TY - JOUR A1 - Delgrande, James A1 - Schaub, Torsten H. A1 - Tompits, Hans A1 - Woltran, Stefan T1 - A model-theoretic approach to belief change in answer set programming JF - ACM transactions on computational logic N2 - We address the problem of belief change in (nonmonotonic) logic programming under answer set semantics. Our formal techniques are analogous to those of distance-based belief revision in propositional logic. In particular, we build upon the model theory of logic programs furnished by SE interpretations, where an SE interpretation is a model of a logic program in the same way that a classical interpretation is a model of a propositional formula. Hence we extend techniques from the area of belief revision based on distance between models to belief change in logic programs. We first consider belief revision: for logic programs P and Q, the goal is to determine a program R that corresponds to the revision of P by Q, denoted P * Q. We investigate several operators, including (logic program) expansion and two revision operators based on the distance between the SE models of logic programs. It proves to be the case that expansion is an interesting operator in its own right, unlike in classical belief revision where it is relatively uninteresting. Expansion and revision are shown to satisfy a suite of interesting properties; in particular, our revision operators satisfy all or nearly all of the AGM postulates for revision. We next consider approaches for merging a set of logic programs, P-1,...,P-n. Again, our formal techniques are based on notions of relative distance between the SE models of the logic programs. Two approaches are examined. The first informally selects for each program P-i those models of P-i that vary the least from models of the other programs. The second approach informally selects those models of a program P-0 that are closest to the models of programs P-1,...,P-n. In this case, P-0 can be thought of as a set of database integrity constraints. We examine these operators with regards to how they satisfy relevant postulate sets. Last, we present encodings for computing the revision as well as the merging of logic programs within the same logic programming framework. This gives rise to a direct implementation of our approach in terms of off-the-shelf answer set solvers. These encodings also reflect the fact that our change operators do not increase the complexity of the base formalism. KW - Theory KW - Answer set programming KW - belief revision KW - belief merging KW - program encodings KW - strong equivalence Y1 - 2013 U6 - https://doi.org/10.1145/2480759.2480766 SN - 1529-3785 VL - 14 IS - 2 PB - Association for Computing Machinery CY - New York ER - TY - BOOK A1 - Knobelsdorf, Maria A1 - Kreitz, Christoph T1 - Ein konstruktivistischer Lehransatz für die Einführungsveranstaltung der Theoretische Informatik Y1 - 2013 SN - 978-3-86956-220-9 ER - TY - JOUR A1 - Delikostidis, Ioannis A1 - Engel, Juri A1 - Retsios, Bas A1 - van Elzakker, Corne P. J. M. A1 - Kraak, Menno-Jan A1 - Döllner, Jürgen Roland Friedrich T1 - Increasing the usability of pedestrian navigation interfaces by means of landmark visibility analysis JF - The journal of navigation 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. KW - Pedestrian navigation KW - Landmark visibility KW - User-centred design KW - Usability testing Y1 - 2013 U6 - https://doi.org/10.1017/S0373463313000209 SN - 0373-4633 VL - 66 IS - 4 SP - 523 EP - 537 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Richter, Rico A1 - Kyprianidis, Jan Eric A1 - Döllner, Jürgen Roland Friedrich T1 - Out-of-core GPU-based change detection in massive 3D point clouds JF - Transactions in GIS N2 - If sites, cities, and landscapes are captured at different points in time using technology such as LiDAR, large collections of 3D point clouds result. Their efficient storage, processing, analysis, and presentation constitute a challenging task because of limited computation, memory, and time resources. In this work, we present an approach to detect changes in massive 3D point clouds based on an out-of-core spatial data structure that is designed to store data acquired at different points in time and to efficiently attribute 3D points with distance information. Based on this data structure, we present and evaluate different processing schemes optimized for performing the calculation on the CPU and GPU. In addition, we present a point-based rendering technique adapted for attributed 3D point clouds, to enable effective out-of-core real-time visualization of the computation results. Our approach enables conclusions to be drawn about temporal changes in large highly accurate 3D geodata sets of a captured area at reasonable preprocessing and rendering times. We evaluate our approach with two data sets from different points in time for the urban area of a city, describe its characteristics, and report on applications. Y1 - 2013 U6 - https://doi.org/10.1111/j.1467-9671.2012.01362.x SN - 1361-1682 VL - 17 IS - 5 SP - 724 EP - 741 PB - Wiley-Blackwell CY - Hoboken ER - TY - THES A1 - Yang, Haojin T1 - Automatic video indexing and retrieval using video ocr technology Y1 - 2013 CY - Potsdam ER - TY - JOUR A1 - Steinert, Bastian A1 - Cassou, Damien A1 - Hirschfeld, Robert T1 - CoExist overcoming aversion to change preserving immediate access to source code and run-time information of previous development states JF - ACM SIGPLAN notices N2 - Programmers make many changes to the program to eventually find a good solution for a given task. In this course of change, every intermediate development state can of value, when, for example, a promising ideas suddenly turn out inappropriate or the interplay of objects turns out more complex than initially expected before making changes. Programmers would benefit from tool support that provides immediate access to source code and run-time of previous development states of interest. We present IDE extensions, implemented for Squeak/Smalltalk, to preserve, retrieve, and work with this information. With such tool support, programmers can work without worries because they can rely on tools that help them with whatever their explorations will reveal. They no longer have to follow certain best practices only to avoid undesired consequences of changing code. KW - Design KW - Experimentation KW - Human Factors KW - Continuous Testing KW - Continuous Versioning KW - Debugging KW - Evolution KW - Explore-first Programming KW - Fault Localization KW - Prototyping Y1 - 2013 U6 - https://doi.org/10.1145/2480360.2384591 SN - 0362-1340 VL - 48 IS - 2 SP - 107 EP - 117 PB - Association for Computing Machinery CY - New York ER - TY - THES A1 - Gros, Oliver T1 - Computergestützte Wissensextraktion aus befundtexten der Pathologie Y1 - 2013 CY - Potsdam ER - TY - BOOK A1 - Al-Saffar, Loay Talib Ahmed T1 - Where girls the role of boys in CS - attitudes of CS students in a female-dominated environment Y1 - 2013 SN - 978-3-86956-220-9 ER - TY - THES A1 - Neumann, Stefan T1 - Modular timing analysis of component-based real-time embedded systems Y1 - 2013 CY - Potsdam ER - TY - JOUR A1 - van Hooland, Seth A1 - Verborgh, Ruben A1 - De Wilde, Max A1 - Hercher, Johannes A1 - Mannens, Erik A1 - Van de Walle, Rik T1 - Evaluating the success of vocabulary reconciliation for cultural heritage collections JF - Journal of the American Society for Information Science and Technology N2 - The concept of Linked Data has made its entrance in the cultural heritage sector due to its potential use for the integration of heterogeneous collections and deriving additional value out of existing metadata. However, practitioners and researchers alike need a better understanding of what outcome they can reasonably expect of the reconciliation process between their local metadata and established controlled vocabularies which are already a part of the Linked Data cloud. This paper offers an in-depth analysis of how a locally developed vocabulary can be successfully reconciled with the Library of Congress Subject Headings (LCSH) and the Arts and Architecture Thesaurus (AAT) through the help of a general-purpose tool for interactive data transformation (OpenRefine). Issues negatively affecting the reconciliation process are identified and solutions are proposed in order to derive maximum value from existing metadata and controlled vocabularies in an automated manner. KW - semantic web KW - metadata KW - controlled vocabularies Y1 - 2013 U6 - https://doi.org/10.1002/asi.22763 SN - 1532-2882 VL - 64 IS - 3 SP - 464 EP - 479 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Montavon, Gregoire A1 - Braun, Mikio L. A1 - Krüger, Tammo A1 - Müller, Klaus-Robert T1 - Analyzing local structure in Kernel-Based learning JF - IEEE signal processing magazine Y1 - 2013 U6 - https://doi.org/10.1109/MSP.2013.2249294 SN - 1053-5888 VL - 30 IS - 4 SP - 62 EP - 74 PB - Inst. of Electr. and Electronics Engineers CY - Piscataway ER - TY - JOUR A1 - Gebser, Martin A1 - Schaub, Torsten H. T1 - Tableau calculi for logic programs under answer set semantics JF - ACM transactions on computational logic N2 - We introduce formal proof systems based on tableau methods for analyzing computations in Answer Set Programming (ASP). Our approach furnishes fine-grained instruments for characterizing operations as well as strategies of ASP solvers. The granularity is detailed enough to capture a variety of propagation and choice methods of algorithms used for ASP solving, also incorporating SAT-based and conflict-driven learning approaches to some extent. This provides us with a uniform setting for identifying and comparing fundamental properties of ASP solving approaches. In particular, we investigate their proof complexities and show that the run-times of best-case computations can vary exponentially between different existing ASP solvers. Apart from providing a framework for comparing ASP solving approaches, our characterizations also contribute to their understanding by pinning down the constitutive atomic operations. Furthermore, our framework is flexible enough to integrate new inference patterns, and so to study their relation to existing ones. To this end, we generalize our approach and provide an extensible basis aiming at a modular incorporation of additional language constructs. This is exemplified by augmenting our basic tableau methods with cardinality constraints and disjunctions. KW - Theory KW - Answer Set Programming KW - tableau calculi KW - proof complexity Y1 - 2013 U6 - https://doi.org/10.1145/2480759.2480767 SN - 1529-3785 VL - 14 IS - 2 PB - Association for Computing Machinery CY - New York ER - TY - THES A1 - Phusanga, Dara T1 - Derived algebraic systems Y1 - 2013 CY - Potsdam ER - TY - JOUR A1 - Guziolowski, Carito A1 - Videla, Santiago A1 - Eduati, Federica A1 - Thiele, Sven A1 - Cokelaer, Thomas A1 - Siegel, Anne A1 - Saez-Rodriguez, Julio T1 - Exhaustively characterizing feasible logic models of a signaling network using Answer Set Programming JF - Bioinformatics N2 - Motivation: Logic modeling is a useful tool to study signal transduction across multiple pathways. Logic models can be generated by training a network containing the prior knowledge to phospho-proteomics data. The training can be performed using stochastic optimization procedures, but these are unable to guarantee a global optima or to report the complete family of feasible models. This, however, is essential to provide precise insight in the mechanisms underlaying signal transduction and generate reliable predictions. Results: We propose the use of Answer Set Programming to explore exhaustively the space of feasible logic models. Toward this end, we have developed caspo, an open-source Python package that provides a powerful platform to learn and characterize logic models by leveraging the rich modeling language and solving technologies of Answer Set Programming. We illustrate the usefulness of caspo by revisiting a model of pro-growth and inflammatory pathways in liver cells. We show that, if experimental error is taken into account, there are thousands (11 700) of models compatible with the data. Despite the large number, we can extract structural features from the models, such as links that are always (or never) present or modules that appear in a mutual exclusive fashion. To further characterize this family of models, we investigate the input-output behavior of the models. We find 91 behaviors across the 11 700 models and we suggest new experiments to discriminate among them. Our results underscore the importance of characterizing in a global and exhaustive manner the family of feasible models, with important implications for experimental design. Y1 - 2013 U6 - https://doi.org/10.1093/bioinformatics/btt393 SN - 1367-4803 VL - 29 IS - 18 SP - 2320 EP - 2326 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Floyd, Barry D. A1 - Bosselmann, Steve T1 - ITSy-simplicity research in information and communication technology JF - Computer : innovative technology for computer professionals N2 - Basic to information and communication technology design, simplicity as a driving concept receives little formal attention from the ICT community. A recent literature review and survey of scholars, researchers, and practitioners conducted through the Information Technology Simply Works (ITSy) European Support Action reveals key findings about current perceptions of and future directions for simplicity in ICT. Y1 - 2013 SN - 0018-9162 SN - 1558-0814 VL - 46 IS - 11 SP - 26 EP - 32 PB - Inst. of Electr. and Electronics Engineers CY - Los Alamitos ER - TY - THES A1 - Schaffner, Jan T1 - Multi tenancy for cloud-based in-memory column databases : workload management and data placement Y1 - 2013 CY - Potsdam ER - TY - INPR A1 - Margaria, Tiziana A1 - Hinchey, Mike T1 - Simplicity in IT - the power of less T2 - Computer : innovative technology for computer professionals N2 - Simplicity is a mindset, a way of looking at solutions, an extremely wide-ranging philosophical stance on the world, and thus a deeply rooted cultural paradigm. The culture of "less" can be profoundly disruptive, cutting out existing "standard" elements from products and business models, thereby revolutionizing entire markets. Y1 - 2013 U6 - https://doi.org/10.1109/MC.2013.397 SN - 0018-9162 SN - 1558-0814 VL - 46 IS - 11 SP - 23 EP - 25 PB - Inst. of Electr. and Electronics Engineers CY - Los Alamitos ER - TY - THES A1 - Alsadeh, Ahmad T1 - Augmented secure neighbor discovery: aligning security, privacy and usability Y1 - 2013 CY - Potsdam ER - TY - JOUR A1 - Kaminski, Roland A1 - Schaub, Torsten H. A1 - Siegel, Anne A1 - Videla, Santiago T1 - Minimal intervention strategies in logical signaling networks with ASP JF - Theory and practice of logic programming N2 - Proposing relevant perturbations to biological signaling networks is central to many problems in biology and medicine because it allows for enabling or disabling certain biological outcomes. In contrast to quantitative methods that permit fine-grained (kinetic) analysis, qualitative approaches allow for addressing large-scale networks. This is accomplished by more abstract representations such as logical networks. We elaborate upon such a qualitative approach aiming at the computation of minimal interventions in logical signaling networks relying on Kleene's three-valued logic and fixpoint semantics. We address this problem within answer set programming and show that it greatly outperforms previous work using dedicated algorithms. Y1 - 2013 U6 - https://doi.org/10.1017/S1471068413000422 SN - 1471-0684 VL - 13 SP - 675 EP - 690 PB - Cambridge Univ. Press CY - New York ER - TY - THES A1 - Hentschel, Uwe T1 - Steuerung der Datenübertragung in öffentlichen zellularen Funknetzen im Kontext telemedizinischer Anwendung Y1 - 2013 CY - Potsdam ER -