@article{13348, author = {{Luk, Samuel M. H. and Lewandowski, P. and Kwong, N. H. and Baudin, E. and Lafont, O. and Tignon, J. and Leung, P. T. and Chan, Ch. K. P. and Babilon, M. and Schumacher, Stefan and Binder, R.}}, issn = {{0740-3224}}, journal = {{Journal of the Optical Society of America B}}, number = {{1}}, title = {{{Theory of optically controlled anisotropic polariton transport in semiconductor double microcavities}}}, doi = {{10.1364/josab.35.000146}}, volume = {{35}}, year = {{2018}}, } @article{13351, author = {{Breddermann, Dominik and Praschan, Tom and Heinze, Dirk Florian and Binder, Rolf and Schumacher, Stefan}}, issn = {{2469-9950}}, journal = {{Physical Review B}}, number = {{12}}, title = {{{Microscopic theory of cavity-enhanced single-photon emission from optical two-photon Raman processes}}}, doi = {{10.1103/physrevb.97.125303}}, volume = {{97}}, year = {{2018}}, } @article{17065, author = {{Esser, Norbert and Schmidt, Wolf Gero}}, issn = {{0370-1972}}, journal = {{physica status solidi (b)}}, number = {{256}}, title = {{{Electric Field Induced Raman Scattering at the Sb–InP(110) Interface: The Surface Dipole Contribution}}}, doi = {{10.1002/pssb.201800314}}, year = {{2018}}, } @inbook{3836, abstract = {{We apply the Discontinuous Galerkin Time Domain (DGTD) method for numerical simulations of the second harmonic generation from various metallic nanostructures. A Maxwell–Vlasov hydrodynamic model is used to describe the nonlinear effects in the motion of the excited free electrons in a metal. The results are compared with the corresponding experimental measurements for split-ring resonators and plasmonic gap antennas.}}, author = {{Grynko, Yevgen and Förstner, Jens}}, booktitle = {{Recent Trends in Computational Photonics}}, editor = {{Agrawal, Arti}}, isbn = {{9783319554372}}, issn = {{0342-4111}}, keywords = {{tet_topic_numerics, tet_topic_shg, tet_topic_meta}}, pages = {{261--284}}, publisher = {{Springer International Publishing}}, title = {{{Simulation of Second Harmonic Generation from Photonic Nanostructures Using the Discontinuous Galerkin Time Domain Method}}}, doi = {{10.1007/978-3-319-55438-9_9}}, year = {{2017}}, } @misc{1157, author = {{Witschen, Linus Matthias}}, publisher = {{Universität Paderborn}}, title = {{{A Framework for the Synthesis of Approximate Circuits}}}, year = {{2017}}, } @article{23966, author = {{Piper, M. and Zibart, A. and Kenig, E.Y.}}, issn = {{1290-0729}}, journal = {{International Journal of Thermal Sciences}}, pages = {{459--468}}, title = {{{New design equations for turbulent forced convection heat transfer and pressure loss in pillow-plate channels}}}, doi = {{10.1016/j.ijthermalsci.2017.06.012}}, year = {{2017}}, } @inproceedings{23970, author = {{Zibart, Alexander and Kenig, Eugeny}}, location = {{Dubrovnik, Croatia}}, title = {{{Numerical Investigation of Liquid Falling Film Flow on the Wavy Surface of Vertical Pillow Plates}}}, year = {{2017}}, } @inproceedings{5914, abstract = {{During the last years, alternative drive technologies, for example electrically powered vehicles (EV), have gained more and more attention, mainly caused by an increasing awareness of the impact of CO2 emissions on climate change and by the limitation of fossil fuels. However, these technologies currently come with new challenges due to limited lithium ion battery storage density and high battery costs which lead to a considerably reduced range in comparison to conventional internal combustion engine powered vehicles. For this reason, it is desirable to increase the vehicle range without enlarging the battery. When the route and the road slope are known in advance, it is possible to vary the vehicles velocity within certain limits in order to reduce the overall drivetrain energy consumption. This may either result in an increased range or, alternatively, in larger energy reserves for comfort functions such as air conditioning. In this presentation, we formulate the challenge of range extension as a multiobjective optimal control problem. We then apply different numerical methods to calculate the so-called Pareto set of optimal compromises for the drivetrain power profile with respect to the two concurrent objectives battery state of charge and mean velocity. In order to numerically solve the optimal control problem by means of a direct method, a time discretization of the drivetrain power profile is necessary. In combination with a vehicle dynamics simulation model, the optimal control problem is transformed into a high dimensional nonlinear optimization problem. For the approximation of the Pareto set, two different optimization algorithms implemented in the software package GAIO are used. The first one yields a global optimal solution by applying a set-oriented subdivision technique to parameter space. By construction, this technique is limited to coarse discretizations of the drivetrain power profile. In contrast, the second technique, which is based on an image space continuation method, is more suitable when the number of parameters is large while the number of objectives is less than five. We compare the solutions of the two algorithms and study the influence of different discretizations on the quality of the solutions. A MATLAB/Simulink model is used to describe the dynamics of an EV. It is based on a drivetrain efficiency map and considers vehicle properties such as rolling friction and air drag, as well as environmental conditions like slope and ambient temperature. The vehicle model takes into account the traction battery too, enabling an exact prediction of the batterys response to power requests of drivetrain and auxiliary loads, including state of charge.}}, author = {{Dellnitz, Michael and Eckstein, Julian and Flaßkamp, Kathrin and Friedel, Patrick and Horenkamp, Christian and Köhler, Ulrich and Ober-Blöbaum, Sina and Peitz, Sebastian and Tiemeyer, Sebastian}}, booktitle = {{Progress in Industrial Mathematics at ECMI 2014 }}, isbn = {{9783319234120}}, issn = {{1612-3956}}, pages = {{633--641}}, publisher = {{Springer International Publishing}}, title = {{{Multiobjective Optimal Control Methods for the Development of an Intelligent Cruise Control}}}, doi = {{10.1007/978-3-319-23413-7_87}}, year = {{2017}}, } @inproceedings{8752, abstract = {{In this article we develop a gradient-based algorithm for the solution of multiobjective optimization problems with uncertainties. To this end, an additional condition is derived for the descent direction in order to account for inaccuracies in the gradients and then incorporated into a subdivision algorithm for the computation of global solutions to multiobjective optimization problems. Convergence to a superset of the Pareto set is proved and an upper bound for the maximal distance to the set of substationary points is given. Besides the applicability to problems with uncertainties, the algorithm is developed with the intention to use it in combination with model order reduction techniques in order to efficiently solve PDE-constrained multiobjective optimization problems.}}, author = {{Peitz, Sebastian and Dellnitz, Michael}}, booktitle = {{NEO 2016}}, isbn = {{9783319640624}}, issn = {{1860-949X}}, pages = {{159--182}}, title = {{{Gradient-Based Multiobjective Optimization with Uncertainties}}}, doi = {{10.1007/978-3-319-64063-1_7}}, year = {{2017}}, } @article{6552, author = {{Bause, Fabian and Claes, Leander and Webersen, Manuel and Johannesmann, Sarah and Henning, Bernd}}, issn = {{0171-8096}}, journal = {{tm - Technisches Messen}}, number = {{3}}, title = {{{Viskoelastizität und Anisotropie von Kunststoffen: Ultraschallbasierte Methoden zur Materialparameterbestimmung}}}, doi = {{10.1515/teme-2016-0056}}, volume = {{84}}, year = {{2017}}, } @inproceedings{6575, author = {{Bause, Fabian and Claes, Leander and Webersen, Manuel and Henning, Bernd}}, booktitle = {{PROCEEDINGS -- AMA Conferences 2017}}, isbn = {{978-3-9816876-4-4}}, pages = {{414}}, title = {{{Ultrasonic measurements in the characterization of viscoelasticity and aging of polymers}}}, doi = {{10.5162/sensor2017/C8.1}}, year = {{2017}}, } @misc{6591, author = {{Claes, Leander and Feldmann, Nadine and Henning, Bernd}}, title = {{{Spektrale Verfahren zur Bestimmung der akustischen Absorption in fluiden Medien}}}, year = {{2017}}, } @article{68, abstract = {{Proof-carrying hardware (PCH) is a principle for achieving safety for dynamically reconfigurable hardware systems. The producer of a hardware module spends huge effort when creating a proof for a safety policy. The proof is then transferred as a certificate together with the configuration bitstream to the consumer of the hardware module, who can quickly verify the given proof. Previous work utilized SAT solvers and resolution traces to set up a PCH technology and corresponding tool flows. In this article, we present a novel technology for PCH based on inductive invariants. For sequential circuits, our approach is fundamentally stronger than the previous SAT-based one since we avoid the limitations of bounded unrolling. We contrast our technology to existing ones and show that it fits into previously proposed tool flows. We conduct experiments with four categories of benchmark circuits and report consumer and producer runtime and peak memory consumption, as well as the size of the certificates and the distribution of the workload between producer and consumer. Experiments clearly show that our new induction-based technology is superior for sequential circuits, whereas the previous SAT-based technology is the better choice for combinational circuits.}}, author = {{Isenberg, Tobias and Platzner, Marco and Wehrheim, Heike and Wiersema, Tobias}}, journal = {{ACM Transactions on Design Automation of Electronic Systems}}, number = {{4}}, pages = {{61:1----61:23}}, publisher = {{ACM}}, title = {{{Proof-Carrying Hardware via Inductive Invariants}}}, doi = {{10.1145/3054743}}, year = {{2017}}, } @phdthesis{10594, abstract = {{Multiobjective optimization plays an increasingly important role in modern applications, where several criteria are often of equal importance. The task in multiobjective optimization and multiobjective optimal control is therefore to compute the set of optimal compromises (the Pareto set) between the conflicting objectives. Since – in contrast to the solution of a single objective optimization problem – the Pareto set generally consists of an infinite number of solutions, the computational effort can quickly become challenging. This is even more the case when many problems have to be solved, when the number of objectives is high, or when the objectives are costly to evaluate. Consequently, this thesis is devoted to the identification and exploitation of structure both in the Pareto set and the dynamics of the underlying model as well as to the development of efficient algorithms for solving problems with additional parameters, with a high number of objectives or with PDE-constraints. These three challenges are addressed in three respective parts. In the first part, predictor-corrector methods are extended to entire Pareto sets. When certain smoothness assumptions are satisfied, then the set of parameter dependent Pareto sets possesses additional structure, i.e. it is a manifold. The tangent space can be approximated numerically which yields a direction for the predictor step. In the corrector step, the predicted set converges to the Pareto set at a new parameter value. The resulting algorithm is applied to an example from autonomous driving. In the second part, the hierarchical structure of Pareto sets is investigated. When considering a subset of the objectives, the resulting solution is a subset of the Pareto set of the original problem. Under additional smoothness assumptions, the respective subsets are located on the boundary of the Pareto set of the full problem. This way, the “skeleton” of a Pareto set can be computed and due to the exponential increase in computing time with the number of objectives, the computations of these subsets are significantly faster which is demonstrated using an example from industrial laundries. In the third part, PDE-constrained multiobjective optimal control problems are addressed by reduced order modeling methods. Reduced order models exploit the structure in the system dynamics, for example by describing the dynamics of only the most energetic modes. The model reduction introduces an error in both the function values and their gradients, which has to be taken into account in the development of algorithms. Both scalarization and set-oriented approaches are coupled with reduced order modeling. Convergence results are presented and the numerical benefit is investigated. The algorithms are applied to semi-linear heat flow problems as well as to the Navier-Stokes equations. }}, author = {{Peitz, Sebastian}}, title = {{{ Exploiting structure in multiobjective optimization and optimal control}}}, doi = {{10.17619/UNIPB/1-176}}, year = {{2017}}, } @inproceedings{11809, abstract = {{This paper presents an end-to-end training approach for a beamformer-supported multi-channel ASR system. A neural network which estimates masks for a statistically optimum beamformer is jointly trained with a network for acoustic modeling. To update its parameters, we propagate the gradients from the acoustic model all the way through feature extraction and the complex valued beamforming operation. Besides avoiding a mismatch between the front-end and the back-end, this approach also eliminates the need for stereo data, i.e., the parallel availability of clean and noisy versions of the signals. Instead, it can be trained with real noisy multichannel data only. Also, relying on the signal statistics for beamforming, the approach makes no assumptions on the configuration of the microphone array. We further observe a performance gain through joint training in terms of word error rate in an evaluation of the system on the CHiME 4 dataset.}}, author = {{Heymann, Jahn and Drude, Lukas and Boeddeker, Christoph and Hanebrink, Patrick and Haeb-Umbach, Reinhold}}, booktitle = {{Proc. IEEE Intl. Conf. on Acoustics, Speech and Signal Processing (ICASSP)}}, title = {{{BEAMNET: End-to-End Training of a Beamformer-Supported Multi-Channel ASR System}}}, year = {{2017}}, } @article{15941, author = {{Reuter, Corin and Sauerland, Kim-Henning and Tröster, Thomas}}, issn = {{0263-8223}}, journal = {{Composite Structures}}, pages = {{33--44}}, title = {{{Experimental and numerical crushing analysis of circular CFRP tubes under axial impact loading}}}, doi = {{10.1016/j.compstruct.2017.04.052}}, year = {{2017}}, } @article{15942, author = {{Reuter, Corin and Tröster, Thomas}}, issn = {{0263-8231}}, journal = {{Thin-Walled Structures}}, pages = {{1--9}}, title = {{{Crashworthiness and numerical simulation of hybrid aluminium-CFRP tubes under axial impact}}}, doi = {{10.1016/j.tws.2017.03.034}}, volume = {{117}}, year = {{2017}}, } @article{15944, author = {{Striewe, Jan André and Reuter, Corin and Sauerland, Kim-Henning and Tröster, Thomas}}, issn = {{0263-8231}}, journal = {{Thin-Walled Structures}}, pages = {{501--508}}, title = {{{Manufacturing and crashworthiness of fabric-reinforced thermoplastic composites}}}, doi = {{10.1016/j.tws.2017.11.011}}, year = {{2017}}, } @phdthesis{16332, author = {{Stührenberg, Kai}}, title = {{{Phenanthroline-basierte Kupferkomplexe für Wasserspaltungsanwendungen}}}, doi = {{10.17619/UNIPB/1-253}}, year = {{2017}}, } @inproceedings{13156, abstract = {{Liner carriers change their network on a regular basis, and they are therefore interested in a practical evaluation of the impact these changes have on the cargo flows in their networks. Despite great advancements in the practical applicability of network evaluators in recent years, vessel deployment continues to be considered as an input into the problem, rather than a decision. In this paper, we propose an extension of a state-of-the-art mixed integer programming model for the LSCAP that incorporates the optimization of vessel count and vessel classes for each service. We perform a computational analysis on liner shipping networks of different sizes and compare our optimized results to fixed deployment scenarios. By integrating fleet deployment decisions into the cargo allocation problem, liner carriers can increase the profitability of their networks by at least 2.8 to 16.9{\%} and greatly enhance their decision making.}}, author = {{Müller, Daniel and Guericke, Stefan and Tierney, Kevin}}, booktitle = {{Computational Logistics}}, editor = {{Bektac, Tolga and Coniglio, Stefano and Martinez-Sykora, Antonio and Voß, Stefan}}, isbn = {{978-3-319-68496-3}}, pages = {{306--320}}, publisher = {{Springer International Publishing}}, title = {{{Integrating Fleet Deployment into the Liner Shipping Cargo Allocation Problem}}}, year = {{2017}}, }