Дисертації з теми "Inversion modelling"
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Yamada, Yasuhiro. "3D analogue modelling of inversion structures." Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311874.
Повний текст джерелаArdjmandpour, Negah. "Modelling and Inversion of Array Induction tool." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522875.
Повний текст джерелаMillington, Timothy M. "Modelling and inversion of ground penetrating radar." Thesis, Keele University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540623.
Повний текст джерелаZhang, Ai Jun. "Modelling and inversion of two-dimensional magnetotelluric data." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/14717.
Повний текст джерелаLewi, Elias. "Modelling and inversion of high precision gravity data /." München : Bayerische Akademie der Wissenschaften, 1997. http://catalogue.bnf.fr/ark:/12148/cb409231411.
Повний текст джерелаRücker, Carsten. "Advanced Electrical Resistivity Modelling and Inversion using Unstructured Discretization." Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-69066.
Повний текст джерелаTsourlos, Panagiotis. "Modelling, interpretation and inversion of multielectrode resistivity survey data." Thesis, University of York, 1995. http://etheses.whiterose.ac.uk/14017/.
Повний текст джерелаStek, Ivan. "Frequency domain seismic forward modelling : a tool for waveform inversion." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267748.
Повний текст джерелаVieira, da Silva Nuno Miguel. "Three-dimensional modelling and inversion of controlled source electromagnetic data." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9120.
Повний текст джерелаYeo, Leslie Yu-Ming. "Modelling of phase inversion and associated phenomena in liquid-liquid systems." Thesis, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480683.
Повний текст джерелаFurst, Séverine. "Multi-objective optimization for joint inversion of geodetic data." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS017/document.
Повний текст джерелаThe Earth’s surface is affected by numerous local processes like volcanic events, landslides or earthquakes. Along with these natural processes, anthropogenic activities including extraction and storage of deep resources (e.g. minerals, hydrocarbons) shape the Earth at different space and time scales. These mechanisms produce ground deformation that can be detected by various geodetic instruments like GNSS, InSAR, tiltmeters, for example. The purpose of the thesis is to develop a numerical tool to provide the joint inversion of multiple geodetic data associated to plate deformation or volume strain change at depth. Four kinds of applications are targeted: interseismic plate deformation, volcano deformation, deep mining, and oil & gas extraction. Different inverse model complexities were considered: the I-level considers a single type of geodetic data with a time independent process. An application is made with inverting GPS data across southern California to determine the lateral variations of lithospheric rigidity (Furst et al., 2017). The II-level also accounts for a single type of geodetic data but with a time-dependent process. The joint determination of strain change history and the drift parameters of a tiltmeter network is studied through a synthetic example (Furst et al., submitted). The III-level considers different types of geodetic data and a timedependent process. A fictitious network made by GNSS, InSAR, tiltmeters and levelling surveys is defined to compute the time dependent volume change of a deep source of strain. We develop a methodology to implement these different levels of complexity in a single software. Because the inverse problem is possibly ill-posed, the functional to minimize may display several minima. Therefore, a global optimization algorithm is used (Mohammadi and Saïac, 2003). The forward part of the problem is treated by using a collection of numerical and analytical elastic models allowing to model the deformation processes at depth. Thanks to these numerical developments, new advances for inverse geodetic problems should be possible like the joint inversion of various types of geodetic data acquired for volcano monitoring. In this perspective, the possibility to determine by inverse problem the tiltmeter drift parameters should allow for a precise determination of deep strain sources. Also, the developed methodology can be used for an accurate monitoring of oil & gas reservoir deformation
Pearse, Scott. "Inversion and modelling of seismic data to assess the evolution of the Rockall Trough." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289610.
Повний текст джерелаClewley, Daniel. "Retrieval of forest structure and biomass from radar data using backscatter modelling and inversion." Thesis, Aberystwyth University, 2011. http://hdl.handle.net/2160/6d359d2b-806a-4ce8-a69a-c44ce30db088.
Повний текст джерелаAbtahi, Sayyed Mohammad. "Airborne Gravity Gradient, Magnetic and VLF datasets : Case studies of modelling, inversion and interpretation." Doctoral thesis, Uppsala universitet, Geofysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300126.
Повний текст джерелаSafani, Jamhir. "Surface wave dispersion modelling by full-wavefield reflectivity and inversion for shallow subsurface imaging." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136173.
Повний текст джерелаNzikou, Mamboukou Michel. "Forward Modelling and Inversion of the Ultrasonic Wave Propagation Through a Homogeneous and Porous Rock." Thesis, Curtin University, 2019. http://hdl.handle.net/20.500.11937/76000.
Повний текст джерелаPanien, Marion. "Analogue modelling experiments of basin inversion using well-characterised granular materials and comparisons with numerical models /." [S.l.] : [s.n.], 2004. http://www.zb.unibe.ch/download/eldiss/04panien_m.pdf.
Повний текст джерелаGrinc, Michal. "Lithospheric structure in Central Europe : integrated geophysical modelling." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00921044.
Повний текст джерелаWiik, Torgeir. "Modelling of Electromagnetic Fields in Conductive Media and development of a Full Vectorial Contrast Source Inversion Method." Thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9684.
Повний текст джерелаSeismic surveys are well established in hydrocarbon prospecting, and technology for processing seismic data has been developed through decades. The first electromagnetic survey for hydrocarbon prospecting however, was performed in 2000, and as a consequence of the short time span the technology is not as well developed as in seismics. For instance, the need for efficient and robust forward modelling software and inversion schemes for collected data is urgent. In this thesis forward modelling using integral equations and the Contrast Source Inversion (CSI) method is investigated for forward and inverse 3D electromagnetic scattering experiments in hydrocarbon prospecting, respectively. The mathematical model is developed in an arbitrary isotropic, conductive medium, with contrast in electric permittivity and electric conductivity between the scattering object and the background, while in the numerical examples the background model is restricted to a horizontally layered medium with variations in the $z$-direction only and contrast in electric conductivity. The difference in electric conductivity is considered the backbone of electromagnetic hydrocarbon prospecting. The main result concerning forward modelling in this thesis is the establishment of a, to my knowledge, previously unpublished method for solving the electric Lippmann-Schwinger equation in a conductive medium by fixed point iteration. In the inversion part of this thesis the previously scalar CSI method is extended to a full vector valued method. A new CSI method for inversion with respect to all the electromagnetic parameters (the electric permittivity, electric conductivity and magnetic permeability) is also presented, which I have yet to find treated elsewhere. Only the former method is tested numerically, using synthetic data, due to the computational complexity of the latter. The numerical results from the forward modelling show the numerical validity of integral equation modelling and the fixed point iteration, whereas the results from the inversion show some promise. With several source and receiver lines present the lateral position of the scattering object is reconstructed well, whereas the vertical position causes problems. When textit{a priori} information about the position of the scattering object is introduced to further regularise the problem, the approximate position of it is successfully inverted, which illustrates the essential part additional regularisation plays in this inverse scattering problem. Thus the CSI method could be useful in petroleum geophysics, and should be developed further for the purpose of locating hydrocarbons in the subsurface. Several possibilities for further work is noted. This work was performed for StatoilHydro ASA.
Rücker, Carsten [Verfasser], Franz [Akademischer Betreuer] Jacobs, and Ugur [Akademischer Betreuer] Yaramanci. "Advanced Electrical Resistivity Modelling and Inversion using Unstructured Discretization / Carsten Rücker. Gutachter: Ugur Yaramanci. Betreuer: Franz Jacobs." Leipzig : Universitätsbibliothek Leipzig, 2011. http://d-nb.info/1020089210/34.
Повний текст джерелаSheffer, Megan Rae. "Forward modelling and inversion of streaming potential for the interpretation of hydraulic conditions from self-potential data." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/235.
Повний текст джерелаSundsby, Ole. "Forward modelling and seismic inversion for unmasking of gas reservoirs in the Patchawarra Formation, Cooper Basin, South Australia /." Title page, abstract and contents only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbs958.pdf.
Повний текст джерелаPassalacqua, Olivier. "Localiser une archive glaciaire de 1.5 millions d'années par une approche multi-modèles." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU024/document.
Повний текст джерелаAntarctic ice is an exceptional archive of ancient atmospheric air. The oldest available ice archive (800 ka) is not old enough to study a main climatic transition that occurred between 1.2 Ma and 0.9 Ma (mid-Pleistocene transition). Locating a future old-ice drill site is now one of the main goal of the ice-core community. In the region of Dome C, several old-ice targets have required characteristics, from a thermal and mechanical point of view, to hosts very old ice. The goal of this work is to precisely locate suitable coring sites, using several glaciological models. First a 1D heat model to compute the local geothermal flux, that make us confident in the fact that bedrock heights have been free of basal melting for at least the last 800 ka. It is very likely that such sites are able to host a 1.5 Ma ice archive. Second, a 3D ice flow model, to describe the ice trajectories from the ice surface to the bed. Drilling less than 10 km from the surface ridge mimimizes the risks of stratigraphic disturbance, and drilling on the flanks of the bed relief - and not on its top - is mandatory to ensure a sufficient age resolution. Third, a 1D dating model constrained by isochrones let us describe the distribution of basal ages and age resolutions compatible with observed isochrones, and assess the risk of success or failure of the drilling. With currently available data and modelling tools, two drilling sites are proposed that are located 37 km from Dome C, at which 1.5 Ma-old ice is very likely to be archived in required conditions and with sufficient resolution
Prézélus, Flavie. "Ecodesign of ultrafiltration membranes for drinking water production : an experimental and modelling approach." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0088.
Повний текст джерелаAlthough ultrafiltration treatment processes are widely used for drinking water applications, their environmental performances remain poorly understood. The objectives of this work are to provide understanding of membrane environmental footprint, as well as to suggest and implement relevant innovative solutions for its mitigation. A multiphase ecodesign approach is applied to hollow fibres fabricated by phase inversion and operated in a dead-end mode. The two developed parameterized models evaluate environmental impacts during fabrication and operation as a function of operating conditions. The subsequent Life Cycle Assessment highlights glycerol-related operating conditions as interesting action levers for environmental mitigation of membrane fabrication. However, membrane operation accounts for nearly exclusively all environmental impacts, with electricity production and sodium hypochlorite fabrication as the two main contributors. The analysis also pinpoints the influence of filtration flux. Since opportunities for biosourced solvents exist, substitution of petrochemical solvents during membrane fabrication is chosen as an improvement strategy. A metrics-based methodological framework is suggested to rationalize sustainable membrane fabrication. Biosourced flat membranes using methyl lactate as a solvent have thus been prepared. The mixed environmental scores do not preclude solvent substitution as a relevant improvement strategy. Results highlight the feasibility and relevance of such an ecodesign approach based on process modelling and experimental work, and lay the foundations for further development
Kanj, Mahmoud. "Inversion de données électromagnétiques par algorithme génétique pour la télédétection en zone forestière." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112350/document.
Повний текст джерелаThe objective of radar imaging is to characterize the observed target. In the case of forest remote sensing, the objective is to extract the component of the vegetation physical parameters.This manuscript addresses the problem of the inversion of electromagnetic data for low frequency wave, VHF band to the P band. In these frequency bands, the canopy (leaves and small branches) does not almost interact with the radar wave and the forest can thus, in first approximation, be represented by vertical cylinders (trunks) and tilted (primary branches).In this context, the numerical electromagnetic methods of inversion lean on models which calculate, many times, the scattered fields radiated by such broadcasters. It is then necessary to choose a physical model which compromise speed/accuracy tilts in favor of the speed, thus a "approached" model. The exactness of the chosen model is then studied and then validated by comparison to a model which the compromise speed/accuracy is inverted, thus a "exact" model. Among the many numerical methods of inversion, that of the genetic algorithm (AG) was chosen. This algorithm, well known, is analyzed here then improved to meet the requirements of the composed electromagnetic problem. It is then validated on simulated and measured data. This validation is also an opportunity to study the impact of the set of data used on the speed and the precision of the inversion, according to the configurations of antenna (frequencies, positions, polarizations)
Wittke, Jan [Verfasser], Bülent [Gutachter] Tezkan, Klaus [Gutachter] Spitzer, and Becken [Gutachter] Michael. "Meshless methods for Maxwell’s equations with applications to magnetotelluric modelling and inversion / Jan Wittke ; Gutachter: Bülent Tezkan, Klaus Spitzer, Becken Michael." Köln : Universitäts- und Stadtbibliothek Köln, 2017. http://d-nb.info/1148623698/34.
Повний текст джерелаMichon, Timothée. "Extension du potentiel de la modélisation hydrologique. : inversions heuristiques de modèles pluie-débit pour l'identification des paramètres simultanément aux pluies ou à la courbe de tarage." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAA005/document.
Повний текст джерелаRainfall-runoff models are used for flood forecasting by warning authorities. However their implementation on a particular territory is still a challenge. Indeed, they generally need to be calibrated by using observed rainfall and discharge time series. These data may be subject to errors and uncertainties. They are not always available. Then, the model calibration relevancy may be affected and the forecasts may also be subject to significant uncertainties. This research would like to address such issues related to the rainfall-runoff models calibration, by proposing original methods which may set up a model by using less data than the ``classical'' calibration. The unused data might be either subject to uncertainties or not available. Moreover, these unused data may be estimated by the methods. Two model independant approach were suggested. Both are an heuristic inversion algorithm of rainfall-runoff models. The first method estimates simultaneously hourly rainfall time series and models parameters, by using only observed hourly discharge time series and total areal rainfall of flood events. A specific application of this method to set up models (with fixed parameters), generalises to models which are not invertible analyticaly, the ``hydrology backward'' approach proposed by Kirchner (2009).The second method estimates simultaneously models parameters and a rating-curve, by using only observed hourly rainfall and stage time series. Original analysis may be performed on the rainfall time series and the rating-curve estimated by the methods. Also, they extend the applicability rainfall-runoff models to hydrological context with restricted available data and offer promising operational applications. Yet, this research lead us to build a conceptual framework, denoted knowledge space. This framework unifies not only the original approaches which were proposed, but also some more ``classical'' approaches to hydrology as the calibration and the simulation
Boumaaza, Bouharket. "3D seismic attributes analysis and inversions for prospect evaluation and characterization of Cherokee sandstone reservoir in the Wierman field, Ness County, Kansas." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35510.
Повний текст джерелаDepartment of Geology
Abdelmoneam Raef
Matthew W. Totten
This work focuses on the use of advanced seismically driven technologies to estimate the distribution of key reservoir properties which mainly includes porosity and hydrocarbon reservoir pay. These reservoir properties were estimated by using a multitude of seismic attributes derived from post-stack high resolution inversions, spectral imaging and volumetric curvature. A pay model of the reservoir in the Wierman field in Ness County, Kansas is proposed. The proposed geological model is validated based on comparison with findings of one blind well. The model will be useful in determining future drilling prospects, which should improve the drilling success over previous efforts, which resulted in only few of the 14 wells in the area being productive. The rock properties that were modeled were porosity and Gamma ray. Water saturation and permeability were considered, but the data needed were not available. Sequential geological modeling approach uses multiple seismic attributes as a building block to estimate in a sequential manner dependent petrophysical properties such as gamma ray, and porosity. The sequential modelling first determines the reservoir property that has the ability to be the primary property controlling most of the other subsequent reservoir properties. In this study, the gamma ray was chosen as the primary reservoir property. Hence, the first geologic model built using neural networks was a volume of gamma ray constrained by all the available seismic attributes. The geological modeling included post-stack seismic data and the five wells with available well logs. The post-stack seismic data was enhanced by spectral whitening to gain as much resolution as possible. Volumetric curvature was then calculated to determine where major faults were located. Several inversions for acoustic impedance were then applied to the post-stack seismic data to gain as much information as possible about the acoustic impedance. Spectral attributes were also extracted from the post-stack seismic data. After the most appropriate gamma ray and porosity models were chosen, pay zone maps were constructed, which were based on the overlap of a certain range of gamma ray values with a certain range of porosity values. These pay zone maps coupled with the porosity and gamma ray models explain the performance of previously drilled wells.
Li, Siqian. "The atomic struture of inversion domains and grain boundaries in wurtzite semonconductors : an investigation by atomistic modelling and high resolution transmission electron microscopy." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC252/document.
Повний текст джерелаIn this work, we investigated two kinds of interfacial defects: inversion domain boundaries (IDBs) and grain boundaries (GB) in wurtzite semiconductors (III-nitrides, ZnO and ZnO/GaN heterostructure) using high-resolution TEM and first-principle calculations. For IDBs, theoretical calculation indicated that a head-to-head IDB with an interfacial stacking sequence of AaBbAa-AcCaA (H4) is the most stable structure in wurtzite compounds. Moreover, 2-dimensional electron gas (2DEG) and 2-dimensional hole gas (2DHG) build up in head-to-head and tail-to-tail IDBs, respectively. Considering the IDB at the ZnO/GaN heterointerface, TEM observations unveiled the H4 configuration with a -Zn-O-Ga-N interface. Moreover the theoretical investigation also confirmed stability of this interface along with the corresponding formation of a 2DHG. A detailed topological, TEM and theoretical investigation of [0001] tilt Grain Boundaries (GBs) in wurtzite symmetry has also been carried out. In GaN, it is shown that the GBs are only made of separated a edge dislocations with 4, 5/7 and 8 atoms rings. For ZnO, a new structural unit: the [101 ̅0] edge dislocation made of connected 6-8-4-atom rings is reported for the first time, in agreement with an early theoretical report on dislocations and jogs in the wurtzite symmetry
Yehuwalashet, Ezra. "Gravity and Magnetic Survey, Modelling and Interpretation in the Blötberget Iron-Oxide Mining Area, Bergslagen, Sweden." Thesis, Uppsala universitet, Geofysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-305964.
Повний текст джерелаGruvområdet Blötberget som denna MSc avhandling är fokuserat kring ligger 230 km från Stockholm,12 km från Ludvika, i Bergslagen. Mineralförekomster, framförallt järnmalm (magnetit och hematit)har varit kända i området sedan 1600-talet, och storskalig brytning inleddes år 1944. Tidigare geologiskaundersökningar i området har gett detaljerad information om fyndighetens ytnära litologi och struktur.Hur långt ner förekomsten och moderbergarten sträcker sig har dock varit okänt. Som del av detnystartade projektet StartGeoDelineation utfördes marknära gravimetrimätningar. Totalt 180 mätpunkter,med ett medelavstånd av 150 m, samlades in under två fältkampanjer under 2015 och 2016.Vid modellering komplementades gravimetridata med magnetometridata, insamlad under flygmätningarutförda av Sveriges geologiska undersökningar (SGU). Efter noggrann bearbetning av gravimetridatatogs den kompletta bougeranomalin fram. Det uppskattade felet är ca 0.6 mGal och är till följd avosäkerhet i korrigeringar för drift hos instrument, dygnsvariation, geodesi och topografi. Efter korrigeringav regional trend (uppskattad från 2:a ordningens pylonom, och med satt skala av 8 mGal somresultat) gjordes en 3D modell, via inversionsalgoritmer, samt en tolkning. Det står klart av framförallti gravimetridatan att det finns två avvikande zoner. Dessa indikerar mineraliseringen och en gräns i densödra delen av undersökningsområdet med gravimetridata i låg respektive höga värde. Detta återspeglartroligtvis också en förkastningszon mellan två lithologiska enheter. I denna studie har enkla geometriskaformer och voxlar (mesh) använts för bådadera forward modellering och inversionsalgoritmer. Deursprungliga och referensmodellerna testades på både dataset för gravitmetri och magnetometri. Trotsatt modellerna fortfarande visar tvetydiga resultat så kan de ändå användas för att ge förslag på struktureroch läge för mineraliseringen, och skall även kunna användas för att uppskatta tonnage. Det sistnämndakunde dock inte uppnås då punktäthet i mätdatan, till följd av att det numera vattenfyllda dagbrottet intekunde inkluderas i mätområdet, och att formen av mineraliseringen inte kunde avgränsar på etttillfredsställande sätt. För en förbättring av resultaten bör fler mätpunkter till gravimetridata samlas in iområdet så att 3D-modelleringen kan förbättras genom upprepade justeringar av inversionsparametrarna
StartGeoDelineation
Penz, Sébastien. "Modélisation et inversion de données électriques en courant continu : vers une prise en compte efficace de la topographie." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00796438.
Повний текст джерелаCherevatova, M. (Maria). "Electrical conductivity structure of the lithosphere in western Fennoscandia from three-dimensional magnetotelluric data." Doctoral thesis, Oulun yliopisto, 2014. http://urn.fi/urn:isbn:9789526207100.
Повний текст джерелаTiivistelmä Olemme tutkineet litosfäärin sähkönjohtavuutta Fennoskandian länsiosassa magnetotelluurisen (MT) menetelmän avulla. Fennoskandian länsireuna muokkautui merkittävästi paleotsooisena aikana Kaledonidien vuorijonopoimutuksessa sekä myöhemmin mesotsooisena aikana Laurentia-mantereen repeytyessä ja Atlantin valtameren syntyessä noin 80 miljoonaa vuotta sitten. MT-tutkimukset tehtiin Etelä-Norjassa ja Fennoskandian luoteisosassa. Ensimmäisessä tutkimuksessa kallioperän sähkönjohtavuutta kuvattiin kaksiulotteisilla (2-D) johtavuusmalleilla, jotka ulottuvat Oslosta Norjan rannikolle. Mallien tulkinta viittaa siihen, että maan kuori on pääosin hyvin eristävä lukuun ottamatta muutamaa kuoren ylä- ja keskiosassa olevaa johdekerrosta. Yläkuoren johteet edustavat alunaliuskeita ja keskikuoren johteet todennäköisesti suljetuissa merialtaissa syntyneitä hiilipitoisia sedimenttikerrostumia. Laajempi MT-tutkimus tehtiin ”Magnetotellurics in the Scandes” -hankkeessa. Mittauksia tehtiin 279 mittauspisteessä kesinä 2011–2013. Saadun aineiston avulla voitiin laatia 2-D inversiomallit kuoresta ja ylävaipasta sekä 3-D inversiomalli kuoresta. Tulosten mukaan täällä kuoren yläosa on eristävä kun taas kuoren alaosa on sähköä hyvin johtava. Edellisen lisäksi malleissa näkyy yläkuoren johtavat muodostumat Skellefteån ja Kittilän alueilla, korkean johtavuuden alunaliuskeet Kaledonidien alueella sekä johde Lofoottien alla. Litosfäärin paksuus on noin 200 km mittausverkon pohjoisosassa ja noin 300 km lounaassa. Tämän mukaan litosfääri on paksuin varhaisproterotsooisen litosfäärin alueella, ei arkeeisen litosfäärin alueella vastoin yleistä hypoteesia. Tutkimuksen teoreettisessa osassa kehitettiin sähkömagneettiseen mallinnukseen uusi monitasoiseen diskretisointiin perustuva menetelmä. MT-aineiston 3-D käänteisongelman ratkaisu ja siihen liittyvä suora mallintaminen vaativat suuren laskennallisen kapasiteetin, koska havaintojen ja mallin kuvaamiseen tarvittavien parametrien määrä on erittäin suuri. Moniresoluutio-algoritmi perustuu siihen, että mallin hienojakoisempaa diskretisointia tarvitaan yleensä lähellä maan pintaa kun taas syvemmälle edettäessä, sähkömagneettisen aallon diffuusin etenemisen vuoksi, malli voi olla karkeampi. Tietokonesimulaatioiden mukaan suoritusaika on viidennes ja muistitarve kolmannes verrattuna tavanomaiseen suoran laskennan ”staggered grid” -diskretisointiin
Birrien, Florent. "Assimilation de données et inversion bathymétrique pour la modélisation de l'évolution des plages sableuses." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00870775.
Повний текст джерелаSmittarello, Delphine. "Propagation des intrusions basaltiques. Modélisation analogique et suivi temporel par inversion des données de déplacements Combining InSAR and GNSS to Track Magma Transport at Basaltic Volcanoes Magma propagation at Piton de la Fournaise From Joint Inversion of InSAR and GNSS." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAU033.
Повний текст джерелаWe study magma transport in the upper crust by propagation of a buoyancy-driven fluid-filled crack. Two schools of thought formalize the modelling of this phenomenon. They provide a framework to interpret either the geometrical aspects (shape, trajectory) when fluid viscosity is neglected, or the temporal aspect (flow velocity of the fluid) when, resistance to fracturation of the medium is neglected. We use two complementary approaches~: temporal in situ monitoring by inversion of displacement data and analogue modelling, in order to constrain both the geometry and the timing and to discriminate the field of application of each school of thought.We combine InSAR and GNSS data in an original inversion procedure, taking advantage of both the spatial coverage of InSAR and the temporal resolution of GNSS. The method is applied to study the complex propagation (changes of direction and velocity) that led to the eruption of 26 May 2016 at Piton de la Fournaise. This makes it possible to validate the method and provides new constraints on the supply and triggering of this eruption. In the laboratory, we are investigating the influence of fluid viscosity on the velocity and trajectory of a buoyancy-driven fluid-filled crack during ascent in the presence of a heterogeneous stress field. We used gelatine an analogue of elastic host-rock and we show that the addition of salt increases its resistance to fracture. We also show that the trajectory is the result of a competition between the internal pressure, the external stress field and the crack length. Finally, we highlight the influence of the properties of the medium, as well as those of the injected fluid on the propagation velocity and the velocity variations during ascent in the presence of a heterogeneous stress field
Dupuy, Bastien. "Propagation des ondes sismiques dans les milieux multiphasiques hétérogènes : modélisation numérique, sensibilité et inversion des paramètres poroélastiques." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00657366.
Повний текст джерелаPérez, Solano Carlos Andrés. "Imagerie sismique de la proche sub-surface : modification de l'inversion des formes d'onde pour l'analyse des ondes de surface." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2013. http://pastel.archives-ouvertes.fr/pastel-00932790.
Повний текст джерелаOzbek, Ibrahim Yucel. "Dynamic System Modeling And State Estimation For Speech Signal." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611777/index.pdf.
Повний текст джерелаGaussian mixture model (GMM) regression based inversion and Jump Markov Linear System (JMLS) based inversion. GMM regression based inversion method involves modeling audio (and /or visual) and articulatory data as a joint Gaussian mixture model. The conditional expectation of this distribution gives the desired articulatory estimate. In this method, we examine the usefulness of the combination of various acoustic features and effectiveness of various types of fusion techniques in combination with audiovisual features. Also, we propose dynamic smoothing methods to smooth articulatory trajectories. The performance of the proposed algorithm is illustrated and compared with conventional algorithms. JMLS inversion involves tying the acoustic (and/or visual) spaces and articulatory space via multiple state space representations. In this way, the articulatory inversion problem is converted into the state estimation problem where the audiovisual data are considered as measurements and articulatory positions are state variables. The proposed inversion method first learns the parameter set of the state space model via an expectation maximization (EM) based algorithm and the state estimation is handled via interactive multiple model (IMM) filter/smoother.
Vallot, Dorothée. "Modelling calving and sliding of Svalbard outlet glaciers : Spatio-temporal changes and interactions." Doctoral thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-334787.
Повний текст джерелаHassane, Mamadou Maina Fadji Zaouna. "Modélisation de la dynamique du transfert hydrique vers les aquifières : application à la détermination de la recharge par inversion dans un système hydrogéologique complexe." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH010/document.
Повний текст джерелаGroundwater is the main available water resource for many countries; they are mainly replenished by water from precipitation, called groundwater recharge. Due to its great importance, management of groundwater resources is more essential than ever, and is achieved through mathematical models which offer us a better understanding of physical phenomena as well as their prediction. Hydrogeological systems are generally complex thus characterized by a highly variable dynamic over time and space. These complexities have attracted the attention of many hydrogeologists and many sophisticated models that can handle these issues and describe these systems accurately were developed. Unfortunately, modeling groundwater recharge is still a challenge in groundwater resource management. Generally, groundwater models are used to simulate aquifers flow without a good estimation of recharge and its spatial-temporal distribution. As groundwater recharge rates show spatial-temporal variability due to climatic conditions, land use, and hydrogeological heterogeneity, these methods have limitations in dealing with these characteristics. To overcome these limitations, a coupled model which simulates flow in the unsaturated zone and recharge as well as groundwater flow was developed. The flow in the unsaturated zone is solved either with resolution of Richards equation or with empirical models while the diffusivity equation governs flow in the saturated zone. Robust numerical methods were used to solve these equations: we apply non-conforming finite element to solve the diffusivity equation and we used an accurate and efficient method for solving the Richards equation. [...]
Maurel, Gaëtan. "Simulations multi-échelles de matériaux polymères." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22512/document.
Повний текст джерелаPolymer materials are widely used, both for everyday applications and in high-technology products. These materials involves a wide range of time and length scales, making the modelling of their properties challenging by using only one method. This thesis focuses on the development of a multiscale strategy, combining different levels of description of the matter. The aim is to reach the rheological properties of a polymer over a large time scale, while retaining the chemical structure inherent of its microstructure. The investigation of structure-property relationships will then be facilitated. The mesoscopic potentials are developped from atomistic configurations. A quantitative reproduction of several structural properties of the polymer such as density or end to end distance is obtained. Then, the transferability of the potentials has been studied through the dependence of temperature, pressure or polymer structure on thermomechanical properties. By using these potentials, nonequilibrium simulations have been carried out to calculate the entanglement mass and the plateau modulus. The multicale approach has been extended to model the polymer-silica interaction in order to study the impact of the degree of confinement or the grafting density on the dynamical and structural properties of polymer chains close to the surface
Silvennoinen, H. (Hanna). "3D structure of the crust and upper mantle beneath Northern Fennoscandian shield." Doctoral thesis, University of Oulu, 2015. http://urn.fi/urn:isbn:9789526210681.
Повний текст джерелаLavoué, François. "Inversion des formes d'ondes électromagnétiques en 2D pour le géoradar : vers une imagerie multi-paramètre à partir des données de surface." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU050/document.
Повний текст джерелаThe quantitative characterization of the shallow subsurface of the Earth is a critical issue for many environmental and societal challenges. Ground penetrating radar (GPR) is a geophysical method based on the propagation of electromagnetic waves for the prospection of the near subsurface. With central frequencies between 10~MHz and a few GHz, GPR covers a wide range of applications in geology, hydrology and civil engineering. GPR data are sensitive to variations in the electrical properties of the medium which can be related, for instance, to its water content and bring valuable information on hydrological processes. In this work, I develop a quantitative imaging method for the reconstruction of 2D distributions of permittivity and conductivity from GPR data acquired from the ground surface. The method makes use of the full waveform inversion technique (FWI), originating from seismic exploration, which exploits the entire recorded radargrams and has been proved successful in crosshole GPR applications.In a first time, I present the numerical forward modelling used to simulate the propagation of electromagnetic waves in 2D heterogeneous media and generate the synthetic GPR data that are compared to the recorded radargrams in the inversion process. A frequency-domain finite-difference algorithm originally developed in the visco-acoustic approximation is adapted to the electromagnetic problem in 2D via an acoustic-electromagnetic mathematical analogy.In a second time, the inversion scheme is formulated as a fully multiparameter optimization problem which is solved with the quasi-Newton L-BFGS algorithm. In this formulation, the effect of an approximate inverse Hessian is expected to mitigate the trade-off between the impact of permittivity and conductivity on the data. However, numerical tests on a synthetic benchmark of the literature display a large sensitivity of the method with respect to parameter scaling, showing the limits of the L-BFGS approximation. On a realistic subsurface benchmark with surface-to-surface configuration, it has been shown possible to ally parameter scaling and regularization to reconstruct 2D images of permittivity and conductivity without a priori assumptions.Finally, the imaging method is confronted to two real data sets. The consideration of laboratory-controlled data validates the proposed workflow for multiparameter imaging, as well as the accuracy of the numerical forward solutions. The application to on-ground GPR data acquired in a limestone massif is more challenging and necessitates a thorough investigation involving classical processing techniques and forward simulations. Starting permittivity models are derived from the velocity analysis of the direct arrivals and of the reflected events. The estimation of the source signature is performed together with an evaluation of an average conductivity value and of the unknown antenna height. In spite of this procedure, synthetic data do not reproduce the observed amplitudes, suggesting an effect of the radiation pattern of the shielded antennae. In preliminary tests, the inversion succeeds in fitting the data in the considered frequency range and can reconstruct reflectors from a smooth starting model
Fachin, Sérgio Junior da Silva. "Ensaios geoelétricos 2D no antigo lixão de Ribeirão Preto-SP: avaliação de parâmetros de aquisição e monitoramento ambiental do problema." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/14/14132/tde-09112007-152210/.
Повний текст джерелаDue to the increasing concern with the environmental protection and preservation of the shallow water and groundwater aquifers quality, the areas of disposal of residues, have been special attention of the environmental protection agency. Currently the geoelectrical methods have been largely used as an investigation non-evasive methodology in affected areas by inadequate disposal of urban solid and industrial residues, because it provides information of the localization and geometrical characteristics of the waste disposal, contamination plume extent, saturated zone position, underground flow direction and geologic characteristic, if the techniques and the acquisition parameters are adequately chosen. The simulations and interpretation methods also assists during the characterization and environmental monitoring of landfill areas. The objective of this research was the evaluation of the acquisition field parameters (electrodes arrays, electrodes spacing and number of the investigations levels) and 2D investigations with the resistivity and induced polarization methods for characterization and environmental monitoring. This evaluation was carried through the use of 2D forward modeling and field investigations in old landfill site at Ribeirão Preto city, São Paulo, Brazil. The use of the forward modeling allowed to choose the best field acquisition parameters in accordance with the answers for the geologic-geophysical simulated model. The comparison between our results and previous results showed contamination marked for low electric resistivity values (1 ? 30 Ohm.m) and high chargeability values (15 ? 50 mV/V) and also that the tested parameters of acquisition in agreement with the results of the forward modeling. The Pole-dipole array (a= 5 meters and n= 10) show the best result (resolution image and investigation depth), forward modelling and field acquisition.
Ismail, Nazli. "Controlled Source Radiomagnetotelluric (CSRMT) Applications in Environmental and Resource Exploration." Doctoral thesis, Uppsala universitet, Geofysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-102750.
Повний текст джерелаLavergne, Fabien. "Méthodologie de synthèse de lois de commandes non-linéaires et robustes : application au suivi de trajectoire des avions de transport." Toulouse 3, 2005. http://www.theses.fr/2005TOU30248.
Повний текст джерелаThe work presented in this PhD thesis report is situated within the framework of the nonlinear and robust control of transport aircrafts. The purpose of this thesis is to couple the properties of nonlinear controllers (adaptation to the aircraft nonlinearities, explicit controllers synthesis, easy and decoupled setting once the synthesis is achieved, genericity of the obtained control laws) with essential robustness properties. Indeed, to guarantee the flight safety, both in manual handling and in automatic control, the control laws have to present strong robust stability and performances properties. After an introduction to the industrial and research context, a "techniques, methods and tools" part allows us to point out the thesis contributions in the nonlinear robust control and automatic modelling domains. The nonlinear robust control technique presented, called RMI control (for "Robust Multi-Inversion") is based on the now classical Nonlinear Dynamic Inversion (NDI) technique, notably studied at Airbus for some years (Fabrice VILLAUME, Jean DUPREZ), and is robustified by adding a complementary observation loop. We also present an automatic tool creating nonlinear, multivariable and embeddable models, as well as neural networks correlated methods. This tool is mandatory for the industrialization of our model-based flight control laws. Then the applicative part of the thesis underlines the specificities of the "aircraft" system and proposes flight control laws architectures, associated reference trajectories, and the advanced validation of the whole system by simulations performed on Airbus' certified simulator. Finally, after a conclusion on the main results and perspectives linked to the thesis, we propose annexes allowing to go further into the details of certain parts of our study
Laurent, Gautier. "Prise en compte de l'histoire géologique des structures dans la création de modèles numériques 3D compatibles." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0057/document.
Повний текст джерелаThe main approaches to the modelling of geological structures are mainly geometrical, static and deterministic. In other terms, their geometry and connections are determined by applying criteria based on the compatibility with available data in their current state. The evolution of the geological structures is only integrated indirectly by the modeller and the kinematical and mechanical compatibility of the produced models remain difficult to assess. This thesis explores different methods which aim at better including the evolution of geological structures in the modelling process. Three complementary approaches are developed. First, a kinematical fault operator based on a 3D curvilinear fault frame is presented. It aims at progressively deforming the structures surrounding faults. The second approach is based on a pseudo-mechanical deformation tool inspired form computer graphics, based on rigid elements. It is used to interactively editing the structures and approximately simulate their deformation history. The last proposal is to compute the paleo-geographical coordinates from the restoration of geological structures. This way, the heterogeneities are characterised based on paleo-geographic distances which are compatible with the structural, kinematical and mechanical hypotheses specified when building the geological model. These different contributions open numerous perspectives to better take into account the evolution of the geological structures when modelling the subsurface and its heterogeneities. They help us to increase the compatibility of geomodels and simplify the parameterization of geological deformation to facilitate the characterisation of geological structures by inverse approaches
Bonnaventure, Philip P. "High-resolution Permafrost Distribution Modelling for the Central and Southern Yukon, and Northwestern British Columbia, Canada." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19899.
Повний текст джерелаIzumi, Fábio. "Modelagem de células solares nMOS operando em regime de inversão induzido por cargas positivas na interface SiOxNy/Si." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-06122017-093253/.
Повний текст джерелаThe goal of the present work was the modeling of MOS solar cells operating in an inversion regime controlled by positively charged centers at the SiNxOy interface. This type of solar cell was recently manufactured for the first time in the activities developed in the group of Surfaces, Interfaces and Electrochemical Deposition (GSIDE) from LSI/PSI/EPUSP using ultra-thin gate dielectrics (~2nm). The recipe for the growth of ultra-thin dielectrics was developed to ensure reproducibility and uniformity of the dielectrics thickness over large areas of few square centimeters. Based on the experimental curves CxVg, GxVg e IxVg of the manufactured MOS solar cells, it was shown for cells manufactured in P-type substrate that there are K centers dominantly filled with positive charges in all operating regimes (accumulation, depletion and inversion). The positive charge density (Qiq) at the SiNxOy/Si interface, in addition to having a positive charge, presented a linear behaviour with the surface potential (ys) or with the gate voltage (Vg) according to the results obtained from a numerical simulator developed for this application. Such behavior consisted of accommodating the positive charges at the SiNxOy/Si interface so that a deep depletion region (Wd) is formed without the presence of the inversion layer in the condition without illumination. For MOS cells subjected to different levels of illumination, both for dielectrics grown at 850oC as well as for those grown at 700oC, it was found that the K centers at the SiNxOy/Si interface work as a region of positive charge storage as the electrons tunnel from the interface towards the metal gate of the MOS cells. As a result, this type of behaviour means a new way of implementing the photovoltaic effect.
Bellens, François. "Caractérisation et modélisation de canal intra-véhiculaire : communication ultra-large bande et retournement temporel." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209452.
Повний текст джерелаDoctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Mezquida, Alcaraz Eduardo José. "Numerical Modelling of UHPFRC: from the Material to the Structural Element." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/167017.
Повний текст джерела[CA] El principal objectiu de la present tesi es el desenvolupament d'una completa metodologia per al modelat numèric de l'UHPFRC des del nivell material fins arribar als elements estructurals. Es pretén contribuir a l'avanç del coneixement del comportament mecànic de l'UHPFRC per mitjà d'un procediment per al modelat numèric útil per al modelat i disseny estructural que permeta fer que aquest material siga competitiu al mercat de la construcció. En la metodologia de modelat proposta, es considera un comportament constitutiu de l'UHPFRC optimitzat per mitjà d'un procediment directe i fiable amb el qual s'aprofiten els avantatges del material, resultant en un disseny estructural eficient des del punt de vista mecànic i econòmic. És necessari produir SH-UHPFRC per a aconseguir grans propietats mecàniques? És possible generar SS-UHPFRC amb el qual queden reduïts els costs inicials mantenint unes propietats mecàniques i de durabilitat competitives que comporten un disseny estructural efectiu? El desenvolupament d'UHPFRC amb baix enduriment per deformació i de SS-UHPFRC pot reduir les seues propietats mecàniques però, si són adequadament estudiades i controlades, aquests podrien ser optimitzats. La tesi aborda algunes d'aquestes qüestions per mitjà de l'estudi del comportament a tracció de l'UHPFRC que va des de SH-UHPFRC fins SS-UHPFRC. Es pretén dur a terme una proposta de procediment fiable per a caracteritzar el comportament constitutiu a tracció i definir un model numèric d'elements finits fiable per a modelar amb precisió la resposta de provetes i elements estructurals armats d'UHPFRC. Per a definir el procediment directe per a caracteritzar a tracció tant SH-UHPFRC com SS-UHPFRC, s'ha dut a terme una campanya experimental i numèrica en la que s'ha analitzat el resultat d'assajar 227 provetes sense armadura fabricades amb UHPFRC amb quantitats de fibres curtes i llises d'acer de 120-130kg/m3 i 160kg/m3, assajades a flexió per mitjà de l'assaig a quatre punts (4PBT). El desenvolupament i la validació de l'esmentat procés són assegurats per mitjà d'un model no lineal d'elements finits (NLFEM) fiable. La validació numèrica duta a terme ha estat decisiva per a que aquest procediment siga precís, simple i fiable. Utilitzant aquesta campanya experimental, s'ha desenvolupat una aplicació predictiva per a estimar els paràmetres que defineixen el comportament constitutiu a tracció de l'UHPFRC. Aquesta aplicació és simple i directa i evita la possible variabilitat produïda per males interpretacions en l'aplicació del procés. A més a més, també s'ha dut a terme una segon campanya experimental constituïda per bigues d'UHPFRC armades a flexió amb diferents escales: 36 bigues curtes amb 130 i 160kg/m3 de fibres i dos bigues llargues de gran escala. Aquesta campanya s'ha modelat amb el NLFEM ací desenvolupat incloent efectes importants deguts a la interacció de l'UHPFRC amb les barres d'armat. Addicionalment, també s'han modelat amb el NLFEM tirants d'UHPFRC armats a tracció provinents d'una campanya experimental d'altra investigació. El model considera efectes deguts a la retracció, al 3D i comportament tensió stiffening que generen resultats molt precisos quan es comparen amb els resultats experimentals. Per tant, com a resultat de la present tesi doctoral, s'ha obtingut un model d'elements finits capaç de modelar amb precisió elements estructurals d'UHPFRC armats. Els resultats del model comparats amb els resultats experimentals no sols demostren la fiabilitat del NLFEM dut a terme sinó que també la coherència del procediment directe desenvolupat per a caracteritzar el comportament constitutiu a tracció de l'UHPFRC als dos casos, tant per a SH-UHPFRC com SS-UHPFRC, tant en elements estructurals armats a flexió com amb elements estructurals armats a tracció directa. Conseqüentment, s'ha proposat una metodologia completa i efectiva per al modelat numèric de l'UHPFRC des del niv
[EN] The main objective of the present PhD thesis is to develop a complete methodology for the numerical modelling of UHPFRC from the material level to structural elements. It intends to contribute to advanced knowledge of mechanical UHPFRC behaviour to lead to a numerically modelling proposal that is useful for structural modelling and design that allows options for this material to be competitive in the construction market. Optimised UHPFRC material constitutive behaviour, characterised by a direct reliable defined procedure, is considered in the proposed modelling methodology to take advantage of these properties, and to lead to an efficient structural design from the mechanical and economical points of view. Is it necessary to produce SH-UHPFRC to obtain excellent properties? Is it possible to develop SS-UHPFRC that leads to lower initial costs and to maintain competitive mechanical and durability properties that result in an effective structural design? The development of low strain-hardening and SS-UHPFRC would lead to reduce its mechanical properties, but they can be optimised if they are studied and controlled. The thesis addresses some of these questions by studying tensile UHPFRC behaviour to cover a wide range of tensile constitutive behaviours from SH-UHPFRC to SS-UHPFRC. It intends to propose a reliable tensile characterisation process and a reliable finite element model capable of accurately simulating the response of UHPFRC specimens and reinforced structural elements. An extensive experimental and numerical campaign with 227 unreinforced four-point bending test (4PBT) specimens with amounts of smooth-straight (13/0.20) steel fibres of 1.53-1.66% (120-130kg/m3) in volume and with 2.00% (160kg/m3), which represents SS-UHPFRC and SH-UHPFRC tensile behaviours, was carried out to set up a direct tensile characterisation procedure involving SS-UHPFRC and SH-UHPFRC. The direct procedure's development and validity are ensured by a reliable non-linear finite element model (NLFEM). Numerical validation was carried out and is decisive for performing the direct procedure to characterise the tensile behaviour of both SS and SH-UHPFRC herein developed accurately, simply and reliably. With the experimental programme herein, a predictive application for estimating tensile UHPFRC parameters was developed. The prediction offers reliable results. The application is simple and direct, and avoids variability in the characterisation procedure due to possible misinterpretations in its application. In addition, a second experimental programme, which includes reinforced concrete flexural beams on different scales, with 36 UHPFRC reinforced short beams with 130 and 160kg/m3 of steel fibres and two full-scale long beams, was carried out and modelled with the NLFEM herein developed including major effects due to the interaction between UHPFRC and reinforcement bars. Additionally, reinforced UHPFRC tensile bars from a recent experimental campaign performed by other researchers were modelled with the NLFEM. The model considers shrinkage effects, tension stiffening behaviour and 3D effects due to the particularities of the test, which provide very accurate results compared to those obtained with the experimental tests. As a result of this PhD thesis, an accurate NLFEM was obtained to model reinforced UHPFRC structural elements. The results of the model compared to the experimental ones demonstrate not only the reliability of the developed NLFEM, but also the coherence of the developed direct procedure to characterise tensile UHPFRC behaviour in both strain-softening and strain-hardening in reinforced flexural and direct tensile structural elements. Consequently, a complete and effective methodology for numerical UHPFRC modelling from the material level to structural elements is proposed.
Mezquida Alcaraz, EJ. (2021). Numerical Modelling of UHPFRC: from the Material to the Structural Element [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/167017
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