129 research outputs found

    Geodetic infrastructure of Serbia

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    Geodetic reference systems and their realization at the territory of Serbia have been created and maintained since the end of 19th century. Until mid-80s a series of reference geodetic networks were established: trigonometric networks in four orders, two levelling networks of high accuracybut also a series of gravimetric networks. In the following period of 20 years, there were not any organized worksaiming to maintenance of existing networks and creating new ones. In 1996, works started again on developing a new geodetic infrastructure in the form of realizing: a passive geodetic network, a network of permanent stations (AGROS – the active geodetic reference network of Serbia) as well as basic gravimetric networks. In this paperwork, a short review of works aiming to establish and use said networks is given but also a series of suggestions for a future development of geodetic infrastructure of Serbia

    Applications of POD studies and robust design to electromagnetic NDE

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    Numerical techniques, such as finite element methods (FEM), have been widely used in predicting defect signatures in nondestructive evaluation (NDE). The test conditions in the numerical models are deterministic in nature. However, signals generated by identical flaws are usually different under practical testing conditions. This affects the reliability of NDE methods. A considerable amount of attention has been focused towards quantifying the reliability of a variety of NDE methods, which has led to development of models for evaluating probability of detection (POD). Sources of variabilities that influence POD in NDE systems vary due to different testing modalities. POD models not only help in improving accuracy in flaw detection but also help in optimizing operational parameters. The Taguchi method, also called robust design in literature, is a well-established technique for optimizing the design parameters in an experiment.;This dissertation presents a comprehensive POD model for quasi-static electromagnetic NDE. Applications of Taguchi methods as well as POD models in magnetic flux leakage (MFL) and magneto-optic/eddy current imaging inspections are investigated in this research

    Verbesserte Dokumentation des kulturellen Erbes mithilfe digitaler Photogrammetrie mit sichtbaren und thermischen Bildern von unbemannten Luftfahrzeugen (UAV)

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    There is always need for reliable and accurate data for documentation of cultural heritage including archaeological areas. The development in 3D data acquisition has let some technologies use for getting a complete documentation. Close range photogrammetry and terrestrial laser scanning are among the most common used techniques which help to get 3D data acquisition, with high level of detail, accuracy and effective results. However, these techniques are not always the most suitable ones for large archaeological areas, yet aerial images may help to provide a general overview of the area which is fundamental for interpretation and documentation of archaeological sites. Because of the limitations in aerial photogrammetry, UAVs (Unmanned Aerial Vehicles) has become an optimal solution for archaeological areas documentation with its potentials in the context of costs and abilities. To cover large areas at different altitudes, to be able to fly at different altitudes, under different weather conditions, to acquire image with high resolution are among the main advantages of this technology which make it usable and preferable for archaeological documentation. Since UAVs have been rapidly improving in sophistication and reliability, its possibilities aid in archaeological research have recently generated much interest, particularly for documenting sites, monuments and excavations. In this case study several aerial surveys will be conducted with a UAV mounted thermal camera on an archaeological area. After acquiring aerial images, they will be processed for producing both color and thermal-imagery in related software. Next step will be the alignment of the images in order to build an accurate and georeferenced 3D and mesh model of surveyed area. Then colored and thermal orthophoto mosaics as well as digital surface model (DSM) will be obtained for the documentation. The datasets of thermal images and color images will be collected and compared in order to detect archaeological remains on and under the ground.Es besteht immer Bedarf an zuverlässigen und genauen Daten für die Dokumentation des kulturellen Erbes, einschließlich archäologischer Gebiete. Die technischen Entwicklungen in der 3D-Datenerfassung haben erst die vollständige Dokumentation ermöglicht. Nahbereichsphotogrammetrie und terrestrisches Laserscanning gehören zu den am häufigsten verwendeten Techniken, die 3D-Datenerfassung mit hohem Detaillierungsgrad, Genauigkeit und effektive Ergebnissen ermöglichen. Diese Techniken sind jedoch nicht immer die am besten geeigneten für große archäologische Gebiete, dennoch können Luftbilder helfen, einen allgemeinen Überblick über das Gebiet zu geben, was für die Interpretation und Dokumentation archäologischer Stätten von grundlegender Bedeutung ist. Aufgrund der Einschränkungen in der Luftbildvermessung sind UAVs (Unmanned Aerial Vehicles) zu einer optimalen Lösung für die archäologische Geländedokumentation mit ihren Potenzialen im Kontext von Kosten und Fähigkeiten geworden. Hauptvorteile dieser Technologie sind u.a. große Gebiete in verschiedenen Höhen abzudecken und unter verschiedenen Wetterbedingungen fliegen zu können, Bilder mit hoher Auflösung aufzunehmen, die dann auch für die archäologische Dokumentation nutzbar und damit auch anderen Verfahren vorzuziehen sind. Da sich die UAVs in Bezug auf Entwicklungsgrad und Zuverlässigkeit rasant verbessert haben, haben ihre Möglichkeiten zur Unterstützung der archäologischen Forschung in jüngster Zeit großes Interesse geweckt, insbesondere bei der Dokumentation von Stätten, Denkmälern und Ausgrabungen. In dieser Fallstudie werden mehrere Kampagnen von Luftaufnahmen mit einer UAV-Wärmebildkamera auf einem archäologischen Gebiet durchgeführt. Nach der Bildaufufnahme die Farb- und Wärmebilder in einer entsprechenden Software verarbeitet. Der nächste Schritt wird die Verknüpfung der Bilder sein, um ein genaues und georeferenziertes 3D- und Netzmodell des vermessenden Bereichs zu erstellen. Anschließend werden farbige und thermische Orthophoto-Mosaike sowie digitale Oberflächenmodelle (DSM) für die Dokumentation abgeleitet. Die Datensätze von Wärme- und Farbbildern werden gesammelt und verglichen, um archäologische Überreste auf und unter dem Boden zu erkennen

    Proceedings of the ECCOMAS Thematic Conference on Multibody Dynamics 2015

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    This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: ● Formulations and Numerical Methods ● Efficient Methods and Real-Time Applications ● Flexible Multibody Dynamics ● Contact Dynamics and Constraints ● Multiphysics and Coupled Problems ● Control and Optimization ● Software Development and Computer Technology ● Aerospace and Maritime Applications ● Biomechanics ● Railroad Vehicle Dynamics ● Road Vehicle Dynamics ● Robotics ● Benchmark ProblemsPostprint (published version

    Assessment of the CORONA series of satellite imagery for landscape archaeology: a case study from the Orontes valley, Syria

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    In 1995, a large database of satellite imagery with worldwide coverage taken from 1960 until 1972 was declassified. The main advantages of this imagery known as CORONA that made it attractive for archaeology were its moderate cost and its historical value. The main disadvantages were its unknown quality, format, geometry and the limited base of known applications. This thesis has sought to explore the properties and potential of CORONA imagery and thus enhance its value for applications in landscape archaeology. In order to ground these investigations in a real dataset, the properties and characteristics of CORONA imagery were explored through the case study of a landscape archaeology project working in the Orontes Valley, Syria. Present-day high-resolution IKONOS imagery was integrated within the study and assessed alongside CORONA imagery. The combination of these two image datasets was shown to provide a powerful set of tools for investigating past archaeological landscape in the Middle East. The imagery was assessed qualitatively through photointerpretation for its ability to detect archaeological remains, and quantitatively through the extraction of height information after the creation of stereomodels. The imagery was also assessed spectrally through fieldwork and spectroradiometric analysis, and for its Multiple View Angle (MVA) capability through visual and statistical analysis. Landscape archaeology requires a variety of data to be gathered from a large area, in an effective and inexpensive way. This study demonstrates an effective methodology for the deployment of CORONA and IKONOS imagery and raises a number of technical points of which the archaeological researcher community need to be aware of. Simultaneously, it identified certain limitations of the data and suggested solutions for the more effective exploitation of the strengths of CORONA imagery

    EUSPEN : proceedings of the 3rd international conference, May 26-30, 2002, Eindhoven, The Netherlands

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