@inproceedings{777,
  author       = {{Dräxler, Martin and Karl, Holger}},
  booktitle    = {{2013 9th International Wireless Communications and Mobile Computing Conference, IWCMC 2013, Sardinia, Italy, July 1-5, 2013}},
  pages        = {{1181----1186}},
  title        = {{{Cross-layer scheduling for multi-quality video streaming in cellular wireless networks}}},
  doi          = {{10.1109/IWCMC.2013.6583724}},
  year         = {{2013}},
}

@inproceedings{6054,
  author       = {{Menke, Peter and McCrae, John and Cimiano, Philipp}},
  booktitle    = {{Proceedings of the 2nd Workshop on Linked Data in Linguistics (LDL-2013): Representing and linking lexicons, terminologies and other language data}},
  pages        = {{44--52}},
  publisher    = {{ACL}},
  title        = {{{Releasing multimodal data as Linguistic Linked Open Data: An experience report}}},
  year         = {{2013}},
}

@article{476,
  abstract     = {{An elementary h-route ow, for an integer h 1, is a set of h edge- disjoint paths between a source and a sink, each path carrying a unit of ow, and an h-route ow is a non-negative linear combination of elementary h-routeows. An h-route cut is a set of edges whose removal decreases the maximum h-route ow between a given source-sink pair (or between every source-sink pair in the multicommodity setting) to zero. The main result of this paper is an approximate duality theorem for multicommodity h-route cuts and ows, for h 3: The size of a minimum h-route cut is at least f=h and at most O(log4 k f) where f is the size of the maximum h-routeow and k is the number of commodities. The main step towards the proof of this duality is the design and analysis of a polynomial-time approximation algorithm for the minimum h-route cut problem for h = 3 that has an approximation ratio of O(log4 k). Previously, polylogarithmic approximation was known only for h-route cuts for h 2. A key ingredient of our algorithm is a novel rounding technique that we call multilevel ball-growing. Though the proof of the duality relies on this algorithm, it is not a straightforward corollary of it as in the case of classical multicommodity ows and cuts. Similar results are shown also for the sparsest multiroute cut problem.}},
  author       = {{Kolman, Petr and Scheideler, Christian}},
  journal      = {{Theory of Computing Systems}},
  number       = {{2}},
  pages        = {{341--363}},
  publisher    = {{Springer}},
  title        = {{{Towards Duality of Multicommodity Multiroute Cuts and Flows: Multilevel Ball-Growing}}},
  doi          = {{10.1007/s00224-013-9454-3}},
  year         = {{2013}},
}

@inproceedings{477,
  abstract     = {{We consider the k-token dissemination problem, where k initially arbitrarily distributed tokens have to be disseminated to all nodes in a dynamic network (as introduced by Kuhn et al., STOC 2010). In contrast to general dynamic networks, our dynamic networks are unit disk graphs, i.e., nodes are embedded into the Euclidean plane and two nodes are connected if and only if their distance is at most R. Our worst-case adversary is allowed to move the nodes on the plane, but the maximum velocity v_max of each node is limited and the graph must be connected in each round. For this model, we provide almost tight lower and upper bounds for k-token dissemination if nodes are restricted to send only one token per round. It turns out that the maximum velocity v_max is a meaningful parameter to characterize dynamics in our model.}},
  author       = {{Abshoff, Sebastian and Benter, Markus and Cord-Landwehr, Andreas and Malatyali, Manuel and Meyer auf der Heide, Friedhelm}},
  booktitle    = {{Algorithms for Sensor Systems - 9th International Symposium on Algorithms and Experiments for Sensor Systems, Wireless Networks and Distributed Robotics, {ALGOSENSORS} 2013, Sophia Antipolis, France, September 5-6, 2013, Revised Selected Papers}},
  pages        = {{22--34}},
  title        = {{{Token Dissemination in Geometric Dynamic Networks}}},
  doi          = {{10.1007/978-3-642-45346-5_3}},
  year         = {{2013}},
}

@inproceedings{481,
  abstract     = {{Cloud computing offers high availability, dynamic scalability, and elasticity requiring only very little administration. However, this service comes with financial costs. Peer-to-peer systems, in contrast, operate at very low costs but cannot match the quality of service of the cloud. This paper focuses on the case study of Wikipedia and presents an approach to reduce the operational costs of hosting similar websites in the cloud by using a practical peer-to-peer approach. The visitors of the site are joining a Chord overlay, which acts as first cache for article lookups. Simulation results show, that up to 72% of the article lookups in Wikipedia could be answered by other visitors instead of using the cloud.}},
  author       = {{Graffi, Kalman and Bremer, Lars}},
  booktitle    = {{Proceedings of the International Conference on Communications (ICC'13)}},
  pages        = {{3444 -- 3449 }},
  title        = {{{Symbiotic Coupling of P2P and Cloud Systems: The Wikipedia Case}}},
  doi          = {{10.1109/ICC.2013.6655082}},
  year         = {{2013}},
}

@article{9867,
  abstract     = {{We report the piezoelectric properties of CuO-doped hydrothermal (K,Na)NbO3 ceramics that can be applied as hard-type lead-free piezoelectric ceramics. To date, we have succeeded in synthesizing high-quality KNbO3 and NaNbO3 powders by the hydrothermal method, which is based on an ionic reaction at high temperature (around 210 $\,^{\circ}$C) and pressure. Increasing both the piezoelectric constant d and the mechanical quality factor (Qm) is important for resonance-type piezoelectric devices, such as ultrasonic motors and transformers. CuO doping into hydrothermal (K,Na)NbO3 ceramics was examined to realize hard-type lead-free piezoelectric ceramics. By doping with 1.2 mol \% CuO, Qm was increased and the dielectric loss (tan δ) was decreased to 0.5\%. The grain size was also influenced by the amount of CuO doping, which indicates that Qm is related to the density. To achieve a higher Qm value, the grain size is required to be less than 5 µm; however, excessive CuO doping leads to anomalous grain growth. Optimal piezoelectric properties were obtained for 1.2 mol \% CuO-doped (K,Na)NbO3; k31 = 0.32, d31 = -44 pC/N, Qm (radial) = 959, and tan δ= 0.5\%. These characteristics showed that CuO doping with hydrothermal powders is effective for obtaining hard-type ceramics, and the mechanical quality factor is more than ten times higher than that of nondoped hydrothermal (K,Na)NbO3 ceramics. Therefore, compared with the conventional solid-state method, we could succeed in obtaining hard-type ceramics by a simple and short process.}},
  author       = {{Yokouchi, Yuriko and Maeda, Takafumi and Bornmann, Peter and Hemsel, Tobias and Morita, Takeshi}},
  journal      = {{Japanese Journal of Applied Physics}},
  number       = {{7S}},
  title        = {{{Piezoelectric Properties of CuO-Doped (K,Na)NbO3 Lead-Free Ceramics Synthesized with Hydrothermal Powders}}},
  doi          = {{10.7567/JJAP.52.07HB03}},
  volume       = {{52}},
  year         = {{2013}},
}

@misc{503,
  author       = {{Blix, Andreas}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Optimale und adaptive binäre Bäume in Netzwerken}}},
  year         = {{2013}},
}

@inbook{5031,
  author       = {{Becker, Jörg and Bernhold, Torben and Beverungen, Daniel and Kaling, Nina and Knackstedt, Ralf and Vanessa, Lellek and Peter Rauer, Hans}},
  booktitle    = {{Dienstleistungsmodellierung 2012: Product-Service Systems und Produktivität}},
  editor       = {{Thomas, Oliver and Nüttgens, Markus}},
  pages        = {{208----226}},
  title        = {{{Softwaregestützte Konstruktion von Produktivitätsmodellen im Facility Management}}},
  doi          = {{10.1007/978-3-658-00863-5}},
  year         = {{2013}},
}

@inproceedings{507,
  abstract     = {{We study two-party communication in the context of directed dynamic networks that are controlled by an adaptive adversary. This adversary is able to change all edges as long as the networks stay strongly-connected in each round. In this work, we establish a relation between counting the total number of nodes in the network and the problem of exchanging tokens between two communication partners which communicate through a dynamic network. We show that the communication problem for a constant fraction of n tokens in a dynamic network with n nodes is at most as hard as counting the number of nodes in a dynamic network with at most 4n+3 nodes. For the proof, we construct a family of directed dynamic networks and apply a lower bound from two-party communication complexity.}},
  author       = {{Abshoff, Sebastian and Benter, Markus and Malatyali, Manuel and Meyer auf der Heide, Friedhelm}},
  booktitle    = {{Proceedings of the 17th International Conference on Principles of Distributed Systems (OPODIS)}},
  pages        = {{11--22}},
  title        = {{{On Two-Party Communication Through Dynamic Networks}}},
  doi          = {{10.1007/978-3-319-03850-6_2}},
  year         = {{2013}},
}

@misc{510,
  author       = {{Jayesh Parekh, Chintan}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Meta-data based Search in Structured Peer-to-Peer Networks}}},
  year         = {{2013}},
}

@inproceedings{513,
  abstract     = {{This paper initiates the study of self-adjusting networks (or distributed data structures) whose topologies dynamically adapt to a communication pattern $\sigma$. We present a fully decentralized self-adjusting solution called SplayNet. A SplayNet is a distributed generalization of the classic splay tree concept. It ensures short paths (which can be found using local-greedy routing) between communication partners while minimizing topological rearrangements. We derive an upper bound for the amortized communication cost of a SplayNet based on empirical entropies of $\sigma$, and show that SplayNets have several interesting convergence properties. For instance, SplayNets features a provable online optimality under special requests scenarios. We also investigate the optimal static network and prove different lower bounds for the average communication cost based on graph cuts and on the empirical entropy of the communication pattern $\sigma$. From these lower bounds it follows, e.g., that SplayNets are optimal in scenarios where the requests follow a product distribution as well. Finally, this paper shows that in contrast to the Minimum Linear Arrangement problem which is generally NP-hard, the optimal static tree network can be computed in polynomial time for any guest graph, despite the exponentially large graph family. We complement our formal analysis with a small simulation study on a Facebook graph.}},
  author       = {{Avin, Chen and Häupler, Bernhard and Lotker, Zvi and Scheideler, Christian and Schmid, Stefan}},
  booktitle    = {{Proceedings of the 27th IEEE International Parallel and Distributed Processing Symposium (IPDPS)}},
  pages        = {{395--406}},
  title        = {{{Locally Self-Adjusting Tree Networks}}},
  doi          = {{10.1109/IPDPS.2013.40}},
  year         = {{2013}},
}

@phdthesis{514,
  abstract     = {{Diese Arbeit besch{\"a}ftigt sich mit dem Facility Location Problem. Dies ist ein Optimierungsproblem, bei dem festgelegt werden muss an welchen Positionen Ressourcen zur Verf{\"u}gung gestellt werden, so dass diese von Nutzern gut erreicht werden k{\"o}nnen. Es sollen dabei Kosten minimiert werden, die zum einen durch Bereitstellung von Ressourcen und zum anderen durch Verbindungskosten zwischen Nutzern und Ressourcen entstehen. Die Schwierigkeit des Problems liegt darin, dass man einerseits m{\"o}glichst wenige Ressourcen zur Verf{\"u}gung stellen m{\"o}chte, andererseits daf{\"u}r sorgen muss, dass sich Nutzer nicht all zu weit weg von Ressourcen befinden. Dies w{\"u}rde n{\"a}mlich hohe Verbindungskosten nach sich ziehen. Das Facility Location Problem wurde bereits sehr intensiv in vielen unterschiedlichen Varianten untersucht. In dieser Arbeit werden drei Varianten des Problems modelliert und neue Algorithmen f{\"u}r sie entwickelt und bez{\"u}glich ihres Approximationsfaktors und ihrer Laufzeit analysiert. Jede dieser drei untersuchten Varianten hat einen besonderen Schwerpunkt. Bei der ersten Varianten handelt es sich um ein Online Problem, da hier die Eingabe nicht von Anfang an bekannt ist, sondern Schritt f{\"u}r Schritt enth{\"u}llt wird. Die Schwierigkeit hierbei besteht darin unwiderrufliche Entscheidungen treffen zu m{\"u}ssen ohne dabei die Zukunft zu kennen und trotzdem eine zu jeder Zeit gute L{\"o}sung angeben zu k{\"o}nnen. Der Schwerpunkt der zweiten Variante liegt auf Lokalit{\"a}t, die z.B. in Sensornetzwerken von großer Bedeutung ist. Hier soll eine L{\"o}sung verteilt und nur mit Hilfe von lokalen Information berechnet werden. Schließlich besch{\"a}ftigt sich die dritte Variante mit einer verteilten Berechnung, bei welcher nur eine stark beschr{\"a}nkte Datenmenge verschickt werden darf und dabei trotzdem ein sehr guter Approximationsfaktor erreicht werden muss. Die bei der Analyse der Approximationsfaktoren bzw. der Kompetitivit{\"a}t verwendeten Techniken basieren zum großen Teil auf Absch{\"a}tzung der primalen L{\"o}sung mit Hilfe einer L{\"o}sung des zugeh{\"o}rigen dualen Problems. F{\"u}r die Modellierung von Lokalit{\"a}t wird das weitverbreitete LOCAL Modell verwendet. In diesem Modell werden f{\"u}r die Algorithmen subpolynomielle obere Laufzeitschranken gezeigt.}},
  author       = {{Pietrzyk, Peter}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Local and Online Algorithms for Facility Location}}},
  year         = {{2013}},
}

@misc{522,
  author       = {{Feldotto, Matthias}},
  publisher    = {{Universität Paderborn}},
  title        = {{{HSkip+: A Self-Stabilizing Overlay Network for Nodes with Heterogeneous Bandwidths}}},
  year         = {{2013}},
}

@unpublished{524,
  abstract     = {{We study the complexity theory for the local distributed setting introduced by Korman, Peleg and Fraigniaud. They have defined three complexity classes LD (Local Decision), NLD (Nondeterministic Local Decision) and NLD^#n. The class LD consists of all languages which can be decided with a constant number of communication rounds. The class NLD consists of all languages which can be verified by a nondeterministic algorithm with a constant number of communication rounds. In order to define the nondeterministic classes, they have transferred the notation of nondeterminism into the distributed setting by the use of certificates and verifiers. The class NLD^#n consists of all languages which can be verified by a nondeterministic algorithm where each node has access to an oracle for the number of nodes. They have shown the hierarchy LD subset NLD subset NLD^#n. Our main contributions are strict hierarchies within the classes defined by Korman, Peleg and Fraigniaud. We define additional complexity classes: the class LD(t) consists of all languages which can be decided with at most t communication rounds. The class NLD-O(f) consists of all languages which can be verified by a local verifier such that the size of the certificates that are needed to verify the language are bounded by a function from O(f). Our main results are refined strict hierarchies within these nondeterministic classes.}},
  author       = {{Meyer auf der Heide, Friedhelm and Swirkot, Kamil}},
  publisher    = {{arXiv}},
  title        = {{{Hierarchies in Local Distributed Decision}}},
  year         = {{2013}},
}

@misc{526,
  author       = {{Mäcker, Alexander}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Greedy Network Creation With Heavy And Light Edges}}},
  year         = {{2013}},
}

@misc{537,
  author       = {{Heindorf, Stefan}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Dispersion of Multi-Robot Teams}}},
  year         = {{2013}},
}

@inproceedings{541,
  abstract     = {{Existing solutions for gossip-based aggregation in peer-to-peer networks use epochs to calculate a global estimation from an initial static set of local values. Once the estimation converges system-wide, a new epoch is started with fresh initial values. Long epochs result in precise estimations based on old measurements and short epochs result in imprecise aggregated estimations. In contrast to this approach, we present in this paper a continuous, epoch-less approach which considers fresh local values in every round of the gossip-based aggregation. By using an approach for dynamic information aging, inaccurate values and values from left peers fade from the aggregation memory. Evaluation shows that the presented approach for continuous information aggregation in peer-to-peer systems monitors the system performance precisely, adapts to changes and is lightweight to operate.}},
  author       = {{Graffi, Kalman and Rapp, Vitaly}},
  booktitle    = {{Proceedings of the International Conference on Computer Communications and Networks (ICCCN'13)}},
  pages        = {{1--7}},
  title        = {{{Continuous Gossip-based Aggregation through Dynamic Information Aging}}},
  doi          = {{10.1109/ICCCN.2013.6614118}},
  year         = {{2013}},
}

@inproceedings{544,
  abstract     = {{Comparative evaluations of peer-to-peer protocols through simulations are a viable approach to judge the performance and costs of the individual protocols in large-scale networks. In order to support this work, we enhanced the peer-to-peer systems simulator PeerfactSim.KOM with a fine-grained analyzer concept, with exhaustive automated measurements and gnuplot generators as well as a coordination control to evaluate a set of experiment setups in parallel. Thus, by configuring all experiments and protocols only once and starting the simulator, all desired measurements are performed, analyzed, evaluated and combined, resulting in a holistic environment for the comparative evaluation of peer-to-peer systems.}},
  author       = {{Feldotto, Matthias and Graffi, Kalman}},
  booktitle    = {{Proceedings of the International Conference on High Performance Computing and Simulation (HPCS'13)}},
  pages        = {{99--106}},
  title        = {{{Comparative Evaluation of Peer-to-Peer Systems Using PeerfactSim.KOM}}},
  doi          = {{10.1109/HPCSim.2013.6641399}},
  year         = {{2013}},
}

@misc{545,
  author       = {{Blumentritt, Fritz}},
  publisher    = {{Universität Paderborn}},
  title        = {{{Cliquenbildung in verteilten Systemen}}},
  year         = {{2013}},
}

@inproceedings{546,
  abstract     = {{Self-stabilization is the property of a system to transfer itself regardless of the initial state into a legitimate state. Chord as a simple, decentralized and scalable distributed hash table is an ideal showcase to introduce self-stabilization for p2p overlays. In this paper, we present Re-Chord, a self-stabilizing version of Chord. We show, that the stabilization process is functional, but prone to strong churn. For that, we present Ca-Re-Chord, a churn resistant version of Re-Chord, that allows the creation of a useful DHT in any kind of graph regardless of the initial state. Simulation results attest the churn resistance and good performance of Ca-Re-Chord.}},
  author       = {{Graffi, Kalman and Benter, Markus and Divband, Mohammad and Kniesburges, Sebastian and Koutsopoulos, Andreas}},
  booktitle    = {{Proceedings of the Conference on Networked Systems (NetSys)}},
  pages        = {{27--34}},
  title        = {{{Ca-Re-Chord: A Churn Resistant Self-stabilizing Chord Overlay Network}}},
  doi          = {{10.1109/NetSys.2013.11}},
  year         = {{2013}},
}