TY - GEN
AU - Mapura Ramirez, Luz Alejandra
AU - Kenig, Eugeny Y.
ID - 46591
TI - Zur Berechnug von flüssigkeitsseitigen Stoffübergagnskoeffizienten für Strukturpackungen
ER -
TY - JOUR
AB - The Koopman operator has become an essential tool for data-driven approximation of dynamical (control) systems in recent years, e.g., via extended dynamic mode decomposition. Despite its popularity, convergence results and, in particular, error bounds are still quite scarce. In this paper, we derive probabilistic bounds for the approximation error and the prediction error depending on the number of training data points; for both ordinary and stochastic differential equations. Moreover, we extend our analysis to nonlinear control-affine systems using either ergodic trajectories or i.i.d.
samples. Here, we exploit the linearity of the Koopman generator to obtain a bilinear system and, thus, circumvent the curse of dimensionality since we do not autonomize the system by augmenting the state by the control inputs. To the
best of our knowledge, this is the first finite-data error analysis in the stochastic and/or control setting. Finally, we demonstrate the effectiveness of the proposed approach by comparing it with state-of-the-art techniques showing its superiority whenever state and control are coupled.
AU - Nüske, Feliks
AU - Peitz, Sebastian
AU - Philipp, Friedrich
AU - Schaller, Manuel
AU - Worthmann, Karl
ID - 23428
JF - Journal of Nonlinear Science
TI - Finite-data error bounds for Koopman-based prediction and control
VL - 33
ER -
TY - GEN
AB - Different conflicting optimization criteria arise naturally in various Deep
Learning scenarios. These can address different main tasks (i.e., in the
setting of Multi-Task Learning), but also main and secondary tasks such as loss
minimization versus sparsity. The usual approach is a simple weighting of the
criteria, which formally only works in the convex setting. In this paper, we
present a Multi-Objective Optimization algorithm using a modified Weighted
Chebyshev scalarization for training Deep Neural Networks (DNNs) with respect
to several tasks. By employing this scalarization technique, the algorithm can
identify all optimal solutions of the original problem while reducing its
complexity to a sequence of single-objective problems. The simplified problems
are then solved using an Augmented Lagrangian method, enabling the use of
popular optimization techniques such as Adam and Stochastic Gradient Descent,
while efficaciously handling constraints. Our work aims to address the
(economical and also ecological) sustainability issue of DNN models, with a
particular focus on Deep Multi-Task models, which are typically designed with a
very large number of weights to perform equally well on multiple tasks. Through
experiments conducted on two Machine Learning datasets, we demonstrate the
possibility of adaptively sparsifying the model during training without
significantly impacting its performance, if we are willing to apply
task-specific adaptations to the network weights. Code is available at
https://github.com/salomonhotegni/MDMTN.
AU - Hotegni, Sedjro Salomon
AU - Peitz, Sebastian
AU - Berkemeier, Manuel Bastian
ID - 46649
T2 - arXiv:2308.12243
TI - Multi-Objective Optimization for Sparse Deep Neural Network Training
ER -
TY - JOUR
AU - Gonchikzhapov, Munko
AU - Kasper, Tina
ID - 46637
JF - Applications in Energy and Combustion Science
KW - Nanoparticle synthesis
KW - Flame spray pyrolysis
KW - SpraySyn burner
KW - Flame structure
KW - Species distribution
KW - Temperature distribution
SN - 2666-352X
TI - Thermal and chemical structure of ethanol and 2-ethylhexanoic acid/ethanol SpraySyn flames
VL - 15
ER -
TY - JOUR
AB - Many problems in science and engineering require an efficient numerical approximation of integrals or solutions to differential equations. For systems with rapidly changing dynamics, an equidistant discretization is often inadvisable as it results in prohibitively large errors or computational effort. To this end, adaptive schemes, such as solvers based on Runge–Kutta pairs, have been developed which adapt the step size based on local error estimations at each step. While the classical schemes apply very generally and are highly efficient on regular systems, they can behave suboptimally when an inefficient step rejection mechanism is triggered by structurally complex systems such as chaotic systems. To overcome these issues, we propose a method to tailor numerical schemes to the problem class at hand. This is achieved by combining simple, classical quadrature rules or ODE solvers with data-driven time-stepping controllers. Compared with learning solution operators to ODEs directly, it generalizes better to unseen initial data as our approach employs classical numerical schemes as base methods. At the same time it can make use of identified structures of a problem class and, therefore, outperforms state-of-the-art adaptive schemes. Several examples demonstrate superior efficiency. Source code is available at https://github.com/lueckem/quadrature-ML.
AU - Dellnitz, Michael
AU - Hüllermeier, Eyke
AU - Lücke, Marvin
AU - Ober-Blöbaum, Sina
AU - Offen, Christian
AU - Peitz, Sebastian
AU - Pfannschmidt, Karlson
ID - 21600
IS - 2
JF - SIAM Journal on Scientific Computing
TI - Efficient time stepping for numerical integration using reinforcement learning
VL - 45
ER -
TY - CHAP
AU - Dahms, Frederik
AU - Homberg, Werner
ID - 46691
SN - 2195-4356
T2 - Lecture Notes in Mechanical Engineering
TI - Analysis and Modelling of the Deformation in the Manufacture of Flange-Contours by the Combined Friction-Spinning and Flow-Forming Process
ER -
TY - CONF
AU - Garnefeld, I.
AU - Böhm, Eva
AU - Hanf, L.
AU - Helm, S.
ID - 46665
T2 - 2023 AMA Summer Academic Conference, San Francisco, CA
TI - Unboxing video effectiveness – Does speech matter?
ER -
TY - CONF
AU - Kessing, K.
AU - Garnefeld, I.
AU - Böhm, Eva
ID - 46666
T2 - EMAC Annual Conference, Odense, Denmark
TI - The dark and bright side of online reviews in manufacturer online shops
ER -
TY - CONF
AU - Hanf, L.
AU - Garnefeld, I.
AU - Böhm, Eva
AU - Helm, S.
ID - 46667
T2 - EMAC Annual Conference, Odense, Denmark
TI - Stimulating engagement with unboxing videos – Does speech matter?
ER -
TY - CONF
AU - Sadeghi-Kohan, Somayeh
AU - Hellebrand, Sybille
AU - Wunderlich, Hans-Joachim
ID - 46739
T2 - 2023 53rd Annual IEEE/IFIP International Conference on Dependable Systems and Networks Workshops (DSN-W)
TI - Low Power Streaming of Sensor Data Using Gray Code-Based Approximate Communication
ER -
TY - CONF
AU - Janzen, Thomas
AU - Wotschel, Philipp
AU - Meier, Jana
AU - Vogelsang, Christoph
ID - 46740
T2 - EARLI 2023
TI - Assessing pre-service EFL teachers’ feedback performance in role-play-based simulations
ER -
TY - JOUR
AU - Zscherp, Mario Fabian
AU - Jentsch, Silas Aurel
AU - Müller, Marius Johannes
AU - Lider, Vitalii
AU - Becker, Celina
AU - Chen, Limei
AU - Littmann, Mario
AU - Meier, Falco
AU - Beyer, Andreas
AU - Hofmann, Detlev Michael
AU - As, Donat Josef
AU - Klar, Peter Jens
AU - Volz, Kerstin
AU - Chatterjee, Sangam
AU - Schörmann, Jörg
ID - 46741
IS - 33
JF - ACS Applied Materials & Interfaces
KW - General Materials Science
SN - 1944-8244
TI - Overcoming the Miscibility Gap of GaN/InN in MBE Growth of Cubic InxGa1–xN
VL - 15
ER -
TY - CONF
AU - Müller, Michelle
AU - Neumann, Jürgen
ID - 33722
T2 - Proceedings of the 55th Hawaii International Conference on System Sciences (HICSS)
TI - Bring me my Meal on your Wheel - An Empirical Analysis of the Impact of Food Delivery Platforms on Local Restaurant Employment
ER -
TY - JOUR
AB - AbstractWorking conditions of knowledge workers have been subject to rapid change recently. Digital nomadism is no longer a phenomenon that relates only to entrepreneurs, freelancers, and gig workers. Corporate employees, too, have begun to uncouple their work from stationary (home) offices and 9-to-5 schedules. However, pursuing a permanent job in a corporate environment is still subject to fundamentally different values than postulated by the original notion of digital nomadism. Therefore, this paper explores the work identity of what is referred to as ‘corporate nomads’. By drawing on identity theory and the results of semi-structured interviews, the paper proposes a conceptualization of the corporate nomad archetype and presents nine salient identity issues of corporate nomads (e.g., holding multiple contradictory identities, the flexibility paradox, or collaboration constraints). By introducing the ‘corporate nomad’ archetype to the Information Systems literature, this article helps to rethink established conceptions of “home office” and socio-spatial configurations of knowledge work.
AU - Marx, Julian
AU - Stieglitz, Stefan
AU - Brünker, Felix
AU - Mirbabaie, Milad
ID - 44143
JF - Business & Information Systems Engineering
KW - Information Systems
SN - 2363-7005
TI - Home (Office) is where your Heart is
ER -
TY - JOUR
AU - Zander, K.K.
AU - Nguyen, D.
AU - Mirbabaie, Milad
AU - Garnett, S.T.
ID - 46487
JF - International Journal of Disaster Risk Reduction
KW - Geology
KW - Safety Research
KW - Geotechnical Engineering and Engineering Geology
KW - Building and Construction
SN - 2212-4209
TI - Aware but not prepared: understanding situational awareness during the century flood in Germany in 2021
VL - 96
ER -
TY - BOOK
AB - In the proposal for our CRC in 2011, we formulated a vision of markets for
IT services that describes an approach to the provision of such services
that was novel at that time and, to a large extent, remains so today:
„Our vision of on-the-fly computing is that of IT services individually and
automatically configured and brought to execution from flexibly combinable
services traded on markets. At the same time, we aim at organizing
markets whose participants maintain a lively market of services through
appropriate entrepreneurial actions.“
Over the last 12 years, we have developed methods and techniques to
address problems critical to the convenient, efficient, and secure use of
on-the-fly computing. Among other things, we have made the description
of services more convenient by allowing natural language input,
increased the quality of configured services through (natural language)
interaction and more efficient configuration processes and analysis
procedures, made the quality of (the products of) providers in the
marketplace transparent through reputation systems, and increased the
resource efficiency of execution through reconfigurable heterogeneous
computing nodes and an integrated treatment of service description and
configuration. We have also developed network infrastructures that have
a high degree of adaptivity, scalability, efficiency, and reliability, and
provide cryptographic guarantees of anonymity and security for market
participants and their products and services.
To demonstrate the pervasiveness of the OTF computing approach, we
have implemented a proof-of-concept for OTF computing that can run
typical scenarios of an OTF market. We illustrated the approach using
a cutting-edge application scenario – automated machine learning (AutoML).
Finally, we have been pushing our work for the perpetuation of
On-The-Fly Computing beyond the SFB and sharing the expertise gained
in the SFB in events with industry partners as well as transfer projects.
This work required a broad spectrum of expertise. Computer scientists
and economists with research interests such as computer networks and
distributed algorithms, security and cryptography, software engineering
and verification, configuration and machine learning, computer engineering
and HPC, microeconomics and game theory, business informatics
and management have successfully collaborated here.
AU - Haake, Claus-Jochen
AU - Meyer auf der Heide, Friedhelm
AU - Platzner, Marco
AU - Wachsmuth, Henning
AU - Wehrheim, Heike
ID - 45863
TI - On-The-Fly Computing -- Individualized IT-services in dynamic markets
VL - 412
ER -
TY - JOUR
AU - Stieglitz, Stefan
AU - Mirbabaie, Milad
AU - Deubel, Annika
AU - Braun, Lea-Marie
AU - Kissmer, Tobias
ID - 45458
JF - International Journal of Information Management
KW - Library and Information Sciences
KW - Computer Networks and Communications
KW - Information Systems
SN - 0268-4012
TI - The potential of digital nudging to bridge the gap between environmental attitude and behavior in the usage of smart home applications
VL - 72
ER -
TY - JOUR
AU - Mirbabaie, Milad
AU - Marx, Julian
AU - Erle, Lukas
ID - 46746
JF - Pacific Asia Journal of the Association for Information Systems
SN - 1943-7544
TI - Digital Nudge Stacking and Backfiring: Understanding Sustainable E-Commerce Purchase Decisions
ER -
TY - DATA
AB - Die Energieaufnahme von Haushaltskältegeräten ist seit den 1990er Jahren erheblich gesunken. Dieser Wert wird von den Herstellern im Neuzustand der Geräte unter Normbedingungen bestimmt. Wie jedes technische System unterliegen jedoch auch Haushaltskältegeräte einem Alterungsprozess, der zu einem Anstieg der Energieaufnahme über die Zeit führt. Im Rahmen dieser Dissertation wurde auf der Grundlage von 100 Messungen der Energieaufnahme, die an 32 Geräten über einen Zeitraum von 21 Jahren durchgeführt wurden, ein Alterungsmodell entwickelt. Dieses Modell ist das erste, das mit Hilfe von Daten der Energieaufnahme real gealterter Geräte entwickelt wurde. Es beschreibt einen Anstieg der Energieaufnahme von 27 % über die durchschnittliche Einsatzzeit eines Haushaltskältegeräts von 16 Jahren. Der stärkste Anstieg erfolgt in den ersten fünf Betriebsjahren. Durch Diffusionsvorgänge in dem im Gehäuse verbauten Polyurethan-Schaum wird das im Zellgas vorhandene Kohlenstoffdioxid durch Luft ersetzt. Hierdurch steigt die Wärmeleitfähigkeit des Schaums um ca. 33 % an, wodurch sich die Energieaufnahme der Geräte erhöht. Des Weiteren wurde der Einsatz von Paraffinen als Phasenwechselmaterial in Haushaltskältegeräten untersucht. Durch deren Einsatz konnte die Energieaufnahme gesenkt und die Funktionalität der Geräte gesteigert werden. Hierfür sind detaillierte Kenntnisse der Materialkenndaten der Paraffine notwendig. Die Wärmeleitfähigkeit der verschiedenen Paraffin-Stoffgruppen in der festen Phase ist jedoch bisher nur unzureichend untersucht worden. Daher wurde ein Messaufbau entwickelt, mit dem die Wärmeleitfähigkeit von festem Paraffin bestimmt werden kann, und es wurden entsprechende Messungen durchgeführt.
AU - Paul, Andreas
ID - 46753
TI - Analyse von Alterungsmechanismen im Hinblick auf die Effizienz von Haushaltskältegeräten
ER -
TY - JOUR
AB - Qualitative comparative analysis (QCA) enables researchers in international management to better understand how the impact of a single explanatory factor depends on the context of other factors. But the analytical toolbox of QCA does not include a parameter for the explanatory power of a single explanatory factor or “condition”. In this paper, we therefore reinterpret the Banzhaf power index, originally developed in cooperative game theory, to establish a goodness-of-fit parameter in QCA. The relative Banzhaf index we suggest measures the explanatory power of one condition averaged across all sufficient combinations of conditions. The paper argues that the index is especially informative in three situations that are all salient in international management and call for a context-sensitive analysis of single conditions, namely substantial limited diversity in the data, the emergence of strong INUS conditions in the analysis, and theorizing with contingency factors. The paper derives the properties of the relative Banzhaf index in QCA, demonstrates how the index can be computed easily from a rudimentary truth table, and explores its insights by revisiting selected papers in international management that apply fuzzy-set QCA. It finally suggests a three-step procedure for utilizing the relative Banzhaf index when the causal structure involves both contingency effects and configurational causation.
AU - Haake, Claus-Jochen
AU - Schneider, Martin
ID - 34114
JF - Journal of International Management
KW - Qualitative comparative analysis
KW - Banzhaf power index
KW - causality
KW - explanatory power
TI - Playing games with QCA: Measuring the explanatory power of single conditions with the Banzhaf index
ER -