Within this work an approach was developed, which utilises airborne laser scanner data in order to generate 3D building models. These 3D building models may be used for technical and environmental planning. The approach has to follow certain requirements such as working automatically and robust and being flexible in use but still practicable. The approach starts with small point clouds containing one building at the time extracted from laser scanner data set by applying a pre-segmentation scheme. The laser scanner point cloud of each building is analysed separately. A 2.5D-Delaunay triangle mesh structure (TIN) is calculated into the laser scanner point cloud. For each triangle the orientation parameters in space (orientation, slope and perpendicular distance to the barycentre of the laser scanner point cloud) are determined and mapped into a parameter space. As buildings are composed of planar features, primitives, triangles representing these features should group in parameter space. A cluster analysis technique is utilised to find and outline these groups/clusters. The clusters found in parameter space represent plane objects in object space. Grouping adjacent triangles in object space - which represent points in parameter space - enables the interpolation of planes in the ALS points that form the triangles. In each cluster point group a plane in object space is interpolated. All planes derived from the data set are intersected with their appropriate neighbours. From this, a roof topology is established, which describes the shape of the roof. This ensures that each plane has knowledge on its direct adjacent neighbours. Walls are added to the intersected roof planes and the virtual 3D building model is presented in a file written in VRML (Virtual Reality Macro Language). Besides developing the 3D building model reconstruction scheme, this research focuses on the geometric reconstruction and the derivation of attributes of 3D building models. The developed method was tested on different data sets obtained from different laser scanner systems. This study will also show, which potential and limits the developed method has when applied to these different data sets. / In der vorliegenden Arbeit wird eine neue Methode zur automatischen Rekonstruktion von 3D Gebäudemodellen aus Flugzeuglaserscannerdaten vorgestellt. Diese 3D Gebäudemodelle können in technischer und landschaftsplanerischer Hinsicht genutzt werden. Bezüglich der zu entwickelnden Methode wurden Regelungen und Bedingungen erstellt, die eine voll automatische und robuste Arbeitsweise sowie eine flexible und praktikable Nutzung gewährleisten sollten. Die entwickelte Methode verwendet Punktwolken, welche mittels einer Vorsegmentierung aus dem gesamten Laserscannerdatensatz extrahiert wurden und jeweils nur ein Gebäude beinhalten. Diese Laserscannerdatenpunktwolken werden separat analysiert. Eine 2,5D-Delaunay-Dreiecksvermaschung (TIN) wird in jede Punktwolke gerechnet. Für jedes Dreieck dieser Vermaschung werden die Lageparameter im Raum (Ausrichtung, Neigungsgrad und senkrechter Abstand der Ebene des Dreiecks zum Schwerpunkt der Punktwolke) bestimmt und in einen Parameterraum aufgetragen. Im Parameterraum bilden diejenigen Dreiecke Gruppen, welche sich im Objektraum auf ebenen Flächen befinden. Mit der Annahme, dass sich ein Gebäude aus ebenen Flächen zusammensetzt, dient die Identifizierung von Clustern im Parameterraum der Detektierung dieser Flächen. Um diese Gruppen/Cluster aufzufinden wurde eine Clusteranalysetechnik genutzt. Über die detektierten Cluster können jene Laserscannerpunkte im Objektraum bestimmt werden, die eine Dachfläche formen. In die Laserscannerpunkte der somit gefundenen Dachflächen werden Ebenen interpoliert. Alle abgeleiteten Ebenen gehen in den entwickelten Rekonstruktionsalgorithmus ein, der eine Topologie zwischen den einzelnen Ebenen aufbaut. Anhand dieser Topologie erhalten die Ebenen ?Kenntnis? über ihre jeweiligen Nachbarn und können miteinander verschnitten werden. Der fertigen Dachgestalt werden Wände zugefügt und das komplette 3D Gebäudemodell wird mittels VRML (Virtual Reality Macro Language) visualisiert. Diese Studie bezieht sich neben der Entwicklung eines Schemas zu automatischen Gebäuderekonstruktion auch auf die Ableitung von Attributen der 3D Gebäudemodellen. Die entwickelte Methode wurde an verschiedenen Flugzeuglaserscannerdatensätzen getestet. Es wird gezeigt, welche Potentiale und Grenzen die entwickelte Methode bei der Bearbeitung dieser verschiedenen Laserscannerdatensätze hat.

<p>Unmanned aerial vehicles (UAVs) equipped with imaging systems and integrated global navigation satellite system/inertial navigation system (GNSS/INS) are used for a variety of applications. Disaster relief, infrastructure monitoring, precision agriculture, and ecological forestry growth monitoring are among some of the applications that utilize UAV imaging systems. For most applications, accurate 3D spatial information from the UAV imaging system is required. Deriving reliable 3D coordinates is conditioned on accurate geometric calibration. Geometric calibration entails both spatial and temporal calibration. Spatial calibration consists of obtaining accurate internal characteristics of the imaging sensor as well as estimating the mounting parameters between the imaging and the GNSS/INS units. Temporal calibration ensures that there is little to no time delay between the image timestamps and corresponding GNSS/INS position and orientation timestamps. Manual and automated spatial calibration have been successfully accomplished on a variety of platforms and sensors including UAVs equipped with frame and push-broom line cameras. However, manual and automated temporal calibration has not been demonstrated on both frame and line camera systems without the use of ground control points (GCPs). This research focuses on manual and automated spatial and temporal system calibration for UAVs equipped with GNSS/INS frame and line camera systems. For frame cameras, the research introduces two approaches (direct and indirect) to correct for time delay between GNSS/INS recorded event markers and actual time of image exposures. To ensure the best estimates of system parameters without the use of ground control points, an optimal flight configuration for system calibration while estimating time delay is rigorously derived. For line camera systems, this research presents the direct approach to estimate system calibration parameters including time delay during the bundle block adjustment. The optimal flight configuration is also rigorously derived for line camera systems and the bias impact analysis is concluded. This shows that the indirect approach is not a feasible solution for push-broom line cameras onboard UAVs due to the limited ability of line cameras to decouple system parameters and is confirmed with experimental results. Lastly, this research demonstrates that for frame and line camera systems, the direct approach can be fully-automated by incorporating structure from motion (SfM) based tie point features. Methods for feature detection and matching for frame and line camera systems are presented. This research also presents the necessary changes in the bundle adjustment with self-calibration to successfully incorporate a large amount of automatically-derived tie points. For frame cameras, the results show that the direct and indirect approach is capable of estimating and correcting this time delay. When a time delay exists and the direct or indirect approach is applied, horizontal accuracy of 1–3 times the ground sampling distance (GSD) can be achieved without the use of any ground control points (GCPs). For line camera systems, the direct results show that when a time delay exists and spatial and temporal calibration is performed, vertical and horizontal accuracy are approximately that of the ground sample distance (GSD) of the sensor. Furthermore, when a large artificial time delay is introduced for line camera systems, the direct approach still achieves accuracy less than the GSD of the system and performs 2.5-8 times better in the horizontal components and up to 18 times better in the vertical component than when temporal calibration is not performed. Lastly, the results show that automated tie points can be successfully extracted for frame and line camera systems and that those tie point features can be incorporated into a fully-automated bundle adjustment with self-calibration including time delay estimation. The results show that this fully-automated calibration accurately estimates system parameters and demonstrates absolute accuracy similar to that of manually-measured tie/checkpoints without the use of GCPs.</p>

Corrosion of steel reinforcement has been identified as one of the major problems facing many existing reinforced concrete structures including bridges. The exposure to aggressive environmental conditions such as those with high concentrations of chloride ions due to the use of de-icing salt in cold regions or high concentrations of carbon dioxide due to increased greenhouse gas emissions, accelerate the initiation process of corrosion. As corrosion initiates, the structural performance in terms of load-carrying capacity, ductility, and service life deteriorate over time. Coupling the effect of reinforcement corrosion with service loads may further weaken the structural performance of reinforced concrete bridges due to the presence of transverse load-induced cracks. Accordingly, a research program was conducted to evaluate the structural performance of reinforced concrete beams subjected to coupled effects of service loads and reinforcement corrosion. The research project consisted of combined experimental and numerical investigations. The experimental phase consisted of tests of nine small-scale beams and six large-scale beams. The beams were designed, constructed, instrumented, and loaded under a four-point load test. The primary test variables were the applied corrosion current density, level of corrosion, and level of sustained loading as percentage of beam ultimate capacity (0% Pu, 40% Pu, and 60% Pu). The corrosion level of steel reinforcement was quantitatively assessed using gravimetric weight measurements and three-dimensional laser scanner technique. Test results indicated that failure of corroded RC beams was brittle due to premature rupture of corroded steel bars, which was attributed to the development of localized corrosion at the sections with flexural cracks in beams. Furthermore, it was found that beams subjected to higher levels of service loads, experienced further reductions in ultimate load capacity and ductility. In addition, tensile tests were used to evaluate the effect of corrosion on the mechanical performance of steel bars retrieved from the corroded beams. It was found that the tensile strength of corroded steel bars, based on nominal sectional area, was reduced with the increase of corrosion levels. In contrast, the tensile strength, based on minimum sectional area, was not influenced by the non-uniform distribution and localization of corrosion. In fact, there was a slight increase in strength with the increase of corrosion levels. The numerical phase consisted of finite element analyses of beams using DIANA FE analysis software. A simplified approach was implemented to introduce the damage induced by corrosion into two-dimensional nonlinear FE models, based on the experimental testing of corroded beams and corroded steel bars. The analyses were reasonably accurate in predicting cracking patterns, residual load capacity, residual ductility, and failure modes of corroded beams. Subsequently, the validated model was used to conduct a parametric study on the level of service loads, level of corrosion, strength of concrete, and tensile reinforcement ratio. It was found that the FE model of corroded beams was strongly influenced by the level of service loads, level of corrosion, and tensile reinforcement ratio.

Cette thèse avait deux buts principaux : a) l'implémentation et l'amélioration d'une méthode de calcul de densité volumique du sein (VBD), et b) la proposition d'une mesure d'irradiation utilisable pour l'évaluation du risque individuel en mammographie avec une méthode pour l'estimer. La densité du sein est connue comme indicateur de risque du cancer. Une méthode de quantification objective de la VBD a été développée, à partir d'approches existantes, et améliorée. La méthode a été implémentée pour deux systèmes de mammographie. Elle repose sur l'étalonnage du système de mammographie et la chaîne d'acquisition avec des fantômes équivalents aux tissus mammaires. Une carte de densité est calculée.La contribution majeure de la thèse consiste en une nouvelle méthode de validation, applicable à tout calcul de VBD d'image de mammographie. Elle consiste à comparer les résultats aux valeurs de densité obtenues par des scanners thoraciques pour la même patiente. Cette validation a été appliquée à notre méthode de calcul et nous avons trouvé 10% d'écart moyen entre les deux méthodes, ce qui est comparable aux résultats de l'état de l'art. Pour le risque d'irradiation individuel, nous proposons de remplacer la dose glandulaire moyenne par l'énergie déposée, qui dépend de la quantité et de la distribution du tissu glandulaire, qui est le tissu à risque. L'énergie volumique déposée est calculée par simulation de Monte Carlo. Le VBD, calculé pour l'image de projection à 0° en tomosynthèse, aide à localiser le tissu glandulaire et à attribuer l'énergie déposée dans les tissus différents. Une proposition a été faite pour des fantômes géométriques, un fantôme texturé et un cas de patiente / In this research project the main goals were a) to implement a method for the computation of the volumetric breast density (VBD), and b) to propose an improved quantity for the assessment of individual radiation-induced risk, in particular during mammography, together with a method to quantify it. The breast density is known as a breast cancer risk factor. The objective quantification of the volumetric breast density was developed, based on already published methods, and improved. The method was implemented for two mammography systems. It is based on the calibration of the mammography system acquisition chain with breast equivalent phantoms and computes a breast density map. Our most important contribution resides in a new validation method applicable to any VBD computation, consisting in comparing its results with the VBD obtained from a thorax CT examination for the same patient. This validation method was applied to our VBD computation. We found an average deviation between mammography and CT of less than 10%. Our results are comparable to the state-of-the-art results for other validation methods. For the individual radiation risk, we proposed to replace the average glandular dose by the imparted energy, which depends on the quantity and distribution of the glandular tissue, which is the tissue at risk. The volumetric imparted energy is computed from Monte Carlo simulations. The VBD, computed for the 0° projection of tomosynthesis exams, helps us to localize the glandular tissue and to attribute the imparted energy to the different tissues. A proposition was implemented for geometric phantoms, a textured phantom and a patient case.

This diploma thesis describes the design and implementation of appropriate procedure photogrammetry processing of technical documentation of selected historical artifacts gauges. This thesis deals with finding the most suitable evaluation of the calibration of the camera used for metric artifacts documentation, processing documentation and model visualization.

No description available.

Increasing awareness of sustainability in the concrete industry forces structural design and executionto focus on avoiding costly and unpredictable maintenance action, instead paying higher attention todamage prevention by direct actions on early stages of production. One of such approaches, whichdeals with the problem of freezing and thawing deterioration, is intentional air bubble introductionto the concrete mix. However, the mechanism of air entrainment in concrete can be negativelyaffected on different stages of production by many factors including cement type, admixture dosage,casting conditions or mixing procedure. Therefore, reliable tools for the end-product evaluationought to be considered. The experimental study, presented in this work, focuses on understandingthe blast furnace slag (BFS) influence as well as admixtures’ dosage effect on pore structure ofhardened concrete. Three types of cement were evaluated, including ordinary portland cement(OPC) and two types of CEM III cements with different BFS percentage. The optimal amountsof air entraining agent (AEA) and super plasticizer (SP) were chosen and later reduced in orderto evaluate their impact on total air content, spacing factor and specific surface of the air voids.The main method chosen for this evaluation was the use of an office flat-bed scanner to acquireimages and application of BubbleCounter software for the analysis of the air void structure. Thisapproach is based on linear traverse method and requires special surface treatment for contrastenhancement. Specimens for the analysis were cut from hardened concrete cubes and polishedto achieve a flat surface. The samples were later treated with black ink and zinc oxide paste toachieve a clear contrast between white voids and black paste/aggregate area. In order to estimatethe accuracy of this method, more conventional tools such as pressurised gauge method and air voidanalyser were applied for comparison. Resulted mixtures showed significant differences in air voidproperties between OPC and BFS containing concrete, with the latter being less affected by AEAdosage reduction. Changes in spacing factor and specific surface were also registered; however,their deterioration did not follow the same pattern as that of total air content. No significantdeviation between the two cements containing BFS was observed. An interesting effect of the usedpolycarboxylate ether SP on the AEA reactivity was registered, showing deterioration of air voidproperties with the decrease of plasticizer amount. Comparison of the results from different air voidanalysis methods, suggested an overall agreement on the measured air void system changes due tochanging the AEA content. However, the BubbleCounter software tended to slightly overestimatethe material’s resistance to freeze and thaw phenomenon, giving the most optimistic values inspacing factor and specific surface of air voids. / Betongindustrins ökande medvetenhet om hållbarhet leder till att man inom dimensionering ochutförande fokuserar mot att undvika kostnadskrävande och oförutsedda underhållsåtgärder ochistället lägga större vikt på att förebygga skador i produktionens tidiga skeden. En av dessaåtgärder, som hanterar problemet frostnedbrytning, är en medveten inblandning av luftbubblor ibetongen. Mekanismen för att skapa luftporssystemet kan emellertid bli negativt påverkad underolika skeden av produktionen av många faktorer såsom cementtyp, tillsatsmedelsdos, gjutvillkoroch blandningsordning. Därför behöver man reflektera över pålitliga verktyg för utvärderingenav slutprodukten. Den experimentella studien, som presenteras i detta arbete, fokuserar motförståelse hur slagg och tillsatsmedelsdos påverkar den hårdnade betongens luftporssystem. Tretyper av cement utvärderades, dels ett normalt portlandcement, dels två typer av CEM III-cementmed olika andelar av slagg. Optimala mängder av luftporbildare och flyttillsatsmedel valdesmen reducerades senare för att undersöka deras inverkan på totalt luftinnehåll samt luftporernasavståndsfaktor och specifika yta. Den huvudsakliga metoden som valdes för denna utvärderingvar en flatbäddsscanner (kontorsmodell) för att ta bilder och användningen av en programvaravid namn BubbleCounter för att analysera luftporssystemet. Detta tillvägagångssätt baseras påanalys av tvärgående linjer och kräver en speciell behandling av ytan för att åstadkomma kontraster.Provkroppar för analysen sågades ut ur hårdnade betongkuber och polerades för att erhålla en jämnyta. Provkropparna var senare behandlade med svart bläck och zinkoxidpasta för att åstadkomma entydlig kontrast mellan de vita porerna och den svarta ytan av cementpasta och ballast. För att studeranoggrannheten hos denna metod användes som jämförelse även mer konventionella metoder sommätningar med trycksatta givare och luftporsanalys. De framtagna blandningarna visade signifikantaskillnader i luftporernas egenskaper mellan betong med normalt portlandcement och betong medslaggcement, där den senare påverkades i mindre grad av reduktioner i dosen luftporbildare.Förändringar I avståndsfaktor och specifik yta noterades också men försämringen följde inte sammamönster som den för totala luftinnehållet. Ingen signifikant skillnad mellan de två cementeninnehållande slagg kunde observeras. En intressant inverkan av det använda polykarboxylateterbaseradeflyttillsatsmedlet på luftporbildarens reaktivitet noterades. Den visade en försämringav luftporernas egenskaper vid en reduktion av mängden flyttillsatsmedel. En jämförelse avresultaten från de olika metoderna för luftporsanalys indikerade en övergripande överensstämmelsegällande de uppmätta luftporssystemens förändring p.g.a. förändringar i mängden luftporbildare.Programvaran BubbleCounter tenderade emellertid att något överskatta materialets motstånd motfrostnedbrytning med de mest optimistiska värdena för luftporernas avståndsfaktor och specifikayta.

Humanity has always wanted to explore the world we live in and answer different questions about our universe. After the International Space Station will end its service one possible next step could be a Moon Outpost: a convenient location for research, astronaut training and technological development that would enable long-duration space. This location can be inside one of the presumed lava tubes that should be present under the surface but would first need to be inspected, possibly by machine capable of capturing and relaying a map to a team on Earth.In this report the past and future Moon base missions will be summarized considering feasible outpost scenarios from the space companies or agencies. and their prospected manned budget. Potential mission profiles, objectives, requirements and constrains of the BATonomous Moon cave Explorer (BAT-ME) mission will be discussed and defined. Vehicle and mission concept will be addressed, comparing and presenting possible propulsion or locomotion approaches inside the lava tube.The Inkonova “Batonomous™” system is capable of providing Simultaneous Localization And Mapping (SLAM), relay the created maps, with the possibility to easily integrate the system on any kind of vehicle that would function in a real-life scenario.Although the system is not fully developed, it will be assessed from a technical perspective, and proper changes for a viable system transition for the space-Moon environment will be devised. The transition of the system from the Batonomous™ state to the BAT-ME required state will be presented from the requirement, hardware, software, electrical and operational point of view.The mission will be devised into operational phases, with key goals in mind. Two different vehicles will be presented and designed on a high engineering level. A risk analysis and management system will be made to understand the possible negative outcomes of different parts failure on the mission outcome.

[pt] Esta pesquisa apresenta novas perspectivas para o desenvolvimento de objetos de vestuário a partir da aplicação de tecnologias digitais de produção. Aborda-se a transição do processo de fabricação sob medida para a produção em massa, e as etapas de produção industrial de um objeto de vestir. Explora-se o processo de digitalização corporal 3D, ferramenta que integra um novo modelo de manufatura com base na individualização; a modelagem paramétrica, baseada em algoritmos; e o potencial da manufatura aditiva. Para isso, foram realizadas atividades experimentais, que incluíram o estudo de uma palmilha anatômica, a parametrização de moldes base de saia e de blusa, e ainda a criação de um têxtil impresso a partir do processo FDM, com filamento flexível. / [en] This research presents new perspectives for clothing pieces development by the application of digital production technologies. It addresses the transition from custom-made to mass-production manufacturing, bringing into viewchanges in industrial production line. It explores 3D body scanning, a tool that assists a new manufacturing model based on individualization; parametric modeling, based on algorithms; and the potential of additive manufacturing. Experimental designs were carried out, including the study of an anatomical insole, the parametrization of skirt and blouse pattern, and a textile printed in flexible filament with FDM technology.

No description available.