TY - CONF AU - Afifi, Haitham AU - Auroux, Sébastien AU - Karl, Holger ID - 2474 TI - MARVELO: Wireless Virtual Network Embedding for Overlay Graphs with Loops ER - TY - CONF AU - Shiferaw Heyi, Binyam AU - Karl, Holger ID - 2476 TI - Modelling Time-Limited Capacity of a Wireless Channel as aMarkov Reward Process ER - TY - CONF AU - Mohr, Felix AU - Wever, Marcel Dominik AU - Hüllermeier, Eyke AU - Faez, Amin ID - 2479 T2 - SCC TI - (WIP) Towards the Automated Composition of Machine Learning Services ER - TY - CONF AB - Understanding the behavior of the components of service function chains (SFCs) in different load situations is important for efficient and automatic management and orches- tration of services. For this purpose and for practical research in network function virtualization in general, there is a great need for benchmarks and experimental data. In this paper, we describe our experiments for characterizing the relationship between resource demands of virtual network functions (VNFs) and the expected performance of the SFC, considering the individual performance of the VNFs as well as the interdependencies among VNFs within the SFC. We have designed our experiments focusing on video streaming, an important application in this context. We present examples of models for predicting the interdependence between resource demands and performance characteristics of SFCs using support vector regression and polynomial regression models. We also show practical evidence from our experiments that VNFs need to be benchmarked in their final chain setup, rather than individually, to capture important interdependencies that affect their performance. The data gathered from our experiments is publicly available. AU - Dräxler, Sevil AU - Peuster, Manuel AU - Illian, Marvin AU - Karl, Holger ID - 2480 T2 - 4th IEEE International Conference on Network Softwarization (NetSoft 2018) TI - Generating Resource and Performance Models for Service Function Chains: The Video Streaming Case ER - TY - CONF AB - Network function virtualization requires scaling and placement, deciding the number and the location of function instances. Current approaches are limited in flexibility and practical applicability. Specifically, we study dynamic, single-step, joint scaling and placement of network services with bidirectional flows traversing Physical or Virtual Network Functions (VNFs) and returning to their sources. We develop models to support stateful components and legacy network functions with fixed locations in these network services as well as the possibility of reusing VNFs across network services. We formalize the problem of jointly scaling and placing such network services as a mixed- integer linear program (MILP). We show that this problem is NP-complete and also present a heuristic algorithm to find good solutions in short time. In an extensive evaluation with realistic scenarios, we investigate the capabilities of the two approaches. AU - Dräxler, Sevil AU - Schneider, Stefan Balthasar AU - Karl, Holger ID - 2481 T2 - 4th IEEE International Conference on Network Softwarization (NetSoft 2018) TI - Scaling and Placing Bidirectional Services with Stateful Virtual and Physical Network Functions ER - TY - CONF AU - Dräxler, Sevil AU - Karl, Holger AU - Razzaghi Kouchaksaraei, Hadi AU - Machwe, Azahar AU - Dent-Young, Crispin AU - Katsalis, Kostas AU - Samdanis, Konstantinos ID - 2482 T2 - 27th European Conference on Networks and Communications (EUCNC 2018) TI - 5G OS: Control and Orchestration of Services on Multi-Domain Heterogeneous 5G Infrastructures ER - TY - GEN AB - Understanding the behavior of distributed cloud service components in different load situations is important for efficient and automatic management and orchestration of these services. For this purpose and for practical research in distributed cloud computing in general, there is need for benchmarks and experimental data. In this paper, we describe our experiments for characterizing the relationship between resource demands of application components and the expected performance of applica- tions. We present initial results for predicting the interdependence between resource demands and performance characteristics using support vector regression and polynomial regression models. The data gathered from our experiments is publicly available. AU - Dräxler, Sevil AU - Peuster, Manuel AU - Illian, Marvin AU - Karl, Holger ID - 2483 TI - Towards Predicting Resource Demands and Performance of Distributed Cloud Services ER - TY - CONF AB - We study the classic bin packing problem in a fully-dynamic setting, where new items can arrive and old items may depart. We want algorithms with low asymptotic competitive ratio while repacking items sparingly between updates. Formally, each item i has a movement cost c_i >= 0, and we want to use alpha * OPT bins and incur a movement cost gamma * c_i, either in the worst case, or in an amortized sense, for alpha, gamma as small as possible. We call gamma the recourse of the algorithm. This is motivated by cloud storage applications, where fully-dynamic bin packing models the problem of data backup to minimize the number of disks used, as well as communication incurred in moving file backups between disks. Since the set of files changes over time, we could recompute a solution periodically from scratch, but this would give a high number of disk rewrites, incurring a high energy cost and possible wear and tear of the disks. In this work, we present optimal tradeoffs between number of bins used and number of items repacked, as well as natural extensions of the latter measure. AU - Feldkord, Björn AU - Feldotto, Matthias AU - Gupta, Anupam AU - Guruganesh, Guru AU - Kumar, Amit AU - Riechers, Sören AU - Wajc, David ED - Chatzigiannakis, Ioannis ED - Kaklamanis, Christos ED - Marx, Dániel ED - Sannella, Donald ID - 2484 SN - 1868-8969 T2 - 45th International Colloquium on Automata, Languages, and Programming (ICALP 2018) TI - Fully-Dynamic Bin Packing with Little Repacking VL - 107 ER - TY - CONF AU - Feldkord, Björn AU - Meyer auf der Heide, Friedhelm ID - 2485 T2 - Proceedings of the 30th ACM Symposium on Parallelism in Algorithms and Architectures (SPAA) TI - Online Facility Location with Mobile Facilities ER - TY - GEN AU - Szopinski, Daniel AU - Kundisch, Dennis ID - 2490 T2 - 2nd Business Model Conference TI - Business model idea generation: An exploratory study on changing perspectives ER - TY - GEN AU - Szopinski, Daniel ID - 2491 T2 - 2nd Business Model Conference TI - How to teach business model innovation to 300+ students: An experience report ER - TY - GEN AU - Tolksdorf, Nils Frederik AU - Siebert, Scarlet ID - 24928 TI - Raising Robotic Natives? Ethical aspects of learning with robots in kindergarten ER - TY - CHAP AU - Elit, Stefan ID - 24944 T2 - Faust-Handbuch TI - Der sozialistische Faust ER - TY - JOUR AU - Bauer, Anna AU - Sacher, Marc ID - 24953 JF - Phydid B, Didaktik der Physik, Beiträge zur DPG-Frühjahrstagung TI - Kompetenzorientierte, universitäre Laborpraktika - Das Paderborner Physik Praktikum (3P) ER - TY - CHAP AU - Bauer, Anna AU - Reinhold, Peter AU - Sacher, Marc ED - Maurer, Christian ID - 24960 T2 - Qualitätsvoller Chemie- und Physikunterricht – normative und empirische Dimensionen TI - Operationalisierung der experimentellen Kompetenz (Physik)Studierender ER - TY - GEN AB - We consider a group of $n$ autonomous mobile robots of which $m$ are stationary thus cannot move. Robots are represented by points in the Euclidean plane. They have no memory, do not communicate or share a common coordinate system and they move solely based on the positioning of other robots within their limited viewing range of 1. The goal is to gather the robots inside of the convex hull of all stationary robots. A variant of this problem, the general gathering problem, has been studied in various different time models. In this work, we consider a continuous time model, where robots continuously observe their neighbors, compute the next target of movement and move with a speed limit of 1 at any time. Regarding the robots' local strategy, we only study contracting algorithms in which every robot that is positioned on the border of the convex hull of all robots moves into this hull. We present a time bound of $\mathcal{O}(nd)$ for any general contracting algorithms in a configuration with only a single stationary robot. For configurations with more stationary robots, we prove that robots converge against the convex hull of all stationary robots and that no upper bound on the runtime exists. For the specific contracting algorithms Go-To-The-Left, Go-On-Bisector and Go-To-The-Middle, we provide linear time bounds. AU - Liedtke, David Jan ID - 25121 TI - Influence of Stationary Robots on Continuous Robot Formation Problems ER - TY - JOUR AU - Wolk, Andreas AU - Rosenthal, Marta AU - Neuhaus, Stephan AU - Huber, Klaus AU - Brassat, Katharina AU - Lindner, Jörg K. N. AU - Grothe, Richard AU - Grundmeier, Guido AU - Bremser, Wolfgang AU - Wilhelm, René ID - 25304 JF - Scientific Reports SN - 2045-2322 TI - A Novel Lubricant Based on Covalent Functionalized Graphene Oxide Quantum Dots ER - TY - JOUR AU - Rüdiger, Arne A. AU - Brassat, Katharina AU - Lindner, Jörg K. N. AU - Bremser, Wolfgang AU - Strube, Oliver I. ID - 25305 JF - Langmuir SN - 0743-7463 TI - Easily Accessible Protein Nanostructures via Enzyme Mediated Addressing ER - TY - CONF AU - Stüker, Daniel AU - Schöppner, Volker AU - Putzig, Katja AU - Giese, Ulrich ID - 25513 TI - Investigations of High-Speed Rubber Extrusion with Consideration of Melt Homogeneity ER - TY - CONF AU - Stüker, Daniel AU - Schöppner, Volker ID - 25515 TI - Influence of Different Temperature Control Unit (TCU) Settings on Thermal Homogeneity and Throughput in Rubber Extrusion Processes ER -