TY - CONF
AU - Berssenbrügge, Jan
AU - Wiederkehr, Olga
AU - Jähn, Claudius
AU - Fischer, Matthias
ID - 17425
T2 - 12. Paderborner Workshop Augmented & Virtual Reality in der Produktentstehung
TI - Anbindung des Virtuellen Prototypen an die Partialmodelle intelligenter technischer Systeme
VL - 343
ER -
TY - CONF
AB - Consider n nodes connected to a single coordinator. Each node receives an
individual online data stream of numbers and, at any point in time, the
coordinator has to know the k nodes currently observing the largest values, for
a given k between 1 and n. We design and analyze an algorithm that solves this
problem while bounding the amount of messages exchanged between the nodes and
the coordinator. Our algorithm employs the idea of using filters which,
intuitively speaking, leads to few messages to be sent, if the new input is
"similar" to the previous ones. The algorithm uses a number of messages that is
on expectation by a factor of O((log {\Delta} + k) log n) larger than that of
an offline algorithm that sets filters in an optimal way, where {\Delta} is
upper bounded by the largest value observed by any node.
AU - Mäcker, Alexander
AU - Malatyali, Manuel
AU - Meyer auf der Heide, Friedhelm
ID - 16460
T2 - Proceedings of the 29th International Parallel and Distributed Processing Symposium (IPDPS)
TI - Online Top-k-Position Monitoring of Distributed Data Streams
ER -
TY - CONF
AU - Hamann, Heiko
AU - Schmickl, Thomas
AU - Zahadat, Payam
ID - 19988
T2 - 13th European Conference on Artificial Life (ECAL 2015)
TI - Evolving Collective Behaviors With Diverse But Predictable Sensor States
ER -
TY - CONF
AU - Ding, Hongli
AU - Hamann, Heiko
ID - 19990
T2 - First International Symposium on Swarm Behavior and Bio-Inspired Robotics (SWARM 2015)
TI - Dependability in Swarm Robotics: Error Detection and Correction
ER -
TY - CONF
AU - Dorigo, Marco
AU - Hamann, Heiko
AU - Valentini, Gabriele
ID - 20005
T2 - Proceedings of the 14th Int. Conf. on Autonomous Agents and Multiagent Systems (AAMAS 2015)
TI - Efficient Decision-Making in a Self-Organizing Robot Swarm: On the Speed Versus Accuracy Trade-Off
ER -
TY - JOUR
AB - Abstract We study the problem of bandwidth allocation with multiple interferences. In this problem the input consists of a set of users and a set of base stations. Each user has a list of requests, each consisting of a base station, a frequency demand, and a profit that may be gained by scheduling this request. The goal is to find a maximum profit set of user requests S that satisfies the following conditions: (i) S contains at most one request per user, (ii) the frequency sets allotted to requests in S that correspond to the same base station are pairwise non-intersecting, and (iii) the QoS received by any user at any frequency is reasonable according to an interference model. In this paper we consider two variants of bandwidth allocation with multiple interferences. In the first each request specifies a demand that can be satisfied by any subset of frequencies that is large enough. In the second each request specifies a specific frequency interval. Furthermore, we consider two interference models, multiplicative and additive. We show that these problems are extremely hard to approximate if the interferences depend on both the interfered and the interfering base stations. On the other hand, we provide constant factor approximation algorithms for both variants of bandwidth allocation with multiple interferences for the case where the interferences depend only on the interfering base stations. We also consider a restrictive special case that is closely related to the Knapsack problem. We show that this special case is NP-hard and that it admits an FPTAS.
AU - Bar-Yehuda, Reuven
AU - Polevoy, Gleb
AU - Rawitz, Dror
ID - 17658
JF - Discrete Applied Mathematics
KW - Local ratio
SN - 0166-218X
TI - Bandwidth allocation in cellular networks with multiple interferences
VL - 194
ER -
TY - CONF
AB - In this paper we study the potential function in congestion games. We consider both games with non-decreasing cost functions as well as games with non-increasing utility functions. We show that the value of the potential function $\Phi(\sf s)$ of any outcome $\sf s$ of a congestion game approximates the optimum potential value $\Phi(\sf s^*)$ by a factor $\Psi_{\mathcal{F}}$ which only depends on the set of cost/utility functions $\mathcal{F}$, and an additive term which is bounded by the sum of the total possible improvements of the players in the outcome $\sf s$. The significance of this result is twofold. On the one hand it provides \emph{Price-of-Anarchy}-like results with respect to the potential function. On the other hand, we show that these approximations can be used to compute $(1+\varepsilon)\cdot\Psi_{\mathcal{F}}$-approximate pure Nash equilibria for congestion games with non-decreasing cost functions. For the special case of polynomial cost functions, this significantly improves the guarantees from Caragiannis et al. [FOCS 2011]. Moreover, our machinery provides the first guarantees for general latency functions.
AU - Feldotto, Matthias
AU - Gairing, Martin
AU - Skopalik, Alexander
ID - 453
T2 - Proceedings of the 10th International Conference on Web and Internet Economics (WINE)
TI - Bounding the Potential Function in Congestion Games and Approximate Pure Nash Equilibria
ER -
TY - CONF
AB - Collective decision making in self-organized systems is challenging because it relies on local perception and local communication. Globally defined qualities such as consensus time and decision accuracy are both difficult to predict and difficult to guarantee. We present the weighted voter model which implements a self-organized collective decision making process. We provide an ODE model, a master equation model (numerically solved by the Gillespie algorithm), and agent-based simulations of the proposed decision-making strategy. This set of models enables us to investigate the system behavior in the thermodynamic limit and to investigate finite-size effects due to random fluctuations. Based on our results, we give minimum requirements to guarantee consensus on the optimal decision, a minimum swarm size to guarantee a certain accuracy, and we show that the proposed approach scales with system size and is robust to noise.
AU - Dorigo, Marco
AU - Hamann, Heiko
AU - Valentini, Gabriele
AU - Lomuscio, Alessio
AU - Scerri, Paul
AU - Bazzan, Ana
AU - Huhns, Michael
ID - 20121
T2 - Proceedings of the 13th Int. Conf. on Autonomous Agents and Multiagent Systems (AAMAS 2014)
TI - Self-Organized Collective Decision Making: The Weighted Voter Model
ER -
TY - CONF
AU - Hamann, Heiko
ID - 20126
T2 - Int. Conf. on Genetic and Evolutionary Computation (GECCO 2014)
TI - Evolving Prediction Machines: Collective Behaviors Based on Minimal Surprisal
ER -
TY - CONF
AU - King, Thomas C.
AU - Liu, Qingzhi
AU - Polevoy, Gleb
AU - de Weerdt, Mathijs
AU - Dignum, Virginia
AU - van Riemsdijk, M. Birna
AU - Warnier, Martijn
ID - 17661
KW - crowd-sensing
KW - crowdsourcing
KW - data aggregation
KW - game theory
KW - norms
KW - reciprocation
KW - self interested agents
KW - simulation
SN - 978-1-4503-2738-1
T2 - Proceedings of the 2014 International Conference on Autonomous Agents and Multi-agent Systems
TI - Request Driven Social Sensing
ER -
TY - CONF
AU - Polevoy, Gleb
AU - Trajanovski, Stojan
AU - de Weerdt, Mathijs M.
ID - 17659
KW - competition
KW - equilibrium
KW - market
KW - models
KW - shared effort games
KW - simulation
SN - 978-1-4503-2738-1
T2 - Proceedings of the 2014 International Conference on Autonomous Agents and Multi-agent Systems
TI - Nash Equilibria in Shared Effort Games
ER -
TY - CONF
AB - We consider a multilevel network game, where nodes can improvetheir communication costs by connecting to a high-speed network.The n nodes are connected by a static network and each node can decideindividually to become a gateway to the high-speed network. The goalof a node v is to minimize its private costs, i.e., the sum (SUM-game) ormaximum (MAX-game) of communication distances from v to all othernodes plus a fixed price α > 0 if it decides to be a gateway. Between gatewaysthe communication distance is 0, and gateways also improve othernodes’ distances by behaving as shortcuts. For the SUM-game, we showthat for α ≤ n − 1, the price of anarchy is Θ (n/√α) and in this rangeequilibria always exist. In range α ∈ (n−1, n(n−1)) the price of anarchyis Θ(√α), and for α ≥ n(n − 1) it is constant. For the MAX-game, weshow that the price of anarchy is either Θ (1 + n/√α), for α ≥ 1, orelse 1. Given a graph with girth of at least 4α, equilibria always exist.Concerning the dynamics, both games are not potential games. For theSUM-game, we even show that it is not weakly acyclic.
AU - Abshoff, Sebastian
AU - Cord-Landwehr, Andreas
AU - Jung, Daniel
AU - Skopalik, Alexander
ID - 395
T2 - Proceedings of the 10th International Conference on Web and Internet Economics (WINE)
TI - Multilevel Network Games
ER -
TY - CONF
AB - We give a polynomial time algorithm to compute an optimal energy and fractional weighted flow trade-off schedule for a speed-scalable processor with discrete speeds.Our algorithm uses a geometric approach that is based on structural properties obtained from a primal-dual formulation of the problem.
AU - Antoniadis, Antonios
AU - Barcelo, Neal
AU - Consuegra, Mario
AU - Kling, Peer
AU - Nugent, Michael
AU - Pruhs, Kirk
AU - Scquizzato, Michele
ID - 435
T2 - Proceedings of the 31st Symposium on Theoretical Aspects of Computer Science (STACS)
TI - Efficient Computation of Optimal Energy and Fractional Weighted Flow Trade-off Schedules
ER -
TY - CONF
AB - In this survey article, we discuss two algorithmic research areas that emerge from problems that arise when resources are offered in the cloud. The first area, online leasing, captures problems arising from the fact that resources in the cloud are not bought, but leased by cloud vendors. The second area, Distributed Storage Systems, deals with problems arising from so-called cloud federations, i.e., when several cloud providers are needed to fulfill a given task.
AU - Kniesburges, Sebastian
AU - Markarian, Christine
AU - Meyer auf der Heide, Friedhelm
AU - Scheideler, Christian
ID - 459
T2 - Proceedings of the 21st International Colloquium on Structural Information and Communication Complexity (SIROCCO)
TI - Algorithmic Aspects of Resource Management in the Cloud
ER -
TY - CONF
AU - Hamann, Heiko
AU - Karsai, Istvan
AU - Schmickl, Thomas
AU - Hilbun, Allison
ID - 20007
T2 - Symposium on Biomathematics and Ecology: Education and Research
TI - The common stomach: Organizing task allocation in wasp societies
ER -
TY - CONF
AU - Birattari, Mauro
AU - Dorigo, Marco
AU - Hamann, Heiko
AU - Garnier, Simon
AU - Montes de Oca, Marco
AU - Solnon, Christine
AU - Stuetzle, Thomas
AU - Ding, Hongli
ID - 20127
T2 - Ninth Int. Conf. on Swarm Intelligence (ANTS 2014)
TI - Sorting in Swarm Robots Using Communication-Based Cluster Size Estimation
VL - 8667
ER -
TY - JOUR
AU - Polevoy, Gleb
AU - Smorodinsky, Rann
AU - Tennenholtz, Moshe
ID - 17662
IS - 1
JF - ACM Trans. Econ. Comput.
KW - Competition
KW - efficiency
KW - equilibrium
KW - market
KW - social welfare
SN - 2167-8375
TI - Signaling Competition and Social Welfare
VL - 2
ER -
TY - THES
AB - In meiner Dissertation besch{\"a}ftige ich mich mit dem Entwurf und der Analyse energieeffizienter Schedulingalgorithmen, insbesondere f{\"u}r sogenannte Speed-Scaling Modelle. Diese stellen das theoretische Pendant von Techniken wie AMDs PowerNOW! und Intels SpeedStep dar, welche es erlauben die Geschwindigkeit von Prozessoren zur Laufzeit an die derzeitigen Bedingungen anzupassen. Theoretische Untersuchungen solcher Modelle sind auf eine Arbeit von Yao, Demers und Shenker (FOCS'95) zur{\"u}ckzuf{\"u}hren. Hier kombinieren die Autoren klassisches Deadline-Scheduling mit einem Prozessor der Speed-Scaling beherrscht. Es gilt Jobs verschiedener Gr{\"o}ße fristgerecht abzuarbeiten und die dabei verwendete Energie zu minimieren. Der Energieverbrauch des Prozessors wird durch eine konvexe Funktion $\POW\colon\R_{\geq0}\to\R_{\geq0}$ modelliert, welche die Geschwindigkeit auf den Energieverbrauch abbildet.Meine Dissertation betrachtet verschiedene Varianten des urspr{\"u}nglichen Speed-Scaling Modells. Forschungsrelevante Ergebnisse sind in den Kapiteln 3 bis 6 zu finden und erstrecken sich {\"u}ber die im Folgenden beschriebenen Aspekte:- Kapitel 3 und 4 betrachten verschiedene \emph{Price-Collecting} Varianten des Originalproblems. Hier d{\"u}rfen einzelne Deadlines verfehlt werden, sofern eine jobabh{\"a}ngige Strafe gezahlt wird. Ich entwerfe insbesondere Online-Algorithmen mit einer beweisbar guten Competitiveness. Dabei liefern meine Ergebnisse substantielle Verbesserungen bestehender Arbeiten und erweitern diese unter Anderem auf Szenarien mit mehreren Prozessoren.- In Kapitel 5 wird statt des klassischen Deadline-Schedulings eine Linearkombination der durchschnittlichen Antwortzeit und des Energieverbrauchs betrachtet. Die Frage, ob dieses Problem NP-schwer ist, stellt eine der zentralen Forschungsfragen in diesem Gebiet dar. F{\"u}r eine relaxierte Form dieser Frage entwerfe ich einen effizienter Algorithmus und beweise seine Optimalit{\"a}t.- Das letzte Kapitel betrachtet ein Modell, welches – auf den ersten Blick – nicht direkt zur Speed-Scaling Literatur z{\"a}hlt. Hier geht es stattdessen um ein allgemeines Resource-Constrained Scheduling, in dem sich die Prozessoren zusammen eine gemeinsame, beliebig aufteilbare Ressource teilen. Ich untersuche die Komplexit{\"a}t des Problems und entwerfe verschiedene Approximationsalgorithmen.
AU - Kling, Peter
ID - 431
TI - Energy-efficient Scheduling Algorithms
ER -
TY - CONF
AB - In this paper we present and analyze HSkip+, a self-stabilizing overlay network for nodes with arbitrary heterogeneous bandwidths. HSkip+ has the same topology as the Skip+ graph proposed by Jacob et al. [PODC 2009] but its self-stabilization mechanism significantly outperforms the self-stabilization mechanism proposed for Skip+. Also, the nodes are now ordered according to their bandwidths and not according to their identifiers. Various other solutions have already been proposed for overlay networks with heterogeneous bandwidths, but they are not self-stabilizing. In addition to HSkip+ being self-stabilizing, its performance is on par with the best previous bounds on the time and work for joining or leaving a network of peers of logarithmic diameter and degree and arbitrary bandwidths. Also, the dilation and congestion for routing messages is on par with the best previous bounds for such networks, so that HSkip+ combines the advantages of both worlds. Our theoretical investigations are backed by simulations demonstrating that HSkip+ is indeed performing much better than Skip+ and working correctly under high churn rates.
AU - Feldotto, Matthias
AU - Scheideler, Christian
AU - Graffi, Kalman
ID - 412
T2 - Proceedings of the 14th IEEE International Conference on Peer-to-Peer Computing (P2P)
TI - HSkip+: A Self-Stabilizing Overlay Network for Nodes with Heterogeneous Bandwidths
ER -
TY - GEN
AU - Pahl, David
ID - 373
TI - Reputationssysteme für zusammengesetzte Dienstleistungen
ER -