TY - GEN A1 - Delikostidis, Ioannis A1 - Engel, Juri A1 - Retsios, Bas A1 - Elzakker, Corné P.J.M. van A1 - Kraak, Menno-Jan A1 - Döllner, Jürgen Roland Friedrich T1 - Increasing the usability of pedestrian navigation interfaces by means of landmark visibility analysis T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - Communicating location-specific information to pedestrians is a challenging task which can be aided by user-friendly digital technologies. In this paper, landmark visibility analysis, as a means for developing more usable pedestrian navigation systems, is discussed. Using an algorithmic framework for image-based 3D analysis, this method integrates a 3D city model with identified landmarks and produces raster visibility layers for each one. This output enables an Android phone prototype application to indicate the visibility of landmarks from the user's actual position. Tested in the field, the method achieves sufficient accuracy for the context of use and improves navigation efficiency and effectiveness. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 599 KW - pedestrian navigation KW - landmark visibility KW - user-centred design KW - usability testing Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415500 SN - 1866-8372 IS - 599 SP - 523 EP - 537 ER - TY - BOOK A1 - Döllner, Jürgen Roland Friedrich A1 - Kirsch, Florian A1 - Nienhaus, Marc T1 - Visualizing Design and Spatial Assembly of Interactive CSG N2 - For interactive construction of CSG models understanding the layout of a model is essential for its efficient manipulation. To understand position and orientation of aggregated components of a CSG model, we need to realize its visible and occluded parts as a whole. Hence, transparency and enhanced outlines are key techniques to assist comprehension. We present a novel real-time rendering technique for visualizing design and spatial assembly of CSG models. As enabling technology we combine an image-space CSG rendering algorithm with blueprint rendering. Blueprint rendering applies depth peeling for extracting layers of ordered depth from polygonal models and then composes them in sorted order facilitating a clear insight of the models. We develop a solution for implementing depth peeling for CSG models considering their depth complexity. Capturing surface colors of each layer and later combining the results allows for generating order-independent transparency as one major rendering technique for CSG models. We further define visually important edges for CSG models and integrate an image-space edgeenhancement technique for detecting them in each layer. In this way, we extract visually important edges that are directly and not directly visible to outline a model’s layout. Combining edges with transparency rendering, finally, generates edge-enhanced depictions of image-based CSG models and allows us to realize their complex, spatial assembly. T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 07 Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-33771 SN - 978-3-937786-56-2 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Isailović, Dušan A1 - Stojanovic, Vladeta A1 - Trapp, Matthias A1 - Richter, Rico A1 - Hajdin, Rade A1 - Döllner, Jürgen Roland Friedrich T1 - Bridge damage BT - detection, IFC-based semantic enrichment and visualization JF - Automation in construction : an international research journal N2 - Building Information Modeling (BIM) representations of bridges enriched by inspection data will add tremendous value to future Bridge Management Systems (BMSs). This paper presents an approach for point cloud-based detection of spalling damage, as well as integrating damage components into a BIM via semantic enrichment of an as-built Industry Foundation Classes (IFC) model. An approach for generating the as-built BIM, geometric reconstruction of detected damage point clusters and semantic-enrichment of the corresponding IFC model is presented. Multiview-classification is used and evaluated for the detection of spalling damage features. The semantic enrichment of as-built IFC models is based on injecting classified and reconstructed damage clusters back into the as-built IFC, thus generating an accurate as-is IFC model compliant to the BMS inspection requirements. KW - damage detection KW - building information modeling KW - 3D point clouds KW - multiview classification KW - bridge management systems Y1 - 2020 U6 - https://doi.org/10.1016/j.autcon.2020.103088 SN - 0926-5805 SN - 1872-7891 VL - 112 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Scheibel, Willy A1 - Trapp, Matthias A1 - Limberger, Daniel A1 - Döllner, Jürgen Roland Friedrich T1 - A taxonomy of treemap visualization techniques T2 - Postprints der Universität Potsdam : Reihe der Digital Engineering Fakultät N2 - A treemap is a visualization that has been specifically designed to facilitate the exploration of tree-structured data and, more general, hierarchically structured data. The family of visualization techniques that use a visual metaphor for parent-child relationships based “on the property of containment” (Johnson, 1993) is commonly referred to as treemaps. However, as the number of variations of treemaps grows, it becomes increasingly important to distinguish clearly between techniques and their specific characteristics. This paper proposes to discern between Space-filling Treemap TS, Containment Treemap TC, Implicit Edge Representation Tree TIE, and Mapped Tree TMT for classification of hierarchy visualization techniques and highlights their respective properties. This taxonomy is created as a hyponymy, i.e., its classes have an is-a relationship to one another: TS TC TIE TMT. With this proposal, we intend to stimulate a discussion on a more unambiguous classification of treemaps and, furthermore, broaden what is understood by the concept of treemap itself. T3 - Zweitveröffentlichungen der Universität Potsdam : Reihe der Digital Engineering Fakultät - 8 KW - treemaps KW - taxonomy Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-524693 IS - 8 ER - TY - JOUR A1 - Discher, Sören A1 - Richter, Rico A1 - Döllner, Jürgen Roland Friedrich T1 - Concepts and techniques for web-based visualization and processing of massive 3D point clouds with semantics JF - Graphical Models N2 - 3D point cloud technology facilitates the automated and highly detailed acquisition of real-world environments such as assets, sites, and countries. We present a web-based system for the interactive exploration and inspection of arbitrary large 3D point clouds. Our approach is able to render 3D point clouds with billions of points using spatial data structures and level-of-detail representations. Point-based rendering techniques and post-processing effects are provided to enable task-specific and data-specific filtering, e.g., based on semantics. A set of interaction techniques allows users to collaboratively work with the data (e.g., measuring distances and annotating). Additional value is provided by the system’s ability to display additional, context-providing geodata alongside 3D point clouds and to integrate processing and analysis operations. We have evaluated the presented techniques and in case studies and with different data sets from aerial, mobile, and terrestrial acquisition with up to 120 billion points to show their practicality and feasibility. KW - 3D Point clouds KW - Web-based rendering KW - Point-based rendering KW - Processing strategies Y1 - 2019 U6 - https://doi.org/10.1016/j.gmod.2019.101036 SN - 1524-0703 SN - 1524-0711 VL - 104 PB - Elsevier CY - San Diego ER - TY - GEN A1 - Discher, Sören A1 - Richter, Rico A1 - Döllner, Jürgen Roland Friedrich ED - Spencer, SN T1 - A scalable webGL-based approach for visualizing massive 3D point clouds using semantics-dependent rendering techniques T2 - Web3D 2018: The 23rd International ACM Conference on 3D Web Technology N2 - 3D point cloud technology facilitates the automated and highly detailed digital acquisition of real-world environments such as assets, sites, cities, and countries; the acquired 3D point clouds represent an essential category of geodata used in a variety of geoinformation applications and systems. In this paper, we present a web-based system for the interactive and collaborative exploration and inspection of arbitrary large 3D point clouds. Our approach is based on standard WebGL on the client side and is able to render 3D point clouds with billions of points. It uses spatial data structures and level-of-detail representations to manage the 3D point cloud data and to deploy out-of-core and web-based rendering concepts. By providing functionality for both, thin-client and thick-client applications, the system scales for client devices that are vastly different in computing capabilities. Different 3D point-based rendering techniques and post-processing effects are provided to enable task-specific and data-specific filtering and highlighting, e.g., based on per-point surface categories or temporal information. A set of interaction techniques allows users to collaboratively work with the data, e.g., by measuring distances and areas, by annotating, or by selecting and extracting data subsets. Additional value is provided by the system's ability to display additional, context-providing geodata alongside 3D point clouds and to integrate task-specific processing and analysis operations. We have evaluated the presented techniques and the prototype system with different data sets from aerial, mobile, and terrestrial acquisition campaigns with up to 120 billion points to show their practicality and feasibility. KW - 3D Point Clouds KW - web-based rendering KW - point-based rendering Y1 - 2018 SN - 978-1-4503-5800-2 U6 - https://doi.org/10.1145/3208806.3208816 SP - 1 EP - 9 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Discher, Sören A1 - Richter, Rico A1 - Döllner, Jürgen Roland Friedrich T1 - Interactive and View-Dependent See-Through Lenses for Massive 3D Point Clouds JF - Advances in 3D Geoinformation N2 - 3D point clouds are a digital representation of our world and used in a variety of applications. They are captured with LiDAR or derived by image-matching approaches to get surface information of objects, e.g., indoor scenes, buildings, infrastructures, cities, and landscapes. We present novel interaction and visualization techniques for heterogeneous, time variant, and semantically rich 3D point clouds. Interactive and view-dependent see-through lenses are introduced as exploration tools to enhance recognition of objects, semantics, and temporal changes within 3D point cloud depictions. We also develop filtering and highlighting techniques that are used to dissolve occlusion to give context-specific insights. All techniques can be combined with an out-of-core real-time rendering system for massive 3D point clouds. We have evaluated the presented approach with 3D point clouds from different application domains. The results show the usability and how different visualization and exploration tasks can be improved for a variety of domain-specific applications. KW - 3D point clouds KW - LIDAR KW - Visualization KW - Point-based rendering Y1 - 2016 SN - 978-3-319-25691-7 SN - 978-3-319-25689-4 U6 - https://doi.org/10.1007/978-3-319-25691-7_3 SN - 1863-2246 SP - 49 EP - 62 PB - Springer CY - Cham ER - TY - BOOK A1 - Nienhaus, Marc A1 - Gooch, Bruce A1 - Döllner, Jürgen Roland Friedrich T1 - Visualizing movement dynamics in virtual urban environments N2 - Dynamics in urban environments encompasses complex processes and phenomena such as related to movement (e.g.,traffic, people) and development (e.g., construction, settlement). This paper presents novel methods for creating human-centric illustrative maps for visualizing the movement dynamics in virtual 3D environments. The methods allow a viewer to gain rapid insight into traffic density and flow. The illustrative maps represent vehicle behavior as light threads. Light threads are a familiar visual metaphor caused by moving light sources producing streaks in a long-exposure photograph. A vehicle’s front and rear lights produce light threads that convey its direction of motion as well as its velocity and acceleration. The accumulation of light threads allows a viewer to quickly perceive traffic flow and density. The light-thread technique is a key element to effective visualization systems for analytic reasoning, exploration, and monitoring of geospatial processes. T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 17 Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-33065 SN - 978-3-939469-52-0 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Buschmann, Stefan A1 - Trapp, Matthias A1 - Döllner, Jürgen Roland Friedrich T1 - Animated visualization of spatial-temporal trajectory data for air-traffic analysis JF - The Visual Computer N2 - With increasing numbers of flights worldwide and a continuing rise in airport traffic, air-traffic management is faced with a number of challenges. These include monitoring, reporting, planning, and problem analysis of past and current air traffic, e.g., to identify hotspots, minimize delays, or to optimize sector assignments to air-traffic controllers. To cope with these challenges, cyber worlds can be used for interactive visual analysis and analytical reasoning based on aircraft trajectory data. However, with growing data size and complexity, visualization requires high computational efficiency to process that data within real-time constraints. This paper presents a technique for real-time animated visualization of massive trajectory data. It enables (1) interactive spatio-temporal filtering, (2) generic mapping of trajectory attributes to geometric representations and appearance, and (3) real-time rendering within 3D virtual environments such as virtual 3D airport or 3D city models. Different visualization metaphors can be efficiently built upon this technique such as temporal focus+context, density maps, or overview+detail methods. As a general-purpose visualization technique, it can be applied to general 3D and 3+1D trajectory data, e.g., traffic movement data, geo-referenced networks, or spatio-temporal data, and it supports related visual analytics and data mining tasks within cyber worlds. KW - Spatio-temporal visualization KW - Trajectory visualization KW - 3D visualization KW - Visual analytics KW - Real-time rendering Y1 - 2016 U6 - https://doi.org/10.1007/s00371-015-1185-9 SN - 0178-2789 SN - 1432-2315 VL - 32 SP - 371 EP - 381 PB - Springer CY - New York ER - TY - BOOK A1 - Meinel, Christoph A1 - Plattner, Hasso A1 - Döllner, Jürgen Roland Friedrich A1 - Weske, Mathias A1 - Polze, Andreas A1 - Hirschfeld, Robert A1 - Naumann, Felix A1 - Giese, Holger A1 - Baudisch, Patrick T1 - Proceedings of the 7th Ph.D. Retreat of the HPI Research School on Service-oriented Systems Engineering N2 - Design and Implementation of service-oriented architectures imposes a huge number of research questions from the fields of software engineering, system analysis and modeling, adaptability, and application integration. Component orientation and web services are two approaches for design and realization of complex web-based system. Both approaches allow for dynamic application adaptation as well as integration of enterprise application. Commonly used technologies, such as J2EE and .NET, form de facto standards for the realization of complex distributed systems. Evolution of component systems has lead to web services and service-based architectures. This has been manifested in a multitude of industry standards and initiatives such as XML, WSDL UDDI, SOAP, etc. All these achievements lead to a new and promising paradigm in IT systems engineering which proposes to design complex software solutions as collaboration of contractually defined software services. Service-Oriented Systems Engineering represents a symbiosis of best practices in object-orientation, component-based development, distributed computing, and business process management. It provides integration of business and IT concerns. The annual Ph.D. Retreat of the Research School provides each member the opportunity to present his/her current state of their research and to give an outline of a prospective Ph.D. thesis. Due to the interdisciplinary structure of the Research Scholl, this technical report covers a wide range of research topics. These include but are not limited to: Self-Adaptive Service-Oriented Systems, Operating System Support for Service-Oriented Systems, Architecture and Modeling of Service-Oriented Systems, Adaptive Process Management, Services Composition and Workflow Planning, Security Engineering of Service-Based IT Systems, Quantitative Analysis and Optimization of Service-Oriented Systems, Service-Oriented Systems in 3D Computer Graphics sowie Service-Oriented Geoinformatics. N2 - Der Entwurf und die Realisierung dienstbasierender Architekturen wirft eine Vielzahl von Forschungsfragestellungen aus den Gebieten der Softwaretechnik, der Systemmodellierung und -analyse, sowie der Adaptierbarkeit und Integration von Applikationen auf. Komponentenorientierung und WebServices sind zwei Ansätze für den effizienten Entwurf und die Realisierung komplexer Web-basierender Systeme. Sie ermöglichen die Reaktion auf wechselnde Anforderungen ebenso, wie die Integration großer komplexer Softwaresysteme. Heute übliche Technologien, wie J2EE und .NET, sind de facto Standards für die Entwicklung großer verteilter Systeme. Die Evolution solcher Komponentensysteme führt über WebServices zu dienstbasierenden Architekturen. Dies manifestiert sich in einer Vielzahl von Industriestandards und Initiativen wie XML, WSDL, UDDI, SOAP. All diese Schritte führen letztlich zu einem neuen, vielversprechenden Paradigma für IT Systeme, nach dem komplexe Softwarelösungen durch die Integration vertraglich vereinbarter Software-Dienste aufgebaut werden sollen. "Service-Oriented Systems Engineering" repräsentiert die Symbiose bewährter Praktiken aus den Gebieten der Objektorientierung, der Komponentenprogrammierung, des verteilten Rechnen sowie der Geschäftsprozesse und berücksichtigt auch die Integration von Geschäftsanliegen und Informationstechnologien. Die Klausurtagung des Forschungskollegs "Service-oriented Systems Engineering" findet einmal jährlich statt und bietet allen Kollegiaten die Möglichkeit den Stand ihrer aktuellen Forschung darzulegen. Bedingt durch die Querschnittstruktur des Kollegs deckt dieser Bericht ein große Bandbreite aktueller Forschungsthemen ab. Dazu zählen unter anderem Self-Adaptive Service-Oriented Systems, Operating System Support for Service-Oriented Systems, Architecture and Modeling of Service-Oriented Systems, Adaptive Process Management, Services Composition and Workflow Planning, Security Engineering of Service-Based IT Systems, Quantitative Analysis and Optimization of Service-Oriented Systems, Service-Oriented Systems in 3D Computer Graphics sowie Service-Oriented Geoinformatics. T3 - Technische Berichte des Hasso-Plattner-Instituts für Digital Engineering an der Universität Potsdam - 83 KW - Hasso-Plattner-Institut KW - Forschungskolleg KW - Klausurtagung KW - Service-oriented Systems Engineering KW - Hasso Plattner Institute KW - Research School KW - Ph.D. Retreat KW - Service-oriented Systems Engineering Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-63490 SN - 978-3-86956-273-5 PB - Universitätsverlag Potsdam CY - Potsdam ER -