TY - GEN
ED - Troschitz, Juliane
ED - Vorderbrüggen, Julian
ED - Kupfer, Robert
ED - Gude, Maik
ED - Meschut, Gerson
ID - 20119
T2 - Applied Sciences
TI - Joining of Thermoplastic Composites with Metals Using Resistance Element Welding
ER -
TY - BOOK
AU - Schneider, Martin
AU - Sadowski, Dieter
AU - Frick, Bernd
AU - Warning, Susanne
ID - 21566
TI - Personalökonomie und Personalpolitik: Grundlagen einer evidenzbasierten Praxis
ER -
TY - JOUR
AB - Many basic properties in Tutte's flow theory for unsigned graphs do not have
their counterparts for signed graphs. However, signed graphs without long
barbells in many ways behave like unsigned graphs from the point view of flows.
In this paper, we study whether some basic properties in Tutte's flow theory
remain valid for this family of signed graphs. Specifically let $(G,\sigma)$ be
a flow-admissible signed graph without long barbells. We show that it admits a
nowhere-zero $6$-flow and that it admits a nowhere-zero modulo $k$-flow if and
only if it admits a nowhere-zero integer $k$-flow for each integer $k\geq 3$
and $k \not = 4$. We also show that each nowhere-zero positive integer $k$-flow
of $(G,\sigma)$ can be expressed as the sum of some $2$-flows. For general
graphs, we show that every nowhere-zero $\frac{p}{q}$-flow can be normalized in
such a way, that each flow value is a multiple of $\frac{1}{2q}$. As a
consequence we prove the equality of the integer flow number and the ceiling of
the circular flow number for flow-admissible signed graphs without long
barbells.
AU - Lu, You
AU - Luo, Rong
AU - Schubert, Michael
AU - Steffen, Eckhard
AU - Zhang, Cun-Quan
ID - 13114
JF - SIAM J. Discrete Math
TI - Flows on signed graphs without long barbells
VL - 34 (4)
ER -
TY - JOUR
AB - We derive a data-driven method for the approximation of the Koopman generator called gEDMD, which can be regarded as a straightforward extension of EDMD (extended dynamic mode decomposition). This approach is applicable to deterministic and stochastic dynamical systems. It can be used for computing eigenvalues, eigenfunctions, and modes of the generator and for system identification. In addition to learning the governing equations of deterministic systems, which then reduces to SINDy (sparse identification of nonlinear dynamics), it is possible to identify the drift and diffusion terms of stochastic differential equations from data. Moreover, we apply gEDMD to derive coarse-grained models of high-dimensional systems, and also to determine efficient model predictive control strategies. We highlight relationships with other methods and demonstrate the efficacy of the proposed methods using several guiding examples and prototypical molecular dynamics problems.
AU - Klus, Stefan
AU - Nüske, Feliks
AU - Peitz, Sebastian
AU - Niemann, Jan-Hendrik
AU - Clementi, Cecilia
AU - Schütte, Christof
ID - 16288
JF - Physica D: Nonlinear Phenomena
SN - 0167-2789
TI - Data-driven approximation of the Koopman generator: Model reduction, system identification, and control
VL - 406
ER -
TY - CHAP
AU - Matz, Frauke
AU - Rumlich, Dominik
ED - Grünewald, Andreas
ED - Hethey, Meike
ED - Struve, Karen
ID - 21915
T2 - KONTROVERS. Literaturdidaktik meets Literaturwissenschaft
TI - Englischsprachige Jugendbücher innerhalb und außerhalb des Englischunterrichts – Young Adult Fiction als empirischer Gegenstand der Literaturdidaktik
ER -
TY - JOUR
AB - Many dimensionality and model reduction techniques rely on estimating dominant eigenfunctions of associated dynamical operators from data. Important examples include the Koopman operator and its generator, but also the Schrödinger operator. We propose a kernel-based method for the approximation of differential operators in reproducing kernel Hilbert spaces and show how eigenfunctions can be estimated by solving auxiliary matrix eigenvalue problems. The resulting algorithms are applied to molecular dynamics and quantum chemistry examples. Furthermore, we exploit that, under certain conditions, the Schrödinger operator can be transformed into a Kolmogorov backward operator corresponding to a drift-diffusion process and vice versa. This allows us to apply methods developed for the analysis of high-dimensional stochastic differential equations to quantum mechanical systems.
AU - Klus, Stefan
AU - Nüske, Feliks
AU - Hamzi, Boumediene
ID - 21819
JF - Entropy
SN - 1099-4300
TI - Kernel-Based Approximation of the Koopman Generator and Schrödinger Operator
ER -
TY - JOUR
AU - Bürger, Julius
AU - Riedl, Thomas
AU - Lindner, Jörg K.N.
ID - 20892
JF - Ultramicroscopy
SN - 0304-3991
TI - Influence of lens aberrations, specimen thickness and tilt on differential phase contrast STEM images
ER -
TY - JOUR
AU - Li, Jie
AU - Ji, Chendong
AU - Lü, Baozhong
AU - Rodin, Maksim
AU - Paradies, Jan
AU - Yin, Meizhen
AU - Kuckling, Dirk
ID - 22235
JF - ACS Applied Materials & Interfaces
SN - 1944-8244
TI - Dually Crosslinked Supramolecular Hydrogel for Cancer Biomarker Sensing
ER -
TY - CONF
AU - Krüger, Christopher
AU - Schmolke, Tobias
AU - Merdivan, David
AU - Spohr, Sebastian
AU - Urban, Peter
AU - Meschut, Gerson
ID - 20316
TI - Concept Development for a Functional Integrated Lightweight Battery Housing with Special Consideration of the Joining Technology
ER -
TY - JOUR
AU - Grabo, Matti
AU - Staggenborg, Christoph
AU - Philippi, Kai Alexander
AU - Kenig, Eugeny
ID - 22266
JF - Frontiers in Energy Research
SN - 2296-598X
TI - Modeling and Optimization of Rectangular Latent Heat Storage Elements in an Air-Guided Heat Storage System
VL - 8
ER -