TY - CONF
AB - We propose a reachability approach for infinite and finite horizon multi-objective optimization problems for low-thrust spacecraft trajectory design. The main advantage of the proposed method is that the Pareto front can be efficiently constructed from the zero level set of the solution to a Hamilton-Jacobi-Bellman equation. We demonstrate the proposed method by applying it to a low-thrust spacecraft trajectory design problem. By deriving the analytic expression for the Hamiltonian and the optimal control policy, we are able to efficiently compute the backward reachable set and reconstruct the optimal trajectories. Furthermore, we show that any reconstructed trajectory will be guaranteed to be weakly Pareto optimal. The proposed method can be used as a benchmark for future research of applying reachability analysis to low-thrust spacecraft trajectory design.
AU - Vertovec, Nikolaus
AU - Ober-Blöbaum, Sina
AU - Margellos, Kostas
ID - 21592
TI - Multi-objective minimum time optimal control for low-thrust trajectory design
ER -
TY - JOUR
AU - Holzinger, Philipp
AU - Bodden, Eric
ID - 21597
JF - International Symposium on Advanced Security on Software and Systems (ASSS)
TI - A Systematic Hardening of Java's Information Hiding
ER -
TY - JOUR
AU - Lienen, Julian
AU - Hüllermeier, Eyke
ID - 21636
JF - International Journal of Approximate Reasoning
TI - Instance weighting through data imprecisiation
ER -
TY - GEN
AB - Many problems in science and engineering require the efficient numerical
approximation of integrals, a particularly important application being the
numerical solution of initial value problems for differential equations. For
complex systems, an equidistant discretization is often inadvisable, as it
either results in prohibitively large errors or computational effort. To this
end, adaptive schemes have been developed that rely on error estimators based
on Taylor series expansions. While these estimators a) rely on strong
smoothness assumptions and b) may still result in erroneous steps for complex
systems (and thus require step rejection mechanisms), we here propose a
data-driven time stepping scheme based on machine learning, and more
specifically on reinforcement learning (RL) and meta-learning. First, one or
several (in the case of non-smooth or hybrid systems) base learners are trained
using RL. Then, a meta-learner is trained which (depending on the system state)
selects the base learner that appears to be optimal for the current situation.
Several examples including both smooth and non-smooth problems demonstrate the
superior performance of our approach over state-of-the-art numerical schemes.
The code is available under 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
T2 - arXiv:2104.03562
TI - Efficient time stepping for numerical integration using reinforcement learning
ER -
TY - JOUR
AU - Penner, Eduard
AU - Caylak, Ismail
AU - Mahnken, Rolf
AU - Dridger, Alex
ID - 21681
JF - Safety and Reliability
SN - 0961-7353
TI - Fuzzy and stochastic approach applied to rubber like materials
ER -
TY - GEN
AB - We push the boundaries of electronic structure-based ab-initio
molecular dynamics (AIMD) beyond 100 million atoms. This scale is otherwise
barely reachable with classical force-field methods or novel neural network and
machine learning potentials. We achieve this breakthrough by combining
innovations in linear-scaling AIMD, efficient and approximate sparse linear
algebra, low and mixed-precision floating-point computation on GPUs, and a
compensation scheme for the errors introduced by numerical approximations.
The core of our work is the non-orthogonalized local submatrix (NOLSM)
method, which scales very favorably to massively parallel computing systems and
translates large sparse matrix operations into highly parallel, dense matrix
operations that are ideally suited to hardware accelerators. We demonstrate
that the NOLSM method, which is at the center point of each AIMD step, is able
to achieve a sustained performance of 324 PFLOP/s in mixed FP16/FP32 precision
corresponding to an efficiency of 67.7% when running on 1536 NVIDIA A100 GPUs.
AU - Schade, Robert
AU - Kenter, Tobias
AU - Elgabarty, Hossam
AU - Lass, Michael
AU - Schütt, Ole
AU - Lazzaro, Alfio
AU - Pabst, Hans
AU - Mohr, Stephan
AU - Hutter, Jürg
AU - Kühne, Thomas
AU - Plessl, Christian
ID - 21732
TI - Enabling Electronic Structure-Based Ab-Initio Molecular Dynamics Simulations with Hundreds of Millions of Atoms
ER -
TY - CONF
AU - Sander, Sascha
AU - Teutenberg, Dominik
AU - Meschut, Gerson
AU - Matzenmiller, Anton
ID - 21802
T2 - 21. Kolloquium Gemeinsame Forschung in der Klebtechnik
TI - Methodenentwicklung zur Langzeitprognose von Klebverbindungen bei kombinierter Temperatur- und Medieneinwirkung
ER -
TY - JOUR
AU - Gröger, Benjamin
AU - Troschitz, Juliane
AU - Vorderbrüggen, Julian
AU - Vogel, Christian
AU - Kupfer, Robert
AU - Meschut, Gerson
AU - Gude, Maik
ID - 21814
JF - Materials
TI - Clinching of Thermoplastic Composites and Metals—A Comparison of Three Novel Joining Technologies
ER -
TY - CHAP
AU - Tönnies, Merle
ED - Tönnies, Merle
ED - Schlieper, Hendrick
ID - 21826
T2 - Gattung und Geschlecht: Konventionen und Transformationen eines Paradigmas
TI - The Black British Bildungsroman: Gender-specific Plot Models?
VL - 21
ER -
TY - JOUR
AU - Rumlich, Dominik
ID - 21927
IS - 1
JF - Journal of Immersion and Content-Based Language Education
SN - 2212-8433
TI - Review of Liss Kerstin Sylvén (Ed.). (2019). Investigating content and language integrated learning. Insights from Swedish high schools
VL - 9
ER -
TY - CONF
AU - Fischer, Elena
AU - Schmolke, Tobias
AU - Chudalla, Nick
AU - Teutenberg, Dominik
AU - Meschut, Gerson
ID - 21718
TI - Auslegungsmethode für Klebverbindungen mit KTL-beschichteten Fügeteilen und polymeren, faserverstärkten Werkstoffen – Kleben auf KTL
ER -
TY - JOUR
AU - Albert, M.
AU - Golla, C.
AU - Meier, Cedrik
ID - 20900
JF - Journal of Crystal Growth
SN - 0022-0248
TI - Optical in-situ temperature management for high-quality ZnO molecular beam epitaxy
VL - 557
ER -
TY - JOUR
AB - Three-dimensional modelling enables to determine the in-plane material flow in asymmetrical situation. Thus, the distortion of the sheets to be joined can be characterized more exactly. This study shows a method for building up a three-dimensional shear-clinching framework without damage criteria. In fact, the die-sided sheet in shear-clinching was designed as a pre-punched sheet and slugs. The material separation in the die-sided joining partner, which in two-dimensional simulation is often described by macro- and micromechanical fracture criteria, was realised in this study based on a defined contact condition. By means of a shear-cutting simulation, a correlation between the break angle and the separation stress was determined, which was used as a separation criterion in the shear-clinching simulation. The separation line was confirmed using post-particles. To validate this model, the results of the simulation using a quadratic single-point specimen were compared to the experiments with respect to the distortion of the joining partner. In general, the built three-dimensional framework provides for further tool developments with regard to the reduction of distortion in shear-clinching.
AU - Han, Daxin
AU - Yang, Chen
AU - Meschut, Gerson
ID - 21679
JF - ESAFORM 2021
TI - A method for three-dimensional modelling of the shear-clinching process
ER -
TY - CHAP
AB - We construct more efficient cryptosystems with provable
security against adaptive attacks, based on simple and natural hardness
assumptions in the standard model. Concretely, we describe:
– An adaptively-secure variant of the efficient, selectively-secure LWE-
based identity-based encryption (IBE) scheme of Agrawal, Boneh,
and Boyen (EUROCRYPT 2010). In comparison to the previously
most efficient such scheme by Yamada (CRYPTO 2017) we achieve
smaller lattice parameters and shorter public keys of size O(log λ),
where λ is the security parameter.
– Adaptively-secure variants of two efficient selectively-secure pairing-
based IBEs of Boneh and Boyen (EUROCRYPT 2004). One is based
on the DBDH assumption, has the same ciphertext size as the cor-
responding BB04 scheme, and achieves full adaptive security with
public parameters of size only O(log λ). The other is based on a q-
type assumption and has public key size O(λ), but a ciphertext is
only a single group element and the security reduction is quadrat-
ically tighter than the corresponding scheme by Jager and Kurek
(ASIACRYPT 2018).
– A very efficient adaptively-secure verifiable random function where
proofs, public keys, and secret keys have size O(log λ).
As a technical contribution we introduce blockwise partitioning, which
leverages the assumption that a cryptographic hash function is weak
near-collision resistant to prove full adaptive security of cryptosystems.
AU - Jager, Tibor
AU - Kurek, Rafael
AU - Niehues, David
ID - 22057
SN - 0302-9743
T2 - Public-Key Cryptography – PKC 2021
TI - Efficient Adaptively-Secure IB-KEMs and VRFs via Near-Collision Resistance
ER -
TY - GEN
AU - Lorenz, Johannes
AU - Sureth-Sloane, Caren
AU - Diller, Markus
ID - 22211
TI - Inconsistent tax transfer prices: tax filings, audits, and double taxation
ER -
TY - CONF
AU - Witschen, Linus Matthias
AU - Wiersema, Tobias
AU - Raeisi Nafchi, Masood
AU - Bockhorn, Arne
AU - Platzner, Marco
ED - Hannig, Frank
ED - Derrien, Steven
ED - Diniz, Pedro
ED - Chillet, Daniel
ID - 21953
T2 - Proceedings of International Symposium on Applied Reconfigurable Computing (ARC'21)
TI - Timing Optimization for Virtual FPGA Configurations
ER -
TY - GEN
AU - Rehnen, Jakob Werner
ID - 22216
TI - Decomposition of Arithmetic Components for the Approximate Circuit Synthesis with EvoApproxLib
ER -
TY - JOUR
AB - It is a challenging task to identify the objectives on which a certain decision was based, in particular if several, potentially conflicting criteria are equally important and a continuous set of optimal compromise decisions exists. This task can be understood as the inverse problem of multiobjective optimization, where the goal is to find the objective function vector of a given Pareto set. To this end, we present a method to construct the objective function vector of an unconstrained multiobjective optimization problem (MOP) such that the Pareto critical set contains a given set of data points with prescribed KKT multipliers. If such an MOP can not be found, then the method instead produces an MOP whose Pareto critical set is at least close to the data points. The key idea is to consider the objective function vector in the multiobjective KKT conditions as variable and then search for the objectives that minimize the Euclidean norm of the resulting system of equations. By expressing the objectives in a finite-dimensional basis, we transform this problem into a homogeneous, linear system of equations that can be solved efficiently. Potential applications of this approach include the identification of objectives (both from clean and noisy data) and the construction of surrogate models for expensive MOPs.
AU - Gebken, Bennet
AU - Peitz, Sebastian
ID - 16295
JF - Journal of Global Optimization
TI - Inverse multiobjective optimization: Inferring decision criteria from data
VL - 80
ER -
TY - JOUR
AU - Roman-Rodriguez, V
AU - Brecht, B
AU - Srinivasan, K
AU - Silberhorn, C
AU - Treps, N
AU - Diamanti, E
AU - Parigi, V
ID - 22259
JF - New Journal of Physics
SN - 1367-2630
TI - Continuous variable multimode quantum states via symmetric group velocity matching
VL - 23
ER -
TY - CONF
AU - Lienen, Julian
AU - Hüllermeier, Eyke
AU - Ewerth, Ralph
AU - Nommensen, Nils
ID - 22280
T2 - Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, CVPR
TI - Monocular Depth Estimation via Listwise Ranking using the Plackett-Luce Model
ER -