@phdthesis{AlAreqi2017, author = {Al-Areqi, Samih Taha Mohammed}, title = {Semantics-based automatic geospatial service composition}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-402616}, school = {Universit{\"a}t Potsdam}, pages = {xvi, 163}, year = {2017}, abstract = {Although it has become common practice to build applications based on the reuse of existing components or services, technical complexity and semantic challenges constitute barriers to ensuring a successful and wide reuse of components and services. In the geospatial application domain, the barriers are self-evident due to heterogeneous geographic data, a lack of interoperability and complex analysis processes. Constructing workflows manually and discovering proper services and data that match user intents and preferences is difficult and time-consuming especially for users who are not trained in software development. Furthermore, considering the multi-objective nature of environmental modeling for the assessment of climate change impacts and the various types of geospatial data (e.g., formats, scales, and georeferencing systems) increases the complexity challenges. Automatic service composition approaches that provide semantics-based assistance in the process of workflow design have proven to be a solution to overcome these challenges and have become a frequent demand especially by end users who are not IT experts. In this light, the major contributions of this thesis are: (i) Simplification of service reuse and workflow design of applications for climate impact analysis by following the eXtreme Model-Driven Development (XMDD) paradigm. (ii) Design of a semantic domain model for climate impact analysis applications that comprises specifically designed services, ontologies that provide domain-specific vocabulary for referring to types and services, and the input/output annotation of the services using the terms defined in the ontologies. (iii) Application of a constraint-driven method for the automatic composition of workflows for analyzing the impacts of sea-level rise. The application scenario demonstrates the impact of domain modeling decisions on the results and the performance of the synthesis algorithm.}, language = {en} } @article{GoetzBrinda2013, author = {G{\"o}tz, Christian and Brinda, Torsten}, title = {Sind soziale Netzwerke geeignet, um darin f{\"u}r Informatikstudieng{\"a}nge zu werben?}, series = {Commentarii informaticae didacticae : (CID)}, journal = {Commentarii informaticae didacticae : (CID)}, number = {5}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-65017}, pages = {137 -- 142}, year = {2013}, abstract = {Durch den bundesweiten R{\"u}ckgang der Sch{\"u}lerzahlen und einer steigenden Zahl von Bildungsangeboten geraten Universit{\"a}ten und Hochschulen in den n{\"a}chsten Jahren weiter in eine Wettbewerbssituation, weshalb sie effektive Marketingmaßnahmen entwickeln m{\"u}ssen, um Sch{\"u}lerinnen und Sch{\"u}ler m{\"o}glichst fr{\"u}hzeitig f{\"u}r das jeweilige Angebot (z. B. Informatik- und informatiknahe Studieng{\"a}nge) zu interessieren. Ein Medium, {\"u}ber das sich potenziell sehr viele Jugendliche erreichen lassen, sind dabei soziale Netzwerke. Diese Arbeit pr{\"a}sentiert Ergebnisse einer Studie unter Informatikstudienanf{\"a}ngerinnen und -anf{\"a}ngern zum Nutzungsverhalten sozialer Netzwerke und zieht Schlussfolgerungen zu deren Eignung als Werbe- und Informationskanal f{\"u}r die Zielgruppe der Informatikinteressierten.}, language = {de} } @phdthesis{Prohaska2007, author = {Prohaska, Steffen}, title = {Skeleton-based visualization of massive voxel objects with network-like architecture}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-14888}, school = {Universit{\"a}t Potsdam}, year = {2007}, abstract = {This work introduces novel internal and external memory algorithms for computing voxel skeletons of massive voxel objects with complex network-like architecture and for converting these voxel skeletons to piecewise linear geometry, that is triangle meshes and piecewise straight lines. The presented techniques help to tackle the challenge of visualizing and analyzing 3d images of increasing size and complexity, which are becoming more and more important in, for example, biological and medical research. Section 2.3.1 contributes to the theoretical foundations of thinning algorithms with a discussion of homotopic thinning in the grid cell model. The grid cell model explicitly represents a cell complex built of faces, edges, and vertices shared between voxels. A characterization of pairs of cells to be deleted is much simpler than characterizations of simple voxels were before. The grid cell model resolves topologically unclear voxel configurations at junctions and locked voxel configurations causing, for example, interior voxels in sets of non-simple voxels. A general conclusion is that the grid cell model is superior to indecomposable voxels for algorithms that need detailed control of topology. Section 2.3.2 introduces a noise-insensitive measure based on the geodesic distance along the boundary to compute two-dimensional skeletons. The measure is able to retain thin object structures if they are geometrically important while ignoring noise on the object's boundary. This combination of properties is not known of other measures. The measure is also used to guide erosion in a thinning process from the boundary towards lines centered within plate-like structures. Geodesic distance based quantities seem to be well suited to robustly identify one- and two-dimensional skeletons. Chapter 6 applies the method to visualization of bone micro-architecture. Chapter 3 describes a novel geometry generation scheme for representing voxel skeletons, which retracts voxel skeletons to piecewise linear geometry per dual cube. The generated triangle meshes and graphs provide a link to geometry processing and efficient rendering of voxel skeletons. The scheme creates non-closed surfaces with boundaries, which contain fewer triangles than a representation of voxel skeletons using closed surfaces like small cubes or iso-surfaces. A conclusion is that thinking specifically about voxel skeleton configurations instead of generic voxel configurations helps to deal with the topological implications. The geometry generation is one foundation of the applications presented in Chapter 6. Chapter 5 presents a novel external memory algorithm for distance ordered homotopic thinning. The presented method extends known algorithms for computing chamfer distance transformations and thinning to execute I/O-efficiently when input is larger than the available main memory. The applied block-wise decomposition schemes are quite simple. Yet it was necessary to carefully analyze effects of block boundaries to devise globally correct external memory variants of known algorithms. In general, doing so is superior to naive block-wise processing ignoring boundary effects. Chapter 6 applies the algorithms in a novel method based on confocal microscopy for quantitative study of micro-vascular networks in the field of microcirculation.}, language = {en} } @article{LuckeHaferHartmann2020, author = {Lucke, Ulrike and Hafer, J{\"o}rg and Hartmann, Niklas}, title = {Strategieentwicklung in der Hochschule als partizipativer Prozess}, series = {Potsdamer Beitr{\"a}ge zur Hochschulforschung}, journal = {Potsdamer Beitr{\"a}ge zur Hochschulforschung}, number = {6}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-498-2}, issn = {2192-1075}, doi = {10.25932/publishup-49276}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-492764}, pages = {99 -- 117}, year = {2020}, abstract = {Die Setzung strategischer Ziele sowie die Zuordnung und Umsetzung dazugeh{\"o}render Maßnahmen sind ein wesentliches Element, um die Innovationsf{\"a}higkeit von Organisationen zu erhalten. In den vergangenen Jahren ist auch an Hochschulen die Strategiebildung deutlich vorangetrieben worden. Dies betrifft verschiedene Handlungsfelder, und es werden verschiedene Ans{\"a}tze verfolgt. Der vorliegende Beitrag greift am Beispiel der Universit{\"a}t Potsdam drei in den vergangenen Jahren adressierte Strategiebereiche heraus: IT, E-Learning und Forschungsdaten. Die damit verbundenen Prozesse waren in unterschiedlichem Maß von Partizipation gepr{\"a}gt. Die gesammelten Erfahrungen werden reflektiert, und es werden Empfehlungen f{\"u}r Strategieentwicklungsprozesse abgeleitet.}, language = {de} } @phdthesis{Kyprianidis2013, author = {Kyprianidis, Jan Eric}, title = {Structure adaptive stylization of images and video}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-64104}, school = {Universit{\"a}t Potsdam}, year = {2013}, abstract = {In the early days of computer graphics, research was mainly driven by the goal to create realistic synthetic imagery. By contrast, non-photorealistic computer graphics, established as its own branch of computer graphics in the early 1990s, is mainly motivated by concepts and principles found in traditional art forms, such as painting, illustration, and graphic design, and it investigates concepts and techniques that abstract from reality using expressive, stylized, or illustrative rendering techniques. This thesis focuses on the artistic stylization of two-dimensional content and presents several novel automatic techniques for the creation of simplified stylistic illustrations from color images, video, and 3D renderings. Primary innovation of these novel techniques is that they utilize the smooth structure tensor as a simple and efficient way to obtain information about the local structure of an image. More specifically, this thesis contributes to knowledge in this field in the following ways. First, a comprehensive review of the structure tensor is provided. In particular, different methods for integrating the minor eigenvector field of the smoothed structure tensor are developed, and the superiority of the smoothed structure tensor over the popular edge tangent flow is demonstrated. Second, separable implementations of the popular bilateral and difference of Gaussians filters that adapt to the local structure are presented. These filters avoid artifacts while being computationally highly efficient. Taken together, both provide an effective way to create a cartoon-style effect. Third, a generalization of the Kuwahara filter is presented that avoids artifacts by adapting the shape, scale, and orientation of the filter to the local structure. This causes directional image features to be better preserved and emphasized, resulting in overall sharper edges and a more feature-abiding painterly effect. In addition to the single-scale variant, a multi-scale variant is presented, which is capable of performing a highly aggressive abstraction. Fourth, a technique that builds upon the idea of combining flow-guided smoothing with shock filtering is presented, allowing for an aggressive exaggeration and an emphasis of directional image features. All presented techniques are suitable for temporally coherent per-frame filtering of video or dynamic 3D renderings, without requiring expensive extra processing, such as optical flow. Moreover, they can be efficiently implemented to process content in real-time on a GPU.}, language = {en} } @phdthesis{Polyvyanyy2012, author = {Polyvyanyy, Artem}, title = {Structuring process models}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-59024}, school = {Universit{\"a}t Potsdam}, year = {2012}, abstract = {One can fairly adopt the ideas of Donald E. Knuth to conclude that process modeling is both a science and an art. Process modeling does have an aesthetic sense. Similar to composing an opera or writing a novel, process modeling is carried out by humans who undergo creative practices when engineering a process model. Therefore, the very same process can be modeled in a myriad number of ways. Once modeled, processes can be analyzed by employing scientific methods. Usually, process models are formalized as directed graphs, with nodes representing tasks and decisions, and directed arcs describing temporal constraints between the nodes. Common process definition languages, such as Business Process Model and Notation (BPMN) and Event-driven Process Chain (EPC) allow process analysts to define models with arbitrary complex topologies. The absence of structural constraints supports creativity and productivity, as there is no need to force ideas into a limited amount of available structural patterns. Nevertheless, it is often preferable that models follow certain structural rules. A well-known structural property of process models is (well-)structuredness. A process model is (well-)structured if and only if every node with multiple outgoing arcs (a split) has a corresponding node with multiple incoming arcs (a join), and vice versa, such that the set of nodes between the split and the join induces a single-entry-single-exit (SESE) region; otherwise the process model is unstructured. The motivations for well-structured process models are manifold: (i) Well-structured process models are easier to layout for visual representation as their formalizations are planar graphs. (ii) Well-structured process models are easier to comprehend by humans. (iii) Well-structured process models tend to have fewer errors than unstructured ones and it is less probable to introduce new errors when modifying a well-structured process model. (iv) Well-structured process models are better suited for analysis with many existing formal techniques applicable only for well-structured process models. (v) Well-structured process models are better suited for efficient execution and optimization, e.g., when discovering independent regions of a process model that can be executed concurrently. Consequently, there are process modeling languages that encourage well-structured modeling, e.g., Business Process Execution Language (BPEL) and ADEPT. However, the well-structured process modeling implies some limitations: (i) There exist processes that cannot be formalized as well-structured process models. (ii) There exist processes that when formalized as well-structured process models require a considerable duplication of modeling constructs. Rather than expecting well-structured modeling from start, we advocate for the absence of structural constraints when modeling. Afterwards, automated methods can suggest, upon request and whenever possible, alternative formalizations that are "better" structured, preferably well-structured. In this thesis, we study the problem of automatically transforming process models into equivalent well-structured models. The developed transformations are performed under a strong notion of behavioral equivalence which preserves concurrency. The findings are implemented in a tool, which is publicly available.}, language = {en} } @article{EllisAbreuEllis2015, author = {Ellis, Jason Brent and Abreu-Ellis, Carla Reis}, title = {Student Perspectives of Social Networking use in Higher Education}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82632}, pages = {117 -- 131}, year = {2015}, abstract = {Social networks are currently at the forefront of tools that lend to Personal Learning Environments (PLEs). This study aimed to observe how students perceived PLEs, what they believed were the integral components of social presence when using Facebook as part of a PLE, and to describe student's preferences for types of interactions when using Facebook as part of their PLE. This study used mixed methods to analyze the perceptions of graduate and undergraduate students on the use of social networks, more specifically Facebook as a learning tool. Fifty surveys were returned representing a 65 \% response rate. Survey questions included both closed and open-ended questions. Findings suggested that even though students rated themselves relatively well in having requisite technology skills, and 94 \% of students used Facebook primarily for social use, they were hesitant to migrate these skills to academic use because of concerns of privacy, believing that other platforms could fulfil the same purpose, and by not seeing the validity to use Facebook in establishing social presence. What lies at odds with these beliefs is that when asked to identify strategies in Facebook that enabled social presence to occur in academic work, the majority of students identified strategies in five categories that lead to social presence establishment on Facebook during their coursework.}, language = {en} } @article{KlingerPolutinaBibel2013, author = {Klinger, Melanie and Polutina, Olena and Bibel, Ariane}, title = {Studentische eLearning-Beratung}, series = {Commentarii informaticae didacticae : (CID)}, journal = {Commentarii informaticae didacticae : (CID)}, number = {5}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-65003}, pages = {131 -- 136}, year = {2013}, abstract = {Der vorliegende Beitrag besch{\"a}ftigt sich mit der Frage, wie der eLearning-Support in großen Institutionen effizient gestaltet werden kann. Vorgestellt wird ein experimentelles Beratungsprojekt, das Lehrende bei der Gestaltung von eLearning-Maßnahmen mithilfe der Lernplattform ILIAS1 unterst{\"u}tzt. Neben der Zielsetzung des Projekts werden dessen Aufbau und erste Praxiserfahrungen er{\"o}rtert. Außerdem werden Potenziale des Beratungsformats, die insbesondere mit der individuellen Vor-Ort-Beratung der Lehrenden durch hochschuldidaktisch geschulte Studierende einhergehen, erl{\"a}utert. Abschließend werden Grenzen und Weiterentwicklungsperspektiven des Projekts dargestellt. Am Beispiel der ILIAS-Beratung soll gezeigt werden, dass es sich einer nachhaltigen Organisationsentwicklung als zutr{\"a}glich erweist, Kooperationen erschiedenartiger Organisationseinheiten zu f{\"o}rdern und die entstehenden Synergieeffekte zu nutzen.}, language = {de} } @article{LeonhardtKwiecienSchmetzetal.2015, author = {Leonhardt, Thiemo and Kwiecien, Alexandra and Schmetz, Arno and Bellgardt, Martin and Naumann, Uwe}, title = {Studienabbruchsquote dauerhaft senken}, series = {HDI 2014 : Gestalten von {\"U}berg{\"a}ngen}, volume = {2015}, journal = {HDI 2014 : Gestalten von {\"U}berg{\"a}ngen}, number = {9}, editor = {Schwill, Andreas and Schubert, Sigrid}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-80274}, pages = {61 -- 76}, year = {2015}, abstract = {Es wird ein umfassendes Mentoring Konzept im Studiengang Informatik an der RWTH Aachen vorgestellt, das den {\"U}bergang von der Schule zur Universit{\"a}t unterst{\"u}tzt und gleichzeitig beim Auftreten von Schwierigkeiten im Verlauf des Studiums effiziente und kompetente Beratung bietet. Das Programm erreicht durchg{\"a}ngig hohe Akzeptanzwerte bei den Studierenden trotz verpflichtender Teilnahme im ersten Semester. Die Wirksamkeit des Programms ist durch die zahlreichen einflussgebenden Variablen zwar rein quantitativ kaum messbar, die M{\"o}glichkeit auf organisatorische und fachliche Probleme eines Jahrgangs reagieren zu k{\"o}nnen sowie einen Einblick auf die Gr{\"u}nde f{\"u}r einen Studienabbruch zu bekommen, best{\"a}tigt aber die Notwendigkeit der Maßnahme.}, language = {de} } @article{LewinMcNicol2015, author = {Lewin, Cathy and McNicol, Sarah}, title = {Supporting the Development of 21st Century Skills through ICT}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82672}, pages = {181 -- 198}, year = {2015}, abstract = {The growing impact of globalisation and the development of a 'knowledge society' have led many to argue that 21st century skills are essential for life in twenty-first century society and that ICT is central to their development. This paper describes how 21st century skills, in particular digital literacy, critical thinking, creativity, communication and collaboration skills, have been conceptualised and embedded in the resources developed for teachers in iTEC, a four-year, European project. The effectiveness of this approach is considered in light of the data collected through the evaluation of the pilots, which considers both the potential benefits of using technology to support the development of 21st century skills, but also the challenges of doing so. Finally, the paper discusses the learning support systems required in order to transform pedagogies and embed 21st century skills. It is argued that support is required in standards and assessment; curriculum and instruction; professional development; and learning environments.}, language = {en} } @article{EhlenzBergnerSchroeder2016, author = {Ehlenz, Matthias and Bergner, Nadine and Schroeder, Ulrik}, title = {Synergieeffekte zwischen Fach- und Lehramtsstudierenden in Softwarepraktika}, series = {Commentarii informaticae didacticae (CID)}, journal = {Commentarii informaticae didacticae (CID)}, number = {10}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-376-3}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-94875}, pages = {99 -- 102}, year = {2016}, abstract = {Dieser Beitrag diskutiert die Konzeption eines Software-Projektpraktikums im Bereich E-Learning, welches Lehramts- und Fachstudierenden der Informatik erm{\"o}glicht, voneinander zu profitieren und praxisrelevante Ergebnisse generiert. Vorbereitungen, Organisation und Durchf{\"u}hrung werden vorgestellt und diskutiert. Den Abschluss bildet ein Ausblick auf die Fortf{\"u}hrung des Konzepts und den Ausbau des Forschungsgebietes.}, language = {de} } @article{LaiDavisEickelmannetal.2015, author = {Lai, Kwok-Wing and Davis, Niki and Eickelmann, Birgit and Erstad, Ola and Fisser, Petra and Gibson, David and Khaddage, Ferial and Knezek, Gerald and Webb, Mary}, title = {Tackling Educational Challenges in a Digitally Networked World}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82997}, pages = {415 -- 423}, year = {2015}, language = {en} } @article{BarnesKennewell2015, author = {Barnes, Jan and Kennewell, Steve}, title = {Teacher Perceptions of Key Competencies in ICT}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82604}, pages = {61 -- 75}, year = {2015}, abstract = {Regardless of what is intended by government curriculum specifications and advised by educational experts, the competencies taught and learned in and out of classrooms can vary considerably. In this paper, we discuss in particular how we can investigate the perceptions that individual teachers have of competencies in ICT, and how these and other factors may influence students' learning. We report case study research which identifies contradictions within the teaching of ICT competencies as an activity system, highlighting issues concerning the object of the curriculum, the roles of the participants and the school cultures. In a particular case, contradictions in the learning objectives between higher order skills and the use of application tools have been resolved by a change in the teacher's perceptions which have not led to changes in other aspects of the activity system. We look forward to further investigation of the effects of these contradictions in other case studies and on forthcoming curriculum change.}, language = {en} } @article{GrillenbergerRomeike2015, author = {Grillenberger, Andreas and Romeike, Ralf}, title = {Teaching Data Management}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82648}, pages = {133 -- 150}, year = {2015}, abstract = {Data management is a central topic in computer science as well as in computer science education. Within the last years, this topic is changing tremendously, as its impact on daily life becomes increasingly visible. Nowadays, everyone not only needs to manage data of various kinds, but also continuously generates large amounts of data. In addition, Big Data and data analysis are intensively discussed in public dialogue because of their influences on society. For the understanding of such discussions and for being able to participate in them, fundamental knowledge on data management is necessary. Especially, being aware of the threats accompanying the ability to analyze large amounts of data in nearly real-time becomes increasingly important. This raises the question, which key competencies are necessary for daily dealings with data and data management. In this paper, we will first point out the importance of data management and of Big Data in daily life. On this basis, we will analyze which are the key competencies everyone needs concerning data management to be able to handle data in a proper way in daily life. Afterwards, we will discuss the impact of these changes in data management on computer science education and in particular database education.}, language = {en} } @article{Schiller2015, author = {Schiller, Thomas}, title = {Teaching Information Security (as Part of Key Competencies)}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82960}, pages = {401 -- 404}, year = {2015}, abstract = {The poster and abstract describe the importance of teaching information security in school. After a short description of information security and important aspects, I will show, how information security fits into different guidelines or models for computer science educations and that it is therefore on of the key competencies. Afterwards I will present you a rough insight of teaching information security in Austria.}, language = {en} } @misc{Frank2013, type = {Master Thesis}, author = {Frank, Mario}, title = {TEMPLAR : efficient determination of relevant axioms in big formula sets for theorem proving}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-72112}, school = {Universit{\"a}t Potsdam}, year = {2013}, abstract = {This document presents a formula selection system for classical first order theorem proving based on the relevance of formulae for the proof of a conjecture. It is based on unifiability of predicates and is also able to use a linguistic approach for the selection. The scope of the technique is the reduction of the set of formulae and the increase of the amount of provable conjectures in a given time. Since the technique generates a subset of the formula set, it can be used as a preprocessor for automated theorem proving. The document contains the conception, implementation and evaluation of both selection concepts. While the one concept generates a search graph over the negation normal forms or Skolem normal forms of the given formulae, the linguistic concept analyses the formulae and determines frequencies of lexemes and uses a tf-idf weighting algorithm to determine the relevance of the formulae. Though the concept is built for first order logic, it is not limited to it. The concept can be used for higher order and modal logik, too, with minimal adoptions. The system was also evaluated at the world championship of automated theorem provers (CADE ATP Systems Competition, CASC-24) in combination with the leanCoP theorem prover and the evaluation of the results of the CASC and the benchmarks with the problems of the CASC of the year 2012 (CASC-J6) show that the concept of the system has positive impact to the performance of automated theorem provers. Also, the benchmarks with two different theorem provers which use different calculi have shown that the selection is independent from the calculus. Moreover, the concept of TEMPLAR has shown to be competitive to some extent with the concept of SinE and even helped one of the theorem provers to solve problems that were not (or slower) solved with SinE selection in the CASC. Finally, the evaluation implies that the combination of the unification based and linguistic selection yields more improved results though no optimisation was done for the problems.}, language = {en} } @phdthesis{Huang2006, author = {Huang, Wanjun}, title = {Temporary binding for dynamic middleware construction and web services composition}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-7672}, school = {Universit{\"a}t Potsdam}, year = {2006}, abstract = {With increasing number of applications in Internet and mobile environments, distributed software systems are demanded to be more powerful and flexible, especially in terms of dynamism and security. This dissertation describes my work concerning three aspects: dynamic reconfiguration of component software, security control on middleware applications, and web services dynamic composition. Firstly, I proposed a technology named Routing Based Workflow (RBW) to model the execution and management of collaborative components and realize temporary binding for component instances. The temporary binding means component instances are temporarily loaded into a created execution environment to execute their functions, and then are released to their repository after executions. The temporary binding allows to create an idle execution environment for all collaborative components, on which the change operations can be immediately carried out. The changes on execution environment will result in a new collaboration of all involved components, and also greatly simplifies the classical issues arising from dynamic changes, such as consistency preserving etc. To demonstrate the feasibility of RBW, I created a dynamic secure middleware system - the Smart Data Server Version 3.0 (SDS3). In SDS3, an open source implementation of CORBA is adopted and modified as the communication infrastructure, and three secure components managed by RBW, are created to enhance the security on the access of deployed applications. SDS3 offers multi-level security control on its applications from strategy control to application-specific detail control. For the management by RBW, the strategy control of SDS3 applications could be dynamically changed by reorganizing the collaboration of the three secure components. In addition, I created the Dynamic Services Composer (DSC) based on Apache open source projects, Apache Axis and WSIF. In DSC, RBW is employed to model the interaction and collaboration of web services and to enable the dynamic changes on the flow structure of web services. Finally, overall performance tests were made to evaluate the efficiency of the developed RBW and SDS3. The results demonstrated that temporary binding of component instances makes slight impacts on the execution efficiency of components, and the blackout time arising from dynamic changes can be extremely reduced in any applications.}, subject = {Middleware}, language = {en} } @misc{HollmannFrohmeEndrullatetal.2020, author = {Hollmann, Susanne and Frohme, Marcus and Endrullat, Christoph and Kremer, Andreas and D'Elia, Domenica and Regierer, Babette and Nechyporenko, Alina}, title = {Ten simple rules on how to write a standard operating procedure}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {9}, issn = {1866-8372}, doi = {10.25932/publishup-52587}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-525877}, pages = {12}, year = {2020}, abstract = {Research publications and data nowadays should be publicly available on the internet and, theoretically, usable for everyone to develop further research, products, or services. The long-term accessibility of research data is, therefore, fundamental in the economy of the research production process. However, the availability of data is not sufficient by itself, but also their quality must be verifiable. Measures to ensure reuse and reproducibility need to include the entire research life cycle, from the experimental design to the generation of data, quality control, statistical analysis, interpretation, and validation of the results. Hence, high-quality records, particularly for providing a string of documents for the verifiable origin of data, are essential elements that can act as a certificate for potential users (customers). These records also improve the traceability and transparency of data and processes, therefore, improving the reliability of results. Standards for data acquisition, analysis, and documentation have been fostered in the last decade driven by grassroot initiatives of researchers and organizations such as the Research Data Alliance (RDA). Nevertheless, what is still largely missing in the life science academic research are agreed procedures for complex routine research workflows. Here, well-crafted documentation like standard operating procedures (SOPs) offer clear direction and instructions specifically designed to avoid deviations as an absolute necessity for reproducibility. Therefore, this paper provides a standardized workflow that explains step by step how to write an SOP to be used as a starting point for appropriate research documentation.}, language = {en} } @phdthesis{Lorenz2011, author = {Lorenz, Haik}, title = {Texturierung und Visualisierung virtueller 3D-Stadtmodelle}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-53879}, school = {Universit{\"a}t Potsdam}, year = {2011}, abstract = {Im Mittelpunkt dieser Arbeit stehen virtuelle 3D-Stadtmodelle, die Objekte, Ph{\"a}nomene und Prozesse in urbanen R{\"a}umen in digitaler Form repr{\"a}sentieren. Sie haben sich zu einem Kernthema von Geoinformationssystemen entwickelt und bilden einen zentralen Bestandteil geovirtueller 3D-Welten. Virtuelle 3D-Stadtmodelle finden nicht nur Verwendung als Mittel f{\"u}r Experten in Bereichen wie Stadtplanung, Funknetzplanung, oder L{\"a}rmanalyse, sondern auch f{\"u}r allgemeine Nutzer, die realit{\"a}tsnah dargestellte virtuelle St{\"a}dte in Bereichen wie B{\"u}rgerbeteiligung, Tourismus oder Unterhaltung nutzen und z. B. in Anwendungen wie GoogleEarth eine r{\"a}umliche Umgebung intuitiv erkunden und durch eigene 3D-Modelle oder zus{\"a}tzliche Informationen erweitern. Die Erzeugung und Darstellung virtueller 3D-Stadtmodelle besteht aus einer Vielzahl von Prozessschritten, von denen in der vorliegenden Arbeit zwei n{\"a}her betrachtet werden: Texturierung und Visualisierung. Im Bereich der Texturierung werden Konzepte und Verfahren zur automatischen Ableitung von Fototexturen aus georeferenzierten Schr{\"a}gluftbildern sowie zur Speicherung oberfl{\"a}chengebundener Daten in virtuellen 3D-Stadtmodellen entwickelt. Im Bereich der Visualisierung werden Konzepte und Verfahren f{\"u}r die multiperspektivische Darstellung sowie f{\"u}r die hochqualitative Darstellung nichtlinearer Projektionen virtueller 3D-Stadtmodelle in interaktiven Systemen vorgestellt. Die automatische Ableitung von Fototexturen aus georeferenzierten Schr{\"a}gluftbildern erm{\"o}glicht die Veredelung vorliegender virtueller 3D-Stadtmodelle. Schr{\"a}gluftbilder bieten sich zur Texturierung an, da sie einen Großteil der Oberfl{\"a}chen einer Stadt, insbesondere Geb{\"a}udefassaden, mit hoher Redundanz erfassen. Das Verfahren extrahiert aus dem verf{\"u}gbaren Bildmaterial alle Ansichten einer Oberfl{\"a}che und f{\"u}gt diese pixelpr{\"a}zise zu einer Textur zusammen. Durch Anwendung auf alle Oberfl{\"a}chen wird das virtuelle 3D-Stadtmodell fl{\"a}chendeckend texturiert. Der beschriebene Ansatz wurde am Beispiel des offiziellen Berliner 3D-Stadtmodells sowie der in GoogleEarth integrierten Innenstadt von M{\"u}nchen erprobt. Die Speicherung oberfl{\"a}chengebundener Daten, zu denen auch Texturen z{\"a}hlen, wurde im Kontext von CityGML, einem international standardisierten Datenmodell und Austauschformat f{\"u}r virtuelle 3D-Stadtmodelle, untersucht. Es wird ein Datenmodell auf Basis computergrafischer Konzepte entworfen und in den CityGML-Standard integriert. Dieses Datenmodell richtet sich dabei an praktischen Anwendungsf{\"a}llen aus und l{\"a}sst sich dom{\"a}nen{\"u}bergreifend verwenden. Die interaktive multiperspektivische Darstellung virtueller 3D-Stadtmodelle erg{\"a}nzt die gewohnte perspektivische Darstellung nahtlos um eine zweite Perspektive mit dem Ziel, den Informationsgehalt der Darstellung zu erh{\"o}hen. Diese Art der Darstellung ist durch die Panoramakarten von H. C. Berann inspiriert; Hauptproblem ist die {\"U}bertragung des multiperspektivischen Prinzips auf ein interaktives System. Die Arbeit stellt eine technische Umsetzung dieser Darstellung f{\"u}r 3D-Grafikhardware vor und demonstriert die Erweiterung von Vogel- und Fußg{\"a}ngerperspektive. Die hochqualitative Darstellung nichtlinearer Projektionen beschreibt deren Umsetzung auf 3D-Grafikhardware, wobei neben der Bildwiederholrate die Bildqualit{\"a}t das wesentliche Entwicklungskriterium ist. Insbesondere erlauben die beiden vorgestellten Verfahren, dynamische Geometrieverfeinerung und st{\"u}ckweise perspektivische Projektionen, die uneingeschr{\"a}nkte Nutzung aller hardwareseitig verf{\"u}gbaren, qualit{\"a}tssteigernden Funktionen wie z.~B. Bildraumgradienten oder anisotroper Texturfilterung. Beide Verfahren sind generisch und unterst{\"u}tzen verschiedene Projektionstypen. Sie erm{\"o}glichen die anpassungsfreie Verwendung g{\"a}ngiger computergrafischer Effekte wie Stilisierungsverfahren oder prozeduraler Texturen f{\"u}r nichtlineare Projektionen bei optimaler Bildqualit{\"a}t. Die vorliegende Arbeit beschreibt wesentliche Technologien f{\"u}r die Verarbeitung virtueller 3D-Stadtmodelle: Zum einen lassen sich mit den Ergebnissen der Arbeit Texturen f{\"u}r virtuelle 3D-Stadtmodelle automatisiert herstellen und als eigenst{\"a}ndige Attribute in das virtuelle 3D-Stadtmodell einf{\"u}gen. Somit tr{\"a}gt diese Arbeit dazu bei, die Herstellung und Fortf{\"u}hrung texturierter virtueller 3D-Stadtmodelle zu verbessern. Zum anderen zeigt die Arbeit Varianten und technische L{\"o}sungen f{\"u}r neuartige Projektionstypen f{\"u}r virtueller 3D-Stadtmodelle in interaktiven Visualisierungen. Solche nichtlinearen Projektionen stellen Schl{\"u}sselbausteine dar, um neuartige Benutzungsschnittstellen f{\"u}r und Interaktionsformen mit virtuellen 3D-Stadtmodellen zu erm{\"o}glichen, insbesondere f{\"u}r mobile Ger{\"a}te und immersive Umgebungen.}, language = {de} } @article{Saito2015, author = {Saito, Toshinori}, title = {The Key Competencies in Informatics and ICT viewed from Nussbaum's Ten Central Capabilities}, series = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, journal = {KEYCIT 2014 - Key Competencies in Informatics and ICT}, number = {7}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82718}, pages = {253 -- 266}, year = {2015}, abstract = {This article shows a discussion about the key competencies in informatics and ICT viewed from a philosophical foundation presented by Martha Nussbaum, which is known as 'ten central capabilities'. Firstly, the outline of 'The Capability Approach', which has been presented by Amartya Sen and Nussbaum as a theoretical framework of assessing the state of social welfare, will be explained. Secondly, the body of Nussbaum's ten central capabilities and the reason for being applied as the basis of discussion will be shown. Thirdly, the relationship between the concept of 'capability' and 'competency' is to be discussed. After that, the author's assumption of the key competencies in informatics and ICT led from the examination of Nussbaum's ten capabilities will be presented.}, language = {en} }