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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Baba Yaga: Character Design and Collectible Figurine

Adams, Ariel 01 May 2024 (has links) (PDF)
The first edition of a series holds value. It is a bookmark that holds a place in time that the artist can look back to and see the progress that led up to that point, as well as the continued progress that's been made after. Designing and creating a set of characters, bringing the main character through 3D modeling, and printing it has multiple uses in the industry. The techniques learned through this process have been used in toy design, stop-motion animation, museums, and medical applications. 3D printing is advancing and providing an opportunity to create high-definition models that can be reproduced quickly while maintaining their initial integrity. This paper will go through the model's design concept and how to execute it. It is also a culmination of all the traditional skills acquired from a fine art background combined with all the new skills learned in the digital media field. This project aims to create a cohesive set of 2D character concepts centered around the story By Command of the Prince Daniel (Nikolaevich, 1915). The main antagonist, Baba Yaga, was then brought through the 3D modeling process so she could be resin printed and turned into a collectible figurine. Descriptive character traits from her stories were reimagined while providing a unique approach to the design that still preserves the story's essence.
72

Baba Yaga - Right Side Portrait

Adams, Ariel 01 May 2024 (has links)
Preview image from Ariel Adam's Baba Yaga: Character Design and Collectible Figurine. / https://dc.etsu.edu/digitalmedia-culminating-experience-gallery/1000/thumbnail.jpg
73

2D and 3D-modelling as a support tool for aquifer mapping and large-scale knowledge transfer : Targeting safe aquifers in Towakull region inGowainghat Upazilla, Sylhet, Bangladesh / 2D och 3D-moellering som verktyg vid akvifärkartläggning och storskalig kunskapsöverföring

Dahl, Gustav January 2024 (has links)
Arsenic has been discovered in the groundwater of Bangladesh and affects millions of people. Many parts of the country experiences elevated levels of As above the drinking water limit set by Bangladesh at 50 μg/L. Tube wells installed at a shallow depth is the main source of drinking water in Bangladesh for local communities. Previous investigation has identified elevated levels of As in these shallow tube wells. Color of sediments as well as depth below surface was also identified as important properties in determining As safe aquifers. Despite the knowledge surrounding the elevated As concentrations and mitigation efforts there has been a lack of large scale, successful mitigation methods. The problems have been identified as a lack of large scale knowledge transfer regarding the subsurface geology to local drillers and communities as well as a lack of coherent and country wide data capturing, management and storage. The aim of this study was to investigate how already captured data in Bangladesh from previous projects could be compiled, formatted, visualized and communicated to facilitate large scale knowledge transfer as well as increasing the understanding off what geological and hydrogeological data is necessary to accurately and with a high degree of confidence map the aquifers of Bangladesh. This study was conducted as a pilot study for aquifer mapping in the EPSC-DDM project together with the International Groundwater Research Group at KTH. To understand data necessity and how to effectively map aquifers in Bangladesh data from various sources needed to be compiled. The data was cleaned and investigated as 2D and 3D models. Hydrographs was created from water level data in GeoGIS. Water quality data was used together in modelling processes and alone to investigate the water quality of potential aquifer systems. The modelling was conducted in GeoGIS for 2D cross sections and Earth Volumetric Studios for 3D models. The results showed two distinct aquifer in the study area of Towakull union, at a depth of 50-150 m as well as around 200-250 meters. The shallow aquifer was deemed unsafe in terms of As concentrations while the deep was deemed safe. The results from the modelling indicated that data already gathered for previous projects could be used as a base for aquifer mapping. Lithological data with main grain size together with water quality data at depth was deemed as the minimum data needed for 3D model aquifer mapping and water level data as well as color of the sediments was deemed as important data to collect if possible. The results also indicated that automatic capturing and storage of data into one coherent format would greatly decrease the time of data cleaning before modelling as well as increasing the accuracy and limiting the need for interpretation of the modeler. In conclusion the usage of 2D or 3D models for aquifer mapping shows great promise and the usage of already captured data to create these models was possible. The models had the potential to be easily communicated and distributed in digital format or in print to facilitate large scale knowledge transfer and increase evidence-based decision making in Bangladesh. / Arsenik (As) har upptäckts i grundvattnet i Bangladesh och påverkar tillgången till vatten för miljontals människor. Stora delar av landet har områden med förhöjda halter av As, över 50 μg/L vilket är den nationella gränsen för dricksvatten. Tidigare forskning har visat att rörbrunnar är den till störst del accepterade åtgärdsmetoden för As-säkert dricksvatten bland lokala aktörer, detta på grund av att de är billiga att installera och enkla att använda. Färg på sediment på det djup där filtret till brunnarna installeras har visats ge indikation på om grundvattnet har låga eller höga halter av arsenik. Holocena sediment är ofta grå till mörkt gråa och innehåller höga halter löst arsenik medan de röda eller bruna sediment som blivit exponerade och oxiderade har visat sig ha låga halter av löst arsenik. Även om problematiken och åtgärdsmetoder kring arsenikförorening av grundvattnet i Bangladesh är väl dokumenterade är det fortfarande stora delar av befolkningen som inte har tillgång till rent dricksvatten. Bristen på resultat i åtgärder tros vara avsaknaden av kunskapsdelning och utbildning av lokalbefolkningen, vilka ofta är de som borrar och använder rörbrunnarna, samt att det saknas ett nationellt övergripande format för insamling, lagring och användning av geologisk och hydrogeologisk data. Den här studien skrevs tillsammans med EPSC-DDM som är ett projekt mellan KTH, SIDA, UNICEF och DPHE i Bangladesh. Målet med studien var att undersöka vilken typ av geologisk samt hydrogeologisk data som kunde användas för akvifärkartläggning på lokal nivå i Bangladesh. Vidare var det av intresse att förstå på vilket sätt denna data skulle användas och kommuniceras för att kunna förmedla kunskapen till lokala aktörer. Det var av intresse att använda redan insamlad data i Bangladesh. Tillgänglig geologisk och hydrogeologiska data samlades in och modellerades i 2D och i 3D för att kartlägga akvifärer på lokal skala i Bangladesh. Programvaran GeoGIS användes för 2D modelleringen och Earth Volumetric Studios användes vid 3D modelleringen. Grundvattennivådata användes för att skapa hydrografer som kunde användas tillsammans med de tillverkade modellerna. Studieområdet var Towakull union i Gowainghat upazilla, norra Bangladesh. Studieområdet valdes på grund av tillgång till olika dataformat och källor. Resultatet av studien visade att det troligen fanns två distinkta akvifärer, vilket är en ansamling av grundvatten som kan användas som en vattenresurs, i Towakull, Bangladesh, vilket var området för pilotstudien. De aktuella akvifärerna låg på ett djup av 50–150 meter samt 200–250 meter. Den grunda akvifären visade sig innehålla förhöjda halter av arsenik och ansågs vara osäker att använda som dricksvattentäkt. Den djupa akvifären verkade vara frånskild den ovanliggande grunda akvifären och innehöll lägre nivåer av arsenik. Modelleringsprocessen visade att tidigare insamlad data kan användas på ett effektivt sätt för att kartlägga akvifärer i Bangladesh, både i 2D och i 3D. För 3D modellering visade det sig att geologiska data och vattenkvalité var nödvändigt för att få ett resultat som kunde ge information med tillräcklig precision för att stödja lokala aktörer i deras beslutsfattande. Hydrografer samt färg på sediment gav mer säkerhet i kartläggningen men bedömdes inte vara nödvändig om de inte skulle vara tillgängligt. Automatisk insamling av data bedöms underlätta vid modelleringsprocessen då en stor del av problemet var att ”rengöra” och formatera data från olika källor till liknande format. Detta steg kan till stor del undvikas om data samlas in och lagras automatiskt på samma sätt i hela Bangladesh. Sammanfattningsvis visade pilotstudien att 2D- och 3D modellering är effektiva verktyg för att kartlägga akvifärer i Bangladesh med hjälp av redan insamlad data. Litologisk data och vattenkvalitéan sågs vara nödvändig för modelleringsprocessen, sedimentfärg och hydrografer var kraftfulla hjälpmedel. Resultaten av modelleringen bedöms ha hög potential för att kunna förmedlas till lokala aktörer, i till exempel en liten utskriven sammanfattningsrapport. Att gå över till automatisk insamling och lagring av data är avgörande för att göra data tillgängligt och kvalitetssäkrad och således för att säkra modelleringsprocessens kvalitet och potential för uppskalning.
74

A theoretical model for the effectiveness of project-based learning in engineering design education

Gao, Mingyi January 2012 (has links)
The main focus of this thesis is on the effectiveness of project-based learning (PBL) in engineering design. The literature review has shown that there is much confusion and ongoing arguments concerning the implementation of PBL in engineering design, and there lacks consensus on its effectiveness. Little research has been done on providing measurable metrics of PBL effectiveness, not to mention discovering the optimal PBL and its underlying mechanisms based on solid educational theories and rigorous research methodology. In this thesis, the measurement of the optimal PBL effectiveness (effect) is studied and a theoretical model of PBL is built in order to identify parameters (cause) controlling the effectiveness and to study the interplay between effectiveness and the parameters. The model is built through three main phases, with a combination of qualitative and quantitative research methods. In phase one, the effectiveness of PBL is studied from the perspectives of the engineering design lecturers and engineering graduates by interviews, which is used to represent effect (Y axis) of the model. In phase two, on the basis of self-directed learning theory (SDL) and learner engagement theory,two key parameters of PBL, i.e. SDL and learner engagement, are identified and quantified respectively to represent cause (X axis) of the model. With the key parameters of PBL (X axis) and PBL effectiveness (Y axis) obtained, a theoretical model of PBL is proposed. The model is verified by means of experiments (student self-reported surveys). A specified Moving Average Method (MAM) is used for data analysis and findings demonstrate different trends of the relations between SDL and PBL effectiveness, and between learner engagement and PBL effectiveness. Consequently, a 3D model of PBL is built by combining the data in aforementioned 2D models,through which the optimal PBL effectiveness in 3D are identified and measured and the interplay between different parameters are found. In phase three, in order to find out more delicate features in PBL ignored by MAM, the dynamic interaction of individual differences in PBL teamwork is explored by the ethnological method (including participant observations and interviews), which is conducted as a supplement to the model of PBL. The theoretical model of PBL effectiveness proposed in this thesis is novel and groundbreaking. Firstly, a series of 2D and 3D models are presented and the relations between SDL, learner engagement and PBL effectiveness are revealed for the first time, which provides guidance for the optimal PBL measurement and implementation. Secondly, a qualitatively-quantitatively-combined strategy is used to discover the mechanisms controlling optimal PBL at different scales. Thirdly, the experiments verifying the model provide fresh quantitative insight into optimal PBL. In summary, the research in this thesis opens up a new research methodology for studying PBL effectiveness, which makes contribution to the educational field as well. Keywords: Project-based learning, Self-directed learning, Learner engagement, Optimal PBL effectiveness, 3D model, Individual differences, Engineering design, Pedagogy.
75

Novel 3D Head and Neck Cancer Model to Evaluate Chemotherapeutic Efficacy

Morgan, Kelly 01 January 2014 (has links)
HNSCC accounts for 7 percent of all new cancer occurrences. Despite currently available treatments, there continues to be a high mortality and recurrence rate in HNSCC. Well over 50 percent of all cancer patients receive chemotherapy as a standard treatment. However, only 5 percent of these cases have been shown to help with treatment of the disease. Formerly, two options were available for drug testing: in vivo animal models, and in vitro two-dimensional models. While in vivo models remain the most representative, their use is burdened by high costs, time constraints, and ethical concerns. 2D models are simple to use and cost effective, although they have been shown to produce inaccurate data regarding chemotherapeutic drug resistance due to their 2D arrangement and altered gene expression. Researchers for the past decade have been working to create 3D models that more accurately represent in vivo systems in order to evaluate chemotherapeutic efficacy and improve clinical outcomes. In line with this agenda, novel 3D head and neck cancer models were created out of electrospun synthetic polymers seeded with either HN6 or HN12 cancer cells. The models were then treated with chemotherapeutic drugs (either paclitaxel or cisplatin), and, after 72 hours, subjected to a live-dead assay in order to determine the cytotoxic effects of the drugs. 2D cultures of HN6 and HN12 were also and subject to a WST-1 assay after 72 hours. The results of the treated-scaffold assays were then compared to the results of the 2D culture assays, and, as predicted, the cancer cells in a 3D culture system proved to be more resistant to chemotherapeutic drugs. The underlying assumption for this study being that a 3D culture system based on precisely defined structural parameters would provide a practical environment to screen therapeutics for anti-cancer efficacy. To prove this, 3D scaffolds of three different fiber sizes were developed by electrospinning different concentrations of Poly(L-lactic acid) (“PLLA”) (55mg/ml, 115mg/ml, and 180mg/ml) onto a mandrel that was perforated to allow for increased porosity. The resultant small, medium, and large scaffolds were then subjected to concentrated hydrochloric acid (HCl) pretreatment in order to make them less hydrophobic. Different fiber diameters represented different ECM environments for both HN6 and HN12. It was proven that both cell types thrived best in small fibers (55mg/ml-115mg/ml) than in large fibers. It was also reaffirmed through live-dead anlaysis of cells seeded on 3D scaffolds and treated with IC90 values of cisplatin that the head and neck cancer cells were more resistant which is more representative to the 3D environment of cancer cells in vivo.
76

Compression progressive de maillages surfaciques texturés / Porgressive compression of surface textured meshes

Caillaud, Florian 17 January 2017 (has links)
Depuis plusieurs années, les modèles 3D deviennent de plus en plus détaillés. Cela augmente considérablement le volume de données les décrivant. Cependant, dans un même temps, un nombre croissant d’applications sont contraintes en mémoire et/ou en vitesse (visualisation sur périphériques mobiles, jeux vidéos, etc.). Dans un contexte Web, ces difficultés sont encore plus présentes. Cette situation peut entraîner des incompatibilités, des latences de transmission ou d’affichage qui sont souvent problématiques. La compression progressive de ces modèles est une des solutions envisageables. Le but étant de compresser les informations (géométrie, connectivité et attributs associés) de façon à pouvoir reconstruire progressivement le maillage. À la différence d’une compression dite single-rate, la compression progressive propose très rapidement un aperçu fidèle du modèle 3D pour ensuite le raffiner jusqu’à retrouver le maillage complet. Ceci permet un meilleur confort pour l’utilisateur et une adaptation de la quantité d’éléments à visualiser ou à traiter en fonction des capacités du périphérique de réception. Généralement, les approches existantes pour la compression progressive se focalisent sur le traitement de maillages 2-variétés triangulaires. Très peu de méthodes sont capables de compresser progressivement des maillages surfaciques non-variétés et, à notre connaissance, aucune ne permet de compresser génériquement un maillage surfacique quel que soit son type (i.e. non-variété et polygonal). Pour supprimer ces limitations, nous présentons une méthode de compression progressive générique permettant de traiter l’ensemble des maillages surfaciques (non-variétés et polygonaux). De plus, notre approche tient compte de l’attribut de texture potentiellement associé à ces maillages, en gérant correctement les coutures éventuelles. Pour ce faire, nous décimons progressivement le maillage à l’aide d’un nouvel opérateur générique de simplification. Cette décimation est guidée par une métrique locale qui a pour but de préserver la géométrie et la paramétrisation de la texture. Durant cette simplification, nous encodons progressivement les informations nécessaires à la reconstruction. Afin d’améliorer le taux de compression, nous mettons en oeuvre certains procédés de réduction de l’entropie, ainsi que des dispositifs de prédiction basés sur la géométrie pour l’encodage de la connectivité et des coordonnées de texture. Pour finir, l’image de texture est compressée progressivement puis multiplexée avec les données relatives au maillage. Ce multiplexage est réalisé à l’aide d’une métrique perceptuelle afin d’obtenir le meilleur rapport débit-distorsion possible lors de la décompression. / Since several years, 3D models become more and more detailed. This increases substantially the amount of data needed to describe them. However, in the same time, a rising number of applications are constrained in memory and/or in speed (mobile device visualization, video games, etc.). These difficulties are even more visible within a Web context. This situation can lead to incompatibilities, latency in transmission or rendering, which is generally an issue. The progressive compression of these models is a possible solution. The goal is to compress the information (geometry, connectivity and associated attributes) in order to allow a progressive reconstruction of the mesh. Contrary to a single-rate compression, progressive compression quickly proposes a faithful draft of the 3D model and, then, refines it until the complete mesh is recovered. This allows a better comfort for the user and a real adaptation of the rendered element number in adequacy with the terminal device properties. The existing approaches for progressive compression mainly focus on triangular 2- manifold meshes. Very few methods are able to compress progressively non-manifold surface meshes and, to our knowledge, none can deal with every surface meshes (i.e. nomanifold and polygonal), in a generic way. So as to suppress these limitations, we present a new generic progressive method allowing the compression of polygonal non-manifold surface meshes. Moreover, our approach takes care of the texture attribute, possibly associated to these meshes, by handling properly potential texture seams. For that purpose, we progressively decimate the mesh using a new generic simplification operator. This decimation is driven by a local metric which aims to preserve both the geometry and the texture parametrisation. During the simplification, we progressively encode the necessary information for the reconstruction. In order to improve the compression rate, we propose several entropy reduction mechanisms, as well as geometry based prediction strategies for the connectivity and UV coordinates encoding. Finally, the texture map is progressively compressed then multiplexed with mesh data. This multiplexing is achieved using a perceptual metric to provide the best rate-distortion ratio as possible during the decompression.
77

BIM Building Information Model : Hinder & Drivkraft

Govan, Ivan, Berisha, Burim January 2012 (has links)
The  construction  industry  is  a  costly  business  such  in  respect  of  capital  for  most construction defects which then require rework, tear down and rebuild again. This study is  meaningful  awareness  of  tools  that  can  reduce  this  best  through  communication  and information sharing between the parties.  The  construction  industry  is  known  as  temporary  projects  organizations,  where  the construction  project  consists  of  several  actors  who  have  to  communicate  and  share information  between  them  to  avoid  mistakes  later  in  the  build  time.  These  actors  are bounded together thus for the duration of the project, then broken when the project has reached its end. The challenge here is for these actors to apply a tool that can help and simplify communications, information sharing, and perhaps the most important aspect is to  create  a  routine  for  the  association  and  the  shattering  of  these  actors.  To  implement such  behavior  using  a  tool  such  as  BIM  in  the  industry  whose  size  perhaps  is indescribable may be a very hard task.  BIM (Building Information Model) could be seen as the solution to this problem because it  acts  as  a  portal  where  the  actors  involved  must  sign  in  and  communicate,  share information, and eventually create a behavior, a routine for this association and division of  the  actors  following  the  end  of  the  project.  The  technology  could  help  the  involved from  the  beginning  of  the  project,  already  in  the  model  stage,  break  down  and  prevent any construction barriers when the building has been placed in the works.  In the current situation used paper models, 2D models and three-dimensional models, 3D, where  the  last  one  is  a  part  of  the  BIM.  BIM  makes  it  also  possible  to  implement  4D, price  calculation  for  the  construction  from  beginning  to  end  and  5D  ie  construction details such as what kind of wood the door is made of, what kind of concrete it is, and even the amount of cable for the construction for example.  BIM  is  seen  as  a  information  technology  used  primarily  in  construction,  where  to encounter  several  obstacles  during  the  implementation  and  use  of  such  technology  is expensive  to  implement  in  a  small  operation,  but  it  creates  many  drivers,  many  agents that  have  implemented  BIM,  which  ultimately  pays  according  to  those  who  can  afford and in the current situation using it
78

3D Reconstruction and Modelling of the Sierras Exteriores Aragonesas (Southern Pyrenees, Spain). Structural Evolution of the Pico del Águila anticline

Vidal Royo, Oskar 23 June 2010 (has links)
This Thesis reports on the integration of different modelling techniques to construct a unified and better constrained conceptual model of structural evolution of the Pico del Águila anticline (External Sierras, Southern Pyrenees, Spain). The structure is a well-known example of detachment fold, which exhibits a N-S structural trend, parallel to the direction of tectonic transport in the Southern Pyrenees. Based on field observations of an unevenly distributed Triassic décollement, analogue modelling show how to generate orogen-perpendicular structures which may result in transverse anticlines. Numerical models investigate the effect of a complex mechanical stratigraphy, characterized by an interlayering of competent and incompetent layers, plus syn-kinematic sedimentation in the fold growth. Based on field data and seismic interpretations, a 3D reconstruction and sequential geomechanical restoration of the Pico del Águila anticline reports the coexistence of multiple folding mechanisms occurring simultaneously in different units and structural domains of the fold, leading to a complex strain pattern that can not be assessed by simplistic kinematic 2D approaches. By integrating the presented models with the previous data in the region, we discuss about the benefits and drawbacks of each modelling technique and present an integrated model of structural evolution for the Pico del Águila anticline. This brings a better comprehension of the structure as well as the processes that drove the evolution of the N-S detachment anticlines in the External Sierras of the Southern Pyrenees. / L’anticlinal del Pico del Águila és un conegut exemple de plec de desenganxament amb sedimentació marina a fluvio-deltaica associada, amb una tendència estructural N-S, paral•lela a la direcció de transport tectònic dels Pirineus Meridionals. Basat en observacions de camp que indiquen una distribució heterogènia del nivell de desenganxament Triàsic, els models analògics mostren el procés de generació d’estructures perpendiculars al sistema orogènic que poden donar lloc als anticlinals N-S descrits a les Sierras Exteriores Aragonesas. Els models numèrics investiguen l’efecte d’una estratigrafia mecànica complexa, caracteritzada per una intercalació d’unitats competents i incomptetents (amb marcades diferències en el grau de competència, per tant) i de la sedimentació sin-cinemàtica en el creixement i evolució de l’anticlinal. Basat en dades de camp i interpretacions de perfils sísmics s’ha portat a terme una reconstrucció i restitució geomecànica tridimensional de l’anticlinal del Pico del Águila. D’aquestes se’n deriva la coexistència de de múltiples mecanismes de plegament actuant simultàniament en diferents unitats i dominis estructurals, la qual implica al seu torn un patró i distribució de la deformació que no poden ser avaluats mitjançant aproximacions o tècniques de modelització cinemàtiques o/i bidimensionals. S’integren també els resultats obtinguts a partir de les esmentades tècniques de modelització amb les dades i coneixements previs de la regió, es discuteixen els beneficis, desavantatges i limitacions de cadascuna d’aquestes tècniques de modelització, i es presenta un model integrat d’evolució estructural del Pico del Águila. Aquest anàlisi crític dels resultats i aquest esforç d’integració porten sense dubte cap a una millor comprensió de l’estructura i dels processos que menaren l’evolució dels plecs de desenganxament N-S de les Sierras Exteriores Aragonesas dels Pirineus Meridionals.
79

Designing of A Pneumatic Cushion for Supporting Standing and Sitting Process

Yu, Mingyue, Lu, Yixuan January 2018 (has links)
As is known to all, the aging problem becomes more and more serious in recent years. The issues “get into and out of a chair”, from one of the self-care tasks of aging people named Functional mobility in ADLs (Activity of daily livings), need to be solved carefully in efficient ways to help seniors and patients who have physical problems dealing with their daily life. In this previous investigation, the existing products in the market are normally quite heavy and importable. After combined with the advantages of the existing products and some improvements in portability and comfort which is related to human engineering. A Pneumatic Cushion for Supporting Standing and Sitting Process, based on airbag and pneumatic system which has been designed in this thesis, can be used by user who has physical-trouble for standing up and sitting down. Meanwhile, after being assembled with some specific extra components, it can be used as a mobility aid device. For the whole designing process, many relevant article, video sources and websites are referred for the previous researches, including Google Scholar, BTH Digital Library and YouTube. The product was designed and analysed in Inventor 2018 and the fluid dynamic simulation has been done in Abaqus. Studies involved lifting function are selected after the survey about assist appliance and aid appliance market.
80

Métrologie par photogrammétrie aéroportée légère : application au suivi d'évolution de digues / Metrology with light aerial photogrammetry : application to dykes monitoring

Tournadre, Vincent 21 December 2015 (has links)
En embarquant un appareil photo grand public de bonne qualité sur un drone ou un ULM, il est aujourd'hui possible de réaliser de manière 100% automatique des modélisations 3D visuellement « parfaites » ou en tout cas suffisante tant que ce modèle est utilisé comme support de communication. Par contre, les performances de ces méthodes sont encore mal maîtrisées dans le contexte où l'on veut utiliser le modèle comme outil de mesure. Les géométries d'acquisition linéaires, propices aux dérives de bandes photogrammétriques, en sont un exemple représentatif. Un phénomène de courbure de bande est alors constaté, nécessitant un travail de mesure terrain conséquent pour être corrigé. Ces imprécisions limitent l'intérêt de telles acquisitions, et sont un défi pour la communauté des photogrammètres, le marché naissant du drone, mais aussi de multiples industriel ayant un intérêt fort pour des systèmes capables d'assurer un suivi de mouvement 3D des sols avec une précision de quelques millimètres (par exemple suivi de digues, érosion agraire, surveillance de réseaux ferrés,...). Cette thèse est un projet de recherche issu d'un partenariat entre l'Institut National de l'Information Géographique et Forestière (IGN), et la Compagnie Nationale du Rhône (CNR), concessionnaire chargé d'entretenir et surveiller le réseau de digues de retenue du fleuve. Il s'agit - à partir de moyens aériens légers - d'arriver à un système d'auscultation plus rapide, plus économique et offrant une géométrie plus fine que les systèmes topométriques utilisés actuellement. Nous présentons tout d'abord une étude comparative des moyens aériens légers, montrant l'intérêt et les limitations des drones face aux ULM. Nous proposons des procédures d'acquisition adaptées aux géométries étudiées, permettant de limiter de manière opérationnelle les dérives. Dans un second temps, nous montrons que les phénomènes de courbure sont liés à des modèles d'orientation internes inadaptés, et nous proposons une procédure d'auto-calibration en trois étapes. Nos essais menés sur des chantiers linéaires montrent que le calcul des orientations est sensiblement amélioré (d'écarts métriques à des écarts centimétriques). Dans un troisième temps, nous proposons une optimisation de la compensation sur les points d'appuis, permettant de diminuer le nombre de mesures nécessaires. Enfin, nous présentons des méthodes pour contrôler l'incertitude des modèles 3D générés, et à travers une analyse diachronique, des exemples de suivi d'évolution permettant de suivre finement l'évolution de tels ouvrages / By embarking a good quality consumer grade camera on an Unmanned Aerial Vehicle (UAV) or on an ultralight system, it is possible to create – fully automatically – 3D models that are visually ''perfect'', or at least sufficient for visual or communication purposes. However, the accuracy of these methods is still a concern, especially if the resulting models are to be used as measuring tools. Linear acquisitions – also known as corridor mapping – are a striking example of the uncontrolled error propagation. A bowl effect is often observed, requiring multiple ground measurements to be overcome. These effects restrict the interest of such acquisitions. They are a challenge for the photogrammetrists community, the emerging civil UAV market, as well as many industrials interested in systems able to monitor ground deformations with an accuracy within a few millimeters (railway network surveillance, erosion of agricultural land, embankments monitoring,…).This thesis is an applied research project, led with a river concessionary which has the responsibility to maintain and keep under surveillance its containment dykes network. The purpose is to use light aerial systems as a mean for a monitoring system which is faster, cheaper, and more detailed than the topometric solutions used so far. First of all, we present a comparative study to understand, between UAVs and ultralight system, which tool is the most adapted for a specific need. We propose refined acquisition procedures, than can be used to limit operationally the drifts. In a second phase, we identify the internal camera model as the weak link, and propose a three steps auto-calibration procedure. Our tests led on linear acquisitions demonstrate that the external orientations accuracy are noticeably improved (from decimetric or even metric disparities, reduced to a few centimeters or less). In a third part, we propose an optimization of the adjustment on the ground control points, which is a way to limit the amount of ground measurements necessary. Finally, we present methods to control 3D models uncertainty, and through a diachronic analysis, examples of how such data can be used to monitor such structures through time

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