83 research outputs found

    Image-based Geolocalization by Ground-to-2.5D Map Matching

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    We study the image-based geolocalization problem, aiming to localize ground-view query images on cartographic maps. Current methods often utilize cross-view localization techniques to match ground-view query images with 2D maps. However, the performance of these methods is unsatisfactory due to significant cross-view appearance differences. In this paper, we lift cross-view matching to a 2.5D space, where heights of structures (e.g., trees and buildings) provide geometric information to guide the cross-view matching. We propose a new approach to learning representative embeddings from multi-modal data. Specifically, we establish a projection relationship between 2.5D space and 2D aerial-view space. The projection is further used to combine multi-modal features from the 2.5D and 2D maps using an effective pixel-to-point fusion method. By encoding crucial geometric cues, our method learns discriminative location embeddings for matching panoramic images and maps. Additionally, we construct the first large-scale ground-to-2.5D map geolocalization dataset to validate our method and facilitate future research. Both single-image based and route based localization experiments are conducted to test our method. Extensive experiments demonstrate that the proposed method achieves significantly higher localization accuracy and faster convergence than previous 2D map-based approaches

    A review of the role of sensors in mobile context-aware recommendation systems

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    Recommendation systems are specialized in offering suggestions about specific items of different types (e.g., books, movies, restaurants, and hotels) that could be interesting for the user. They have attracted considerable research attention due to their benefits and also their commercial interest. Particularly, in recent years, the concept of context-aware recommendation system has appeared to emphasize the importance of considering the context of the situations in which the user is involved in order to provide more accurate recommendations. The detection of the context requires the use of sensors of different types, which measure different context variables. Despite the relevant role played by sensors in the development of context-aware recommendation systems, sensors and recommendation approaches are two fields usually studied independently. In this paper, we provide a survey on the use of sensors for recommendation systems. Our contribution can be seen from a double perspective. On the one hand, we overview existing techniques used to detect context factors that could be relevant for recommendation. On the other hand, we illustrate the interest of sensors by considering different recommendation use cases and scenarios

    Deep Learning Applications in Industrial and Systems Engineering

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    Deep learning - the use of large neural networks to perform machine learning - has transformed the world. As the capabilities of deep models continue to grow, deep learning is becoming an increasingly valuable and practical tool for industrial engineering. With its wide applicability, deep learning can be turned to many industrial engineering tasks, including optimization, heuristic search, and functional approximation. In this dissertation, the major concepts and paradigms of deep learning are reviewed, and three industrial engineering projects applying these methods are described. The first applies a deep convolutional network to the task of absolute aerial geolocalization - the regression of real geographic coordinates from aerial photos - showing promising results. Next, continuing on this work, the features and characteristics of the deep aerial geolocalization model are further studied, with implications for future applications and methodological improvements. Lastly, a deep learning model is developed and applied to a difficult rare event problem of predicting failure times in oil and natural gas wells from process and site data. Practical details of applying deep learning to this sort of data are discussed, and methodological principles are proposed

    Unsupervised quantification of entity consistency between photos and text in real-world news

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    Das World Wide Web und die sozialen Medien übernehmen im heutigen Informationszeitalter eine wichtige Rolle für die Vermittlung von Nachrichten und Informationen. In der Regel werden verschiedene Modalitäten im Sinne der Informationskodierung wie beispielsweise Fotos und Text verwendet, um Nachrichten effektiver zu vermitteln oder Aufmerksamkeit zu erregen. Kommunikations- und Sprachwissenschaftler erforschen das komplexe Zusammenspiel zwischen Modalitäten seit Jahrzehnten und haben unter Anderem untersucht, wie durch die Kombination der Modalitäten zusätzliche Informationen oder eine neue Bedeutungsebene entstehen können. Die Anzahl gemeinsamer Konzepte oder Entitäten (beispielsweise Personen, Orte und Ereignisse) zwischen Fotos und Text stellen einen wichtigen Aspekt für die Bewertung der Gesamtaussage und Bedeutung eines multimodalen Artikels dar. Automatisierte Ansätze zur Quantifizierung von Bild-Text-Beziehungen können für zahlreiche Anwendungen eingesetzt werden. Sie ermöglichen beispielsweise eine effiziente Exploration von Nachrichten, erleichtern die semantische Suche von Multimedia-Inhalten in (Web)-Archiven oder unterstützen menschliche Analysten bei der Evaluierung der Glaubwürdigkeit von Nachrichten. Allerdings gibt es bislang nur wenige Ansätze, die sich mit der Quantifizierung von Beziehungen zwischen Fotos und Text beschäftigen. Diese Ansätze berücksichtigen jedoch nicht explizit die intermodalen Beziehungen von Entitäten, welche eine wichtige Rolle in Nachrichten darstellen, oder basieren auf überwachten multimodalen Deep-Learning-Techniken. Diese überwachten Lernverfahren können ausschließlich die intermodalen Beziehungen von Entitäten detektieren, die in annotierten Trainingsdaten enthalten sind. Um diese Forschungslücke zu schließen, wird in dieser Arbeit ein unüberwachter Ansatz zur Quantifizierung der intermodalen Konsistenz von Entitäten zwischen Fotos und Text in realen multimodalen Nachrichtenartikeln vorgestellt. Im ersten Teil dieser Arbeit werden neuartige Verfahren auf Basis von Deep Learning zur Extrahierung von Informationen aus Fotos vorgestellt, um Ereignisse (Events), Orte, Zeitangaben und Personen automatisch zu erkennen. Diese Verfahren bilden eine wichtige Voraussetzung, um die Beziehungen von Entitäten zwischen Bild und Text zu bewerten. Zunächst wird ein Ansatz zur Ereignisklassifizierung präsentiert, der neuartige Optimierungsfunktionen und Gewichtungsschemata nutzt um Ontologie-Informationen aus einer Wissensdatenbank in ein Deep-Learning-Verfahren zu integrieren. Das Training erfolgt anhand eines neu vorgestellten Datensatzes, der 570.540 Fotos und eine Ontologie mit 148 Ereignistypen enthält. Der Ansatz übertrifft die Ergebnisse von Referenzsystemen die keine strukturierten Ontologie-Informationen verwenden. Weiterhin wird ein DeepLearning-Ansatz zur Schätzung des Aufnahmeortes von Fotos vorgeschlagen, der Kontextinformationen über die Umgebung (Innen-, Stadt-, oder Naturaufnahme) und von Erdpartitionen unterschiedlicher Granularität verwendet. Die vorgeschlagene Lösung übertrifft die bisher besten Ergebnisse von aktuellen Forschungsarbeiten, obwohl diese deutlich mehr Fotos zum Training verwenden. Darüber hinaus stellen wir den ersten Datensatz zur Schätzung des Aufnahmejahres von Fotos vor, der mehr als eine Million Bilder aus den Jahren 1930 bis 1999 umfasst. Dieser Datensatz wird für das Training von zwei Deep-Learning-Ansätzen zur Schätzung des Aufnahmejahres verwendet, welche die Aufgabe als Klassifizierungs- und Regressionsproblem behandeln. Beide Ansätze erzielen sehr gute Ergebnisse und übertreffen Annotationen von menschlichen Probanden. Schließlich wird ein neuartiger Ansatz zur Identifizierung von Personen des öffentlichen Lebens und ihres gemeinsamen Auftretens in Nachrichtenfotos aus der digitalen Bibliothek Internet Archiv präsentiert. Der Ansatz ermöglicht es unstrukturierte Webdaten aus dem Internet Archiv mit Metadaten, beispielsweise zur semantischen Suche, zu erweitern. Experimentelle Ergebnisse haben die Effektivität des zugrundeliegenden Deep-Learning-Ansatzes zur Personenerkennung bestätigt. Im zweiten Teil dieser Arbeit wird ein unüberwachtes System zur Quantifizierung von BildText-Beziehungen in realen Nachrichten vorgestellt. Im Gegensatz zu bisherigen Verfahren liefert es automatisch neuartige Maße der intermodalen Konsistenz für verschiedene Entitätstypen (Personen, Orte und Ereignisse) sowie den Gesamtkontext. Das System ist nicht auf vordefinierte Datensätze angewiesen, und kann daher mit der Vielzahl und Diversität von Entitäten und Themen in Nachrichten umgehen. Zur Extrahierung von Entitäten aus dem Text werden geeignete Methoden der natürlichen Sprachverarbeitung eingesetzt. Examplarbilder für diese Entitäten werden automatisch aus dem Internet beschafft. Die vorgeschlagenen Methoden zur Informationsextraktion aus Fotos werden auf die Nachrichten- und heruntergeladenen Exemplarbilder angewendet, um die intermodale Konsistenz von Entitäten zu quantifizieren. Es werden zwei Aufgaben untersucht um die Qualität des vorgeschlagenen Ansatzes in realen Anwendungen zu bewerten. Experimentelle Ergebnisse für die Dokumentverifikation und die Beschaffung von Nachrichten mit geringer (potenzielle Fehlinformation) oder hoher multimodalen Konsistenz zeigen den Nutzen und das Potenzial des Ansatzes zur Unterstützung menschlicher Analysten bei der Untersuchung von Nachrichten.In today’s information age, the World Wide Web and social media are important sources for news and information. Different modalities (in the sense of information encoding) such as photos and text are typically used to communicate news more effectively or to attract attention. Communication scientists, linguists, and semioticians have studied the complex interplay between modalities for decades and investigated, e.g., how their combination can carry additional information or add a new level of meaning. The number of shared concepts or entities (e.g., persons, locations, and events) between photos and text is an important aspect to evaluate the overall message and meaning of an article. Computational models for the quantification of image-text relations can enable many applications. For example, they allow for more efficient exploration of news, facilitate semantic search and multimedia retrieval in large (web) archives, or assist human assessors in evaluating news for credibility. To date, only a few approaches have been suggested that quantify relations between photos and text. However, they either do not explicitly consider the cross-modal relations of entities – which are important in the news – or rely on supervised deep learning approaches that can only detect the cross-modal presence of entities covered in the labeled training data. To address this research gap, this thesis proposes an unsupervised approach that can quantify entity consistency between photos and text in multimodal real-world news articles. The first part of this thesis presents novel approaches based on deep learning for information extraction from photos to recognize events, locations, dates, and persons. These approaches are an important prerequisite to measure the cross-modal presence of entities in text and photos. First, an ontology-driven event classification approach that leverages new loss functions and weighting schemes is presented. It is trained on a novel dataset of 570,540 photos and an ontology with 148 event types. The proposed system outperforms approaches that do not use structured ontology information. Second, a novel deep learning approach for geolocation estimation is proposed that uses additional contextual information on the environmental setting (indoor, urban, natural) and from earth partitions of different granularity. The proposed solution outperforms state-of-the-art approaches, which are trained with significantly more photos. Third, we introduce the first large-scale dataset for date estimation with more than one million photos taken between 1930 and 1999, along with two deep learning approaches that treat date estimation as a classification and regression problem. Both approaches achieve very good results that are superior to human annotations. Finally, a novel approach is presented that identifies public persons and their co-occurrences in news photos extracted from the Internet Archive, which collects time-versioned snapshots of web pages that are rarely enriched with metadata relevant to multimedia retrieval. Experimental results confirm the effectiveness of the deep learning approach for person identification. The second part of this thesis introduces an unsupervised approach capable of quantifying image-text relations in real-world news. Unlike related work, the proposed solution automatically provides novel measures of cross-modal consistency for different entity types (persons, locations, and events) as well as the overall context. The approach does not rely on any predefined datasets to cope with the large amount and diversity of entities and topics covered in the news. State-of-the-art tools for natural language processing are applied to extract named entities from the text. Example photos for these entities are automatically crawled from the Web. The proposed methods for information extraction from photos are applied to both news images and example photos to quantify the cross-modal consistency of entities. Two tasks are introduced to assess the quality of the proposed approach in real-world applications. Experimental results for document verification and retrieval of news with either low (potential misinformation) or high cross-modal similarities demonstrate the feasibility of the approach and its potential to support human assessors to study news

    Toward Global Localization of Unmanned Aircraft Systems using Overhead Image Registration with Deep Learning Convolutional Neural Networks

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    Global localization, in which an unmanned aircraft system (UAS) estimates its unknown current location without access to its take-off location or other locational data from its flight path, is a challenging problem. This research brings together aspects from the remote sensing, geoinformatics, and machine learning disciplines by framing the global localization problem as a geospatial image registration problem in which overhead aerial and satellite imagery serve as a proxy for UAS imagery. A literature review is conducted covering the use of deep learning convolutional neural networks (DLCNN) with global localization and other related geospatial imagery applications. Differences between geospatial imagery taken from the overhead perspective and terrestrial imagery are discussed, as well as difficulties in using geospatial overhead imagery for image registration due to a lack of suitable machine learning datasets. Geospatial analysis is conducted to identify suitable areas for future UAS imagery collection. One of these areas, Jerusalem northeast (JNE) is selected as the area of interest (AOI) for this research. Multi-modal, multi-temporal, and multi-resolution geospatial overhead imagery is aggregated from a variety of publicly available sources and processed to create a controlled image dataset called Jerusalem northeast rural controlled imagery (JNE RCI). JNE RCI is tested with handcrafted feature-based methods SURF and SIFT and a non-handcrafted feature-based pre-trained fine-tuned VGG-16 DLCNN on coarse-grained image registration. Both handcrafted and non-handcrafted feature based methods had difficulty with the coarse-grained registration process. The format of JNE RCI is determined to be unsuitable for the coarse-grained registration process with DLCNNs and the process to create a new supervised machine learning dataset, Jerusalem northeast machine learning (JNE ML) is covered in detail. A multi-resolution grid based approach is used, where each grid cell ID is treated as the supervised training label for that respective resolution. Pre-trained fine-tuned VGG-16 DLCNNs, two custom architecture two-channel DLCNNs, and a custom chain DLCNN are trained on JNE ML for each spatial resolution of subimages in the dataset. All DLCNNs used could more accurately coarsely register the JNE ML subimages compared to the pre-trained fine-tuned VGG-16 DLCNN on JNE RCI. This shows the process for creating JNE ML is valid and is suitable for using machine learning with the coarse-grained registration problem. All custom architecture two-channel DLCNNs and the custom chain DLCNN were able to more accurately coarsely register the JNE ML subimages compared to the fine-tuned pre-trained VGG-16 approach. Both the two-channel custom DLCNNs and the chain DLCNN were able to generalize well to new imagery that these networks had not previously trained on. Through the contributions of this research, a foundation is laid for future work to be conducted on the UAS global localization problem within the rural forested JNE AOI
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