Zugl.: Berlin, Freie Universiẗat, Diss., 2006.

Teilw. zugl.: Europa Universität Viadrina, Frankfurt (Oder), Diss., 2006 u.d.T.: Dyroff, Stefan: Erinnerungskultur im Nordosten der Provinz Posen (Wojewodschaft Poznań) in den Jahren 1871 bis 1939

Zugl.: Frankfurt (Oder), Univ., Diss., 2006 u.d.T.: Dyroff, Stefan: Erinnerungskultur im Nordosten der Provinz Posen (Wojewodschaft Poznan) in der Jahren 1871 bis 1939

No description available.

Zugl.: Frankfurt/Oder, Universiẗat, Diss., 2003.

Pendant presque un demi-siècle, entre la proclamation de 1871 et la défaite de 1918, l’Empire allemand a soumis trois départements français annexés et l’ancien Grand- Duché de Pologne ou Poznanie, déjà sous domination prussienne, à de vigoureuses campagnes de germanisation dont le principal vecteur a été l’école allemande. De cette empreinte germanique témoignent des manuels scolaires, des écrits fictionnels ou mémoriels peu connus de la recherche et qui permettent d’apprécier l’incidence du phénomène à court et à long terme dans les deux provinces concernées. Un siècle après, les témoignages rassemblés autour de cet objet éveillent l’intérêt du culturaliste. En quoi le concept de colonisation s’applique-t-il à la germanisation par l’école? Les politiques scolaires appliquées à l’Ouest et à l’Est sont-elles similaires, sont-elles comparables à celles pratiquées outre-mer ? Quelle a été l’emprise de l’école prussienne sur une jeunesse appelée à connaître, quelquefois sur plusieurs générations, un déchirement entre son appartenance nationale et son identité culturelle ? Peut-on un siècle plus tard assimiler ce phénomène à un syndrome post colonial ? / Over a period of nearly five hundred years , i.e. between the proclamation of the German Empire in 1871 and the defeat in 1918, 3 French annexed départements and the Grand Duchy of Poland (also called Posen) - itself under Prussian domination-, have been submitted to hard campaigns of germanization. School was the main vector. In addition to school books, a number of fictional writings or written memories helped to mark that German print in the minds, but researchers know little about this literature though it helps to appreciate the importance of the phenomenon in the short but also in the long run when a comparison is made between the two provinces concerned. A century later, the culturalists' interest is aroused by the testimonies gathered on this subject in its historical context. This work aims at presenting in what way the concept of colonisation can be applied to germanization, particularly regarding the germanization of the school. We will also examine whether the school politics applied in the west and the east of Europe are similar and if they can be compared to those applied abroad. What was the outcome for the youth in the populations concerned, for those who attended the Prussian educational system facing the possible risk of being torn apart between a sense of national allegiance and their cultural identity? Can this feeling be assimilated to a post colonial syndrome?

Zugl.: Kassel, Universiẗat, Diss., 2008.

Am Beispiel der Kunsthistorischen Institute Breslau und Posen sowie der dort tätigen Kunsthistoriker und Kunsthistorikerinnen wird dargelegt, wie sich in der Zeit des Nationalsozialismus die Disziplin Kunstgeschichte an der sog. Ostforschung beteiligte. Die "Ostforschung" zielte nicht auf eine Erforschung von Kunst und Kultur der osteuropäischen Nachbarländer ab, sondern auf die Ermittlung des "deutschen" Anteils an deren Herausbildung. Mit Breslau und seinem Direktor Dagobert Frey stehen einerseits ein Institut und ein Protagonist an der Ostgrenze des Deutschen Reiches und mit Posen andererseits ein im besetzten Polen an der Reichsuniversität gegründetes Institut und sein Leiter Otto Kletzl im Fokus. Der Schwerpunkt wird auf deren Forschungen zum Nachbarland Polen gelegt. Die Autorin zeigt auf, wie politische Prämissen Eingang in die Lehre und in die Publikationen fanden und wie diese Positionen durch Vorträge und Ausstellungsmitarbeit auch im außeruniversitären Bereich vermittelt und verbreitet wurden. Die Direktoren beider Institute waren zudem in weiteren außeruniversitären Forschungsprojekten, Vereinen sowie Institutionen der Ostforschung aktiv. Sowohl Dagobert Frey (Breslau) als auch Otto Kletzl (Posen) beteiligten sich zudem für eine begrenzte Zeit als Kunstgutachter am Kunstraub im besetzten Polen. Neben diesen beiden Hauptprotagonisten werden die Karriereverläufe von Nachwuchswissenschaftlern und Nachwuchswissenschaftlerinnen dargelegt, eröffnete der Krieg doch für eine begrenzte Zeit auch Frauen die Möglichkeit, in akademische Positionen zu gelangen. Die Arbeit kombiniert auf der Basis einer umfassenden Quellenrecherche institutionengeschichtliche, biographische und handlungstheoretische Ansätze, um die Handlungsspielräume im Spannungsfeld von Wissenschaft und Politik herauszuarbeiten. Die Autorin kommt zu dem Ergebnis, dass sich die untersuchten Kunsthistoriker an der Legitimierung und Unterstützung der deutschen Okkupationspolitik in Osteuropa beteiligten. / Focussing the institutes of art history in Breslau und Posen as well as male and female arthistorians working there the author shows how the discipline arthistory participated in the so-called Ostforschung (Eastern research) in the time of nationalsocialism. "Eastern research" was not interested in the research of art and culture of the Easteuropean neighbourcontries, but in the "German" role in their development. Two places, persons and institutes are the center (focus): Breslau and its director Dagobert Frey and his institute, a protagonist from the Eastern border of the German Reich on the one hand and Otto Kletzl - leader of an institute in Posen at the so-called ReichsuniversitŠt (Reichs-University) on the other hand. The main focus lies on their research concerning Poland. The author shows how political topics found their way in the teaching: in lectures as well as in the publications. She also makes clear how their positions were spread in the field beyond universiy by lectures and their participation in exhibitions. Both directors have further been very active in non-university research projects, associations and institutes of the Eastern research. Dagobert Frey (Breslau) and also Otto Kletzl (Posen) participated for a certain time as experts in the art robbery in occupied Poland. Next to these main protagonists the career of young researchers, men and women, are presented. For a short time the war opens women the opportunity to get into academic positions. Based on a broad archival research the author combines institutional, biographical and action theory approaches to show the scope of activities in the tension zone between science and politics. She comes to the result that the art historians participated in the legitimization and support of the German occupation politics in Eastern Europe.

This work aims at providing a novel camera motion estimation pipeline from large collections of unordered omnidirectional images. In oder to keep the pipeline as general and flexible as possible, cameras are modelled as unit spheres, allowing to incorporate any central camera type. For each camera an unprojection lookup is generated from intrinsics, which is called P2S-map (Pixel-to-Sphere-map), mapping pixels to their corresponding positions on the unit sphere. Consequently the camera geometry becomes independent of the underlying projection model. The pipeline also generates P2S-maps from world map projections with less distortion effects as they are known from cartography. Using P2S-maps from camera calibration and world map projection allows to convert omnidirectional camera images to an appropriate world map projection in oder to apply standard feature extraction and matching algorithms for data association. The proposed estimation pipeline combines the flexibility of SfM (Structure from Motion) - which handles unordered image collections - with the efficiency of PGO (Pose Graph Optimization), which is used as back-end in graph-based Visual SLAM (Simultaneous Localization and Mapping) approaches to optimize camera poses from large image sequences. SfM uses BA (Bundle Adjustment) to jointly optimize camera poses (motion) and 3d feature locations (structure), which becomes computationally expensive for large-scale scenarios. On the contrary PGO solves for camera poses (motion) from measured transformations between cameras, maintaining optimization managable. The proposed estimation algorithm combines both worlds. It obtains up-to-scale transformations between image pairs using two-view constraints, which are jointly scaled using trifocal constraints. A pose graph is generated from scaled two-view transformations and solved by PGO to obtain camera motion efficiently even for large image collections. Obtained results can be used as input data to provide initial pose estimates for further 3d reconstruction purposes e.g. to build a sparse structure from feature correspondences in an SfM or SLAM framework with further refinement via BA. The pipeline also incorporates fixed extrinsic constraints from multi-camera setups as well as depth information provided by RGBD sensors. The entire camera motion estimation pipeline does not need to generate a sparse 3d structure of the captured environment and thus is called SCME (Structureless Camera Motion Estimation).:1 Introduction 1.1 Motivation 1.1.1 Increasing Interest of Image-Based 3D Reconstruction 1.1.2 Underground Environments as Challenging Scenario 1.1.3 Improved Mobile Camera Systems for Full Omnidirectional Imaging 1.2 Issues 1.2.1 Directional versus Omnidirectional Image Acquisition 1.2.2 Structure from Motion versus Visual Simultaneous Localization and Mapping 1.3 Contribution 1.4 Structure of this Work 2 Related Work 2.1 Visual Simultaneous Localization and Mapping 2.1.1 Visual Odometry 2.1.2 Pose Graph Optimization 2.2 Structure from Motion 2.2.1 Bundle Adjustment 2.2.2 Structureless Bundle Adjustment 2.3 Corresponding Issues 2.4 Proposed Reconstruction Pipeline 3 Cameras and Pixel-to-Sphere Mappings with P2S-Maps 3.1 Types 3.2 Models 3.2.1 Unified Camera Model 3.2.2 Polynomal Camera Model 3.2.3 Spherical Camera Model 3.3 P2S-Maps - Mapping onto Unit Sphere via Lookup Table 3.3.1 Lookup Table as Color Image 3.3.2 Lookup Interpolation 3.3.3 Depth Data Conversion 4 Calibration 4.1 Overview of Proposed Calibration Pipeline 4.2 Target Detection 4.3 Intrinsic Calibration 4.3.1 Selected Examples 4.4 Extrinsic Calibration 4.4.1 3D-2D Pose Estimation 4.4.2 2D-2D Pose Estimation 4.4.3 Pose Optimization 4.4.4 Uncertainty Estimation 4.4.5 PoseGraph Representation 4.4.6 Bundle Adjustment 4.4.7 Selected Examples 5 Full Omnidirectional Image Projections 5.1 Panoramic Image Stitching 5.2 World Map Projections 5.3 World Map Projection Generator for P2S-Maps 5.4 Conversion between Projections based on P2S-Maps 5.4.1 Proposed Workflow 5.4.2 Data Storage Format 5.4.3 Real World Example 6 Relations between Two Camera Spheres 6.1 Forward and Backward Projection 6.2 Triangulation 6.2.1 Linear Least Squares Method 6.2.2 Alternative Midpoint Method 6.3 Epipolar Geometry 6.4 Transformation Recovery from Essential Matrix 6.4.1 Cheirality 6.4.2 Standard Procedure 6.4.3 Simplified Procedure 6.4.4 Improved Procedure 6.5 Two-View Estimation 6.5.1 Evaluation Strategy 6.5.2 Error Metric 6.5.3 Evaluation of Estimation Algorithms 6.5.4 Concluding Remarks 6.6 Two-View Optimization 6.6.1 Epipolar-Based Error Distances 6.6.2 Projection-Based Error Distances 6.6.3 Comparison between Error Distances 6.7 Two-View Translation Scaling 6.7.1 Linear Least Squares Estimation 6.7.2 Non-Linear Least Squares Optimization 6.7.3 Comparison between Initial and Optimized Scaling Factor 6.8 Homography to Identify Degeneracies 6.8.1 Homography for Spherical Cameras 6.8.2 Homography Estimation 6.8.3 Homography Optimization 6.8.4 Homography and Pure Rotation 6.8.5 Homography in Epipolar Geometry 7 Relations between Three Camera Spheres 7.1 Three View Geometry 7.2 Crossing Epipolar Planes Geometry 7.3 Trifocal Geometry 7.4 Relation between Trifocal, Three-View and Crossing Epipolar Planes 7.5 Translation Ratio between Up-To-Scale Two-View Transformations 7.5.1 Structureless Determination Approaches 7.5.2 Structure-Based Determination Approaches 7.5.3 Comparison between Proposed Approaches 8 Pose Graphs 8.1 Optimization Principle 8.2 Solvers 8.2.1 Additional Graph Solvers 8.2.2 False Loop Closure Detection 8.3 Pose Graph Generation 8.3.1 Generation of Synthetic Pose Graph Data 8.3.2 Optimization of Synthetic Pose Graph Data 9 Structureless Camera Motion Estimation 9.1 SCME Pipeline 9.2 Determination of Two-View Translation Scale Factors 9.3 Integration of Depth Data 9.4 Integration of Extrinsic Camera Constraints 10 Camera Motion Estimation Results 10.1 Directional Camera Images 10.2 Omnidirectional Camera Images 11 Conclusion 11.1 Summary 11.2 Outlook and Future Work Appendices A.1 Additional Extrinsic Calibration Results A.2 Linear Least Squares Scaling A.3 Proof Rank Deficiency A.4 Alternative Derivation Midpoint Method A.5 Simplification of Depth Calculation A.6 Relation between Epipolar and Circumferential Constraint A.7 Covariance Estimation A.8 Uncertainty Estimation from Epipolar Geometry A.9 Two-View Scaling Factor Estimation: Uncertainty Estimation A.10 Two-View Scaling Factor Optimization: Uncertainty Estimation A.11 Depth from Adjoining Two-View Geometries A.12 Alternative Three-View Derivation A.12.1 Second Derivation Approach A.12.2 Third Derivation Approach A.13 Relation between Trifocal Geometry and Alternative Midpoint Method A.14 Additional Pose Graph Generation Examples A.15 Pose Graph Solver Settings A.16 Additional Pose Graph Optimization Examples Bibliography