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HEDLUNDH, SANDRA, and FRIDA NYBERG. "Development and implementation of 4D modeling in a Gigafactory." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299332.
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The auto manufacturing industry has experienced a shift towards a lower carbon trajectory, resulting in new fleets of electric vehicles. The trajectory has put the supply chain in motion and the demand for lithium-ion batteries has increased significantly. The expected growth within the energy storage industry has led to companies starting to produce lithium-ion batteries. The production facilities, called Gigafactories, involve a large number of international suppliers, highly complex process steps as well as strict environmental requirements. In Sweden, Northvolt has become a frontrunner for high-quality green batteries and has recently started to build its Gigafactory in Skellefteå. Northvolt has aimed to implement 4D modeling in the Gigafactory in Skellefteå. 4D modelling has been within the construction industry for about two decades. The technology within planning and 3D modelling has evolved further to generate more advanced simulations. 4D modeling has its core in pure construction processes and the research of using 4D modeling for production facilities is scarce. The purpose was to foresee potential problems in the construction process at an early stage to increase efficiency, while quality-checking the installation process. Furthermore, there is a research gap within using 4D modeling for automated, large-scale production facilities. For a Gigafactory, multiple aspects and departments need to be involved to define a 4D development process that will bring value to the organization. The implementation process for 4D modeling was designed for Northvolt’s Blueprint team, which is responsible for fast and cost-efficient scale-up for the production facilities with improvements in operations and project deliveries. The focus of the implementation process was primarily on developing 4D modeling for the installation of equipment but was required to allow scalability of other areas in the construction. The presented implementation process is defined by practically developing 4D modeling in a Gigafactory. The process was developed in several iterations to add value with identified attributes. In addition, the involved departments' ways of working were aligned, which improved communication and thereby minimized the challenge of having design and planning separated. When developing an implementation process for 4D modeling in a Gigafactory, established workflows and clear internal structures were needed. The main challenge of implementing 4D modeling is to automate the workflow to eliminate the risk of human errors. The result was a semiautomated process to manage the program's lack of interactions. An additional investigation was made to clarify that an automated process could be designed in-house for future 4D projects.<br>Bilindustrin har som mål att minska koldioxidutsläppen vilket har resulterat i ett ökat intresse för elektriska fordon. Detta har skapat förändringar i materialflöden med en ökad efterfrågan av litiumjonbatterier. Den ökade tillväxten inom energilagring har lett till att organisationer inlett produktion av litiumjonbatterier i stora anläggningarna, så kallade Gigafabriker. Dessa fabriker involverar flertalet internationella leverantörer, komplexa processer samt strikta miljöer med höga krav på renlighet och luftfuktighet. I Sverige har Northvolt blivit en ledare för dessa gröna batterier och började nyligen bygga en Gigafabrik i Skellefteå. Northvolt vill implementera 4D-modellering i Gigafabriken för att tidigt kunna förutse och åtgärda potentiella problem. Modellering i fyra dimensioner (4D) har funnits på marknaden i ungefär två årtionden, men det är först nu som tekniken finns på plats för att kunna skapa mer avancerade simuleringar. 4D-modellering har sin grund inom bygg- och konstruktionsindustrin, medan användandet i produktionsanläggningar är minimal. Att implementera 4D-modellering i Gigafabriken i Skellefteå skulle öka effektiviteten och samtidigt kvalitetssäkra installationsprocessen. Flera avdelningar behöver vara involverade för att utveckla 4Dmodellering som ger värde för organisationen. Vidare så saknas det forskning om att använda 4Dmodellering i automatiserade och storskaliga produktionsanläggningar. Implementeringsprocessen av 4D-modellering designades för Blueprint teamet på Northvolt. Teamet är ansvariga för snabba, skalbara och kostnadseffektiva produktionsanläggningar som förbättrar drift och projektleveranser. Syftet med studien var att utveckla implementeringsprocessen för 4D-modellering med fokus på installation av maskiner. Därutöver så behövde utvecklingsprocessen även vara skalbar för att inkludera andra områden i konstruktionen. Den presenterade implementeringsprocessen är framtagen genom att praktiskt utveckla 4Dmodellering i flera iterationer för att integrera värdet av de identifierade attributen. Genom att arbetsmetoderna anpassades för 4D-modellering kunde kommunikationen inom organisationen förbättras och därmed minska utmaningarna med separata avdelningar. När 4D-modellering ska implementeras måste arbetssätt och interna strukturer vara tydliga och väldefinierade. Den största utmaningen med att implementera 4D-modellering är att automatisera arbetsflödet för att minska risken för den mänskliga faktorn. Resultatet blev en semi-automatiserad process för att hantera programmens brist på interaktion. En ytterligare undersökning visade att en automatiserad process kunde utvecklas in-house för framtida 4D-projekt.
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Wright, Richard James. "4D seismic analysis of the Hibernia oil field, Grand Banks, Canada /." Internet access available to MUN users only:, 2004. http://collections.mun.ca/u?/theses,16342.
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Lin, Lan. "Development and clinical application of an integrated treatment planning platform for 4D radiotherapy : a dissertation /." San Antonio : UTHSC, 2007. http://proquest.umi.com/pqdweb?did=1400966621&sid=1&Fmt=2&clientId=70986&RQT=309&VName=PQD.
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Carabana, Garcia Claudia. "Defining cell fate specification of mouse Mammary Stem Cells in 4D." Electronic Thesis or Diss., Université Paris sciences et lettres, 2022. http://www.theses.fr/2022UPSLS055.
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SPÉCIFICATION DU DESTIN CELLULAIRE DES CELLULES SOUCHES MAMMAIRES EN 4DAu cours du développement, une coordination entre la spécification du destin cellulaire et la morphogenèse tissulaire est nécessaire à la formation des organes. Par conséquent, la façon dont différents types de cellules se différencient dans le temps et l'espace reste une question majeure en biologie du développement.La glande mammaire est constituée d'un épithélium ramifié composé d'une couche externe de cellules basales (BCs) et d'un compartiment interne de cellules luminales (LCs). Dans ce tissu, l'homéostasie adulte est exclusivement maintenue par des progéniteurs unipotents, alors que des cellules souches mammaires multipotentes (MaSC) ne se trouvent que dans la glande embryonnaire, ce qui en fait un paradigme tissulaire idéal pour étudier leur comportement dynamique et leur contribution à la morphogenèse tissulaire.HYPOTHÈSE DE TRAVAILNous avons récemment montré que les cellules souches mammaires deviennent unipotentes lors de la tubulogenèse de la glande, suggérant un lien étroit entre spécification cellulaire et morphogenèse. Notre hypothèse implique que la perte de multipotence soit liée aux remaniements cellulaires qui guident la morphogenèse. Cependant, le moment exact et les mécanismes responsables du passage de la multipotence à l'unipotence sont encore inconnus.OBJECTIF ET MÉTHODOLOGIEL'objectif principal de ce projet était d'intégrer les circuits transcriptionnels définissant le potentiel de différenciation des cellules souches à l'analyse de la morphogenèse cellulaire et tissulaire en temps réel, afin de déchiffrer les mécanismes qui sous-tendent l'acquisition de l'identité cellulaire et d'étudier la coordination entre spécification des cellules souches et morphogenèse. Nous avons abordé cet objectif ambitieux en combinant deux approches : 1) des analyses transcriptomiques en cellule unique intégrées dans l’espace, au cours du développement mammaire, et 2) une approche de suivi du lignage en temps réel dans des cultures mammaires embryonnaires ex vivo, afin d'étudier les comportements et réarrangements cellulaires au cours des premières phases de la croissance mammaire.RÉSULTATSNous avons constaté que la restriction du potentiel des cellules souches est progressive pendant le développement embryonnaire. Par transcriptomique sur cellules uniques, nous avons pu distinguer trois types cellulaires distincts très tôt (E15). L'intégration dans l’espace de ces données transcriptomiques nous a révélé que des cellules de type BC et LC sont positionnées différemment dans le bourgeon mammaire très précocement. Cette analyse a donc révélé de nouveaux marqueurs moléculaires des LC et BC embryonnaires, qui ne peuvent pas être distingués avec les marqueurs mammaires adultes connus.De plus, nous avons défini les signatures transcriptionnelles qui distinguent deux populations de cellules stromales mammaires embryonnaires délimitées dans l'espace. Nous avons aussi montré qu’une signalisation paracrine du mésenchyme aux cellules épithéliales, via Fgf10-Fgfr2, influence la morphogenèse de la glande mammaire.Nous avons ensuite développé une approche d’analyse d’images semi-automatique aux niveaux cellulaire et tissulaire dans nos explants mammaires analysés par microscopie time-lapse. Nous montrons que les étapes initiales de la morphogenèse sont caractérisées par des réarrangements cellulaires très dynamiques. De plus, l'activation épithéliale de la beta-catenin empêche la formation de branches, indiquant que Wnt est un régulateur essentiel de la morphogenèse mammaire.Ces travaux mettent en lumière les circuits transcriptionnels qui régissent le branchement mammaire et qui lient la différenciation des cellules souches à leur dynamique cellulaire pendant la morphogenèse. Les mécanismes ainsi dévoilés nous fournissent des biomarqueurs potentiels du cancer du sein, qui résulte souvent de la réactivation de programmes de multipotence embryonnaires<br>DEFINING CELL FATE SPECIFICATION OF MOUSE MAMMARY STEM CELLS IN 4DCoordination of cell fate specification and branching morphogenesis is necessary to generate an organ with its specialized final structure and function. Accordingly, how different cell types are specified in a tightly regulated manner in time and space, in order to drive the morphogenesis of a complex tissue, remains a major question in the field of developmental biology.The mammary gland (MG) consists in a branched bi-layered epithelium composed of an outer layer of basal cells (BCs) and an inner compartment of polarised luminal cells (LCs). In this tissue, adult homeostasis is exclusively maintained by lineage-restricted unipotent progenitors, whereas multipotent mammary stem cells (MaSCs) are only found in the embryonic gland, making it an ideal tissue paradigm to study stem cell dynamics and lineage specification, as well as their contribution to tissue morphogenesis.WORKING HYPOTHESISOur recent results showed that multipotent MaSCs become lineage-restricted around embryonic day E15.5, coinciding with the first morphogenetic events that establish the mammary ductal network. We thus hypothesized that loss of multipotency in the mammary gland was linked to cell rearrangements, leading to the branching of embryonic mammary buds. However, the exact timing and the mechanisms responsible for the switch from multipotency to unipotency during embryonic MG are still unknown.AIM AND METHODOLOGYThe overarching aim of this project was to characterise the stem cell dynamics underlying MaSCs differentiation during MG development, and to define the transcriptional signals underpinning this process. We have approached this ambitious objective combining two approaches: 1) single-cell RNA sequencing analysis at different embryonic times, to discover which signals determine cell identity during mammary development, and 2) a live lineage tracing approach in ex vivo embryonic mammary cultures to study dynamic cell behaviours and rearrangements during the earliest phases of mammary growth.RESULTSWe found that lineage restriction is a progressive developmental process. By single cell transcriptomics, we identified a single population of mammary epithelial cells at E13.5, but we could distinguish three transcriptionally distinct cell subsets at E15.5, which included luminal-like, basal-like and hybrid cells co-expressing luminal and basal genes. Spatial transcriptomic analysis revealed that the basal-like and luminal-like clusters were indeed already spatially restricted in the embryonic mammary bud, being positioned either in close proximity to the basement membrane or in the inner bud region, respectively. Importantly, this analysis revealed novel molecular markers of committing LCs and BCs, that cannot be distinguished with known adult MG markers.Additionally, we report the transcriptional signatures distinguishing two spatially restricted embryonic mammary mesenchymal cell populations, representing sub-epithelial and dermal mesenchyme. Long-term live-imaging revealed that paracrine signalling from embryonic mesenchyme to epithelial cells, via Fgf10-Fgfr2, influences epithelial branching.We then developed a deep learning-based pipeline to semi-automatically track individual cells and tissue branches in embryonic mammary explants analysed by time-lapse microscopy. We show that the initial steps of morphogenesis are characterized by highly dynamic cell rearrangements in the growing branch tips. However, forced activation of the Wnt/b-catenin pathway in the embryonic mammary epithelium precluded branching in vivo and ex vivo, indicating that epithelial Wnt signalling is an essential regulator of mammary branching morphogenesis.This work sheds light on the timing and mechanisms governing mammary cell fate decisions, providing potential biomarkers of breast cancer, which often arises from reactivation of embryonic multipotency programs
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Kunieda, Yoichiro. "Development of an impact assessment tool for demolition." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.715294.
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Currently in the field of demolition, which generates most of the waste in the construction industry, the treatment of waste largely relies on landfill or degraded recycling, which leads to significant consumption of natural resource and energy and a shortage of landfill site. In order to improve the inefficiency of demolition waste recovery, “to suggest improvements in the environmental impact of the demolition industry in UK” was set as the aim of the present research. After the identification of few opportunities for communication between demolishers and constructers in the current social system, a collaboration support system between these two stakeholders called ‘Demolition Project Mapping’ (DPM) system was suggested. In the system, the impact evaluation tool developed in the 4D-CAD software is applied to the demolition project simulation. This tool allows the users to dynamically simulate the impact of project planning which can be designed in the tool. In the pilot study, the simulation result shows the large potential to reduce the impact (e.g. 28% for the cost) by the tool application.
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Bock, Jelena [Verfasser], and Hans [Akademischer Betreuer] Burkhardt. "Development and testing of new strategies for pre-processing and analysis of 4D flow-senisitive mri data = Entwicklung und Erprobung neuer Strategien zur Bearbeitung und Analyse von 4D flusssensitiven MR Daten." Freiburg : Universität, 2013. http://d-nb.info/1123475733/34.
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Thomas, Rowena. "Development of resonant inelastic X-ray metal catalysts scattering spectroscopy for 4d and 5d transition metal catalysts." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/354566/.
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Feng, Yan. "Development and implementation of quadratically distorted (QD) grating and grisms system for 4D multi-colour microscopy imaging (MCMI)." Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3190.
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The recent emergence of super-resolution microscopy imaging techniques has surpassed the diffraction limit to improve image resolution. Contrary to the breakthroughs of spatial resolution, high temporal resolution remains a challenge. This dissertation demonstrates a simple, on axis, 4D (3D + time) multi-colour microscopy imaging (MCMI) technology that delivers simultaneous 3D broadband imaging over cellular volumes, which is especially applicable to the real-time imaging of fast moving biospecimens. Quadratically distorted (QD) grating, in the form of an off axis-Fresnel zone plate, images multiple object planes simultaneously on a single image plane. A delicate mathematical model of 2D QD grating has been established and implemented in the design and optimization of QD grating. Grism, a blazed grating and prism combination, achieves chromatic control in the 4D multi-plane imaging. A pair of grisms, whose separation can be varied, provide a collimated beam with a tuneable chromatic shear from a collimated polychromatic input. The optical system based on QD grating and grisms has been simply appended to the camera port of a commercial microscope, and a few bioimaging tests have been performed, i.e. the 4D chromatically corrected imaging of fluorescence microspheres, MCF-7 and HeLa cells. Further investigation of bioimaging problems is still in progress.
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Morton, Natasha Elizabeth. "Improving thoracic imaging for radiation therapy: The development and translation of patient adaptive computed tomography." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28950.
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Radiotherapy is a lifesaving cancer treatment using radiation to kill cancer cells. Effective treatment requires accuracy and precision, directing radiation to the cancer while avoiding healthy tissue. As such, in-depth knowledge of the cancer’s size, location and surroundings is required for planning radiation delivery. For regions under motion, such as the thorax, spatial-temporal imaging (4D CT) is required to gain an understanding of how the anatomy will move during treatment. Current 4D CT techniques fail to adapt to a changing patient, resulting in inaccurate images and reduced confidence in treatment planning.
This thesis presents the development and implementation of the next generation of 4D CT, patient adaptive CT imaging. Adaptive CT is a software solution that adapts the 4D CT imaging process to patient motion signals (respiratory changes and cardiac function), with the goal of improving image accuracy.
There are three main studies around which this body of work focuses. The first outlines steps towards the clinical translation of adaptive CT, comparing adaptive CT to standard 4D CT imaging techniques.
The second outlines the development for future applications and improvements of adaptive CT. Delving into limitations of the system itself, an in-silico analysis of the system and scanner parameters on image quality is detailed. The universality of the system is discussed and techniques for inter-brand compatibility are explored.
The third details the expansion of adaptive CT for emerging radiation therapy indications. Cardiac motion is incorporated into the adaptive CT software and a detailed feasibility study is presented with implications for centrally located lung cancer and non-invasive cardiac radioablation treatments.
Overall, this body of work presents the advancement of patient adaptive CT imaging, providing superior images for radiation therapy treatment planning and opening up 4D CT imaging for new treatment paradigms.
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Silva, Pedro Emanuel Santos. "Development of new structures with helical filaments." Doctoral thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/22960.
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Doutoramento em Nanociências e Nanotecnologia<br>O entrelaçamento de estruturas filamentares marcou um passo importante
na evolução da humanidade. Vários tipos de filamentos são usados
em tecidos, cordas e, mais recentemente em micro e nanoestruturas.
Esta tese oferece um contributo que pode ser relevante para as àreas
do têxtil, nanotecnologias e campos relacionados com a ciência dos
materiais.
Nesta tese, são descritos métodos para produzir micro e nanofibras com
diferentes propriedades físicas de acordo com formatos pré-estabelecidos
nas estruturas. Alguns destes métodos são inspirados em sistemas naturais,
onde as estruturas contêm topologias específicas para ultrapassar
diferentes tarefas. Em particular, fibras helicoidais são produzidas experimentalmente
usando a técnica de electrofiação. Em segundo lugar, é
introduzido uma generalização do conceito das perversões. Perversões
são ocorrências geométricas que invertem o sentido de rotação de estruturas
helicoidais. As perversões aparecem quando filamentos, com as
extremidades constrangidas, enrolam e adoptam formas helicoidal mas
têm de conservar a torção total. Mostramos que é possível obter matematicamente
e experimentalmente uma variedade contínua de perversões
diferentes que apresentam diferentes geometrias. Experimentalmente,
diferentes perversões são geradas irradiando microfibras electrofiadas
com ciclos de irradiação de luz UV e máscaras opacas. Os resultados
experimentais confirmam também que os diferentes tipos de perversões
têm comportamentos distintos quando libertadas e adoptam configurações
finais diferentes. Do mesmo modo, usando uma abordagem
experimental semelhante, são obtidas hélices com diferentes curvaturas
alternadamente. É observado que, durante o relaxamento das fibras, as
regiões com curvatura intrínseca maior, começam a enrolar primeiro,
enquanto as regiões com curvatura intrínseca menor permanecem alongadas
até a um ponto em que começam a enrolar depois. Todos os
efeitos observados experimentalmente estão em concordância com simulações
computacionais realizadas para modelar a dinâmica de filamentos
com curvatura intrínseca. Os resultados experimentais e computacionais
demonstram que é possível controlar com precisão a forma de microfilamentos
modificando as propriedades mecânicas da superfície das fibras,
em vez de depender arranjos moleculares específicos. Por último, descrevemos duas abordagens para obter entrelaçamentos
com fibras helicoidais usando exclusivamente interacções mecânicas. A
ligação nos tecidos é gerada, no primeiro caso, fazendo enrolar as perversões
entre os filamentos adjacentes e, no segundo caso, entrelaçando as
voltas das hélices dos filamentos. Simulações computacionais mostram
como tecidos podem ser gerados com sucesso usando cada uma das
ideias para criar ligações entre as fibras.<br>The entanglement of filamentary structures marked an important step
in mankind evolution. Filaments appear in fabrics, ropes and, more
recently, in micro and nanostructures. This thesis offers a contribution
that can be relevant to the fields of textiles, nanotechnologies and
materials science in general.
In this thesis, we present methods for shaping micro and nanofibres on
demand and with different physical properties. Some of these methods
are inspired in natural systems, where structures have specific topologies
to fulfil different tasks. In particular, it will be discussed how fibres with
helical shape can be produced using the electrospinning technique.
Secondly, we introduce a generalization of the concept of perversions.
Perversions are geometrical occurrences that reverse the handedness
of connected helices. Perversions arise when clamped filaments coil
into a helical shape but must conserve zero overall twist. We show
mathematically and experimentally that a continuous range of different
perversions can exist and present different geometries. Experimentally,
different perversions are generated by using irradiated micro electrospun
fibres with cycles of UV light and opaque masks. Experimental results
also confirm that different types of perversions behave differently upon
release and adopt different final configurations. We also produce
filaments containing helices with alternating curvatures. It is observed
that, upon release, the regions with higher curvature start to curl
first, while regions with lower intrinsic curvature remain stretched until
start to curl later. All the effects observed in experiments is in good
agreement with computational simulations performed to model the
dynamics of filaments with intrinsic curvature. The experimental and
computational results showed that the precise control of the shape of
microfilaments can be achieved by changing the properties of the fibres
surface, instead of relying on material’s molecular arrangements.
Finally, we describe two approaches to entangle helical filaments by using
exclusively mechanical interactions. The linkage in fabrics is generated,
in the first case, by winding perversions between neighbouring filaments
and, in the second case, by intertwining helical loops of the filaments.
Computational simulations show how fabrics can be generated by using
both approaches to create links between the fibres.
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suh, yelin. "DEVELOPMENT AND INVESTIGATION OF INTENSITY-MODULATED RADIATION THERAPY TREATMENT PLANNING FOR FOUR-DIMENSIONAL ANATOMY." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1827.
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Lung cancer is the leading cause of cancer-related deaths worldwide. Radiotherapy is one of the main treatment modalities of lung cancer. However, the achievable accuracy of radiotherapy treatment is limited for lung-based tumors due to respiratory motion. Four-dimensional radiotherapy explicitly accounts for anatomic motion by characterizing the motion, creating a treatment plan that accounts for this motion, and delivering this plan to the moving anatomy. This thesis focuses on the current problems and solutions throughout the course of four-dimensional radiotherapy. For characterization of respiratory-induced motion, patient tumor motion data were analyzed. It is shown that tumor motion can be significant during radiotherapy treatment, and its extent, direction, and linearity vary considerably between patients, between treatment fractions, and between respiratory cycles. After this, approaches to four-dimensional intensity-modulated radiation therapy treatment planning were developed and investigated. Among the techniques to manage respiratory motion, tumor tracking using a dynamic multileaf collimator delivery technique was chosen as a promising method. A formalism to solve a general four-dimensional intensity-modulated radiation therapy treatment-planning problem was developed. Specific solutions to this problem accounting for tumor motion initially in one dimension and extending this to three dimensions were developed and investigated using four-dimensional computed tomography planning scans of lung cancer patients. For four-dimensional radiotherapy treatment delivery, accuracy of two-dimensional projection imaging methods was investigated. Geometric uncertainty due to the limitation of two-dimensional imaging in monitoring three-dimensional tumor motion during treatment delivery was quantified. This geometric uncertainty can be used to estimate proper margins when a single two-dimensional projection imager is used for four-dimensional treatment delivery. Lastly, tumor-tracking delivery using a moving average algorithm was investigated as an alternative delivery technique that reduces mechanical motion constraints of a multileaf collimator. Moving average tracking provides an approximate solution that can be immediately implemented for delivery of four-dimensional intensity-modulated radiation therapy treatment. The clinical implementation of four-dimensional guidance, intensity-modulated radiation therapy treatment planning, and dynamic multileaf collimator tracking delivery may have a positive impact on the treatment of lung cancer.
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Soldati, Enrico. "Development of a new approach for the assessment of complex blood flow patterns in the left atrium from 4D flow MRI imaging." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Mitral valve regurgitation is a common disorder affecting 2-3% of the general population. The morphological and functional remodelling of the left atrium caused by this disease could favour blood stagnation and consequently stroke risk. Several clinical studies suggest that stroke risk stratification may be improved by using hemodynamic information on the left atrium. The goal of this study was therefore to develop a new approach for the assessment of complex blood flow patterns in the left atrium which could quantify the hemodynamic implications of the mitral valve regurgitation on sick patients compared to healthy volunteers. This analysis may enable optimized patient risk stratification and therapy.
4D Flow MRI imaging on the subjects provides information of the anatomy and the velocity field in the three directions in space and time for all the acquisitions. We selected three time frames: the S, E and A wave corresponding to the reservoir, conduit and boosting pump function of the atrium, respectively. We derived the patient- specific anatomical model of the left atrium, by applying a Chan-Vese segmentation, furthermore, we derived the modulus of the velocities and calculated the vorticity performing the curl of the velocities field. We individuated and implemented four different criteria for the identification of vortex cores inside the left atrium, ω, Δ, Q and λ_2 criterion. We evaluated the N_k number defined as the quality of rotation of a vortex core and we proposed a scale to quantitatively quantify them. We also calculated other different features as kinetic energy, pressure gradient and Fourier transformation.
In this preliminary testing, the interface and the method proposed, returned a good segmentation and velocities in the expected range. All the features and methods proposed seem to indicate that a reduced blood washout in the left atrium occurs in sick patients, which might facilitate clot formation and increase of the thromboembolic risk.
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Thetpraphi, Kritsadi. "Development of electroactive polymer actuators for next generation mirror : Live-Mirror." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI058.
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Nous avons développé une technologie nouvelle et interdisciplinaire pour créer des systèmes optiques à base de métamatériaux extrêmement légers, limités par la diffraction, avec une qualité optique exceptionnelle et un coût et un temps de production spectaculairement inférieurs : Live-Mirror. La nouveauté est de remplacer les miroirs optiques rigides et lourds classiques par des systèmes optoélectroniques dynamiques « vivants » et légers constitués d'une fine feuille de verre optique activement soutenue par plusieurs actionneurs / capteurs de force intégrés et miniaturisés via la fabrication additive et l'impression 3D. Nos fonctionnalités révolutionnaires Live-Mirror et le contrôle actif de la forme avec des actionneurs de force à plusieurs degrés de liberté obtenus en développant une technologie additive basée sur l'impression 3D pour appliquer un système optimisé de polymère électroactif (EAP) à un sandwich de surfaces de verre minces, ainsi créant un nouveau métamatériau hybride avec des propriétés de rapport rigidité / densité supérieures. Cette thèse décrit le développement d'actionneurs souples à base d'EAP modifiés / dopés, ici appelés terpolymère P (VDF-TrFE-CFE). Nous montrerons que cette nouvelle matrice de terpolymère personnalisée Live-Mirror présente une propriété de couplage électromécanique exceptionnelle, en particulier lorsqu'elle est dopée avec un plastifiant, par ex. phtalate de diisononyle (DINP). Ici, nous démontrons qu'en optimisant la conception multicouche structurée, le couplage électromécanique du terpolymère modifié peut être amélioré, offrant une permittivité diélectrique élevée, un module d'Young faible et une rigidité diélectrique exceptionnelle. Cela conduit à une réponse de déformation importante ainsi qu'à une densité d'énergie mécanique élevée sous des champs électriques relativement faibles selon le phénomène d'électrostriction - l'objectif principal des spécifications de haut niveau de Live-Mirror. En plus d'une matrice de terpolymère personnalisée, le concept de multicouches empilées est démontré comme une technique simple et efficace pour augmenter les capacités d'actionnement. Plusieurs résultats expérimentaux de preuve de concept imprimés en 3D (en laboratoire), qui sont en bon accord avec les modèles numériques, valident les performances de l'actionneur avec une grande réponse électromécanique. Cette technologie montre la faisabilité d'un contrôle actif de la forme de la surface optique et montre le contrôle et la correction de la forme optique Live-Mirror avec seulement quelques degrés de liberté. Une telle application d'actionneur novatrice et avancée via une technologie de fabrication additive est compatible avec les télescopes d'astronomie et de communication basés au sol et dans l'espace ainsi que de nombreux appareils électroniques modernes<br>We have developed new and interdisciplinary technology for creating extremely lightweight, diffraction-limited, meta-material-based optical systems with exceptional optical quality and spectacularly lower cost and production time: Live-Mirror. The novelty is to replace classical rigid and heavy optical mirrors with “live” and light dynamic optoelectronic systems consisting of a thin optical glass sheet actively supported by multiple force-actuators/sensors integrated and miniaturized via additive manufacturing and 3D printing. Our breakthrough Live-Mirror features and active shape control with many-degrees-of-freedom force actuators achieved by developing an additive 3D-printing-based technology to apply an optimized electroactive polymer (EAP) systems to a sandwich of thin glass surfaces, thus creating a novel hybrid meta-material with superior stiffness-to-density ratio properties. This thesis describes the development of soft actuators based on modified/doped EAPs, here dubbed terpolymer P(VDF-TrFE-CFE). We will show that this new and Live-Mirror customized terpolymer matrix features an outstanding electromechanical coupling property, particularly when doped with a plasticizer, e.g. diisononyl phthalate (DINP). Here we demonstrate that by optimizing the structured multilayer design, the electromechanical coupling of the modified terpolymer can be enhanced, yielding high dielectric permittivity, low Young modulus, and exceptional dielectric strength. This leads to a large strain response as well as high mechanical energy density under relatively low electric fields according to the electrostriction phenomenon – the main goal of the high-level specifications of Live-Mirror. In addition to a customized terpolymer matrix, the concept of stacked multilayers is demonstrated as a simple and effective technique to boost actuation abilities. Several 3D-printed, proof-of-concept (in the lab) experimental results, which are in good agreement with numerical models, validate the actuator performance with a large electromechanical response. This technology shows feasibility for active optical surface shape control and demonstrates the Live-Mirror optical shape control and correction with only a few degrees-of-freedoms. Such a novel and advanced actuator application via additive manufacturing technology are compliant for ground- and space-based astronomy and communications telescopes as well as many modern electronic devices
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Cardiet, Colleen. "Développement méthodologique en IRM cardio-thoracique chez le petit animal." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0283.
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L’Imagerie cardio-thoracique par Résonance Magnétique est encore aujourd’hui un véritable défi. La difficulté réside dans la nécessité d’acquérir des images avec de fortes résolutions spatiales et temporelles sur des zones en mouvement, et ce, en un temps limité. Dans le but de s’affranchir des mouvements cardio-respiratoires, la solution la plus communément employée consiste à ne pas acquérir de données pendant l’inspiration et l’expiration ou à les écarter. Cette solution est aujourd’hui la plus communément appliquée, mais elle entraine une augmentation significative du temps d’acquisition total (jusqu’à 50%). Au vu de ces principales limitations, le travail mené au cours de cette thèse possède un objectif général : réduire les temps d’acquisition d’images cardio-thoraciques chez le petit animal et améliorer leur qualité (précision, contraste et résolution). Des séquences IRM radiale et à temps d’écho ultra-court (UTE) ainsi que des algorithmes de reconstruction ont été développés, pour obtenir des images cardio-thoraciques en 4D (3D-temporel) dans des temps d’acquisition court.Ce travail de recherche a été structuré autour de deux axes principaux.I - Développer une méthode d’interpolation des données cardiaques pendant les intervalles de mouvement respiratoire. Pour la première fois sur le petit animal, l’impact du mouvement respiratoire de la souris sur la position de son cœur a été précisément analysé. Un algorithme a ensuite été développé afin d’interpoler les données cardiaques pendant les intervalles de respiration. De manière novatrice, la reconstruction d’images cardiaques en fonction des battements du cœur utilisant la totalité des données acquises a été rendue possible. Ce protocole, intégré à la séquence UTE, a été testé, validé et comparé aux méthodes standards sur des souris saines puis il a été appliqué sur des pathologies cardio-pulmonaires à travers différentes collaborations. En conclusion, des images 4D du cœur battant de souris ont pu être acquises en 1’45 avec de fortes résolutions spatiale et temporelle (176m isotropique et 5ms / image), permettant de mesurer les paramètres cardiaques nécessaires à la détection, l’analyse ainsi que le suivi de différentes pathologies.II – Réduire le temps d’acquisition de l’imagerie cardio-thoracique 4D et améliorer son contraste : Application à l’angiographie pulmonaire. Une séquence Radiale 3D avec auto-synchronisation des mouvements a été développée avec les mêmes paramètres que l’UTE, afin de réduire davantage son temps d’acquisition. Les deux séquences ont été appliquées sur les poumons afin de reconstruire des angiographies pulmonaires 3D de haute résolution en fonction de la respiration. Une technique de suppression de graisse accélérée a été implémentée et permet d’améliorer le contraste entre les vaisseaux et les bronches, tout en maintenant une durée d’acquisition raisonnable. En conclusion, ces travaux ont permis d’optimiser les séquences UTE et Radiale et d’évaluer leur avantage en angiographie pulmonaire. Les résultats sont prometteurs et ouvrent des perspectives concernant la segmentation et la quantification du réseau vasculaire pulmonaire.En conclusion, les séquences et algorithmes développés au cours de ce projet ont permis de réduire considérablement les temps d’acquisitions d’imagerie cardio-thoracique 4D et ouvrent de ce fait des perspectives pour l’étude de modèles animaux ou pour un transfert en imagerie clinique.Mots clés : IRM ; Cardio-thoracique ; 4D ; Séquence ; Développement<br>Cardio-thoracic Magnetic Resonance Imaging is still a real challenge today. The difficulty stands in the need to acquire images with high spatial and temporal resolutions on moving areas, and in a limited time. In order to overcome cardio-respiratory motion, the most common solution is to not acquire data during inhalation and exhalation or to discard them. This solution is the most commonly used today, but it results in a significant increase in the total acquisition time (up to 50%). In view of these main limitations, the work carried out during this PhD training had the objectives to reduce the acquisition times of cardio-thoracic images in small animals and to improve their quality (precision, contrast and resolution). Radial and ultra-short echo time (UTE) MRI sequences as well as reconstruction algorithms were developed to obtain 4D (3D-temporal) cardio-thoracic images in short acquisition times.This research work was structured around two main axes.I - Develop a method of cardiac data interpolation during respiratory movement intervals. For the first time in small animals, the impact of the mouse's respiratory movement on the position of its heart has been precisely analyzed. An algorithm was then developed to interpolate cardiac data during breathing intervals. In a novel way, reconstruction of heart images based on heartbeat using all of the acquired data was made possible. This protocol, integrated into the UTE sequence, was tested, validated and compared to standard methods on healthy mice, then was applied to cardiopulmonary pathologies through various collaborations. In conclusion, 4D images of the mouse beating heart could be acquired in 1min45s with high spatial and temporal resolutions (176m isotropic and 5ms / image), enabling to measure the cardiac parameters necessary for the detection, analysis and monitoring of various pathologies.II - Reducing the acquisition time of 4D cardio-thoracic imaging and improving its contrast: Application to pulmonary angiography. A 3D Radial sequence with auto-synchronization to?/on? movements was developed with the same parameters as the UTE sequence, in order to further reduce acquisition time. The two sequences were applied on the lungs in order to reconstruct high resolution 3D pulmonary angiograms along the respiration. An accelerated fat saturation technique was implemented to improve the contrast between vessels and bronchi, while maintaining a reasonable acquisition time. In conclusion, this work enabled to optimize the UTE and Radial sequences and to evaluate their advantages in pulmonary angiography. The results are promising and open perspectives concerning the segmentation and quantification of the pulmonary vascular network.In conclusion, the sequences and algorithms developed during this project enabled to considerably reduce the acquisition times of 4D cardio-thoracic imaging and therefore open up perspectives for the study of animal models or for a transfer to clinical imaging.Keywords: MRI ; Cardio-thoracic ; 4D ; Sequence ; Development
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Collaudin, Samuel. "Exploration de l'origine de la robustesse de la dynamique d'expression d'AGAMOUS pendant le développement de la fleur en utilisant une approche pluridisciplinaire." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEN049/document.
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L'identité des organes floraux est définie par l’expression de gènes homéotiques appartenant à la famille des MADS-box au début du développement floral. Un de ces gènes, AGAMOUS (AG), est responsable de l’identité des étamines et des carpelles chez Arabidopsis thaliana. Dans ce manuscrit, je tente de comprendre les propriétés spatiales et temporelles de l’expression d’AG en cherchant à connaître les mécanismes impliqués dans le bon établissement de la dynamique d’expression d’AG pendant les jeunes stades du développement floral.Je débute par développer un modèle de réaction-diffusion qui prend en compte la croissance de la fleur pendant les stades d’intérêt, ainsi que quelques facteurs de transcriptions clefs impliqués dans la régulation d’AG. Ensuite j’ai imagé en direct et en 4D la croissance des fleurs pour quantifier l’activation de l’expression d’AG de son initiation à son patron d’expression stable. Je montre que son expression se déroule en deux phases: une phase de faible expression, et une phase de forte expression. Bien que toutes les cellules du dôme central de la fleur présentent un profil d’activation d’AG similaire, le temps précis au cours du développement où AG est activé est différent pour chacunes d’entre elles et est à l’origine de la stochasticité du patron d’expression. Avec l’aide du modèle, je propose quatres nouvelles hypothèses relatives à la régulation d’AG :AG est capable de maintenir sa propre activation en se liant directement à son second intron au travers d’un complexe protéique contenant au moins deux molécule d'AG, créant ainsi un seuil d'auto-activation.AP2 influence la valeur de ce seuil, restreint l’expression d’AG dans le dôme central de la fleur et produit un retard dans l’activation complète d’AG.LFY et WUS sont nécessaire à l’accumulation des protéines d’AG dans les cellules pour pouvoir atteindre le seuil d’auto-activation et obtenir une expression complète d’AG.Le mouvement d’AG est nécessaire pour obtenir l’expression d’AG dans toutes les cellules du dôme central. Pour prouver ces hypothèses, j’ai réalisé différentes expériences. En premier, utilisant une expérience de FRET-FLIM dans les protoplastes, nous proposons qu’AG est capable de s’associer en homodimer dans les cellules végétales. Néanmoins, sur-exprimer AG pour aider les cellules à atteindre le seuil d’auto-activation plus tôt que dans la plante sauvage ne semble pas modifier la dynamique d’expression de l’AG endogène. En deuxième, j’ai testé le rôle précis de LFY au cours des différentes phases et transitions de la dynamique d’expression d’AG en mutant les sites d'interactions spécifiques pour LFY au sein des séquences de régulation d’AG. Ces mutations retardent l’expression l’expression d’AG et modifient légèrement son patron d’expression. Je montre que seulement d’important retards dans l’activation d’AG induit des modifications phénotypiques. Ensuite, pour tester le rôle de la répression par AP2 dans la dynamique d’expression d’AG, j’analyse le rapporteur d’AG dans le contexte d’un mutant fort d’ap2. Dans ce mutant, l’expression d’AG s’étend à une région plus large et le retard entre l’initiation de l’expression d’AG et la transition entre les phases de faible et forte expressions est diminué. Ces résultats correspondent aux simulations du modèle. Finalement, pour comprendre l’importance du mouvement d’AG d’une cellule à l’autre dans sa propre dynamique, je bloque cette capacité de bouger en utilisant un tag de localisation nucléaire. Bien que cela induit un retard dans l’activation de quelques cellules au stade 3 au moment où toutes les cellules du dôme centrale de la fleur expriment AG dans la plante sauvage, ce retard n’a pas d’effets visible sur le phénotype<br>The identity of flower organs is defined by the expression of homeotic genes during early development that belongs to the MADS-box family. One of these genes, AGAMOUS (AG), is responsible for the identity of the stamens and the carpels in Arabidopsis thaliana. In this manuscript, I attempt to fully understand the spatial and temporal properties of AG expression by investigating the mechanisms underlying the proper establishment of AG expression dynamics during the early stages of flower development. I start by developing a reaction-diffusion model that takes into account the growth of the flower at the relevant stages, as well as the few key transcription factors involved in AG regulation. Next I used real-time 4D imaging on growing flowers to quantify the activation of AG expression from its onset to the stable pattern. I show that the AG expression occurs in two phases: a low-expression phase and a high-expression phase. Thus although all cells of the central dome of the flower present similar profiles of AG activation, the precise developmental time at which AG is activated is different in each case, and is the origin of the initial stochastic pattern. With the aid of the model, I also propose four new hypotheses to explain AG regulation: AG is able to maintain its own activation by directly binding its own second intron through a protein complex containing at least two molecules of AG leading to the creation of an auto-activation threshold.AP2 influences the value of this threshold, restraining AG expression to the central dome of the flower and producing a delay in complete AG activation.LFY and WUS are necessary to accumulate AG proteins in cells in order to reach the auto-activation threshold and obtain a full expression of AG.AG movement is necessary to obtain expression of AG in every cell of the central dome. To prove these hypotheses, I have carried out various experiments, using FRET-FLIM in protoplast cells, we suggest that AG is able to form homo-dimers in plant cells. However, overexpressing AG to help cells reach the auto-activation threshold earlier than in the wild-type does not appear to alter the endogenous AG dynamics of expression. Secondly, I test the precise role of LFY in the different phases and transitions in the AG expression dynamics by mutating specific interaction sites for LFY within AG regulatory sequences. These mutations appear to delay AG expression and slightly modify its pattern of expression. I show that only important delays in AG activation induce phenotypic differences. Then, to test the role of AP2 repression in AG expression dynamics, I analyse the AG reporter in the context of a strong ap2 mutant. In these mutants, AG expression spreads to a wider region and reduces the delay between the onset of AG expression and the transition from low- to high-expression. These results match with simulations of the model. Lastly, to understand the importance of AG cell-to-cell movement in AG dynamics, I block its ability to move using a nuclear localisation tag. Although this induces a delay in the activation of few cells at stage 3, when all cells of the central dome of the flower express AG in the WT. This delay has no visible effects on the phenotype
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Ventura, Maria Teresa Mateus. "Cortisol e testosterona no plasma da grávida e no líquido amniótico: variação com o relaxamento e correlação com o rácio digital 2D:4D no recém-nascido." Doctoral thesis, Faculdade de Ciências Médicas. UNL, 2013. http://hdl.handle.net/10362/10306.
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RESUMO: Conclusão - Este estudo sugere que mulheres grávidas beneficiam da prática rotineira de 30 min de relaxamento perante a eminência de um acontecimento indutor de stress. O benefício será tanto psicológico como fisiológico e será mais marcado de manhã do que de tarde. As mulheres com maior
tendência ansiosa, tipicamente as mais jovens e com menos idade gestacional, serão as que mais beneficiam. Entre os tipos de intervenção experimentados, todos eles não dispendiosos, a audição de música foi globalmente o mais eficaz para o propósito pretendido. A variação do cortisol e a variação da testosterona estão altamente correlacionadas, e este efeito poderá
ser explorado em futuras intervenções relaxantes. Programas curtos de relaxamento poderão conduzir a benefícios para o bem-estar psicológico e para a saúde da grávida, com benefícios adicionais no desfecho da gravidez.
O rácio digital 2D:4D do recém-nascido apresenta características sexualmente dimórficas, sendo mais baixo em rapazes que em raparigas, confirmando a influência dos androgénios pré-natais, mas há grande
sobreposição entre os sexos pelo que, isoladamente, não pode ser utilizado como marcador de risco. No entanto, se associado a outros marcadores biológicos, como o peso ao nascer e a circunferência cerebral,
entre outros, poderá ser um parâmetro a valorizar desde cedo, possivelmente no acompanhamento pediátrico.
Nas raparigas, o RD da mãe e a testosterona no LA explicam uma proporção significativa do seu 2D:4D. Em ambos os sexos, o rácio 2D:4D aumenta após o nascimento e o dimorfismo sexual observado com base em
amostras de crianças com mais de dois anos de idade, é afectado pela testosterona pós-natal, especialmente no que se refere à mão direita.----------ABSTRACT: Conclusions - This study suggests that pregnant women would benefit from the routine practice of 30min relaxation when at the imminence of a stressful event. The benefit would be both psychological and physiological and would be more pronounced in the morning than in the afternoon. Women tending to be more anxious, typically younger and at a lower gestational age, are the ones that benefit the most. Among the interventions investigated, all being non-expensive and easy to implement, listening to relaxing music was globally the most efficient for the benefit intended.
The variation of cortisol and the variation of testosterone are significantly correlated, an association that might be used in future relaxation interventions. It is feasible to conceive short relaxation programs aimed at benefiting psychological well-being and health in pregnancy, with additional benefits for pregnancy outcome.
The digital ratio 2D:4D is sexually dimorphic, being lower in males than in females, confirming the influence of pre-natal androgens. There is however large overlap between sexes, rendering the 2D:4D a risk marker not to be used in isolation but rather in association with other markers, like for instance the weight at birth and the head circumference, wherein it may be a relevant parameter for pediatric follow-up.
In newborn females, a significant amount of variability in 2D:4D is accounted for by their mother’s digital ratio and AF testosterone. In both sexes, the 2D:4D ratio increases following birth and sexual dimorphism,as assessed from samples of subjects with more than 2 years of age, is affected by post-natal testosterone,
especially in what concerns the right hand.
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Abichou, Mariem. "Modélisation de l’architecture 4D du blé : identification des patterns dans la morphologie, la sénescence et le positionnement spatial des organes dans une large gamme de situations de croissance." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLA022/document.
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La simulation de l’architecture des plantes est devenue un front de recherche très actif, en raison de son importance pour la compréhension du fonctionnement des plantes et de leurs interactions avec l’environnement. Simuler l’architecture d’une plante au cours du temps implique de représenter la morphologie, la dynamique de mise en place et de senescence, et le positionnement spatial des différentes composantes de la plante. Ces caractéristiques sont dépendantes de l’environnement et varient d’un cultivar à un autre. Une difficulté principale des modèles architecturaux est d’assurer une flexibilité suffisante pour s’adapter à la plasticité liée aux conditions de croissances. Pouvoir simuler l’architecture d’un peuplement avec une fidélité suffisante pour simuler les traits spécifiques issus d’une expérimentation présente un grand intérêt dans l’analyse de cette expérimentation. Par exemple, ces reconstructions permettront d’accéder à des variables d’intérêt peu on non accessibles à la mesure directes et d’évaluer des hypothèses sur le fonctionnement des plantes. Couplées à des modèles physiques, ces reconstructions permettront aussi de mieux comprendre l’impact de l’architecture sur l’interception du rayonnement et de particules telles que des spores ou des gouttelettes de pesticides, ou sur la formation de signaux perçus par les capteurs en phénotypage. Ces applications sont au cœur des thématiques de l’UMR ECOSYS et intéressent Arvalis-institut de végétal qui finançait ce projet de thèse. Dans ce contexte, l’objectif de mon travail de recherche a été de développer un modèle opérationnel qui permette de reproduire par simulation l’architecture 4D d’un peuplement pour tout le cycle de culture et de façon fidèle aux observations. Notre démarche s’appuie sur la caractérisation expérimentale d’une gamme de cultivars commerciaux cultivés dans la région parisienne. Ces données représentent une gamme large de séquences climatiques, dates et densités de semis, espacements entre rangs et fertilisation azotée. L’analyse de ces données nous a permis d’identifier des patterns stables et robustes décrivant les dynamiques d’apparition et de mortalité des différentes composantes de la plante, leurs dimensions finales et leur géométrie au cours du temps. Ces patterns sont exprimés en fonction de stade de développement de la plante (Haun stage), de nombre final de feuilles ou de la position de l’organe sur l’axe. Une attention particulière a été portée à l’estimation des caractéristiques des talles à partir de celles du brin maitre. Ces fonctions ont été regroupées dans une routine permettant de décrire la dynamique complète de l’architecture d’une collection de plantes de l’émergence jusqu’à la maturité. Un protocole de mesure a été aussi défini pour estimer les paramètres avec un effort expérimental raisonnable où l’ensemble des mesures sont à réaliser sur le brin maitre.Notre méthode de reconstruction a permis de générer les reconstructions 4D d’une part importante de nos données expérimentales; elle a également été mise en œuvre dans plusieurs projets menés parallèlement à mon travail. Notre modèle peut être aussi utilisé pour explorer des architectures potentielles en vue de proposer des nouveaux ideotypes. Finalement, notre démarche de modélisation est transposable à d’autres céréales : elle fournit un cadre pour comparer les patterns de morphologie et de développement entre espèces et un outil pour étudier par simulation l’impact des traits architecturaux caractéristiques de chaque espèce<br>The simulation of plant architecture has become a very active front of research because of its importance for understanding the functioning of plants and their interactions with the environment. When analysing observations of experimental treatments, it is of a great interest to be able to simulate the architecture of the crop with sufficient fidelity to represent the specific traits resulting from the experiment. In this context, the objective of the thesis project was to develop an operational model allowing to simulate the 4D architecture of a collection of individual plants for the whole crop cycle and in a way faithful to the observations. Our approach builds on the experimental characterization of a range of commercial cultivars cultivated in the Paris region. These data represent a wide range of climatic sequences, sowing dates, densities of seedlings and nitrogen fertilization. The data analysis allowed us to identify stable and robust functions that describe the dynamics of appearance and mortality and the final dimensions of the different components of the plant. Our work brings also novel information on the evolution of their geometry and spatial organisation over time. These functions were coded into a model that describes the dynamics of the architecture of a collection of plants from their emergence to their full maturity. Our reconstruction method allowed us to generate 4D reconstructions for a large part of our experimental treatments; it has also been used in several projects carried out in parallel with this work. Our model can also be used to explore potential architectures traits in order to propose new ideotypes. Finally, our modelling approach can be applied to other cereals: it provides a framework for comparing patterns of morphology and development between species and provides a tool to study, by simulation, the impact of the architectural traits of each species
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Birkhold, Annette Isabell [Verfasser], Georg N. [Akademischer Betreuer] Duda, Peter [Akademischer Betreuer] Fratzl, Marc [Gutachter] Kraft, Georg N. [Gutachter] Duda, and Peter [Gutachter] Fratzl. "A 4D imaging approach to monitor bone remodeling : development, design, validation and first applications of a tomography-based medical image processing method and tool for enhanced visualization and quantification of patho-physiological dynamic structural processes in bone / Annette Isabell Birkhold ; Gutachter: Marc Kraft, Georg N. Duda, Peter Fratzl ; Georg N. Duda, Peter Fratzl." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156180007/34.
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Franzén, Ähdel Carina, and Wilén Frida Bulukin. "Alla vill varandras väl : Hur ledarskap genom medarbetarskap i en kvalitetskultur skaparpatientnöjdhet vid svenska sjukhus." Thesis, Mittuniversitetet, Avdelningen för kvalitets- och maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-38812.
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Engagerat ledarskap är grunden till att skapa en god kvalitetskultur och för attlyckas krävs medarbetarskapets delaktighet. Forskare menar att stödet förnärvarande ledare i vården har fram tills idag varit tämligen outvecklat. Syftetmed denna studie var att förstå framgångsfaktorer för hur kvalitetskulturen isvensk sjukvård kan kopplas mot ledarnas möjlighet att främja ett gottmedarbetarskap. Detta utifrån en förklarande sekventiell mixad metod med tvåkvantitativa mätningar som slutligen resulterade i en kvalitativ intervju. Enmätning av kvalitetskulturen vid svenska sjukhus utfördes utifrån ett tidigareframtaget mätinstrument för att mäta kvalitetskultur. Mätinstrumentetpresenterades genom 13 beteendepar som främjar respektive hindrar enkvalitetskultur. Denna mätning visade att det idag råder en generellt godkvalitetskultur vid svenska sjukhus. Genom denna mätning kunde enregressionsanalys utföras som kopplades samman mot sjukhusens resultat iNationell patientenkät. Ett statistiskt signifikant beteende kunde uppmätassom enligt denna mätning skapar nöjdare patienter ju mer medarbetarnaupplever att detta beteende förekommer i deras organisation. Beteendet ärnär vi har ett problem tar vi reda på grundorsaken innan vi beslutar om enlösning. Detta beteende togs med till två framgångsrika sjukhus för att djupareförstå hur dessa arbetar med medarbetarskapet i just detta beteende. Utifrånworkshop med dessa två sjukhus är slutsatsen att ledare behöver ha erfaritden kvalitetskultur och det medarbetarskap de ska bära för att främja ettmedarbetarskap som kopplats samman med kvalitetskulturen. I jakten på attnå framgång är en stark kvalitetskultur eftersträvansvärd men utifrånworkshoparna ser författarna ingen möjlig snabb lösning för att nå dit.Resultatet visar att dagens ledare i vården behöver stöd i form av mentor ellerreflektion kring ledarskap själv eller i grupp för att utvecklas. I konstruktiv andaär det med förbättringskunskap i grunden som allas delaktighet i arbetet medständiga förbättringar bedrivs. Detta kräver allas reflektion, ärlighet, mod,öppenhet och förtroende där allt grundar sig i att alla vill varandras väl!<br>Committed leadership is the foundation for creating a good quality culture andto succeed, the participation of employees is required. Researchers argue thatsupport for the current leaders in healthcare has until now been ratherundeveloped. The purpose of this study was to understand how the qualityculture in Swedish healthcare can be linked to the leaders' ability to promotegood co-workership. This study was based on an explanatory sequentialmixed method with two quantitative measurements that ultimately resulted in aqualitative interview. A measurement of the quality culture at Swedishhospitals was taken based on a previously developed instrument formeasuring quality culture . The measuring instrument comprises 13behavioral pairs that promote or hinder a quality culture. This measure showsthat there is generally a good quality culture at Swedish hospitals at present.Through this measurement, a regression analysis was done which links to thehospital's results in the National Patient Survey. A statistically significantbehavior was observed, and according to this measurement, is likely to createmore satisfied patients as more professions feel that this behavior occurs intheir organization. The behaviour in question can be described as: when wehave a problem, we find out the root cause before we decide on a solution.This behavior was brought into two successful hospitals in order to understandmore deeply how they work with the co-workership in this particular behavior.Based on the workshop with these two hospitals, we conclude that leadersneed to have experienced the quality culture and the co-workership they areassumed to carry in order to promote an employee culture that is linked to thequality culture. In pursuit of success, a strong quality culture is desirable, butbased on the workshops, the authors see no possible quick solution to reachit. The result shows that today's leaders in healthcare need support in the formof a mentor or time for reflection on leadership on their own or in groups inorder to develop. In constructive approach, it is with improvement knowledgethat everyone's involvement in the work of continuous improvement isconducted. This requires reflection, honesty, courage, openness and trustfrom everyone involved and intentions rooted in the wellness and prosperity ofall.<br><p>2019-06-27</p>
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WU, SHENG-YU, and 吳盛祐. "Development of 4D Mission Programming for UAV Swarm." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/r2382p.
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碩士<br>國立虎尾科技大學<br>自動化工程系碩士班<br>107<br>To improve the path planning algorithm for UAV swarm by adding the mathematical model of time dimension to achieve a 4D mission assignment that including a path programming to arrive target locations at a specified time, is the object of this research.
To solve this 4D dynamic path programming problem for UAV swarm mission, we use the 2-phase Tabu search with 2-Opt exchange method and A* search as the 3D path programming algorithm. First, let distance as a cost function for path programming, on the premise that load balance distance, and minimum total distance for the optimization of algorithm. Second, acquire an equation from MATLAB which is according to the flight database collected in this research, fitting the 5 parameters that affect the mission time to get the sextic equation. Finally, substitute the path planning result and set time into the equation, find the approximate velocity of the variable by Newton's method, in order to change the flight velocity of the path to control the completion time, and feasibility analysis of this mission. Expect quadcopter UAV swarm can not only load balanced but also reach the most efficient to complete the specified mission at the specified time, through the ground control system developed by this research, sequencing or simultaneous arrival of UAV swarm mission can be achieve.
The final experiments successfully showed each UAV in the swarm can arrive assigned target points at specific times. The average error in this mission time control experiment was less than 3.6%.
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Chen, Hsin-Yu, and 陳信佑. "Guideline Development of BIM/4D Applications for Owners." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/kvsc88.
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碩士<br>國立中央大學<br>營建管理研究所<br>107<br>In recent years, Building Information Modeling (BIM) technique has received much attention from the government. Public construction works implement this technique increased gradually. Among all BIM applications, 4D simulation has been used in many construction projects in Taiwan. BIM/4D simulation is produced by BIM 3D model with project timelines. Through the visualization of 4D simulation, BIM/4D helps the user to review construction processes or sequences and then to understand design and construction outcomes. One of the major problem of BIM/4D implementation is unclear implementation objectives and deliverables in a contract. This usually results in contract disputes. Based on several contracts with BIM/4D implementation in Taiwan, this study analyzes owner’s requirements and implementation obstacles, and further identifies eight BIM/4D uses. This study also constructs a 3D model based on a real construction case and tests the feasibility of identified eight BIM/4D uses. The outcomes of this study is a BIM/4D applications guideline for owners that has been validated by domain experts. It is anticipated that the research outcomes can improve the effectiveness and benefits of BIM/4D in Taiwan.
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Chen, Guan-Yu, and 陳冠宇. "Development of Model-based 3D and 4D Cardiac Ultrasound System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/01757653067759926731.
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碩士<br>國立清華大學<br>電機工程學系<br>93<br>Though the medical image techniques of the present day, such as CT and MRI, produce images with good quality, the great expense for necessary equipment and the long time required for obtaining image data make these techniques unhandy. Contrary to these techniques, ultrasound imaging is superior for fast imaging and low cost. And it has been one of the most important and universal diagnostic tools nowadays.2D ultrasound provides physicians with entire 2D information and makes the diagnosis more easily. But in some situations, physicians still need to spend their imagination on building up a 3D image from separated 2D images for making correct diagnosis. So, 3D ultrasound related researches have received significant attention. Although the commercial 3D ultrasound system has been carried out, it can’t provide cardiac scanning due to the mechanical design of its transducer. So we put our attention on how to build up a 3D image from 2D ultrasound images. To build up a 3D volume, we need to know all the positions of 2D slices. And how to get the positions becomes an important problem. We create a standard heart model which can be modulated. Before making 2D ultrasound scanning, we can adapt the standard model to approach the patient’s heart model. Once having the patient’s heart model, we can compute the positions where the 2D slices are in the heart model.
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Goyat, Jean. "Using 3D/4D CAD modeling for traffic management : development, review, and communication." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-05-5005.
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Developing a traffic management plan for a transportation infrastructure project is a complex activity which requires input from many different fields. Ideally, design, construction and traffic engineers all work towards devising an integrated traffic management plan that would consider a variety of aspects. Current literature about traffic management modeling mostly focuses either on high-level tools not adequate to perform required phasing and constructability analysis of construction activities, or study pre- and post-construction conditions. On the other hand, computer aided design (CAD) modeling of infrastructure projects mentions potential benefits for traffic management plan reviewing. However, it does not delve into using 3 dimensional (3D) and 4 dimensional (3D and time) CAD to study (1) the impact of construction activities on traffic, (2) during construction, (3) at a level that allows detailed phasing and constructability reviews for traffic management plan elaboration and communication. Using 3D and 4D CAD modeling can alleviate the complexity of devising traffic management plans for transportation projects by providing an integrated framework from which developers can elaborate, review and communicate their strategies. The many visualization benefits of 3D/4D modeling used in conjunction with their advanced analysis capabilities can tremendously aid compared to more traditional 2D methods. The three transportation projects described in this study aim at illustrating the benefits and added value these models provide to more efficiently and rapidly visualize and analyze intended traffic management strategies, at different stages of the construction process.<br>text
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Wang, Hsuan Ting, and 王軒庭. "Development of a 4D dosimetric evaluation system for liver cancers in proton therapy." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/tkye5d.
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碩士<br>長庚大學<br>醫學影像暨放射科學系<br>104<br>Proton therapy is sensitive to treatment uncertainty. During the process of proton treatment, respiratory motion causes significant dose uncertainty for liver cancer patients. One patient was included in the study for developing a 4-dimensional (4D) dosimetry evaluation system for proton liver treatments and studying dose variation due to respiratory motion.
4D dose distribution was obtained from applying the same treatment plan to 10 phase images of the 4D computer tomography, representing a complete respiratory cycle of the patient. To sum up doses from the 10 dose plans, two open source codes based on MATLAB were implemented in the study for 4D dose deformation and processing: Computational Environment for Radiotherapy Research (CERR), and Deformable Image Registration Adaptive Radiotherapy (DIRART).
At last, DVHs (Dose-Volume histogram), isodose curves, dose profiles were used to compare traditional 3D dose and 4D dose plans. In the study, we successfully developed a dosimetry system to evaluate more realistic dose distribution under the presence of respiratory motion for liver cancer treatments in proton therapy.
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Liu, Yilin. "Development and Optimization of Four-dimensional Magnetic Resonance Imaging (4D-MRI) for Radiation Therapy." Diss., 2016. http://hdl.handle.net/10161/12267.
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<p>A tenet of modern radiotherapy (RT) is to identify the treatment target accurately, following which the high-dose treatment volume may be expanded into the surrounding tissues in order to create the clinical and planning target volumes. Respiratory motion can induce errors in target volume delineation and dose delivery in radiation therapy for thoracic and abdominal cancers. Historically, radiotherapy treatment planning in the thoracic and abdominal regions has used 2D or 3D images acquired under uncoached free-breathing conditions, irrespective of whether the target tumor is moving or not. Once the gross target volume has been delineated, standard margins are commonly added in order to account for motion. However, the generic margins do not usually take the target motion trajectory into consideration. That may lead to under- or over-estimate motion with subsequent risk of missing the target during treatment or irradiating excessive normal tissue. That introduces systematic errors into treatment planning and delivery. In clinical practice, four-dimensional (4D) imaging has been popular in For RT motion management. It provides temporal information about tumor and organ at risk motion, and it permits patient-specific treatment planning. The most common contemporary imaging technique for identifying tumor motion is 4D computed tomography (4D-CT). However, CT has poor soft tissue contrast and it induce ionizing radiation hazard. In the last decade, 4D magnetic resonance imaging (4D-MRI) has become an emerging tool to image respiratory motion, especially in the abdomen, because of the superior soft-tissue contrast. Recently, several 4D-MRI techniques have been proposed, including prospective and retrospective approaches. Nevertheless, 4D-MRI techniques are faced with several challenges: 1) suboptimal and inconsistent tumor contrast with large inter-patient variation; 2) relatively low temporal-spatial resolution; 3) it lacks a reliable respiratory surrogate. In this research work, novel 4D-MRI techniques applying MRI weightings that was not used in existing 4D-MRI techniques, including T2/T1-weighted, T2-weighted and Diffusion-weighted MRI were investigated. A result-driven phase retrospective sorting method was proposed, and it was applied to image space as well as k-space of MR imaging. Novel image-based respiratory surrogates were developed, improved and evaluated.</p><br>Dissertation