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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.
151

Artificial Neural Networks in Greenhouse Modelling

Miranda Trujillo, Luis Carlos 24 August 2018 (has links)
Moderne Präzisionsgartenbaulicheproduktion schließt hoch technifizierte Gewächshäuser, deren Einsatz in großem Maße von der Qualität der Sensorik- und Regelungstechnik abhängt, mit ein. Zu den Regelungsstrategien gehören unter anderem Methoden der Künstlichen Intelligenz, wie z.B. Künstliche Neuronale Netze (KNN, aus dem Englischen). Die vorliegende Arbeit befasst sich mit der Eignung KNN-basierter Modelle als Bauelemente von Klimaregelungstrategien in Gewächshäusern. Es werden zwei Modelle vorgestellt: Ein Modell zur kurzzeitigen Voraussage des Gewächshausklimas (Lufttemperatur und relative Feuchtigkeit, in Minuten-Zeiträumen), und Modell zur Einschätzung von phytometrischen Signalen (Blatttemperatur, Transpirationsrate und Photosyntheserate). Eine Datenbank, die drei Kulturjahre umfasste (Kultur: Tomato), wurde zur Modellbildung bzw. -test benutzt. Es wurde festgestellt, dass die ANN-basierte Modelle sehr stark auf die Auswahl der Metaparameter und Netzarchitektur reagieren, und dass sie auch mit derselben Architektur verschiedene Kalkulationsergebnisse liefern können. Nichtsdestotrotz, hat sich diese Art von Modellen als geeignet zur Einschätzung komplexer Pflanzensignalen sowie zur Mikroklimavoraussage erwiesen. Zwei zusätzliche Möglichkeiten zur Erstellung von komplexen Simulationen sind in der Arbeit enthalten, und zwar zur Klimavoraussage in längerer Perioden und zur Voraussage der Photosyntheserate. Die Arbeit kommt zum Ergebnis, dass die Verwendung von KNN-Modellen für neue Gewächshaussteuerungstrategien geeignet ist, da sie robust sind und mit der Systemskomplexität gut zurechtkommen. Allerdings muss beachtet werden, dass Probleme und Schwierigkeiten auftreten können. Diese Arbeit weist auf die Relevanz der Netzarchitektur, die erforderlichen großen Datenmengen zur Modellbildung und Probleme mit verschiedenen Zeitkonstanten im Gewächshaus hin. / One facet of the current developments in precision horticulture is the highly technified production under cover. The intensive production in modern greenhouses heavily relies on instrumentation and control techniques to automate many tasks. Among these techniques are control strategies, which can also include some methods developed within the field of Artificial Intelligence. This document presents research on Artificial Neural Networks (ANN), a technique derived from Artificial Intelligence, and aims to shed light on their applicability in greenhouse vegetable production. In particular, this work focuses on the suitability of ANN-based models for greenhouse environmental control. To this end, two models were built: A short-term climate prediction model (air temperature and relative humidity in time scale of minutes), and a model of the plant response to the climate, the latter regarding phytometric measurements of leaf temperature, transpiration rate and photosynthesis rate. A dataset comprising three years of tomato cultivation was used to build and test the models. It was found that this kind of models is very sensitive to the fine-tuning of the metaparameters and that they can produce different results even with the same architecture. Nevertheless, it was shown that ANN are useful to simulate complex biological signals and to estimate future microclimate trends. Furthermore, two connection schemes are proposed to assemble several models in order to generate more complex simulations, like long-term prediction chains and photosynthesis forecasts. It was concluded that ANN could be used in greenhouse automation systems as part of the control strategy, as they are robust and can cope with the complexity of the system. However, a number of problems and difficulties are pointed out, including the importance of the architecture, the need for large datasets to build the models and problems arising from different time constants in the whole greenhouse system.
152

Modellierung und Evaluierung von Multiagentensystemen im Kontext von Kooperationsproblemen / Modelling and analysis of multiagent systems concerning cooperation problems

Reinhold, Thomas 28 February 2005 (has links) (PDF)
The subject of this diploma thesis is the modelling and the analysis of mechanisms that enable multiagentsystems to establish communication relations and using them to control the interaction. With regards to the emergence of such symbol systems one groundwork of this paper is the realization that coordination problems aren't applicative to advance to evolution of "higher communication capabilities". With this in mind, this analysis uses a class of problems with explicit conflicts of interests between agents and the necessity of solving such interaction problems with the help of communication. The paper determines and discusses mechanisms and constraints that enable multiagentsystems to evolve such self-organisating social structures as well as preserving them. / Thema dieser Diplomarbeit ist die Modellierung und Untersuchung von Mechanismen, auf deren Grundlage Multiagentensysteme in der Lage sind, Kommunikationsbeziehungen aufzubauen und kommunikative Akte interaktionssteuernd zu verwenden. Hinsichtlich der Emergenz derartiger Symbolsysteme besteht eine wesentliche Erkenntnis, auf der diese Arbeit aufbaut, darin, dass Koordinationsprobleme als Kontext für MAS kein geeignetes experimentelles Umfeld für die Herausbildung "höherer kommunikativer Fähigkeiten" darstellen. Davon ausgehend werden für eine Klasse von Problemen, in denen die Abstimmung über eine Interaktion aufgrund von Interessenkonflikten einen expliziten Teil des kommunikativ zu lösenden Problems darstellt, Mechanismen und Constraints herausgearbeitet und diskutiert, die Agenten in die Lage versetzen, ein sich selbst organisierendes soziales Gefüge aufzubauen und zu erhalten.
153

Modellierung und Evaluierung von Multiagentensystemen im Kontext von Kooperationsproblemen: Modellierung und Evaluierung von Multiagentensystemen im Kontext von Kooperationsproblemen

Reinhold, Thomas 01 August 2004 (has links)
The subject of this diploma thesis is the modelling and the analysis of mechanisms that enable multiagentsystems to establish communication relations and using them to control the interaction. With regards to the emergence of such symbol systems one groundwork of this paper is the realization that coordination problems aren't applicative to advance to evolution of "higher communication capabilities". With this in mind, this analysis uses a class of problems with explicit conflicts of interests between agents and the necessity of solving such interaction problems with the help of communication. The paper determines and discusses mechanisms and constraints that enable multiagentsystems to evolve such self-organisating social structures as well as preserving them. / Thema dieser Diplomarbeit ist die Modellierung und Untersuchung von Mechanismen, auf deren Grundlage Multiagentensysteme in der Lage sind, Kommunikationsbeziehungen aufzubauen und kommunikative Akte interaktionssteuernd zu verwenden. Hinsichtlich der Emergenz derartiger Symbolsysteme besteht eine wesentliche Erkenntnis, auf der diese Arbeit aufbaut, darin, dass Koordinationsprobleme als Kontext für MAS kein geeignetes experimentelles Umfeld für die Herausbildung "höherer kommunikativer Fähigkeiten" darstellen. Davon ausgehend werden für eine Klasse von Problemen, in denen die Abstimmung über eine Interaktion aufgrund von Interessenkonflikten einen expliziten Teil des kommunikativ zu lösenden Problems darstellt, Mechanismen und Constraints herausgearbeitet und diskutiert, die Agenten in die Lage versetzen, ein sich selbst organisierendes soziales Gefüge aufzubauen und zu erhalten.
154

Strategische Interaktion realer Agenten: ganzheitliche Konzeptualisierung und Softwarekomponenten einer interdisziplinären Forschungsinfrastruktur

Tagiew, Rustam 11 February 2011 (has links)
Zum Verständnis menschlichen sozialen, administrativen und wirtschaftlichen Verhaltens, das als Spiel bzw. strategische Interaktion aufgefasst werden kann, reichen die rein analytischen Methoden nicht aus. Es ist nötig, Daten menschlichen strategischen Verhaltens zu sammeln. Basierend auf Daten lässt sich solches Verhalten modellieren, simulieren bzw. vorhersagen. Der theoretische Teil der Zielsetzung wird über praxisorientierte Konzeptualisierung strategischer Interaktion realer Agenten - Menschen und Maschinen - und gegenseitige Integration der Konzepte aus Spieltheorie und Multiagentensysteme erreicht, die über die bisherigen Ansätze hinausgehen. Der praktische Teil besteht darin, ein allgemein verwendbares System zu entwerfen, das strategische Interaktionen zwischen realen Agenten mit maximalen wissenschaftlichen Nutzen durchführen kann. Die tatsächliche Implementation ist eines der Ergebnisse der Arbeit. Ähnliche vorhandene Systeme sind GDL-Server (für Maschinen) [Genesereth u.a., 2005] und z-Tree (für Menschen) [Fischbacher, 2007]. Die Arbeit ist in drei Bereiche unterteilt - (1) Entwicklung von Sprachen für die Beschreibung eines Spiels, (2) ein auf diesen Sprachen basierendes Softwaresystem und (3) eine Offline-Analyse der u.a. mit dem System bereits gesammelten Daten als Beitrag zur Möglichkeiten der Verhaltensbeschreibung. Die Innovation dieser Arbeit besteht nicht nur darin ,einzelne Bereiche mit einander zu kombinieren, sondern auch Fortschritte auf jedem Bereich für sich allein zu erreichen. Im Bereich der Spielbeschreibungssprachen, werden zwei Sprachen - PNSI und SIDL - vorgeschlagen, die beide Spiele bei imperfekter Information in diskreter Zeit definieren können. Dies ist ein Fortschritt gegenüber der bisherigen Sprachen wie Gala und GDL. Speziell die auf Petrinetzen basierende Sprache PNSI kann gleichermaßen für Gameserver und für spieltheoretische Algorithmen von z.B. GAMBIT verwendet werden. Das entwickelte System FRAMASI basiert auf JADE [Bellifemine u.a., 2001] und ist den bisherigen Client-Server-Lösungen durch Vorteile der Multiagentensysteme voraus. Mit dem entstandenen System wurde bereits ein Experiment entsprechend den Standards der experimentellen Spieltheorie durchgeführt und somit die Praxistauglichkeit nachgewiesen. Das Experiment hatte als Ziel, Daten zur menschlichen Unvorhersagbarkeit und zur Vorhersagefähigkeit anderer zu liefen. Dafür wurden Varianten von \"Knobeln\" verwendet. Die Daten dieses Experiments sowie eines Experiments einer externen Arbeitsgruppe mit ähnlicher Motivation wurden mit Hilfe von Datamining analysiert. Dabei wurden die in der Literatur berichteten Gesetzmäßigkeiten des Verhaltens nachgewiesen und weitere Gesetzmäßigkeiten entdeckt.:Einführung Grundlagen Verwandte Arbeiten Sprachen für Spielbeschreibung Implementation der Spielinfrastruktur Beschreibung Strategischen Verhaltens Resümee Ergebnisse Ausblick / To understand human social, administrative and economic behavior, which can be considered as a game or strategic interaction, the purely analytical methods do not suffice. It is necessary to gather data of human strategic behavior. Based on data, one can model, simulate and predict such behavior. The theoretical part of the objective is achieved using a practice oriented conceptualization of the real agents\' - humans and machines - strategic interaction and mutual integration of the concepts from game theory and multi-agent systems, which go beyond the related work. The practical part is the design of an universally usable system that can perform the strategic interactions between real agents with maximum scientific benefit. The current implementation is one of the results of the work. Similar existing systems are GDL-server (for machines) [Genesereth et al., 2005] and z-Tree (for humans) [Fischbacher, 2007]. The work is divided in three fields - (1) development of languages for the description of a game, (2) a software system based on these languages and (3) an offline analysis of the data already gathered among other things using the system as a contribution to behavior definition facilities. The innovation of this work does not consist only in combining of the several fields to each other, but also in achieving of improvements in every field on its own. In the field of game definition languages, two languages are proposed - PNSI and SIDL, which both can define games of imperfect information in discrete time. It is an improvement comparing with hitherto languages as Gala and GDL. Especially, the Petri net based language PNSI can likewise be used for game servers and game theoretic algorithms like GAMBIT. The developed system FRAMASI is based on JADE [Bellifemine et al., 2001] and is ahead of the hitherto client-server solutions through the advantages of the multi-agent systems. Using the originated system, an experiment has been conducted according to the standards from the experimental game theory, and thus demonstrated the practicability. The experiment had the objective to provide data on the human unpredictability and the ability to predict others. Therefore, variants of Roshambo were used. The data from this experiment and from an experiment of an external workgroup with a similar motivation were analyzed using data mining. As results, the regularities of the behavior reported in literature have been demonstrated and further regularities have been discovered.:Einführung Grundlagen Verwandte Arbeiten Sprachen für Spielbeschreibung Implementation der Spielinfrastruktur Beschreibung Strategischen Verhaltens Resümee Ergebnisse Ausblick
155

Smart Software Engineering - Gestaltung agiler Methoden und Technologien zur Verbesserung der Softwareentwicklungsprozesse mittelständischer Systemhäuser

Barenkamp, Marco 19 April 2021 (has links)
Im Rahmen der Dissertation wurden die Wechselwirkungen, mögliche Potenziale und Herausforderungen von agilen Prinzipien im Hinblick auf IoT– und KI–Anwendungen auf den Softwareentwicklungsprozess in mittelständischen Unternehmen untersucht. Dazu wurde primär dem gestaltungsorientierten Forschungsparadigma, welches von besonderer Relevanz für die konstruktionsorientierte deutsche Wirtschaftsinformatik ist, gefolgt. Ein Primärziel dieses Forschungsvorhabens war die theoretische Herleitung agiler Methoden und Technologien zur Verbesserung der Software–Engineering–Prozesse mittelständischer Systemhäuser sowie die empirische Validierung und kritische Betrachtung dieser Technologien und Methodiken anhand ausgewählter, repräsentativer Fallbeispiele. Das zweites Primärziel der Dissertation ist die Forschungsarbeit an KI–Systemen, insbesondere im Rahmen von IoT–Anwendungen unter Berücksichtigung der möglichen Wechselwirkungen.
156

Interactive 3D Reconstruction / Interaktive 3D-Rekonstruktion

Schöning, Julius 23 May 2018 (has links)
Applicable image-based reconstruction of three-dimensional (3D) objects offers many interesting industrial as well as private use cases, such as augmented reality, reverse engineering, 3D printing and simulation tasks. Unfortunately, image-based 3D reconstruction is not yet applicable to these quite complex tasks, since the resulting 3D models are single, monolithic objects without any division into logical or functional subparts. This thesis aims at making image-based 3D reconstruction feasible such that captures of standard cameras can be used for creating functional 3D models. The research presented in the following does not focus on the fine-tuning of algorithms to achieve minor improvements, but evaluates the entire processing pipeline of image-based 3D reconstruction and tries to contribute at four critical points, where significant improvement can be achieved by advanced human-computer interaction: (i) As the starting point of any 3D reconstruction process, the object of interest (OOI) that should be reconstructed needs to be annotated. For this task, novel pixel-accurate OOI annotation as an interactive process is presented, and an appropriate software solution is released. (ii) To improve the interactive annotation process, traditional interface devices, like mouse and keyboard, are supplemented with human sensory data to achieve closer user interaction. (iii) In practice, a major obstacle is the so far missing standard for file formats for annotation, which leads to numerous proprietary solutions. Therefore, a uniform standard file format is implemented and used for prototyping the first gaze-improved computer vision algorithms. As a sideline of this research, analogies between the close interaction of humans and computer vision systems and 3D perception are identified and evaluated. (iv) Finally, to reduce the processing time of the underlying algorithms used for 3D reconstruction, the ability of artificial neural networks to reconstruct 3D models of unknown OOIs is investigated. Summarizing, the gained improvements show that applicable image-based 3D reconstruction is within reach but nowadays only feasible by supporting human-computer interaction. Two software solutions, one for visual video analytics and one for spare part reconstruction are implemented. In the future, automated 3D reconstruction that produces functional 3D models can be reached only when algorithms become capable of acquiring semantic knowledge. Until then, the world knowledge provided to the 3D reconstruction pipeline by human computer interaction is indispensable.
157

Evolving Complex Neuro-Controllers with Interactively Constrained Neuro-Evolution

Rempis, Christian Wilhelm 17 October 2012 (has links)
In the context of evolutionary robotics and neurorobotics, artificial neural networks, used as controllers for animats, are examined to identify principles of neuro-control, network organization, the interaction between body and control, and other likewise properties. Before such an examination can take place, suitable neuro-controllers have to be identified. A promising and widely used technique to search for such networks are evolutionary algorithms specifically adapted for neural networks. These allow the search for neuro-controllers with various network topologies directly on physically grounded (simulated) animats. This neuro-evolution approach works well for small neuro-controllers and has lead to interesting results. However, due to the exponentially increasing search space with respect to the number of involved neurons, this approach does not scale well with larger networks. This scaling problem makes it difficult to find non-trivial, larger networks, that show interesting properties. In the context of this thesis, networks of this class are called mid-scale networks, having between 50 and 500 neurons. Searching for networks of this class involves very large search spaces, including all possible synaptic connections between the neurons, the bias terms of the neurons and (optionally) parameters of the neuron model, such as the transfer function, activation function or parameters of learning rules. In this domain, most evolutionary algorithms are not able to find suitable, non-trivial neuro-controllers in feasible time. To cope with this problem and to shift the frontier for evolvable network topologies a bit further, a novel evolutionary method has been developed in this thesis: the Interactively Constrained Neuro-Evolution method (ICONE). A way to approach the problem of increasing search spaces is the introduction of measures that reduce and restrict the search space back to a feasible domain. With ICONE, this restriction is realized with a unified, extensible and highly adaptable concept: Instead of evolving networks freely, networks are evolved within specifically designed constraint masks, that define mandatory properties of the evolving networks. These constraint masks are defined primarily using so called functional constraints, that actively modify a neural network to enforce the adherence of all required limitations and assumptions. Consequently, independently of the mutations taking place during evolution, the constraint masks repair and readjust the networks so that constraint violations are not able to evolve. Such functional constraints can be very specific and can enforce various network properties, such as symmetries, structure reuse, connectivity patterns, connectivity density heuristics, synaptic pathways, local processing assemblies, and much more. Constraint masks therefore describe a narrow, user defined subset of the parameter space -- based on domain knowledge and user experience -- that focuses the search on a smaller search space leading to a higher success rate for the evolution. Due to the involved domain knowledge, such evolutions are strongly biased towards specific classes of networks, because only networks within the defined search space can evolve. This, surely, can also be actively used to lead the evolution towards specific solution approaches, allowing the experimenter not only to search for any upcoming solution, but also to confirm assumptions about possible solutions. This makes it easier to investigate specific neuro-control principles, because the experimenter can systematically search for networks implementing the desired principles, simply by using suitable constraints to enforce them. Constraint masks in ICONE are built up by functional constraints working on so called neuro-modules. These modules are used to structure the networks, to define the scope for constraints and to simplify the reuse of (evolved) neural structures. The concept of functional, constrained neuro-modules allows a simple and flexible way to construct constraint masks and to inherit constraints when neuro-modules are reused or shared. A final cornerstone of the ICONE method is the interactive control of the evolution process, that allows the adaptation of the evolution parameters and the constraint masks to guide evolution towards promising domains and to counteract undesired developments. Due to the constraint masks, this interactive guidance is more effective than the adaptation of the evolution parameters alone, so that the identification of promising search space regions becomes easier. This thesis describes the ICONE method in detail and shows several applications of the method and the involved features. The examples demonstrate that the method can be used effectively for problems in the domain of mid-scale networks. Hereby, as effects of the constraint masks and the herewith reduced complexity of the networks, the results are -- despite their size -- often easy to comprehend, well analyzable and easy to reuse. Another benefit of constraint masks is the ability to deliberately search for very specific network configurations, which allows the effective and systematic exploration of distinct variations for an evolution experiment, simply by changing the constraint masks over the course of multiple evolution runs. The ICONE method therefore is a promising novel evolution method to tackle the problem of evolving mid-scale networks, pushing the frontier of evolvable networks a bit further. This allows for novel evolution experiments in the domain of neurorobotics and evolutionary robotics and may possibly lead to new insights into neuro-dynamical principles of animat control.
158

Information Processing in Neural Networks: Learning of Structural Connectivity and Dynamics of Functional Activation

Finger, Holger Ewald 16 March 2017 (has links)
Adaptability and flexibility are some of the most important human characteristics. Learning based on new experiences enables adaptation by changing the structural connectivity of the brain through plasticity mechanisms. But the human brain can also adapt to new tasks and situations in a matter of milliseconds by dynamic coordination of functional activation. To understand how this flexibility can be achieved in the computations performed by neural networks, we have to understand how the relatively fixed structural backbone interacts with the functional dynamics. In this thesis, I will analyze these interactions between the structural network connectivity and functional activations and their dynamic interactions on different levels of abstraction and spatial and temporal scales. One of the big questions in neuroscience is how functional interactions in the brain can adapt instantly to different tasks while the brain structure remains almost static. To improve our knowledge of the neural mechanisms involved, I will first analyze how dynamics in functional brain activations can be simulated based on the structural brain connectivity obtained with diffusion tensor imaging. In particular, I will show that a dynamic model of functional connectivity in the human cortex is more predictive of empirically measured functional connectivity than a stationary model of functional dynamics. More specifically, the simulations of a coupled oscillator model predict 54\% of the variance in the empirically measured EEG functional connectivity. Hypotheses of temporal coding have been proposed for the computational role of these dynamic oscillatory interactions on fast timescales. These oscillatory interactions play a role in the dynamic coordination between brain areas as well as between cortical columns or individual cells. Here I will extend neural network models, which learn unsupervised from statistics of natural stimuli, with phase variables that allow temporal coding in distributed representations. The analysis shows that synchronization of these phase variables provides a useful mechanism for binding of activated neurons, contextual coding, and figure ground segregation. Importantly, these results could also provide new insights for improvements of deep learning methods for machine learning tasks. The dynamic coordination in neural networks has also large influences on behavior and cognition. In a behavioral experiment, we analyzed multisensory integration between a native and an augmented sense. The participants were blindfolded and had to estimate their rotation angle based on their native vestibular input and the augmented information. Our results show that subjects alternate in the use between these modalities, indicating that subjects dynamically coordinate the information transfer of the involved brain regions. Dynamic coordination is also highly relevant for the consolidation and retrieval of associative memories. In this regard, I investigated the beneficial effects of sleep for memory consolidation in an electroencephalography (EEG) study. Importantly, the results demonstrate that sleep leads to reduced event-related theta and gamma power in the cortical EEG during the retrieval of associative memories, which could indicate the consolidation of information from hippocampal to neocortical networks. This highlights that cognitive flexibility comprises both dynamic organization on fast timescales and structural changes on slow timescales. Overall, the computational and empirical experiments demonstrate how the brain evolved to a system that can flexibly adapt to any situation in a matter of milliseconds. This flexibility in information processing is enabled by an effective interplay between the structure of the neural network, the functional activations, and the dynamic interactions on fast time scales.
159

Navigation Control & Path Planning for Autonomous Mobile Robots / Navigation Control and Path Planning for Autonomous Mobile Robots

Pütz, Sebastian Clemens Benedikt 11 February 2022 (has links)
Mobile robots need to move in the real world for the majority of tasks. Their control is often intertwined with the tasks they have to solve. Unforeseen events must have an adequate and prompt reaction, in order to solve the corresponding task satisfactorily. A robust system must be able to respond to a variety of events with specific solutions and strategies to keep the system running. Robot navigation control systems are essential for this. In this thesis we present a robot navigation control system that fulfills these requirements: Move Base Flex. Furthermore, the map representation used to model the environment is essential for path planning. Depending on the representation of the map, path planners can solve problems like simple 2D indoor navigation, but also complex rough terrain outdoor navigation with multiple levels and varying slopes, if the corresponding representation can model them accurately. With Move Base Flex, we present a middle layer navigation framework for navigation control, that is map independent at its core. Based on this, we present the Mesh Navigation Stack to master path planning in complex outdoor environments using a developed mesh map to model surfaces in 3D. Finally, to solve path planning in complex outdoor environments, we have developed and integrated the Continuous Vector Field Planner with the aforementioned solutions and evaluated it on five challenging and complex outdoor datasets in simulation and in the real-world. Beyond that, the corresponding developed software packages are open source available and have been released to easily reproduce the provided scientific results.
160

Improving drill-core hyperspectral mineral mapping using machine learning

Contreras Acosta, Isabel Cecilia 21 July 2022 (has links)
Considering the ever-growing global demand for raw materials and the complexity of the geological deposits that are still to be found, high-quality extensive mineralogical information is required. Mineral exploration remains a risk-prone process, with empirical approaches prevailing over data-driven strategy. Amongst the many ways to innovate, hyperspectral imaging sensors for drill-core mineral mapping are one of the disruptive technologies. This potential could be multiplied by implementing machine learning. This dissertation introduces a workflow that allows the use of supervised learning to map minerals by means of ancillary data commonly acquired during exploration campaigns (i.e., mineralogy, geochemistry and core photography). The fusion of hyperspectral with such ancillary data allows not only to upscale to complete boreholes information acquired locally, but also to enhance the spatial resolution of the mineral maps. Thus, the proposed approaches provide digitally archived objective maps that serve as vectors for exploration and support geologists in their decision making.:List of Figures xviii List of Tables xix List of Acronyms xxi 1 Introduction 1 1.1 Mineral resources and the need for innovation . . . . . . . . . . . . . 2 1.2 Spectroscopy and hyperspectral imaging . . . . . . . . . . . . . . . . 5 1.2.1 Imaging spectroscopy ....................... 6 1.2.2 Spectroscopy of minerals ..................... 8 1.2.3 Mineral mapping.......................... 12 1.2.4 Mineral mapping in exploration ................. 15 1.2.5 Drill-core mineral mapping.................... 16 1.3 Machine learning .............................. 19 1.3.1 Supervised learning for drill-core hyperspectral data . . . . . 20 1.4 Motivation and approach ......................... 22 2 Hyperspectral mineral mapping using supervised learning and mineralogical data 25 Preface ....................................... 25 Abstract....................................... 26 2.1 Introduction ................................. 27 2.2 Data acquisition............................... 30 2.2.1 Hyperspectral data......................... 30 2.2.2 High-resolution mineralogica ldata . . . . . . . . . . . . . . . 31 2.3 Proposed system architecture ....................... 33 2.3.1 Re-sampling and co-registration ................. 33 2.3.2 Classification ............................ 35 2.4 Experimental results ............................ 36 2.4.1 Data description .......................... 36 2.4.2 Experimental setup......................... 37 2.4.3 Quantitative and qualitative assessment . . . . . . . . . . . . . 37 2.5 Discussion.................................. 40 2.6 Conclusion.................................. 42 3 Geochemical and hyperspectral data integration 45 Preface ....................................... 45 Abstract....................................... 46 3.1 Introduction ................................. 47 3.2 Basis for the integration of geochemical and hyperspectral data . . . 50 3.3 Proposed approach ............................. 51 3.3.1 Geochemical data labeling..................... 51 3.3.2 Superpixel segmentation ..................... 53 3.3.3 Classification ............................ 53 3.4 Experimental results ............................ 54 3.4.1 Data description .......................... 54 3.4.2 Data acquisition........................... 55 3.4.3 Experimental setup......................... 55 3.4.4 Assessment of the geochemical data labeling . . . . . . . . . . 58 3.4.5 Quantitative and Qualitative Assessment . . . . . . . . . . . . 58 3.5 Discussion.................................. 61 3.6 Conclusion.................................. 63 4 Improved spatial resolution for mineral mapping 65 Preface ....................................... 65 Abstract....................................... 66 4.1 Introduction ................................. 67 4.2 Methods: Resolution Enhancement for Mineral Mapping . . . . . . . 69 4.2.1 Hyperspectral Resolution Enhancement . . . . . . . . . . . . . 69 4.2.2 Mineral Mapping.......................... 71 4.2.3 Supervised Classification ..................... 71 4.3 Case Study.................................. 72 4.3.1 Data Acquisition .......................... 72 4.3.2 Resolution Enhancement Application . . . . . . . . . . . . . . 74 4.3.3 Evaluation of the Resolution Enhancement . . . . . . . . . . . 75 4.4 Results .................................... 76 4.4.1 Mineral Mapping.......................... 76 4.4.2 Supervised Classification ..................... 77 4.4.3 Validation .............................. 80 4.5 Discussion.................................. 82 4.6 Conclusions ................................. 84 5 Bibliography 92

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