@inproceedings{30212, author = {{Vorbohle, Christian and Kundisch, Dennis}}, title = {{{Key Properties of Sustainable Business Ecosystem Relationships}}}, year = {{2022}}, } @inproceedings{32811, abstract = {{The decentralized nature of multi-agent systems requires continuous data exchange to achieve global objectives. In such scenarios, Age of Information (AoI) has become an important metric of the freshness of exchanged data due to the error-proneness and delays of communication systems. Communication systems usually possess dependencies: the process describing the success or failure of communication is highly correlated when these attempts are ``close'' in some domain (e.g. in time, frequency, space or code as in wireless communication) and is, in general, non-stationary. To study AoI in such scenarios, we consider an abstract event-based AoI process $\Delta(n)$, expressing time since the last update: If, at time $n$, a monitoring node receives a status update from a source node (event $A(n-1)$ occurs), then $\Delta(n)$ is reset to one; otherwise, $\Delta(n)$ grows linearly in time. This AoI process can thus be viewed as a special random walk with resets. The event process $A(n)$ may be nonstationary and we merely assume that its temporal dependencies decay sufficiently, described by $\alpha$-mixing. We calculate moment bounds for the resulting AoI process as a function of the mixing rate of $A(n)$. Furthermore, we prove that the AoI process $\Delta(n)$ is itself $\alpha$-mixing from which we conclude a strong law of large numbers for $\Delta(n)$. These results are new, since AoI processes have not been studied so far in this general strongly mixing setting. This opens up future work on renewal processes with non-independent interarrival times.}}, author = {{Redder, Adrian and Ramaswamy, Arunselvan and Karl, Holger}}, booktitle = {{Proceedings of the 58th Allerton Conference on Communication, Control, and Computing}}, title = {{{Age of Information Process under Strongly Mixing Communication -- Moment Bound, Mixing Rate and Strong Law}}}, year = {{2022}}, } @inproceedings{30793, author = {{Redder, Adrian and Ramaswamy, Arunselvan and Karl, Holger}}, booktitle = {{Proceedings of the 14th International Conference on Agents and Artificial Intelligence}}, publisher = {{SCITEPRESS - Science and Technology Publications}}, title = {{{Multi-agent Policy Gradient Algorithms for Cyber-physical Systems with Lossy Communication}}}, doi = {{10.5220/0010845400003116}}, year = {{2022}}, } @unpublished{30790, abstract = {{Iterative distributed optimization algorithms involve multiple agents that communicate with each other, over time, in order to minimize/maximize a global objective. In the presence of unreliable communication networks, the Age-of-Information (AoI), which measures the freshness of data received, may be large and hence hinder algorithmic convergence. In this paper, we study the convergence of general distributed gradient-based optimization algorithms in the presence of communication that neither happens periodically nor at stochastically independent points in time. We show that convergence is guaranteed provided the random variables associated with the AoI processes are stochastically dominated by a random variable with finite first moment. This improves on previous requirements of boundedness of more than the first moment. We then introduce stochastically strongly connected (SSC) networks, a new stochastic form of strong connectedness for time-varying networks. We show: If for any $p \ge0$ the processes that describe the success of communication between agents in a SSC network are $\alpha$-mixing with $n^{p-1}\alpha(n)$ summable, then the associated AoI processes are stochastically dominated by a random variable with finite $p$-th moment. In combination with our first contribution, this implies that distributed stochastic gradient descend converges in the presence of AoI, if $\alpha(n)$ is summable.}}, author = {{Redder, Adrian and Ramaswamy, Arunselvan and Karl, Holger}}, booktitle = {{arXiv:2201.11343}}, title = {{{Distributed gradient-based optimization in the presence of dependent aperiodic communication}}}, year = {{2022}}, } @unpublished{30791, abstract = {{We present sufficient conditions that ensure convergence of the multi-agent Deep Deterministic Policy Gradient (DDPG) algorithm. It is an example of one of the most popular paradigms of Deep Reinforcement Learning (DeepRL) for tackling continuous action spaces: the actor-critic paradigm. In the setting considered herein, each agent observes a part of the global state space in order to take local actions, for which it receives local rewards. For every agent, DDPG trains a local actor (policy) and a local critic (Q-function). The analysis shows that multi-agent DDPG using neural networks to approximate the local policies and critics converge to limits with the following properties: The critic limits minimize the average squared Bellman loss; the actor limits parameterize a policy that maximizes the local critic's approximation of $Q_i^*$, where $i$ is the agent index. The averaging is with respect to a probability distribution over the global state-action space. It captures the asymptotics of all local training processes. Finally, we extend the analysis to a fully decentralized setting where agents communicate over a wireless network prone to delays and losses; a typical scenario in, e.g., robotic applications.}}, author = {{Redder, Adrian and Ramaswamy, Arunselvan and Karl, Holger}}, booktitle = {{arXiv:2201.00570}}, title = {{{Asymptotic Convergence of Deep Multi-Agent Actor-Critic Algorithms}}}, year = {{2022}}, } @misc{32398, author = {{Siek, Hanna}}, title = {{{Bringing Structure to Structure-Preserving Signatures: Overview, Implementation and Comparison of Selected SPS Schemes}}}, year = {{2022}}, } @misc{31485, author = {{Kramer, Paul}}, title = {{{On Transforming Lattice-Based Cryptography to the Ring Setting}}}, year = {{2022}}, } @article{32854, author = {{Redder, Adrian and Ramaswamy, Arunselvan and Karl, Holger}}, journal = {{IFAC-PapersOnLine}}, number = {{13}}, pages = {{133–138}}, publisher = {{Elsevier}}, title = {{{Practical Network Conditions for the Convergence of Distributed Optimization}}}, volume = {{55}}, year = {{2022}}, } @inproceedings{33253, author = {{Hansmeier, Tim and Brede, Mathis and Platzner, Marco}}, booktitle = {{GECCO '22: Proceedings of the Genetic and Evolutionary Computation Conference Companion}}, location = {{Boston, MA, USA}}, pages = {{2071--2079}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{XCS on Embedded Systems: An Analysis of Execution Profiles and Accelerated Classifier Deletion}}}, doi = {{10.1145/3520304.3533977}}, year = {{2022}}, } @inproceedings{33491, author = {{Maack, Marten and Pukrop, Simon and Rasmussen, Anna Rodriguez}}, booktitle = {{30th Annual European Symposium on Algorithms, ESA 2022, September 5-9, 2022, Berlin/Potsdam, Germany}}, editor = {{Chechik, Shiri and Navarro, Gonzalo and Rotenberg, Eva and Herman, Grzegorz}}, pages = {{77:1–77:13}}, publisher = {{Schloss Dagstuhl - Leibniz-Zentrum für Informatik}}, title = {{{(In-)Approximability Results for Interval, Resource Restricted, and Low Rank Scheduling}}}, doi = {{10.4230/LIPIcs.ESA.2022.77}}, volume = {{244}}, year = {{2022}}, } @phdthesis{29769, abstract = {{Wettstreit zwischen der Entwicklung neuer Hardwaretrojaner und entsprechender Gegenmaßnahmen beschreiten Widersacher immer raffiniertere Wege um Schaltungsentwürfe zu infizieren und dabei selbst fortgeschrittene Test- und Verifikationsmethoden zu überlisten. Abgesehen von den konventionellen Methoden um einen Trojaner in eine Schaltung für ein Field-programmable Gate Array (FPGA) einzuschleusen, können auch die Entwurfswerkzeuge heimlich kompromittiert werden um einen Angreifer dabei zu unterstützen einen erfolgreichen Angriff durchzuführen, der zum Beispiel Fehlfunktionen oder ungewollte Informationsabflüsse bewirken kann. Diese Dissertation beschäftigt sich hauptsächlich mit den beiden Blickwinkeln auf Hardwaretrojaner in rekonfigurierbaren Systemen, einerseits der Perspektive des Verteidigers mit einer Methode zur Erkennung von Trojanern auf der Bitstromebene, und andererseits derjenigen des Angreifers mit einer neuartigen Angriffsmethode für FPGA Trojaner. Für die Verteidigung gegen den Trojaner ``Heimtückische LUT'' stellen wir die allererste erfolgreiche Gegenmaßnahme vor, die durch Verifikation mittels Proof-carrying Hardware (PCH) auf der Bitstromebene direkt vor der Konfiguration der Hardware angewendet werden kann, und präsentieren ein vollständiges Schema für den Entwurf und die Verifikation von Schaltungen für iCE40 FPGAs. Für die Gegenseite führen wir einen neuen Angriff ein, welcher bösartiges Routing im eingefügten Trojaner ausnutzt um selbst im fertigen Bitstrom in einem inaktiven Zustand zu verbleiben: Hierdurch kann dieser neuartige Angriff zur Zeit weder von herkömmlichen Test- und Verifikationsmethoden, noch von unserer vorher vorgestellten Verifikation auf der Bitstromebene entdeckt werden.}}, author = {{Ahmed, Qazi Arbab}}, keywords = {{FPGA Security, Hardware Trojans, Bitstream-level Trojans, Bitstream Verification}}, publisher = {{ Paderborn University, Paderborn, Germany}}, title = {{{Hardware Trojans in Reconfigurable Computing}}}, doi = {{10.17619/UNIPB/1-1271}}, year = {{2022}}, } @article{34200, abstract = {{Praxeologische Kompetenzansätze verstehen Kompetenz als sozial erlernt und folglich als relativ zum sozialen Kontext. Damit einher geht die Frage, wie solche praxeologisch gerahmten Kompetenzen eigentlich unabhängig von der sie hervorbringenden Praxis evaluiert werden können – und eben dadurch erst für einen breiteren Kompetenzdiskurs fruchtbar sind. Die Dokumentarische Evaluationsforschung bietet hierzu erste Anhaltspunkte, offenbart aber auch Grenzen, die mit dem Evaluationsverständnis zusammenhängen, sich jedoch in der Forschungspraxis so nicht finden lassen. Aus der Differenz zwischen Methode und Praxis dokumentarischer Evaluation lässt sich formulieren, wie eine praxeologische Evaluation gestaltet werden könnte. Dabei spielt die Formulierung von Referenzrahmen eine zentrale Rolle, welche einerseits der zu evaluierenden Praktik external sein, andererseits praktisch formuliert werden müssen, damit sie soziale Praktiken jenseits ihrer eigenen Sinnhaftigkeit evaluativ (er-)fassen können.}}, author = {{Bloh, Thiemo}}, issn = {{1619-5515}}, journal = {{Zeitschrift für Evaluation}}, keywords = {{Strategy and Management, Applied Psychology, Social Sciences (miscellaneous), Education, Communication, Statistics and Probability}}, number = {{02}}, pages = {{193--215}}, publisher = {{Waxmann}}, title = {{{Rekonstruktive Evaluationsforschung im Kontext praxeologischer Kompetenzdiskurse. Kritische Reflexionen und konzeptionelle Überlegungen zur Dokumentarischen Evaluationsforschung}}}, doi = {{10.31244/zfe.2022.02.02}}, volume = {{2022}}, year = {{2022}}, } @article{34198, author = {{Bloh, Thiemo and Caruso, Carina}}, journal = {{die hochschullehre}}, title = {{{Ein kritisch-multiperspektivischer Blick auf Forschendes Lernen in der Lehrkräftebildung. Fragen, Erwägungen und Rekonstruktionen.}}}, doi = {{10.3278/HSL2221W}}, volume = {{8}}, year = {{2022}}, } @article{34199, author = {{Bloh, Thiemo}}, journal = {{Zeitschrift für Pädagogik}}, number = {{6}}, pages = {{749--762}}, title = {{{Grundlagentheoretische Differenzen in der Lehrkräftekooperationsforschung}}}, doi = {{10.3262/ZP2206749}}, volume = {{68}}, year = {{2022}}, } @inproceedings{34203, author = {{Bloh, Thiemo}}, location = {{Paderborn}}, title = {{{Was bedeutet Post-Digitalität? – Universitäre Lehrpraktiken zwischen situativer Anforderung und habitueller Prägung}}}, year = {{2022}}, } @inproceedings{34201, author = {{Bloh, Thiemo}}, location = {{Oldenburg}}, title = {{{AussteigerInnen – Fluchtbewegungen in der LehrerInnenbiographie}}}, year = {{2022}}, } @inproceedings{34202, author = {{Bloh, Thiemo}}, location = {{Frankfurt a.M.}}, title = {{{„Referenzrahmen“ als gewinnbringendes Konstrukt im Kontext Dokumentarischer Evaluationsforschung!?}}}, year = {{2022}}, } @inproceedings{34204, author = {{Bloh, Thiemo}}, location = {{Paderborn}}, title = {{{The Deconstruction of Professionalism}}}, year = {{2022}}, } @book{34450, editor = {{Harmening, Anda-Lisa Martha Josephine Anna and Leinfellner, Stefanie and Meier, Rebecca}}, isbn = {{978-3-534-27585-4}}, pages = {{352}}, publisher = {{wbg Academic}}, title = {{{Wissenstransfer als Aufgabe, Herausforderung und Chance kulturwissenschaftlicher Forschung}}}, volume = {{1}}, year = {{2022}}, } @inbook{34467, author = {{Lütje-Klose , Birgit and Grüter, Sandra and Neumann, Phillip and Weber, Antonia and Goldan, Janka and Gorges, Julia and Wild, Elke}}, booktitle = {{Qualifizierung für Inklusion. Sekundarstufe }}, editor = {{Lutz, Deborah and Becker, Jonas and Buchhaupt, Felix and Katzenbach, Dieter and Strecker, Alicia and Urban, Michael}}, isbn = {{978-3-8309-4514-7}}, pages = {{163--178}}, publisher = {{Waxmann}}, title = {{{Weil wir tatsächlich nicht voneinander wussten, was jeder Einzelne so an verborgenen Schätzen bringt}}}, doi = {{10.31244/9783830995142}}, volume = {{3}}, year = {{2022}}, }