by using an element piezoelectric introduced between the two hemi-spheres having the shape of a ring.After an experimental validation of the system by adopting the principle of trilateration, a mitigation study and propagation velocity of the acoustic wave was performed in different solutions at 35 ° C; water, glucose, rapeseed oil, milk, dairy and grain curd gel suspension (different sizes).

This research is concerned with the self-adaptive numerical solution of the neutral particle radiation transport problem. Radiation transport is an extremely challenging computational problem since the governing equation is seven-dimensional (3 in space, 2 in direction, 1 in energy, and 1 in time) with a high degree of coupling between these variables. If not careful, this relatively large number of independent variables when discretized can potentially lead to sets of linear equations of intractable size. Though parallel computing has allowed the solution of very large problems, available computational resources will always be finite due to the fact that ever more sophisticated multiphysics models are being demanded by industry. There is thus the pressing requirement to optimize the discretizations so as to minimize the effort and maximize the accuracy. One way to achieve this goal is through adaptive phase-space refinement. Unfortunately, the quality of discretization (and its solution) is, in general, not known a priori; accurate error estimates can only be attained via the a posteriori error analysis. In particular, in the context of the finite element method, the a posteriori error analysis provides a rigorous error bound. The main difficulty in applying a well-established a posteriori error analysis and subsequent adaptive refinement in the context of radiation transport is the strong coupling between spatial and angular variables. This research attempts to address this issue within the context of the second-order, even-parity form of the transport equation discretized with the finite-element spherical harmonics method. The objective of this thesis is to develop a posteriori error analysis in a coupled space-angle framework and an efficient adaptive algorithm. Moreover, the mesh refinement strategy which is tuned for minimizing the error in the target engineering output has been developed by employing the dual argument of the problem. This numerical framework has been implemented in the general-purpose neutral particle code EVENT for assessment.

MACHAČ Stanislav: Spherical rollers process innovation by applicaton of cold bulk forming. Diploma thesis of the attendance engineer´s studies, Institute of technology, 2nd year, 2nd level – summer term, study group 5O / 51, school year 2007 / 2008. FSI VUT Brno, department of forming and plastics, May 2008, 75 pages, 6 tables, 4 enclosures. The topic of this thesis is production innovation of spherical rollers for bearings. The innovation is based on the technology of cold bulk forming. According to the literary research and according to the current stage of production is proposed and conceived manufacturing process for cold upsetting instead of turning using in current spherical rollers production. This manufacturing process is dedicated for the bearing type 22226EJ. The production process is conceived with regard to determinate knuckle-joint press LLR 1000 (Smeral Brno, a.s.). Also with regard to determinate half-closed die upsetting and with regard to formability of the steel 100CrMn6. The proposal and check-up of tool functional parts are designed regarding the current setting of particular parts of the press. In the next part of this thesis the proposal of work-room layout dedicated for hand-filling of semi-factured product is conceived. In conclusion the comparison of spherical roller production budget between cold upsetting and turning is conceived.

Diffusion MRI (dMRI) measurements allow us to infer the microstructural properties of white matter and to reconstruct fiber pathways in-vivo. High angular diffusion imaging (HARDI) allows for the creation of more and more complex local models connecting the microstructure to the measured signal. One of the challenges is the derivation of meaningful metrics describing the underlying structure from the local models. The aim hereby is to increase the specificity of the widely used metric fractional anisotropy (FA) by using the additional information contained within the HARDI data. A local model which is connected directly to the underlying microstructure through the model of a single fiber population is spherical deconvolution. It produces a fiber orientation density function (fODF), which can often be interpreted as superposition of multiple peaks, each associated to one relatively coherent fiber population (bundle). Parameterizing these peaks one is able to disentangle and characterize these bundles. In this work, the fODF peaks are approximated by Bingham distributions, capturing first and second order statistics of the fiber orientations, from which metrics for the parametric quantification of fiber bundles are derived. Meaningful relationships between these measures and the underlying microstructural properties are proposed. The focus lies on metrics derived directly from properties of the Bingham distribution, such as peak length, peak direction, peak spread, integral over the peak, as well as a metric derived from the comparison of the largest peaks, which probes the complexity of the underlying microstructure. These metrics are compared to the conventionally used fractional anisotropy (FA) and it is shown how they may help to increase the specificity of the characterization of microstructural properties. Visualization of the micro-structural arrangement is another application of dMRI. This is done by using tractography to propagate the fiber layout, extracted from the local model, in each voxel. In practice most tractography algorithms use little of the additional information gained from HARDI based local models aside from the reconstructed fiber bundle directions. In this work an approach to tractography based on the Bingham parameterization of the fODF is introduced. For each of the fiber populations present in a voxel the diffusion signal and tensor are computed. Then tensor deflection tractography is performed. This allows incorporating the complete bundle information, performing local interpolation as well as using multiple directions per voxel for generating tracts. Another aspect of this work is the investigation of the spherical harmonic representation which is used most commonly for the fODF by means of the parameters derived from the Bingham distribution fit. Here a strong connection between the approximation errors in the spherical representation of the Dirac delta function and the distribution of crossing angles recovered from the fODF was discovered. The final aspect of this work is the application of the metrics derived from the Bingham fit to a number of fetal datasets for quantifying the brain’s development. This is done by introducing the Gini-coefficient as a metric describing the brain’s age.

I dagens samhälle finns alla möjliga sorters sjukdomar - alltifrån den vanliga säsongsinfluensan till mer allvarliga infektioner och kroniska sjukdomar som cancer och Alzheimers. Därför finns även ett stort intresse för att kunna ställa rätt diagnos samt söka möjliga behandlingar och att bota dessa sjukdomar. Ett sätt att göra detta på är genom att använda biomarkörer, IgG (Immunoglobulin G) är en biomarkör som visat sig vara passande i detta syfte. Vid användning av MALDI-TOF-MS (Matrix Assisted Laser Desorption/Ionization - Time of Flight - Mass Spectrometry) krävs dock anrikning av glykopeptiderna för att exakta resultat ska erhållas. Genom att utnyttja de starka hydrofila interaktionerna mellan glykanerna, som inte finns hos icke-glykopeptider, kan de glykosylerade peptiderna bli anrikade för att högre intensitet ska erhållas i spektrat. Därav, är syftet med detta kandidatexamensarbete att undersöka huruvida SpheriCals® kalibreringsstandarder är passande i syftet att möjliggöra- samt förbättra användandet av biomarkörer i diagnostik och andra medicinska appliceringar där prov analyseras med MALDI-TOF-MS. Hittills har andra peptidbaserade kalibranter använts och det är därför önskvärt att jämföra dessa med SpheriCal® för att se om den sistnämnda genererar mer exakta mätningar. Det första steget var glykosylering för att få glykopeptider från IgG. Därefter genomfördes experiment med både interna och externa kalibreringsmetoder för naturliga, renade samt till viss del nedbrutna peptider och mänskliga prover från friska individer samt från patienter med COVID-19. Dessa experiment genomfördes i olika matriser, mer exakt i DHB (2,4-dihydroxibensoesyra) och HCCA (α-cyano-4-hydroxikanelsyra) En sammanfattning av resultaten visar att SpheriCal®-kalibranter möjliggör mätningar med hög noggrannhet och små fel för uppmätt m/z (massa mot laddning) för både intern och extern kalibrering vid analys av IgG glykopeptider. Vid extern kalibrering gav SpheriCal®-APH mätningar med väsentligt högre exakthet än för kalibrering med mer traditionellt använt PCS i både HCCA och DHB. / Our world is full of all different kinds of diseases - everything from the regular flu to more severe infections and chronic illnesses such as cancer and Alzheimer's disease. It is therefore of interest to be able to establish a diagnosis, and thus search possible treatments and cures. One way to do this is by using biomarkers and IgG (Immunoglobulin G) has shown to be suited as one. When using MALDI-TOF-MS (Matrix Assisted Laser Desorption/Ionization -Time of Flight - Mass Spectrometry), enrichment of the glycopeptides is required to provide an accurate analysis. Hence, by utilizing the strong hydrophilic interactions of glycans, which do not exist in non-glycopeptides, the glycosylated peptides can be enriched to achieve higher intensity in the spectra. That is why the aim of this bachelor’s degree project is to investigate if SpheriCal® calibrant standards are appropriate for the purpose of enabling and bettering the use of biomarkers in diagnostics and other medical areas when analyzing samples with MALDI-TOF-MS. Until now, other peptide-based calibrants have been used. Therefore, it has been desirable to compare the two to showcase whether SpheriCal® generates more accurate measurements. An initial step was glycosylation in order to obtain glycopeptides of IgG. Following that, tests were carried out with both internal- as well as external calibration methods with natural, purified and partly digested peptides and human samples of healthy- and COVID-19 infected patients. Furthermore, different matrices were tested, more specifically, DHB (2,5-dihydroxybenzoic acid) and HCCA (α-Cyano-4-hydroxycinnamic acid). To conclude the results, they showed that SpheriCal® calibrants generate high accuracy with small m/z (mass to charge) errors, for both internal- as well as external calibration methods, when analyzing IgG glycopeptides. For external calibration, SpheriCal®-APH showed significantly higher mass accuracy than conventionally used PCS in both HCCA and DHB.