@inproceedings{48894, abstract = {{Recently different evolutionary computation approaches have been developed that generate sets of high quality diverse solutions for a given optimisation problem. Many studies have considered diversity 1) as a mean to explore niches in behavioural space (quality diversity) or 2) to increase the structural differences of solutions (evolutionary diversity optimisation). In this study, we introduce a co-evolutionary algorithm to simultaneously explore the two spaces for the multi-component traveling thief problem. The results show the capability of the co-evolutionary algorithm to achieve significantly higher diversity compared to the baseline evolutionary diversity algorithms from the literature.}}, author = {{Nikfarjam, Adel and Neumann, Aneta and Bossek, Jakob and Neumann, Frank}}, booktitle = {{Parallel Problem Solving from Nature (PPSN XVII)}}, editor = {{Rudolph, Günter and Kononova, Anna V. and Aguirre, Hernán and Kerschke, Pascal and Ochoa, Gabriela and Tu\v sar, Tea}}, isbn = {{978-3-031-14714-2}}, keywords = {{Co-evolutionary algorithms, Evolutionary diversity optimisation, Quality diversity, Traveling thief problem}}, pages = {{237–249}}, publisher = {{Springer International Publishing}}, title = {{{Co-Evolutionary Diversity Optimisation for the Traveling Thief Problem}}}, doi = {{10.1007/978-3-031-14714-2_17}}, year = {{2022}}, } @phdthesis{24760, abstract = {{Anwendungen von Laser-Sinter Bauteilen als Sichtteile sind aufgrund der vergleichsweise schlechten Oberflächenqualität sehr begrenzt. In dieser Arbeit werden dreidimensionale Kennwerte benutzt, um die Oberflächenqualität von Laser-Sinter Bauteiloberflächen und die Einflüsse aus unterschiedlichen Bereichen der gesamten Prozesskette zu evaluieren. Beispielsweise wurden objektive Kennwerte, mit deren Hilfe Orangenhaut zu identifizieren ist, und Prozessparameter, die diese deutlich vermindern, gefunden. Mittels Durchführung von haptischen Versuchen wurde das subjektive Empfinden ermittelt und konnten zu objektiven Kennwerten korreliert werden. Eine mikroskopische Betrachtung des flachen Oberflächenwinkels mit verschieden farbigen Pulvern zeigt neue Erkenntnisse zum Anschmelzvorgang von Partikeln an die Schmelze. Zur nachträglichen Glättung von Oberflächen wurden mechanische, chemische und optische Nachbehandlungsmethoden verwendet und deren Potential aufgezeigt. Eine abschließende neuartige Simulation der dreidimensionalen Topografie bildet die Grundlage für ein Programm zur automatischen und funktionsgerechten Orientierung von Bauteilen, welche am Beispiel eines realen Bauteils erfolgreich validiert wurde. Zusammengenommen zeigen die Ergebnisse, dass die richtige Wahl von Bauorientierung und Prozessparametern entscheidend für die Bauteilqualität ist und selbst eine aufwendige Nachbearbeitung eine ungeschickte Wahl derer nur schwerlich ausgleichen kann. }}, author = {{Delfs, Patrick}}, isbn = {{978-3-8440-7825-1}}, keywords = {{Additive Fertigung, Oberflächenqualität, 3D, Topografie, Simulation, PA12, Laser-Sintern, Rauheit}}, pages = {{126}}, publisher = {{Shaker Verlag GmbH}}, title = {{{Dreidimensionale Oberflächenanalyse und Topografie-Simulation additiv hergestellter Laser-Sinter Bauteile}}}, volume = {{22}}, year = {{2021}}, } @article{33649, author = {{Kessler, Jan and Calcavecchia, Francesco and Kühne, Thomas}}, issn = {{2513-0390}}, journal = {{Advanced Theory and Simulations}}, keywords = {{Multidisciplinary, Modeling and Simulation, Numerical Analysis, Statistics and Probability}}, number = {{4}}, publisher = {{Wiley}}, title = {{{Artificial Neural Networks as Trial Wave Functions for Quantum Monte Carlo}}}, doi = {{10.1002/adts.202000269}}, volume = {{4}}, year = {{2021}}, } @article{35575, author = {{Schulze Darup, Moritz and Alexandru, Andreea B. and Quevedo, Daniel E. and Pappas, George J.}}, issn = {{1066-033X}}, journal = {{IEEE Control Systems}}, keywords = {{Electrical and Electronic Engineering, Modeling and Simulation, Control and Systems Engineering, Electrical and Electronic Engineering, Modeling and Simulation, Control and Systems Engineering}}, number = {{3}}, pages = {{58--78}}, publisher = {{Institute of Electrical and Electronics Engineers (IEEE)}}, title = {{{Encrypted Control for Networked Systems: An Illustrative Introduction and Current Challenges}}}, doi = {{10.1109/mcs.2021.3062956}}, volume = {{41}}, year = {{2021}}, } @article{23431, abstract = {{As an effective and accurate method for modelling composite materials, mean-field homogenization is still not well studied in modelling non-linear and damage behaviours of UD composites. Investigated micro FE-simulations show that the matrix of UD composites exhibits different average plastic behaviour, named as average asymmetric matrix plasticity (AAMP), when the composite behaves different under shear, longitudinal and transverse loadings. In this study, a non-linear mean-field debonding model (NMFDM) combining a mean-field model and a fibre–matrix interface debonding model, is developed to simulate UD composites under consideration of AAMP, fibre–matrix interface damage and progressive failure. AAMP is considered by using so-called stress mode factor, which is expressed in terms of basic invariants of the matrix deviatoric stress tensor and is used as an indicator for detection of differences in the loading mode. The material behaviour of UD composites with imperfect interface is assumed identical as for perfect interface and stiffness reduced fibres. Progressive failure criteria are established with consideration of fibre breakage and matrix crack for different fibre orientations. As a representative example for the NMFDM, a C30/E201 UD composite is studied. To verify the model, experiments are conducted on polymers, carbon fibres and UD CFRPs. Finally, the model is applied to simulate a perforated CFRP laminate, which shows excellent prediction ability on deformation, debonding and progressive failure.}}, author = {{Cheng, C. and Wang, Z. and Jin, Z. and Ju, X. and Schweizer, Swetlana and Tröster, Thomas and Mahnken, Rolf}}, issn = {{1359-8368}}, journal = {{Composites Part B: Engineering}}, keywords = {{Non-linear mean-field homogenization Average asymmetric plasticity of matrix Fibre–matrix interface debonding Micro-mechanical FE-simulation Progressive failure}}, title = {{{Non-linear mean-field modelling of UD composite laminates accounting for average asymmetric plasticity of the matrix, debonding and progressive failure}}}, doi = {{10.1016/j.compositesb.2021.109209}}, volume = {{224}}, year = {{2021}}, } @inproceedings{24159, abstract = {{The online fitting of a microscopic traffic simulation model to reconstruct the current state of a real traffic area can be challenging depending on the provided data. This paper presents a novel method based on limited data from sensors positioned at specific locations and guarantees a general accordance of reality and simulation in terms of multimodal road traffic counts and vehicle speeds. In these considerations, the actual purpose of research is of particular importance. Here, the research aims at improving the traffic flow by controlling the Traffic Light Systems (TLS) of the examined area which is why the current traffic state and the route choices of individual road users are the matter of interest. An integer optimization problem is derived to fit the current simulation to the latest field measurements. The concept can be transferred to any road traffic network and results in an observation of the current multimodal traffic state matching at the given sensor position. First case studies show promosing results in terms of deviations between reality and simulation.}}, author = {{Malena, Kevin and Link, Christopher and Mertin, Sven and Gausemeier, Sandra and Trächtler, Ansgar}}, booktitle = {{VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems}}, isbn = {{978-989-758-513-5}}, keywords = {{Microscopic Traffic Simulation, Online State Estimation, Mixed Road Users, Sensor Fusion, Integer Programming, Route Choice, Vehicle2Infrastructure}}, location = {{Online Streaming}}, pages = {{386--395}}, publisher = {{SCITEPRESS}}, title = {{{Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources*}}}, volume = {{7}}, year = {{2021}}, } @article{41510, author = {{Pramanik, Sudipta and Andreiev, Anatolii and Hoyer, Kay-Peter and Schaper, Mirko}}, issn = {{0142-1123}}, journal = {{International Journal of Fatigue}}, keywords = {{Industrial and Manufacturing Engineering, Mechanical Engineering, Mechanics of Materials, General Materials Science, Modeling and Simulation}}, publisher = {{Elsevier BV}}, title = {{{Quasi in-situ analysis of fracture path during cyclic loading of double-edged U notched additively manufactured FeCo alloy}}}, doi = {{10.1016/j.ijfatigue.2021.106498}}, volume = {{153}}, year = {{2021}}, } @article{21436, abstract = {{Ultrasonic wire bonding is a solid-state joining process, used in the electronics industry to form electrical connections, e.g. to connect electrical terminals within semiconductor modules. Many process parameters affect the bond strength, such like the bond normal force, ultrasonic power, wire material and bonding frequency. Today, process design, development, and optimization is most likely based on the knowledge of process engineers and is mainly performed by experimental testing. In this contribution, a newly developed simulation tool is presented, to reduce time and costs and efficiently determine optimized process parameter. Based on a co-simulation of MATLAB and ANSYS, the different physical phenomena of the wire bonding process are considered using finite element simulation for the complex plastic deformation of the wire and reduced order models for the transient dynamics of the transducer, wire, substrate and bond formation. The model parameters such as the coefficients of friction between bond tool and wire and between wire and substrate were determined for aluminium and copper wire in experiments with a test rig specially developed for the requirements of heavy wire bonding. To reduce simulation time, for the finite element simulation a restart analysis and high performance computing is utilized. Detailed analysis of the bond formation showed, that the normal pressure distribution in the contact between wire and substrate has high impact on bond formation and distribution of welded areas in the contact area.}}, author = {{Schemmel, Reinhard and Krieger, Viktor and Hemsel, Tobias and Sextro, Walter}}, issn = {{0026-2714}}, journal = {{Microelectronics Reliability}}, keywords = {{Ultrasonic heavy wire bonding, Co-simulation, ANSYS, MATLAB, Process optimization, Friction coefficient, Copper-copper, Aluminium-copper}}, pages = {{114077}}, title = {{{Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization}}}, doi = {{https://doi.org/10.1016/j.microrel.2021.114077}}, volume = {{119}}, year = {{2021}}, } @article{37822, author = {{Han, Daxin and Yang, Keke and Meschut, Gerson}}, issn = {{0924-0136}}, journal = {{Journal of Materials Processing Technology}}, keywords = {{Industrial and Manufacturing Engineering, Metals and Alloys, Computer Science Applications, Modeling and Simulation, Ceramics and Composites}}, publisher = {{Elsevier BV}}, title = {{{Mechanical joining of glass fibre reinforced polymer (GFRP) through an innovative solid self-piercing rivet}}}, doi = {{10.1016/j.jmatprotec.2021.117182}}, volume = {{296}}, year = {{2021}}, } @inproceedings{21811, abstract = {{In order to reduce the fuel consumption and consequently the greenhouse emissions, the automotive industry is implementing lightweight constructions in the body in white production. As a result, the use of aluminum alloys is continuously increasing. Due to poor weldability of aluminum in combination with other materials, mechanical joining technologies like clinching are increasingly used. In order to predict relevant characteristics of clinched joints and to ensure the reliability of the process, it is simulated numerically during product development processes. In this regard the predictive accuracy of the simulated process highly depends on the implemented friction model. In particular, the frictional behavior between the sheet metals affects the geometrical formation of the clinched joint significantly. This paper presents a testing method, which enables to determine the frictional coefficients between sheet metal materials for the simulation of clinching processes. For this purpose, the correlation of interface pressure and the relative velocity between aluminum sheets in clinching processes is investigated using numerical simulation. Furthermore, the developed testing method focuses on the specimen geometry as well as the reproduction of the occurring friction conditions between two sheet metal materials in clinching processes. Based on a methodical approach the test setup is explained and the functionality of the method is proven by experimental tests using sheet metal material EN AW6014. }}, author = {{Rossel, Moritz Sebastian and Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}}, booktitle = {{Sheet Metal 2021}}, keywords = {{Tribology, Sheet Metal, Simulation}}, pages = {{81--88}}, publisher = {{Trans Tech Publications Ltd}}, title = {{{Development of a Method for the Identification of Friction Coefficients in Sheet Metal Materials for the Numerical Simulation of Clinching Processes}}}, doi = {{10.4028/www.scientific.net/KEM.883.81}}, volume = {{883}}, year = {{2021}}, } @inbook{21542, abstract = {{Using near-field (NF) scan data to predict the far-field (FF) behaviour of radiating electronic systems represents a novel method to accompany the whole RF design process. This approach involves so-called Huygens' box as an efficient radiation model inside an electromagnetic (EM) simulation tool and then transforms the scanned NF measured data into the FF. For this, the basic idea of the Huygens'box principle and the NF-to-FF transformation are briefly presented. The NF is measured on the Huygens' box around a device under test using anNF scanner, recording the magnitude and phase of the site-related magnetic and electric components. A comparison between a fullwave simulation and the measurement results shows a good similarity in both the NF and the simulated and transformed FF.Thus, this method is applicable to predict the FF behaviour of any electronic system by measuring the NF. With this knowledge, the RF design can be improved due to allowing a significant reduction of EM compatibility failure at the end of the development flow. In addition, the very efficient FF radiation model can be used for detailed investigations in various environments and the impact of such an equivalent radiation source on other electronic systems can be assessed.}}, author = {{Schröder, Dominik and Lange, Sven and Hangmann, Christian and Hedayat, Christian}}, booktitle = {{Tensorial Analysis of Networks (TAN) Modelling for PCB Signal Integrity and EMC Analysis}}, isbn = {{9781839530494}}, keywords = {{Huygens' box, NF-to-FF transformation, efficient FF radiation model, FF behaviour, EMI assessment, PCB, near-field measurements, efficient radiation model, far-field behaviour, RF design process, far-field prediction, Huygens'box principle, fullwave simulation, electronic system radiation, equivalent radiation source, electromagnetic simulation tool, near-field scan data, EM compatibility failure reduction}}, pages = {{315--346 (32)}}, publisher = {{ The Institution of Engineering and Technology (IET)}}, title = {{{Far-field prediction combining simulations with near-field measurements for EMI assessment of PCBs}}}, doi = {{10.1049/pbcs072e_ch14}}, year = {{2020}}, } @article{20678, author = {{Bielak, Christian Roman and Böhnke, Max and Beck, Robert and Bobbert, Mathias and Meschut, Gerson}}, journal = {{Journal of Advanced Joining Processes. }}, keywords = {{Clinching, process simulation, FEM, pre-straining, sensitivity analysis}}, publisher = {{Elsevier}}, title = {{{Numerical analysis of the robustness of clinching process considering the pre-forming of the parts }}}, doi = {{https://doi.org/10.1016/j.jajp.2020.100038}}, year = {{2020}}, } @inproceedings{19390, abstract = {{Due to the strong reduction of PV prices, storage plays a dominating role in overall system costs. A steeper elevation angle would result in a more balanced seasonal PV yield, at the cost of PV yield reductions during summer, but allowing reduced storage capacities. Additionally, the effect of a single-axis tracking system has been investigated, generating more electricity during the morning and evening hours, thus reducing daily storage requirements. The necessary PV size and storage capacities required for the German energy supply (1,500 TWh after electrification of all sectors) via 100% renewable energies and a 50% solar share have been calculated via the HOMER Pro software, considering the bridging of periods of "dark lulls“ in winter, using costs of 2030 (Table 1). Results: The increase of module elevation angles above the typical 30° leads to a reduction of investment and supply costs. The optimum is reached at a cost reduction of -1.5% for an elevation angle at the latitude of the installation site. An explanation is that high elevation angles are favorable for clear winter days, but not at all for the critical days with diffuse irradiance only, so the battery capacity must be increased. For the same reason, tracking systems do not offer any cost advantage (at least for the ones without an option for horizontal positioning during diffuse days).}}, author = {{Krauter, Stefan and Rustemovic, D. and Khatibi, Arash}}, booktitle = {{Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020}}, isbn = {{3-936338-73-6}}, keywords = {{Energy Storage, PV system integration, Large Grid-connected PV systems, Simulation, Energy Supply Options}}, location = {{online}}, pages = {{1818 -- 1819}}, title = {{{Reduction of required storage capacities for a 100% renewable energy supply in Germany, if new PV systems are installed with east-west tracking systems at increased elevation angles}}}, doi = {{10.4229/EUPVSEC20202020-6BV.5.10}}, year = {{2020}}, } @article{29722, abstract = {{Modern user interfaces (UIs) are increasingly expected to be plastic, in the sense that they retain a constant level of usability, even when subjected to context changes at runtime. Self-adaptive user interfaces (SAUIs) have been promoted as a solution for context variability due to their ability to automatically adapt to the context-of-use at runtime. The development of SAUIs is a challenging and complex task as additional aspects like context management and UI adaptation have to be covered. In classical model-driven UI development approaches, these aspects are not fully integrated and hence introduce additional complexity as they represent crosscutting concerns. In this paper, we present an integrated model-driven development approach where a classical model-driven development of UIs is coupled with a model-driven development of context-of-use and UI adaptation rules. We base our approach on the core UI modeling language IFML and introduce new modeling languages for context-of-use (ContextML) and UI adaptation rules (AdaptML). The generated UI code, based on the IFML model, is coupled with the context and adaptation services, generated from the ContextML and AdaptMLmodel, respectively. The integration of the generated artifacts, namely UI code, context, and adaptation services in an overall rule-based execution environment, enables runtime UI adaptation. The benefit of our approach is demonstrated by two case studies, showing the development of SAUIs for different application scenarios and a usability study which has been conducted to analyze end-user satisfaction of SAUIs.}}, author = {{Yigitbas, Enes and Jovanovikj, Ivan and Biermeier, Kai and Sauer, Stefan and Engels, Gregor}}, issn = {{1619-1366}}, journal = {{Software and Systems Modeling}}, keywords = {{Modelling and Simulation, Software}}, number = {{5}}, pages = {{1057--1081}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Integrated model-driven development of self-adaptive user interfaces}}}, doi = {{10.1007/s10270-020-00777-7}}, volume = {{19}}, year = {{2020}}, } @article{33263, abstract = {{Dynamical systems often admit geometric properties that must be taken into account when studying their behavior. We show that many such properties can be encoded by means of quiver representations. These properties include classical symmetry, hidden symmetry, and feedforward structure, as well as subnetwork and quotient relations in network dynamical systems. A quiver equivariant dynamical system consists of a collection of dynamical systems with maps between them that send solutions to solutions. We prove that such quiver structures are preserved under Lyapunov--Schmidt reduction, center manifold reduction, and normal form reduction.}}, author = {{Nijholt, Eddie and Rink, Bob W. and Schwenker, Sören}}, issn = {{1536-0040}}, journal = {{SIAM Journal on Applied Dynamical Systems}}, keywords = {{Modeling and Simulation, Analysis}}, number = {{4}}, pages = {{2428--2468}}, publisher = {{Society for Industrial & Applied Mathematics (SIAM)}}, title = {{{Quiver Representations and Dimension Reduction in Dynamical Systems}}}, doi = {{10.1137/20m1345670}}, volume = {{19}}, year = {{2020}}, } @article{34670, author = {{Black, Tobias}}, issn = {{0218-2025}}, journal = {{Mathematical Models and Methods in Applied Sciences}}, keywords = {{Applied Mathematics, Modeling and Simulation}}, number = {{06}}, pages = {{1075--1117}}, publisher = {{World Scientific Pub Co Pte Lt}}, title = {{{Global generalized solutions to a forager–exploiter model with superlinear degradation and their eventual regularity properties}}}, doi = {{10.1142/s0218202520400072}}, volume = {{30}}, year = {{2020}}, } @inproceedings{15332, abstract = {{Artificial intelligence (AI) has the potential for far-reaching – in our opinion – irreversible changes. They range from effects on the individual and society to new societal and social issues. The question arises as to how students can learn the basic functioning of AI systems, what areas of life and society are affected by these and – most important – how their own lives are affected by these changes. Therefore, we are developing and evaluating school materials for the German ”Science Year AI”. It can be used for students of all school types from the seventh grade upwards and will be distributed to about 2000 schools in autumn with the support of the Federal Ministry of Education and Research. The material deals with the following aspects of AI: Discussing everyday experiences with AI, how does machine learning work, historical development of AI concepts, difference between man and machine, future distribution of roles between man and machine, in which AI world do we want to live and how much AI would we like to have in our lives. Through an accompanying evaluation, high quality of the technical content and didactic preparation is achieved in order to guarantee the long-term applicability in the teaching context in the different age groups and school types. In this paper, we describe the current state of the material development, the challenges arising, and the results of tests with different classes to date. We also present first ideas for evaluating the results.}}, author = {{Schlichtig, Michael and Opel, Simone Anna and Budde, Lea and Schulte, Carsten}}, booktitle = {{ISSEP 2019 - 12th International conference on informatics in schools: Situation, evaluation and perspectives, Local Proceedings}}, editor = {{Jasutė, Eglė and Pozdniakov, Sergei}}, isbn = {{978-9925-553-27-3}}, keywords = {{Artificial Intelligence, Machine Learning, Teaching Material, Societal Aspects, Ethics. Social Aspects, Science Year, Simulation Game}}, location = {{Lanarca}}, pages = {{65 -- 73}}, title = {{{Understanding Artificial Intelligence – A Project for the Development of Comprehensive Teaching Material}}}, volume = {{12}}, year = {{2019}}, } @phdthesis{41958, abstract = {{Das Nasspressverfahren ist ein Serienherstellungsprozess für Bauteile aus duroplastischen Faserverbundkunststoffen (FVK) mit einer geringen Geometriekomplexität. Im Rahmen dieser Arbeit wurde ein modifiziertes Nasspressverfahren untersucht, welches die Herstellung von hybriden Blech-FVK-Strukturen ermöglicht. Die stoffschlüssige Verbindung zwischen dem metallischen Trägerbauteil und einem lokalen FVK-Verstärkungselement wird durch Co-Bonding im Nasspresswerkzeug aufgebaut. Epoxidbasierte Matrixharze und Klebstoffe wurden mit Methoden der Klebtechnik sowie thermischen und rheometrischen Prüfungen charakterisiert, um ein materialspezifisches Fertigungsprozessfenster einzugrenzen. Experimentelle Untersuchungen zum Nasspressen von GFK-Laminaten und Stahl-GFK-Hybridstrukturen fokussierten die Mikrostruktur und das strukturelle Verhalten von stoffschlüssigen Hybridverbindungen. Unter anderem wurden Einflüsse von zeit-, temperatur- und druckabhängigen Fertigungsparametern sowie der Einsatz von Strukturklebstofffilmen und internen Trennmitteln analysiert. Anhand von Fallturmtests an hybriden Demonstratorkomponenten konnte das modifizierte Nasspressverfahren für die Herstellung crashrelevanter Karosseriebauteile qualifiziert werden.}}, author = {{Opdemom, Hermann}}, isbn = {{978-3-8440-6428-5}}, keywords = {{Leichtbau, Faserverbundkunststoffe, Nasspressverfahren, Hybridbauteile, Rheologie, Klebtechnik, Co-Bonding}}, pages = {{178}}, publisher = {{Shaker Verlag}}, title = {{{Experimentelle Untersuchung einse modifzierten Nasspressverfahrens für die Herstellung von hybriden Metall-Faserverbundkunststoff-Bauteilen}}}, volume = {{2019,35}}, year = {{2019}}, } @phdthesis{10000, abstract = {{Ultraschall wird zur Effizienzsteigerung in verfahrenstechnischen Prozessen eingesetzt. Die Betriebsparamter der Ultraschallsysteme werden empirisch ermittelt, da derzeit keine systematische Analyse der Wechselwirkung zwischen Ultraschallwandler und Schallfeld sowie kein Verfahren zur Messung der Kavitationsaktivität ohne zusätzlichen Sensor existieren. Auf Basis einer experimentellen Analyse des betrachteten sonochemischen Reaktors wird ein Finite-Elemente-Modell aufgebaut, das die Wechselwirkung zwischen Schallfeld und Ultraschallwandler berücksichtigt. Die modellbasierte Analyse zeigt, dass wegen der akustischen Eigenschaften des Autoklavs nur direkt an der Sonotrode Kavitation entsteht. Die Wechselwirkung zwischen Ultraschallwandler und Schallfeld ermöglicht Aussagen über das Schallfeld und die Kavitationsaktivität auf Basis der Rückwirkung auf den Ultraschallwandler. Die lineare Schalldruckverteilung ermöglicht eine Prognose über die Verteilung von Kavitationszonen. Das beschriebene Modell liefert wertvolle Erkenntnisse für die Auslegung, Analyse und Skalierung sonochemischer Reaktoren. Auf Grund der rauen Prozessrandbedingungen ist die Applikation von Sensoren zur Überwachung der Kavitationsaktivität in vielen sonochemischen Prozessen nicht möglich. Zur prozessbegleitenden Messung der Kavitationsaktivität wird ein Verfahren entwickelt, das die Bewertung der Kavitationsaktivität durch Auswertung der Rückwirkung auf den Ultraschallwandler erlaubt. Das Messverfahren ermöglicht eine vorhersagbare und reproduzierbare Durchführung kavitationsbasierter Prozesse und stellt eine wichtige Erweiterung für bestehende und neue Ultraschallsysteme dar.}}, author = {{Bornmann, Peter}}, keywords = {{Sonochemie, Akustische Kavitation, Kavitationsmessung, Kavitationsdetektion, FEM-Simulation Ultraschallwandler, Prozessüberwachung, FEM-Simulation Schallfeld, Self-Sensing, Piezoelektrische Ultraschallwandler, Ultraschallreinigung}}, publisher = {{Shaker}}, title = {{{Modellierung und experimentelle Charakterisierung der Wechselwirkung zwischen Ultraschallwandler und Flüssigkeit in kavitationsbasierten Prozessen}}}, year = {{2019}}, } @inproceedings{10598, abstract = {{Approximate computing has become a very popular design strategy that exploits error resilient computations to achieve higher performance and energy efficiency. Automated synthesis of approximate circuits is performed via functional approximation, in which various parts of the target circuit are extensively examined with a library of approximate components/transformations to trade off the functional accuracy and computational budget (i.e., power). However, as the number of possible approximate transformations increases, traditional search techniques suffer from a combinatorial explosion due to the large branching factor. In this work, we present a comprehensive framework for automated synthesis of approximate circuits from either structural or behavioral descriptions. We adapt the Monte Carlo Tree Search (MCTS), as a stochastic search technique, to deal with the large design space exploration, which enables a broader range of potential possible approximations through lightweight random simulations. The proposed framework is able to recognize the design Pareto set even with low computational budgets. Experimental results highlight the capabilities of the proposed synthesis framework by resulting in up to 61.69% energy saving while maintaining the predefined quality constraints.}}, author = {{Awais, Muhammad and Ghasemzadeh Mohammadi, Hassan and Platzner, Marco}}, booktitle = {{26th IFIP/IEEE International Conference on Very Large Scale Integration (VLSI-SoC)}}, keywords = {{Approximate computing, High-level synthesis, Accuracy, Monte-Carlo tree search, Circuit simulation}}, pages = {{219--224}}, title = {{{An MCTS-based Framework for Synthesis of Approximate Circuits}}}, doi = {{10.1109/VLSI-SoC.2018.8645026}}, year = {{2018}}, }