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An Exploration of the Virtual Digital Twin Capture for Spatial Tasks and its ApplicationsVedapalle Sri Sai Swarup Reddy (12468435) 27 April 2023 (has links)
<p>Our generation is currently at the juncture of the fourth industrial revolution - Industry 4.0. Emergent technology such as Augmented Reality (AR), Internet of Things (IoT), Artificial Intelligence (AI), cloud computing, big data, and ore are at the center of this. Amidst all these, the concept of digital Twinning is a promising technology for realizing Industry 4.0. Simply put, a Digital Twin is a virtual representation of a real task, action, or object. This thesis explores the parameters and details required to generate a Digital Twin. Using these insights, we propose two applications that utilize digital twinning - EditAR and AnnotateXR. EditAR is an AR workflow for authoring kinesthetic instructions for spatial tasks. AnnotateXR is an Extended Reality (XR) workflow for automating data annotation to support multiple Computer Vision (CV) applications. We evaluate these systems through user studies and report the results on the usability and viability of these workflows. From an evaluation study, EditAR received an average system usability score (SUS) of 82.0. Over the course of a user study, using AnnotateXR, users were able to generate a total of 112,737 semantically segmented images and 144 videos annotated for action segmentation in 66.55 minutes. AnnotateXR received an average SUS score of 91.0.</p>
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Integration of Digital Twin and Deep Learning for facilitating Smart Planning and Construction: An Exploratory AnalysisKor, Mergen January 2021 (has links)
The Architecture, Engineering, and Construction (AEC) industry is known to be overwhelmed with resource planning, risk management, and logistic challenges, resulting in design defects, project delivery delays, cost overruns, and contractual disputes. These challenges have instigated research in the application of advanced machine learning algorithms such as Deep learning (DL) to help with diagnostic and prescriptive analysis of causes and preventive measures. Construction 4.0 develops through continuous innovations towards digitalization and intelligence, in order to realize a considerable boost in automation, productivity, and reliability. The Digital Twins, as the next level of planning and process control and automation towards Construction 4.0, will incorporate cognitive features that enable sensing complex and unpredicted behavior and reason about dynamic strategies for process optimization to support decision-making. However, there is still a lack of awareness regarding the real impact of DT integration, DL, and IoT, all connected to self-learning hybrid models with proactive cognitive capabilities for smart planning and construction. This study investigates the potential integration of DT and DL to facilitate smart planning and construction through an explorative analysis to identify and close this gap. Data were collected from global industry experts in a mixed approach with interviews, focus groups, and a survey focusing on the applicability and interoperability of DL integrated DT with decision-support capabilities for process optimization. Based on the results of quantitative and qualitative analyses, a conceptual model of the framework has been developed. The evaluations support that the DL integrated DT model will incorporate cognitive abilities to detect complex and unpredictable actions and reasoning about dynamic process optimization strategies to support decision-making in smart planning and construction. / Pre-study for SPARK-SBE potential project
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Genetische Epidemiologie krankheitsrelevanter Messwerte in der Allgemeinbevölkerung / QTL-Analysen an ZwillingenBusjahn, Andreas 13 September 2011 (has links)
Das Jahr 2000 wird oft als Meilenstein der Entwicklung der Humangenetik bezeichnet. Eine Relevanz für die praktische Medizin erlangt das Humangenom-Projekt jedoch erst, wenn die Funktion der einzelnen Gene in komplexen physiologischen Systemen und die genetische Variabilität aufgeklärt sind. Die hier vorgelegten Studien beruhen auf der Annahme, dass der Einfluss genetischer Variabilität nicht nur im Vergleich kranker und gesunder Menschen sichtbar wird, sondern auch in der Variabilität physiologischer Parameter in der Allgemeinbevölkerung nachweisbar ist. Grundlage aller Studien war eine medizinische Untersuchung von gesunden eineiigen und zweieiigen Zwillingspaaren. Es wurde für Kennwerte des Herz-Kreislauf-Systems die Stärke genetischer Einflüsse (Heritabilität) bestimmt. Weiterhin erfolgten Kopplungs- und Assoziationsanalysen mit ausgewählten Kandidatengenen. Der Einfluss spezifischer Gene auf die Blutdruckregulation, die Herzgröße, EKG-Parameter sowie Blutfette konnte nachgewiesen werden. Weiterhin wurde der prinzipielle Nachweis erbracht, dass die funktionelle Untersuchung einzelner Gene in unausgelesenen Stichproben realisierbar ist. / The year 2000 is often called a milestone in the history of human genetics. The knowledge of the sequence of the human genome will only become relevant for clinical medicine when the function of genes within complex physiological systems as well as the genetic variability will be revealed. The studies reported here are based on the assumption that the influence of genetic variability does not only become obvious by comparison of affected and unaffected subjects but is as well detectable in the variability of physiological parameters in the general population. All studies are based on testing healthy mono- and dizygotic twins. We determined the heritability of various cardiovascular parameters. Furthermore selected candidate genes were tested by linkage and association analyses. We could demonstrate the influence of specific genes on blood pressure regulation, heart size, ECG and lipids. These studies are a proof of principle for the functional analysis of single genes in unselected random samples.
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Variational models in martensitic phase transformations with applications to steelsMuehlemann, Anton January 2016 (has links)
This thesis concerns the mathematical modelling of phase transformations with a special emphasis on martensitic phase transformations and their application to the modelling of steels. In Chapter 1, we develop a framework that determines the optimal transformation strain between any two Bravais lattices and use it to give a rigorous proof of a conjecture by E.C. Bain in 1924 on the optimality of the so-called Bain strain. In Chapter 2, we review the Ball-James model and related concepts. We present some simplification of existing results. In Chapter 3, we pose a conjecture for the explicit form of the quasiconvex hull of the three tetragonal wells, known as the three-well problem. We present a new approach to finding inner and outer bounds. In Chapter 4, we focus on highly compatible, so called self-accommodating, martensitic structures and present new results on their fine properties such as estimates on their minimum complexity and bounds on the relative proportion of each martensitic variant in them. In Chapter 5, we investigate the contrary situation when self-accommodating microstructures do not exist. We determine, whether in this situation, it is still energetically favourable to nucleate martensite within austenite. By constructing different types of inclusions, we find that the optimal shape of an inclusion is flat and thin which is in agreement with experimental observation. In Chapter 6, we introduce a mechanism that identifies transformation strains with orientation relationships. This mechanism allows us to develop a simpler, strain-based approach to phase transformation models in steels. One novelty of this approach is the derivation of an explicit dependence of the orientation relationships on the ratio of tetragonality of the product phase. In Chapter 7, we establish a correspondence between common phenomenological models for steels and the Ball-James model. This correspondence is then used to develop a new theory for the (5 5 7) lath transformation in low-carbon steels. Compared to existing theories, this new approach requires a significantly smaller number of input parameters. Furthermore, it predicts a microstructure morphology which differs from what is conventionally believed.
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Teaching an AI to recycle by looking at scrap metal : Semantic segmentation through self-supervised learning with transformers / Lär en AI att källsortera genom att kolla på metallskrotForsberg, Edwin, Harris, Carl January 2022 (has links)
Stena Recycling is one of the leading recycling companies in Sweden and at their facility in Halmstad, 300 tonnes of refuse are handled every day where aluminium is one of the most valuable materials they sort. Today, most of the sorting process is done automatically, but there are still parts of the refuse that are not correctly sorted. Approximately 4\% of the aluminium is currently not properly sorted and goes to waste. Earlier works have investigated using machine vision to help in the sorting process at Stena Recycling. However, consistently through all these previous works, there is a problem in gathering enough annotated data to train the machine learning models. This thesis aims to investigate how machine vision could be used in the recycling process and if pre-training models using self-supervised learning can alleviate the problem of gathering annotated data and yield an improvement. The results show that machine vision models could viably be used in an information system to assist operators. This thesis also shows that pre-training models with self-supervised learning may yield a small increase in performance. Furthermore, we show that models pre-trained using self-supervised learning also appear to transfer the knowledge learned from images created in a lab environment to images taken at the recycling plant.
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Člověk s postižením v sourozeneckých konstelacích dvojčat a trojčat / Person with disability in sibling constellations of twins and tripletsKaletová, Magdalena January 2014 (has links)
THE ABSTRACT The thesis deals with sibling relationships of twins and triplets when one or more siblings suffer from some health disability or handicap. It outlines the way of life in sibling constellations of twins and triplets. It deals with the topic of a disabled person who has brothers or sisters. It defines family as a pillar of person's life and it focuses on the sibling relationships. The thesis explains the connection between multiple births and the occurrence of disability, and it considers certain aspects of family life, with the main focus on siblings, when one of the siblings suffers from some health limitation. It also describes twins and triplets and their specific features. For example, it shows the development of the identity of each of the siblings, the role of their birth order, the types of relationships that occur in a family with twins and triplets, and the way the siblings may experience the separation from one another. It draws on publications and other sources that deal with sibling constellations and the resulting relationships among the siblings, on the publications on twins and triplets, on children and adults with disability or handicap. Last not least, it draws on personal experience of the author and on the research interviews. Apart from that, the thesis clarifies how twins...
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Solidification dirigée du silicium multi-cristallin pour les applications photovoltaïques : caractérisation in situ et en temps réel par imagerie X synchrotron / Directional solidification of multi-crystalline silicon for photovoltaic applications : in-situ and real time characterisation by synchrotron X-ray imagingTandjaoui, Amina 17 October 2013 (has links)
Nous avons étudié in situ et en temps réel la structure de grains du silicium multi-cristallin issue de la solidification dirigée en utilisant l’imagerie X synchrotron. La radiographie X permet de suivre l’évolution de l’interface solide/liquide et de caractériser sa dynamique et sa morphologie. La topographie X nous donne des informations sur la structure de grains formée, les contraintes et les défauts issus de la solidification. Nous avons montré l’importance la préparation de l’état initial de la solidification en particulier pour les expériences de reprise sur germe. L’analyse de la morphologie de l’interface solide/liquide nous a permis de caractériser la surfusion cinétique du front de solidification, de comprendre l’évolution des sillons de joints de grains et d’analyser les mécanismes de compétition de grains ainsi que de révéler l’impact des impuretés sur la structure de grains formée à l’issue de la solidification. Le phénomène de maclage a aussi été observé dans nos expériences et nous avons démontré que les macles dans le silicium multi-cristallin peuvent être des macles de croissance. Deux types de macles ont été identifiés et le phénomène de compétition de grains en présence de macles étudié. / We studied in situ and real-time the grain structure of multi-crystalline silicon from directional solidification using synchrotron X-ray imaging techniques. X-ray Radiography gives information on the evolution, dynamics and morphology of the solid/liquid interface. X- ray Topography gives more information on the grain structure, strains and defects that occur during solidification step. We showed the importance of the preparation of the initial stage of solidification in particular in the experiments where solidification is initiated from seed. The analysis of the solid/liquid interface morphology allowed us to characterize the kinetic undercooling of the solidification front, to understand the evolution of the grains boundary grooves and to analyze the mechanisms of grain competition and also to reveal the impurities impact on the grain structure formed at the end of the solidification. We also observed twinning phenomenon in our experiments and we demonstrated that twins in multi-crystalline silicon can be growth twins. Two kinds of silicon twins have been identified and the grain competition phenomenon with twins studied.
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INFLUENCE OF IRRADIATION AND LASER WELDING ON DEFORMATION MECHANISMS IN AUSTENITIC STAINLESS STEELSKeyou Mao (6848774) 02 August 2019 (has links)
<p>
This dissertation describes the recent advancements in
micromechanical testing that inform how deformation mechanisms in austenitic stainless
steels (SS) are affected by the presence of irradiation-induced defects.
Austenitic SS is one of the most widely utilized structural alloys in nuclear
energy systems, but the role of irradiation on its underlying mechanisms of
mechanical deformation remains poorly understood. Now, recent advancement of
microscale mechanical testing in a scanning electron microscope (SEM), coupled
with site-specific transmission electron microscopy (TEM), enables us to
precisely determine deformation mechanisms as a function of plastic strain and
grain orientation.</p>
<p> </p>
<p>We focus on AISI 304L SSs irradiated in
EBR-II to ~1-28 displacements per atom (dpa) at ~415 °C and contains ~0.2-8
atomic parts per million (appm) He amounting to ~0.2-2.8% swelling. A portion
of the specimen is laser welded in a hot cell; the laser weld heat affected
zone (HAZ) is studied and considered to have undergone post-irradiation
annealing (PIA). An archival, virgin specimen is also studied as a control. We
conduct nanoindentation, then prepare TEM lamellae from the indent plastic
zone. In the 3 appm He condition, TEM investigation reveals nucleation of
deformation-induced <i>α</i>’ martensite in
the irradiated specimen, and metastable <i>ε</i>
martensite in the PIA specimen. Meanwhile, the unirradiated control specimen
exhibits evidence only of dislocation slip and twinning; this is unsurprising
given that alternative deformation mechanisms such as twinning and martensitic
transformation are typically observed only near cryogenic temperatures in
austenitic SS. Surface area of irradiation-produced cavities contribute enough
free energy to accommodate the martensitic transformation. The lower population
of cavities in the PIA material enables metastable <i>ε</i> martensite formation, while the higher cavity number density in
the irradiated material causes direct <i>α</i>’
martensite formation. In the 0.2 appm He condition, SEM-based micropillar
compression tests confirm nanoindentation results. A deformation transition map
with corresponding criteria has been proposed for tailoring the plasticity of irradiated
steels. Irradiation damage could enable fundamental, mechanistic studies of
deformation mechanisms that are typically only accessible at extremely low
temperatures. </p>
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Gestações gemelares com pesos discordantes: estudo da predição ultra-sonográfica e dos resultados neonatais / Twin growth discordance: sonographic prediction and factors related to perinatal outcomeMachado, Rita de Cassia Alam 01 November 2006 (has links)
A gemelaridade apresenta algumas intercorrências específicas, como a discordância de peso entre fetos e recém-nascidos (RNs). O objetivo do presente estudo foi predizer a discordância de peso do exame ultra-sonográfico comparada à do parto e avaliar a morbidade e a mortalidade neonatais nas gestações gemelares discordantes quanto ao peso. Este foi um estudo retrospectivo, com levantamento dos casos do período de 1998 a 2004, no Setor de Gestações Múltiplas da Clínica Obstétrica do HCFMUSP. Na avaliação da predição ultra-sonográfica, foram inseridas 221 gestações gemelares e, na avaliação da morbidade e da mortalidade, 151 gestações com partos nessa instituição. A discordância de peso foi definida como >= 20%, sendo excluídos os casos de malformações fetais (n=43) e da Síndrome da transfusão feto-fetal (n=24). Para análise da adequação do peso ao nascimento, utilizou-se a curva de Alexander et al., 1998, para gêmeos. No estudo da predição, foram utilizados quatro intervalos de tempo em relação ao parto (0 a 7 dias - n = 96; 8 a 14 dias - n = 66; 15 a 21 dias - n = 58; 22 a 28 dias - n = 59 gestações), somando 279 avaliações. No grupo de 0 a 7 dias, a estimativa da sensibilidade foi de 93,6%, especificidade de 79,4%, valor preditivo positivo de 89,2%, valor preditivo negativo de 87,1% e acurácia de 88,6%. Nos demais grupos, a sensibilidade e a acurácia foram de 95,8% e 84,9%, 95,6% e 84,5%, 90,9% e 84,8%, respectivamente. Em relação à morbidade, 111 gestações eram concordantes (73,5%) e 40 discordantes quanto ao peso. No grupo discordante, 75% das gestações gemelares apresentaram pelo menos um recém-nascido com Restrição de Crescimento Fetal (RCF). Nesta análise, as gestações gemelares concordantes monocoriônicas obtiveram menor média de idade gestacional no parto (34,3 versus 36,2 semanas, p=0,004), menor peso médio (2067 versus 2334 gramas, p=0,0016) e maior tempo de internação (10,6 versus 7,3 dias, p=0,0023) que as gestações concordantes dicoriônicas. Nas gestações discordantes, não houve diferença significativa em relação à corionicidade. As gestações discordantes, com pelo menos um RN abaixo do percentil 10, apresentaram menor média de idade gestacional (35,2 versus 36,8 semanas, p=0,009) e maior tempo de internação (17,5 versus 8,2 dias, p=0,026). Não foi observada diferença significativa de morbidade e mortalidade entre RNs concordantes e discordantes, com pesos entre os percentis 10 e 90. Os fetos menores das gestações discordantes demonstraram maior freqüência de índice de Apgar inferior a 7 (27,5% versus 7,5%, p=0,01). A avaliação da mortalidade não demonstrou diferença significativa em relação aos grupos concordantes (3,7%) e discordantes (4,5%; p = 1,00). No presente estudo, conclui-se que os quatro grupos apresentaram adequada correlação entre a discordância de peso à ultra-sonografia e no nascimento, porém com melhor predição até sete dias antes do parto. A morbidade neonatal esteve relacionada à RCF do menor feto. A discordância de peso e a corionicidade não interferiram na mortalidade neonatal. / The aim of this study was to evaluate the ability of prenatal ultrasound scans to predict fetal growth discordance in twin pregnancies and perinatal morbidity/mortality associated with these cases. This was a retrospective study (1998-2004) involving twin pregnancies that were scanned and had their delivery at our Institution (HCFMUSP). Cases with fetal malformations (n=43) or twin to twin transfusion syndrome (n=24) were excluded. The study of ultrasound scans consisted of 221 twin pregnancies. The final morbidity/mortality study group consisted of 151 twin pregnancies. Birth weight was evaluated based on twin growth charts published by Alexander et al (1998) and weight discordance as a difference >= 20%. Small for gestacional age (SGA) was defined as birth weight below the 10th centile. The study of ultrasonographic prediction of interwin discordance was made using four different intervals between ultrasound examination and delivery (0 to 7 days, n = 96; 8 to 14 days, n = 66; 15 to 21 days, n = 58; 22 to 28 days, n = 59 pregnancies), with a total of 279 ultrasound examinations. In group 0 to 7 days, the sensitivity was 93,6%, specificity was 79,4%, positive predicted values was 89,2%, negative predicted values was 87,1% and accuracy was 88,6%. In the groups 8 to 14 days, 15 to 21 days and 22 to 28 days the sensitivity and accuracy were 95,8% and 84,9%, 95,6% and 84,5%, 90,9% and 84,8%, respectively. Birthweight discordance was observed in 40 sets of twins (26.5%) and 12 cases were monochorionic MC (30%). Twenty five cases (22.5%) in the non discordant group were MC. In the non discordant group, monochorionic pregnancies showed lower gestational age at delivery (34.3 versus 36.2 wks, p=0.004), lower mean birth weight (2067g versus 2334g, p=0.0016) and longer length of stay in hospital (10.6 versus 7.3 days, p=0.0023) compared to dichorionic twins. In the group with twin birthweight discordance, there were no significant differences between MC and DC pregnancies and 75% of the cases had at least one newborn with SGA. These cases were showed lower gestational age at delivery (35.2 versus 36.8wks, p=0.009) and longer length of stay in hospital (17.5 versus 8.2 days, p=0.026). In the discordant group, the smaller twin had a higher frequency of first minute Apgar score < 7 (27.5% versus 7.5%, p=0.01). Perinatal mortality rate was similar in both groups (discordant 4.5% and concordant 3.7%, p=1.0). There were no significant differences in morbidity and mortality between concordant and discordant twins when birth weight was between the 10 th and 90 th centile. In conclusion, there was a good correlation between fetal growth discordance predicted by prenatal scan and actual birth weight discordance. Neonatal morbidity was related to SGA. Excluding fetal malformation and TTTS cases, birth weight discordance in twin pregnancies is not a significantly associated with neonatal mortality.
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Untersuchungen zum Einfluss der Fütterungsintensität während der Aufzucht auf Milchleistung und physiologische Kennwerte beim MilchrindMlaouhi, Amel 23 February 2011 (has links)
In einem Fütterungsversuch mit 15 weiblichen, genetisch identischen Zwillingspaaren wurde der anhaltende Effekt energetisch unterschiedlich konzentrierter Futterrationen auf Körper- und Blutmerkmale zwischen dem vierten und 21. Lebensmonat erfasst. Die gleichen Merkmale wurden an den Tieren auch während der Laktation erhoben, als die Tiere einheitlich gefüttert wurden. Zusätzlich wurde die Milchleistung untersucht. Während der Aufzucht wurden Körpergewicht, tägliche Gewichtszunahme, Rückenfettdicke und Widerristhöhe von der Fütterungsintensität signifikant beeinflusst. Körpergewicht und Rückenfettdicke zeigten vom siebenten bis 15. Lebensmonat die größten Unterschiede zwischen den Fütterungsgruppen. Im Gegensatz zum Körpergewicht, wurde der Fettansatz bis zum 21. Lebensmonat kaum gebremst. Für die Serumkonzentrationen von Insulin, Glukose und beta-Hydroybuttersäure und die Erythrozytenindizes MCV und MCH konnte ein signifikanter Fütterungseinfluss während der gesamten Aufzuchtphase nachgewiesen werden. Kortisol, Kreatinin, ASAT, GGT, GLDH, MCHC, Leukozytenzahl, Thrombozytenzahl reagierten auf den Fütterungsstimulus nur innerhalb bestimmter Altersabschnitte. Bis zum neunten Monat differierte der Insulinspiegel zwischen den Fütterungsgruppen kaum, ab dem 10. Lebensmonat aber sehr deutlich. Es kann daher ausgeschlossen werden, dass der Insulinspiegel im präpubertären Abschnitt die Entwicklung der späteren Milchleistung beeinflusste. Nach dem Abkalben war die intensiv gefütterte Gruppe stärkeren metabolischen Belastungen ausgesetzt und hatte eine geringere Milchleistung als die moderat gefütterte Gruppe. Offensichtlich wurde der Stoffwechsel durch die vorangegangene Fütterung geprägt, da der Fettansatz in der Intensivgruppe bei gleicher Fütterung früher einsetzte und auch intensiver erfolgte. Einige Kennwerte beim Jungtier korrelierten signifikant mit der späteren Milchleistung. Altersabhängige Veränderungen der Korrelationskoeffizienten weisen auf unterschiedlich sensible Phasen für die Prägung der späteren Milchleistung hin. / In a feeding trial with 15 pairs of genetically identical female twins, the effect of feeding intensity on body condition and blood parameters were investigated between the fourth and 21st month. The same traits were analysed on the cows during the first lactation when the animals were uniformly fed. In addition to these traits, the milk yield was investigated. During the rearing period; body weight, daily weight gain, back fat thickness, and withers height were significantly influenced by feeding. The largest differences between the feeding groups in body weight and back fat thickness were seen between the ages of seventh to 15th months. In contrast to body weight, back fat thickness hardly exceeded the 21st month between the groups. The serum concentrations of insulin, glucose, beta-Hydroxybutyric acid, and the erythrocyte indices MCV and MCH showed a significant feeding effect throughout the growing period. Cortisol, creatinine, Aspartate transaminase (AST), y-glutamyltransferase (GGT), Glutamate dehydrogenase (GDH), mean corpuscular hemoglobin concentration (MCHC), white blood cells (WBC) and platelet responded to the feeding stimulus only within certain ages. At age nine months, insulin levels were barely differed between the feeding groups but were distinct as from the 10th month. It can therefore be concluded that insulin levels at the pre-pubertal development affects the subsequent milk yield. After calving, the intensively fed group had more metabolic stress and had a lower milk yield than the moderately fed group. Obviously, the metabolism was programmed in the previous feeding period. There was an early onset and a more intensive fat deposition in the intensive group though; they had the same feeding level. Some traits in young animals were significantly correlated with subsequent milk yield. Age-dependent changes in the correlation coefficients suggest the fact that differences in sensible juvenile phases in traits could contribute to milk yield later.
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