The present work was carried out within the framework of the priority programme SPP 2045. Technical ultra–fine particle systems (< 10μm) from highly specific separation processes are to be investigated here with regard to multi–dimensional property distributions. Tomographic measurement methods allow a comprehensive 3D description of particle–discrete data sets of statistically relevant size. The focus of the work is on X–ray tomographic analysis by means of micro-computed tomography (micro–CT), which, if necessary, is extended to several size scales by including further measurement methods (nano–CT) and supplemented by suitable elemental analysis (FIB–SEM + EBSD, EDX). Two preparation methods (wax, epoxy resin) for different particle preparations are described methodically, which have already been published in a case study or are the subject of current studies in the outlook of the work. Finally, a networked multiple use of the generated data within an online particle database is shown and its application is explained using three concrete examples.:1 Outline 2 Description of Particle Properties 2.1 Integral or Class–Based Description 2.2 Particle–Discrete Description 2.2.1 2D Description 2.2.2 Full 3D Description 2.3 Multidimensional Characterization on Basis of Particle–Discrete 3D Data 2.3.1 Motivation 2.3.2 Kernel Density Approach 2.3.3 Copula Approach 3 X–ray Tomography 3.1 Historical Context 3.2 X–ray Physics 3.2.1 X–ray Generation 3.2.2 Polychromatic Spectrum 3.2.3 Interaction with Matter 3.3 Tomographic Imaging 3.3.1 Motivation 3.3.2 Basic Idea 3.3.3 X–ray Microscopy Measurement Setup andWorkflow 3.3.4 Tomographic Reconstruction via Filtered Back Projection 3.3.5 Region of Interest Tomography 3.4 Relevant Artefacts Related to Particle Measurement 3.4.1 Temperature Drift 3.4.2 Penumbral Blurring and Shadow 3.4.3 Cone Beam 3.4.4 Out–of–Field 3.4.5 Center Shift 3.4.6 Sample Drift 3.4.7 Beam Hardening 3.4.8 Rings 3.4.9 Noise 3.4.10 Partial Volume 3.4.11 Summary 4 Practical Implementation 4.1 Particle Sample Requirements 4.1.1 Geometry 4.1.2 Dispersity and Homogeneity 4.2 Statistics 4.2.1 Single Particle Properties 4.2.2 Properties of a Limited Number of Particles (10 to several 100) 4.2.3 Particle Populations with Distributed Properties 4.3 2D Validation 4.4 Measurement 4.4.1 X–ray Microscope 4.4.2 Source Filter 4.4.3 Detector Binning 4.4.4 Cone Beam Artefact Compensation 4.4.5 Center Shift Correction 4.4.6 Dynamic Ring Removal 5 Image Analysis 5.1 Image Quality 5.1.1 Grey Value Histogram 5.1.2 Resolution 5.1.3 Signal–to–Noise Ratio 5.1.4 Contrast and Dynamic Range 5.1.5 Sharpness 5.1.6 Summary 5.2 Basic Image Processing Strategies 5.2.1 Threshold–Based Segmentation 5.2.2 Machine Learning Assisted Segmentation 6 Correlative Tomography 6.1 Scouting Approach 6.2 Multiscale Approach 6.3 Multidisciplinary Approach 7 Data Management 7.1 Data Quality 7.2 Data Availability 7.2.1 Tomographic Datasets 7.2.2 Particle Database 8 Outlook on Further Research Activities 9 Publications 9.1 Copyright Declaration 9.2 Overview 9.3 List of Publications Paper A, Preparation techniques for micron–sized particulate samples in X–ray microtomography Paper B, Self–constructed automated syringe for preparation of micron–sized particulate samples in X–ray microtomography Paper C, Preparation strategy for statistically significant micrometer–sized particle systems suitable for correlative 3D imaging workflows on the example of X–ray microtomography Paper D, Multi–scale tomographic analysis for micron–sized particulate samples Paper E, PARROT: A pilot study on the open access provision of particle discrete tomographic datasets 10 Appendix 10.1 Application Example 1: Fracture Analysis 10.2 Application Example 2: 3D Contact Angle Measurement 10.3 Influence of the Source Filter 10.4 Influence of the X–rays on the Sample 10.5 Appropriate Filter Settings 10.6 Log File Parser / Die vorliegende Arbeit ist im Rahmen des Schwerpunktprogramms SPP 2045 entstanden. Technische Feinstpartikelsysteme (< 10μm) aus hochspezifischen Trennprozessen sollen hier hinsichtlich mehrdimensionaler Eigenschaftsverteilungen untersucht werden. Tomographische Messverfahren erlauben dabei eine vollständige 3D Beschreibung partikeldiskreter Datensätze statistisch relevanter Größe. Der Schwerpunkt der Arbeit liegt auf der röntgentomographischen Analyse mittels Mikro–Computertomographie (mikro–CT), die im Bedarfsfall unter Einbeziehung weiterer Messmethoden (nano–CT) auf mehrere Größenskalen erweitert und durch geeignete Elementanalytik (FIB–SEM + EBSD, EDX) ergänzt wird. Methodisch werden zwei Präparationsverfahren (Wachs, Epoxidharz) für unterschiedliche Partikelpräparate beschrieben, welche in einer Fallstudie bereits veröffentlicht bzw. im Ausblick der Arbeit Gegenstand aktueller Studien ist. Schließlich wird eine vernetzte Mehrfachnutzung der erzeugten Daten innerhalb einer online-Partikeldatenbank gezeigt und deren Anwendung an drei konkreten Beispielen erläutert.:1 Outline 2 Description of Particle Properties 2.1 Integral or Class–Based Description 2.2 Particle–Discrete Description 2.2.1 2D Description 2.2.2 Full 3D Description 2.3 Multidimensional Characterization on Basis of Particle–Discrete 3D Data 2.3.1 Motivation 2.3.2 Kernel Density Approach 2.3.3 Copula Approach 3 X–ray Tomography 3.1 Historical Context 3.2 X–ray Physics 3.2.1 X–ray Generation 3.2.2 Polychromatic Spectrum 3.2.3 Interaction with Matter 3.3 Tomographic Imaging 3.3.1 Motivation 3.3.2 Basic Idea 3.3.3 X–ray Microscopy Measurement Setup andWorkflow 3.3.4 Tomographic Reconstruction via Filtered Back Projection 3.3.5 Region of Interest Tomography 3.4 Relevant Artefacts Related to Particle Measurement 3.4.1 Temperature Drift 3.4.2 Penumbral Blurring and Shadow 3.4.3 Cone Beam 3.4.4 Out–of–Field 3.4.5 Center Shift 3.4.6 Sample Drift 3.4.7 Beam Hardening 3.4.8 Rings 3.4.9 Noise 3.4.10 Partial Volume 3.4.11 Summary 4 Practical Implementation 4.1 Particle Sample Requirements 4.1.1 Geometry 4.1.2 Dispersity and Homogeneity 4.2 Statistics 4.2.1 Single Particle Properties 4.2.2 Properties of a Limited Number of Particles (10 to several 100) 4.2.3 Particle Populations with Distributed Properties 4.3 2D Validation 4.4 Measurement 4.4.1 X–ray Microscope 4.4.2 Source Filter 4.4.3 Detector Binning 4.4.4 Cone Beam Artefact Compensation 4.4.5 Center Shift Correction 4.4.6 Dynamic Ring Removal 5 Image Analysis 5.1 Image Quality 5.1.1 Grey Value Histogram 5.1.2 Resolution 5.1.3 Signal–to–Noise Ratio 5.1.4 Contrast and Dynamic Range 5.1.5 Sharpness 5.1.6 Summary 5.2 Basic Image Processing Strategies 5.2.1 Threshold–Based Segmentation 5.2.2 Machine Learning Assisted Segmentation 6 Correlative Tomography 6.1 Scouting Approach 6.2 Multiscale Approach 6.3 Multidisciplinary Approach 7 Data Management 7.1 Data Quality 7.2 Data Availability 7.2.1 Tomographic Datasets 7.2.2 Particle Database 8 Outlook on Further Research Activities 9 Publications 9.1 Copyright Declaration 9.2 Overview 9.3 List of Publications Paper A, Preparation techniques for micron–sized particulate samples in X–ray microtomography Paper B, Self–constructed automated syringe for preparation of micron–sized particulate samples in X–ray microtomography Paper C, Preparation strategy for statistically significant micrometer–sized particle systems suitable for correlative 3D imaging workflows on the example of X–ray microtomography Paper D, Multi–scale tomographic analysis for micron–sized particulate samples Paper E, PARROT: A pilot study on the open access provision of particle discrete tomographic datasets 10 Appendix 10.1 Application Example 1: Fracture Analysis 10.2 Application Example 2: 3D Contact Angle Measurement 10.3 Influence of the Source Filter 10.4 Influence of the X–rays on the Sample 10.5 Appropriate Filter Settings 10.6 Log File Parser

Der Reibkontakt zwischen zwei Körpern hat entscheidende Einflüsse auf die Schwingungsselbsterregung. Da in der Literatur bisher vorwiegend ein Festkörper-Festkörper-Kontakt im Fokus steht, beschäftigt sich diese Arbeit mit einem Partikel-Festkörper-Kontakt. Dabei stehen Partikelsysteme in Form von Schüttgütern im Mittelpunkt. Ein bekanntes Beispiel solcher selbsterregten Schwingungen sind Silovibrationen. Dies sind Stick-Slip-Schwingungen beim Entleerungsvorgang von dünnwandigen Metallsilos. Untersuchungen mittels Fouriertransformation zeigen, dass die hörbaren Schwingungen sich aus einer Grundharmonischen und mehreren Oberwellen zusammensetzen. Diese Frequenzen sind allerdings weit oberhalb der numerisch untersuchten ersten Eigenfrequenzen der Silos. Ein Schwerpunkt der Arbeit liegt in den experimentellen Untersuchungen der Stick-Slip-Frequenz eines Schüttgut-Wand-Systems in einem speziell dafür entwickelten Versuchsstand. Es werden sowohl Systemkenngrößen, wie z.B. Geschwindigkeit, Systemsteifigkeit oder Masse, als auch tribologische Kenngrößen, wie z.B. Kontaktfläche oder -pressung, Materialkombination und Wandbeschaffenheit, auf ihren Einfluss auf die Stick-Slip-Frequenz untersucht. Ergänzend dazu wird die reale Kontaktfläche im statischen Zustand und bei einer äußeren dynamischen Anregung zwischen den Randpartikeln und einem Festkörper untersucht. Des Weiteren wird der tatsächliche Reibwert über der Relativgeschwindigkeit in Form einer Reibhysterese gemessen. In den Simulationsstudien wird ein Modell eines Reibschwingers vorgestellt und untersucht. Hier zeigen sich bereits bei einer stationären Kennlinie große Unterschiede in der Stick-Slip-Neigung und der Frequenz. In einer Modellerweiterung mittels einer zeitabhängigen Reibhysterese werden weiterführende Modellstudien getätigt. Hierbei steht vor allem das zeitabhängige Reibverhalten in der Haft- und Gleitphase im Fokus der Untersuchungen. / The friction contact between two bodies has an important influence on self-excited vibrations. Often the main focus is on a solid-solid contact. Therefore, this thesis focuses on a particle-solid contact, represented as the interaction between a bulk solid and a wall. Silo vibrations are a well known example of this kind of self-excited vibrations. Stick-slip vibrations occure during the discharging of thin walled metal silo. The hearable vibrations consist of a basic harmonic and some higher harmonics. The frequencies can be detected by a Fourier transform. One main focus of this thesis is the experimental investigation of the stick-slip frequency of a bulk solid-wall system. Therefore, a special test rig is designed. The investigation concentrates on system parameters, e.g. velocity, system stiffness or mass, on tribological parameters, e.g. contact area, pressure, material combination and wall surfaces, and their influence on the stick-slip frequency. Additional, the real contact area between particles in wall proximity and the wall itself is investigated in a static situation and during an external dynamic excitation. Furthermore, the real friction coefficient over the relative velocity will be measured. A model of a single mass friction oscillator will be presented and investigated in the simulation studies. Even with stationary friction characteristics this studies show big differences in the stick-slip stability and frequency. Henceforth, an advanced model with friction characteristics dependent on time in the form of a friction hysteresis is presented. There, the main focus is on the time dependent friction behaviour during the stick and slip phase of the oscillation.

Denna rapport ar resultatet av ett examensarbete som har utforts vid institutionen for informationsoch kommunikationsteknik, Kungliga Tekniska Hogskolan (KTH), och omfattar 15 hp. Rapporten presenterar ett arbete dar examensarbetarna har utvecklat en terrang med hojdskillnader och ljussattning, partikeleffekter (CPU-GPU implementering) som liknar ett fyrverkeri, partikeleffekter (GPU implementering) som visar olika monster samt en kamera for att kunna observera spelvarlden fran alla mojliga olika vinklar i 3D med API:et Lightweight Java Game Library (LWJGL). LWJGL ar ett lagniva-API som riktar sig mot nyborjare och professionella spelutvecklare i programspraket Java. Flera tekniker exponeras istallet for att mappa lagniva-funktioner i objektorienterad programmeringsparadigm som manga javautvecklare ar vana vid. LWJGL hanterar sin egen grafik, ljud och styrkontroller enbart for att fa en solid grund for moderna spel och en battre anvandarupplevelse. Den grafiska renderingen skots med OpenGL. Syftet med det har examensarbetet var att utvardera LWJGL om den ar kompetent nog att anvandas i samband med spelutveckling. Det ar kant att Java Standard Edition (Java SE) har valdigt daligt stod for grafikintensiva och komplexa applikationer dar prestandan ar valdigt viktig. Darfor utvecklade vi en storre grafiskt kravande applikation, for att kunna gora en samlad bedomning om hur det ar att arbeta med LWJGL och vad det erbjuder en spelutvecklare. Arbetet delades upp i tre olika faser. Den forsta fasen borjade med att skapa en kravspecifikation for den produkt som skulle utvecklas, den lag till grund for hela arbetet. Nasta steg var datainsamling med syfte att erhalla forstaelse for olika tekniker och att identifiera problem. Den tredje fasen var sjalva utforandet dar vi designade, implementerade, testade och analyserade losningarna iterativt. Rapporten ger lasaren en oversikt over de krav som stallts pa prototypen, den projektmetod som anvants, tekniker som har tillampats, alla losningar som har tagits fram och varfor LWJGL blev utvald bland manga andra. Enligt de tester som utforts sa ar partikelsystem A (CPU-GPU implementering) bra mycket langsammare an partikelsystem B (GPU implementering) rent prestandamassigt. Nar 1,5 miljoner partiklar renderades sa fick partikelsystem A 5 bilder per sekund och partikelsystem B 110 bilder per sekund. Ingenjorsmassiga metoder och standarder har anvants under hela arbetets forlopp som forvarvats under civilingenjorsutbildningen informationsteknik pa KTH med inriktning datalogi. Det innefattar agil systemutveckling, programmering och problemlosning. Goda kunskaper i Java, matematik och allman IT-teknisk bakgrund forutsatts for att hanga med i alla resonemang i denna rapport. / This report is the result of a thesis work done at the Department of Information and Communication Technology, Royal Institute of Technology (Swedish: Kungliga Tekniska hogskolan, abbreviated KTH), and includes 15 credits. The report presents a work in which graduate students have developed a terrain with elevation changes and lighting, particle effects (CPU-GPU implementation) displaying fireworks, particle effects (GPU implementation) which displays different patterns as well as a camera in order to observe the game world from all sorts of different angles in 3D utilizing the API Lightweight Java Game Library (LWJGL). LWJGL is a low-level API that targets beginners and professional game developers alike in the Java programming language. Several technologies are exposed instead of mapping low-level features of object-oriented programming paradigm, which many Java developers are used to. LWJGL handles its own graphics, sound and controllers just to get a solid foundation for the modern game and an improved user experience. The graphical rendering is handled using OpenGL. The aim of this thesis was to evaluate LWJGL if it is competent enough to be used in conjunction with game development. It is known that the Java Standard Edition (Java SE) has very poor support for graphics-intensive and complex applications where performance is very important. Therefore, we developed a more graphically demanding application, in order to make an overall assessment of how it is to work with LWJGL and what it offers game developers. The work was divided into three different phases. The first phase began with creating a specification for the product to be developed which became the basis of the whole work. The next step was data collection with the objective to obtain an understand the different technologies and identify problems. The third phase was the actual execution where we designed, implemented, tested and analyzed solutions iteratively. The report provides the reader with an overview of the requirements imposed on the prototype, the project methodology, technologies that have been applied, all the solutions that have been developed and why LWJGL was chosen among many others. According to the tests conducted, particle system A (CPU-GPU implementation) is much slower than particle system B (GPU implementation) purely performance-wise. When 1,5 million particles were rendered, particle system A got 5 Frames per second (FPS) and particle system B 110 FPS. Engineering methods and standards were used throughout the work process acquired during the Information Technology Engineering degree at KTH majoring in computer science. It includes agile systems development, programming and problem solving. Good knowledge of Java, mathematics and a general IT technical background is required to keep up with all the information in this report.