@inproceedings{28321, abstract = {{Der Lebenszyklus von Produktionssystemen besteht nach Wiendahl et al. aus den drei Phasen Planung und Realisierung, Betrieb und Redistribution (Wiendahl et al. in Anlaufrobuste Produktionssysteme. Werkstattstechnik (wt) online, Jahrg. 92, Ausgabe 11/12, 2002, S. 650-655). Jede Phase enthält vielfältige Aufgaben die maßgeblich vom Fach- und Erfahrungswissen der Mitarbeiter abhängen. In der ersten Phase werden unter anderem die Fertigungsprozesse und -ressourcen festgelegt. Hierfür bedarf es genauer Kenntnisse über die zu fertigenden Bauteile, benötigten Prozesse und geeigneten Ressourcen selbst sowie deren Abhängigkeiten untereinander. In der Betriebsphase des Produktionssystems muss auf Maschinenausfälle oder Eilaufträge mit Um- bzw. Neuplanungen von Ressourcen reagiert werden. Das benötigte Wissen im Lebenszyklus von Produktionssystemen verteilt sich in der Regel auf verschiedene Personen und eine Vielzahl unterschiedlicher Dokumente; teilweise ist es auch nur implizit vorhanden. Demzufolge liegt es verteilt und unstrukturiert vor und eignet sich nicht für eine bedarfsgerechte Bereitstellung. Darüber hinaus fehlt eine Semantik, die das vorhandene Wissen in Beziehung setzt und durch automatisierte Schlussfolgerungen ergänzt. Hierfür bieten wissensbasierte Systeme (WBS) auf Basis von Ontologien einen vielversprechenden Lösungsansatz. Diese bieten eine Semantik und Inferenz zur Wissensmodellierung und ermöglichen den effizienten Zugriff auf das benötigte Wissen. Dies verspricht eine große Zeitersparnis bei den Aufgaben im Lebenszyklus von Produktionssystemen, auch im Hinblick auf die immer kürzer werdenden Produktlebenszyklen. Der Beitrag beschreibt den Aufbau von drei Ontologien für das Wissensmanagement im Rahmen verschiedener Aufgaben. Ferner werden die Vorteile durch den Einsatz von Ontologien praxisorientiert anhand eines Produktionssystems für eine Taschenlampe dargestellt.}}, author = {{Petersen, Marcus and Rehage, Gerald and Gausemeier, Jürgen and Bauer, Frank}}, booktitle = {{Wissenschafts- und Industrieforum 2015 Intelligente Technische Systeme - 10. Paderborner Workshop Entwurf mechatronischer Systeme, Nr. 343}}, editor = {{Gausemeier, Jürgen and Dumitrescu, Roman and Rammig, Franz-Josef and Schäfer, Wilhelm and Trächtler, Ansgar}}, isbn = {{978-3-942647-62-5}}, pages = {{189--209}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts}}, title = {{{Wissensaufbereitung und -bereitstellung durch Ontologien im Lebenszyklus von Produktionssystemen}}}, year = {{2015}}, } @inbook{28360, abstract = {{Dieser Beitrag untersucht den Einfluss der Aussprache auf die Selbstkonstruktion von Lernenden und deren Bereitschaft, sich auf die zu erlernende Sprache und Kultur einzulassen. Im Gegensatz zu traditionellen Forschungsansätzen wird die Aussprache dabei als subjektiv bedeutsame Dimension im Sprachlernprozess konzipiert, die die Wahrnehmungen der Lernenden gegenüber sich selbst, anderen Sprechenden und dem gesamten Lernkontext stark mitprägt. Die Untersuchungen basieren auf den Narrationen zweier kanadischer Germanistikstudierender, die zwei Semester an deutschen Universitäten verbrachten. Der Selbstfindungs- und Lernprozess beider Studierender im fremden Umfeld wird dabei wesentlich durch ihre Selbstwahrnehmungen gelenkt, welche wiederum stark um das Thema Aussprache kreisen. Obwohl sich beide Lernende sehr unterschiedlich als Sprechende des Deutschen konstruieren, fixieren sie sich darauf, wie sie meinen zu klingen und folglich wahrgenommen zu werden. Dabei erweist sich vor allem das Konstrukt des Native Speaker als zentraler Vergleichspunkt, an dem sich die Lernenden messen und der somit als Basis für die Wertung des Auslandsaufenthalts und des eigenen Lernerfolgs dient. Durch die Analyse subjektiver Lernertheorien entwirft dieser Beitrag einen gänzlich neuen Rahmen für die Betrachtung von Aussprache im Sprachlernprozess, der über die rein phonetische Dimension hinausgeht und den Fokus auf die sozialpsychologischen Funktionen von Aussprache lenkt.}}, author = {{Müller, Mareike and Schmenk, Barbara}}, booktitle = {{Konzepte aus der Sprachlehrforschung – Impulse für die Praxis: Festschrift für Karin Kleppin}}, editor = {{Böcker , Jessica and Stauch, Annette}}, isbn = {{ 9783631647189}}, pages = {{171--188}}, publisher = {{Peter Lang}}, title = {{{Der Klang meines Selbst: Aussprache und Selbstkonstruktion von Fremdsprachenlernenden}}}, year = {{2015}}, } @inproceedings{241, abstract = {{Distributed applications are commonly based on overlay networks interconnecting their sites so that they can exchange information. For these overlay networks to preserve their functionality, they should be able to recover from various problems like membership changes or faults. Various self-stabilizing overlay networks have already been proposed in recent years, which have the advantage of being able to recover from any illegal state, but none of these networks can give any guarantees on its functionality while the recovery process is going on. We initiate research on overlay networks that are not only self-stabilizing but that also ensure that searchability is maintained while the recovery process is going on, as long as there are no corrupted messages in the system. More precisely, once a search message from node u to another node v is successfully delivered, all future search messages from u to v succeed as well. We call this property monotonic searchability. We show that in general it is impossible to provide monotonic searchability if corrupted messages are present in the system, which justifies the restriction to system states without corrupted messages. Furthermore, we provide a self-stabilizing protocol for the line for which we can also show monotonic searchability. It turns out that even for the line it is non-trivial to achieve this property. Additionally, we extend our protocol to deal with node departures in terms of the Finite Departure Problem of Foreback et. al (SSS 2014). This makes our protocol even capable of handling node dynamics.}}, author = {{Scheideler, Christian and Setzer, Alexander and Strothmann, Thim Frederik}}, booktitle = {{Proceedings of the 19th International Conference on Principles of Distributed Systems (OPODIS)}}, title = {{{Towards Establishing Monotonic Searchability in Self-Stabilizing Data Structures}}}, doi = {{10.4230/LIPIcs.OPODIS.2015.24}}, year = {{2015}}, } @inproceedings{242, abstract = {{A fundamental problem for overlay networks is to safely exclude leaving nodes, i.e., the nodes requesting to leave the overlay network are excluded from it without affecting its connectivity. There are a number of studies for safe node exclusion if the overlay is in a well-defined state, but almost no formal results are known for the case in which the overlay network is in an arbitrary initial state, i.e., when looking for a self-stabilizing solution for excluding leaving nodes. We study this problem in two variants: the Finite Departure Problem (FDP) and the Finite Sleep Problem (FSP). In the FDP the leaving nodes have to irrevocably decide when it is safe to leave the network, whereas in the FSP, this leaving decision does not have to be final: the nodes may resume computation when woken up by an incoming message. We are the first to present a self-stabilizing protocol for the FDP and the FSP that can be combined with a large class of overlay maintenance protocols so that these are then guaranteed to safely exclude leaving nodes from the system from any initial state while operating as specified for the staying nodes. In order to formally define the properties these overlay maintenance protocols have to satisfy, we identify four basic primitives for manipulating edges in an overlay network that might be of independent interest.}}, author = {{Koutsopoulos, Andreas and Scheideler, Christian and Strothmann, Thim Frederik}}, booktitle = {{Proceedings of the 17th International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS)}}, pages = {{201--216}}, title = {{{Towards a Universal Approach for the Finite Departure Problem in Overlay Networks}}}, doi = {{10.1007/978-3-319-21741-3_14}}, year = {{2015}}, } @inproceedings{243, abstract = {{This paper introduces the problem of communication pattern adaption for a distributed self-adjusting binary search tree. We propose a simple local algorithm, which is closely related to the nearly thirty-year-old idea of splay trees and evaluate its adaption performance in the distributed scenario if different communication patterns are provided.To do so, the process of self-adjustment is modeled similarly to a basic network creation game, in which the nodes want to communicate with only a certain subset of all nodes. We show that, in general, the game (i.e., the process of local adjustments) does not converge, and convergence is related to certain structures of the communication interests, which we call conflicts.We classify conflicts and show that for two communication scenarios in which convergence is guaranteed, the self-adjusting tree performs well.Furthermore, we investigate the different classes of conflicts separately and show that, for a certain class of conflicts, the performance of the tree network is asymptotically as good as the performance for converging instances. However, for the other conflict classes, a distributed self-adjusting binary search tree adapts poorly.}}, author = {{Strothmann, Thim Frederik}}, booktitle = {{Proceedings of the 9th International Workshop on Algorithms and Computation (WALCOM)}}, pages = {{175----186}}, title = {{{The impact of communication patterns on distributed locally self-adjusting binary search trees}}}, doi = {{10.1007/978-3-319-15612-5_16}}, year = {{2015}}, } @inproceedings{26434, author = {{Unger, Christina and Forascu, Corina and López, Vanessa and Ngonga Ngomo, Axel-Cyrille and Cabrio, Elena and Cimiano, Philipp and Walter, Sebastian}}, booktitle = {{Working Notes of {CLEF} 2015 - Conference and Labs of the Evaluation forum, Toulouse, France, September 8-11, 2015}}, editor = {{Cappellato, Linda and Ferro, Nicola and J. F. Jones, Gareth and SanJuan, Eric}}, publisher = {{CEUR-WS.org}}, title = {{{Question Answering over Linked Data (QALD-5)}}}, volume = {{1391}}, year = {{2015}}, } @inproceedings{266, abstract = {{Many markets have seen a shift from the idea of buying and moved to leasing instead. Arguably, the latter has been the major catalyst for their success. Ten years ago, research realized this shift and initiated the study of "online leasing problems" by introducing leasing to online optimization problems. Resources required to provide a service in an "online leasing problem" are no more bought but leased for different durations. In this paper, we provide an overview of results that contribute to the understanding of "online resource leasing problems". }}, author = {{Markarian, Christine and Meyer auf der Heide, Friedhelm}}, booktitle = {{Proceedings of the 2015 ACM Symposium on Principles of Distributed Computing (PODC)}}, pages = {{343--344}}, title = {{{Online Resource Leasing}}}, doi = {{10.1145/2767386.2767454}}, year = {{2015}}, } @article{26921, abstract = {{AbstractThe growth hormone (GH) insulin-like growth factor (IGF) axis has been linked to insulin metabolism and cancer risk. Experimental evidence indicates that the GH–IGF axis itself can be influenced by dietary flavonoids. As fruit and vegetable (FV) intake is a major source of flavonoid consumption, FV’s beneficial health effects may be explained via flavonoids’ influence on the GH–IGF axis, but observational evidence is currently rare. We used data from Dortmund Nutritional and Anthropometric Longitudinally Designed Study participants to analyse prospective associations between FV, fruit intake and flavonoid intake from FV (FlavFV) with IGF-1 and its binding proteins IGFBP-2 and IGFBP-3. Subjects needed to provide a fasting blood sample in adulthood (18–39 years) and at least two 3-d weighed dietary records in early life (0·5−2 years,n191), mid-childhood (3−7 years,n265) or adolescence (girls: 9−15 years, boys: 10−16 years,n261). Additional analyses were conducted among those providing at least three 24-h urine samples in adolescence (n236) to address the predictor urinary hippuric acid (HA), a biomarker of polyphenol intake. Higher fruit intake in mid-childhood and adolescence was related to higher IGFBP-2 in adulthood (P=0·03 andP=0·045). Comparable trends (P=0·045−0·09) were discernable for FV intake (but not FlavFV) in all three time windows. Similarly, higher adolescent HA excretion tended to be related (P=0·06) to higher adult IGFBP-2 levels. Regarding IGFBP-3, a marginal (P=0·08) positive association was observed with FlavFV in mid-childhood only. None of the investigated dietary factors was related to IGF-1. In conclusion, higher fruit and FV intakes during growth may be relevant for adult IGFBP-2, but probably not for IGFBP-3 or IGF-1.}}, author = {{Krupp, Danika and Remer, Thomas and Penczynski, Katharina J. and Bolzenius, Katja and Wudy, Stefan A. and Buyken, Anette}}, issn = {{0007-1145}}, journal = {{British Journal of Nutrition}}, pages = {{527--537}}, title = {{{Relevance of fruits, vegetables and flavonoids from fruits and vegetables during early life, mid-childhood and adolescence for levels of insulin-like growth factor (IGF-1) and its binding proteins IGFBP-2 and IGFBP-3 in young adulthood}}}, doi = {{10.1017/s0007114515004742}}, year = {{2015}}, } @article{320, abstract = {{We consider structural and algorithmic questions related to the Nash dynamics of weighted congestion games. In weighted congestion games with linear latency functions, the existence of pure Nash equilibria is guaranteed by a potential function argument. Unfortunately, this proof of existence is inefficient and computing pure Nash equilibria in such games is a PLS-hard problem even when all players have unit weights. The situation gets worse when superlinear (e.g., quadratic) latency functions come into play; in this case, the Nash dynamics of the game may contain cycles and pure Nash equilibria may not even exist. Given these obstacles, we consider approximate pure Nash equilibria as alternative solution concepts. A ρ--approximate pure Nash equilibrium is a state of a (weighted congestion) game from which no player has any incentive to deviate in order to improve her cost by a multiplicative factor higher than ρ. Do such equilibria exist for small values of ρ? And if so, can we compute them efficiently?We provide positive answers to both questions for weighted congestion games with polynomial latency functions by exploiting an “approximation” of such games by a new class of potential games that we call Ψ-games. This allows us to show that these games have d!-approximate pure Nash equilibria, where d is the maximum degree of the latency functions. Our main technical contribution is an efficient algorithm for computing O(1)-approximate pure Nash equilibria when d is a constant. For games with linear latency functions, the approximation guarantee is 3+√5/2 + Oγ for arbitrarily small γ > 0; for latency functions with maximum degree d≥ 2, it is d2d+o(d). The running time is polynomial in the number of bits in the representation of the game and 1/γ. As a byproduct of our techniques, we also show the following interesting structural statement for weighted congestion games with polynomial latency functions of maximum degree d ≥ 2: polynomially-long sequences of best-response moves from any initial state to a dO(d2)-approximate pure Nash equilibrium exist and can be efficiently identified in such games as long as d is a constant.To the best of our knowledge, these are the first positive algorithmic results for approximate pure Nash equilibria in weighted congestion games. Our techniques significantly extend our recent work on unweighted congestion games through the use of Ψ-games. The concept of approximating nonpotential games by potential ones is interesting in itself and might have further applications.}}, author = {{Caragiannis, Ioannis and Fanelli, Angelo and Gravin, Nick and Skopalik, Alexander}}, journal = {{Transactions on Economics and Computation}}, number = {{1}}, publisher = {{ACM}}, title = {{{Approximate Pure Nash Equilibria in Weighted Congestion Games: Existence, Efficient Computation, and Structure}}}, doi = {{10.1145/2614687}}, volume = {{3}}, year = {{2015}}, } @article{327, abstract = {{We consider the problem of resource discovery in distributed systems. In particular we give an algorithm, such that each node in a network discovers the address of any other node in the network. We model the knowledge of the nodes as a virtual overlay network given by a directed graph such that complete knowledge of all nodes corresponds to a complete graph in the overlay network. Although there are several solutions for resource discovery, our solution is the first that achieves worst-case optimal work for each node, i.e. the number of addresses (O(n)O(n)) or bits (O(nlog⁡n)O(nlog⁡n)) a node receives or sends coincides with the lower bound, while ensuring only a linear runtime (O(n)O(n)) on the number of rounds.}}, author = {{Kniesburges, Sebastian and Koutsopoulos, Andreas and Scheideler, Christian}}, journal = {{Theoretical Computer Science}}, pages = {{67--79}}, publisher = {{Elsevier}}, title = {{{A deterministic worst-case message complexity optimal solution for resource discovery}}}, doi = {{10.1016/j.tcs.2014.11.027}}, year = {{2015}}, } @inbook{293, abstract = {{Opinion mining from physician rating websites depends on the quality of the extracted information. Sometimes reviews are user-error prone and the assigned stars or grades contradict the associated content. We therefore aim at detecting random individual error within reviews. Such errors comprise the disagreement in polarity of review texts and the respective ratings. The challenges that thereby arise are (1) the content and sentiment analysis of the review texts and (2) the removal of the random individual errors contained therein. To solve these tasks, we assign polarities to automatically recognized opinion phrases in reviews and then check for divergence in rating and text polarity. The novelty of our approach is that we improve user-generated data quality by excluding error-prone reviews on German physician websites from average ratings.}}, author = {{Geierhos, Michaela and Bäumer, Frederik Simon and Schulze, Sabine and Stuß, Valentina}}, booktitle = {{Proceedings of the 28th International Conference on Industrial, Engineering and Other Applications of Applied Intelligent Systems (IEA/AIE 2015)}}, editor = {{Ali, Moonis and Kwon, Young Sig and Lee, Chang-Hwan and Kim, Juntae and Kim, Yongdai }}, isbn = {{978-3-319-19065-5}}, location = {{Seoul, South Korea}}, pages = {{305--315}}, publisher = {{Springer}}, title = {{{Filtering Reviews by Random Individual Error}}}, doi = {{10.1007/978-3-319-19066-2_30}}, volume = {{9101}}, year = {{2015}}, } @phdthesis{304, author = {{Koutsopoulos, Andreas}}, publisher = {{Universität Paderborn}}, title = {{{Dynamics and Efficiency in Topological Self-Stabilization}}}, year = {{2015}}, } @phdthesis{305, author = {{Kniesburges, Sebastian}}, publisher = {{Universität Paderborn}}, title = {{{Distributed Data Structures and the Power of topological Self-Stabilization}}}, year = {{2015}}, } @phdthesis{270, author = {{Abshoff, Sebastian}}, publisher = {{Universität Paderborn}}, title = {{{On the Complexity of Fundamental Problems in Dynamic Ad-hoc Networks}}}, year = {{2015}}, } @inproceedings{274, abstract = {{Consider the problem in which n jobs that are classified into k types are to be scheduled on m identical machines without preemption. A machine requires a proper setup taking s time units before processing jobs of a given type. The objective is to minimize the makespan of the resulting schedule. We design and analyze an approximation algorithm that runs in time polynomial in n,m and k and computes a solution with an approximation factor that can be made arbitrarily close to 3/2.}}, author = {{Mäcker, Alexander and Malatyali, Manuel and Meyer auf der Heide, Friedhelm and Riechers, Sören}}, booktitle = {{Algorithms and Data Structures: 14th International Symposium, WADS 2015, Victoria, BC, Canada, August 5-7, 2015. Proceedings}}, editor = {{Dehne, Frank and Sack, Jörg Rüdiger and Stege, Ulrike}}, pages = {{542----553}}, title = {{{Non-preemptive Scheduling on Machines with Setup Times}}}, doi = {{10.1007/978-3-319-21840-3_45}}, year = {{2015}}, } @inproceedings{275, abstract = {{We investigate a non-cooperative game-theoretic model for the formation of communication networks by selfish agents. Each agent aims for a central position at minimum cost for creating edges. In particular, the general model (Fabrikant et al., PODC'03) became popular for studying the structure of the Internet or social networks. Despite its significance, locality in this game was first studied only recently (Bilò et al., SPAA'14), where a worst case locality model was presented, which came with a high efficiency loss in terms of quality of equilibria. Our main contribution is a new and more optimistic view on locality: agents are limited in their knowledge and actions to their local view ranges, but can probe different strategies and finally choose the best. We study the influence of our locality notion on the hardness of computing best responses, convergence to equilibria, and quality of equilibria. Moreover, we compare the strength of local versus non-local strategy changes. Our results address the gap between the original model and the worst case locality variant. On the bright side, our efficiency results are in line with observations from the original model, yet we have a non-constant lower bound on the Price of Anarchy.}}, author = {{Cord-Landwehr, Andreas and Lenzner, Pascal}}, booktitle = {{Proceedings of the 40th Conference on Mathematical Foundations of Computer Science (MFCS)}}, pages = {{248----260}}, title = {{{Network Creation Games: Think Global - Act Local}}}, doi = {{10.1007/978-3-662-48054-0_21}}, year = {{2015}}, } @misc{276, author = {{Hohenberger, Till}}, publisher = {{Universität Paderborn}}, title = {{{Network Creation Games with Interest Groups}}}, year = {{2015}}, } @misc{278, author = {{Feldmann, Michael}}, publisher = {{Universität Paderborn}}, title = {{{Monotonic Searchability for distributed sorted Lists and De Bruijn Graphs}}}, year = {{2015}}, } @inproceedings{21505, author = {{Hein, David and Giese, Patrick and Meschut, Gerson and Gumbsch, Peter and Sommer, Silke and Bier, Matthias}}, location = {{Paderborn}}, title = {{{Charakterisierung und Modellierung von mechanischen Fügeverbindungen mit einseitiger Zugänglichkeit für den profilintensiven Leichtbau unter Crashbelastung}}}, year = {{2015}}, } @inproceedings{21506, author = {{Hein, David and Giese, Patrick and Meschut, Gerson and Gumbsch, Peter and Sommer, Silke and Bier, Matthias and Iwainsky, Alfred and Herfert, Daniel and Günther, Matthias}}, booktitle = {{5. Fügetechnisches Gemeinschaftskolloquium}}, location = {{Paderborn}}, title = {{{Daten- und prognosebasierte Generierung von Modellparametern für die Crashsimulation mechanisch gefügter Verbindungen}}}, year = {{2015}}, }