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Retrospektive Untersuchung der digital bestimmten relativen Knochendichte nach Defektauffüllungen im Mund- Kiefer-Gesichtsbereich mittels phasenreinen Hydroxyl-apatits unter Berücksichtigung der klinischen Verläufe / Retrospective investigation of the digitally determined relative bone density after defect filling in the oral-maxillo-facial region with a phase-pure hydroxyapatite taking into account the clinical coursesGeiger, Manuel 18 February 2020 (has links)
No description available.
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Robotic in-line quality inspection for changeable zero defect manufacturingAzamfirei, Victor January 2021 (has links)
The growing customer demands for product variety have put unprecedented pressure on the manufacturing companies. To maintain their competitiveness, manufacturing companies need to frequently and efficiently adapt their processes while providing high-quality products. Different advanced manufacturing technologies, such as industrial robotics, have seen a drastic usage increase. Nevertheless, traditional quality methods, such as quality inspection, suffer from significant limitations in highly customised small batch production. For quality inspection to remain fundamental for zero-defect manufacturing and Industry 4.0, an increase in flexibility, speed, availability and decision upon conformance reliability is needed. If robots could perform in-line quality inspection, defective components might be prevented from continuing to the next production stage. Recent developments in robot cognition and sensor systems have enabled the robot to carry out perception tasks they were previously unable to do. The purpose of this thesis is to explore the usage of robotic in-line quality inspection during changeable zero-defect manufacturing. To fulfil this aim, this thesis adopts a mixed-methods research approach to qualitative and quantitative studies, as well as theoretical and empirical ones. The foundation for this thesis is an extensive literature review and two case studies that have been performed in close collaboration with manufacturing companies to investigate how in-line quality inspection is perceived and utilised to enhance industrial robots. The empirical studies also aimed at identifying and describing what opportunities arise from having robotic in-line quality inspection systems. The result of this thesis is a synthesis of literature and empirical findings. From the literature review/study, the need for enhancing quality inspection was identified and a multi-layer quality inspection framework suitable for the digital transformation was proposed. The framework is built on the assumption that data (used and collected) needs to be validated, holistic, and online, i.e. when needed, for the system to effectively decide upon conformity to surpass the challenges of reliability, flexibility and autonomy. Empirical studies show that industrial robotic applications can be improved in precision and flexibility using the in-line quality inspection system as measurement-assisted. Nevertheless, this methodological changes and robot application face the hurdle of previous and current management decisions when passing from one industrial paradigm to another (e.g. mass production to flexible production). A discussion on equipment design and manufacturing process harmony and how in-line quality inspection and management can harmonise such a system was provided.
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Characterization of Post-Plasma Etch Residues and Plasma Induced Damage Evaluation on Patterned Porous Low-K Dielectrics Using MIR-IR SpectroscopyRimal, Sirish 05 1900 (has links)
As the miniaturization of functional devices in integrated circuit (IC) continues to scale down to sub-nanometer size, the process complexity increases and makes materials characterization difficult. One of our research effort demonstrates the development and application of novel Multiple Internal Reflection Infrared Spectroscopy (MIR-IR) as a sensitive (sub-5 nm) metrology tool to provide precise chemical bonding information that can effectively guide through the development of more efficient process control. In this work, we investigated the chemical bonding structure of thin fluorocarbon polymer films deposited on low-k dielectric nanostructures, using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Complemented by functional group specific chemical derivatization reactions, fluorocarbon film was established to contain fluorinated alkenes and carbonyl moieties embedded in a highly cross-linked, branched fluorocarbon structure and a model bonding structure was proposed for the first time. In addition, plasma induced damage to high aspect ratio trench low-k structures especially on the trench sidewalls was evaluated both qualitatively and quantitatively. Damage from different plasma processing was correlated with Si-OH formation and breakage of Si-CH3 bonds with increase in C=O functionality. In another endeavor, TiN hard mask defect formation after fluorocarbon plasma etch was characterized and investigated. Finding suggest the presence of water soluble amines that could possibly trigger the formation of TiN surface defect. An effective post etch treatment (PET) methods were applied for etch residue defect removal/suppression.
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Inovace systému pro detekci defektů solárních článků pomocí elektroluminiscence / Inovation of system for electroluminiscence defect detection of solar cellsLepík, Pavel January 2017 (has links)
This master thesis analyses the existing methods both practically and theoretically used to detect defected surface area in solar cells. Various methods were used but by using an upgraded CMOS camera without IR filter to implement the electroluminescence method, this has proven to have a very crucial impact on the results. Given the overall results and the acquired information, a procedure with a simple parameter can be setup to carry out the measurements. In addition to this a catalog was formed showing the defects occurring in mono and polycrystalline solar cells.
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Standardizace znaleckých postupů při zjišťování vad projektové dokumentace vypracované do roku 1949 / Standardization of expert methods in detecting defects in design documentation developed by 1949Urbánek, Zdeněk January 2018 (has links)
The work is focused on defining the methodology expert procedures for detecting defects in the project documentation in 1949. No legislation or literature this issue far more does not, it is a specific area that the project documentation defects generally are. The methods of the research study; analysis of documents; classification; Analysis - synthesis; induction - deduction; abstraction; comparison (comparison) case studies. Dissertation is focused on creating a systematic procedure for processing expertise, assessing defects in the design documentation in a limited period from 1880 to 1949.
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Hluboké neuronové sítě pro detekci anomálií při kontrole kvality / Deep Neural Networks for Defect DetectionJuřica, Tomáš January 2019 (has links)
The goal of this work is to bring automatic defect detection to the manufacturing process of plastic cards. A card is considered defective when it is contaminated with a dust particle or a hair. The main challenges I am facing to accomplish this task are a very few training data samples (214 images), small area of target defects in context of an entire card (average defect area is 0.0068 \% of the card) and also very complex background the detection task is performed on. In order to accomplish the task, I decided to use Mask R-CNN detection algorithm combined with augmentation techniques such as synthetic dataset generation. I trained the model on the synthetic dataset consisting of 20 000 images. This way I was able to create a model performing 0.83 AP at 0.1 IoU on the original data test set.
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Diagnosis of Pneumatic Cylinders Using Acoustic Emission Methods / Diagnosis of Pneumatic Cylinders Using Acoustic Emission MethodsMahmoud, Houssam January 2019 (has links)
Tato práce se zabývá vývojem nového efektivního diagnostického postupu pro kontrolu funkce pneumatických válců pomocí metody akustické emise. Cílem práce bylo navrhnout a určit diagnostická kritéria pro hodnocení kvality vybraných typů pneumatických válců. Prvním krokem bylo nalezení typického akustického emisního signálu, který je spojen s určitým typem poškození ve válci využitím frekvenčního spektra signálu. Později byl tento parametr nahrazen parametrem RMS během sledování změn v průběhu testů. Na konkrétních válcích byl sledován vztah mezi akustickou emisí a různými typy defektů a byl představen nový přístup k určování těchto typů vad a jejich odlišením v signálu akustické emise. Druhý krok studie že neporušené a poškozené válce byly porovnávány tak, aby se zjistily výrazné rozdíly, které určují, zda je válec poškozen nebo nepoškozen. Několik nepoškozených válců bylo testováno akustickou emisí a následně v nich byly vytvořeny umělé vady. Signály z vysouvání a zasouvání pístu byly zaznamenány a analyzovány pomocí řady parametrů. Na základě časového zpoždění a normalizace RMS byly rozpoznány odezvy mezi poškozenými a nepoškozenými pneumatickými válci. Rozdíly byly zjištěny porovnáním maximální hodnoty RMS ze snímače upevněného na předním víku válce a snímače upevněného na zadním víku válce pro jeden cyklus. Poškozené a nepoškozené válce byly rozlišeny pomocí rozdílů energetických hodnot přítomných v signálech z obou snímačů v závislosti na zdvihu pístu. Konečné vyhodnocení válce bylo určeno výpočtem celkové hodnoty RMS. Ve třetím kroku experimentu byly válce postupně zatěžovány různými závažími ve svislém směru. Signály akustické emise byly zaznamenány z vysouvání a zasouvání pístu a poté analyzovány. Časové zpoždění se vypočítává z digitálního vstupu a začátku pohybu pístu. Energie signálu a RMS akustické emise porovnávají různé reakce v poškozených a nepoškozených pneumatických válcích s a bez zatížení. Výsledky testu ukázaly lineární vztah mezi křivkou RMS a zatížením. Defekty ovlivňují vztah mezi aplikovaným zatížením a zaznamenaným signálem snímačů.
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Vady tlakově litých odlitků ze slitin hliníku / Defects of high pressure die cast castings from aluminum alloysDočekal, Václav January 2019 (has links)
This thesis is focused on defects occurring in products made by high pressure die casting of aluminum alloys. The theoretical part includes introduction to high pressure die casting technology and description of individual defects, causes and corrective procurations. The practical part focuses on the determination of the defect on the pre-selected casting, which is cast in the foundry ALW INDUSTRY, s.r.o. Based on the identification of the defect, there is a corrective procuration to reduce its occurrence.
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Evolution of artificial defects during shape rollingMirjana, Filipovic January 2007 (has links)
Very often defects are present in rolled products. For wire rods, defects are very deleterious since the wire rods are generally used directly in various applications. For this reason, the market nowadays requires wire rods to be completely defect-free. Any wire with defects must be rejected as scrap which is very costly for the production mill. Thus, it is very important to study the formation and evolution of defects during wire rod rolling in order to better understand and minimize the problem, at the same time improving quality of the wire rods and reducing production costs. The present work is focused on the evolution of artificial defects during rolling. Longitudinal surface defects are studied during shape rolling of an AISI M2 high speed steel and a longitudinal central inner defect is studied in an AISI 304L austenitic stainless steel during ultra-high-speed wire rod rolling. Experimental studies are carried out by rolling short rods prepared with arteficial defects. The evolution of the defects is characterised and compared to numerical analyses. The comparison shows that surface defects generally reduce quicker in the experiments than predicted by the simulations whereas a good agreement is generally obtained for the central defect.
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A Primer to Categorical Symmetries and Their Application to QCD in Two DimensionsOlofsson, Rikard January 2021 (has links)
We introduce the formalism of categorical symmetries, and examine how these appear in quantum field theories. We discuss rational conformal field theories and their Verlinde lines, with the critical Ising model as an example. We introduce Wess Zumino Witten models and affine Lie algebras. An algorithm for the fusion rules is presented. We use bosonization to realise two dimensional adjoint SU(N) QCD as a WZW coset model plus a kinetic term for the gauge field. We argue that the infrared theory has degenerate vacua acted upon by a non-negative integer valued matrix representation of a categorical symmetry. We compute generators for these matrices for gauge groups SU(3) and SU(4).
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