@inproceedings{97, abstract = {{Bridging the gap between informal, imprecise, and vague user requirements descriptions and precise formalized specifications is the main task of requirements engineering. Techniques such as interviews or story telling are used when requirements engineers try to identify a user's needs. The requirements specification process is typically done in a dialogue between users, domain experts, and requirements engineers. In our research, we aim at automating the specification of requirements. The idea is to distinguish between untrained users and trained users, and to exploit domain knowledge learned from previous runs of our system. We let untrained users provide unstructured natural language descriptions, while we allow trained users to provide examples of behavioral descriptions. In both cases, our goal is to synthesize formal requirements models similar to statecharts. From requirements specification processes with trained users, behavioral ontologies are learned which are later used to support the requirements specification process for untrained users. Our research method is original in combining natural language processing and search-based techniques for the synthesis of requirements specifications. Our work is embedded in a larger project that aims at automating the whole software development and deployment process in envisioned future software service markets.}}, author = {{van Rooijen, Lorijn and Bäumer, Frederik Simon and Platenius, Marie Christin and Geierhos, Michaela and Hamann, Heiko and Engels, Gregor}}, booktitle = {{2017 IEEE 25th International Requirements Engineering Conference Workshops (REW)}}, isbn = {{978-1-5386-3489-9}}, keywords = {{Software, Unified modeling language, Requirements engineering, Ontologies, Search problems, Natural languages}}, location = {{Lisbon, Portugal}}, pages = {{379--385}}, publisher = {{IEEE}}, title = {{{From User Demand to Software Service: Using Machine Learning to Automate the Requirements Specification Process}}}, doi = {{10.1109/REW.2017.26}}, year = {{2017}}, } @inproceedings{55, abstract = {{We introduce the mobile server problem, inspired by current trends to move computational tasks from cloud structures to multiple devices close to the end user. An example for this are embedded systems in autonomous cars that communicate in order to coordinate their actions. Our model is a variant of the classical Page Migration Problem. Moreformally, we consider a mobile server holding a data page.The server can move in the Euclidean space (of arbitrary dimension). In every round, requests for data items from the page pop up at arbitrary points in the space. The requests are served, each at a cost of the distance from the requesting point and the server, and the mobile server may move, at a cost D times the distance traveled for some constant D . We assume a maximum distance m the server is allowed to move per round. We show that no online algorithm can achieve a competitive ratio independent of the length of the input sequence in this setting. Hence we augment the maximum movement distance of the online algorithms to ( 1 + δ) times the maximum distance of the offline solution. We provide a deterministic algorithm which is simple to describe and works for multiple variants of our problem. The algorithm achieves almost tight competitive ratios independent of the length of the input sequence.}}, author = {{Feldkord, Björn and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceedings of the 29th ACM Symposium on Parallelism in Algorithms and Architectures (SPAA)}}, pages = {{313--319}}, title = {{{The Mobile Server Problem}}}, doi = {{10.1145/3087556.3087575}}, year = {{2017}}, } @inproceedings{66, abstract = {{In budget games, players compete over resources with finite budgets. For every resource, a player has a specific demand and as a strategy, he chooses a subset of resources. If the total demand on a resource does not exceed its budget, the utility of each player who chose that resource equals his demand. Otherwise, the budget is shared proportionally. In the general case, pure Nash equilibria (NE) do not exist for such games. In this paper, we consider the natural classes of singleton and matroid budget games with additional constraints and show that for each, pure NE can be guaranteed. In addition, we introduce a lexicographical potential function to prove that every matroid budget game has an approximate pure NE which depends on the largest ratio between the different demands of each individual player.}}, author = {{Drees, Maximilian and Feldotto, Matthias and Riechers, Sören and Skopalik, Alexander}}, booktitle = {{Proceedings of the 23rd International Computing and Combinatorics Conference (COCOON)}}, pages = {{175----187}}, title = {{{Pure Nash Equilibria in Restricted Budget Games}}}, doi = {{10.1007/978-3-319-62389-4_15}}, year = {{2017}}, } @misc{695, author = {{Nowack, Joshua}}, publisher = {{Universität Paderborn}}, title = {{{On-The-Fly Konstruktion zusammenhängender Straßennetze aus gegebenen Einzelteilen}}}, year = {{2017}}, } @book{16444, author = {{Gausemeier, Jürgen and Bodden, Eric and Dressler, Falko and Dumitrescu, Roman and Meyer auf der Heide, Friedhelm and Scheytt, Christoph and Trächtler, Ansgar}}, pages = {{369}}, title = {{{Wissenschaftsforum Intelligente Technische Systeme (WInTeSys)}}}, year = {{2017}}, } @inbook{16461, author = {{Bemmann, Pascal and Biermeier, Felix and Bürmann, Jan and Kemper, Arne and Knollmann, Till and Knorr, Steffen and Kothe, Nils and Mäcker, Alexander and Malatyali, Manuel and Meyer auf der Heide, Friedhelm and Riechers, Sören and Schaefer, Johannes Sebastian and Sundermeier, Jannik}}, booktitle = {{Structural Information and Communication Complexity}}, isbn = {{9783319720494}}, issn = {{0302-9743}}, title = {{{Monitoring of Domain-Related Problems in Distributed Data Streams}}}, doi = {{10.1007/978-3-319-72050-0_13}}, year = {{2017}}, } @misc{1073, author = {{Nachtigall, Simon}}, publisher = {{Universität Paderborn}}, title = {{{Sortieren dynamischer Daten}}}, year = {{2017}}, } @misc{1074, author = {{Pukrop, Simon}}, publisher = {{Universität Paderborn}}, title = {{{Robuste Optimierung in Congestion Games}}}, year = {{2017}}, } @misc{1080, author = {{Bürmann, Jan}}, publisher = {{Universität Paderborn}}, title = {{{Complexity of Signalling in Routing Games under Uncertainty}}}, year = {{2017}}, } @misc{1081, author = {{Vijayalakshmi, Vipin Ravindran}}, publisher = {{Universität Paderborn}}, title = {{{Bounding the Inefficiency of Equilibria in Congestion Games under Taxation}}}, year = {{2017}}, } @inproceedings{1094, abstract = {{Many university students struggle with motivational problems, and gamification has the potential to address these problems. However, gamification is hardly used in education, because current approaches to gamification require instructors to engage in the time-consuming preparation of their course contents for use in quizzes, mini-games and the like. Drawing on research on limited attention and present bias, we propose a "lean" approach to gamification, which relies on gamifying learning activities (rather than learning contents) and increasing their salience. In this paper, we present the app StudyNow that implements such a lean gamification approach. With this app, we aim to enable more students and instructors to benefit from the advantages of gamification.}}, author = {{Feldotto, Matthias and John, Thomas and Kundisch, Dennis and Hemsen, Paul and Klingsieck, Katrin and Skopalik, Alexander}}, booktitle = {{Proceedings of the 12th International Conference on Design Science Research in Information Systems and Technology (DESRIST)}}, pages = {{462--467}}, title = {{{Making Gamification Easy for the Professor: Decoupling Game and Content with the StudyNow Mobile App}}}, doi = {{10.1007/978-3-319-59144-5_32}}, year = {{2017}}, } @inproceedings{1095, abstract = {{Many university students struggle with motivational problems, and gamification has the potential to address these problems. However, using gamification currently is rather tedious and time-consuming for instructors because current approaches to gamification require instructors to engage in the time-consuming preparation of course contents (e.g., for quizzes or mini-games). In reply to this issue, we propose a “lean” approach to gamification, which relies on gamifying learning activities rather than learning contents. The learning activities that are gamified in the lean approach can typically be drawn from existing course syllabi (e.g., attend certain lectures, hand in assignments, read book chapters and articles). Hence, compared to existing approaches, lean gamification substantially lowers the time requirements posed on instructors for gamifying a given course. Drawing on research on limited attention and the present bias, we provide the theoretical foundation for the lean gamification approach. In addition, we present a mobile application that implements lean gamification and outline a mixed-methods study that is currently under way for evaluating whether lean gamification does indeed have the potential to increase students’ motivation. We thereby hope to allow more students and instructors to benefit from the advantages of gamification. }}, author = {{John, Thomas and Feldotto, Matthias and Hemsen, Paul and Klingsieck, Katrin and Kundisch, Dennis and Langendorf, Mike}}, booktitle = {{Proceedings of the 25th European Conference on Information Systems (ECIS)}}, pages = {{2970--2979}}, title = {{{Towards a Lean Approach for Gamifying Education}}}, year = {{2017}}, } @article{110, abstract = {{We consider an extension of the dynamic speed scaling scheduling model introduced by Yao et al.: A set of jobs, each with a release time, deadline, and workload, has to be scheduled on a single, speed-scalable processor. Both the maximum allowed speed of the processor and the energy costs may vary continuously over time. The objective is to find a feasible schedule that minimizes the total energy costs. Theoretical algorithm design for speed scaling problems often tends to discretize problems, as our tools in the discrete realm are often better developed or understood. Using the above speed scaling variant with variable, continuous maximal processor speeds and energy prices as an example, we demonstrate that a more direct approach via tools from variational calculus can not only lead to a very concise and elegant formulation and analysis, but also avoids the “explosion of variables/constraints” that often comes with discretizing. Using well-known tools from calculus of variations, we derive combinatorial optimality characteristics for our continuous problem and provide a quite concise and simple correctness proof.}}, author = {{Antoniadis, Antonios and Kling, Peter and Ott, Sebastian and Riechers, Sören}}, journal = {{Theoretical Computer Science}}, pages = {{1--13}}, publisher = {{Elsevier}}, title = {{{Continuous Speed Scaling with Variability: A Simple and Direct Approach}}}, doi = {{10.1016/j.tcs.2017.03.021}}, year = {{2017}}, } @inproceedings{16338, abstract = {{To detect errors or find potential for improvement during the CAD-supported development of a complex technical system like modern industrial machines, the system’s virtual prototype can be examined in virtual reality (VR) in the context of virtual design reviews. Besides exploring the static shape of the examined system, observing the machines’ mechanics (e.g., motor-driven mechanisms) and transport routes for the material transport (e.g., via conveyor belts or chains, or rail-based transport systems) can play an equally important role in such a review. In practice it is often the case, that the relevant information about transport routes, or kinematic properties is either not consequently modeled in the CAD data or is lost during conversion processes. To significantly reduce the manual effort and costs for creating animations of the machines complex behavior with such limited input data for a design review, we present a set of algorithms to automatically determine geometrical properties of machine parts based only on their triangulated surfaces. The algorithms allow to detect the course of transport systems, the orientation of objects in 3d space, rotation axes of cylindrical objects and holes, the number of tooth of gears, as well as the tooth spacing of toothed racks. We implemented the algorithms in the VR system PADrend and applied them to animate virtual prototypes of real machines.}}, author = {{Brandt, Sascha and Fischer, Matthias and Gerges, Maria and Jähn, Claudius and Berssenbrügge, Jan}}, booktitle = {{Volume 1: 37th Computers and Information in Engineering Conference}}, isbn = {{9780791858110}}, location = {{Cleveland, USA}}, pages = {{91:1--91:10}}, title = {{{Automatic Derivation of Geometric Properties of Components From 3D Polygon Models}}}, doi = {{10.1115/detc2017-67528}}, volume = {{1}}, year = {{2017}}, } @inproceedings{16339, abstract = {{In der CAD-unterstützten Entwicklung von technischen Systemen (Maschinen, Anlagen etc.) werden virtuelle Prototypen im Rahmen eines virtuellen Design-Reviews mit Hilfe eines VR-Systems gesamtheitlich betrachtet, um frühzeitig Fehler und Verbesserungsbedarf zu erkennen. Ein wichtiger Untersuchungsgegenstand ist dabei die Analyse von Transportwegen für den Materialtransport mittels Fließbändern, Förderketten oder schienenbasierten Transportsystemen. Diese Transportwege werden im VR-System animiert. Problematisch dabei ist, dass derartige Transportsysteme im zugrundeliegenden CAD-Modell in der Praxis oft nicht modelliert und nur exemplarisch angedeutet werden, da diese für die Konstruktion nicht relevant sind (z.B. der Fördergurt eines Förderbandes, oder die Kette einer Förderkette), oder die Informationen über den Verlauf bei der Konvertierung der Daten in das VR-System verloren gehen. Bei der Animation dieser Transportsysteme in einem VR-System muss der Transportweg also aufwändig, manuell nachgearbeitet werden. Das Ziel dieser Arbeit ist die Reduzierung des notwendigen manuellen Nachbearbeitungsaufwandes für das Design-Review durch eine automatische Berechnung der Animationspfade entlang eines Transportsystems. Es wird ein Algorithmus vorgestellt, der es ermöglicht mit nur geringem zeitlichem Benutzeraufwand den Animationspfad aus den reinen polygonalen dreidimensionalen Daten eines Transportsystems automatisch zu rekonstruieren.}}, author = {{Brandt, Sascha and Fischer, Matthias}}, booktitle = {{Wissenschaftsforum Intelligente Technische Systeme (WInTeSys) 2017}}, location = {{Paderborn}}, pages = {{415--427}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Automatische Ableitung der Transportwege von Transportsystemen aus dem 3D-Polygonmodell}}}, volume = {{369}}, year = {{2017}}, } @inproceedings{16347, author = {{Fischer, Matthias and Jung, Daniel and Meyer auf der Heide, Friedhelm}}, booktitle = {{Algorithms for Sensor Systems - 13th International Symposium on Algorithms and Experiments for Wireless Sensor Networks, {ALGOSENSORS}}}, editor = {{Fernández Anta, Antonio and Jurdzinski, Tomasz and Mosteiro, Miguel A. and Zhang, Yanyong}}, pages = {{168--181}}, publisher = {{Springer}}, title = {{{Gathering Anonymous, Oblivious Robots on a Grid}}}, doi = {{10.1007/978-3-319-72751-6_13}}, volume = {{10718}}, year = {{2017}}, } @inproceedings{16348, author = {{Biermeier, Felix and Feldkord, Björn and Malatyali, Manuel and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceedings of the 15th Workshop on Approximation and Online Algorithms (WAOA)}}, pages = {{285 -- 300}}, publisher = {{Springer}}, title = {{{A Communication-Efficient Distributed Data Structure for Top-k and k-Select Queries}}}, doi = {{10.1007/978-3-319-89441-6_21}}, year = {{2017}}, } @inproceedings{16349, author = {{Podlipyan, Pavel and Li, Shouwei and Markarian, Christine and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceedings of the 13th International Symposium on Algorithms and Experiments for Wireless Networks (ALGOSENSORS)}}, pages = {{182--197}}, title = {{{A Continuous Strategy for Collisionless Gathering}}}, doi = {{10.1007/978-3-319-72751-6_14 }}, year = {{2017}}, } @inproceedings{19961, abstract = {{The self-organizing bio-hybrid collaboration ofrobots and natural plants allows for a variety of interestingapplications. As an example we investigate how robots can beused to control the growth and motion of a natural plant, using LEDs to provide stimuli. We follow an evolutionaryrobotics approach where task performance is determined bymonitoring the plant's reaction. First, we do initial plantexperiments with simple, predetermined controllers. Then weuse image sampling data as a model of the dynamics ofthe plant tip xy position. Second, we use this approach toevolve robot controllers in simulation. The task is to makethe plant approach three predetermined, distinct points in anxy-plane. Finally, we test the evolved controllers in real plantexperiments and find that we cross the reality gap successfully. We shortly describe how we have extended from plant tipto many points on the plant, for a model of the plant stemdynamics. Future work will extend to two-axes image samplingfor a 3-d approach.}}, author = {{Wahby, Mostafa and Hofstadler, Daniel Nicolas and Heinrich, Mary Katherine and Zahadat, Payam and Hamann, Heiko}}, booktitle = {{Proc. of the 10th International Conference on Self-Adaptive and Self-Organizing Systems}}, isbn = {{9781509035342}}, title = {{{An Evolutionary Robotics Approach to the Control of Plant Growth and Motion: Modeling Plants and Crossing the Reality Gap}}}, doi = {{10.1109/saso.2016.8}}, year = {{2016}}, } @inproceedings{19968, author = {{Heinrich, Mary Katherine and Wahby, Mostafa and Divband Soorati, Mohammad and Hofstadler, Daniel Nicolas and Zahadat, Payam and Ayres, Phil and Stoy, Kasper and Hamann, Heiko}}, booktitle = {{Proc. of the 1st International Workshop on Self-Organising Construction (SOCO)}}, isbn = {{9781509036516}}, title = {{{Self-Organized Construction with Continuous Building Material: Higher Flexibility Based on Braided Structures}}}, doi = {{10.1109/fas-w.2016.43}}, year = {{2016}}, } @article{19969, author = {{Hamann, Heiko and Khaluf, Yara and Botev, Jean and Divband Soorati, Mohammad and Ferrante, Eliseo and Kosak, Oliver and Montanier, Jean-Marc and Mostaghim, Sanaz and Redpath, Richard and Timmis, Jon and Veenstra, Frank and Wahby, Mostafa and Zamuda, Aleš}}, issn = {{2296-9144}}, journal = {{Frontiers in Robotics and AI}}, title = {{{Hybrid Societies: Challenges and Perspectives in the Design of Collective Behavior in Self-organizing Systems}}}, doi = {{10.3389/frobt.2016.00014}}, year = {{2016}}, } @inproceedings{19979, author = {{Hamann, Heiko and Divband Soorati, Mohammad}}, booktitle = {{IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2016)}}, title = {{{Robot Self-Assembly as Adaptive Growth Process: Collective Selection of Seed Position and Self-Organizing Tree-Structures}}}, doi = {{10.1109/IROS.2016.7759845}}, year = {{2016}}, } @article{19983, author = {{Dorigo, Marco and Hamann, Heiko and Valentini, Gabriele and Ferrante, Eliseo}}, journal = {{Journal of Autonomous Agents and Multi-Agent Systems}}, number = {{3}}, pages = {{553--580}}, title = {{{Collective Decision with 100 Kilobots: Speed vs Accuracy in Binary Discrimination Problems}}}, doi = {{10.1007/s10458-015-9323-3}}, volume = {{30}}, year = {{2016}}, } @phdthesis{200, author = {{Drees, Maximilian}}, publisher = {{Universität Paderborn}}, title = {{{Existence and Properties of Pure Nash Equilibria in Budget Games}}}, year = {{2016}}, } @inproceedings{20000, author = {{Hamann, Heiko and Valentini, Gabriele and Dorigo, Marco}}, booktitle = {{10th Int. Conf. on Swarm Intelligence, ANTS 2016}}, isbn = {{9783319444260}}, issn = {{0302-9743}}, title = {{{Population Coding: A New Design Paradigm for Embodied Distributed Systems}}}, doi = {{10.1007/978-3-319-44427-7_15}}, year = {{2016}}, } @inproceedings{20001, author = {{von Mammen, Sebastian and Hamann, Heiko and Heider, Michael}}, booktitle = {{ACM Symposium on Virtual Reality Software and Technology (VRST)}}, isbn = {{9781450344913}}, title = {{{Robot Gardens: An Augmented Reality Prototype for Plant-Robot Biohybrid Systems}}}, doi = {{10.1145/2993369.2993400}}, year = {{2016}}, } @inproceedings{20002, author = {{Rybář, Milan and Hamann, Heiko}}, booktitle = {{Proceedings of the Genetic and Evolutionary Computation Conference (GECCO 2016)}}, isbn = {{9781450342063}}, title = {{{Inspiration-Triggered Search: Towards Higher Complexities by Mimicking Creative Processes}}}, doi = {{10.1145/2908812.2908815}}, year = {{2016}}, } @inproceedings{20003, author = {{Khaluf, Yara and Hamann, Heiko}}, booktitle = {{ANTS 2016}}, pages = {{298}}, title = {{{On the Definition of Self-organizing Systems: Relevance of Positive/Negative Feedback and Fluctuations}}}, volume = {{9882}}, year = {{2016}}, } @inproceedings{20004, author = {{Valentini, Gabriele and Brambilla, Davide and Hamann, Heiko and Dorigo, Marco}}, booktitle = {{10th Int. Conf. on Swarm Intelligence, ANTS 2016}}, isbn = {{9783319444260}}, issn = {{0302-9743}}, title = {{{Collective Perception of Environmental Features in a Robot Swarm}}}, doi = {{10.1007/978-3-319-44427-7_6}}, year = {{2016}}, } @misc{210, author = {{Leder, Lennart}}, publisher = {{Universität Paderborn}}, title = {{{Congestion Games with Mixed Objectives}}}, year = {{2016}}, } @inproceedings{215, abstract = {{We present three robust overlay networks: First, we present a network that organizes the nodes into an expander and is resistant to even massive adversarial churn. Second, we develop a network based on the hypercube that maintains connectivity under adversarial DoS-attacks. For the DoS-attacks we use the notion of a Omega(log log n)-late adversary which only has access to topological information that is at least Omega(log log n) rounds old. Finally, we develop a network that combines both churn- and DoS-resistance. The networks gain their robustness through constant network reconfiguration, i.e., the topology of the networks changes constantly. Our reconguration algorithms are based on node sampling primitives for expanders and hypercubes that allow each node to sample a logarithmic number of nodes uniformly at random in O(log log n) communication rounds. These primitives are specific to overlay networks and their optimal runtime represents an exponential improvement over known techniques. Our results have a wide range of applications, for example in the area of scalable and robust peer-to-peer systems.}}, author = {{Drees, Maximilian and Gmyr, Robert and Scheideler, Christian}}, booktitle = {{Proceedings of the 28th ACM Symposium on Parallelism in Algorithms and Architectures (SPAA)}}, pages = {{417----427}}, title = {{{Churn- and DoS-resistant Overlay Networks Based on Network Reconfiguration}}}, doi = {{10.1145/2935764.2935783}}, year = {{2016}}, } @inproceedings{17655, author = {{Polevoy, Gleb and de Weerdt, M.M. and Jonker, C.M.}}, booktitle = {{Proceedings of the 2016 European Conference on Artificial Intelligence}}, keywords = {{agents, action, repeated reciprocation, fixed, floating, network, Nash equilibrium, social welfare, price of anarchy, price of stability, convex combination}}, pages = {{417--425}}, title = {{{The Game of Reciprocation Habits}}}, doi = {{10.3233/978-1-61499-672-9-417}}, volume = {{Volume 285: ECAI 2016}}, year = {{2016}}, } @inproceedings{17656, author = {{Polevoy, Gleb and de Weerdt, Mathijs and Jonker, Catholijn}}, booktitle = {{Proceedings of the 2016 International Conference on Autonomous Agents and Multiagent Systems}}, isbn = {{978-1-4503-4239-1}}, keywords = {{agent's influence, behavior, convergence, perron-frobenius, reciprocal interaction, repeated reciprocation}}, pages = {{1431--1432}}, publisher = {{International Foundation for Autonomous Agents and Multiagent Systems}}, title = {{{The Convergence of Reciprocation}}}, year = {{2016}}, } @inproceedings{177, abstract = {{Efficiently parallelizable parameterized problems have been classified as being either in the class FPP (fixed-parameter parallelizable) or the class PNC (parameterized analog of NC), which contains FPP as a subclass. In this paper, we propose a more restrictive class of parallelizable parameterized problems called fixed-parameter parallel-tractable (FPPT). For a problem to be in FPPT, it should possess an efficient parallel algorithm not only from a theoretical standpoint but in practice as well. The primary distinction between FPPT and FPP is the parallel processor utilization, which is bounded by a polynomial function in the case of FPPT. We initiate the study of FPPT with the well-known k-vertex cover problem. In particular, we present a parallel algorithm that outperforms the best known parallel algorithm for this problem: using O(m) instead of O(n2) parallel processors, the running time improves from 4logn+O(kk) to O(k⋅log3n), where m is the number of edges, n is the number of vertices of the input graph, and k is an upper bound of the size of the sought vertex cover. We also note that a few P-complete problems fall into FPPT including the monotone circuit value problem (MCV) when the underlying graphs are bounded by a constant Euler genus.}}, author = {{Abu-Khzam, Faisal N. and Li, Shouwei and Markarian, Christine and Meyer auf der Heide, Friedhelm and Podlipyan, Pavel}}, booktitle = {{Proceedings of the 10th International Conference on Combinatorial Optimization and Applications (COCOA)}}, pages = {{477--488}}, title = {{{On the Parameterized Parallel Complexity and the Vertex Cover Problem}}}, doi = {{10.1007/978-3-319-48749-6_35}}, year = {{2016}}, } @misc{187, booktitle = {{Transactions on Parallel Computing (TOPC)}}, editor = {{Meyer auf der Heide, Friedhelm}}, number = {{1}}, pages = {{1}}, title = {{{Introduction to the Special Issue on SPAA 2014}}}, doi = {{10.1145/2936716}}, year = {{2016}}, } @inproceedings{207, abstract = {{We consider a scheduling problem where machines need to be rented from the cloud in order to process jobs. There are two types of machines available which can be rented for machine-type dependent prices and for arbitrary durations. However, a machine-type dependent setup time is required before a machine is available for processing. Jobs arrive online over time, have machine-type dependent sizes and have individual deadlines. The objective is to rent machines and schedule jobs so as to meet all deadlines while minimizing the rental cost. Since we observe the slack of jobs to have a fundamental influence on the competitiveness, we study the model when instances are parameterized by their (minimum) slack. An instance is called to have a slack of $\beta$ if, for all jobs, the difference between the job's release time and the latest point in time at which it needs to be started is at least $\beta$. While for $\beta series = {LNCS}}}, author = {{Mäcker, Alexander and Malatyali, Manuel and Meyer auf der Heide, Friedhelm and Riechers, Sören}}, booktitle = {{Proceedings of the 10th Annual International Conference on Combinatorial Optimization and Applications (COCOA)}}, pages = {{578----592}}, title = {{{Cost-efficient Scheduling on Machines from the Cloud}}}, doi = {{10.1007/978-3-319-48749-6_42}}, year = {{2016}}, } @inproceedings{209, abstract = {{We study a new class of games which generalizes congestion games and its bottleneck variant. We introduce congestion games with mixed objectives to model network scenarios in which players seek to optimize for latency and bandwidths alike. We characterize the existence of pure Nash equilibria (PNE) and the convergence of improvement dynamics. For games that do not possess PNE we give bounds on the approximation ratio of approximate pure Nash equilibria.}}, author = {{Feldotto, Matthias and Leder, Lennart and Skopalik, Alexander}}, booktitle = {{Proceedings of the 10th Annual International Conference on Combinatorial Optimization and Applications (COCOA)}}, pages = {{655----669}}, title = {{{Congestion Games with Mixed Objectives}}}, doi = {{10.1007/978-3-319-48749-6_47}}, year = {{2016}}, } @misc{5406, author = {{Bülling, Jonas}}, title = {{{Parallelisierung von Algorithmen zur IR-Luftbildanalyse von Laubholzmischbeständen zur Verifizierung der Ausbreitung von Eichenkomplexschäden}}}, year = {{2016}}, } @misc{5407, author = {{Koepe, Jörn}}, publisher = {{Universität Paderborn}}, title = {{{Price-Based Allocation Games}}}, year = {{2016}}, } @misc{688, author = {{Kutzias, Damian}}, publisher = {{Universität Paderborn}}, title = {{{Friendship Processes in Network Creation Games}}}, year = {{2016}}, } @misc{689, author = {{Schaefer, Johannes Sebastian}}, publisher = {{Universität Paderborn}}, title = {{{Routing Algorithms on Delayed Networks for Disaster Management Support}}}, year = {{2016}}, } @unpublished{16450, abstract = {{In this paper, we solve the local gathering problem of a swarm of $n$ indistinguishable, point-shaped robots on a two dimensional grid in asymptotically optimal time $\mathcal{O}(n)$ in the fully synchronous $\mathcal{FSYNC}$ time model. Given an arbitrarily distributed (yet connected) swarm of robots, the gathering problem on the grid is to locate all robots within a $2\times 2$-sized area that is not known beforehand. Two robots are connected if they are vertical or horizontal neighbors on the grid. The locality constraint means that no global control, no compass, no global communication and only local vision is available; hence, a robot can only see its grid neighbors up to a constant $L_1$-distance, which also limits its movements. A robot can move to one of its eight neighboring grid cells and if two or more robots move to the same location they are \emph{merged} to be only one robot. The locality constraint is the significant challenging issue here, since robot movements must not harm the (only globally checkable) swarm connectivity. For solving the gathering problem, we provide a synchronous algorithm -- executed by every robot -- which ensures that robots merge without breaking the swarm connectivity. In our model, robots can obtain a special state, which marks such a robot to be performing specific connectivity preserving movements in order to allow later merge operations of the swarm. Compared to the grid, for gathering in the Euclidean plane for the same robot and time model the best known upper bound is $\mathcal{O}(n^2)$.}}, author = {{Cord-Landwehr, Andreas and Fischer, Matthias and Jung, Daniel and Meyer auf der Heide, Friedhelm}}, booktitle = {{arXiv:1602.03303}}, title = {{{Asymptotically Optimal Gathering on a Grid}}}, year = {{2016}}, } @inproceedings{169, abstract = {{We apply methods of genetic programming to a general problem from software engineering, namely example-based generation of specifications. In particular, we focus on model transformation by example. The definition and implementation of model transformations is a task frequently carried out by domain experts, hence, a (semi-)automatic approach is desirable. This application is challenging because the underlying search space has rich semantics, is high-dimensional, and unstructured. Hence, a computationally brute-force approach would be unscalable and potentially infeasible. To address that problem, we develop a sophisticated approach of designing complex mutation operators. We define ‘patterns’ for constructing mutation operators and report a successful case study. Furthermore, the code of the evolved model transformation is required to have high maintainability and extensibility, that is, the code should be easily readable by domain experts. We report an evaluation of this approach in a software engineering case study.}}, author = {{Kühne, Thomas and Hamann, Heiko and Arifulina, Svetlana and Engels, Gregor}}, booktitle = {{Proceedings of the 19th European Conference on Genetic Programming (EuroGP 2016)}}, pages = {{278----293}}, title = {{{Patterns for Constructing Mutation Operators: Limiting the Search Space in a Software Engineering Application}}}, doi = {{10.1007/978-3-319-30668-1_18}}, year = {{2016}}, } @misc{1082, author = {{Handirk, Tobias}}, publisher = {{Universität Paderborn}}, title = {{{Über die Rolle von Informationen in Verkehrsnetzwerken}}}, year = {{2016}}, } @phdthesis{154, author = {{Cord-Landwehr, Andreas}}, isbn = {{978-3-942647-72-4}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts, Paderborn}}, title = {{{Selfish Network Creation - On Variants of Network Creation Games}}}, volume = {{353}}, year = {{2016}}, } @inproceedings{157, abstract = {{Consider a scheduling problem in which a set of jobs with interjob communication, canonically represented by a weighted tree, needs to be scheduled on m parallel processors interconnected by a shared communication channel. In each time step, we may allow any processed job to use a certain capacity of the channel in order to satisfy (parts of) its communication demands to adjacent jobs processed in parallel. The goal is to find a schedule that minimizes the makespan and in which communication demands of all jobs are satisfied.We show that this problem is NP-hard in the strong sense even if the number of processors and the maximum degree of the underlying tree is constant.Consequently, we design and analyze simple approximation algorithms with asymptotic approximation ratio 2-2/m in case of paths and a ratio of 5/2 in case of arbitrary trees.}}, author = {{König, Jürgen and Mäcker, Alexander and Meyer auf der Heide, Friedhelm and Riechers, Sören}}, booktitle = {{Proceedings of the 10th Annual International Conference on Combinatorial Optimization and Applications (COCOA)}}, pages = {{563----577}}, title = {{{Scheduling with Interjob Communication on Parallel Processors}}}, doi = {{10.1007/978-3-319-48749-6_41}}, year = {{2016}}, } @article{159, abstract = {{Abstract—Max-min fairness (MMF) is a widely known approachto a fair allocation of bandwidth to each of the usersin a network. This allocation can be computed by uniformlyraising the bandwidths of all users without violating capacityconstraints. We consider an extension of these allocations byraising the bandwidth with arbitrary and not necessarily uniformtime-depending velocities (allocation rates). These allocationsare used in a game-theoretic context for routing choices, whichwe formalize in progressive filling games (PFGs). We present avariety of results for equilibria in PFGs. We show that these gamespossess pure Nash and strong equilibria. While computation ingeneral is NP-hard, there are polynomial-time algorithms forprominent classes of Max-Min-Fair Games (MMFG), includingthe case when all users have the same source-destination pair.We characterize prices of anarchy and stability for pure Nashand strong equilibria in PFGs and MMFGs when players havedifferent or the same source-destination pairs. In addition, weshow that when a designer can adjust allocation rates, it is possibleto design games with optimal strong equilibria. Some initial resultson polynomial-time algorithms in this direction are also derived.}}, author = {{Harks, Tobias and Höfer, Martin and Schewior, Kevin and Skopalik, Alexander}}, journal = {{IEEE/ACM Transactions on Networking}}, number = {{4}}, pages = {{2553 -- 2562}}, publisher = {{IEEE}}, title = {{{Routing Games With Progressive Filling}}}, doi = {{10.1109/TNET.2015.2468571}}, year = {{2016}}, } @inproceedings{149, abstract = {{In this paper we consider a strategic variant of the online facility location problem. Given is a graph in which each node serves two roles: it is a strategic client stating requests as well as a potential location for a facility. In each time step one client states a request which induces private costs equal to the distance to the closest facility. Before serving, the clients may collectively decide to open new facilities, sharing the corresponding price. Instead of optimizing the global costs, each client acts selfishly. The prices of new facilities vary between nodes and also change over time, but are always bounded by some fixed value α. Both the requests as well as the facility prices are given by an online sequence and are not known in advance.We characterize the optimal strategies of the clients and analyze their overall performance in comparison to a centralized offline solution. If all players optimize their own competitiveness, the global performance of the system is O(√α⋅α) times worse than the offline optimum. A restriction to a natural subclass of strategies improves this result to O(α). We also show that for fixed facility costs, we can find strategies such that this bound further improves to O(√α).}}, author = {{Drees, Maximilian and Feldkord, Björn and Skopalik, Alexander}}, booktitle = {{Proceedings of the 10th Annual International Conference on Combinatorial Optimization and Applications (COCOA)}}, pages = {{593----607}}, title = {{{Strategic Online Facility Location}}}, doi = {{10.1007/978-3-319-48749-6_43}}, year = {{2016}}, } @proceedings{163, editor = {{Dressler, Falko and Meyer auf der Heide, Friedhelm}}, location = {{Paderborn, Germany}}, publisher = {{ACM}}, title = {{{Proceedings of the 17th ACM International Symposium on Mobile Ad Hoc Networking and Computing (MobiHoc)}}}, doi = {{10.1145/2942358}}, year = {{2016}}, } @inproceedings{16351, abstract = {{Defining, measuring, and comparing the quality and efficiency of rendering algorithms in computer graphics is a demanding challenge: quality measures are often application specific and efficiency is strongly influenced by properties of the rendered scene and the used hardware. We survey the currently employed evaluation methods for AQ1 the development process of rendering algorithms. Then, we present our PADrend framework, which supports systematic and flexible development, evaluation, adaptation, and comparison of rendering algorithms, and provides a comfortable and easy-to-use platform for developers of rendering algorithms. The system includes a new evaluation method to improve the objectivity of experimental evaluations of rendering algorithms. }}, author = {{Fischer, Matthias and Jähn, Claudius and Meyer auf der Heide, Friedhelm and Petring, Ralf}}, booktitle = {{Algorithm Engineering}}, editor = {{Kliemann, Lasse and Sanders, Peter}}, pages = {{226--244}}, publisher = {{Springer}}, title = {{{Algorithm Engineering Aspects of Real-Time Rendering Algorithms}}}, doi = {{10.1007/978-3-319-49487-6_7 }}, volume = {{9220}}, year = {{2016}}, }